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# Rencontre de Physique des Particules 2015
15-16 janvier 2015
Institut Henri Poincaré
Fuseau horaire Europe/Paris
## Small radius jets to all orders
15 janv. 2015 à 09:25
14m
Chair: Sébastien Descotes-Genon, Amphi Hermite (Institut Henri Poincaré)
### Chair: Sébastien Descotes-Genon, Amphi Hermite
#### Institut Henri Poincaré
11, rue Pierre et Marie Curie 75005 Paris
### Orateur
M. Frédéric Dreyer (LPTHE)
### Description
As hadron collider physics continues to push the boundaries of precision, it becomes increasingly important to have methods for predicting properties of jets across a broad range of jet radius values R, and in particular for small R. In this presentation we will start with a brief review of jet physics at hadron colliders, and introduce a method to resum all leading logarithmic terms, $\alpha_s \ln R$, in the limit of small R, for a wide variety of observables. These include the inclusive jet spectrum, jet vetoes for Higgs physics and jet substructure tools. We will examine and comment on the underlying order-by-order convergence of the perturbative series for different R values.
### Documents de présentation
Transparents
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http://www.mobileread.com/forums/showthread.php?t=73239 | Register Guidelines E-Books Search Today's Posts Mark Forums Read
02-09-2010, 02:39 PM #1 superplinio Junior Member Posts: 8 Karma: 10 Join Date: Nov 2009 Device: Sony PRS 600 Author names I find the information about the authors of a book a bit confusing. I like to order the authors using the surname so I want in the authors filter to see something like this: * Asimov, Isaac * Card, Orson Scott etc. My first attempt was to introduce the author as "Asimov, Isaac" but Calibre understands that there are two different authors called "Asimov" and "Isaac" respectively. The second attempt was to introduce "Isaac Asimov". The name in correctly identified and the Author sort shows "Asimov, Isaac" as I wanted. But sadly the information of the authors that is normally showed is that of the Authors name and not the Authors sort, so I have the collection ordered by name and not by surname as I wanted. The final solution is a not very elegant fix, I put as the name "Asimov Isaac" and fixed the author sort manually. So my main question is... Is it possible to show the author sort column in the main table of calibre instead of the author name? is it any strategy to sort authors by surname different from the one I had chosen. Regards...
02-09-2010, 02:56 PM #2
theducks
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Quote:
Originally Posted by superplinio I find the information about the authors of a book a bit confusing. I like to order the authors using the surname so I want in the authors filter to see something like this: * Asimov, Isaac * Card, Orson Scott etc. My first attempt was to introduce the author as "Asimov, Isaac" but Calibre understands that there are two different authors called "Asimov" and "Isaac" respectively. The second attempt was to introduce "Isaac Asimov". The name in correctly identified and the Author sort shows "Asimov, Isaac" as I wanted. But sadly the information of the authors that is normally showed is that of the Authors name and not the Authors sort, so I have the collection ordered by name and not by surname as I wanted. The final solution is a not very elegant fix, I put as the name "Asimov Isaac" and fixed the author sort manually. So my main question is... Is it possible to show the author sort column in the main table of calibre instead of the author name? is it any strategy to sort authors by surname different from the one I had chosen. Regards...
That is what "Author sort" does
Enter "Isaac Asimov" as Author
Click the button next to the Author sort field in the Meta data Browser.
Save
When you sort the Library by the Author column,
Isaac Asimov will be in the proper place in the "A"'s, not in the "I"'s
02-09-2010, 07:26 PM #3 superplinio Junior Member Posts: 8 Karma: 10 Join Date: Nov 2009 Device: Sony PRS 600 Yes you are right but there are some problems: * The name is shown as "Isaac Asimov" although ordered as "Asimov, Isaac", it is a bit confusing * In the filter by authors (the pane at the left side) the authors are ordered by authors name (not by authors sort) so Dan Brown is before Isaac Asimov * The device does not take into account the author sort but the author name, so again we have an order by name and not by surname. What I am trying to say is that the author sort it is pretty useless this way if it is not used consistently in all the program.
02-09-2010, 08:14 PM #4 JMikeD Evangelist Posts: 452 Karma: 15000 Join Date: Jul 2008 Device: Various and sundry Deleted. Last edited by JMikeD; 02-09-2010 at 08:26 PM.
02-10-2010, 07:45 PM #5 superplinio Junior Member Posts: 8 Karma: 10 Join Date: Nov 2009 Device: Sony PRS 600 There is no more opinions about this issue, I think it is important because I know some people that are using the same workaround as me (introducing the author as "Asimov Isaac") to avoid the ordering by name both in Calibre and in the device
02-11-2010, 06:35 AM #6 chaley "chaley", not "charley" Posts: 5,653 Karma: 1137414 Join Date: Jan 2010 Location: France Device: Many android devices calibre 0.6.39 provides three options for how author_sort is computed from author. Using one of these options may help you get what you want. 1) As it always has been. Author is assumed to be in FN LN format, and author_sort is set to LN, FN 2) Copy author to author_sort without modification. This is useful for those who always enter authors and LN, FN 3) A combination of 1 and 2. Use #2 if there is a comma in the name, otherwise use #1. You control the method using calibre's new 'tweaks' feature. There will be a file in your calibre working folder called tweaks.py. Where this is depends on your system and version. For me, using Windows 7, it is here Code: `"C:\Users\charles\AppData\Roaming\calibre\tweaks.py"` Change the value of the variable author_sort_copy_method to the value indicated by the comments. Make sure it stays quoted. The default behavior is #1. If you change the variable to something other than indicated in the comments, the behavior will remain the default. If the author_sort_copy_method and associated comments are not already in the tweaks.py file, see 'resources/default_tweaks.py' in your calibre installation directory for this information.
02-27-2010, 04:58 AM #7 SnakeMM Member Posts: 21 Karma: 10 Join Date: Feb 2010 Device: HTC Magic After changing "invert" to "copy" how to change in bulk mode order of sorting? Ok I have done this. .mr-forums-btf-lastpost-in-sig-l-text-sm-height { width: 650px; height: 150px; margin-top: 10px; } Last edited by SnakeMM; 02-27-2010 at 05:01 AM.
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https://www.backyardrave.be/Jan-01/13984/obtuse-angle-example.html | # obtuse angle example
Obtuse Meaning | Best 15 Definitions of Obtuse- obtuse angle example ,What does obtuse mean? Greater than 90 degrees and less than 180 degrees. (adjective) An obtuse angle. A person who is slow to comprehend or understand, or who is dull or insensitive. We all know such people. See also abstruse.4.1: Classify Triangles - K12 LibreTexts28/11/2020· Example $$\PageIndex{4}$$ Which term best describes $$\Delta RST$$ below? Figure $$\PageIndex{13}$$ Solution This triangle has one labeled obtuse angle of $$92^{\circ}$$. Triangles can have only one obtuse angle, so it is an obtuse triangle.
We're an enterprise that export obtuse angle example to China, we're approved by the relevant state registratio. Key obtuse angle example and sell to many countries in overseas, product obtainable upon request. We've the spirit of 'customer first, honesty first' principle, using a quantity of enterprises established long-term cooperative connection.
### Example of obtuse angle
22/6/2019· 👍 Correct answer to the question Example of obtuse angle - e-eduanswers Answer from each drop-down menu. e characteristics of a borane molecule (bh). the lewis structure and table of electronegativities are given olecular shape is and the molecule is reset
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### Obtuse angle - Math Doubts
Hence, the angle made by the ray $\overrightarrow{OP}$ to reach from its initial position to final position is an example to an obtuse angle. 2 The angle between any two lines which have a common vertex is measured by considering one line as baseline to another and vice-versa to measure the angle.
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### Definition of Obtuse Angle
An obtuse angle is more than 90° but less than 180°. In other words, it is between a right angle and a straight angle.
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### Obtuse Angle - Vedantu
Obtuse angle Real - Life Example: Imagine tilting a car seat back so that you can be seated comfortably. You'd push it in the back of the position, closer to lying flat. Where the seat's bottom and the back meet would be an obtuse angle because you've pushed ...
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### 4.1: Classify Triangles - K12 LibreTexts
28/11/2020· Example $$\PageIndex{4}$$ Which term best describes $$\Delta RST$$ below? Figure $$\PageIndex{13}$$ Solution This triangle has one labeled obtuse angle of $$92^{\circ}$$. Triangles can have only one obtuse angle, so it is an obtuse triangle.
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### Obtuse Angle - an overview | ScienceDirect Topics
The basic idea of the most-obtuse-angle rule with dual pivoting index is the same as most-obtuse-angle rule with the (primal) pivoting index defined by (3). At one iteration, we are inclined to choose among all basic variables the one with the lowest possible pivoting index to leave the basis, and among all non-basic variables choose the one with the highest possible pivoting index to enter ...
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### Trig Obtuse Angles - Yoshiwara Books
Obtuse Angles. An obtuse angle has measure between $$90\degree$$ and $$180\degree\text{.}$$ In this section we will define the trigonometric ratios of an obtuse angle as follows. Place the angle $$\theta$$ in standard position and choose a point $$P$$ with
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### Obtuse Angle - Definition, Calculation | Solved Examples
For example, bay windows have corner angles that are obtuse angles. Furthermore, recliners in their reclined form give an indication of the obtuse angle between the seat and the backrest. Similarly, chaise lounges can show obtuse angles.
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### Obtuse angle - Math Doubts
Hence, the angle made by the ray $\overrightarrow{OP}$ to reach from its initial position to final position is an example to an obtuse angle. 2 The angle between any two lines which have a common vertex is measured by considering one line as baseline to another and vice-versa to measure the angle.
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### Example of obtuse angle - estudyassistant
22/6/2019· Example of obtuse angle ... Questions Mathematics, 31.07.2019 04:30 An airplane has a maximum capacity of 118 passengers. the flight attendant has loaded 40 passengers. which inequality represents the solution set that...
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### Definition of Obtuse Angle
An obtuse angle is more than 90° but less than 180°. In other words, it is between a right angle and a straight angle.
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### Obtuse Angle - Vedantu
Obtuse angle Real - Life Example: Imagine tilting a car seat back so that you can be seated comfortably. You'd push it in the back of the position, closer to lying flat. Where the seat's bottom and the back meet would be an obtuse angle because you've pushed ...
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### Obtuse Angle - an overview | ScienceDirect Topics
The basic idea of the most-obtuse-angle rule with dual pivoting index is the same as most-obtuse-angle rule with the (primal) pivoting index defined by (3). At one iteration, we are inclined to choose among all basic variables the one with the lowest possible pivoting index to leave the basis, and among all non-basic variables choose the one with the highest possible pivoting index to enter ...
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### obtuse angle - English-Chinese Dictionary - Glosbe
obtuse angle translation in English-Chinese dictionary Showing page 1. Found 1 sentences matching phrase "obtuse angle".Found in 3 ms. Translation memories are created by human, but computer aligned, which might cause mistakes.
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### What Are Some Real World Examples of an Obtuse Angle?
17/4/2020· Other real world examples of an obtuse angle include the angle between the screen and the base of an opened laptop, a hockey stick, an accordion hand fan and between the wings of a boomerang. In general, obtuse angles are observed whenever two sides
WhatsApp | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 1, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.6677987575531006, "perplexity": 1658.992840102399}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.3, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2022-05/segments/1642320303729.69/warc/CC-MAIN-20220122012907-20220122042907-00144.warc.gz"} |
https://zenodo.org/record/3946230/export/xd | Journal article Open Access
# Affect Improvements and Measurement Concordance Between a Subjective and an Accelerometric Estimate of Physical Activity
Pannicke, Björn; Reichenberger, Julia; Schultchen, Dana; Pollatos, Olga; Blechert, Jens
### Dublin Core Export
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<oai_dc:dc xmlns:dc="http://purl.org/dc/elements/1.1/" xmlns:oai_dc="http://www.openarchives.org/OAI/2.0/oai_dc/" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://www.openarchives.org/OAI/2.0/oai_dc/ http://www.openarchives.org/OAI/2.0/oai_dc.xsd">
<dc:creator>Pannicke, Björn</dc:creator>
<dc:creator>Reichenberger, Julia</dc:creator>
<dc:creator>Schultchen, Dana</dc:creator>
<dc:creator>Pollatos, Olga</dc:creator>
<dc:creator>Blechert, Jens</dc:creator>
<dc:date>2020-07-01</dc:date>
<dc:description>Objectives: Physical activity (PA) positively influences several aspects of mental well-being including affect improvements. Yet, the fact that subjective and objective measures of PA often diverge challenges research on the relationship of PA and affect. Methods: Subjective (ecological momentary assessment, EMA) and objective (combined heart rate and accelerometric activity tracker) measures of PA alongside repeated ratings of positive and negative affects were obtained from 37 participants over 7 consecutive days. Results: Subjective and objective PA were significantly positively correlated. Affect improvements, that is, negative affect decrease as well as positive affect increase, were predicted by both subjective (EMA) and objective (activity tracker) data. Conclusions: Measurement concordance supports the validity of both assessment strategies. Affect improvements result from both subjective representations of one’s own activity as well as from physiological mechanisms of PA that one is not aware of, suggesting two independent routes to affect improvements.</dc:description>
<dc:identifier>https://zenodo.org/record/3946230</dc:identifier>
<dc:identifier>10.1027/2512-8442/a000050</dc:identifier>
<dc:identifier>oai:zenodo.org:3946230</dc:identifier>
<dc:relation>info:eu-repo/grantAgreement/EC/H2020/639445/</dc:relation>
<dc:rights>info:eu-repo/semantics/openAccess</dc:rights>
<dc:subject>physical activity, affect improvements, ecological momentary assessment, accelerometry, everyday life</dc:subject>
<dc:title>Affect Improvements and Measurement Concordance Between a Subjective and an Accelerometric Estimate of Physical Activity</dc:title>
<dc:type>info:eu-repo/semantics/article</dc:type>
<dc:type>publication-article</dc:type>
</oai_dc:dc>
29
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# 40% of the employees in a factory are workers...
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40% of the employees in a factory are workers... [#permalink] 08 Oct 2010, 04:37
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40% of the employees in a factory are workers. All the remaining employees are executives. The annual income of each worker is $390.The annual income of each executive is$420. What is the average annual income of all the employees in the factory together?
A. 390
B. 405
C. 408
D. 415
E. 420
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Re: 40% of the employees in a factory are workers... [#permalink] 08 Oct 2010, 04:43
pzazz12 wrote:
40% of the employees in a factory are workers. All the remaining employees are executives. The annual income of each worker is $390.The annual income of each executive is$420. What is the average annual income of all the employees in the factory together?
A. 390
B. 405
C. 408
D. 415
E. 420
0.4x390 + 0.6x420 = 408 --> C
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Re: 40% of the employees in a factory are workers... [#permalink] 08 Oct 2010, 06:40
Yes it should be 408 i.e C
Re: 40% of the employees in a factory are workers... [#permalink] 08 Oct 2010, 06:40
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https://elteoremadecuales.com/excision-theorem/?lang=pt | # Excision theorem
Excision theorem In algebraic topology, um ramo da matemática, the excision theorem is a theorem about relative homology and one of the Eilenberg–Steenrod axioms. Given a topological space {estilo de exibição X} and subspaces {estilo de exibição A} e {estilo de exibição U} de tal modo que {estilo de exibição U} is also a subspace of {estilo de exibição A} , the theorem says that under certain circumstances, we can cut out (excise) {estilo de exibição U} from both spaces such that the relative homologies of the pairs {estilo de exibição (Xsetminus U,Asetminus U)} em {estilo de exibição (X,UMA)} são isomórficos.
This assists in computation of singular homology groups, as sometimes after excising an appropriately chosen subspace we obtain something easier to compute.
Conteúdo 1 Teorema 1.1 Declaração 1.2 Proof Sketch 2 Formulários 2.1 Eilenberg–Steenrod Axioms 2.2 Mayer-Vietoris Sequences 3 Veja também 4 Referências 5 Bibliography Theorem Statement If {displaystyle Usubseteq Asubseteq X} are as above, nós dizemos isso {estilo de exibição U} can be excised if the inclusion map of the pair {estilo de exibição (Xsetminus U,Asetminus U)} em {estilo de exibição (X,UMA)} induces an isomorphism on the relative homologies: {estilo de exibição H_{n}(Xsetminus U,Asetminus U)cong H_{n}(X,UMA)} The theorem states that if the closure of {estilo de exibição U} is contained in the interior of {estilo de exibição A} , então {estilo de exibição U} can be excised.
Muitas vezes, subspaces that do not satisfy this containment criterion still can be excised—it suffices to be able to find a deformation retract of the subspaces onto subspaces that do satisfy it.
Proof Sketch The proof of the excision theorem is quite intuitive, though the details are rather involved. The idea is to subdivide the simplices in a relative cycle in {estilo de exibição (X,UMA)} to get another chain consisting of "menor" simples, and continuing the process until each simplex in the chain lies entirely in the interior of {estilo de exibição A} or the interior of {displaystyle Xsetminus U} . Since these form an open cover for {estilo de exibição X} and simplices are compact, we can eventually do this in a finite number of steps. This process leaves the original homology class of the chain unchanged (this says the subdivision operator is chain homotopic to the identity map on homology). In the relative homology {estilo de exibição H_{n}(X,UMA)} , então, this says all the terms contained entirely in the interior of {estilo de exibição U} can be dropped without affecting the homology class of the cycle. This allows us to show that the inclusion map is an isomorphism, as each relative cycle is equivalent to one that avoids {estilo de exibição U} entirely.
Applications Eilenberg–Steenrod Axioms The excision theorem is taken to be one of the Eilenberg–Steenrod Axioms.
Mayer-Vietoris Sequences The Mayer–Vietoris sequence may be derived with a combination of excision theorem and the long-exact sequence.[1] See also Homotopy excision theorem References ^ See Hatcher 2002, p.149, for example Bibliography Joseph J. Rotman, Uma Introdução à Topologia Algébrica, Springer-Verlag, ISBN 0-387-96678-1 Allen Hatcher, Algebraic Topology. Cambridge University Press, Cambridge, 2002. Categorias: Homology theoryTheorems in topology
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https://aiucl.github.io/large-class/ | Training with a large number of classes
davidbarber Mar 15, 2017 · 3 mins read
In machine learning we often face the issue of a very large number of classes in a classification problem. This causes a bottleneck in the computation. There’s though a simple and effective way to deal with this.
Probabilistic Classification
In areas like Natural Language Processing (NLP) a common task is to predict the next word in sequence (like in preditictive text on a smartphone or in learning word embeddings). For input $x$ and class label $c$, the probability of predicting class $c$ is
where $u_\theta(c,x)$ is some defined function with parameters $\theta$. For example, $u_\theta(c,x)=\exp(w_c'x)$, where $w_c$ is a parameter vector for class $c$ and $x$ is the vector input. The normalising term is
The task is then to adjust the parameters $\theta$ to maximise the probability of the correct class for each of the training points.
However, if there are $C=100,000$ words in the dictionary, this means calculating the normalisation $Z$ for each datapoint is going to be expensive. There have been a variety of approaches suggested over the years to make computationally efficient approximations, many based on importance sampling.
Why plain Importance Sampling doesn’t work
A standard approach to approximating $Z_\theta(x)$ is to use
where $q$ is an importance distribution over all $C$ classes. We can then form an approximation by sampling from $q$ a small number $S$ of classes to form a sample bag ${\cal{S}}$ and using
The problem with this approach is that it results in a potentially catastrophic under-estimate of $Z_\theta(x)$. If the classifier is working well, we want that $u_\theta(c,x)$ is much higher than $u_\theta(d,x)$ for any incorrect class $d$. Hence, unless the importance sample bag ${\cal{S}}$ includes class $c$, then the normalisation approximation will miss this significant mass and the probability approximation
will be wildly inaccurate, see figure (a) below. This is the source of the historically well-documented instabilities in training large-scale classifiers.
Making Importance Sampling work
However, there is an easy fix for this – simply ensure that ${\cal{S}}$ includes the correct class $c$.
On the left above we show for $C=10,000$ classes the ratio $u_\theta(c,x)/Z_\theta(x)$ on the $x$-axis against its approximation $u_\theta(c,x)/\tilde{Z}_\theta(x)$ on the $y$-axis. Each dot represents a different randomly drawn set of $u$ values. Red, green and blue represent 10, 20 and 50 importance samples respectively. The ideal estimation would be such that all points are along the line $y=x$. Note the vertical scale – these values are supposed to be probabilities and lie between 0 and 1. Even as we increase the number of importance samples, this remains a wildly incorrect estimation of the probability.
On the right above we show the same probability estimate but now simply also include the correct class in the set ${\cal{S}}$. The vertical scale is now sensible and the estimated probabiliy is close to the true value.
Deep Learning Recurrent NLP models
We applied this method to learning word embeddings for a deep recurrent network. The training objective was standard maximum likelihood, but with the normalisation approximation above. Below we plot the exact log likelihood ($y$-axis) against the optimisation gradient ascent iteration ($x$-axis). We also plot the exact log likelihood for some alternative training approaches. As we see, standard Importance Sampling becomes unstable as learning progresses. However our simple modification stabilizes learning and is competitive against a range of alternatives including Noise Contrastive Estimation, Ranking approaches, Negative Sampling and BlackOut.
This is so simple and works so well that we use this in all our NLP deep learning training experiments.
This forms the basis for our paper Complementary Sum Sampling for Likelihood Approximation in Large Scale Classification which will appear in AISTATS 2017.
Written by davidbarber
David is the Director of the UCL Centre for Artificial Intelligence | {"extraction_info": {"found_math": true, "script_math_tex": 36, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.8474293947219849, "perplexity": 541.2999536298037}, "config": {"markdown_headings": false, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2022-27/segments/1656104514861.81/warc/CC-MAIN-20220705053147-20220705083147-00431.warc.gz"} |
http://www.concordy.com/sci-tech/2015/10/nobel-prize-winners-prove-neutrinos-have-mass/ | # Nobel Prize winners prove neutrinos have mass
0
125
Takaaki Kajita of the Super-Kamiokande Collaboration, University of Tokyo, and Arthur B. McDonald of the Sudbury Neutrino Observatory Collaboration, Queen’s University, were jointly awarded the Nobel Prize in Physics “for the discovery of neutrino oscillations, which shows that neutrinos have mass,” according to the Nobel Prize’s website.
Beyond the common particles of protons, neutrons and electrons, which many a high schooler has had to memorize, is a whole set of particles known as elementary particles.
Among these are quarks, muons, taus and neutrinos.
Neutrinos have puzzled physicists for many years despite their bountiful abundance.
According to the Nobel Prize press release, “thousands of billions of neutrinos are flowing through your body every second,” released mainly by the sun. However, the press release notes that these particles “hardly ever interact with matter.”
Quantifying the neutrino has proven very difficult because of its lack of reactivity.
However, two separate research facilities have successfully used Cherenkov radiation to explore the neutrino.
One of these facilities is the Super-Kamiokande Neutrino Detector in Kamioka, Japan. Located about one kilometer underground, the Super-Kamiokande is basically a large cylinder full of ultrapure water.
The purpose of the cylinder is to observe neutrinos passing through the earth.
Since neutrinos travel at the speed of light, it is virtually impossible to tell them apart from photons of light – at least, in air it is impossible.
However, when light passes through a denser medium such as water, it is slowed slightly by about 25 percent.
Neutrinos, on the other hand, are unaffected by water, and continue to travel at the speed of light.
Although the neutrinos’ speed is not altered by the water, the water is affected by the neutrinos.
When a charged neutrino passes through water, it disrupts the electromagnetic field of the water, sending out a shockwave of cone-shaped light, called Cherenkov radiation.
Determining the angle of the cone of radiation can give both the direction and the velocity of the disrupting particle, and in this case neutrinos.
To detect these shockwaves of light, 11,000 photo-multiplier tube detectors surround the cylinder, which contains 50,000 tons of water.
These detectors take an incoming signal of light and multiply it, increasing the signal’s intensity.
Scientists working on a platform above the cylinder are then able to transform the electrical signal from the detectors into useful information about the neutrino.
The Super-Kamiokande is capable of detecting two of the three types of neutrinos: electron and muon neutrinos, but not tau neutrinos.
The number of cones of radiation that these two neutrinos spark in water can be used to tell them apart.
Muon neutrinos spark a single cone, while electron neutrinos spark multiple cones.
A second neutrino detector located 2,100 meters underground in Ontario, Canada, uses a similar design to the Super-Kamiokande in Japan but changes some key features.
The Sudbury Neutrino Observatory (SNO) uses 1,000 tons of heavy water instead of pure water.
Heavy water is so named because the nuclei of its hydrogen atoms contain an extra neutron, making them “heavy.” A “heavy” hydrogen is called deuterium.
The heavy water is housed in a large, acrylic, spherical tank, which is itself surrounded by an 18-meter high geodesic dome.
The dome contains 9,600 photomultiplier tube detectors, and surrounding the dome is excess pure water, used to shield the detectors.
The effect of all these differences is that SNO can detect the third type of neutrinos: tau neutrinos.
Previous research at the Super-Kamiokande suggested that neutrinos coming from one side of the earth differed in number compared to those coming from the other side of the earth.
Considering that neutrinos do not interact with any matter, this was puzzling to scientists. They hypothesized that somehow, the neutrinos must have changed forms.
Indeed, as research at SNO indicates, the missing muon neutrinos observed by the Super-Kamiokande were transformed into tau neutrinos.
Armed with this knowledge and the applications of quantum physics, McDonald and Kajita were able to conclude that the different neutrinos have different masses. | {"extraction_info": {"found_math": false, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.8141091465950012, "perplexity": 1434.3140379156987}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2017-17/segments/1492917122955.76/warc/CC-MAIN-20170423031202-00071-ip-10-145-167-34.ec2.internal.warc.gz"} |
https://www.maplesoft.com/support/help/maple/view.aspx?path=MaplePortal&term=portal&L=E | The Maple Portal is designed as a starting place for any Maple user. Maple's Tutorials will help you get started with Maple, learn about the key tools available in Maple, and lead you through a series of problems. From here, investigate more detailed topics in the Portals for Engineers, Students, and Math Educators. - Maple Programming Help | {"extraction_info": {"found_math": false, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 1, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.8562999963760376, "perplexity": 1458.3975110180854}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2019-18/segments/1555578529606.64/warc/CC-MAIN-20190420100901-20190420122901-00528.warc.gz"} |
https://concurnas.com/docs/methodReferences.html | # Method References?
Method references are an extremely useful part of functional programming which are included in Concurnas. They allow one to pass a reference to a method around one's program in the same way that one would pass data via objects or primitive types. Note that in this section we use the terms 'function' and 'method' interchangeably as for the most part function and method references behave identically.
## Basic Method References?
We create a function or method reference by using the & operator:
def myfunction(an int, bn int) => an + bn
funcRef1 (int, int) int = myfunction&(int, int)
Above, funcRef1 is a method reference type (int, int) int because we have chosen to not bind either of the two input arguments to the function when making our reference. We can call the method reference, like a normal function:
result = funcRef1(1, 2)
//result == 3
We can even make method references to method references:
frefTofref = funcRef1&(int, int)
We can choose to bind any or all of the inputs arguments to the function as follows:
partial (int) int = myfunction&(int, 10)
full () int = myfunction&(2, 2)
//now lets use them...
result = [partial(10), full()]
//result == [20 4]
Notice how above the type returned from & is contingent on which input arguments have been bound. Bounded input arguments do not show up in the method reference type.
If there exists only one function matching the name of the function we're trying to make a method reference for in scope, and we wish to not bind any input arguments (if there are any), then we can forgo having to specify the types to leave unbound and simply create our method reference as follows:
funcRef (int, int) int = myfunction&
Sometimes there is ambiguity in terms of type names and variable names. Though this is bad practice one can resolve this ambiguity by using an ? to indicate that we wish to leave the argument with matching typename unbounded:
class MyClass()
def bounce(an MyClass) => an
def bounce(an int) => an
MyClass = 99
ref = bounce(? MyClass)//directed call to first version of function
If we hadn't used the ? above then the variable MyClass would have attempted to have been passed to the function reference.
Another neat approach we can take when defining method references (particularly for overloaded method definitions differing only in the number of arguments they have) is to simply use a comma to indicate that we wish a parameter to remain unbounded:
def myFunction(a int, b int, c int) => a+b*c
fref (int, int) int = myFunction&(, 45, )
call = fref(1, 3)//equvilent to calling: myFunction(1, 45, 3)
## Method references for instance objects?
Things become slightly more complex when we are dealing with method references on instance objects. We must decide if we wish to bind the method reference to a specific instance object at the point of definition of the method reference or not. We call these two forms, bounded and unbounded method references. The key difference is that only bounded method references may be invoked. Say we have the following class:
class MyClass(cnt int){
def incMany(bywhat int){
cnt += bywhat
}
}
Let's create a bounded method reference:
instObj = new MyClass(10)
boundedMethodRef = instObj.incMany&
We can see above that when creating boundedMethodRef we are referencing an instance object instObj of MyClass - as such the method reference held by variable boundedMethodRef is said to be bound to object instObj. When we call boundedMethodRef it is though we are calling incMany on instObj.
We can create an unbounded method reference in the following way:
methodRef = MyClass.incMany&
The above method reference methodRef cannot be called by itself as it is not bound to an instance object of type MyClass. Attempting to invoke methodRef in its unbound state will result in an com.concurnas.bootstrap.lang.LambdaException exception being thrown.
In order render methodRef callable, it first needs to be transformed into a bounded method reference. This is achieved by calling bind on the method reference:
instObj = new MyClass(10)
methodRef.bind(instObj)
Now we can invoke methodRef.
## References to Constructors?
In Concurnas, method references are not limited to just methods, but they can be applied to constructors as well. Let's take a class:
class MyClass(cnt int){
this(an int, ab int){
this(an + ab)
}
def incMany(bywhat int){
cnt += bywhat
}
override toString() => "MyClass({cnt})"
}
We can create a constructor reference, which looks very much like a method reference, in the normal manner as follows:
refToCon = MyClass&(int, int)
instanceObj MyClass = refToCon(12, 13)
But, what if we wish to defer the choice of constructor called to the caller of the reference? In this case we can use the following syntax in order to create a constructor reference, with special type: (*) X where X is the type of the instance object being created. Example:
refToCon ( * ) MyClass = MyClass& //this will defer the choice of constructor to call until later
"result: " + refToCon(12, 13)//at this point the constructor to call is determined
This may seem to be of little use, since in the example above one could just call new MyClass(12, 13) to have the same effect. But consider the application with locally defined classes - which by nature cannot have instance objects of them created via the new operator outside of their defined scope. We can use this feature of Concurnas to create instance objects of locally defined classes outside of their defined scope:
def creator(){
class MiniClass (a String){
this(a int) { this(""+a) }
override toString() => "MiniClass: " + a
}
//MiniClass cannot be created outside of the scope of creator, unless we use a constructor reference as par below...
return MiniClass&
}
miniCRef = creator()
istObj = miniCRef('hi')
## Lambdas?
Lambdas are a nice feature of Concurnas from functional programming which allow us to create functions which do not have identifiers. When a lambda is created its type is that of a Method reference. Lambdas are created in the same way as functions but they have no identifier (no name). For example:
plusOne (int) int = def (a int) int { return a + 1 }
They can be invoked just like normal method references:
res = plusOne(2)
//res == 3
We can compact the lambda definitions in the normal manner, the following are all equivalent:
plusOne (int) int = def (a int) int { return a + 1 }
plusOne = def (a int){ return a + 1 }
plusOne = def (a int){ a + 1 }
plusOne = def (a int) => a + 1
To see how these are useful, lets define our own map function operating on an array of integers:
def myMap(opOn int[], func (int) int) => func(opOn^)
data = [1 2 3 4]
res = myMap(data, def (a int) => a+1)
//res == [2 3 4 5]
### Zero argument lambdas?
Concurnas has special additional support for zero argument lambdas. An expression which evaluates to the return type of a zero argument lambda may be used in place of a lambda definition. For example, this is perfectly valid code:
athing () int = {5**2}
res = [athing(), athing(), athing()]
//res == [25, 25, 25]
In the above case the 5**2 expression block will be automatically "upgraded" to a lambda, taking no arguments and returning an int so as to match the left hand side assignment type. Note that the expression will be fully evaluated on every call to the lambda. To see this in action see the following example:
counter = 0
athing () int = 5**counter++
res = [counter, athing(), athing(), athing(), counter]
//res == [0, 1, 5, 25, 3]
Here we see that the counter is incremented on every call.
The above automatic "upgrading" may occur at any point where the zero argument lambda is required. For instance, in a function call:
counter = 0
def perform(athing () int) => [counter, athing(), athing(), athing(), counter]
res = perform(5**counter++)
//res == [0, 1, 5, 25, 3]
## Anonymous lambdas?
Anonymous lambdas provide a convenient shorthand for defining lambdas. The following definitions are functionally identical:
mul2v1 = def (a int) int => a*2 //expanded 'normal' lambda definition
mul2v2 (int) int = (a int) => a*2 //compact lambda definition with return type inference
mul2v3 (int) int = a => a*2 //fully compact lambda definition with return and argument type inference
With mul2v2 we see a more compact form of the same lambda definition as mul2v1.
The final definition mul2v3 is most interesting as only the input variable names to the lambda are defined. Their types, along with the return type, are left to be inferred based on the context in which the lambda is defined, which, in this case is on the right hand side of an assignment statement for a function type taking one integer and returning another.
Another common context in which anonymous lambdas are defined are in arguments to function invocations:
class MyNumberHolder(~a int){
def apply(operation (int) int) => operation(a)//apply takes a lambda and applies to to the held value of a
}
mnh = MyNumberHolder(12)
res = mnh.apply(a => a+100)//we define a lambda in compact form
//res == 112
Note that we must be able to infer the type of the lambda in order to be able to use the compact form. The following will resolve in a compile time error since we don't know what they type of mul is:
mul = a => a.operation(5, "n")
### SAM types?
SAM types, or Single Abstract Method types are traits (or interfaces if referencing Java code) which define only one single abstract method. Concurnas performs a neat trick where we can map a lambda we have created, in compact form, to an instance of a SAM type. Some alternative methods to using a lambda are to implement our solution as either an instance object, or an anonymous class, but as you will see, the lambda is the preferred approach for its compactness.
trait Operator{//This is a SAM type as there is only one method defined which is abstract
def perform(arg int, arg2 int) int
}
class MyNumberHolder(~a int){
def apply(b int, operator Operator) => operator.perform(a, b)
}
mnh = MyNumberHolder(12)
res = mnh.apply(50, a, b => a + b)// second parameter is used to generate an Operator instance
//res == 62
In the above example, an instance of the Operator mixin is generated from the addition lambda defined in order to satisfy the second argument of the apply method. Note that we don't have to use the compact lambda form, the full form is acceptable for this purpose as well.
This makes using the Java sdk stream library possible in Concurnas. For example:
mylist = [1, 2, 3, 4, 5, 6, 7, 8]
res = mylist.stream().map(a =>a+10).collect(java.util.stream.Collectors.toList())
//res == [11, 12, 13, 14, 15, 16, 17, 18]
Without the compact syntax and SAM type support we would have to write code like the following:
mixin Operator{//This is a SAM type as there is only one method defined which is abstract
def perform(arg int, arg2 int) int
}
class MyNumberHolder(~a int){
def apply(b int, operator Operator) => operator.perform(a, b)
}
mnh = MyNumberHolder(12)
myOperator = class ~ Operator{//define a class implementing the mixin Operator
def perform(arg int, arg2 int) int = >arg + arg2
}
res = mnh.apply(50, new myOperator())
//res == 62
The compact lambda definition is far more convenient than this alternative, and the compact form comes with no performance penalty!
### SAM types with a zero argument abstract method?
Just as with zero argument lambdas Concurnas have special additional support for SAM types whose single abstract method takes no arguments. An expression which evaluates to the return type of method can be used in place of a lambda definition as above. As such we are able to write code such as the following:
trait ExeCounter{//this is a SAM type
counter int
def toexe() int//zero arg abstract method
public def invoke() int[] => [counter++ toexe()]
}
athing ExeCounter = 5
res = [athing(), athing(), athing()]
//res == [[0 5], [1 5], [2 5]] | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 1, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.2736651599407196, "perplexity": 2911.4209347915075}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 20, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2020-16/segments/1585370496227.25/warc/CC-MAIN-20200329201741-20200329231741-00358.warc.gz"} |
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### Lyubeznik numbers of almost complete intersection and linked ideals. (English)Zbl 1491.13019
MSC: 13C40 13D45 13P10
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### The six functors for Zariski-constructible sheaves in rigid geometry. (English)Zbl 1495.14036
MSC: 14G22 14F20 14F06
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### Matroid psi classes. (English)Zbl 1493.05059
MSC: 05B35 52B40 14N35
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### Stable pair invariants of local Calabi-Yau 4-folds. (English)Zbl 1490.14090
MSC: 14N35 14J32 14J35
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### Rigidity of CR morphisms. (English)Zbl 1487.32163
MSC: 32S20 32V99
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### Sheaves of $$E$$-infinity algebras and applications to algebraic varieties and singular spaces. (English)Zbl 07462176
MSC: 32S35 55N33
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### When are there enough projective perverse sheaves? (English)Zbl 1475.55008
MSC: 55N33 18G80
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### Maximal Cohen-Macaulay complexes and their uses: a partial survey. (English)Zbl 1498.13034
Peeva, Irena (ed.), Commutative algebra. Expository papers dedicated to David Eisenbud on the occasion of his 75th birthday. Cham: Springer. 475-500 (2021).
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### Mellin operators in weighted corner spaces. (English)Zbl 07620482
Manuilov, Vladimir M. (ed.) et al., Differential equations on manifolds and mathematical physics. Dedicated to the memory of Boris Sternin. Selected papers based on the presentations of the conference on partial differential equations and applications, Moscow, Russia, November 6–9, 2018. Cham: Birkhäuser. Trends Math., 287-313 (2021).
MSC: 35S35 35J70
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### Loops in surfaces and star-fillings. (English)Zbl 1497.55009
Alekseev, Anton (ed.) et al., Representation theory, mathematical physics, and integrable systems. In honor of Nicolai Reshetikhin. Cham: Birkhäuser. Prog. Math. 340, 617-643 (2021).
MSC: 55N33 55P35
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### Localized Chern characters for 2-periodic complexes and virtual cycles. (English)Zbl 1497.14009
Jarvis, Tyler J. (ed.) et al., Singularities, mirror symmetry, and the gauged linear sigma model. Summer school ‘Crossing the walls in enumerative geometry’, Snowbird, UT, USA, May 21 – June 1, 2018. Providence, RI: American Mathematical Society (AMS). Contemp. Math. 763, 117-129 (2021).
MSC: 14C17 14N35 14-02
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### Localization and mirror symmetry. (English)Zbl 1497.14114
Jarvis, Tyler J. (ed.) et al., Singularities, mirror symmetry, and the gauged linear sigma model. Summer school ‘Crossing the walls in enumerative geometry’, Snowbird, UT, USA, May 21 – June 1, 2018. Providence, RI: American Mathematical Society (AMS). Contemp. Math. 763, 43-65 (2021).
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### A new deterministic method for computing Milnor number of an ICIS. (English)Zbl 07497966
Boulier, François (ed.) et al., Computer algebra in scientific computing. 23rd international workshop, CASC 2021, Sochi, Russia, September 13–17, 2021. Proceedings. Cham: Springer. Lect. Notes Comput. Sci. 12865, 391-408 (2021).
MSC: 68W30
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### Lefschetz section theorems for tropical hypersurfaces. (Théorème de la section hyperplane de Lefschetz pour les hypersurfaces tropicales.) (English. French summary)Zbl 07480737
MSC: 14T15 58A14 32S60
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### Cohomological methods in intersection theory. (English)Zbl 1478.14003
Neumann, Frank (ed.) et al., Homotopy theory and arithmetic geometry – motivic and Diophantine aspects. LMS-CMI research school, London, UK, July 9–13, 2018. Lecture notes. Cham: Springer. Lect. Notes Math. 2292, 49-105 (2021).
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### An introduction to $$\mathbb{A}^1$$-enumerative geometry. Based on lectures by Kirsten Wickelgren delivered at the LMS-CMI research school “Homotopy theory and arithmetic geometry – motivic and Diophantine aspects”. (English)Zbl 1478.14002
Neumann, Frank (ed.) et al., Homotopy theory and arithmetic geometry – motivic and Diophantine aspects. LMS-CMI research school, London, UK, July 9–13, 2018. Lecture notes. Cham: Springer. Lect. Notes Math. 2292, 11-47 (2021).
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### Cohomology of the moduli space of non-hyperelliptic genus four curves. (Cohomologie de l’espace de modules des courbes non hyperelliptique de genre quatre.) (English. French summary)Zbl 1487.14101
MSC: 14L24 14F43 14H10
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### Intersection homology. (English)Zbl 1486.14002
Cisneros-Molina, José Luis (ed.) et al., Handbook of geometry and topology of singularities II. Cham: Springer. 223-308 (2021).
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### A Riemann-Roch type theorem for twisted fibrations of moment graphs. (English)Zbl 1486.14062
MSC: 14L30 14C17 14M15
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### Fundamental classes in motivic homotopy theory. (English)Zbl 1483.14040
MSC: 14F42 14C17 19E15
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### Milnor-Witt homotopy sheaves and Morel generalized transfers. (English)Zbl 1484.14047
MSC: 14F42 14C17 14C35
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### A support theorem for the Hitchin fibration: the case of $$\operatorname{GL}_n$$ and $$K_C$$. (English)Zbl 1476.14068
MSC: 14H60 14C17 14F06
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### Localization of complete intersections. (English)Zbl 1481.13038
MSC: 13H10 13D02
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### Virtual classes of $$\mathbb{G}_{\mathrm{m}}$$-gerbes. (English)Zbl 07428812
MSC: 14C17 14N35
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### Localization of IC-complexes on Kashiwara’s flag scheme and representations of Kac-Moody algebras. (English)Zbl 1481.17033
MSC: 17B67 14M15
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### Explicit Poincaré duality in the cohomology ring of the $$\mathrm{SU}(2)$$ character variety of a surface. (English)Zbl 1475.14100
MSC: 14M35 55N45 14D20
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### Analysis on regular corner spaces. (English)Zbl 1478.35111
MSC: 35J25 35S35 35J70
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### $$\hbar$$-deformed Schubert calculus in equivariant cohomology, $$K$$-theory, and elliptic cohomology. (English)Zbl 1468.55002
Fernández de Bobadilla, Javier (ed.) et al., Singularities and their interaction with geometry and low dimensional topology. In honor of András Némethi on the occasion of his 60th birthday. Selected papers based on the presentations at the conference “Némethi60: geometry and topology of singularities”, Budapest, Hungary, May 27–31, 2019. Basel: Birkhäuser/Springer. Trends Math., 73-96 (2021).
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### Corner operators with symbol hierarchies. (English)Zbl 1478.35249
MSC: 35S15 35S35 35J70
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### Perverse sheaves on semi-abelian varieties. (English)Zbl 1470.32089
MSC: 32S60 14F17 55N25
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### Resolvent, heat kernel, and torsion under degeneration to fibered cusps. (English)Zbl 1476.58001
Memoirs of the American Mathematical Society 1314. Providence, RI: American Mathematical Society (AMS) (ISBN 978-1-4704-4422-8/pbk; 978-1-4704-6466-0/ebook). v, 126 p. (2021).
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### Witten’s conjecture and recursions for $$\kappa$$ classes. (English)Zbl 1466.14059
MSC: 14N10 14N35
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### Decomposition theorem and torus actions of complexity one. (English)Zbl 1464.32047
MSC: 32S60 14L30 14M25
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### A de Rham model for complex analytic equivariant elliptic cohomology. (English)Zbl 1472.14027
MSC: 14F40 14F43 55N34
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https://courses.lumenlearning.com/ivytech-collegealgebra/chapter/use-factoring-to-%EF%AC%81nd-zeros-of-polynomial-functions/ | ## Use factoring to find zeros of polynomial functions
Recall that if f is a polynomial function, the values of x for which $f\left(x\right)=0$ are called zeros of f. If the equation of the polynomial function can be factored, we can set each factor equal to zero and solve for the zeros.
We can use the method of factoring the polynomial function and setting each factor equal to zero to find x-intercepts because at the x-intercepts we find the input values when the output value is zero. For general polynomials, this can be a challenging prospect. While quadratics can be solved using the relatively simple quadratic formula, the corresponding formulas for cubic and fourth-degree polynomials are not simple enough to remember, and formulas do not exist for general higher-degree polynomials. Consequently, we will limit ourselves to three cases in this section:
1. The polynomial can be factored using known methods: greatest common factor and trinomial factoring.
2. The polynomial is given in factored form.
3. Technology is used to determine the intercepts.
### How To: Given a polynomial function f, find the x-intercepts by factoring.
1. Set $f\left(x\right)=0$.
2. If the polynomial function is not given in factored form:
1. Factor out any common monomial factors.
2. Factor any factorable binomials or trinomials.
3. Set each factor equal to zero and solve to find the $x\text{-}$ intercepts.
### Example 2: Finding the x-Intercepts of a Polynomial Function by Factoring
Find the x-intercepts of $f\left(x\right)={x}^{6}-3{x}^{4}+2{x}^{2}$.
We can attempt to factor this polynomial to find solutions for $f\left(x\right)=0$.
$\begin{cases}{x}^{6}-3{x}^{4}+2{x}^{2}=0 \hfill & \text{Factor out the greatest common factor}. \hfill \\ \text{ }{x}^{2}\left({x}^{4}-3{x}^{2}+2\right)=0\hfill & \text{Factor the trinomial}.\hfill \\ {x}^{2}\left({x}^{2}-1\right)\left({x}^{2}-2\right)=0\hfill & \text{Set each factor equal to zero}.\hfill \end{cases}$
$\begin{cases}\hfill & \hfill & \left({x}^{2}-1\right)=0\hfill & \hfill & \left({x}^{2}-2\right)=0 \\ {x}^{2}=0 \hfill & \text{or}\hfill &{x}^{2}=1\hfill & \text{or}\hfill &{x}^{2}=2 \\ x=0\hfill & \hfill & x=\pm 1\hfill & \hfill & x=\pm \sqrt{2}\hfill \end{cases}$
Figure 3
This gives us five x-intercepts: $\left(0,0\right),\left(1,0\right),\left(-1,0\right),\left(\sqrt{2},0\right)$, and $\left(-\sqrt{2},0\right)$. We can see that this is an even function.
### Example 3: Finding the x-Intercepts of a Polynomial Function by Factoring
Find the x-intercepts of $f\left(x\right)={x}^{3}-5{x}^{2}-x+5$.
### Solution
Find solutions for $f\left(x\right)=0$ by factoring.
$\begin{cases} \text{ }{x}^{3}-5{x}^{2}-x+5=0\hfill & \text{Factor by grouping}.\hfill \hfill \\ \text{ }{x}^{2}\left(x - 5\right)-\left(x - 5\right)=0\hfill & \text{Factor out the common factor}.\hfill \\ \text{ }\left({x}^{2}-1\right)\left(x - 5\right)=0\hfill & \text{Factor the difference of squares}.\hfill \\ \left(x+1\right)\left(x - 1\right)\left(x - 5\right)=0\hfill & \text{Set each factor equal to zero}.\hfill \end{cases}$
$\begin{cases}x+1=0\hfill & \text{or}\hfill & x - 1=0\hfill & \text{or}\hfill & x - 5=0\hfill \\ x=-1\hfill & \hfill & x=1\hfill & \hfill & x=5\hfill \end{cases}$
Figure 4
There are three x-intercepts: $\left(-1,0\right),\left(1,0\right)$, and $\left(5,0\right)$.
### Example 4: Finding the y– and x-Intercepts of a Polynomial in Factored Form
Find the y– and x-intercepts of $g\left(x\right)={\left(x - 2\right)}^{2}\left(2x+3\right)$.
### Solution
The y-intercept can be found by evaluating $g\left(0\right)$.
$\begin{cases}g\left(0\right)={\left(0 - 2\right)}^{2}\left(2\left(0\right)+3\right)\\ =12\end{cases}$
So the y-intercept is $\left(0,12\right)$.
The x-intercepts can be found by solving $g\left(x\right)=0$.
${\left(x - 2\right)}^{2}\left(2x+3\right)=0$
$\begin{cases}{\left(x - 2\right)}^{2}=0\hfill & \hfill & \hfill & \hfill & \left(2x+3\right)=0\hfill \\ \text{ }x - 2=0\hfill & \hfill & \text{or}\hfill & \hfill & \text{ }x=-\frac{3}{2}\hfill \\ \text{ }x=2\hfill & \hfill & \hfill & \hfill & \hfill \end{cases}$
So the x-intercepts are $\left(2,0\right)$ and $\left(-\frac{3}{2},0\right)$.
### Analysis of the Solution
We can always check that our answers are reasonable by using a graphing calculator to graph the polynomial as shown in Figure 5.
Figure 5
### Example 5: Finding the x-Intercepts of a Polynomial Function Using a Graph
Find the x-intercepts of $h\left(x\right)={x}^{3}+4{x}^{2}+x - 6$.
### Solution
This polynomial is not in factored form, has no common factors, and does not appear to be factorable using techniques previously discussed. Fortunately, we can use technology to find the intercepts. Keep in mind that some values make graphing difficult by hand. In these cases, we can take advantage of graphing utilities.
Looking at the graph of this function, as shown in Figure 6, it appears that there are x-intercepts at $x=-3,-2$, and 1.
Figure 6
We can check whether these are correct by substituting these values for x and verifying that
$h\left(-3\right)=h\left(-2\right)=h\left(1\right)=0$.
Since $h\left(x\right)={x}^{3}+4{x}^{2}+x - 6$, we have:
$\begin{cases}h\left(-3\right)={\left(-3\right)}^{3}+4{\left(-3\right)}^{2}+\left(-3\right)-6=-27+36 - 3-6=0\hfill \\ h\left(-2\right)={\left(-2\right)}^{3}+4{\left(-2\right)}^{2}+\left(-2\right)-6=-8+16 - 2-6=0\hfill \\ \text{ }h\left(1\right)={\left(1\right)}^{3}+4{\left(1\right)}^{2}+\left(1\right)-6=1+4+1 - 6=0\hfill \end{cases}$
Each x-intercept corresponds to a zero of the polynomial function and each zero yields a factor, so we can now write the polynomial in factored form.
$\begin{cases}h\left(x\right)={x}^{3}+4{x}^{2}+x - 6\hfill\hfill \\ \text{ }=\left(x+3\right)\left(x+2\right)\left(x - 1\right)\hfill \end{cases}$
### Try It 1
Find the y– and x-intercepts of the function $f\left(x\right)={x}^{4}-19{x}^{2}+30x$.
Solution | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.7255061268806458, "perplexity": 622.3619974973607}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2019-47/segments/1573496671548.98/warc/CC-MAIN-20191122194802-20191122223802-00103.warc.gz"} |
http://math.stackexchange.com/questions/47171/term-for-tetrahedron-with-three-right-angles-at-a-point | # Term for Tetrahedron with Three Right Angles at a Point
Is there a name for the tetrahedron/pyramid (four vertices, four triangular faces, six edges) where three edges meet orthogonally at a point? Three of the faces are right triangles.
Another description: taking $\vec e_1,\vec e_2,\vec e_3$ as the standard basis vectors of $\mathbb{R}^3$, the vertices are $\vec 0,c_1\vec e_1,c_2\vec e_2,c_3\vec e_3$. The faces are composed of the coordinate planes with the plane $x/c_1 + y/c_2 + z/c_3 = 1$.
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In Coxeter's book it is called an orthoscheme. – Will Jagy Jun 23 '11 at 15:37
I've also seen this figure just called a 'right tetrahedron', by analogy with 'right triangle', and that's probably the first name that I would use for it in informal math writing. – Steven Stadnicki Jun 23 '11 at 16:30
According to Wolfram's Mathworld, it's called a trirectangular tetrahedron.
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A right-cornered tetrahedron.
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Any solid polytope of the form $\sum_{i = 1}^{n} \frac{x_i}{a_i} \leq 1$, where $a_i > 0$ is called a solid, orthotopal, simplicial $n$-polytope and can also be written as the convex hull $\mathbf{conv} \{ \mathbf{0}, a_1 \mathbf{e}_1, \dots, a_n \mathbf{e}_n \}$. For $n = 3$, it is called a solid trirectangular tetrahedron. If you mean the boundary complex, then simply trirectangular tetrahedron is fine. | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.8593742847442627, "perplexity": 432.9986434889864}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2014-10/segments/1394011263617/warc/CC-MAIN-20140305092103-00079-ip-10-183-142-35.ec2.internal.warc.gz"} |
http://etna.ricam.oeaw.ac.at/volumes/2001-2010/vol17/abstract.php?vol=17&pages=11-75 | ## Collocation methods for Cauchy singular integral equations on the interval
P. Junghanns and A. Rogozhin
### Abstract
In this paper we consider polynomial collocation methods for the numerical solution of a singular integral equation over the interval, where the operator of the equation is supposed to be of the form $aI + b \mu^{-1} S \mu I+K$ with $S$ the Cauchy singular integral operator, with piecewise continuous coefficients $a$ and $b\,,$ and with a Jacobi weight $\mu\,.$ $K$ denotes an integral operator with a continuous kernel function. To the integral equation we apply two collocation methods, where the collocation points are the Chebyshev nodes of the first and second kind and where the trial space is the space of polynomials multiplied by another Jacobi weight. For the stability and convergence of this collocation scheme in weighted $L^2$-spaces, we derive necessary and sufficient conditions. Moreover, we discuss stability of operator sequences belonging to algebras generated by the sequences of the collocation methods for the above described operators. Finally, the so-called splitting property of the singular values of the sequences of the matrices of the discretized equations is proved.
Full Text (PDF) [526 KB], BibTeX
### Key words
Cauchy singular integral equation, polynomial collocation method, stability, singular values, splitting property.
### AMS subject classifications
45L10, 65R20, 65N38.
### Links to the cited ETNA articles
[7] Vol. 14 (2002), pp. 79-126 P. Junghanns and A. Rathsfeld: A polynomial collocation method for Cauchy singular integral equations over the interval | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.9828487038612366, "perplexity": 443.9630167972315}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2019-39/segments/1568514574084.88/warc/CC-MAIN-20190920221241-20190921003241-00446.warc.gz"} |
http://www.koreascience.or.kr/article/ArticleFullRecord.jsp?cn=DBSHBB_2008_v45n3_859 | THE GEOMETRY OF THE DIRICHLET MANIFOLD
Title & Authors
THE GEOMETRY OF THE DIRICHLET MANIFOLD
Zhong, Fengwei; Sun, Huafei; Zhang, Zhenning;
Abstract
In the present paper, we investigate the geometric structures of the Dirichlet manifold composed of the Dirichlet distribution. We show that the Dirichlet distribution is an exponential family distribution. We consider its dual structures and give its geometric metrics, and obtain the geometric structures of the lower dimension cases of the Dirichlet manifold. In particularly, the Beta distribution is a 2-dimensional Dirich-let distribution. Also, we construct an affine immersion of the Dirichlet manifold. At last, we give the e-flat hierarchical structures and the orthogonal foliations of the Dirichlet manifold. All these work will enrich the theoretical work of the Dirichlet distribution and will be great help for its further applications.
Keywords
Dirichlet manifold$\small{{\alpha}}$-geometric structures;foliation;immersion;
Language
English
Cited by
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S. Amari and H. Nagaoka, Methods of Information Geometry, Translated from the 1993 Japanese original by Daishi Harada. Translations of Mathematical Monographs, 191. American Mathematical Society, Providence, RI; Oxford University Press, Oxford, 2000
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F. Zhong, H. Sun, and Z. Zhang, Information geometry of the Beta distribution, preprint | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 1, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.9361976385116577, "perplexity": 1067.6997417818623}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2016-44/segments/1476988721405.66/warc/CC-MAIN-20161020183841-00131-ip-10-171-6-4.ec2.internal.warc.gz"} |
https://pub.uni-bielefeld.de/publication/1640104 | # ON NONSTANDARD COUPLINGS AMONG THE ELECTROWEAK VECTOR BOSONS
GROSSE-KNETTER C, KUSS I, Schildknecht D (1995)
PHYSICS LETTERS B 358(1-2): 87-94.
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Application of a Stueckelberg transformation allows one to connect various Lagrangians which have been independently proposed for non-standard couplings. We discuss the reduction of the number of independent parameters in the Lagrangian and compare symmetry arguments with dimensional arguments.
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GROSSE-KNETTER C, KUSS I, Schildknecht D. ON NONSTANDARD COUPLINGS AMONG THE ELECTROWEAK VECTOR BOSONS. PHYSICS LETTERS B. 1995;358(1-2):87-94.
GROSSE-KNETTER, C., KUSS, I., & Schildknecht, D. (1995). ON NONSTANDARD COUPLINGS AMONG THE ELECTROWEAK VECTOR BOSONS. PHYSICS LETTERS B, 358(1-2), 87-94. doi:10.1016/0370-2693(95)01022-I
GROSSE-KNETTER, C., KUSS, I., and Schildknecht, D. (1995). ON NONSTANDARD COUPLINGS AMONG THE ELECTROWEAK VECTOR BOSONS. PHYSICS LETTERS B 358, 87-94.
GROSSE-KNETTER, C., KUSS, I., & Schildknecht, D., 1995. ON NONSTANDARD COUPLINGS AMONG THE ELECTROWEAK VECTOR BOSONS. PHYSICS LETTERS B, 358(1-2), p 87-94.
C. GROSSE-KNETTER, I. KUSS, and D. Schildknecht, “ON NONSTANDARD COUPLINGS AMONG THE ELECTROWEAK VECTOR BOSONS”, PHYSICS LETTERS B, vol. 358, 1995, pp. 87-94.
GROSSE-KNETTER, C., KUSS, I., Schildknecht, D.: ON NONSTANDARD COUPLINGS AMONG THE ELECTROWEAK VECTOR BOSONS. PHYSICS LETTERS B. 358, 87-94 (1995).
GROSSE-KNETTER, C, KUSS, I, and Schildknecht, Dieter. “ON NONSTANDARD COUPLINGS AMONG THE ELECTROWEAK VECTOR BOSONS”. PHYSICS LETTERS B 358.1-2 (1995): 87-94.
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## Beautiful_Lier96 Group Title how to simplify a radical expression. ex: Simplify the prob 3Sqrrt(-243x^3y^10) i already know nSqrrt(a) * nSqrrt(B) = nSqrrt(AB) one year ago one year ago Edit Question Delete Cancel Submit
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1. satellite73
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ok so $$\sqrt[3]{x^3}=x$$ for a start
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2. satellite73
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and since $$243=3^5$$ we have $$\sqrt[3]{3^5}=3\sqrt[3]{3^2}$$
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finally $$\sqrt[3]{y^{10}}=3\sqrt[3]{y}$$
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https://www.physicsforums.com/threads/the-sum-of-series-involving-cosine.289076/ | # The sum of series involving cosine
1. Feb 1, 2009
### thanksie037
1. The problem statement, all variables and given/known data
Find the sum of the series s(x) = 1 +cos(x)+ (cos2x)/2!+(cos3x)/3!...
2. Relevant equations
3. The attempt at a solution
2. Feb 1, 2009
### gabbagabbahey
Hi thanksie, what have you tried? What methods have you learned? Are you allowed to compare it to other known series?
3. Feb 1, 2009
### thanksie037
Hi, Yes we can compare it to known series. I've tried a comparison with the harmonic series and the expansion for e^x looks promising. I'm just not sure how to get started.
4. Feb 1, 2009
### gabbagabbahey
Comparing it to the series for e^x sounds good to me.....try writing $\cos(nx)$ in terms of complex exponentials....what does that give you?
5. Feb 1, 2009
### thanksie037
would x= cosnx? is there a property for cosine where (cos x)^n=cos nx ?
6. Feb 1, 2009
### gabbagabbahey
Not quite...try writing $\cos(nx)$ in terms of complex exponentials....what do you get?
7. Feb 1, 2009
### thanksie037
Do you mean:
x^ni=cos nx + sin nx?
8. Feb 1, 2009
### gabbagabbahey
Huh?! Why on Earth would you think that were true?
Have you not seen the formulas $$e^{i\theta}=\cos\theta+i\sin\theta$$ and $$\cos\theta=\frac{e^{i\theta}+e^{-i\theta}}{2}$$ before?
9. Feb 1, 2009
### thanksie037
sorry i was using that first one. i was confused as to what you meant with cos nx.
using the second one makes a lot more sense. are you saying i should:
cos n(theta) = (e^ni(theta) +e^-ni(theta))/2
10. Feb 1, 2009
### thanksie037
and how do i even find the sum of this series. i only know how to find a sum of a geometric series...i dont know how to deal with the factorial
11. Feb 1, 2009
### gabbagabbahey
Yes, so now you have
$$1+\cos(x)+\frac{\cos(2x)}{2!}+\ldots=\sum_{n=0}^{\infty} \frac{\cos(nx)}{n!}=\frac{1}{2}\sum_{n=0}^{\infty} \frac{e^{i n x}+e^{-i n x}}{n!}$$
correct?
Try breaking it into two separate sums:
$$\frac{1}{2}\sum_{n=0}^{\infty} \frac{e^{i n x}+e^{-i n x}}{n!}=\frac{1}{2}\sum_{n=0}^{\infty} \frac{e^{i n x}}{n!}+\frac{1}{2}\sum_{n=0}^{\infty} \frac{e^{-i n x}}{n!}$$
Now use the fact that $$e^{n\theta}=\left(e^{\theta}\right)^n$$ and compare each sum to the series for e^u.
12. Feb 1, 2009
### thanksie037
That makes sense. Thanks for all your help.
One more unrelated quick question:
do the series n/(n+1) and n^2/(n^2+1)converge or diverge?
13. Feb 1, 2009
### gabbagabbahey
Well, try applying some of the convergence tests that you've learned....
14. Feb 1, 2009
### Gregg
I looked at this and became interested but got stuck.
$e^{ix} = \cos x + i \sin x$
$e^{-ix} = \cos x - i \sin x$
$\cos x = \frac{e^{ix} + e^{-ix}}{2}$
$\displaystyle\sum_{n=0}^\infty \frac{\cos (nx)}{n!} = \displaystyle\sum_{n=0}^\infty \frac{e^{inx} + e^{-inx}}{2n!}$
$\displaystyle\sum_{n=0}^\infty \frac{e^{inx} + e^{-inx}}{2n!} = \displaystyle\sum_{n=0}^\infty \frac{e^{inx}}{2n!} + \displaystyle\sum_{n=0}^\infty \frac{e^{-inx}}{2n!}$
$\displaystyle\sum_{n=0}^\infty \frac{e^{inx} + e^{-inx}}{2n!} = \frac{1}{2} \left[ \displaystyle\sum_{n=0}^\infty \frac{e^{inx}}{n!} + \displaystyle\sum_{n=0}^\infty \frac{e^{-inx}}{n!} \right]$
$e^x = \displaystyle\sum_{n=0}^\infty \frac{x^n}{n!}$
$\displaystyle\sum_{n=0}^\infty \frac{e^{inx}}{n!} = e^{e^{ix}}$
$\displaystyle\sum_{n=0}^\infty \frac{e^{-inx}}{n!} = e^{e^{-ix}}$
$\displaystyle\sum_{n=0}^\infty \frac{e^{inx} + e^{-inx}}{2n!} = \frac{1}{2} \left[e^{e^{-ix}} + e^{e^{ix}} \right]$
Edit: I think this is OK actually.
Last edited: Feb 1, 2009
15. Feb 1, 2009
### thanksie037
yeah I was going to say that's what I got... lots of thanks to gab, I would have put my work in here but I don't know how to use this forum very well.
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# If a runner in a marathon had the 37th fastest time and the 50th slowe
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26 Dec 2014, 08:32
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Tough and Tricky questions: Word Problems.
If a runner in a marathon had the 37th fastest time and the 50th slowest time, how many runners finished the marathon?
A. 83
B. 84
C. 85
D. 86
E. 87
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Re: If a runner in a marathon had the 37th fastest time and the 50th slowe [#permalink]
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26 Dec 2014, 09:55
If the runner finished 37th, there are 36 runners faster than him. If he has the 50th slowest slowest time, there must be 49 runners slower than him.
We can therefore conclude that there are 86 runners in the marathon: 36 faster runners + 49 slower runners + 1 the runner we are asked about.
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Re: If a runner in a marathon had the 37th fastest time and the 50th slowe [#permalink]
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26 Dec 2014, 17:31
Bunuel wrote:
Tough and Tricky questions: Word Problems.
If a runner in a marathon had the 37th fastest time and the 50th slowest time, how many runners finished the marathon?
A. 83
B. 84
C. 85
D. 86
E. 87
Kudos for a correct solution.
# of runners faster than runner x = 36
# of runners slower than runner x = 49
Total runners = 36+49+1(Runner x) = 86
Ans D
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Re: If a runner in a marathon had the 37th fastest time and the 50th slowe [#permalink]
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27 Dec 2014, 01:04
Lets imagine a marathon race. As per question since he is 37th fastest then he has 36 runners ahead of him. Since he is 50th slowest that means 49 runners are behind him.
Total runners=37+50=87. But since the same runner is counted twice we need to subtract 1. hence total runners =87-1=86.
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Re: If a runner in a marathon had the 37th fastest time and the 50th slowe [#permalink]
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27 Dec 2014, 04:07
1
Imagine at the end of the race all the contestants are made to stand in a line as per the time taken to complete the race, fastest being the first and slowest as the last. Then if we count from first he is at 37 position ie he sees 36 ppl in front of him. and if counted from the last he is at 50th position including him. now to this 50 from the last till him we add the other 36 in front of him. hence 50 + 36 = 86
hence D
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Re: If a runner in a marathon had the 37th fastest time and the 50th slowe [#permalink]
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02 Jan 2015, 01:53
37 + 50 - 1 = 86
Refer diagram below (Conceptual)
Attachment:
pos.png [ 5.01 KiB | Viewed 1369 times ]
Addition of forward & reverse position would always given 1 more than the actual quantity
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Re: If a runner in a marathon had the 37th fastest time and the 50th slowe [#permalink]
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08 Jan 2015, 09:31
Bunuel wrote:
Tough and Tricky questions: Word Problems.
If a runner in a marathon had the 37th fastest time and the 50th slowest time, how many runners finished the marathon?
A. 83
B. 84
C. 85
D. 86
E. 87
Kudos for a correct solution.
OFFICIAL SOLUTION:
(D) If the runner had the 37th fastest time that means 36 runners finished before the runner. If the runner had the 50th slowest time that means 49 runners finished after the runner. The total number of runners who finished the marathon is 36 + 1 + 49 = 86.
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Re: If a runner in a marathon had the 37th fastest time and the 50th slowe [#permalink]
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09 Apr 2016, 14:29
36 runners before him_______the runner himself______ 49 runners after him
So total number of runners in the race is 36+1+49 = 86
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Re: If a runner in a marathon had the 37th fastest time and the 50th slowe [#permalink]
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29 Dec 2017, 08:17
Top Contributor
Bunuel wrote:
Tough and Tricky questions: Word Problems.
If a runner in a marathon had the 37th fastest time and the 50th slowest time, how many runners finished the marathon?
A. 83
B. 84
C. 85
D. 86
E. 87
Kudos for a correct solution.
Runner had the 37th fastest time...
So, there are 36 people IN FRONT of the runner
Runner had the 50th slowest time...
So, there are 49 people BEHIND the runner
How many runners finished the marathon?
We have:
- - - - - 49 people-----the runner--------36 people------
So, the TOTAL number of runners = 49 + 1 + 36 = 86
Cheers,
Brent
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Re: If a runner in a marathon had the 37th fastest time and the 50th slowe &nbs [#permalink] 29 Dec 2017, 08:17
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http://mathoverflow.net/questions/47938/what-is-correct-name-of-the-following-construction?answertab=oldest | # What is correct name of the following construction?
Consider an ideal $I=\langle f_1,f_2,\ldots,f_s\rangle$ in the polynomial ring $\mathbb{Q}[x_1,x_2,\ldots,x_n].$ Build the following set $$\{ g_1 f_1+g_1 f_2+\cdots+g_n f_n \},$$ where $g_i$ belongs to the field of fractions $\mathbb{Q}(x_1,x_2,\ldots,x_n)$ and denominators of all $g_i$ does not belong to the ideal $I.$ Is there a special name for this set?
-
This is the maximal ideal in the localization of $S$ at $I$. – Alexander Woo Dec 1 '10 at 20:09
Other than "localization of the module $\left\lbrace f_1,f_2,...,f_s\right\rbrace$ at the complement of the ideal $\left\lbrace f_1,f_2,...,f_s\right\rbrace$"? – darij grinberg Dec 1 '10 at 20:10
Sorry, the brackets should be < > rather than { }. – darij grinberg Dec 1 '10 at 20:10
This is the image of $I$ in the localization $\mathbb Q[x_1,x_2,\dots,x_n]_{I}$.
There is an issue here though. If $I$ is not a prime ideal, then its complement is not multiplicatively closed, and therefore not a good set to invert in a localization. If $I$ is not a prime ideal, then there are some $f, g$ in $I^c$ such that $fg\in I$. Thus, e.g., $\frac{1}{f}\cdot\frac{1}{g}$ becomes a non-allowed coefficient, while $\frac{1}{f}$ and $\frac{1}{g}$ both are.
The set you describe can still be defined, obviously, but it will lack interesting structure. If $I$ is a prime ideal, then your set is the ideal in the localization ring that I describe above. | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 1, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.8819010257720947, "perplexity": 222.85688698566224}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.3, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2015-22/segments/1432207928114.23/warc/CC-MAIN-20150521113208-00135-ip-10-180-206-219.ec2.internal.warc.gz"} |
http://mathoverflow.net/questions/28811/statements-reliant-on-conjectures?sort=oldest | # Statements reliant on conjectures
There are lots of statements that have been conditionally proved on the assumption that the Riemann Hypothesis is true.
What other conjectures have a large number of proven consequences ?
-
What is usually referred to as Lusztig's Conjecture in the modular representation theory of semisimple algebraic groups has been enormously influential, as seen in Jantzen's treatise Representations of Algebraic Groups. It is actually a series of closely related conjectures, from 1979 on, inspired by the (soon proved) Kazhdan-Lusztig Conjecture (1979) on the formal characters of the usually infinite dimensional simple highest weight modules for a complex semisimple Lie algebra: such a character can be written as a $\mathbb{Z}$-linear combination of the known formal characters of Verma modules whose coefficients are values at 1 of Kazhdan-Lusztig polynomials for the Iwahori-Hecke algebra of the Weyl group $W$. The original characteristic $p$ conjecture has a similar flavor, but with the affine Weyl group (whose translations are multiplied by $p$) replacing $W$ and with the essential proviso that $p$ be not too small. It is expected that the Coxeter number of $W$ will be a suitable lower bound, but so far the partial proofs by Andersen-Jantzen-Soergel, Fiebig, and Bezrukavnikov-Mirkovic do not achieve a reasonable bound.
If proved, the conjecture would combine with older results of Curtis and Steinberg to yield all modular irreducible characters of finite groups of Lie type in the defining characteristic (but still with the lower bound on $p$), as well as the formal characters and dimensions of all restricted representations of the Lie algebra of the given semisimple group. Andersen and others have formulated further consequences, in terms of the structure of Weyl modules, the extensions and cohomology of simple or Weyl modules, etc. (Adapted to general linear groups, there are also implications for modular characters of symmetric groups.) The later conjectures of Lusztig, proved for large enough $p$ in a preprint by Bezrukavnikov and Mirkovic, go further with the non-restricted Lie algebra representations as well in a unified geometric setting which promises further applications.
ADDED: I should point out that many special cases of the more general results which would follow from Lusztig's Conjecture have in fact been verified, but usually by computational or somewhat ad hoc methods. Plus the existing proofs of the conjecture itself for "large enough" primes, which don't seem improvable without new methods.
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Set theory is of course completely saturated with this feature, since the independence phenomenon means that a huge proportion of the most interesting natural set-theoretic questions turn out to be independent of the basic ZFC axioms. Thus, most of the interesting work in set theory is about the relations beteween these various independent statements. They typically have the form of implications assuming the truth of a hypothesis not known to be true (and often, known in some sense not to be provably true), and therefore are instances of what you requested. The status of these various hypotheses as conjectures, however, to use the word you use, has given rise to vigorous philosophical debate in the foundations of mathematics and set theory, as to whether or not they have definite truth values and how we could come to know them.
Examples of such hypothesis that are used in this way would include all of the main set-theoretic hypotheses known to be independent. This list would run to several hundred natural statements, but let me list just a few:
• The Continuum Hypothesis (also the Generalized Continuum Hypothesis)
• The negation of the Continuum Hypothesis
• Martin's Axiom
• More generally, other forcing axioms, such as PFA or MM
• Cardinal characteristics relations, such as b < d
• The entire large cardinal hierarchy
This last example is extremely important and a unifying instance of what you requested, for the large cardinal hierarchy is a tower of increasingly strong hypotheses, which we believe to be consistent, but haven't proved, and indeed, provably cannot prove, to be consistent, unless set theory itself is inconsistent. From any level of the large cardinal hierarchy, if consistent, we provably cannot prove the consistency of the higher levels.
So in this sense, the large cardinal hierarchy provides enormous iterated towers of your phenomenon.
This might seem at first to be a flaw. Why would we be interested in these large cardinals, if we cannot prove they exist, cannot prove that their existence is consistent, and indeed, can prove that we cannot prove they are consistent, assuming our basic axioms are consistent? The reason is that because of Goedel's incompeteness theorem, we know and expect to find such statements, that are not settled, even when we assume Con(ZFC) and more. Thus, we know there is hierarchy of consistency strength towering above us. The remarkable thing is that this tower turns out to be describable in terms of the very natural infinite combinatorics of large cardinals. These were notions, such as inaccessible, Ramsey and measurable cardinals, that arose from natural questions about infinite combinatorics, independently of any considerations of consistency strength.
Some of the most interesting uses of large cardinals have been equiconsistencies between large cardinals and other natural mathematical statements. For example, the impossibility of removing AC from the Vitali construction of a non-measurable set is exactly equiconsistent with the existence of an inaccessible cardinal. And the complete determinacy of infinite integer games (with not AC) is equiconsistent with the existence of infinitely many Woodin cardinals.
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The standard conjectures (http://en.wikipedia.org/wiki/Standard_conjectures_on_algebraic_cycles) were pretty much designed to be used in this way (and then proved); but proofs are lacking, and some of the results now have non-conditional proofs. There are many related results in the theory of motives.
In number theory, Vandiver's conjecture (http://en.wikipedia.org/wiki/Vandiver%27s_conjecture) has begun to stand out, because of its connection with K-theory (which is another area in which there are large scale conjectures used in this way).
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Wiki also says:
A famous network of conditional proofs is the NP-complete class of complexity theory
-
The ABC conjecture and Vojta's conjectures come to mind.
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Clicking on Toolbox-What Link's Here in the wikipedia article Conditional proof brings up Schinzel's hypothesis H which the article says is used to prove conditional results in diophantine geometry.
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http://mathhelpforum.com/advanced-statistics/51624-3rd-continous-random-variable-question-print.html | # 3rd continous random variable question
• October 1st 2008, 08:23 PM
ban26ana
3rd continous random variable question
Consider the continuous random variable X with probability density function as:
Find
a) the value of C
b) the moment generating function of X
c) the second moment about origin of X
I could do parts b and c, but I don't know how to find C unless it is in the f(x) function.
• October 1st 2008, 08:27 PM
icemanfan
Think of question A this way: what is the value of C that solves the equation $\int _0 ^C 2(1-x) \, dx = 1$?
• October 1st 2008, 08:31 PM
ban26ana
Nevermind, I screwed up a negative. I got C=1. Thank you for your explanation!
• October 1st 2008, 08:35 PM
icemanfan
We have:
$\int _0 ^C 2(1-x) \, dx = 1$
$\int _0 ^C 2 - 2x \, dx = 1$
$2x - x^2 | _0 ^C = 1$
$(2C - C^2) - (2(0) - 0^2) = 1$
$2C - C^2 = 1$
$C^2 - 2C + 1 = 0$
$(C - 1)(C - 1) = 0$
$C = 1$
Good job on getting that before I did.
• October 1st 2008, 08:36 PM
ban26ana
Thanks. I had screwed up a negative in my original calculations. I got it. You made it very easy.
• October 1st 2008, 08:51 PM
ban26ana
Okay, so for the moment generating function, I found the integral to be
Since the denominator is t squared, and we're evaluating from 0 to 1, does this mean that the mgf doesn't exist?
• October 2nd 2008, 12:03 AM
mr fantastic
Quote:
Originally Posted by ban26ana
Okay, so for the moment generating function, I found the integral to be
$m(t) = E\left( e^{tX} \right) = \int_{-\infty}^{+\infty} e^{xt} f(x) \, dx = 2 \int_{0}^{1} e^{xt} (1 - x) \, dx = \frac{2(e^t - t - 1)}{t^2}$.
Confirm that $E(X) = \frac{dm}{dt}$ evaluated at t = 0. | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 11, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.8678028583526611, "perplexity": 1382.4803757688671}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 20, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2015-11/segments/1424936461988.0/warc/CC-MAIN-20150226074101-00306-ip-10-28-5-156.ec2.internal.warc.gz"} |
https://en.wikipedia.org/wiki/Spigot_algorithm | Spigot algorithm
A spigot algorithm is an algorithm for computing the value of a mathematical constant such as π or e which generates output digits in some base (usually 2 or a power of 2) from left to right, with limited intermediate storage. The name comes from the sense of the word "spigot" for a tap or valve controlling the flow of a liquid.
Interest in spigot algorithms was spurred in the early days of computational mathematics by extreme constraints on memory, and such an algorithm for calculating the digits of e appeared in a paper by Sale in 1968.[1] The name "Spigot algorithm" seems to have been coined by Stanley Rabinowitz and Stan Wagon,[2] whose algorithm for calculating the digits of π is sometimes referred to as "the spigot algorithm for π".[citation needed]
The spigot algorithm of Rabinowitz and Wagon is bounded, in the sense that the number of required digits must be specified in advance. Jeremy Gibbons (2004)[3] uses the term "streaming algorithm" to mean one which can be run indefinitely, without a prior bound. A further refinement is an algorithm which can compute a single arbitrary digit, without first computing the preceding digits: an example is the Bailey-Borwein-Plouffe formula, a digit extraction algorithm for π which produces hexadecimal digits.
Example
This example illustrates the working of a spigot algorithm by calculating the binary digits of the natural logarithm of 2 (sequence A068426 in the OEIS) using the identity
${\displaystyle \ln(2)=\sum _{k=1}^{\infty }{\frac {1}{k2^{k}}}\,.}$
To start calculating binary digits from, say, the 8th place we multiply this identity by 27(since 7 = 8 - 1):
${\displaystyle 2^{7}\ln(2)=2^{7}\sum _{k=1}^{\infty }{\frac {1}{k2^{k}}}\,.}$
We then divide the infinite sum into a "head", in which the exponents of 2 are greater than or equal to zero, and a "tail", in which the exponents of 2 are negative:
${\displaystyle 2^{7}\ln(2)=\sum _{k=1}^{7}{\frac {2^{7-k}}{k}}+\sum _{k=8}^{\infty }{\frac {1}{k2^{k-7}}}\,.}$
We are only interested in the fractional part of this value, so we can replace each of the summands in the "head" by
${\displaystyle {\frac {2^{7-k}\mod k}{k}}\,.}$
Calculating each of these terms and adding them to a running total where we again only keep the fractional part, we have:
k A = 27−k B = A mod k C = B / k Sum of C mod 1
1 64 0 0 0
2 32 0 0 0
3 16 1 1/3 1/3
4 8 0 0 1/3
5 4 4 4/5 2/15
6 2 2 1/3 7/15
7 1 1 1/7 64/105
We add a few terms in the "tail", noting that the error introduced by truncating the sum is less than the final term:
k D = 1/k2k-7 Sum of D Maximum error
8 1/16 1/16 1/16
9 1/36 13/144 1/36
10 1/80 37/360 1/80
Adding the "head" and the first few terms of the "tail" together we get:
${\displaystyle 2^{7}\ln(2)\mod {1}\approx {\frac {64}{105}}+{\frac {37}{360}}=0.10011100\cdots _{2}+0.00011010\cdots _{2}=0.1011\cdots _{2}\,,}$
so the 8th to 11th binary digits in the binary expansion of ln(2) are 1, 0, 1, 1. Note that we have not calculated the values of the first seven binary digits – indeed, all information about them has been intentionally discarded by using modular arithmetic in the "head" sum.
The same approach can be used to calculate digits of the binary expansion of ln(2) starting from an arbitrary nth position. The number of terms in the "head" sum increases linearly with n, but the complexity of each term only increases with the logarithm of n if an efficient method of modular exponentiation is used. The precision of calculations and intermediate results and the number of terms taken from the "tail" sum are all independent of n, and only depend on the number of binary digits that are being calculated – single precision arithmetic can be used to calculate around 12 binary digits, regardless of the starting position.
References
1. ^ Sale, AHJ (1968). "The calculation of e to many significant digits". The Computer Journal. 11 (2): 229–230. doi:10.1093/comjnl/11.2.229. Retrieved 8 May 2013.
2. ^ Rabinowitz, Stanley; Wagon, Stan (1995). "A Spigot Algorithm for the Digits of Pi" (PDF). American Mathematical Monthly. 102 (3): 195–203. doi:10.2307/2975006. Retrieved 8 May 2013.
3. ^ Gibbons, Jeremy (24 May 2004). "Unbounded Spigot Algorithms for the Digits of Pi" (PDF). | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 5, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.9027419090270996, "perplexity": 496.56217634936615}, "config": {"markdown_headings": false, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 20, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2018-39/segments/1537267156311.20/warc/CC-MAIN-20180919220117-20180920000117-00440.warc.gz"} |
https://infoscience.epfl.ch/record/179662 | Infoscience
Journal article
# Fermi surface of layered compounds and bulk charge density wave systems
A review is given of recent angle-resolved photoemission (ARPES) experiments and analyses on a series of layered charge density wave materials. Important aspects of ARPES are recalled in view of its capability for bulk band, Fermi surface and spectral function mapping despite its surface sensitivity. Discussed are TaS2, TaSe2, NbTe2, TiSe2 and TiTe2 with structures related to the so-called 1T polytype. Many of them undergo charge density wave transitions or exist with a distorted lattice structure. Attempts to explain the mechanism behind the structural reconstruction are given. Depending on the filling of the lowest occupied band a drastically different behaviour is observed. Whereas density functional calculations of the electronic energy and momentum distribution reproduce well the experimental spectral weight distribution at the Fermi energy, the ARPES energy distribution curves reveal that for some of the compounds the Fermi surface is pseudo-gapped. Two different explanations are given, the first based on density functional calculations accounting for the charge-density-wave-induced lattice distortion and the second relying on many-body physics and polaron formation. Qualitatively, both describe the observations well. However, in the future, in order to be selective, quantitative modelling will be necessary, including the photoemission matrix elements. | {"extraction_info": {"found_math": false, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.9457330703735352, "perplexity": 1784.2364187911605}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2017-09/segments/1487501170614.88/warc/CC-MAIN-20170219104610-00376-ip-10-171-10-108.ec2.internal.warc.gz"} |
https://www.msri.org/workshops/953/schedules/30578 | # Mathematical Sciences Research Institute
Home » Workshop » Schedules » Lozenge Tilings and the Gaussian Free Field on a Cylinder
# Lozenge Tilings and the Gaussian Free Field on a Cylinder
## [HYBRID WORKSHOP] Integrable Structures in Random Matrix Theory and Beyond October 18, 2021 - October 22, 2021
October 20, 2021 (11:30 AM PDT - 12:20 PM PDT)
Speaker(s): Marianna Russkikh (Massachusetts Institute of Technology)
Location: MSRI: Simons Auditorium, Online/Virtual
Tags/Keywords
• lozenge tilings
• periodic Schur process
• Gaussian free field
Primary Mathematics Subject Classification
Secondary Mathematics Subject Classification No Secondary AMS MSC
Video
#### Lozenge Tilings And The Gaussian Free Field On A Cylinder
Abstract
We discuss new results on lozenge tilings on an infinite cylinder, which may be analyzed using the periodic Schur process introduced by Borodin. Under one variant of the $q^{vol}$ measure, corresponding to random cylindric partitions, the height function converges to a deterministic limit shape and fluctuations around it are given by the Gaussian free field in the conformal structure predicted by the Kenyon-Okounkov conjecture. Under another variant, corresponding to an unrestricted tiling model on the cylinder, the fluctuations are given by the same Gaussian free field with an additional discrete Gaussian shift component. Fluctuations of the latter type have been previously conjectured for tiling models on planar domains with holes.
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#### Lozenge Tilings And The Gaussian Free Field On A Cylinder
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Please report video problems to itsupport@msri.org.
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https://arxiv.org/abs/1311.6519 | astro-ph.HE
(what is this?)
# Title: Recent Highlights from IceCube
Abstract: The $\sim$1 km$^3$ IceCube neutrino observatory was completed in December, 2010 and is taking data on cosmic-ray muons and neutrinos, extra-terrestrial neutrinos, and setting limits on a variety of exotic phenomena. This proceeding will cover recent IceCube results, with an emphasis on cosmic-rays and on searches for extra-terrestrial neutrinos, with a stress on results that were presented at the 2013 International Cosmic Ray Conference.
Comments: 9 pages; plenary highlight talk presented at the 2013 Intl.Cosmic Ray Conf. The full collaboration author list is available at this http URL Subjects: High Energy Astrophysical Phenomena (astro-ph.HE); High Energy Physics - Experiment (hep-ex) Cite as: arXiv:1311.6519 [astro-ph.HE] (or arXiv:1311.6519v1 [astro-ph.HE] for this version)
## Submission history
From: Spencer Klein [view email]
[v1] Tue, 26 Nov 2013 00:02:25 GMT (6209kb) | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.3790762424468994, "perplexity": 11959.695376098502}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2017-26/segments/1498128320685.63/warc/CC-MAIN-20170626064746-20170626084746-00689.warc.gz"} |
https://en.m.wikipedia.org/wiki/Kardashev_scale | # Kardashev scale
The Kardashev scale is a method of measuring a civilization's level of technological advancement based on the amount of energy it is able to use. The measure was proposed by Soviet astronomer Nikolai Kardashev in 1964.[1]
Energy consumption estimated in three types of civilizations defined by Kardashev scale
## Categories
The Kardashev scale has three designated categories, these are:
• A Type I civilization, also called a planetary civilization, can use and store all of the energy available on its planet.
• A Type II civilization, also called a stellar civilization, can use and control energy at the scale of its planetary system.
• A Type III civilization, also called a galactic civilization, can control energy at the scale of its entire host galaxy.
## Definition
In 1964, Kardashev defined three levels of civilization, based on the order of magnitude of power available to each:
Type I
Technological level of a civilization that is "close to the level presently attained on Earth, with energy consumption at ≈4×1019 erg/sec" (4×1012 watts).[2] Currently, the civilization of Type I is usually defined as one that can harness all the energy that falls on a planet from its parent star (for Earth–Sun system, this value is close to 1.74×1017 watts), which is about four orders of magnitude higher than the amount presently attained on Earth, with energy consumption at ≈2×1013 watts. The astronomer Guillermo A. Lemarchand stated this as a level near contemporary terrestrial civilization with an energy capability equivalent to the solar insolation on Earth, between 1016 and 1017 watts.[3]
Type II
A civilization capable of harnessing the energy radiated by its own star—for example, the stage of successful construction of a Dyson sphere or Matrioshka brain—with energy consumption at ≈4×1033 erg/sec.[2] Lemarchand stated this as a civilization capable of using and channeling the entire radiation output of its star. The energy use would then be comparable to the luminosity of the Sun, about 4×1033 erg/sec (4×1026 watts).[3]
Type III
A civilization in possession of energy at the scale of its own galaxy, with energy consumption at ≈4×1044 erg/sec.[2] Lemarchand stated this as a civilization with access to the power comparable to the luminosity of the entire Milky Way galaxy, about 4×1044 erg/sec (4×1037 watts).[3]
Kardashev believed that a Type 4 civilization was impossible, so he did not go past Type 3. However, new types (0, IV, V, VI) have been proposed.[citation needed]
## Current status of human civilization
Total World, Annual Primary Energy Consumption.
According to the astronomer Carl Sagan, humanity is currently going through a phase of technical adolescence, "typical of a civilization about to integrate the type I Kardashev scale."
At the current time, humanity has not yet reached Type I civilization status. Physicist and futurist Michio Kaku suggested that, if humans increase their energy consumption at an average rate of 3 percent each year, they may attain Type I status in 100–200 years, Type II status in a few thousand years, and Type III status in 100,000 to a million years.[4]
Carl Sagan suggested defining intermediate values (not considered in Kardashev's original scale) by interpolating and extrapolating the values given above for types I (1016 W), II (1026 W) and III (1036 W), which would produce the formula
${\displaystyle K={\frac {\log _{10}P-6}{10}}}$ ,
where value K is a civilization's Kardashev rating and P is the power it uses, in watts. Using this extrapolation, a "Type 0" civilization, not defined by Kardashev, would control about 1 MW of power, and humanity's civilization type as of 1973 was about 0.7 (apparently using 10 terawatt (TW) as the value for 1970s humanity).[5]
In 2019, the total world energy consumption was 14864.9 Mtoe (175,249 TWh),[6] equivalent to an average power consumption of 20.0 TW or 0.73 on Sagan's interpolated Kardashev scale.
## Observational evidence
In 2015, a study of galactic mid-infrared emissions came to the conclusion that "Kardashev Type-III civilizations are either very rare or do not exist in the local Universe".[7]
In 2016, Paul Gilster, author of the Centauri Dreams website, described a signal apparently from the star HD 164595 as requiring the power of a Type I or Type II civilization, if produced by extraterrestrial lifeforms.[8] However, in August 2016 it was discovered that the signal's origin was most likely a military satellite orbiting the Earth.[9]
## Energy development
### Type I civilization methods
• Large-scale application of fusion power. According to mass–energy equivalence, Type I implies the conversion of about 2 kg of matter to energy per second. An equivalent energy release could theoretically be achieved by fusing approximately 280 kg of hydrogen into helium per second,[10] a rate roughly equivalent to 8.9×109 kg/year. A cubic km of water contains about 1011 kg of hydrogen, and the Earth's oceans contain about 1.3×109 cubic km of water, meaning that humans on Earth could sustain this rate of consumption over geological time-scales, in terms of available hydrogen.
• Antimatter in large quantities would provide a mechanism to produce power on a scale several magnitudes above the current level of technology.[citation needed] In antimatter-matter collisions, the entire rest mass of the particles is converted to radiant energy. Their energy density (energy released per mass) is about four orders of magnitude greater than that from using nuclear fission, and about two orders of magnitude greater than the best possible yield from fusion.[11] The reaction of 1 kg of anti-matter with 1 kg of matter would produce 1.8×1017 J (180 petajoules) of energy.[12] Although antimatter is sometimes proposed as a source of energy, this does not appear feasible. Artificially producing antimatter—according to current understanding of the laws of physics—involves first converting energy into mass, which yields no net energy. Artificially created antimatter is only usable as a medium of energy storage, not as an energy source, unless future technological developments (contrary to the conservation of the baryon number, such as a CP violation in favor of antimatter) allow the conversion of ordinary matter into anti-matter. Theoretically, humans may in the future have the capability to cultivate and harvest a number of naturally occurring sources of antimatter.[13][14][15]
• Renewable energy through converting sunlight into electricity—either by using solar cells and concentrating solar power or indirectly through biofuel, wind and hydroelectric power. There is no known way for human civilization to use the equivalent of the Earth's total absorbed solar energy without completely coating the surface with human-made structures, which is not feasible with current technology. However, if a civilization constructed very large space-based solar power satellites, Type I power levels might become achievable—these could convert sunlight to microwave power and beam that to collectors on Earth.
Figure of a Dyson swarm surrounding a star
### Type II civilization methods
• Type II civilizations might use the same techniques employed by a Type I civilization, but applied to a large number of planets in a large number of planetary systems.
• A Dyson sphere or Dyson swarm and similar constructs are hypothetical megastructures originally described by Freeman Dyson as a system of orbiting solar power satellites meant to enclose a star completely and capture most or all of its energy output.[16]
• Another means to generate usable energy would be to feed a stellar mass into a black hole, and collect photons emitted by the accretion disc.[17][18] Less exotic would be simply to capture photons already escaping from the accretion disc, reducing a black hole's angular momentum; this is known as the Penrose process. This, however, may only be possible for a Type III civilization to achieve.
• Star lifting is a process where an advanced civilization could remove a substantial portion of a star's matter in a controlled manner for other uses.
• Antimatter is likely to be produced as an industrial byproduct of a number of megascale engineering processes (such as the aforementioned star lifting) and, therefore, could be recycled.[citation needed]
• In multiple-star systems of a sufficiently large number of stars, absorbing a small but significant fraction of the output of each individual star.
### Type III civilization methods
• Type III civilizations might use the same techniques employed by a Type II civilization, but applied to all possible stars of one or more galaxies individually.[19]
• They may also be able to tap into the energy released from the supermassive black holes believed to exist at the center of most galaxies.
• White holes could theoretically provide large amounts of energy from collecting the matter propelling outwards.
• Capturing the energy of gamma-ray bursts is another theoretically possible power source for a highly advanced civilization.
• The emissions from quasars are comparable to small active galaxies and could provide a massive power source if collectible.
## Civilization implications
There are many historical examples of human civilization undergoing large-scale transitions, such as the Industrial Revolution. The transition between Kardashev scale levels could potentially represent similarly dramatic periods of social upheaval since they entail surpassing the hard limits of the resources available in a civilization's existing territory. A common speculation[20] suggests that the transition from Type 0 to Type I might carry a strong risk of self-destruction since, in some scenarios, there would no longer be room for further expansion on the civilization's home planet, as in a Malthusian catastrophe. Excessive use of energy without adequate heat disposal, for example, could plausibly make the planet of a civilization approaching Type I unsuitable to the biology of the dominant life-forms and their food sources. If Earth is an example, then sea temperatures in excess of 35 °C (95 °F) would jeopardize marine life and make the cooling of mammals to temperatures suitable for their metabolism difficult if not impossible. Of course, these theoretical speculations may not become problems, possibly through the applications of future engineering and technology. Also, by the time a civilization reaches Type I it may have colonized other planets or created O'Neill-type colonies, so that waste heat could be distributed throughout the planetary system.
The limitation of biological life-forms and the evolution of computing technology may lead to the transformation of the civilization through mind uploading and artificial general intelligence in general during the transition from Type I to Type II, leading to a digitalized civilization.
## Extensions to the original scale
Many extensions and modifications to the Kardashev scale have been proposed.
• Types 0, IV, and V Kardashev rating: The most straightforward extension of the scale to even more hypothetical Type IV beings who can control or use the entire universe or Type V who control collections of universes. This would also include Type 0 civilizations, who do not rank on the Kardashev scale. The power output of the visible universe is within a few orders of magnitude of 1045 W. Such a civilization approaches or surpasses the limits of speculation based on current scientific understanding and may not be possible.
• Zoltán Galántai has argued that such a civilization could not be detected, as its activities would be indistinguishable from the workings of nature (there being nothing to compare them to).[21]
• In his books Hyperspace and Parallel Worlds, Michio Kaku has discussed a Type IV civilization that could harness "extragalactic" energy sources such as dark energy.[22]
### Kardashev alternative rating characteristics
Other proposed changes to the scale use different metrics such as 'mastery' of systems, amount of information used, or progress in control of the very small as opposed to the very large:
• Planet mastery (Robert Zubrin): Metrics other than pure power usage have also been proposed. One is 'mastery' of a planet, system or galaxy rather than considering energy alone.[23]
• Information mastery (Carl Sagan): Alternatively, Carl Sagan suggested adding another dimension in addition to pure energy usage: the information available to the civilization.
• He assigned the letter A to represent 106 unique bits of information (less than any recorded human culture) and each successive letter to represent an order of magnitude increase so that a level Z civilization would have 1031 bits.
• In this classification, 1973 Earth is a 0.7 H civilization, with access to 1013 bits of information, in 2018, Earth was a 0.73 J civilization.
• Sagan believed that no civilization has yet reached level Z, conjecturing that so much unique information would exceed that of all the intelligent species in a galactic supercluster and observing that the universe is not old enough to exchange information effectively over larger distances.
• The information and energy axes are not strictly interdependent so that even a level Z civilization would not need to be Kardashev Type III.[5]
• Microdimensional mastery (John Barrow): John D. Barrow observed that humans have found it more cost-effective to extend their abilities to manipulate their environment over increasingly small scales rather than increasingly large ones. He, therefore, proposes a reverse classification downward from Type I-minus to Type Omega-minus:
• Type I-minus is capable of manipulating objects over the scale of themselves: building structures, mining, joining and breaking solids;
• Type II-minus is capable of manipulating genes and altering the development of living things, transplanting or replacing parts of themselves, reading and engineering their genetic code;
• Type III-minus is capable of manipulating molecules and molecular bonds, creating new materials;
• Type IV-minus is capable of manipulating individual atoms, creating nanotechnologies on the atomic scale, and creating complex forms of artificial life;
• Type V-minus is capable of manipulating the atomic nucleus and engineering the nucleons that compose it;
• Type VI-minus is capable of manipulating the most elementary particles of matter (quarks and leptons) to create organized complexity among populations of elementary particles; culminating in:
• Type Omega-minus is capable of manipulating the basic structure of space and time.[24]
The human civilization is somewhere between type III-minus and types IV-minus according to this classification.
• Civilizational range (Robert Zubrin): Robert Zubrin adapts the Kardashev scale to refer to how widespread a civilization is in space, rather than to its energy use.
• In his definition, a Type I civilization has spread across its planet.
• A Type II has extensive colonies in its respective stellar system, and
• A Type III has colonized its galaxy.[23]
## References
2. ^ a b c Kardashev, Nikolai (1964). "Transmission of Information by Extraterrestrial Civilizations". Soviet Astronomy. 8: 217–221. Bibcode:1964SvA.....8..217K.
3. ^ a b c Lemarchand, Guillermo A. "Detectability of Extraterrestrial Technological Activities". Coseti. Archived from the original on 2019-03-18. Retrieved 2004-10-23.
4. ^ Kaku, Michio (2010). "The Physics of Interstellar Travel: To one day, reach the stars". Archived from the original on 2014-02-10. Retrieved 2010-08-29.
5. ^ a b Sagan, Carl (October 2000) [1973]. Jerome Agel (ed.). Cosmic Connection: An Extraterrestrial Perspective. Freeman J. Dyson, David Morrison. Cambridge Press. ISBN 978-0-521-78303-3. Retrieved 2008-01-01. I would suggest Type 1.0 as a civilization using 1016 watts for interstellar communication; Type 1.1, 1017 watts; Type 1.2, 1018 watts, and so on. Our present civilization would be classed as something like Type 0.7.
6. ^ "BP Statistical Review of World Energy 2019" (PDF). bp.com. BP plc. Archived (PDF) from the original on 17 October 2020. Retrieved 22 December 2019.
7. ^ Garrett, Michael (2015). "The application of the Mid-IR radio correlation to the Ĝ sample and the search for advanced extraterrestrial civilizations". Astronomy & Astrophysics. 581: L5. arXiv:1508.02624. Bibcode:2015A&A...581L...5G. doi:10.1051/0004-6361/201526687. S2CID 67817641.
8. ^ Gilster, Paul (August 27, 2016). "An Interesting SETI Candidate in Hercules". Centauri Dreams. Archived from the original on 2018-01-10. Retrieved 2016-08-29.
9. ^ "Alien signal detected by Russian astrophysicists turns out to be terrestrial disturbance". tass.com. St. Petersburg, Russia: TASS. 2016-08-30. Archived from the original on 2016-09-03. Retrieved 2016-09-02.
10. ^ Souers, P. C. (1986). Hydrogen properties for fusion energy. University of California Press. p. 4. ISBN 978-0-520-05500-1. Archived from the original on 2020-07-08. Retrieved 2020-06-06.
11. ^ Borowski, Steve K. (1987-07-29). "Comparison of Fusion/Anti-matter Propulsion Systems for Interplanetary Travel" (PDF). Technical Memorandum 107030. San Diego, California, USA: National Aeronautics and Space Administration. pp. 1–3. Archived from the original (PDF) on 2008-05-28. Retrieved 2008-01-28.
12. ^ By the mass–energy equivalence formula E = mc². See antimatter as a fuel source for the energy comparisons.
13. ^ Than, Ker (August 10, 2011). "Antimatter Found Orbiting Earth—A First". National Geographic News. Archived from the original on October 10, 2011. Retrieved August 25, 2011.
14. ^ Adriani; Barbarino; Bazilevskaya; Bellotti; Boezio; Bogomolov; Bongi; Bonvicini; Borisov (2011). "The discovery of geomagnetically trapped cosmic ray antiprotons". The Astrophysical Journal. 736 (29): L1. arXiv:1107.4882. Bibcode:2011ApJ...736L...1H. doi:10.1088/2041-8205/736/1/L1.
15. ^ Palmer, Jason (2011-01-11). "Antimatter caught streaming from thunderstorms on Earth". BBC News. Archived from the original on 2011-01-12. Retrieved 2015-12-29.
16. ^ Dyson, Freeman J. (1966). Marshak, R. E. (ed.). "The Search for Extraterrestrial Technology". Perspectives in Modern Physics. New York: John Wiley & Sons. Bibcode:1966pmp..book..641D.
17. ^ Newman, Phil (2001-10-22). "New Energy Source "Wrings" Power from Black Hole Spin". NASA. Archived from the original on 2008-02-09. Retrieved 2008-02-19.
18. ^ Schutz, Bernard F. (1985). A First Course in General Relativity. New York: Cambridge University Press. pp. 304, 305. ISBN 978-0-521-27703-7. Archived from the original on 2020-07-10. Retrieved 2019-07-29.
19. ^ Kardashev, Nikolai. "On the Inevitability and the Possible Structures of Supercivilizations Archived 2017-10-28 at the Wayback Machine", The search for extraterrestrial life: Recent developments; Proceedings of the Symposium, Boston, MA, June 18–21, 1984 (A86-38126 17-88). Dordrecht, D. Reidel Publishing Co., 1985, p. 497–504. Bibcode 1985IAUS..112..497K .
20. ^ Dyson, Freeman (1960-06-03). "Search for Artificial Stellar Sources of Infrared Radiation". Science. 131 (3414): 1667–1668. Bibcode:1960Sci...131.1667D. doi:10.1126/science.131.3414.1667. PMID 17780673. S2CID 3195432. Archived from the original on 2019-07-14. Retrieved 2008-01-30.
21. ^ Galántai, Zoltán (September 7, 2003). "Long Futures and Type IV Civilizations" (PDF). Archived (PDF) from the original on 2013-10-05. Retrieved 2014-11-03.
22. ^ Kaku, Michio (2005). Parallel Worlds: The Science of Alternative Universes and Our Future in the Cosmos. New York: Doubleday. p. 317. ISBN 978-0-7139-9728-6.
23. ^ a b Zubrin, Robert (1999). Entering Space: Creating a Spacefaring Civilization. ISBN 978-1585420360.
24. ^ Barrow, John (1998). Impossibility: Limits of Science and the Science of Limits. Oxford: Oxford University Press. p. 133. ISBN 978-0198518907. | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 1, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.7961545586585999, "perplexity": 3045.653731477868}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2021-49/segments/1637964358702.43/warc/CC-MAIN-20211129074202-20211129104202-00579.warc.gz"} |
https://www.businessballs.com/amusement-stress-relief/games-tricks-puzzles-and-warm-ups-for-groups/ | # Games, tricks, puzzles and warm ups for groups
Free trivia questions, lateral thinking puzzles and exercises - free answers too!
### puzzles, games, trivia questions and answers for quizzes, team building activities, training and motivation
#### free trivia questions, lateral thinking puzzles and exercises - free answers too!
On this page are lots of clever riddles, puzzles, lateral thinking puzzles, trick questions, number puzzles, logic puzzles and word games, all which can be used for team building exercises or party games.
Games, tricks and puzzles help team building, motivation, and warm up any gathering.
These free questions, games and puzzles are useful for ice breakers for training sessions, meetings, workshops, seminars or conferences.
Some of these puzzles are too tricky or time-consuming for quick quizzes.
If you want quick questions and answers for quizzes - or stand-alone ready-made quizzes - you'll find hundreds of quiz questions and answers at the Quizballs section.
You can also find content for quizzes and team games on the ditloids puzzles page, the tough complex puzzles, and try the expressions derivations quiz.
The team building games section gives advice on running games and exercises, and connects with the two big collections of team building and employee motivation ideas.
Giving groups or teams a mixed set of puzzles gets people working together and using each other's strengths. These puzzles are great for games and competitive team building exercises. Many of the puzzles can be adapted, enlarged or shortened, or made easier by turning into multiple-choice. Have fun, and try not to use them all at once tricky questions and puzzles need to be used sparingly, as dictinct from quizzes, which mainly test of people's knowledge, rather than their puzzle-solving capabilities.
If you need a warm-up quiz quickly, here's a free ready-made Quick Ten-Question Trivia Quiz in MSWord, with questions and answers sheets featuring questions from the list below.
See also the amazing mobius strip puzzle below, which is good creating a stimulating warm-up exercise.
Quizzes and trivia questions are fun and helpful for learning, for teambuilding, and quizzes are also good for your brain and your mental fitness. Research now proves that people who keep learning and keep their brains exercised tend to stay mentally fit and healthy longer than people who do not exercise their minds.
Or share your puzzles and exerecises on the free self-publishing Businessballs Space.
### businessballs puzzles and questions
#### for quizzes and team building games - puzzles answers here
Please note - the puzzles on this page are not really suitable for pub quizzes or quick quizzes for teams, because they take longer to work out than typical quiz questions.
If you are looking for ready-made quizzes which test knowledge rather than problem solving see the many quizzes on the Quizballs quizzes section, where each quiz has its own separate questions and answers pages.
What's special about 4th May 2006, and specifically two minutes and three seconds after one o'clock in the morning? (puzzles answers here)
What are the astrological star signs and the two months that each sign represents? (The symbols and precise dates are optional details and not necessarily required in quiz answers.)
Who wrote: "Bring me my bow of burning gold: Bring me my arrows of desire.." ?
What famous slogan was originally devised by Patrick O'Keefe for the Society of American Florists?
What connects the words sitcom, smog, brunch, muppet and cyborg?
What symbolic item did Lauren Bacall put into the urn containing Humphrey Bogart's ashes?
Which one of these is on the coast: Cairo, Johannesburg, Tripoli, Sarajevo, Nairobi, Khartoum?
Which of these is not on the coast: Venice, San Diego, Reykjavik, Marrakesh, Helsinki, Lisbon?
What upper case (capital) letter of the English alphabet (in plain sans serif font) requires that the pen be lifted from the paper twice (providing no lines are re-traced)? (Sans serif is like Arial; serif font is like Times - serif font has the extra decorative strokes at the ends of the main strokes - said to derive from engravers' practice, and actually useful in providing a horizontal reading flow for printed words.)
A famous leader's first name of Mohandas is commonly replaced by a first name that means 'great soul'; who was he?
Who was the 'The Wizard of Menlo Park' who said, "Genius is one percent inspiration, ninety-nine percent perspiration." ?
Paul McGann, Peter Davidson and William Hartnell have each played the same famous sci-fi role. What's the character's name?
What is the largest English town or city never (as of 2005/06) to have been represented in the top English football division (the old First Division and now the Premier League)? Supplementary question: What is also unique about this full club name in the entire professional football league system?
There are four (known to us - perhaps there are more) perfectly recognisable and understandable words in the English language having one of each vowel in reverse alphabetical order (UOIEA), what are the words?
Why would the following stand no chance of being approved as official names for British racehorses? - Salisbury Cathedral, Wonderful Terminator, Sexy Disciplinarian or Sea Bee.
How much time elapses between any Sunday 29 February and (going forward in time) the next respective Tuesday 29 February? (This is not a trick question and is reasonably straight-forward to work out if you have that sort of brain...) A supplementary question is: what year was the last Sunday 29 February? (Again this is straight-forward to work out if you know the current day and date, and have the right sort of brain....)
This is a very impressive trick; especially because the solution is for real; it's not a trick.
#### the paintings puzzle
This is an excellent lateral-thinking and maths puzzle:
An art gallery features a modern work of 'moving art'. The artist stands by a stack of paintings, each featuring a different number. One of the paintings is displayed on the wall. At certain times the artist removes the painting from the wall and replaces it with a painting from the stack. At 11am, the artist hangs a painting of the number 30. At 4pm he hangs a painting of number 240. At 7.30pm he hangs a painting of number 315. What painting does the artist hang at 9.20pm? Answer
#### the spotlight puzzle
A conference room contains three separate wall-mounted spotlights - right, left and front of stage. Each is controlled by its own on-off switch. These three switches are numbered 1, 2 and 3, but they are in a back-room which has no sight of the the spotlights or the conference room (and there are no reflections or shadows or mirrors, and you are alone). How do you identify each switch correctly - right, left, front - if you can only enter the back-room once? Answer
What famous UK business institution has the postal code CF14 3UZ? (puzzles answers here)
Months of the year that begin on a Sunday (other than February in non-leap-years) always have five Sundays. What other notable feature do they (including all Februarys) contain?
What connects these words?... Dram, Colon, Won, Dong, Kip.
Hedy Lamarr achieved what notable cinematic 'first' in 1933? (If you can state any of her other interesting claims to fame, then award yourself a bonus point for each...)
With what papers do you associate Sam Weller?
What do these Shakespeare plays have in common?... Julius Caesar, Richard III, Hamlet, Macbeth.
Where was Britain's first escalator installed?
'Dieu Et Mon Droit' appears on which daily header?
What do these items have in common?... Arrow, Ladder, Spanner, Hockey-Stick, T-Square, Crutch.
The drummer with little known 1960's high school rock group the Iguanas became which music and style icon?
Christopher Leyland's discovery on his brother-in-law's estate near Powys, Wales in 1888, was what?
Scientist Dr Alexander Graham Bell, inventor of the telephone, had what well known unit of measurement was named after him?
What is the connection between Ben Corson and Roger Stoughton and riot control?
What was Pall Mall before it was a famous London street and a brand of cigarettes?
The bacillus-based invention of French bacteriologists Albert Calmette and Camille Guérin, and the reason for their invention gave rise to two well-known abbreviations, what are they?
A maritime poser: Homo-Sapien ÷ Rent = ?
What do these words have in common, and what does each mean in that common context? - string, ostentation, smack, pitying, crash, unkindness, murmuration, drove, pod, murder, knot, colony, grist, brood, shrewdness, school, siege.
What 15-letter word contains the letter 'E' five times and no other vowels?
To circus people, what is a 'First of May Joey'?
What is deoxyribonucleic acid?
What is the only US state which borders with just one other US state?
JCB is the name of the famous earth-moving machines; what does JCB stand for?
What word ends with an S in its plural masculine form, but changes to singular feminine when another S is added to the end? There are now two examples of this known to me. (Ack D Robinson and M Trollope) answer
Many flags of European countries have three stripes, vertical or horizontal - how many of the following do you know?
(vertical stripes left to right - technically first colour is the one at the 'hoist', i.e., nearest the flagpole)
black/yellow/red -
blue/white/red -
green/white/red -
green/white/orange -
(horizontal stripes top to bottom)
red/white/green -
black/red/yellow -
white/green/red -
red/yellow/red -
yellow/green/red -
blue/black/white -
red/white/blue -
What is the capacity of a 'barrel' as commonly referenced for crude oil production? Also, what does OPEC stand for, and what are the eleven member countries (as at October 2004)?
Whose dogs? -
• Albie
• Argos
• Bagel
• Bimbo
• Blondi
• Boatswain
• Checkers, Vicky and King Timahoe
• Gnasher
• Gromit
• Kasbec
• Krypto
• Mafia
• Muttley
• Nana
• Nipper
• Peritas
• Precious Pup
• Rambler
• Snert
• Snoopy
• Snowy
• Susan, Emma, Linnet, Holly and Willow
• Turk
What cities are most commonly known by these nicknames? (There is more than one answer for some):-
• City of Dreaming Spires
• City of Magnificent Distances
• City of the Angels
• City of Churches
• City of Love
• City of Peace and Justice
• City of the Tribes/the Eternal City
• City of the Violated Treaty/Stab City
• City of the Violet Crown
• Crescent City
• Empire City
• The Fair City
• Forbidden City
• Granite City
• The Harbour City/Emerald City
• Monumental City/Charm City
• Mormon City
• Orchid City
• Quaker City
• Soul City
• The Stampede City
• Windy City
• Motor City
• Music City
• The Steel City
• The White City of the North
Where would you find stags and kites (along with a couple of other creatures that would surely give the game away)?
What was 'Sphairistike'? (The word is Greek, loosely meaning 'ball-game', and an earlier version was known by the French as 'Jeu de Paume').
What icon of 20th century design was the Chapman Root Glass Company of Indiana responsible for introducing in 1915?
Who were the famous riders of these horses? - Bucephalos, Black Bess, Arion, Copenhagen, Marengo, Babieca, Dapple (an ass), Incitatus, Pegasus (three possible answers), Trigger, White Surrey, Midnight.
What twelve animals feature in Chinese astrology?
These seemingly unpronouncable sounds actually appear in common English words; what are the three words? - sthm, tchphr, tchst. (There is also a less common additional word featuring the 'sthm' letter set - ack JP.)
These very old iconic symbols were responsible for what modern system? - the moon, the sun, the planet Saturn, and the Anglo-Saxon gods: Thor, Tiw, Woden, and his wife Frig.
Cryptic anagram puzzles (the clues are in the questions):
• dirty room
• here come dots
• lost cash in, me
• alas, no more z's
• I'm a dot in place
• eleven plus two
A father took his son to hospital for emergency treatment after an accident. The doctor greeted them, but on seeing the boy, exclaimed, "I can't operate on him - he's my son!" How can this be? (The son was not adopted, nor a step-son.)
The 'Frying Pan' was a 1931 prototype and early production nickname for what item of electro-magnetic equipment?
Hartnell and Troughton did it on TV. Who did it in a movie film in the same decade?
What do these British people have in common? J S Lowry, David Bowie, French and Saunders, Nigella Lawson, Vanessa Redgrave, Albert Finney, Jon Snow, John le Carre, Aldous Huxley, Roald Dahl, Evelyn Waugh and George Melly.
Lincoln's stunning 1955 Futura convertible concept car appeared in motor shows to wide acclaim until 1959, when it achieved greater notoriety, featuring the 1959 film 'It Started With A Kiss' starring Glenn Ford and Debbie Reynolds. The car later became even more famous for what reason?
Name a common word with five consecutive vowels.
What morbid coincidence occured at 12 Curzon Place, Mayfair, London?
Catholic bishops are allowed seven of them, priests five, and ordinary people one; what are they?
Why do we say 'Bless you' to someone who has sneezed?
Whose secret ingredient is code-named 7X?
Why did so many sailors have a crucifix tattooed on their backs in the 1700's?
What unique feature do the words PRECEPTOR and DILLYDALLY have in common?
What's the longest word in the English language with only one vowel (which appears once only in the word)?
What do the words ALMOST and BIOPSY have in common?
What's the only word in the English language having four consecutive double letters? (See also the Hoover Dam Word Puzzle)
Draw a capital T over a capital C so that the down-stroke of the T ends in the centre of the C. What historial event does this represent?
What five odd figures when added together make fourteen?
The time displayed usually on watches and clocks in adverts is what?, and why?
What are the only four commonly used words in the English language ending in 'dous'? (There is a fourth not-so-common word, and a fifth very uncommon word, which also has one of each vowel in the correct order.)
What is the only word in the English language that ends in 'mt'?
What are the longest one-syllable words in the English language? (You're looking for a ten-letter word, and/or several nine-letter words. To turn this into a virtually impossible question, find a nine-letter word that doesn't begin with 'S' - we are aware of only two such examples)
Think of a words that sound exactly the same and have opposite meanings. (They are spelt differently but phonetically - they sound - the same.) We know of four such words pairs, each which has two different spellings, same sound, and opposite meanings.
Now think of a words pairings which are spelt the same and have two opposite meanings. There are several examples of such word pairs, plus another two pairs or hyphenated double-word constructions, again with same spellings and opposite meanings. A word having two opposite meanings and same spelling is called a contranym or antagonym.
And extending the theme, what words in the English language occur in two forms, exactly the same spelling, with opposite meanings? (We know eight of these words.)
What trades or occupations are associated with these surnames? (easy ones first) Turner, Joiner, Glazier, Draper, Wakeman, Cartwright, Bowyer, Fletcher, Wainwright, Tanner, Scrivener, Sexton, Cooper, Horner, Chandler, Mercer, Hayward, Franklin, Fuller/Tucker/Walker (all same), Hine, Bicker.
The sequence 1, 2, 3, 4, 5, 6, 7, 8, 9, 10 incorporates another sequence: 1, 1, 1, 2, 2, 1, 1, 1, 1, 2. Why?
What connects Wedgwood pottery and The Origin Of Species?
What do these three-letter groups have in common? ABZ, BGO, HAJ, MEL, ORD, SPK.
How did the TVR sports car firm get its name?
What is 'trichlorophenylmethyliodisalicyl' more commonly known as?
Name the Wacky Races cars and drivers.
What order is denoted by the following prefixes? First, Middle, Morning, Forenoon, Afternoon, First Dog, Last Dog.
Complete the sequence: (three more needed): S, H, S, M, C, D, P, R, O, ...
In 1860 Frederick Walton named his new product after the latin words for its two main constituents, flax and oil. What was it?
Why was Dr Who's 'Tardis' so called?
Shepherd and Turpin invented something that derived its name from theirs, and the name of the factory where it was first produced in 1941. What was it?
BUNCH was an acronym at one time representing the big names in the computer industry competing with the dominant market leader IBM, can you name them?
What was the origin of the 3M company name?
Reinhard Goerdeler, Piet Klyjnveld, James Marwick, and William Barclay Peat founded businesses which merged to become what famous four-letter acronymic global corporation?
What did Mikoyan and Gurevich design?
What's the difference between a rhombus and a rhomboid?
The first Englishman to be killed in a plane crash had another claim to fame, what was it?
What's noteworthy about the words 'reverberated' and 'stewardesses' in relation to typing? And in the same vein, Lollipop?
Name a fifteen letter word containing fifteeen different letters.
Complete the sequence (five more required): deca, hecto, kilo,...
What do these pairings have in common and what is the odd pair in the sequence? - AA, AI, IO, OU, OX, BO, KI.
What is it? - the people who make it don't want it, the people who buy it don't use it and the people who use it don't know.
What do these items have in common? - Vivien Leigh's 1939 Oscar for her performance in Gone With The Wind; Marylin Monroe's dress that she wore when she sang Happy Birthday to President John Kennedy at Madison Square Gardens in 1962; Leonardo da Vinci's 16th century Codex Hammer notebook.
What is assessed by the international grading system known as the Four C's, and what does each of the C's represent?
What's special about these sets of letters: SA - DK - XLNC - NV - NME - FND - XPDNC?
To ensure a fair division between two people (for dividing chocolate bars between children for instance) you might use the 'one cuts, the other chooses' method. How do you ensure a fair division between three people? (Thanks David Grech)
Who were 'Too Much' and Norville Rogers?
There are lots of countries and continents that begin with the letter 'A'. Two of them differ from the rest; which two and why? (Thanks Rupert Stubbs)
Who has appeared more often than any other woman on the cover of Time magazine?
What do these pairs have in common? Lenny Henry and Michael Jackson - Peter Gabriel and Stevie Wonder - John Motson and Virginia Wade - Stanley Kubrick and Danny La Rue - Charles Dance and Chris Tarrant.
What oversized onomatopoeically named mechanism was put on display for people to use at the British Wembley Exhibition is 1924, in order to reassure the public as to its safety and reliability?
A pair of red shoes were sold at auction in 1988 for £90,000. What made them special?
What is unusual and probably unique about British postage stamps?
A man is walking home with his dog at a steady 4mph. With 6 miles to go the dog is let off the leash and runs all the way home at 6 mph. The dog immediately turns and runs back to the man at the same speed, and upon meeting him it turns and runs home again. It continues to run back and forth at the same speed until the man reaches home. What distance has the dog run since being let off the leash?
What word (in the English language) has six vowels, and every one is 'A'?
Each of these famous people is related (not by marriage) to one other person in the list. How many relationships can you identify? Warren Beatty, Christopher Lee, Lauren Bacall, Angelina Jolie, Isabella Rossellini, Loretta Lynn, Debbie Reynolds, Ian Fleming, Shirley Maclaine, Crystal Gayle, Stanley Baldwin, Peter Sarstedt, Jon Voigt, Francis Ford Coppola, Ginger Rogers, Nicolas Cage, Ingrid Bergman, Rudyard Kipling, Richard Briers, Tippi Hedren, Rita Hayworth, Shimon Peres, Carrie Fisher, Eden Kane, Melanie Griffith, Terry Thomas.
What year when written in Roman numerals uniquely contains one of each symbol in descending order?
Irrespective of sheet size, what is the most number of times a square piece of normal stock paper can be folded in half? (And not by repeatedly folding and unfolding it which would be cheating...). And as a supplementary question, what's the most number of folds in half achieved for a piece of normal stock paper irrespective of length and shape? (achieved in 2004)
What did each of these brand names originally represent? Athena, Nike, Vesta, Mercury, Vulcan, Flora, Mars.
With no pre-selection, and excluding February 29th, what's the smallest number of people in a group required to ensure a better than even chance of at least two of them having the same birthday? That's birthDAY, not birthDATE.
How many different batting orders are possible in a team of eleven cricketers?
Do bullets fired straight up into the air take longer to go up or to come down, or the same time, and why?
What famous confrontational sporting ritual traditionally began (until changed in 2005) with the words, "Ka Mate Ka Mate.."? (mate is pronounced 'mattay')
How many of the novels can you name in which these characters appear? (they get harder...) Quasimodo, d'Artagnan, Scarlet O'Hara, Phileas Fogg, Jim Hawkins, Yossarian, Lemuel Gulliver, Randall McMurphy, Philip Pirrip, Jude Fawley, Captain Ahab, Eliza Doolittle, Blanche Dubois, Edmund Dantes, Holly Golightly, Percy Blakeney, Nick Carraway, Leopold Bloom, David Balfour, Charles Ryder, Holden Caulfield, Richard Hannay, Elizabeth Bennet, Tom Joad, Maggie Pollitt, Becky Sharp, Dorothea Brooke, Josephine March, Rupert Birkin, Maggie Tulliver, Jimmy Porter, Arthur Seaton.
Put these British aristocratic titles in the correct order of seniority - Marquess, Earl, Viscount, Prince, Duchess, Lord, Baron, King, Marchioness, Duke, Prince, Queen, Lady, Earl, Princess, Baroness, Viscountess, Countess.
What do these names have in common?..... Winnebago, Tobacco, Chinook, Laguna, Mobile, Mono, Yazoo.
A gameshow contestant reaches the final challenge: Two security guards are each holding identical closed brief cases. In one there is $1m of banknotes; in the other a few of last week's newspapers. The guards know what is in each case. The contestant is told that one guard will lie and the other will tell the truth - but not which guard is which. He is then told that he can ask one guard just one question, and then he must choose one case or the other. What question should he ask? (There are two possible questions we know of (thanks to John Fisher for suggesting the second one.) A man took the bus every weekend to go fishing either to the lake or the river. Initially he tried to guess which would offer the best conditions, but frequently guessed wrong. So he decided that as the buses to each place ran every ten minutes, and from the same bus-stop, he'd simply leave it to fate, and jump on the first bus that came along. After several weeks he was puzzled that he hardly ever got to go to the lake - in fact it was only about one week in ten - despite the fact that he got to the bus-stop at all different times, and that all the buses to both places ran on time (this is only a story...). So why was this? How many times would a football rotate if rolled around the middle circumference of another football of the same size? (Please note that the answer to this question was corrected 17 Oct 2012.) Numerically, what's the difference between a hind and a hart? Why do buses come in twos and threes? Why do we clink glasses when we say 'cheers' (or 'skol' or 'good health' etc)? It is said to be bad grammar to finish a sentence with a preposition (ie., a word that expresses the relation of one noun or pronoun to another, 'of', 'with', 'to', 'over' etc). Can you think of a sentence which makes sense and finishes with seven consecutive prepositions? (ack. The Bean) A new street is built with one hundred new houses, numbered 1 to 100. How many number 9s are required to number all the houses? (upside-down 6s are not allowed) (ack. Neal Stothard) Can you be mathematically certain that at least two people in the UK have exactly the same number of hairs on their head, and why so, or not? There are several fascinating similarities between the assassinations of American Presidents Abraham Lincoln and John F Kennedy - which ones can you name? What politician, noted for his wit, when told that his trouser fly was open said, "Dead birds don't fall out of their nests..." ? There are four (that we know) ten-letter English words that can be made from the top row of letters on a normal QWERTY keyboard, what are they? (a clue for one of them is in the question) Why are buttons on women's and men's clothing such as jackets and shirts on different sides (and for the same reason, why do bras fasten at the back?) A part of a wheel is a SPOKE, another word for people is FOLK, so how do you spell the word for the white of an egg? What do these words have in common: pint, skeleton, limited, restaurant and oblige? A man knew that he was bankrupt the moment he stopped his car outside a railway station. How? A stamp collector paid$100,000 for a stamp and then deliberately destroyed it. Why?
Two chess masters played fifteen consecutive games of chess. No games were drawn, every game was finished, yet both players won and lost the same number of games as each other. How could this happen?
There are five 'f's in the next sentance, and they're two mistakes in this one. - "It's often easy for folk to miss the finer points of life." - How many mistakes are there in the first sentence?
Can a man marry his widow's half-sister?
A bucket and spade together cost £25.50. The spade costs £20 more than the bucket. What is the price of each?
A brick weighs 1kg plus half a brick. How much does it weigh?
George Bernard Shaw's 'FISH' (George Bernard Shaw devised this alternative spelling for the word 'fish'): GHOTI. Explain how this spells 'fish'.
Why is the sum £88.88 special? (And for those with knowledge of Scotttish and Channel Islands currency, £190.38?) This question is based on UK currency as at May 2005 (no doubt there will be changes in the future).
Complete the sequence: O, T, T, F, F, S, S, ...
Five Ands: construct a sentence which makes sense (and state the scenario) which includes the word 'and' five consecutive times.
What do these words have in common? CALMNESS - INOPERABLE - DEFER - BURST - LAUGHING - STUPID.
Which one of these letters is the odd one out and why? (two possible different answers): A B C M N O T U V.
AEIOU word puzzle: There are several words in the English language which have one of each of the vowels (aeiou) in the right alphabetical order. How many do you know?
Try the expressions derivations quiz.
See also the Quizballs quizzes with free questions and answers - quicker questions for trivia and pub quizzes, and learning and amusement of course.
### puzzles and tricks
#### hoover dam word puzzle
A sign at the Hoover Dam complex contains a word combination (three words joined together) which includes five consecutive double letters - what is the word?
The clue is in the question.
(Thanks M Verbo/C Preposi for the information enabling the creation of this puzzle.)
#### triangles puzzle
Equipment: Six pencils/pens (or six matchsticks or cocktail sticks) of equal length.
Arrange the pencils/sticks as in the picture below.
Now make four equilateral triangles (same length sides) using the pencils/sticks.
Each triangle must be the same size, and every side of each triangle must be the same length as the sticks provided.
No breaking sticks/pencils allowed.
#### shovel puzzle
Equipment: Four matchsticks (or four cocktail sticks or four pens/pencils) and a coin.
Make the shape of a shovel, containing a coin.
Now make the same shovel, no longer containing the coin, by moving only two sticks.
This is not a trick question, although there is a lateral-thinking aspect to the solution.
(Thanks H)
#### the '1234567890=100' puzzle
This puzzle (thanks L Henderson) is the sort which appears in emails from time to time. Most people would regard this as a trick question, or a lateral thinking question, so expect groans from your victims if you present it as a straightforward mathematical puzzle.
Using the least number of mathematical symbols make this formula correct:
1 2 3 4 5 6 7 8 9 0 = 100
There are some very clever 'trick' or lateral-thinking answers which will make you say "Doh!..", and then several equally very clever non-trick mathematical answers, submitted by readers, to whom I am very grateful.
#### six puzzle
This is a lateral thinking puzzle.
The solution to the following questions is the same. What is it?
1. How do you deduct 3 from 9 by adding something close to 5?
2. How do you deduct 4 from 10 by adding something close to 51?
#### paris in the spring
Quickly, what do the words in the triangle say?
Most people will say "Paris in the Spring".
People tend to make this error even without seeing the introductory heading.
This tendency demonstrates how we read: not by looking at each word separately, but by seeing and recognizing several words at a time, especially if the phrase is an understandable concept.
This unconscious quick processing by the brain is normally helpful because it saves time, but on occasions it can fool us.
The puzzle shows how vulnerable we are to false assumptions, and particularly that sometimes we lazily rely on our brain's ability to process information extremely quickly, when really we should be over-riding this unconscious processing by consciously focusing on the detail.
The exercise will work with phrases other than Paris in the Spring, provided you keep to the same pattern.
#### how many 'f's?
This puzzle has been fooling people for decades. You can use it to demonstrate how our mind sometimes plays tricks on what we believe. The puzzle can also be used to support themes of concentration, accuracy, assumptions, and creative or lateral thinking (which can be employed to devise an alternative method of arriving at the right answer; for example using the 'find' feature in your computer program).
The layout is probably important in the way that it works. Show the box below to people and ask them to read the words and count the number of times the letter f (or F) appears. Most people get it wrong. Try it yourself, and then check your answer carefully. It's not a trick question - the trick is the way that the mind works in identifying letters.
How many 'f's?FINE POINTIt is easy to miss the finer points in life. Folk are frequently guilty of falling into this trap.
The letter f appears eight times in the box. People commonly count seven, by failing to see the last but one f.
Did you?
And if you found that one too easy, try this one.
Again, how times does the letter f (or F) appear in the following item?
Finished files are the result of years of scientific study combined with the experience of years.
Did you find all six?
(Thanks to my Dad, who kept the first one on a card which he was given on a training course in the 1960s. The second is perhaps more widely known, and featured in Frank Johnson's Notebook column in the Daily Telegraph, 8 March 2003. If you know who devised either of these clever little posers please tell me.)
Answer - yes, some people simply cannot see them all no matter how hard they look.
#### all the 1's puzzle
The puzzle is simply, what surprising result does the calculation 111,111,111 x 111,111,111 produce?
This puzzle is made all the more intriguing by the difficulty in finding a readily available tool that can handle the calculation. Even MSExcel is unable to calculate or show such big numbers. (Apparently Excel can be given this very big number calculation capability via an add-in, for example XNUMBERS 4.7 available from www.digilander.libero.it/foxes/SoftwareDownload.htm, although I've not checked this and cannot be held responsible for any problems arising from trying it - ack J Smallwood).
And R Lennox kindly informs me that, "...those of us who are not microsoft-challanged can easily calculate 111,111,111 x 111,111,111. Most linux (unix) command-lines will reveal that typing 'echo 111111111*111111111 | bc' gives (the answer).."
Answer. (Thanks D Harpell for the puzzle)
#### quick maths puzzle
This can be done with a pencil and paper by people who can do long-division (engineers, people over forty years of age, etc); otherwise it's advisable to suggest that people use a calculator to be sure of completing the exercise reliably and within three hours (ordinarily it just takes a minute or two). The puzzle can be given to any number of delegates at the same time to do individually, so it's ideal for diversions and mental warm-ups in training and meetings. Instructions:
Write down any three-digit number (genuinely three digits, ie, not beginning with 0), then write it down again, so as to give a 6-digit number, for example 123123.
Divide the six-digit number by 7. (It adds to the effect if the facilitator says: "Don't worry about the remainder; there won't be one.")
Next, divide the answer by 11. (Again the facilitator can say: "Don't worry about the remainder; there won't be one.")
Next, divide that answer by 13 (Again: "Don't worry about the remainder; there won't be one.")
Recognise the number?
(Here's why it works: the six-digit number is 1,001-times greater than the three-digit number, which seems logical when you realise that 1,000-times the three-digit number would add three zeros, and another 'one-times' replaces the three zeros with same first three digits. When you divide by 7, then 11, then 13, this equates to dividing by 1,001 (7 x 11 x 13 = 1,001). The trick is achieved simply by reversing reversing the calculation: 123 x 1,001 = 123123. Then 123123 ÷ 1,001 = 123.) (Thanks Terry Moran)
#### mobius strip (mobius band) trick - (technically möbius, pronounced 'merbius')
This is an amazing trick, ideal for parties, social gatherings, light relief or ice-breakers at meetings, and bar-bets. It is two puzzles in one, that will amaze and astound, and will win you money and drinks, favours, fame and admiration, if you aspire to such things. And this free easy puzzle is fantastic for kids parties too. In fact this is probably the best free trick in the history of the world.
Cut a strip of paper so that its length is at least ten times that of its width - something around ten inches by one inch wide is fine.
Puzzle 1: The strip clearly has two sides, yes? If you were asked to write number 1's all along one side of the strip, and number 2's all along the other side of the strip this would be possible, yes? So could I prevent you from doing this simply by joining the ends of the strip to create a ring or band shape?
Puzzle 2: the strip, (or now a band) is made of paper and if you cut or tear it in half you will have two separate halves, yes? And these two separate halves will actually be separate, so that they can be placed in two separate pockets, yes? So, again, simply by joining the ends of the strip to form a band, can I cut or tear this paper in half, with a continuous cut from a pair of scissors, or a continuous tear, so that you will not be able (unless by force of course) to separate the two halves? More incredibly, can I do this so that you don't actually have two halves at all? So that you actually still have one joined together strip?
You bet. And here's how.
#### age maths trick (calculator required)
Pick any number between 1 and 100,000 (maybe the last four or five digits of your phone number).
Multiply it by 2.
Subtract the four digit year that you were born.
*1763 and 1762 work for the year 2013. Add 1 for each year after this, for example in 2014 use 1764 and 1763.
#### spelling tricks
1. Ask someone or a group: Spell the word 'silk'. (They should spell out the letters: S, I, L, K.)
Then ask them: What do cows drink?
2. Ask someone or a group: Spell the word 'coast' (They should spell out the letters: C, O, A, S, T.)
Then ask them: What do you put into a toaster?
#### phone number maths trick
This works for landline numbers which (without the area code) are 7 digits long.
1. Using a calculator, key in the first three digits of your phone number (not the area code)
2. Multiply by 80
4. Multiply by 250
7. Subtract 250
8. Divide the answer by 2
#### co-ordination puzzle
While sitting down (or standing if you have good balance), lift your right foot off the floor and make clockwise circles with it. At the same time, repeatedly draw the number 6 in the air with your right hand. Your foot will change direction and without an awful lot of practice, there's nothing you can do to prevent it.
This effect seems to be because drawing the number 6 is effectively a counter-clockwise movement which the brain can't reconcile easily with a clockwise one (a bit like patting your head and rubbing your stomach at the same time). If you draw the six from the middle and end with the up-stroke instead, it doesn't conflict with the clockwise foot motion, because the 6 is now a clockwise motion too. What's strange is how we've evolved to enable same direction movements with different limbs, and to resist opposite ones - There doesn't seem to be a survival benefit from this, unless it's a bi-product of an overall more co-ordinated (and therefore more efficient, quicker, athletic) movement capability, which would of course have been a survival aid.
#### association puzzle
Do these sums in your head. There is no need to write the answers down or remember them.
What is: 15+6?
3+56?
89+2?
12+53?
75+26?
25+52?
63+32?
123+5
Now, think of a tool and a colour. Your answer is. (Thanks M Ordway)
#### utilities puzzle
Draw three houses in a horizontal row. Draw three utilities suppliers beneath them: Gas, Water, Electicity. You should now have six points or boxes on your sheet of paper or flip chart. The challenge is to connect each house to each utility supplier without any of the nine connection lines crossing. Answer.
#### mental maths trick 1
Think of a number between 1 and 10. Multiply it by 9. If you have two digits add them together. Subtract 5. Convert your number into a letter, on the basis that A = 1, B = 2, etc. Think of a country that begins with that letter. Think of an animal that begins with the second letter of that country. Your answer is. (Thanks R Corovic)
#### egg trick
How to balance an egg on its end with no visible means of support:
You need just a few grains of salt. Make a tiny pile of salt on a flat surface and balance the egg on the pile. Then carefully blow away the excess salt, leaving just the few grains actually supporting the egg. (Obviously this needs preparing in advance - if pressed to repeat the trick, place the egg down hard enough to break the shell, which will also enable it to balance).
You can prepare a banana so that when someone removes the skin the banana inside is already sliced:
You need just a clean pin. To make each slice, insert the pin through the banana skin, but not so deep as to enter the skin on the other side. Move the pin sideways in a see-saw motion, using the entry point of the skin as a pivot. Replace the banana in the fruit bowl.
A more sophisticated method is as follows: Use a needle and thread rather than a pin. The aim is to thread a loop around the banana under the skin for each slice required. Consider the banana skin to be composed of several angled facets. Insert the needle at one facet join where you wish to slice it, and bring it out at the next, so that the thread runs under the skin. Re-insert the needle in the same hole and go along to the next join and so on. Eventually bring the needle out of the original hole. There is now a loop of thread all around the banana under the skin. Hold both ends and pull gently. The banana is sliced through using the cheese-wire principle. Repeat the process for each slice. (Thanks Michael Green)
#### cartoon quiz
How many clues do you need to guess this eponymous cartoon series:
• Cher appeared as an animated guest star.
• It was first shown on 13 Sept 1969 in the USA.
• The central character's voice was provided by the late Don Messick.
• The central character's name was inspired by the refrain of Sinatra's song 'Strangers in the Night'.
• Don Messick also provided the voice for Muttley of Wacky Races.
• A screen kiss between the Daphne and Velma was cut from the show.
• The 13 ghost characters that appeared in the series inspired the film 'Ghostbusters'.
If you haven't guessed yet here's the answer and a few more details.
#### pool puzzler
Six friends visited their local club to play at a pool tournament. The competition entry fee was £10 per person. Prize money was £250 for the winner, £100 for the runner-up, and £50 for third-place. There were no other prizes. None of the friends won a single game. There were no disqualifications, and yet the friends came away collectively £150 in profit from having played. How? Answer. (Adapted from a puzzle from Alex Sallustio, thanks)
#### whodunnit?
Three of these statements are untrue, so whodunnit?
Mr Red: "Mr Blue did it."
Mr Blue: "Mr Red did it."
Mr Green: "Mr Blue's telling the truth."
Mr Yellow: "Mr Green's not lying."
#### three-digit maths trick
Write down any three-digit number, with different first and last digits. Reverse it. Subtract the smaller number from the larger one. Write down the answer. Reverse it (including the zero at the beginning if less than a hundred). Add together both numbers. Your final answer is.
#### nail puzzle
This fantastic lateral thinking puzzle makes a great quick warm-up. It will also win you a fortune in pubs and bars the world over. It is essential you practice this before using it in front of an audience.
The challenge is simply to balance 14 nails on one single nail which is fixed upright in a block of wood. The nails must all be the same size - any length provided they have flat heads.
The suggested scenario is that due to a last-minute hitch where you are exhibiting your products (nails), you (your team) have just (say three to fifteen) minutes to devise a way of displaying all 14 nails using only the single fixed nail as a support. None of the other 14 nails can touch anything other than the other loose nails and the fixed nail.
Teams of three are good for this game as it's high-involvement, trail and error, and hands-on; more than five per team will cause people to be left out. Issue each team with fourteen nails and a block of wood with the fifteenth nail hammered into position. Different types and lengths of nails may change the number of nails required, but there must always be an odd number including the fixed nail. (Thanks to John Rivers for this great puzzle). Answer.
#### complete the formula
Use only one of these symbols (+ - × ÷) to complete the formula: 10 10 10 = 9.50 (Thanks Alex Guild) Answer.
#### fairground chequers maths puzzle
This is an old fairground game, but can you calculate the mathematical chances of winning with a single go? To win, you must toss a 1 inch diameter coin onto a chequered board comprising 2 inch diameter squares; the coin must come to rest entirely inside a square, not overlapping any other square. (Thanks DC) Answer.
#### the necker cube
Everyone's seen this shape before, but there's more to it than first seems. The Necker Cube provides a fascinating demonstration of how the brain works on a sub-conscious level whether we want it to or not. Stare at it for a few seconds and it will flip into its alternative perspective. Wait and it will flip back again. It's unlikely you'll be able consciously to change the perspective that your brain chooses to see, although blinking might trigger the brain to 'refresh' the image.
#### balloon and knitting needle trick
How do you stick a knitting needle through both sides of an inflated balloon without the balloon bursting? Answer.
#### microsoft excel trick
This works on MSExcel 97 (if you can still get hold of a copy). Start program. Press F5. Enter reference X97:L97. Press Enter or Okay. Press Tab once. Hold down Shift and Control and at the same time click on the Chart Wizard icon (looks like a coloured 3D graph). Move mouse to walk on the moon. F12 to exit.
#### weird maths
Three men eat at a restaurant. The bill comes to £25. They each pay £10. When the waiter brings the £5 change they take back £1 each and leave a £2 tip. So each man has paid £9, which totals £27. The waiter has the £2 tip, which makes £29, so where's the other £1 gone? Answer.
#### farmer's puzzle
A farmer has a dog, a sack of grain and a live chicken, all of which he must take across a river. The boat will only carry him and one of the things at a time or it will sink. Without the farmer, the dog would kill the chicken, and the chicken would eat the grain. How does he get all three across safely to continue his journey? Answer.
#### coin and bottle trick
Take an empty beer bottle and a small coin which is wider than the mouth of the bottle but no wider than the rim (a British penny is ideal). How do you move the coin without moving the bottle, touching or blowing the coin, or using another object to contact the coin and move it? Answer.
#### string-cutting trick
You need some string or cord that's normally impossible to break with bare hands. Cut a 2-3ft length. Wrap one end clockwise three or four times around the base of your left thumb to secure it. The loose end should hang from the back of your thumb, not over the front.
Drape a large loop across your left palm so that the loose end hangs over the back of your hand between your left hand thumb and forefinger. Bring the loose end underneath palm and feed it up through the bottom of the 'U' of the loop, from the back to the front.
Pull and tighten string, so that the crossing point is in the centre of your palm, keeping left hand firm in a karate-chop position. Wrap the loose end firmly around your right hand. Pull sharply down with right hand, keeping left hand firm. The string will be cut at crossing point. (Left-handers obviously reverse positions.)
Depending on your strength and confidence you'll be able to cut extremely strong nylon cords this way.
The point of the trick is to demonstrate how innovation and positive approach can achieve the seemingly impossible.
#### amazing fact
There is more computing power in a happy birthday sound card than the whole world in 1952. (Source - Innovations magazine 1995)
#### impossible paper trick
(Do not show the audience this preparation) Start with a paper rectangle, any size, 9" x 6" is fine. Make two right-angle cuts to the exact centre on one long side, at 3" and 6". Make one right-angle cut to the exact centre on the other long side at 4.5". Lay the sheet flat, fold over the central flap making a neat hinge and fold it back.
Lift the sheet by the two short sides, with the flap away from you, and twist one of the L-shaped ends 180 degrees (half a full turn).
Lay the sheet flat again, and fold the flap down both ways to create a hinge. The flap should now be erect, with half of the cut-away on each side - which looks like an impossible construction. This is what you show your audience. Ask them to explain it.
#### word colour trick
Read out (at normal pace) the colour of each word, not the word itself, without making a mistake.
Red Yellow Blue Green Yellow Red Green Blue Green Red Blue Yellow Yellow Green Red Blue Yellow Blue Red GreenYellow Green Red Blue Red Green Blue Green Green Yellow
If you want to beat the trick, squint your eyes to blur the words (Thanks Dave Skinner)
#### anagrams and anagram finder
"All the life's wisdom can be found in anagrams. Anagrams never lie." (Anu Garg - real name, not an anagram apparently).
Particularly good fun if you use work-colleagues' names - and amazing how often really fitting anagrams crop up. An amusing diversion during meeting breaks if you're using online projection equipment.
Anagram finder - online and free - great fun for meetings and training sessions.
#### mind-set trick
Try this for yourself. (If you do it with a group use a flip chart.) Draw a circle. Divide it into two equal parts, (answer is obviously one line dissecting across the centre). Next draw an equilateral triangle (three sides same length) and divide into three equal parts. Think about it before you read on.
Answer is tricky for some - three lines from centre outwards to corners. Next draw a square and divide it into four equal parts (easy - two lines dissecting up and across to make four quarters). Now draw another square. Divide it into five equal parts. (The point is to demonstrate how the mind can get 'stuck' in a certain thought pattern.) Got it yet? Answer.
#### four-digit maths trick
A completed set of numbers could look like this:
8327 Ask the other person to write down a four digit number in view of observers - a flip chart is ideal. On a separate slip of paper, you then deduct 2 from their number and put the number 2 in front = 28325. Write this number on the slip, fold it and give it to the other person without them or anyone else seeing the number. 9526 Ask the other person to write another four digit number beneath the first one. 473 You write a number in the third column so it makes a total of 9999 when added to the second row. (note that in this case the second row first digit is nine therefore no figure needs be written beneath it - a zero here might give them a clue as to your method). 7539 Ask them to write another four digit number. 2460 You write a number in the fifth column so it makes a total of 9999 when added to the fourth row. 28325 Now ask them to total all five columns - then ask them to look at the slip of paper. 28325 - same number.
You can extend the trick to seven rows (deduct 3 and put a number 3 in front of the first number), or nine rows (deduct 4 and put a number 4 in front of the first number), and so on.
#### incredible planning tool - can it be true?
This is the specification for the most incredible, sophisticated planning and communications tool yet invented: It's portable - so light don't even notice it your pocket or brief case. Its life is more than one-hundred times greater than the current best re-chargeable power-packs. It is extremely durable - if dropped from 50 feet onto concrete it'll be good as new within a minute or two at the longest. It's so intuitive that anyone can use it immediately without training. You can use it on a plane - even during take off. It uses a remarkable data input method as fast as an experienced qwerty keyboard operator, and yet requires no keyboard skills. It handles graphics as easily as text and can even handle 3-D modelling and complicated calculations. It is compatible with any paper output, even a bus-ticket or a table napkin, and is universally adaptable to any reader format. It is completely wireless, already available all over the world, thanks to a distribution network greater than Microsoft's, and comes in hundreds of model variants to suit all styles and egos - you can even get gold-plated ones. It costs a fraction of a penny per day over its lifetime, and if you lose it, its inherent unbreakable security will leave no trace of confidential files or personal history. Replacements are no problem because you can afford to keep a couple spare with you all the time. If you have not guessed what it is yet, here's the answer.
#### team building games
For original and enjoyable team building games, go to the team building games section. Includes team building ideas and games formats for treasure hunts, mime acts, juggling, yoyos, newspaper towers and bridges, problem solving and more.
quizballs quizzes with free questions and answers - quicker quiz questions for trivia and pub quizzes
free complex difficult puzzles
free expressions derivations quiz
tips on using puzzles and games in business and training activities are on the team building games section
quizballs.com - free quizzes website operated by businessballs
The use of this material is free for self-development, developing others, research, and organizational improvement. Please reference authorship and copyright of material used, including link(s) to Businessballs.com and the material webpage; see authorship/referencing above. This material may not be sold, published, or reproduced online. Disclaimer: Reliance on this material and any related provision is at your sole risk. Alan Chapman assumes no responsibility for any errors or damages arising. Seek qualified advice for any action entailing potential liabilities. Where appropriate retain this notice on copies. See about us for detailed terms.
#### hoover dam word puzzle
Flooddoorroom.
I am grateful to M Verbo/C Preposi for the information enabling the creation of this puzzle.
If anyone can send a photograph of this word on a sign at the Hoover Dam - please email it to me.
triangles puzzle
You obvously need to hold the pencils in place, but the puzzle does not forbid this.
Very rarely will anyone consider building four triangles in 3D (three-dimensional) as a pyramid.
People's brains tend to stay fixed on a flat two-dimensional puzzle.
shovel puzzle
Answer: slide the middle stick a half-stick-length right (or left), then move the top now unconnected stick to the opposite downward corner to make the new shovel. The puzzle is difficult because most people naturally imagine moving sticks to entirely different positions, and rarely consider shifting a stick only half of its length.
the '1234567890=100' puzzle
(Using the least number of mathematical symbols make this formula correct: 1 2 3 4 5 6 7 8 9 0 = 100)
Best answer: 1 2 3 4 5 6 7 8 9 0 ≠ 100
A slashed 'equals' sign is the mathematical symbol for 'does not equal'. If the above code does not display correctly it can alternatively be shown as: =/=
Alternatively, very cleverly, and only one additional pen-stroke (thanks M Khan, Aug 2014):
1234567890 = 100x (the x symbol represents a quantity yet to be determined)
Thanks C St John for this 'non-trick' answer:
1x(2+3)x4x5+(6x7x8x9x0) = 100
Given strict application of mathematical rules for the order of calculations - see BODMAS - the above solution can be reduced as follows, because the rules dictate the multiplication be calculated before the addition:
1x(2+3)x4x5+6x7x8x9x0 = 100
And here is an entirely different and equally brilliant suggestion (thanks Becky Nelson):
1+2+3+4+5+6+7+8x9+0 = 100
Becky explains the BODMAS effect: because of order of precedence the multiplication of 8 x 9 occurs first resulting in 72; the other numbers add up to 28, which when added to 72 makes 100.
And extending the first idea:
1x(2+3)x4x5+6789x0 = 100
This is a lateral-thinking solution if the question is taken to imply that each digit stands alone, but it's another option, depending on how strictly the question is interpreted.
Here's another clever suggestion (thanks D Robinson):
1x2x3x4+5+6-7+8x9+0 = 100
Again the solution must be employed with the BODMAS sequence for performaing the different calculations, which in this case means multiplication first, then addition, then subtraction.
And a further brilliantly simple and elegant suggestion (thanks D Jackson). This one has only five symbols (apart from the = of course) and just uses addition and subtraction:
123+45-67+8-9+0=100
Here below is a fresh approach, and a wonderful example of lateral thinking (thanks V Chaves). The validity of the solution depends a broad interpretation of the word 'formula' in the question. It certainly uses very few symbols and the mathematics are difficult to dispute:
123456789x0=10x0
By similar logic the following also works: 12345678901x0=0
Here are a couple of solutions (thanks R Von Der Emden) based on a very clever lateral thinking approach:
1 2-3+4-5-6+7-8+9 0 = 100 (translates to mean 100 = 100)
1 23-45-67+89 0 = 100 (also translates to mean 100 = 100)
(In both cases on the left side of the equation the figures 1 and 0 remain outside of the formula which separates them. The formulae from 2 to 9 become the second 0 in the number 100.)
If you can suggest a different 'non-trick' mathematical answer, or any other lateral solution, especially using fewer symbols please send it.
I am grateful to all above for these clever contributions.
six puzzle - The solution to the following questions is the same. What is it?
1. How do you deduct 3 from 9 by adding something close to 5?
2. How do you deduct 4 from 10 by adding something close to 51?
SIX
(IX is the Roman numeral for 9, and X is the Roman numeral for 10.)
There are eight Fs in first puzzle, and six Fs in second puzzle.
The F in 'of' can be difficult to see until you know the answer, and in the first puzzle especially in the 'of falling' words, because the eye is drawn to the F in 'falling' and can miss the F in the preceding 'of'. Amazingly the first puzzle can still fool people when all the Fs are coloured red.
How many ' f's?FINE POINTIt is easy to miss the finer points in life. Folk are frequently guilty of falling into this trap.
Finished files are the result of years of scientific study combined with the experience of years.
###### all the 1's puzzle answer
111,111,111 x 111,111,111 = 12,345,678,987,654,321
Twist the strip through 180 degrees, ie., half a whole turn, before joining the ends. For the purposes of the tricks you can join the strip with glue (in which case use a glue that sets quickly), sticky tape (a tape you can tear if you do not have scissors), or two staples (aligned lengthways, not sideways across the strip, each close to an edge, leaving a gap between them). You have now made a Möbius Strip, or Möbius Band, which amazingly now has only one side. Try it. It is not possible to colour or number or mark two different sides along the whole of the length of 'each side'. There is now only one side. Feed the band between your finger and thumb through a whole revolution and you will see that what were once two separate sides now pass underneath and touching your thumb.
Now for the cleverest part of the trick: Cut or tear the band in half along its length. You will need to tear or cut it carefully while feeding it through your fingers; you cannot cut it with one motion. You will be left not with two separate halves; not even two joined halves; you will be left with one big band.
Finally you can cut the new big band in half again - you will be left with two bands linked together.
The Mobius Strip or Band has in fact been around for hundreds of years. According to scientific reports and writings this is the story: the Mobius strip was named after astronomer and mathematician August Ferdinand Möbius (1790-1868), who was a professor at the University of Leipzig. It seems he devised his strip in September 1858, and published his discovery in 1865. Interestingly, it seems that coincidentally and separately a German mathematician called Johann Benedict Listing (1808-1882) is said also to have made the same discovery in July 1858, which he published in 1861 while working on theories of another great mathematician, Leonhard Euler, who devised the Euler puzzles and Euler's Rule featured elsewhere on this site.
spelling tricks
Did you say 'milk' and toast? The answers are 'water' and 'bread'.
association puzzle
Did you think of a red hammer? Apparently the vast majority of people do. The reason why this works would seem to be that the mental calculations are a distraction to clear the mind, enabling the most likely answers for each category to emerge upon prompting (red being the most commonly 'spontaneously thought of' colour, and hammer being the most commonly 'spontaneously thought of' tool). Thanks Kaz. If you know any more about this is please let me know.
utilities puzzle
This classic puzzle which has been around for hundreds of years, although it was obviously not known as the Utilities Puzzle until relatively recently. Strictly speaking it is impossible to solve the puzzle using two dimensions on flat piece of paper; there will always be a minimum of two crossed connections.
There are however two great lateral thinking solutions:
1. Take the final line (that would otherwise cross another) through the utilities and/or houses themselves, which unless specifically outlawed in the instructions would not constitute a cheat.
2. The puzzle can be solved without taking any lines through buildings, if the utilities and houses are on the outer surface of a ring torus (three-dimensional doughnut) shape. You can create the torus effect simply by making a hole in the paper centrally between all six connection points and folding flaps around the edges of the hole and the edges of the sheet, so as to take certain lines through the hole and around the back of the sheet to make the connections. More explanation and ring torus solution here.
mental maths trick 1
Elephant (No? Emu?.......).
mental maths trick 2
5,000? Wrong. Try it again. The correct answer is 4,100. The mind knows that the final 10 will have a 'rounding-up' effect, and expects it to impact the 1,000's instead of the 100's. The mind fails to calculate the final figure properly because it's locked into an expectation.
cartoon quiz
Scooby-Doo, Where Are You! Featuring Scooby-Doo, Shaggy, Fred, Velma and Daphne. Scooby-Doo rhymes with Sinatra's Doobie-doo refrain in Strangers in the Night.
pool puzzler
They were the musicians in the band.
whodunnit
Mr Blue did it.
three-digit maths trick
nail puzzle
Lay one nail on the table, and on it at 90 degrees (ie., perpendicular) lay all the other nails except one, alternately each side with points furthermost. There must be an equal number of nails on each side, and they must fill the length of the nail on which they lay, so adjust the quantity of nails to ensure this happens. (Now you see why you need to practice this.)
Lay the last nail on top of the first nail pointing the opposite direction (the last nail is shown in red on the diagram).
Gently lift the assembled nails by holding the ends of the top and bottom nails. As the perpendicular nails sag down to an angle of around 45 degrees, amazingly the whole assembly locks itself together. You can now balance the assembly on the supporting nail in the block. (The balance point is extremely forgiving, due to the counter-balancing effect of the nails hanging down lower than the point of support.) The diagram shows a side view.
Okay, it's only got 12 nails but you get the idea...
complete the formula
10 T0 10 = 9.50 (9.50 in this context is an expression of time - 0950hrs - not a decimal number; the brain of course instantly fixes on the number as a pure decimal number and looks for an impossible solution.)
fairground chequers maths puzzle
The calculation is very simple - the centre of the coin can be no closer to the edge of a square than half an inch. The 'win-zone' is therefore a 1 x 1 inch square defined by a half inch border inside each 2 inch square. The total area of each chequered square is 2 x 2 = 4 square inches; the win-zone in each is 1 x 1 = 1 square inch; so the chances of winning are exactly 1 in 4, or 25%, or 3 to 1 against.
balloon and knitting needle
You need to prepare the trick in advance. Inflate the balloon and knot the end. Stick an inch-long strip of Sellotape (or better still matt-finish Scotch cleartape) to each side of the balloon at the proposed needle entry and exit points. You can now pierce the balloon with a (sharp) knitting needle and then again on the other side, without it bursting. Practice first, if only to develop your confidence.
weird maths
the answer is that the figures will not add to £30 because they are not from the same equation. Equation 1: What's been paid is £25 for the meal - which is in the till, and £2 for the tip - in the waiter's pocket, leaving the men with £1 each, ie £3, which all adds up to £30. Equation 2: The men have each paid £9 for the meal and the tip together, ie £27, and they each have a £1 in their pocket, ie £3, which all adds up to £30.
farmer's puzzle:
he takes the chicken and comes back; then he takes the grain and comes back with the chicken; then he takes the dog and comes back; then he takes the chicken.
coin and bottle trick
Drip some liquid onto the coin so that a seal is made between the coin edge and the mouth of the bottle. Clasp your hands around the bottle and wait a few seconds. The air inside the bottle expands from the heat of your hands. As the pressure builds, air escapes bubble by bubble, by repeatedly dislodging the coin.
mind set trick
If you try this with a group ask for people not to shout out answer; it will spoil it for those who get really stuck. Strangely many people will struggle for ages because they get stuck in the same mind set used for the previous square and triangle solutions (whereas the answer is obviously four horizontal or vertical lines to make five equal sections).
incredible planning tool
a pencil
The use of this material is free for self-development, developing others, research, and organizational improvement. Please reference authorship and copyright of material used, including link(s) to Businessballs.com and the material webpage; see authorship/referencing above. This material may not be sold, published, or reproduced online. Disclaimer: Reliance on this material and any related provision is at your sole risk. Alan Chapman assumes no responsibility for any errors or damages arising. Seek qualified advice for any action entailing potential liabilities. Where appropriate retain this notice on copies. See about us for detailed terms. | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.3623043894767761, "perplexity": 3096.8521778353397}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2019-13/segments/1552912201904.55/warc/CC-MAIN-20190319052517-20190319074517-00257.warc.gz"} |
https://modeloriented.github.io/ingredients/articles/vignette_describe.html | # Introduction
We adress the problem of insuficient interpretability of explanations for domain experts. We solve this issue by introducing describe() function, which automaticly generates natural language descriptions of explanations generated with ingredients package.
# ingredients Package
The ingredients package allows for generating prediction validation and predition perturbation explanations. They allow for both global and local model explanation.
Generic function decribe() generates a natural language description for explanations generated with feature_importance(), ceteris_paribus() functions.
To show generating automatic descriptions we first load the data set and build a random forest model classifying, which of the passangers survived sinking of the titanic. Then, using DALEX package, we generate an explainer of the model. Lastly we select a random passanger, which prediction’s should be explained.
library("DALEX")
library("ingredients")
library("randomForest")
titanic <- na.omit(titanic)
model_titanic_rf <- randomForest(survived == "yes" ~ .,
data = titanic)
explain_titanic_rf <- explain(model_titanic_rf,
data = titanic[,-9],
y = titanic\$survived == "yes",
label = "Random Forest")
#> Preparation of a new explainer is initiated
#> -> model label : Random Forest
#> -> data : 2099 rows 8 cols
#> -> target variable : 2099 values
#> -> predict function : yhat.randomForest will be used ( [33m default [39m )
#> -> predicted values : numerical, min = 0.008528888 , mean = 0.3232699 , max = 0.9931723
#> -> residual function : difference between y and yhat ( [33m default [39m )
#> -> residuals : numerical, min = -0.8275507 , mean = 0.001170303 , max = 0.8897291
#> -> model_info : package randomForest , ver. 4.6.14 , task regression ( [33m default [39m )
#> [32m A new explainer has been created! [39m
passanger <- titanic[sample(nrow(titanic), 1) ,-9]
passanger
#> gender age class embarked country fare sibsp parch
#> 105 male 1 2nd Southampton India 39 2 1
Now we are ready for generating various explantions and then describing it with describe() function.
## Feature Importance
Feature importance explanation shows the importance of all the model’s variables. As it is a global explanation technique, no passanger need to be specified.
importance_rf <- feature_importance(explain_titanic_rf)
plot(importance_rf)
Function describe() easily describes which variables are the most important. Argument nonsignificance_treshold as always sets the level above which variables become significant. For higher treshold, less variables will be described as significant.
describe(importance_rf)
#> The number of important variables for Random Forest's prediction is 5 out of 8.
#> Variables gender, class, age have the highest importantance.
## Ceteris Paribus Profiles
Ceteris Paribus profiles shows how the model’s input changes with the change of a specified variable.
perturbed_variable <- "class"
cp_rf <- ceteris_paribus(explain_titanic_rf,
passanger,
variables = perturbed_variable)
plot(cp_rf, variable_type = "categorical")
For a user with no experience, interpreting the above plot may be not straightforward. Thus we generate a natural language description in order to make it easier.
describe(cp_rf)
#> For the selected instance, prediction estimated by Random Forest is equal to 0.844.
#>
#> Model's prediction would decrease substantially if the value of class variable would change to "restaurant staff", "3rd", "engineering crew", "victualling crew", "deck crew", "1st".
#> The largest change would be marked if class variable would change to "restaurant staff".
#>
#> All the variables were displayed.
Natural lannguage descriptions should be flexible in order to provide the desired level of complexity and specificity. Thus various parameters can modify the description being generated.
describe(cp_rf,
display_numbers = TRUE,
label = "the probability that the passanger will survive")
#> Random Forest predicts that for the selected instance, the probability that the passanger will survive is equal to 0.844
#>
#> The most important change in Random Forest's prediction would occur for class = "restaurant staff". It decreases the prediction by 0.316.
#> The second most important change in the prediction would occur for class = "3rd". It decreases the prediction by 0.315.
#> The third most important change in the prediction would occur for class = "engineering crew". It decreases the prediction by 0.311.
#>
#> Other variable values are with less importance. They do not change the the probability that the passanger will survive by more than 0.3.
Please note, that describe() can handle only one variable at a time, so it is recommended to specify, which variables should be described.
describe(cp_rf,
display_numbers = TRUE,
label = "the probability that the passanger will survive",
variables = perturbed_variable)
#> Random Forest predicts that for the selected instance, the probability that the passanger will survive is equal to 0.844
#>
#> The most important change in Random Forest's prediction would occur for class = "restaurant staff". It decreases the prediction by 0.316.
#> The second most important change in the prediction would occur for class = "3rd". It decreases the prediction by 0.315.
#> The third most important change in the prediction would occur for class = "engineering crew". It decreases the prediction by 0.311.
#>
#> Other variable values are with less importance. They do not change the the probability that the passanger will survive by more than 0.3.
Continuous variables are described as well.
perturbed_variable_continuous <- "age"
cp_rf <- ceteris_paribus(explain_titanic_rf,
passanger)
plot(cp_rf, variables = perturbed_variable_continuous)
describe(cp_rf, variables = perturbed_variable_continuous)
#> Random Forest predicts that for the selected instance, prediction is equal to 0.844
#>
#> The highest prediction occurs for (age = 2), while the lowest for (age = 74).
#> Breakpoint is identified at (age = 9).
#>
#> Average model responses are *lower* for variable values *higher* than breakpoint (= 9).
Ceteris Paribus profiles are described only for a single observation. If we want to access the influence of more than one observation, we need to describe dependency profiles.
## Partial Dependency Profiles
pdp <- aggregate_profiles(cp_rf, type = "partial")
plot(pdp, variables = "fare")
describe(pdp, variables = "fare")
#> Random Forest's mean prediction is equal to 0.844.
#>
#> The highest prediction occurs for (fare = 35.1), while the lowest for (fare = 0).
#> Breakpoint is identified at (fare = 30.1).
#>
#> Average model responses are *higher* for variable values *higher* than breakpoint (= 30.1).
pdp <- aggregate_profiles(cp_rf, type = "partial", variable_type = "categorical")
plot(pdp, variables = perturbed_variable)
describe(pdp, variables = perturbed_variable)
#> Random Forest's mean prediction is equal to 0.844.
#>
#> Model's prediction would increase substantially if the value of class variable would change to "restaurant staff".
#> The largest change would be marked if class variable would change to "2nd".
#>
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http://en.wikisource.org/wiki/The_American_Practical_Navigator/Chapter_11 | # The American Practical Navigator/Chapter 11
The American Practical Navigator by the United States government Chapter 11
Chapters: 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, Glossary, Acronyms
## INTRODUCTION
### 1100. Development
The idea that led to development of the satellite navigation systems dates back to 1957 and the first launch of an artificial satellite into orbit, Russia’s Sputnik I. Dr. William H. Guier and Dr. George C. Wieffenbach at the Applied Physics Laboratory of the Johns Hopkins University were monitoring the famous “beeps” transmitted by the passing satellite. They plotted the received signals at precise intervals, and noticed that a characteristic Doppler curve emerged. Since satellites generally follow fixed orbits, they reasoned that this curve could be used to describe the satellite’s orbit. They then demonstrated that they could determine all of the orbital parameters for a passing satellite by Doppler observation of a single pass from a single fixed station. The Doppler shift apparent while receiving a transmission from a passing satellite proved to be an effective measuring device for establishing the satellite orbit.
Dr. Frank T. McClure, also of the Applied Physics Laboratory, reasoned in reverse: If the satellite orbit was known, Doppler shift measurements could be used to determine one’s position on Earth. His studies in support of this hypothesis earned him the first National Aeronautics and Space Administration award for important contributions to space development.
In 1958, the Applied Physics Laboratory proposed exploring the possibility of an operational satellite Doppler navigation system. The Chief of Naval Operations then set forth requirements for such a system. The first successful launching of a prototype system satellite in April 1960 demonstrated the Doppler system’s operational feasibility.
The Navy Navigation Satellite System (NAVSAT, also known as TRANSIT) was the first operational satellite navigation system. The system’s accuracy was better than 0.1 nautical mile anywhere in the world, though its availability was somewhat limited. It was used primarily for the navigation of surface ships and submarines, but it also had some applications in air navigation. It was also used in hydrographic surveying and geodetic position determination.
The transit launch program ended in 1988 and the system was disestablished when the Global Positioning System became operational in 1996.
## THE GLOBAL POSITIONING SYSTEM
### 1101. System Description
The Federal Radionavigation Plan has designated the NAVigation System using Timing And Ranging (NAVSTAR) Global Positioning System (GPS) as the primary navigation system of the U.S. government. GPS is a spaced-based radio positioning system which provides suitably equipped users with highly accurate position, velocity, and time data. It consists of three major segments: a space segment, a control segment, and a user segment.
The space segment comprises some 24 satellites. Spacing of the satellites in their orbits is arranged so that at least four satellites are in view to a user at any time, anywhere on the Earth. Each satellite transmits signals on two radio frequencies, superimposed on which are navigation and system data. Included in this data are predicted satellite ephemeris, atmospheric propagation correction data, satellite clock error information, and satellite health data. This segment normally consists of 21 operational satellites with three satellites orbiting as active spares. The satellites orbit at an altitude of 20,200 km, in six separate orbital planes, each plane inclined 55° relative to the equator. The satellites complete an orbit approximately once every 12 hours.
GPS satellites transmit pseudorandom noise (PRN) sequence-modulated radio frequencies, designated L1 (1575.42 MHz) and L2 (1227.60 MHz). The satellite transmits both a Coarse Acquisition Code (C/A code) and a Precision Code (P code). Both the P and C/A codes are transmitted on the L1 carrier; only the P code is transmitted on the L2 carrier. Superimposed on both the C/A and P codes is the navigation message. This message contains the satellite ephemeris data, atmospheric propagation correction data, and satellite clock bias.
GPS assigns a unique C/A code and a unique P code to each satellite. This practice, known as code division multiple access (CDMA), allows all satellites the use of a common carrier frequency while still allowing the receiver to determine which satellite is transmitting. CDMA also allows for easy user identification of each GPS satellite. Since each satellite broadcasts using its own unique C/A and P code combination, it can be assigned a unique PRN sequence number. This number is how a satellite is identified when the GPS control system communicates with users about a particular GPS satellite.
The control segment includes a master control station (MCS), a number of monitor stations, and ground antennas located throughout the world. The master control station, located in Colorado Springs, Colorado, consists of equipment and facilities required for satellite monitoring, telemetry, tracking, commanding, control, uploading, and navigation message generation. The monitor stations, located in Hawaii, Colorado Springs, Kwajalein, Diego Garcia, and Ascension Island, passively track the satellites, accumulating ranging data from the satellites’ signals and relaying them to the MCS. The MCS processes this information to determine satellite position and signal data accuracy, updates the navigation message of each satellite and relays this information to the ground antennas. The ground antennas then transmit this information to the satellites. The ground antennas, located at Ascension Island, Diego Garcia, and Kwajalein, are also used for transmitting and receiving satellite control information.
The user equipment is designed to receive and process signals from four or more orbiting satellites either simultaneously or sequentially. The processor in the receiver then converts these signals to navigation information. Since GPS is used in a wide variety of applications, from marine navigation to land surveying, these receivers can vary greatly in function and design.
### 1102. System Capabilities
GPS provides multiple users with accurate, continuous, worldwide, all-weather, common-grid, threedimensional positioning and navigation information.
To obtain a navigation solution of position (latitude, longitude, and altitude) and time (four unknowns), four satellites must be used. The GPS user measures pseudorange and pseudorange rate by synchronizing and tracking the navigation signal from each of the four selected satellites. Pseudorange is the true distance between the satellite and the user plus an offset due to the user’s clock bias. Pseudorange rate is the true slant range rate plus an offset due to the frequency error of the user’s clock. By decoding the ephemeris data and system timing information on each satellite’s signal, the user’s receiver/processor can convert the pseudorange and pseudorange rate to three-dimensional position and velocity. Four measurements are necessary to solve for the three unknown components of position (or velocity) and the unknown user time (or frequency) bias.
The navigation accuracy that can be achieved by any user depends primarily on the variability of the errors in making pseudorange measurements, the instantaneous geometry of the satellites as seen from the user’s location on Earth, and the presence of Selective Availability(SA). Selective Availability is discussed further below.
### 1103. Global Positioning System Concepts
GPS measures distances between satellites in orbit and a receiver on Earth, and computes spheres of position from those distances. The intersections of those spheres of position then determine the receiver’s position.
The distance measurements described above are done by comparing timing signals generated simultaneously by the satellites’ and receiver’s internal clocks. These signals, characterized by a special wave form known as the pseudo-random code, are generated in phase with each other. The signal from the satellite arrives at the receiver following a time delay proportional to its distance traveled. This time delay is detected by the phase shift between the received pseudorandom code and the code generated by the receiver. Knowing the time required for the signal to reach the receiver from the satellite allows the receiver to calculate the distance from the satellite. The receiver, therefore, must be located on a sphere centered at the satellite with a radius equal to this distance measurement. The intersection of three spheres of position yields two possible points of receiver position. One of these points can be disregarded since it is hundreds of miles from the surface of the Earth. Theoretically, then, only three time measurements are required to obtain a fix from GPS.
In practice, however, a fourth measurement is required to obtain an accurate position from GPS. This is due to receiver clock error. Timing signals travel from the satellite to the receiver at the speed of light; even extremely slight timing errors between the clocks on the satellite and in the receiver will lead to tremendous range errors. The satellite’s atomic clock is accurate to 10-9 seconds; installing a clock that accurate on a receiver would make the receiver prohibitively expensive. Therefore, receiver clock accuracy is sacrificed, and an additional satellite timing measurement is made. The fix error caused by the inaccuracies in the receiver clock is reduced by simultaneously subtracting a constant timing error from four satellite timing measurements until a pinpoint fix is reached.
Assuming that the satellite clocks are perfectly synchronized and the receiver clock’s error is constant, the subtraction of that constant error from the resulting distance determinations will reduce the fix error until a “pinpoint” position is obtained. It is important to note here that the number of lines of position required to employ this technique is a function of the number of lines of position required to obtain a fix. GPS determines position in three dimensions; the presence of receiver clock error adds an additional unknown. Therefore, four timing measurements are required to solve for the resulting four unknowns.
### 1104. GPS Signal Coding
Two separate carrier frequencies carry the signal transmitted by a GPS satellite. The first carrier frequency (L1) transmits on 1575.42 MHz; the second (L2) transmits on 1227.60 MHz. The GPS signal consists of three separate messages: the P-code, transmitted on both L1 and L2; the C/A code, transmitted on L1 only; and a navigation data message. The P code and C/A code messages are divided into individual bits known as chips. The frequency at which bits are sent for each type of signal is known as the chipping rate. The chipping rate for the P-code is 10.23 MHz (10.23 × 106 bits per second); for the C/A code, 1.023 MHz (1.023 × 106 bits per second); and for the data message, 50 Hz (50 bits per second). The P and C/A codes phase modulate the carriers; the C/A code is transmitted at a phase angle of 90° from the P code. The periods of repetition for the C/A and P codes differ. The C/A code repeats once every millisecond; the P-code sequence repeats every seven days.
As stated above the GPS carrier frequencies are phase modulated. This is simply another way of saying that the digital “1’s” and “0’s” contained in the P and C/A codes are indicated along the carrier by a shift in the carrier phase. This is analogous to sending the same data along a carrier by varying its amplitude (amplitude modulation, or AM) or its frequency (frequency modulation, or FM). See Figure 1104a. In phase modulation, the frequency and the amplitude of the carrier are unchanged by the “information signal,” and the digital information is transmitted by shifting the carrier’s phase. The phase modulation employed by GPS is known as bi-phase shift keying (BPSK).
Figure 1104a. Digital data transmission with amplitude, frequency and phase modulation.
Figure 1104b. Modulation of the L1 and L2 carrier frequencies with the C/A and P code signals.
Due to this BPSK, the carrier frequency is “spread” about its center frequency by an amount equal to twice the “chipping rate” of the modulating signal. In the case of the P code, this spreading is equal to (2 × 10.23 MHz) = 20.46 MHz. For the C/A code, the spreading is equal to (2 × 1.023 MHz) = 2.046 MHz. See Figure 1104b. Note that the L1 carrier signal, modulated with both the P code and C/A code, is shaped differently from the L2 carrier, modulated with only the P code. This spreading of the carrier signal lowers the total signal strength below the thermal noise threshold present at the receiver. This effect is demonstrated in Figure 1104c. When the satellite signal is multiplied with the C/A and P codes generated by the receiver, the satellite signal will be collapsed into the original carrier frequency band. The signal power is then raised above the thermal noise level.
The navigation message is superimposed on both the P code and C/A code with a data rate of 50 bits per second (50 Hz.) The navigation message consists of 25 data frames, each frame consisting of 1500 bits. Each frame is divided into five subframes of 300 bits each. It will, therefore, take 30 seconds to receive one data frame and 12.5 minutes to receive all 25 frames. The navigation message contains GPS system time of transmission; a handover word (HOW), allowing the transition between tracking the C/A code to the P code; ephemeris and clock data for the satellite being tracked; and almanac data for the satellites in orbit. It also contains coefficients for ionospheric delay models used by C/A receivers and coefficients used to calculate Universal Coordinated Time (UTC).
### 1105. The Correlation Process
The correlation process compares the signal received from the satellites with the signal generated by the receiver by comparing the square wave function of the received signal with the square wave function generated by the receiver. The computer logic of the receiver recognizes the square wave signals as either a +1 or a 0 depending on whether the signal is “on” or “off.” The signals are processed and matched by using an autocorrelation function.
This process defines the necessity for a “pseudorandom code.” The code must be repeatable (i.e., nonrandom) because it is in comparing the two signals that the receiver makes its distance calculations. At the same time, the code must be random for the correlation process to work; the randomness of the signals must be such that the matching process excludes all possible combinations except the combination that occurs when the generated signal is shifted a distance proportional to the received signal’s time delay. These simultaneous requirements to be both repeatable (non-random) and random give rise to the description of “pseudo-random”; the signal has enough repeatability to enable the receiver to make the required measurement while simultaneously retaining enough randomness to ensure incorrect calculations are excluded.
### 1106. Precise Positioning Service and Standard Positioning Service
Two levels of navigational accuracy are provided by the GPS: the Precise Positioning Service (PPS) and the Standard Positioning Service (SPS). GPS was designed, first and foremost, by the U.S. Department of Defense as a United States military asset; its extremely accurate positioning capability is an asset access to which the U.S. military may need to limit during time of war to prevent use by enemies. Therefore, the PPS is available only to authorized users, mainly the U.S. military and authorized allies. SPS, on the other hand, is available worldwide to anyone possessing a GPS receiver. Therefore PPS provides a more accurate position than does SPS.
Two cryptographic methods are employed to deny PPS accuracy to civilian users: selective availability (SA) and anti-spoofing (A-S). SA operates by introducing controlled errors into both the C/A and P code signals. SA can be programmed to degrade the signals’ accuracy even further during time of war, denying a potential adversary the ability to use GPS to nominal SPS accuracy. SA introduces two errors into the satellite signal: (1) The epsilon error: an error in satellite ephemeris data in the navigation message; and (2) clock dither: error introduced in the satellite atomic clocks’ timing. The presence of SA is the largest source of error present in an SPS GPS position measurement. The status of SA, whether off or on, can be checked at the USCG’s NAVCEN Web site:
http://www.navcen.uscg.gov
Anti-spoofing is designed to negate any hostile imitation of GPS signals. The technique alters the P code into another code, designated the Y code. The C/A code remains unaffected. The U.S. employs this technique to the satellite signals at random times and without warning; therefore, civilian users are unaware when this P code transformation takes place. Since anti-spoofing is applied only to the P code, the C/A code is not protected and can be spoofed.
Only users employing the proper cryptographic devices can defeat both SA and anti-spoofing. Without these devices, the user will be subject to the accuracy degradation of SA and will be unable to track the Y code.
GPS PPS receivers can use either the P code or the C/A code, or both, in determining position. Maximum accuracy is obtained by using the P code on both L1 and L2. The difference in propagation delay is then used to calculate ionospheric corrections. The C/A code is normally used to acquire the satellite signal and determine the approximate P code phase. Then, the receiver locks on the P code for precise positioning (subject to SA if not cryptographically equipped). Some PPS receivers possess a clock accurate enough to track and lock on the P code signal without initially tracking the C/A code. Some PPS receivers can track only the C/A code and disregard the P code entirely. Since the C/A code is transmitted on only one frequency, the dual frequency ionosphere correction methodology is unavailable and an ionospheric modeling procedure is required to calculate the required corrections.
SPS receivers, as mentioned above, provide positions with a degraded accuracy. The A-S feature denies SPS users access to the P code when transformed to the Y code. Therefore, the SPS user cannot rely on access to the P code to measure propagation delays between L1 and L2 and compute ionospheric delay corrections. Consequently, the typical SPS receiver uses only the C/A code because it is unaffected by A-S. Since C/A is transmitted only on L1, the dual frequency method of calculating ionospheric corrections is unavailable; an ionospheric modeling technique must be used. This is less accurate than the dual frequency method; this degradation in accuracy is accounted for in the 100-meter accuracy calculation. Figure 1106 presents the effect on SA and A-S on different types of GPS measurements.
SA/A-S Configuration SIS Interface Conditions PPS Users SPS Users SA Set to Zero A-S Off P-Code, no errors C/A-Code, no errors Full accuracy, spoofable Full accuracy,* spoofable SA at Non-Zero Value A-S Off P-Code, errors C/A-Code, errors Full accuracy, spoofable Limited accuracy, spoofable SA Set to Zero A-S On Y-Code, no errors C/A-Code, no errors Full accuracy, Not spoofable** Full accuracy,*** spoofable SA at Non-Zero Value A-S On Y-Code, errors C/A-Code, errors Full accuracy, Not spoofable** Limited accuracy, spoofable * “Full accuracy” defined as equivalent to a PPS-capable UE operated in a similar manner. ** Certain PPS-capable UE do not have P- or Y-code tracking abilities and remain spoofable despite A-S protection being applied. *** Assuming negligible accuracy degradation due to C/A-code operation (but more susceptible to jamming).
Figure 1106. Effect of SA and A-S on GPS accuracy.
In order for the GPS receiver to navigate, it has to track satellite signals, make pseudorange measurements, and collect navigation data.
A typical satellite tracking sequence begins with the receiver determining which satellites are available for it to track. Satellite visibility is determined by user-entered predictions of position, velocity, and time, and by almanac information stored internal to the receiver. If no stored almanac information exists, then the receiver must attempt to locate and lock onto the signal from any satellite in view. When the receiver is locked onto a satellite, it can demodulate the navigation message and read the almanac information about all the other satellites in the constellation. A carrier tracking loop tracks the carrier frequency while a code tracking loop tracks the C/A and P code signals. The two tracking loops operate together in an iterative process to acquire and track satellite signals.
The receiver’s carrier tracking loop will locally generate an L1 carrier frequency which differs from the satellite produced L1 frequency due to a Doppler shift in the received frequency. This Doppler offset is proportional to the relative velocity along the line of sight between the satellite and the receiver, subject to a receiver frequency bias. The carrier tracking loop adjusts the frequency of the receiver-generated frequency until it matches the incoming frequency. This determines the relative velocity between the satellite and the receiver. The GPS receiver uses this relative velocity to calculate the velocity of the receiver. This velocity is then used to aid the code tracking loop.
The code tracking loop is used to make pseudorange measurements between the GPS receiver and the satellites. The receiver’s tracking loop will generate a replica of the targeted satellite’s C/A code with estimated ranging delay. In order to match the received signal with the internally generated replica, two things must be done: 1) The center frequency of the replica must be adjusted to be the same as the center frequency of the received signal; and 2) the phase of the replica code must be lined up with the phase of the received code. The center frequency of the replica is set by using the Doppler-estimated output of the carrier tracking loop. The receiver will then slew the code loop generated C/A code though a millisecond search window to correlate with the received C/A code and obtain C/A tracking.
Once the carrier tracking loop and the code tracking loop have locked onto the received signal and the C/A code has been stripped from the carrier, the navigation message is demodulated and read. This gives the receiver other information crucial to a pseudorange measurement. The navigation message also gives the receiver the handover word, the code that allows a GPS receiver to shift from C/A code tracking to P code tracking.
The handover word is required due to the long phase (seven days) of the P code signal. The C/A code repeats every millisecond, allowing for a relatively small search window. The seven day repeat period of the P code requires that the receiver be given the approximate P code phase to narrow its search window to a manageable time. The handover word provides this P code phase information. The handover word is repeated every subframe in a 30 bit long block of data in the navigation message. It is repeated in the second 30 second data block of each subframe. For some receivers, this handover word is unnecessary; they can acquire the P code directly. This normally requires the receiver to have a clock whose accuracy approaches that of an atomic clock. Since this greatly increases the cost of the receiver, most receivers for non-military marine use do not have this capability.
### 1108. User Range Errors and Geometric Dilution of Precision
There are two formal position accuracy requirements for GPS:
1) The PPS spherical position accuracy shall be 16 meters SEP (spherical error probable) or better.
2) The SPS user two dimensional position accuracy shall be 100 meters 2 drms or better.
Assume that a universal set of GPS pseudorange measurements results in a set of GPS position measurements. The accuracy of these measurements will conform to a normal (i.e. values symmetrically distributed around a mean of zero) probability function because the two most important factors affecting accuracy, the geometric dilution of precision (GDOP) and the user equivalent range error (UERE), are continuously variable.
The UERE is the error in the measurement of the pseudoranges from each satellite to the user. The UERE is the product of several factors, including the clock stability, the predictability of the satellite’s orbit, errors in the 50 Hz navigation message, the precision of the receiver’s correlation process, errors due to atmospheric distortion and the calculations to compensate for it, and the quality of the satellite’s signal. The UERE, therefore, is a random error which is the function of errors in both the satellites and the user’s receiver.
The GDOP depends on the geometry of the satellites in relation to the user’s receiver. It is independent of the quality of the broadcast signals and the user’s receiver. Generally speaking, the GDOP measures the “spread” of the satellites around the receiver. The optimum case would be to have one satellite directly overhead and the other three spaced 120° around the receiver on the horizon. The worst GDOP would occur if the satellites were spaced closely together or in a line overhead.
There are special types of DOP’s for each of the position and time solution dimensions; these particular DOP’s combine to determine the GDOP. For the vertical dimension, the vertical dilution of precision (VDOP) describes the effect of satellite geometry on altitude calculations. The horizontal dilution of precision (HDOP) describes satellite geometry’s effect on position (latitude and longitude) errors. These two DOP’s combine to determine the position dilution of precision (PDOP). The PDOP combined with the time dilution of precision (TDOP) results in the GDOP. See Figure 1108.
Figure 1108. Position and time error computations.
### 1109. Ionospheric Delay Errors
Article 1108 covered errors in GPS positions due to errors inherent in the satellite signal (UERE) and the geometry of the satellite constellation (GDOP). Another major cause of accuracy degradation is the effect of the ionosphere on the radio frequency signals that comprise the GPS signal.
A discussion of a model of the Earth’s atmosphere will be useful in understanding this concept. Consider the Earth as surrounded by three layers of atmosphere. The first layer, extending from the surface of the Earth to an altitude of approximately 10 km, is known as the troposphere. Above the troposphere and extending to an altitude of approximately 50 km is the stratosphere. Finally, above the stratosphere and extending to an altitude that varies as a function of the time of day is the ionosphere. Though radio signals are subjected to effects which degrade its accuracy in all three layers of this atmospheric model, the effects of the ionosphere are the most significant to GPS operation.
The ionosphere, as the name implies, is that region of the atmosphere which contains a large number of ionized molecules and a correspondingly high number of free electrons. These charged molecules have lost one or more electrons. No atom will loose an electron without an input of energy; the energy input that causes the ions to be formed in the ionosphere comes from the ultraviolet (U-V) radiation of the Sun. Therefore, the more intense the Sun’s rays, the larger the number of free electrons which will exist in this region of the atmosphere.
The largest effect that this ionospheric effect has on GPS accuracy is a phenomenon known as group time delay. As the name implies, group time delay results in a delay in the time a signal takes to travel through a given distance. Obviously, since GPS relies on extremely accurate timing measurement of these signals between satellites and ground receivers, this group time delay can have a noticeable effect on the magnitude of GPS position error.
The group time delay is a function of several elements. It is inversely proportional to the square of the frequency at which the satellite transmits, and it is directly proportional to the atmosphere’s total electron content (TEC), a measure of the degree of the atmosphere’s ionization. The general form of the equation describing the delay effect is:
$\Delta t = \frac { (K \times \text{TEC} ) } {f \, ^2}$
where
Δt = group time delay f = operating frequency K = constant
Since the Sun’s U-V radiation ionizes the molecules in the upper atmosphere, it stands to reason that the time delay value will be highest when the Sun is shining and lowest at night. Experimental evidence has borne this out, showing that the value for TEC is highest around 1500 local time and lowest around 0500 local time. Therefore, the magnitude of the accuracy degradation caused by this effect will be highest during daylight operations. In addition to these daily variations, the magnitude of this time delay error also varies with the seasons; it is highest at the vernal equinox. Finally, this effect shows a solar cycle dependence. The greater the number of sunspots, the higher the TEC value and the greater the group time delay effect. The solar cycle typically follows an eleven year pattern. The next solar cycle will be at a minimum in 2006 and peak again in 2010. Given that this ionospheric delay introduces a serious accuracy degradation into the system, how does GPS account for it? There are two methods used: (1) the dual frequency technique, and (2) the ionospheric delay method.
### 1110. Dual Frequency Correction Technique
As the term implies, the dual frequency technique requires the ability to acquire and track both the L1 and L2 frequency signals. Recall from the discussion in Article 1103 that the C/A and P codes are transmitted on carrier frequency L1, but only the P code is transmitted on L2. Recall also that only authorized operators with access to DOD cryptographic material are able to copy the P code. It follows, then, that only those authorized users are able to copy the L2 carrier frequency. Therefore, only those authorized users are able to use the dual frequency correction method. The dual frequency method measures the distance between the satellite and the user based on both the L1 and L2 carrier signal. These ranges will be different because the group time delay for each signal will be different. This is because of the frequency dependence of the time delay error. The range from the satellite to the user will be the true range combined with the range error caused by the time delay, as shown by the following equation:
R(f) = Ractual + error term
where R(f) is the range which differs from the actual range as a function of the carrier frequency. The dual frequency correction method takes two such range measurements, R(L1) and R(L2). Recall that the error term is a function of a constant divided by the square of the frequency. By combining the two range equations derived from the two frequency measurements, the constant term can be eliminated and one is left with an equation in which the true range is simply a function of the two carrier frequencies and the measured ranges R(L1) and R(L2). This method has two major advantages over the ionospheric model method. (1) It calculates corrections from real-time measured data; therefore, it is more accurate. (2) It alleviates the need to include ionospheric data on the navigation message. A significant portion of the data message is devoted to ionospheric correction data. If the receiver is dual frequency capable, then it does not need any of this data.
The vast majority of maritime users cannot copy dual frequency signals. For them, the ionospheric delay model provides the correction for the group time delay.
### 1111. The Ionospheric Delay Model
The ionospheric delay model mathematically models the diurnal ionospheric variation. The value for this time delay is determined from a cosinusoidal function into which coefficients representing the maximum value of the time delay (i.e., the amplitude of the cosine wave representing the delay function); the time of day; the period of the variation; and a minimum value of delay are introduced. This model is designed to be most accurate at the diurnal maximum. This is obviously a reasonable design consideration because it is at the time of day when the maximum diurnal time delay occurs that the largest magnitude of error appears. The coefficients for use in this delay model are transmitted to the receiver in the navigation data message. As stated in Article 1110, this method of correction is not as accurate as the dual frequency method; however, for the non-military user, it is the only method of correction available.
### 1112. Multipath Reflection Errors
Multipath reflection errors occur when the receiver detects parts of the same signal at two different times. The first reception is the direct path reception, the signal that is received directly from the satellite. The second reception is from a reflection of that same signal from the ground or any other reflective surface. The direct path signal arrives first, the reflected signal, having had to travel a longer distance to the receiver, arrives later. The GPS signal is designed to minimize this multipath error. The L1 and L2 frequencies used demonstrate a diffuse reflection pattern, lowering the signal strength of any reflection that arrives at the receiver. In addition, the receiver’s antenna can be designed to reject a signal that it recognizes as a reflection. In addition to the properties of the carrier frequencies, the high data frequency of both the P and C/A codes and their resulting good correlation properties minimize the effect of multipath propagation.
The design features mentioned above combine to reduce the maximum error expected from multipath propagation to less than 20 feet.
## DIFFERENTIAL GPS
### 1113. Differential GPS Concept
The discussions above make it clear that the Global Positioning System provides the most accurate positions available to navigators today. They should also make clear that the most accurate positioning information is available to only a small fraction of the using population: U.S. and allied military. For most open ocean navigation applications, the degraded accuracy inherent in selective availability and the inability to copy the precision code presents no serious hazard to navigation. A mariner seldom if ever needs greater than 100 meter accuracy in the middle of the ocean.
It is a different situation as the mariner approaches shore. Typically for harbor approaches and piloting, the mariner will shift to visual piloting. The increase in accuracy provided by this navigational method is required to ensure ship’s safety. The 100 meter accuracy of GPS in this situation is not sufficient. Any mariner who has groped his way through a restricted channel in a thick fog will certainly appreciate the fact that even a degraded GPS position is available for them to plot. However, 100 meter accuracy is not sufficient to ensure ship’s safety in most piloting situations. In this situation, the mariner needs P code accuracy. The problem then becomes how to obtain the accuracy of the Precise Positioning Service with due regard to the legitimate security concerns of the U.S. military. The answer to this seeming dilemma lies in the concept of Differential GPS (DGPS).
Differential GPS is a system in which a receiver at an accurately surveyed position utilizes GPS signals to calculate timing errors and then broadcasts a correction signal to account for these errors. This is an extremely powerful concept. The errors which contribute to GPS accuracy degradation, ionospheric time delay and selective availability, are experienced simultaneously by both the DGPS receiver and a relatively close user’s receiver. The extremely high altitude of the GPS satellites means that, as long as the DGPS receiver is within 100-200 km of the user’s receiver, the user’s receiver is close enough to take advantage of any DGPS correction signal.
The theory behind a DGPS system is straightforward. Located on an accurately surveyed site, the DGPS receiver already knows its location. It receives data which tell it where the satellite is. Knowing the two locations, it then calculates the theoretical time it should take for a satellite’s signal to reach it. It then compares the time that it actually takes for the signal to arrive. This difference in time between the theoretical and the actual is the basis for the DGPS receiver’s computation of a timing error signal; this difference in time is caused by all the errors to which the GPS signal is subjected; errors, except for receiver error and multipath error, to which both the DGPS and the user’s receivers are simultaneously subject. The DGPS system then broadcasts a timing correction signal, the effect of which is to correct for selective availability, ionospheric delay, and all the other error sources the two receivers share in common.
For suitably equipped users, DGPS results in positions at least as accurate as those obtainable by the Precise Positioning Service. This capability is not limited to simply displaying the correct position for the navigator to plot. The DGPS position can be used as the primary input to an electronic chart system, providing an electronic readout of position accurate enough to pilot safely in the most restricted channel.
## WAAS AND LAAS IN MARINE NAVIGATION
### 1114. WAAS/LAAS for Aeronautical Use
In 1994 the National Telecommunications and Information Administration (NTIA) produced a technical report for the Department of Transportation which concluded that the optimum mix of enhanced GPS systems for overall civilian use would consist of DGPS for marine and terrestrial use and a combined WAAS/LAAS system for air navigation.
The Wide Area Augmentation System (WAAS) concept is similar to the DGPS concept, except that correctional signals are sent from geostationary satellites via HF signals directly to the user’s GPS receiver. This eliminates the need for a separate receiver and antenna, as is the case with DGPS. WAAS is intended for enroute air navigation, with 25 reference stations widely spaced across the United States, for coverage of the entire U.S. and parts of Mexico and Canada.
The Local Area Augmentation System (LAAS) is intended for precision airport approaches, with reference stations located at airports and broadcasting their correction message on VHF radio frequencies.
While many marine GPS receivers incorporate WAAS circuitry (but not the more accurate, shorter-range LAAS), WAAS is not optimized for surface navigation because the HF radio signals are line-of-sight and are transmitted from geostationary satellites. At low angles to the horizon, the WAAS signal may be blocked and the resulting GPS position accuracy significantly degraded with no warning. The DGPS signal, on the other hand, is a terrain-following signal that is unaffected by objects in its path. It simply flows around them and continues on unblocked.
The accuracy of WAAS and DGPS is comparable, on the order of a few meters. WAAS was designed to provide 7 meter accuracy 95% of the time. DGPS was designed to provide 10 meter accuracy 95% of the time, but in actual use one can expect about 1-3 meter accuracy when the user is within 100 miles of he DGPS transmitter. Over 100 miles, DGPS accuracy will commonly degrade by an additional 1 meter per 100 miles from the transmitter site. Both systems have been found in actual use to provide accuracies somewhat better than designed.
The WAAS signal, while not certified for use in the marine environment as is DGPS, can be a very useful navigational tool if its limitations are understood. In open waters of the continental U.S., the WAAS signal can be expected to be available and useful, provided the receiver has WAAS circuitry and is programmed to use the WAAS data. Outside the U.S., or in any area where tall buildings, trees, or other obstructions rise above the horizon, the WAAS signal may be blocked, and the resulting GPS fix could be in error by many meters. Since the highest accuracy is necessary in the most confined waters, WAAS should be used with extreme caution in these areas.
WAAS can enhance the navigator’s situational awareness when available, but availability is not assured. Further, a marine receiver will provide no indication when WAAS data is not a part of the fix. [Aircraft GPS receivers may contain Receiver Autonomous Integrity Monitoring (RAIM) software, which does provide warning of WAAS satellite signal failure, and removes the affected signal from the fix solution.]
LAAS data, broadcast on VHF, is less subject to blocking, but is only available in selected areas near airports. Its range is about 30 miles. It is therefore not suitable for general marine navigational use.
### 1115. The Galileo System
Since the development of GPS, various European councils and commissions have expressed a need for a satellite navigation system independent of GPS. Economic studies have emphasized this need, and technological studies by the European Space Agency over several years have proven its feasibility. In early 2002 the European Union (EU) decided to fund the development of its new Galileo satellite navigation system. A great deal of preliminary scientific work has already been accomplished, which will enable the full deployment of Galileo over the next few years.
Several factors influenced the decision to develop Galileo, the primary one being that GPS is a U.S. military asset that can be degraded for civilian use on order of the U.S. Government (as is the Russian satellite navigation system GLONASS). Disruption of either system might leave European users without their primary navigation system at a critical time. In contrast, Galileo will be under civilian control and dedicated primarily to civilian use. It is important to note that since GPS has been operational, civilian uses are proliferating far more rapidly than anticipated, to the point that GPS planners are developing new frequencies and enhancements to GPS for civilian use (WAAS and LAAS), SA has been turned off (as of May 1, 2000), and the cost and size of receivers have plummeted.
Plans call for the Galileo constellation to consist of 30 satellites (27 usable and three spares) in three orbital planes, each inclined 56 degrees to the equator. The orbits are at an altitude of 23,616 km (about 12,750 nm). Galileo will be designed to serve higher latitudes than GPS, an additional factor in the EU decision, based on Scandinavian participation.
While U.S. GPS satellites are only launched one at a time, Galileo satellites are being designed with new miniaturization techniques that will allow several to be launched on the same rocket, a far more cost-efficient way to place them in orbit and maintain the constellation.
Galileo will also provide an important feature for civilian use that GPS does not: integrity monitoring. Currently, a civilian GPS user receives no indication that his unit is not receiving proper satellite signals, there being no provision for such notification in the code. However, Galileo will provide such a signal, alerting the user that the system is operating improperly.
The issue of compatibility with GPS is being addressed during ongoing development. Frequency sharing with GPS is under discussion, and it is reasonable to assume that a high degree of compatibility will exist when Galileo is operational. Manufacturers will undoubtedly offer a variety of systems which exploit the best technologies of both GPS and Galileo. Integration with existing shipboard electronic systems such as ECDIS and ECS will be ensured.
The benefit of Galileo for the navigator is that there will be two separate satellite navigation systems to rely on, providing not only redundancy, but also an increased degree of accuracy (for systems that can integrate both systems’ signals). Galileo should be first available in 2005, and the full constellation is scheduled to be up by 2008.
### 1116. GLONASS
The Global Navigation Satellite System (GLONASS), under the control of the Russian military, has been in use since 1993, and is based on the same principles as GPS. The space segment consists of 24 satellites in three orbital planes, the planes separated by 120 degrees and the individual satellites by 45 degrees. The orbits are inclined to the equator at an angle of 64.8 degrees, and the orbital period is about 11hours, 15minutes at an altitude of 19,100 km (10,313 nm). The designed system fix accuracy for civilian use is 100 meters horizontal (95%), 150 meters vertical, and 15 cm/sec. in velocity. Military codes provide accuracies of some 10-20 meters horizontal.
The ground segment of GLONASS lies entirely within the former Soviet Union. Reliability has been an ongoing problem for the GLONASS system, but new satellite designs with longer life spans are addressing these concerns. The user segment consists of various types of receivers that provide position, time, and velocity information.
GLONASS signals are in the L-band, operating in 25 channels with 0.5625 MHz separation in 2 bands: from 1602.5625 MHz to 1615.5 MHz, and from 1240 to 1260 MHz. | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 1, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.45369333028793335, "perplexity": 1469.1230643230128}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 5, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2014-42/segments/1413507443451.12/warc/CC-MAIN-20141017005723-00337-ip-10-16-133-185.ec2.internal.warc.gz"} |
http://mathhelpforum.com/calculus/65886-finding-eq-tangent-parabola.html | # Math Help - Finding eq of tangent to a parabola.
1. ## Finding eq of tangent to a parabola.
Find the equation of the tangent to a parabola $y^2=4ax$ at the given pt $(x_1,y_1)$ on it. What can you say about the tangent at $(0,0)$?
2. Originally Posted by varunnayudu
Find the equation of the tangent to a parabola $y^2=4ax$ at the given pt $(x_1,y_1)$ on it. What can you say about the tangent at $(0,0)$?
Just apply the definition for the first part:
$y - y_1 = \frac{dy}{dx}\bigg{|}_{x = x_1, y = y_1} (x - x_1)$
If $y_1 \neq 0, y - y_1 = \frac{2a}{y_1} (x - x_1)$
$y_1 y - y_1 ^2 = 2ax - 2ax_1$
If $y_1 = 0$, then $x_1 = 0$ and the tangent is the y - axis.
thanks man | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 11, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.7858551740646362, "perplexity": 369.59511061439844}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2015-40/segments/1443736673632.3/warc/CC-MAIN-20151001215753-00208-ip-10-137-6-227.ec2.internal.warc.gz"} |
https://crossminds.ai/video/sample-efficient-reinforcement-learning-of-undercomplete-pomdps-606febf0f43a7f2f827c1043/ | Sample-Efficient Reinforcement Learning of Undercomplete POMDPs
# Sample-Efficient Reinforcement Learning of Undercomplete POMDPs
Dec 06, 2020
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40 views
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###### Details
Partial observability is a common challenge in many reinforcement learning applications, which requires an agent to maintain memory, infer latent states, and integrate this past information into exploration. This challenge leads to a number of computational and statistical hardness results for learning general Partially Observable Markov Decision Processes (POMDPs). This work shows that these hardness barriers do not preclude efficient reinforcement learning for rich and interesting subclasses of POMDPs. In particular, we present a sample-efficient algorithm, OOM-UCB, for episodic finite undercomplete POMDPs, where the number of observations is larger than the number of latent states and where exploration is essential for learning, thus distinguishing our results from prior works. OOM-UCB achieves an optimal sample complexity of $O(1/\epsilon^2)$ for finding an $\epsilon$-optimal policy, along with being polynomial in all other relevant quantities. As an interesting special case, we also provide a computationally and statistically efficient algorithm for POMDPs with deterministic state transitions. Speakers: Chi Jin, Sham Kakade, Akshay Krishnamurthy, Qinghua Liu | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.8947429656982422, "perplexity": 1304.563616905819}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2021-25/segments/1623488517820.68/warc/CC-MAIN-20210622124548-20210622154548-00087.warc.gz"} |
http://mtapreviewer.com/2015/06/20/grade-6-mtap-reviewer-set-7-2/ | # Grade 6 MTAP Reviewer Set 8
1.) Which of the following numbers does not belong to the list:
12, 17, 22, 27, 32
2.) What should be subtracted from 3 to get 13/5?
3.) The sum of the digits of a 2-digit number is 13. When the digits are reversed, the new number is 27 less than the original number. What is the original number?
4.) The exterior of an open box is to be covered with gift wrapper. If the dimensions of the box are 5 by 8 by 12, and 5 is its height, what is the least gift wrap needed?
5.) The side lengths of the triangle are 4 cm, 4cm, and 5cm. Which angles are equal in measure?
6.) Find the next number in the list below.
2, 1, 4/5, 5/7,…
7.) A goat is tethered at the corner of a barn using a 3m rope. What is the area of the ground that the goat can graze?
8.) What is the lateral surface area of a cube whose side length is 8.05 cm?
9.) The diagonal of a rectangle is 13 cm. Which of the following is not its possible length?
a.) 5
b.) 6
c.) 12.5
d.) 14
10.) A certain bacteria double every day. If it started with 500 bacteria on the first day, how many bacteria will there be at the end of the 10th day?
11.) What is the sum of all integers from 1 up to 50?
12.) What is the largest 3-digit prime number?
Answers
1. 17, it’s a prime number
2. 2/5
3. 85
4. 368
5. A and C
6. 2/3 (reduced form of 6/9). Pattern is (n + 1)/(2n – 1)
7. $27 \pi/4$
8. 259.21 sq. cm.
9. 14, the side of a rectangle is always less than its diagonal
10. 256,000
11. 1275
12. 997 | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 1, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.5456758141517639, "perplexity": 701.5292666665603}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": false}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2017-47/segments/1510934806609.33/warc/CC-MAIN-20171122141600-20171122161600-00545.warc.gz"} |
https://mathoverflow.net/questions/45268/higher-composition-law | # Higher Composition Law
Prof M.Bhargava's work on "Higher Composition Law" which solved some outstanding conjectures on number theory seems to be very interesting topic. I have seen his papers but, in spite of the titles, it is not easy to understand (Of course in my point of view, for sure there are many people who can understand it easily).
Do you know any lecture note or expository paper which explains more details and some explicit example? especially his work on composition law for binary quadratic form.
Thanks
• Have you looked at his ICM notes or notes in this Algorithmic Number Theory Volume? His composition law for binary quadratic forms is of course the same as Gauss's. However, one new thing was a composition law on triples of binary quadratic forms. – Kimball Nov 8 '10 at 14:08
• @Franz: I think according to Theorem 1 of Bhargava's paper "Higher composition laws I" if $Q_{id,D}$ be any primitive binary quadratic form of discriminant $D$ such that there is a cube $A_0$ with $Q^{A0}_1= Q^{A0}_2=Q^{A0}_3=Q_{id,D}$ then there is a unique group law. For an specific $Q_{id,D}$ one can get usual Guass Composition Law. It seems that you have picked this specific case. I might be confused. – M.B Nov 9 '10 at 7:03 | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.8174988031387329, "perplexity": 422.6274405716338}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2019-18/segments/1555578527566.44/warc/CC-MAIN-20190419101239-20190419123239-00117.warc.gz"} |
https://oldschool.runescape.wiki/w/Prayers | # Prayer
(Redirected from Prayers)
This article has a calculator here.Calculators determine experience and costs based on real-time prices from the Grand Exchange Market Watch.
For a list of all requirements and unlockables within the Prayer skill, see Prayer/Level up table.
Prayer is a non-members combat skill. Prayer is trained by burying bones, using them on an altar in a player-owned house, by using them on the altar in the Chaos Temple (hut), by praying at the Ectofuntus with bonemeal and buckets of slime, or by killing reanimated monsters summoned via the Arceuus spellbook. Different bones give different amounts of experience.
Prayers are unlocked as the level in the skill goes up, which are used to aid the player in combat. The prayers can help with Attack, Defence, Strength, Ranged, Magic, and Hitpoints, among other uses. When prayers are activated, they drain the player's prayer points until the prayer is turned off or all prayer points are used.
Most prayers can be activated immediately before the attack hits and promptly deactivated in order to gain buffs and/or protection with minimal to no expenditure of prayer points. This is called prayer flicking.
Prayer level up - normal
The music that plays when levelling up.
Prayer level up - with unlocks
The music that plays when levelling up and unlocking new content.
## Recharging points
The Prayer interface.
The player can recharge all of their prayer points to full by praying at an altar, which are most often found in churches.
Praying at these altars will recharge the player's prayer points above the maximum:
In addition, consuming prayer potions, super restores, sanfew serums, Ancient brews and Zamorak brews will recharge prayer points proportional to the player's Prayer level, and consuming jangerberries restores 1 prayer point each. The Falador shield will also recharge a certain percentage of prayer points once or twice daily depending upon the tier of the shield.
The special attacks of these weapons will also restore prayer points: ancient mace, eldritch nightmare staff, Saradomin godsword.
The Catacombs of Kourend also have a special effect, where burying bones will restore a few prayer points based on the type of bone.
## Quick prayers
The quick-prayers interface.
On 6 February 2014, data orbs were added and has given the Prayer icon the ability to select your quick prayers. It can be left-clicked to activate, or deactivate, a group of prayers preselected by the player simultaneously. You can select which prayers are activated by right-clicking the button and choosing the "Setup quick-prayers" option. Before the addition of this function, players had to, sometimes frantically, locate the prayer tab and activate them one by one. This function allows players to place many of the most useful prayers on immediate standby. It is very useful for prayer flicking. Quick prayers can also be used as an easy way to turn off all prayers by double left-clicking it (to turn quick prayers on, then off).
## Prayers
The prayer tab contains all of the available prayers. To activate a prayer, simply click it. This will show a whitish circle around each active prayer, and will start to drain prayer points.
All prayers up to Mystic Might are available for free-to-play players, but prayers from Retribution onward require the player to be on a members' server. Additionally, Chivalry and Piety require completion of Camelot Training Room, and Preserve, Rigour, and Augury must be unlocked through prayer scrolls from Chambers of Xeric.
Level Prayer Effect Drain Rate Drain Effect[1] Members
1 Thick Skin +5% Defence 1 point per 12 seconds 3
4 Burst of Strength +5% Strength 1 point per 12 seconds 3
7 Clarity of Thought +5% Attack 1 point per 12 seconds 3
8 Sharp Eye +5% Ranged 1 point per 12 seconds 3
9 Mystic Will +5% Magical attack and defence 1 point per 12 seconds 3
10 Rock Skin +10% Defence 1 point per 6 seconds 6
13 Superhuman Strength +10% Strength 1 point per 6 seconds 6
16 Improved Reflexes +10% Attack 1 point per 6 seconds 6
19 Rapid Restore 2 x Restore rate for all skills except Hitpoints and Prayer 1 point per 36 seconds 1
22 Rapid Heal 2 x Restore rate for Hitpoints 1 point per 18 seconds 2
25 Protect Item Player keeps 1 extra item when they die (must be activated before death to occur) 1 point per 18 seconds 2
26 Hawk Eye +10% Ranged 1 point per 6 seconds 6
27 Mystic Lore +10% Magical attack and defence 1 point per 6 seconds 6
28 Steel Skin +15% Defence 1 point per 3 seconds 12
31 Ultimate Strength +15% Strength 1 point per 3 seconds 12
34 Incredible Reflexes +15% Attack 1 point per 3 seconds 12
37 Protect from Magic Protects against magic attacks 1 point per 3 seconds 12
40 Protect from Missiles Protects against ranged attacks 1 point per 3 seconds 12
43 Protect from Melee Protects against melee attacks 1 point per 3 seconds 12
44 Eagle Eye +15% Ranged 1 point per 3 seconds 12
45 Mystic Might +15% Magical attack and defence 1 point per 3 seconds 12
46 Retribution Deals damage up to 25% of your Prayer level to nearby targets upon the user's death 1 point per 12 seconds 3
49 Redemption Heals the player if they fall below 10% health 1 point per 6 seconds 6
52 Smite Removes 1 prayer point from an enemy for every 4 damage inflicted on the enemy 1 point per 2 seconds 18
55 Preserve Boosted stats last 50% longer 1 point per 18 seconds 2
60 Chivalry +15% Attack, +18% Strength, +20% Defence 1 point per 1.5 seconds 24
70 Piety +20% Attack, +23% Strength, +25% Defence 1 point per 1.5 seconds 24
74 Rigour +20% Ranged attack, +23% Ranged strength, +25% Defence 1 point per 1.5 seconds 24
77 Augury +25% Magical attack and defence, +25% Defence 1 point per 1.5 seconds 24
## Prayer drain
While active, each prayer slowly depletes a player's prayer points. Different prayers drain prayer points at different rates. For example, a low-level prayer such as Thick Skin drains prayer significantly slower than its higher level counterpart, Steel Skin.
Prayer bonus, determined by worn equipment allows a player to slow the rate at which prayer points are drained. Players can view their prayer bonus in the Equipment Stats window. Only certain types of armour, clothing, weapons, and jewellery grant a prayer bonus.
In practice, each point of prayer bonus effectively increases the duration prayer points will last by 3.33%. For example, if a player uses the "Protect from Melee" prayer with a prayer bonus of 0, their prayer points would drain at a rate of 1 point every 3 seconds. If that player then equips armour giving a prayer bonus of +15, the player can expect this duration to increase by 50%, draining 1 point per 4.5 seconds instead of 1 point every 3 seconds.
Prayer bonus does not help to stave off the side-effects of locations and monsters that drain Prayer.
### Prayer drain mechanics
Each prayer has an associated drain effect, and the total across all activated prayers is added to an internal prayer drain counter each game tick. Whenever this counter value exceeds a certain theshold, known as the player's prayer drain resistance, one prayer point is depleted, and that player's current prayer drain counter value decreases by their prayer drain resistance. As this can occur more than once per game tick, it is possible to lose more than one prayer point within a single game tick.[1]
Players have a base prayer drain resistance of 60, increased by 2 for every point of prayer bonus. In the example above, a player with a prayer bonus of +15 would have a prayer drain resistance of 90, instead of 60. This would result in prayer points taking an average of 50% longer to deplete. Prayer drain resistance can be calculated with the following formula:
${\displaystyle drain_{resistance}={2}\times {bonus}+60}$
The number of seconds it takes for one Prayer point to drain, requiring the summation of the drain effect of each Prayer as drain effect, is then calculated with the following formula:
${\displaystyle seconds=0.6*\left(drain_{resistance}/drain_{effect}\right)}$
## Prayer flicking
Flicking lets a player use prayers in combat without having their prayer points drain continuously. A skilled player will turn prayers on right before their effects are required, and turn them off immediately after. This will stop prayer from continuously draining between attacks. For prayer flicking involving protection prayers, the player will activate the prayer just before being hit, and turn it off immediately after the hit lands. This uses up very few prayer points, and negates prayer point usage completely if done quickly enough.
Although flicking requires timing and skill, doing it successfully can save prayer points and allow a player to fight monsters for much longer, or increase damage rates with offensive prayers. In some cases, flicking can take advantage of mechanics, such as rendering Dessous unable to attack the player. If done perfectly, no prayer will be consumed regardless of how long the fight lasts.
Most players will not have totally perfect timing. Wearing gear with a high prayer bonus will help you prayer flick much longer. Flicking is considerably easier when fighting a monster that matches your weapon's speed, and/or when playing with sounds on. A metronome set to 100 beats per minute (or once every 0.6 seconds) can be used for practicing.
The disadvantages to prayer flicking are the high click intensity associated with constantly turning prayers on and off, and the time needed to get good and consistent at it. If used in a high risk situation, incorrectly flicking may backfire as it can cause players to not have prayers on at the right time.
### How to prayer flick
Flicking Protect from Melee against monsters with a very slow attack speed.
To prayer flick, one must activate and deactivate a prayer so it is active on the needed game tick. If flicking a combat prayer, this is the tick you attack. If flicking a protection prayer, this is the tick your enemy attacks (which is when their attack animation begins, not necessarily the tick in which you take damage). If flicking against monsters, it will help immensely to know the monster's attack speed.
Flicking offensively with a crossbow on the Rapid setting. Note that the XP drop and overhead prayer appear at the same time.
While it is possible to prayer flick against monsters that use Magic or Ranged attacks, it is best to practice against monsters that use melee at a 2.4 second (4 tick) interval while using a 4-tick weapon if you are learning how to flick for the first time. Practicing during Slayer tasks is a relatively safe and yet rewarding way to learn. Mutated Bloodvelds are an example of a good monster to practice at: they are not aggressive, their hits are accurate (meaning you will see easily when you make a mistake), and they are easy to reach.
In essence, when using protection prayers, activate the prayer just before the opponent's attack animation begins (for example, a ranger raising his bow and shooting the arrow, or a meleer swinging his sword). When using offensive prayers, activate the prayer just before your attack animation begins (and the experience drop shows up, if your hit is successful). To consume no prayer points, turn the prayer off within the next tick.
Note: Latency to the server is unavoidable, usually the ping at 20 to 150 milliseconds to the closest server. Keep this in mind when prayer flicking.
There are some exceptions to the rule of protection prayer having to be active on the first tick of the attack: for example, many of TzTok-Jad, The Nightmare and Verzik Vitur's attacks are calculated shortly after the start of their attack animation to allow the player to react to them switching between their attacks.
### 1-tick prayer flicking
Demonstration of 1-tick prayer, including activation and deactivation.
While this method is very click-intensive, it is possible to have your quick-prayers active at all times while not draining any prayer points. 1-tick prayer involves activating and deactivating your quick-prayers on every single game tick, and requires precise timing along with strict adherence to the click pattern. Notably, this is the only way to reliably protect yourself in a multi-combat zone filled with aggressive enemies without expending prayer points, and works against enemies that cannot be reliably prayer-flicked against due to varying attack speeds (such as cave horrors). In addition, it can reliably be used for both protection and offensive prayers, to nullify and deal more damage at the same time. When done correctly, your overhead prayer should be visible at all times, but you will not lose any prayer points.
The Preserve and Rapid Heal prayers provide no benefit when using this technique.
## Equipment that affects Prayer
Some equipment can bypass or disable overhead other players' protection prayers, as well as drain, restore or depend on Prayer.
Most of this equipment cannot bypass monster protection prayers, with the exception of Verac's set against the Kalphite Queen.
### Special attacks
Weapon Notes
Ancient mace The ancient mace's special attack ignores Protect from Melee when used against players and drains their Prayer by the amount of damage inflicted, while restoring the user's Prayer by the same amount. It can restore the user's Prayer above their base level.
Dragon scimitar The dragon scimitar's special attack is more accurate and will disable as well as prevent a player from using their overhead protection prayers if it is a successful hit, for 5 seconds.
Dragon sword The dragon sword's special attack hits the target with 25% increased accuracy and damage, and ignores Protect from Melee when used against players.
Abyssal bludgeon The abyssal bludgeon's special attack deals a hit with 0.5% extra damage for every prayer point the attacker is missing.
Bandos godsword The Bandos godsword's special attack increases damage dealt by 21% and doubles the accuracy, draining one of the target's Combat stats by the amount of damage dealt, until it reaches 0. If the stat drained reaches 0 before all of the damage could be accounted for, another stat will be drained by the amount remaining. Stats are drained in the following order: Defence, Strength, Prayer, Attack, Magic, Ranged.
Saradomin godsword The Saradomin godsword's special attack increases damage dealt by 10% and doubles the accuracy. If it is a successful hit, it restores the user's Hitpoints by 50% of the damage dealt (with a minimum of 10 Hitpoints) and Prayer by 25% of damage dealt (with a minimum of 5 prayer points).
Eldritch nightmare staff The Eldritch nightmare staff's special attack increases damage dealt and restores the caster's prayer points by 50% of the damage dealt. It can boost the caster's prayer points above their base level.
### Passive/set effects
Equipment Notes
Necklace of faith When the user is hit down to less than 20% of their maximum hitpoints (including being hit for 0), they will have their Prayer restored for 10% of their Prayer level, destroying the necklace in the process.
Dragonbone necklace After it is equipped, burying bones (either manually or through the Bonecrusher) will restore a certain number of Prayer points.
Sapphire bolts (e) The passive effect of enchanted sapphire bolts causes the target to lose prayer points calculated as 1/20th of the attacker's current Ranged stat, and the attacker gains about half of them.[2]
Sapphire dragon bolts (e)
Spectral spirit shield The passive effect of the spectral spirit shield reduces the effectiveness of all Prayer draining attacks by 50%. This effect does not work against other players.
Verac's set The set effect of Verac's has a 25% chance to ignore the target's Defence, armour and protection prayers.
### Spells
Spell Notes
Saradomin Strike On a successful hit in PvP, Saradomin Strike lowers opponent's prayer points by 1.
Corruption spells Cast on oneself. The player's next successful hit has a chance to inflict corruption on an enemy player. Corruption drains 6 prayer points over 18 seconds.
### Miscellaneous
Item Notes
Prayer book Right clicking the prayer book while wearing a Holy symbol allows the player to use prayer to heal poison at the cost of some prayer points.
Prayer cape Restores 1 prayer point when equipped or operated. Can be done once every 60 seconds.
## Monsters that use Prayer
Several monsters are able to make use of protection prayers.
Monster Prayers Notes
Kalphite Queen Her first form will use Protect from Magic and Missiles simultaneously, while her second form will use Protect from Melee. Her prayers are purely visual, and only indicate a higher defence bonus against a particular attack style.
Mother Mother protects against the last attack style that was used against him until the player extinguishes the Fire of Domination, at which point Mother only protects against Magic.
Demonic gorilla The gorilla will spawn protecting from a random style. After 50 or more damage has been taken, the gorilla will switch its protection prayer according to the style of the last damage it took.
Sigmund Only when fought during Another Slice of H.A.M.. He will first protect against whatever style the player attacks him with, then Missiles to counter Zanik; once the player uses the ancient mace special attack against him at this point, his Prayer will be drained and he can no longer use it
Crystalline Hunllef / Corrupted Hunllef The Hunllef will spawn protecting from a random style. Will change its protection prayer to protect against the sixth attack it receives that it is not protecting from.
Judge of Yama Fought during the A Kingdom Divided quest.
Xamphur Fought during the A Kingdom Divided quest.
Nex Nex uses ancient curses, which are Zarosian prayers, during her final phase.
## Temporary boosts
Main article: Temporary skill boost
Boost Level
increase[d 1]
Visibility Other info
Prayer cape +1 Visible Activating the cape's effect will increase the corresponding skill by 1.
Edgeville Monastery and Nature Grotto
altars
+2 Visible Monastery requires 31 Prayer, and is available to free players.
Altar of nature requires completion of Nature Spirit.
Spicy stew
(yellow spice)
±0-5 Visible Depending on type of stew, any skill can be boosted or reduced by 0 to 5 levels randomly.
God Wars Dungeon altars +0-11 Visible Gaining a boost requires a god item in correspondence to the aligned god, restoring +1 for every item worn
(e.g. 2 Armadyl items worn restores +2 extra prayer if praying at the Armadyl altar).
Eldritch nightmare staff +1-60 Visible Uses 55% of Special attack bar and restores Prayer equal to 50% of the damage dealt. Similar to the Ancient mace, this can boost Prayer above the base level.
Ancient mace +1-39 Visible Requires completion of Another Slice of H.A.M.
Uses 100% of Special attack bar and restores Prayer equal to the damage dealt.
This can fill your Prayer up to your Prayer level + the damage dealt. For maximum effect, it's advised to use the special attack on an Undead combat dummy in conjunction with a high strength bonus and Slayer helmet prior to entering combat.
1. Extra prayer points do not enable use of a higher level prayer and do not decay.
## Quests
### Quests requiring Prayer
Quest Prayer
requirement
Other skill requirements
Another Slice of H.A.M. 25 15
Scorpion Catcher 31 -
Legends' Quest 42 50 , 50 , 50 , 45 , 56 , 52 , 50 , 50 , 50
Enakhra's Lament 43 50 , 45 , 39
Rum Deal 47 50 , 42 , 40 , 42
The Great Brain Robbery 50 16 , 30
### Quests rewarding Prayer experience
Quest Experience
reward
Prayer
requirement
Other requirements
Rag and Bone Man I 500 - -
Making History 1,000 - -
Recruitment Drive 1,000 - 12
The Restless Ghost 1,125 - -
Priest in Peril 1,406 - -
Mountain Daughter 2,000 - 20
Ghosts Ahoy 2,400 - 25 , 20
Another Slice of H.A.M. 3,000 25 15
Rag and Bone Man II 5,000 - 40 , 20
The Great Brain Robbery 6,000 50 16 , 30
Rum Deal 7,000 47 42 , 50 , 40 , 42
Spirits of the Elid 8,000 - 37 , 33 , 37 , 37
Swan Song 10,000 - 100 , 66 , 62 , 62 , 45 , 42 , 40
Holy Grail 11,000 - 20
Total 59,431
### Skill choice
Upon completing any of the following quests, players may choose to allocate experience to Prayer. These rewards usually come in the form of items, such as lamps or books, and are independent of any experience rewards directly received for completing the quest.
QuestExperience
reward
Skills availableSkill requirements
X Marks the Spot300AnyNone
Client of Kourend500 twiceAnyNone
Fairytale II - Cure a Queen2,500Any skill above 30 49 , 57
A Tail of Two Cats2,500 twiceAny skill above 30None
The Great Brain Robbery5,000Any skill above 30 16 , 30 , 50
King's Ransom5,000Any skill above 50 65
Darkness of Hallowvale2,000 three timesAny skill above 30 5 , 20 , 22 , 32 , 33 , 40
A Taste of Hope2,500 three timesAny skill above 35 48 , 40 , 40 , 45 , 38
A Kingdom Divided10,000Any skill above 40 54 , 52 , 52 , 50 , 42 ,
38 , 35
Architectural Alliance
(miniquest)
10,000Any skill above 40None
In Search of Knowledge
(miniquest)
10,000Any skill above 40None
Curse of the Empty Lord
(miniquest)
10,000Any skill above 50Some players will need 31
One Small Favour10,000 twiceAny skill above 30 36 , 25 , 18 , 30
Recipe for Disaster
(The final battle)
20,000Any skill above 50 175 , 70 , 48 , 50 , 53 ,
53 , 25 , 59 , 40 , 50 ,
40 , 40 , 10 , 10 , 36
Legends' Quest7,650 four times
107 , 50 , 50 , 45 , 56 , 52 ,
42 , 50 , 50 , 50 , 50
Sins of the Father15,000 three timesAny skill above 60 62 , 60 , 56 , 52 , 50 , 50 , 49
Total187,900
### Other Prayer experience rewards
Source Experience
reward
Requirements
Information clerk 4000 151+ Kudos
Total 4,000
## Trivia
• A Prayer bonus of +30 is required to halve the drain rate of prayers.
• In RuneScape 2, the Prayer icon colour was originally yellow, but Jagex changed the colour on 21 November 2006 when Hunter was released.
• Within the game cache, there is an unused icon for Protect from Summoning (). This is left over from the original Old School RuneScape backup from August 2007 when the Summoning skill was still being developed[3].
## References
1. Jagex. Mod Ash's Twitter account. 29 December 2016. (Archived from the original on 30 May 2020.) Mod Ash: "The drain effect of the new Raids prayers is still subject to change. [1]"
2. Jagex. Mod Ash's Twitter account. 13 May 2016. (Archived from the original on 13 February 2021.) Mod Ash: "The target loses points calculated as 1/20 of the attacker's current Ranged stat, and the attacker gains about half of them."
3. Jagex. Mod Ash's Twitter account. 6 January 2017. (Archived from the original on 29 May 2020.) Mod Ash: "[Summoning] was in development in August 2007, and the icon was already in our repository. We've not deleted it." | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 2, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.22494029998779297, "perplexity": 7990.96062935696}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2022-05/segments/1642320304134.13/warc/CC-MAIN-20220123045449-20220123075449-00122.warc.gz"} |
https://mathematics.huji.ac.il/eventss/events-seminars?page=38 | 2017 Jul 26
# Logic seminar - Andrés Villaveces, "Around non-elementary dependence"
2:00pm to 4:00pm
## Location:
Ross 70
Dependent theories have now a very solid and well-established collection of results and applications. Beyond first order, the development of "dependency" has been rather scarce so far. In addition to the results due to Kaplan, Lavi and Shelah (dependent diagrams and the generic pair conjecture), I will speak on a few lines of current research around the extraction of indiscernibles for dependent diagrams and on various forms on dependence for abstract elementary classes. This is joint work with Saharon Shelah.
2018 Apr 11
# Logic Seminar - Shahar Oriel - "The infinite random simplicial complex"
11:00am to 1:00pm
## Location:
Ross 63
This talk will be a review of a paper by Andrew Brooke-Taylor and Damiano Testa
2017 Mar 01
# Logic seminar - Yair Hayut, "Weak Prediction Principles"
4:00pm to 6:00pm
## Location:
Ross 70
Weak Prediction Principles
Speaker: Yair Hayut
Abstract: Jensen's diamond is a well studied prediction principle. It holds in L (and other core models), and in many cases it follows from local instances of GCH.
In the talk I will address a weakening of diamond (due to Shaleh and Abraham) and present Abraham's theorem about the equivalence between weak diamond and a weak consequence of GCH. Abraham's argument works for successor cardinals. I will discuss what is known and what is open for inaccessible cardinals.
2017 Dec 13
# Logic seminar - Omer Mermelstein - "Template structures for the class of Hrushovski ab initio geometries"
11:00am to 1:00pm
## Location:
Math 209
Zilber's trichotomy conjecture, in modern formulation, distinguishes three flavours of geometries of strongly minimal sets --- disintegrated/trivial, modular, and the geometry of an ACF. Each of these three flavours has a classic template'' --- a set with no structure, a projective space over a prime field, and an algebraically closed field, respectively. The class of ab initio constructions with which Hrushovski refuted the conjecture features a new flavour of geometries --- non-modular, yet prohibiting any algebraic structure.
2018 May 09
# Logic Seminar - Immanuel Benporat - "Arbault sets"
11:00am to 1:00pm
## Location:
Ross 63
Arbault sets (briefly, A-sets) were first introduced by Jean Arbault in the context of Fourier analysis. One of his major results concerning these sets,asserts that the union of an A-set with a countable set is again an A-set. The next obvious step is to ask what happens if we replace the word "countable" by א_1. Apparently, an א_1 version of Arbault's theorem is independent of ZFC. The aim of this talk would be to give a proof (as detailed as possible) of this independence result. The main ingredients of the proof are infinite combinatorics and some very basic Fourier analysis.
2018 May 21
# Combinatorics: Daniel Kalmanovich and Or Raz (HU) "2 talks back-to-back"
11:00am to 12:30pm
## Location:
IIAS, Eilat hall, Feldman Building, Givat Ram
First speaker: Daniel kalmanovich, HU
Title: On the face numbers of cubical polytopes
Abstract:
Understanding the possible face numbers of polytopes, and of subfamilies of interest, is a fundamental question.
The celebrated g-theorem, conjectured by McMullen in 1971 and proved by Stanley (necessity) and by Billera and Lee (sufficiency) in 1980-81, characterizes the f-vectors of simplicial polytopes.
2018 Apr 09
# HD-Combinatorics Special Day: "Cohomology vanishing: from continuous to discrete", organized by Jozef Dodziuk
(All day)
## Location:
Room 130, IIAS, Feldman Building, Givat Ram
2018 Jun 05
# Tom Meyerovitch (BGU): On expansivness, topological dimension and mean dimesnion
2:15pm to 3:15pm
## Location:
Ross 70
Expansivness is a fundamental property of dynamical systems.
It is sometimes viewed as an indication to chaos.
However, expansiveness also sets limitations on the complexity of a system.
Ma\~{n}'{e} proved in the 1970’s that a compact metric space that
admits an expansive homeomorphism is finite dimensional.
In this talk we will discuss a recent extension of Ma\~{n}'{e}’s
theorem for actions generated by multiple homeomorphisms,
based on joint work with Masaki Tsukamoto. This extension relies on a
2018 Apr 10
2:15pm to 3:15pm
2018 Apr 24
2:00pm to 3:00pm
2018 May 01
2:00pm to 3:00pm
2018 Apr 16
# NT&AG: Linda Frey (University of Basel), "Explicit Small Height Bound for Q(E_tor)"
2:00pm to 3:00pm
## Location:
Room 70A, Ross Building, Jerusalem, Israel
2018 Apr 09
# Combinatorics: David Ellis (Queen Mary) "Random graphs with constant r-balls"
11:00am to 12:30pm
## Location:
IIAS, room 130, Feldman Building, Givat Ram
2018 May 10
# Colloquium: Zemer Kosloff (Hebrew University) - "Poisson point processes, suspensions and local diffeomprhisms of the real line"
2:30pm to 3:30pm
## Location:
Manchester Building (Hall 2), Hebrew University Jerusalem
The study of the representations theoretic properties of the group of diffeormorphisms of locally compact non compact Riemmanian manifolds which equal to the identity outside a compact set is is linked to a natural quasi invariant action of the group which moves all points of a Poisson point process according to the diffeomorphism (Gelfand-Graev-Vershik and Goldin et al.).
Neretin noticed that the local diffeomorphism group is a subgroup of a larger group which he called GMS and that GMS also acts in a similar manner on the Poisson point process.
2018 May 31
# Tamar Ziegler (Hebrew University) - "Concatenating cubic structure and polynomial patterns in primes"
2:30pm to 3:30pm
## Location:
Manchester Building (Hall 2), Hebrew University Jerusalem
A major difficulty in finding polynomial patterns in primes is the need to understand their distribution properties at short scales. We describe how for some polynomial configurations one can overcome this problem by concatenating short scale behavior in "many directions" to long scale behavior for which tools from additive combinatorics are available. | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 1, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.6697109341621399, "perplexity": 5333.475215604793}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.3, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2019-47/segments/1573496671245.92/warc/CC-MAIN-20191122065327-20191122093327-00283.warc.gz"} |
http://mathoverflow.net/questions/118333/smoothing-l1-norm-huber-vs-conjugate | # Smoothing L1 norm, Huber vs Conjugate
I'm trying to minimize a convex (not necessarily strictly convex) function involving an L1 norm (similar to lasso), which makes it non-differentiable at some points. So I'd like to smooth it and treat it as an L2 norm problem.
The two approaches I've seen ( http://www.ee.ucla.edu/~vandenbe/236C/lectures/smoothing.pdf ) are directly smoothing the L1 norm using the Huber function, and smoothing the conjugate (i.e, derive the dual norm, here it's L-infinity, which is still non-differentiable, then smooth that).
The Huber approach is much simpler, is there any advantage in the conjugate method over Huber? I can't see the point of smoothing the dual instead of just smoothing the primal.
-
Smoothing the dual will not give you a smooth primal. However, you get a strongly convex primal by dual smoothing (as opposed to merely a strictly convex primal by Huber smoothing). Hence, it depends on what kind of regularity you are aiming at: A smoother primal or a "more convex" primal - both can be helpful algorithmically. Moreover, note that there are numerous methods to treat nonsmooth convex minimization problems efficiently. – Dirk Jan 8 '13 at 7:15
@Dirk: why don't you write an answer about these? What you write here might interest more people. – András Bátkai Jan 8 '13 at 7:18
Following the suggestion of András Bátkai I post my comment as an answer:
Smoothing the dual or the primal problem are quite different things: Smoothing the dual will not give you a smooth primal. However, you get a strongly convex primal by dual smoothing (as opposed to merely a strictly convex primal by Huber smoothing). Hence, it depends on what kind of regularity you are aiming at: A smoother primal or a "more convex" primal - both can be helpful algorithmically. A smooth primal allows you to use gradients instead of subgradients and in turn allows you to apply gradient methods with appropriate stopping rules and such. A strongly convex primal leads to a proximal mapping of the primal objective which is not only non-expansive but contractive which is favorable for proximal-splitting methods.
Of course, you can also apply both primal and dual smoothing if you like.
Moreover, note that there are numerous methods to treat nonsmooth convex minimization problems efficiently
-
Great answer, thanks. One more clarification: are there any guarantees that minimizing the smoothed dual will actually produce good (optimal?) solutions to the original primal? – digdug Jan 8 '13 at 23:04
I don't think so - I even think that a dual solution does not always give you a way to infer a primal solution... (regardless of smoothing). Probably an answer can be found in Nesterov's "Smooth minimization of non-smooth problems". – Dirk Jan 9 '13 at 9:52
Smoothing the dual, we get a strongly convex primal. Then, is it true that the primal is smooth because the primal is strongly convex? – jakeoung Nov 17 '15 at 22:19
@jakeoung No, this is not true in general. – Dirk Nov 18 '15 at 5:25 | {"extraction_info": {"found_math": false, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.844231128692627, "perplexity": 355.360901424798}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2016-26/segments/1466783400031.51/warc/CC-MAIN-20160624155000-00142-ip-10-164-35-72.ec2.internal.warc.gz"} |
https://www.acmicpc.net/problem/11846 | 시간 제한 메모리 제한 제출 정답 맞은 사람 정답 비율
1 초 64 MB 15 10 10 66.667%
문제
Recently Yerzhan invented a new type of laser that is capable of measuring distance to distant objects. As any invention, laser needs testing and Yerzhan wants to test it on a moving animate creature (don't ask the final purpose of this laser). Since using mouses is too mainstream, Yerzhan went to the Forbidden Forest in search of a right creature.
The story of Yerzhan catching Gorlum is quite fascinating, but it would be inappropriate to tell it right now. What is more important is that he found the subject of his experiments. The creature's name is Gorlum and, despite Yerzhan's efforts, Gorlum, being a pretty dumb creature, only learned to strictly perform 5 types of commands, denoted by Latin symbols for convenience:
• "L" - Gorlum takes one step to its left - transition from point (x, y) to point (x − 1, y).
• "R" - Gorlum takes one step to its right - transition from point (x, y) to point (x + 1, y).
• "F" - Gorlum takes one step forward - transition from point (x, y) to point (x, y + 1).
• "B" - Gorlum takes one step backwards - transition from point (x, y) to point (x, y − 1).
• "I" - Gorlum takes a shiny ring with glowing texts out of his pocket and doesn't move at all.
For experiment purposes Yerzhan located his laser in point with coordinates (Laserx, Lasery) on a plane in Euclidean space. Yerzhan also taught Gorlum to understand and perform a list T of these 5 commands, where T is a string containing the commands in the order Gorlum must perform them. Gorlum starts at point (Gorlumx, Gorlumy).
Your task is to output the minimal and maximal distances to Gorlum detected by the laser. Your answer will be considered correct if the absolute or relative errors of the two numbers don't exceed 10−9.
입력
First two lines of input contain a natural number K ≤ 105 and a string S (|S| ≤ 104), consisting of symbols "LRFBI". To obtain the list of commands T, simply concatenate S K-times to itself (in other words T = SK).
The last two lines contain two pairs of numbers: coordinates of location of the laser (Laserx, Lasery) and of Gorlum (Gorlumx, Gorlumy).
All coordinates are integer numbers, not exceeding 104.
출력
Two real numbers - minimal and maximal detected distances. Absolute or relative errors of the numbers must not exceed 10−9.
예제 입력 1
100000
LRFBI
10000 10000
10000 10000
예제 출력 1
0.000000000000 1.000000000000 | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 1, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.36607789993286133, "perplexity": 3302.9918107177705}, "config": {"markdown_headings": false, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2021-17/segments/1618038072366.31/warc/CC-MAIN-20210413122252-20210413152252-00379.warc.gz"} |
https://meta.mathoverflow.net/questions/4516/what-to-do-with-links-to-arxiv-front-end | # What to do with links to arXiv front end?
There are quite a few posts which link to some paper at http://front.math.ucdavis.edu/ rather than directly at https://arxiv.org/ The front for arXiv at UC Davis seems to be down for some time. (I have noticed this on March 28.)
You can find some such posts using search for url:"*front.math.ucdavis.edu*". Or you can look at such posts which were recently bumped.
When there are dead links in posts, I'd consider useful to replace them with working link - at least if the post has been already bumped for some other reason. (For example, I guess there are many broken links to springerlink.)
However here the circumstances seem to be somewhat different:
• It seems plausible that front.math.ucdavis.edu will be operation again - in such cases no editing is needed.
• Even if the link is not working, it contains arXiv identifier - people who have at least some experience with arXiv will be able to deduce the arXiv link.
• And many people post not only link but also some other information (at least the authors and the title), which can help a lot in locating the paper.
Does somebody know what are the plans with front.math.ucdavis.edu - will it be working again in the future? And, depending on that, what is a reasonable course of action with posts which contain links to this domain.
• It is probably too soon to start worrying about such links. (I assume that this will start working again eventually - so far it wasn't down for a very long time.) But when I have checked what else can be edited in some posts that were recently bumped I noticed such links - so it seemed reasonable to ask about this. Apr 18 '20 at 7:58
• Would the 'feature-request' tag be useful here?
– YCor
Apr 19 '20 at 10:20
• @YCor Maybe if there's a new post requesting an automated replacement of the links. (Let us consider this one just as a question whether some action should be taken or not.) Apr 19 '20 at 11:03
• Posts where a link to front.math.ucdavis.edu or front.math.ucdavis.edu/search was removed/changed at some point. Apr 27 '20 at 7:13
• I have notice an edit in 2017 with the edit summary "corrected broken link (this arxiv's mirror is not in operation for several weeks)". So this is not the first time there is a similar problem. Apr 27 '20 at 7:14
• Does anyone know what happened to the front? I find it impossible to use the usual arXiv search engine, so I am very disturbed by its absence. Apr 28 '20 at 3:55
• The title is driving me crazy in the HNQ bar. Can we remove the extra "links to"? Apr 28 '20 at 5:01
• Sorry about that @LSpice. In fact, I didn't notice notice until you explicitly pointed it out. Apr 28 '20 at 5:02
• I recently updated mathoverflow.net/a/132018/16302. It contained four links starting with http://front.math.ucdavis.edu/ (and a search link, which I'll ignore here). For two of these, a simple search-and-replace works, using the replacement https://arxiv.org/abs/. But for the other two I needed to use https://arxiv.org/abs/math/ and remove a .5 from the final part of the url. I do not know why this is.
– jeq
Apr 30 '20 at 2:42 | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 1, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.5402972102165222, "perplexity": 830.0558536174706}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.3, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2021-43/segments/1634323585737.45/warc/CC-MAIN-20211023162040-20211023192040-00408.warc.gz"} |
https://en.wikipedia.org/wiki/Logarithmic_Schr%C3%B6dinger_equation | # Logarithmic Schrödinger equation
In theoretical physics, the logarithmic Schrödinger equation (sometimes abbreviated as LNSE or LogSE) is one of the nonlinear modifications of Schrödinger's equation. It is a classical wave equation with applications to extensions of quantum mechanics,[1] quantum optics,[2] nuclear physics,[3][4] transport and diffusion phenomena,[5][6] open quantum systems and information theory,[7][8][9][10][11][12] effective quantum gravity and physical vacuum models[13][14][15][16] and theory of superfluidity and Bose–Einstein condensation.[17] Its relativistic version (with D'Alembertian instead of Laplacian and first-order time derivative) was first proposed by G. Rosen.[18] It is an example of an integrable model.
## The equation
The logarithmic Schrödinger equation is the partial differential equation. In mathematics and mathematical physics one often uses its dimensionless form:
${\displaystyle i{\frac {\partial \psi }{\partial t}}+\Delta \psi +\psi \ln |\psi |^{2}=0.}$
for the complex-valued function ψ = ψ(x, t) of the particles position vector x = (x, y, z) at time t, and
${\displaystyle \Delta \psi ={\frac {\partial ^{2}\psi }{\partial x^{2}}}+{\frac {\partial ^{2}\psi }{\partial y^{2}}}+{\frac {\partial ^{2}\psi }{\partial z^{2}}}\,}$
is the Laplacian of ψ in Cartesian coordinates.
The relativistic version of this equation can be obtained by replacing the derivative operator with the D'Alembertian, similarly to the Klein–Gordon equation.
## References
1. ^ I. Bialynicki-Birula and J. Mycielski, Annals of Physics 100, 62 (1976); Commun. Math. Phys. 44, 129 (1975); Phys. Scripta 20, 539 (1979).
2. ^ H. Buljan, A. Šiber, M. Soljačić, T. Schwartz, M. Segev, and D. N. Christodoulides, Phys. Rev. E 68, 036607 (2003).
3. ^ E. F. Hefter, Phys. Rev. A 32, 1201 (1985).
4. ^ V. G. Kartavenko, K. A. Gridnev and W. Greiner, Int. J. Mod. Phys. E 7 (1998) 287.
5. ^ S. De Martino, M. Falanga, C. Godano and G. Lauro, Europhys. Lett. 63, 472 (2003); S. De Martino and G. Lauro, in: Proceed. 12th Conference on WASCOM, 2003.
6. ^ T. Hansson, D. Anderson, and M. Lisak, Phys. Rev. A 80, 033819 (2009).
7. ^ K. Yasue, Quantum mechanics of nonconservative systems, Annals of Physics 114 (1978) 479.
8. ^ N. A. Lemos, Phys. Lett. A 78 (1980) 239.
9. ^ J. D. Brasher, Nonlinear wave mechanics, information theory, and thermodynamics, Int. J. Theor. Phys. 30 (1991) 979.
10. ^ D. Schuch, Phys. Rev. A 55, 935 (1997).
11. ^ M. P. Davidson, Nuov. Cim. B 116 (2001) 1291.
12. ^ J. L. Lopez, Phys. Rev. E. 69 (2004) 026110.
13. ^ K. G. Zloshchastiev, Logarithmic nonlinearity in theories of quantum gravity: Origin of time and observational consequences, Grav. Cosmol. 16 (2010) 288–297 ArXiv:0906.4282.
14. ^ K. G. Zloshchastiev, Vacuum Cherenkov effect in logarithmic nonlinear quantum theory, Phys. Lett. A 375 (2011) 2305–2308 ArXiv:1003.0657.
15. ^ K. G. Zloshchastiev, Spontaneous symmetry breaking and mass generation as built-in phenomena in logarithmic nonlinear quantum theory, Acta Phys. Polon. B 42 (2011) 261–292 ArXiv:0912.4139.
16. ^ Scott, T.C.; Zhang, Xiangdong; Mann, Robert; Fee, G.J. (2016). "Canonical reduction for dilatonic gravity in 3 + 1 dimensions". Physical Review D. 93 (8): 084017. arXiv:. Bibcode:2016PhRvD..93h4017S. doi:10.1103/PhysRevD.93.084017.
17. ^ A. V. Avdeenkov and K.G. Zloshchastiev, Quantum Bose liquids with logarithmic nonlinearity: Self-sustainability and emergence of spatial extent, J. Phys. B: At. Mol. Opt. Phys. 44 (2011) 195303 ArXiv:1108.0847.
18. ^ G. Rosen, Phys. Rev. 183 (1969) 1186. | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 2, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.6756740212440491, "perplexity": 4529.749739212593}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2017-13/segments/1490218189198.71/warc/CC-MAIN-20170322212949-00450-ip-10-233-31-227.ec2.internal.warc.gz"} |
https://library.kiwix.org/3dprinting.stackexchange.com_en_all_2021-03/A/question/14892.html | ## OpenSCAD not rendering polyhedron
2
I'm trying to subtract a polyhedron from a cube, but it is not working (the cube remains solid). However, I can see the cut-out poly in preview mode (but not after a full render).
Preview -- poly cutout shows on the top (and bottom).
Rendered -- poly cutout not visible.
Poly Exploded -- pulled the poly to the right to show its shape.
Code
size = 30;
wall = 3;
wall_x2 = wall * 2;
nubGap = .125;
nubHeight = 8;
nubOffset = wall + nubGap;
xCutoutSize = size - wall_x2;
yCutoutSize = size - wall_x2;
cutoutLowerY = nubHeight + nubGap;
cutoutUpperOffset = nubOffset + wall;
difference() {
cube([size, size, size]);
translate([wall, wall, 0]) {
polyhedron(
points = [
[0, 0, -10],
[xCutoutSize, 0, -10],
[xCutoutSize, yCutoutSize, -10],
[0, yCutoutSize, -10],
[0, 0, cutoutLowerY],
[xCutoutSize, 0, cutoutLowerY],
[xCutoutSize, yCutoutSize, cutoutLowerY],
[0, yCutoutSize, cutoutLowerY],
[cutoutUpperOffset, cutoutUpperOffset, size],
[xCutoutSize - cutoutUpperOffset, cutoutUpperOffset, size],
[xCutoutSize - cutoutUpperOffset, yCutoutSize - cutoutUpperOffset, size],
[cutoutUpperOffset, yCutoutSize - cutoutUpperOffset, size]
],
faces = [
[0, 1, 2], [2, 3, 0], // bottom
[0, 1, 4], [1, 4, 5], // side A
[1, 2, 5], [2, 5, 6], // side B
[2, 3, 6], [3, 6, 7], // side C
[3, 0, 7], [0, 7, 4], // side D
[4, 5, 8], [5, 8, 9], // slope A
[5, 6, 9], [6, 9, 10], // slope B
[6, 7, 10], [7, 10, 11], // slope C
[7, 4, 11], [4, 11, 8], // slope D
[8, 9, 10], [10, 11, 8] // top
]
);
};
};
4
Usually when there's an overlap in two objects during a difference action, F6 render will resolve the problem. There's something more than that involved here, as reducing the height of the cube creates a non-manifold object from the difference. user R..'s answer has merit but is not going to solve the problem.
Isolating the cube from the code and exporting the result as an STL allows me to determine that the faces are generated in a manner preventing a proper difference action:
This image from meshmixer shows the faces have inverted normals. The order of the points are critical when describing a polyhedron. From the wiki page for OpenSCAD:
It is arbitrary which point you start with, but all faces must have points ordered in the same direction . OpenSCAD prefers clockwise when looking at each face from outside inward. The back is viewed from the back, the bottom from the bottom, etc. Another way to remember this ordering requirement is to use the right-hand rule. Using your right-hand, stick your thumb up and curl your fingers as if giving the thumbs-up sign, point your thumb into the face, and order the points in the direction your fingers curl.
EDIT: I reversed some of the points, haphazardly and luckily picked the correct ones:
faces = [
[0, 1, 2], [2, 3, 0], // bottom
[4, 1, 0], [1, 4, 5], // side A
[5, 2, 1], [2, 5, 6], // side B
[6, 3, 2], [3, 6, 7], // side C
[7, 0, 3], [0, 7, 4], // side D
[8, 5, 4], [5, 8, 9], // slope A
[9, 6, 5], [6, 9, 10], // slope B
[10, 7, 6], [7, 10, 11], // slope C
[11, 4, 7], [4, 11, 8], // slope D
[10, 9, 8], [8, 11, 10] // top
Ah, that makes sense, I'll give it a try. Thanks! – Josh M. – 2020-11-28T12:19:45.283
1Yes, OpenSCAD requires consistent normals, and from my experience actually requires (not just prefers) them pointing inwards if you want CSG functionality to all work right. – R.. GitHub STOP HELPING ICE – 2020-11-28T14:33:43.327
1I wasn't sure about the "requires versus prefers... pointing inwards" reference, but it's "prefers clockwise" according to the wiki. – fred_dot_u – 2020-11-28T15:59:55.777
Thanks. I had just reordered the points so they were clockwise but had a similar but different issue. I guess I don't understand why (for Side A) [4, 1, 0] works but [0, 4, 1] does not (as applied to all other faces) -- they are both clockwise looking at the face, but starting from the "top" is perhaps the difference? – Josh M. – 2020-11-28T16:16:31.163
2
If the polyhedron surface and top surface of the cube are exactly coplanar, which they seem to be, it won't work; OpenSCAD operates numerically rather than analytically and which is "inside" or "outside" the other is subject to numerical instability. Whenever using differences you need to make the object being subtracted extend by at least some small epsilon outside the surfact of the object you're subtracting from.
I did extend the bottom of the poly down through the bottom of the cube and got the same results. I'll try that again, though. – Josh M. – 2020-11-28T12:17:17.853 | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 1, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.3383939564228058, "perplexity": 2306.8559626867072}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.3, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2021-31/segments/1627046154796.71/warc/CC-MAIN-20210804045226-20210804075226-00379.warc.gz"} |
https://www.thejournal.club/c/paper/50665/ | $\mathcal C$-graph automatic groups
Murray Elder, Jennifer Taback
We generalize the notion of a graph automatic group introduced by Kharlampovich, Khoussainov and Miasnikov (arXiv:1107.3645) by replacing the regular languages in their definition with more powerful language classes. For a fixed language class $\mathcal C$, we call the resulting groups $\mathcal C$-graph automatic. We prove that the class of $\mathcal C$-graph automatic groups is closed under change of generating set, direct and free product for certain classes $\mathcal C$. We show that for quasi-realtime counter-graph automatic groups where normal forms have length that is linear in the geodesic length, there is an algorithm to compute normal forms (and therefore solve the word problem) in polynomial time. The class of quasi-realtime counter-graph automatic groups includes all Baumslag-Solitar groups, and the free group of countably infinite rank. Context-sensitive-graph automatic groups are shown to be a very large class, which encompasses, for example, groups with unsolvable conjugacy problem, the Grigorchuk group, and Thompson's groups $F,T$ and $V$.
arrow_drop_up | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.6753473281860352, "perplexity": 952.7030224224551}, "config": {"markdown_headings": false, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 20, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2021-25/segments/1623487600396.21/warc/CC-MAIN-20210613041713-20210613071713-00444.warc.gz"} |
https://thecleverprogrammer.com/2020/07/28/ridge-regression-in-machine-learning/ | Categories
# Ridge Regression in Machine Learning
The Ridge Regression is a regularized version of a Linear Regression. The Ridge Regression enables the machine learning algorithms to not only fit the data but also to keep weights of the model as small as possible.
It is quite familiar with the cost function that is used while training to be different from the performance measures that are used for testing. Apart from the Regularization, another reason for this difference is that a proper training data cost function should have optimization friendly derivatives. In contrast, the performance measures that are used for testing should be close as possible as the final objective.
Also, Read: Machine Translation Model using Neural Networks.
It is essential to scale the data by using Standard Scaler before using Ridge Regression, as it is sensitive to the scale of the input features. Now let’s go through the Ridge Regression algorithm to understand how to regularize a Liner Model using a Ridge algorithm.
## Data Preparation
We can use the Ridge algorithm either by computing a closed-form equation or by performing a Gradient Descent algorithm. Now to move further I will prepare the data using mathematical equations:
from sklearn.preprocessing import PolynomialFeatures
import numpy as np
np.random.seed(42)
m = 20
X = 3 * np.random.rand(m, 1)
y = 1 + 0.5 * X + np.random.randn(m, 1) / 1.5
X_new = np.linspace(0, 3, 100).reshape(100, 1)
## Ridge Regression Algorithm
Now here is how you can easily perform a Ridge Regression Algorithm using Scikit-Learn:
from sklearn.linear_model import Ridge
ridge_reg = Ridge(alpha=1, solver="cholesky", random_state=42)
ridge_reg.fit(X, y)
ridge_reg.predict([[1.5]])
ridge_reg = Ridge(alpha=1, solver="sag", random_state=42)
ridge_reg.fit(X, y)
ridge_reg.predict([[1.5]])
Now, let’s train and visualize the linear model using the ridge algorithm:
from sklearn.preprocessing import PolynomialFeatures
import matplotlib.pyplot as plt
from sklearn.linear_model import LinearRegression
from sklearn.pipeline import Pipeline
from sklearn.preprocessing import StandardScaler
def plot_model(model_class, polynomial, alphas, **model_kargs):
for alpha, style in zip(alphas, ("b-", "g--", "r:")):
model = model_class(alpha, **model_kargs) if alpha > 0 else LinearRegression()
if polynomial:
model = Pipeline([
("poly_features", PolynomialFeatures(degree=10, include_bias=False)),
("std_scaler", StandardScaler()),
("regul_reg", model),
])
model.fit(X, y)
y_new_regul = model.predict(X_new)
lw = 2 if alpha > 0 else 1
plt.plot(X_new, y_new_regul, style, linewidth=lw, label=r"$\alpha = {}$".format(alpha))
plt.plot(X, y, "b.", linewidth=3)
plt.legend(loc="upper left", fontsize=15)
plt.xlabel("$x_1$", fontsize=18)
plt.axis([0, 3, 0, 4])
plt.figure(figsize=(8,4))
plt.subplot(121)
plot_model(Ridge, polynomial=False, alphas=(0, 10, 100), random_state=42)
plt.ylabel("$y$", rotation=0, fontsize=18)
plt.subplot(122)
plot_model(Ridge, polynomial=True, alphas=(0, 10**-5, 1), random_state=42)
plt.show()
Now let’s go through the output:
• On the left, plain Ridge models are used, leading to linear predictions. On the right, the data is first expanded using PolynomialFeatures(degree=10).
• It is scaled using a StandardScaler, and finally, the Ridge models are applied to the resulting features: this is Polynomial Regression with Ridge regularization.
• Note how increasing α leads to flatter (i.e., less extreme, more reasonable) predictions, thus reducing the model’s variance but increasing its bias.
I hope you liked this asticle, feel free to ask your valuable questions in the comments section below. You can also follow me on Medium to read more amazing articles. | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 0, "mathjax_asciimath": 1, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.6200916171073914, "perplexity": 3167.7669930971247}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.3, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2020-34/segments/1596439736057.87/warc/CC-MAIN-20200810145103-20200810175103-00271.warc.gz"} |
https://www.jarviswang.me/?p=1316 | # 嵌入式系统中linux内核insmod时出现Unable to handle kernel paging request at virtual address xxxx可能的原因
• 2020-03-05
• 137
• 0
• 2
CONFIG_JUMP_LABEL选项是打开的，编译模块所使用的kernel也需要打开，否则就会出现图中的crash。
CONFIG_JUMP_LABEL: │
│ │
│ This option enables a transparent branch optimization that │
│ makes certain almost-always-true or almost-always-false branch │
│ conditions even cheaper to execute within the kernel. │
│ │
│ Certain performance-sensitive kernel code, such as trace points, │
│ scheduler functionality, networking code and KVM have such │
│ branches and include support for this optimization technique. │
│ │
│ If it is detected that the compiler has support for "asm goto", │
│ the kernel will compile such branches with just a nop │
│ instruction. When the condition flag is toggled to true, the │
│ nop will be converted to a jump instruction to execute the │
│ conditional block of instructions. │
│ │
│ This technique lowers overhead and stress on the branch prediction │
│ of the processor and generally makes the kernel faster. The update │
│ of the condition is slower, but those are always very rare. │
│ │
│ ( On 32-bit x86, the necessary options added to the compiler │
│ flags may increase the size of the kernel slightly. ) │
│ │
│ Symbol: JUMP_LABEL [=y] │
│ Type : boolean │
│ Prompt: Optimize very unlikely/likely branches │
│ Location: │
│ -> General setup │
│ Defined at arch/Kconfig:49 │
│ Depends on: HAVE_ARCH_JUMP_LABEL [=y] | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 1, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.6655632257461548, "perplexity": 22778.264165769695}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2020-16/segments/1585370521574.59/warc/CC-MAIN-20200404073139-20200404103139-00283.warc.gz"} |
http://soft-matter.seas.harvard.edu/index.php?title=Experimental_observation_of_the_crystallization_of_hard_sphere_colloidal_particles_by_sedimentation_onto_flat_patterned_surfaces&diff=prev&oldid=6770 | # Difference between revisions of "Experimental observation of the crystallization of hard sphere colloidal particles by sedimentation onto flat patterned surfaces"
by Tom Kodger
## Reference
I.B. Ramsteiner, K.E. Jensen, D.A. Weitz, F. Spaepen. PRE 79, 011403 (2009);
## Keywords
Colloidal crystal, patterned substrate, bond order parameter, template
## Abstract
We present a confocal microscopy study of 1.55 μm monodisperse silica hard spheres as they sediment and crystallize at the bottom wall of a container. If the particles sediment onto a feature less flat wall, the two bottom layers crystallize simultaneously and layerwise growth follows. If the wall is replaced by a hexagonal template, only layerwise growth occurs. Our results complement earlier numerical simulations and experiments on other colloidal systems.
## Capillarity In Action
FIG. 1. Selected snapshots of the first three sedimented layers for four different area densities labels on top. Darker particles have higher-order parameters.
While this paper contains very little capillarity, except for basic sedimentation concepts, the paper contains several useful experimental approaches, such as a bond order parameter, that could be used in other capillarity analyses.
Briefly, the experiment system contains monodispersed silica spheres at low volume fraction in a fluorescent DMSO/water solution. Due to a density difference between the 2 components, these spheres slowly sediment according to,
$u_0=\frac{1}{18}\sigma^2\Delta\rho g/\eta \approx 4.7mm$ | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.765946626663208, "perplexity": 7556.08984235346}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.3, "absolute_threshold": 10, "end_threshold": 5, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2022-49/segments/1669446711121.31/warc/CC-MAIN-20221206225143-20221207015143-00689.warc.gz"} |
https://www.aimsciences.org/article/doi/10.3934/nhm.2019004 | # American Institute of Mathematical Sciences
March 2019, 14(1): 53-77. doi: 10.3934/nhm.2019004
## A network model of immigration: Enclave formation vs. cultural integration
1 Dept. of Biomathematics, UCLA, Los Angeles, CA 90095-1766, USA 2 Dept. of Mathematics, CSUN, Los Angeles, CA 91330-8313, USA 3 Dept. of Mathematics, UCLA, Los Angeles, CA 90095-1555, USA
* Corresponding author: Maria R. D'Orsogna
Received May 2018 Published January 2019
Fund Project: This work was made possible by support from grants ARO W1911NF-14-1-0472, ARO W1911NF-16-1-0165 (MRD), and NSF DMS-1516675 (TC).
Successfully integrating newcomers into native communities has become a key issue for policy makers, as the growing number of migrants has brought cultural diversity, new skills, but also, societal tensions to receiving countries. We develop an agent-based network model to study interacting "hosts" and "guests" and to identify the conditions under which cooperative/integrated or uncooperative/segregated societies arise. Players are assumed to seek socioeconomic prosperity through game theoretic rules that shift network links, and cultural acceptance through opinion dynamics. We find that the main predictor of integration under given initial conditions is the timescale associated with cultural adjustment relative to social link remodeling, for both guests and hosts. Fast cultural adjustment results in cooperation and the establishment of host-guest connections that are sustained over long times. Conversely, fast social link remodeling leads to the irreversible formation of isolated enclaves, as migrants and natives optimize their socioeconomic gains through in-group connections. We discuss how migrant population sizes and increasing socioeconomic rewards for host-guest interactions, through governmental incentives or by admitting migrants with highly desirable skills, may affect the overall immigrant experience.
Citation: Yao-Li Chuang, Tom Chou, Maria R. D'Orsogna. A network model of immigration: Enclave formation vs. cultural integration. Networks & Heterogeneous Media, 2019, 14 (1) : 53-77. doi: 10.3934/nhm.2019004
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. Initial conditions are randomly connected guest and host nodes with attitudes $x_{i, {\rm guest}}^{0} = -1$ and $x_{i, {\rm host}}^{0} = 1$. Other parameters are $N_{\rm h} = 900, N_{\rm g} = 100$, $\alpha = 3$, $A_{\rm in} = A_{\rm out} = 10$, $\sigma = 1$. The two panels differ only for $\kappa$, the attitude adjustment timescale, with $\kappa = 1000$ in panel (a) and $\kappa = 100$ in panel (b). (a) For slowly changing attitudes ($\kappa = 1000$), hostile attitudes persist over time, eventually leading to segregated clusters. (b) For fast changing attitudes ($\kappa = 100$), guests initially become more cooperative, as shown by the lighter red colors. Over time, a more connected host--guest cluster arises with hosts eventually adopting more cooperative attitudes as well">Figure 2. Simulated network dynamics leading to (a) complete segregation, and (b) integration between guest (red) and host (blue) populations. Shading of node colors represents the degree of hostility $|x_i^t|$ of node $i$ towards those of its opposite group, according to the color scheme shown in Fig. 1. Initial conditions are randomly connected guest and host nodes with attitudes $x_{i, {\rm guest}}^{0} = -1$ and $x_{i, {\rm host}}^{0} = 1$. Other parameters are $N_{\rm h} = 900, N_{\rm g} = 100$, $\alpha = 3$, $A_{\rm in} = A_{\rm out} = 10$, $\sigma = 1$. The two panels differ only for $\kappa$, the attitude adjustment timescale, with $\kappa = 1000$ in panel (a) and $\kappa = 100$ in panel (b). (a) For slowly changing attitudes ($\kappa = 1000$), hostile attitudes persist over time, eventually leading to segregated clusters. (b) For fast changing attitudes ($\kappa = 100$), guests initially become more cooperative, as shown by the lighter red colors. Over time, a more connected host--guest cluster arises with hosts eventually adopting more cooperative attitudes as well
Model diagram. Each node $i$ is characterized by a variable attitude $-1 \le x_i^t \le 1$ at time $t$. Negative values, depicted in red, indicate guest nodes; positive values represent hosts, colored in blue. The magnitude $\vert x_i^t \vert$ represents the degree of hostility of node $i$ towards members of the other group. Each node is shaded accordingly. All nodes $j, k$ linked to the central node $i$ represent the green-shaded social circle $\Omega_i^t$ of node $i$ at time $t$. The utility $U_i^t$ of node $i$ depends on its attitude relative to that of its $m^t_i$ connections in $\Omega_i^t$ and on $m^t_i$. Nodes maximize their utility by adjusting their attitudes $x_i^t$ and by establishing or severing connections, reshaping the network over time
Dynamics of the average utility per node $\langle U_i^t \rangle_{\rm guest}$ in panels (a) and (c), and of the average attitudes $\langle x^t_{i} \rangle_{\rm guest}, \langle x^t_{i} \rangle_{\rm host}$ in panels (b) and (d) for $N_{\rm g} = 200$ (a, b) and $N_{\rm g} = 20$ (c, d) guests in a total population of $N = 2000$ nodes. Parameters are $\alpha = 3$, $A_{\rm in} = A_{\rm out} = 10$, and $\sigma = 1$, and $\kappa = 100$ (faster) and $\kappa = 1000$ (slower) attitude adjustment. Initial attitudes are $x_{i, {\text{host}}}^0 = 1$ and $x_{i, {\rm {guest}}}^0 = -1$, with random connections between nodes so that on average each node is connected to $m_i^0 = 10$ others at $t = 0$, representing full insertion of guests into the community. Network remodeling (solid-red curve) and attitude adjustment (blue-dashed and green-dotted curves) are considered separately; their interplay is illustrated in full model simulations (purple-dot-dashed and magenta-double-dotted-dashed). Utility is increased in all cases, but attitude adjustment is more efficient at the onset due to the initially set cross-group connections. Network remodeling allows for higher utilities at longer times. For the full model, fast adjustment ($\kappa = 100$) leads to well integrated societies for $N_{\rm g} = 200$ as $t \to \infty$, given that $\langle x^t_{i} \rangle_{\rm host} \to 0^{+}$ and $\langle x^t_{i} \rangle_{\rm guest} \to 0^{-}$; for $N_{\rm g} = 20$ hosts and guests segregate, with guests adopting collaborative attitudes, $\langle x^t_{i} \rangle_{\rm host} \to 0.93$ and $\langle x^t_{i} \rangle_{\rm guest} \to 0^{-}$. Under slow adjustment ($\kappa = 1000$) hosts and guests will remain hostile and segregated with $\langle x^t_{i} \rangle_{\rm host} \to 0.95$, $\langle x^t_{i} \rangle_{\rm guest} \to -0.34$ for $N_{\rm g} = 200$ and $\langle x^t_{i} \rangle_{\rm host} \to 0.99, \langle x^t_{i} \rangle_{\rm guest} \to 0^-$ for $N_{\rm g} = 20$
. (a, b) Large migrant population $N_{\rm g} = 200$. Here, $I_{\rm int}^t \to 0$ and $v_{\rm out}^t \to 0$ at long times when only network remodeling is allowed, and nodes seek links with conspecifics. If only attitude adjustment is allowed, $I_{\rm int}^t$ remains fixed due to the quenched network connectivity, while $v_{\rm out}^t$ increases as guests and hosts adopt more cooperative attitudes. For the full model, slow attitude changes ($\kappa = 1000$) lead to segregation and $I_{\rm int}^t \to 0$, $v_{\rm int}^t \to 0$ as $t \to \infty$. Fast attitude changes ($\kappa = 100$) lead to non-zero values of $I_{\rm int}^t$ and $v_{\rm out}^t$, indicating a more cooperative society. (c, d) Small migrant population $N_{\rm g} = 20$. Results are similar to the previous case except for the full model where $I_{\rm int}^t \to 0$, $v_{\rm out}^t \to 0$ as $t \to \infty$ for both $\kappa = 1000$ and $\kappa = 100$. For low values of $N_{\rm g}$ segregation arises under both fast and slow attitude changes">Figure 4. Dynamics of the integration index $I^t_{\rm int}$ in panels (a) and (c) and of the out-group reward fraction $v^t_{\rm out}$ in panels (b) and (d). Parameters and initial conditions are the same as in Fig. 3. (a, b) Large migrant population $N_{\rm g} = 200$. Here, $I_{\rm int}^t \to 0$ and $v_{\rm out}^t \to 0$ at long times when only network remodeling is allowed, and nodes seek links with conspecifics. If only attitude adjustment is allowed, $I_{\rm int}^t$ remains fixed due to the quenched network connectivity, while $v_{\rm out}^t$ increases as guests and hosts adopt more cooperative attitudes. For the full model, slow attitude changes ($\kappa = 1000$) lead to segregation and $I_{\rm int}^t \to 0$, $v_{\rm int}^t \to 0$ as $t \to \infty$. Fast attitude changes ($\kappa = 100$) lead to non-zero values of $I_{\rm int}^t$ and $v_{\rm out}^t$, indicating a more cooperative society. (c, d) Small migrant population $N_{\rm g} = 20$. Results are similar to the previous case except for the full model where $I_{\rm int}^t \to 0$, $v_{\rm out}^t \to 0$ as $t \to \infty$ for both $\kappa = 1000$ and $\kappa = 100$. For low values of $N_{\rm g}$ segregation arises under both fast and slow attitude changes
, with initially cooperative hosts and uncooperative guests at $x_{i, {\rm host}}^0 = 0^+$ and $x_{i, {\rm guest}}^0 = -1$. (a) $I_{\rm int}^t$ decreases at the onset, eventually rising towards integration, where $I_{\rm int}^t \to 1$ as $t \to \infty$. The initial decrease is more pronounced for slow attitude adjustment ($\kappa = 1000$) and for larger guest populations ($N_{\rm g} = 200$) as described in the text. (b) $v_{\rm out}^t$ increases over long times as attitude adjustment allows for more cooperation between guests and hosts. Under slow attitude adjustment ($\kappa = 1000$) and large guest populations ($N_{\rm g} = 200$), $v_{\rm out}^t$ decreases at the onset, with players seeking in-group connections. As guests and hosts become more cooperative $v_{\rm out}^t$ increases">Figure 5. Dynamics of the integration index $I^t_{\rm out}$ in panel (a) and of the out-group reward fraction $v^t_{\rm out}$ in panel (b) for initially cooperative hosts. Parameters are the same as for the full model in Fig. 3, with initially cooperative hosts and uncooperative guests at $x_{i, {\rm host}}^0 = 0^+$ and $x_{i, {\rm guest}}^0 = -1$. (a) $I_{\rm int}^t$ decreases at the onset, eventually rising towards integration, where $I_{\rm int}^t \to 1$ as $t \to \infty$. The initial decrease is more pronounced for slow attitude adjustment ($\kappa = 1000$) and for larger guest populations ($N_{\rm g} = 200$) as described in the text. (b) $v_{\rm out}^t$ increases over long times as attitude adjustment allows for more cooperation between guests and hosts. Under slow attitude adjustment ($\kappa = 1000$) and large guest populations ($N_{\rm g} = 200$), $v_{\rm out}^t$ decreases at the onset, with players seeking in-group connections. As guests and hosts become more cooperative $v_{\rm out}^t$ increases
with initial hostile attitudes $x_{i, {\rm host}}^0 = 1$ and $x_{i, {\rm guest}}^0 = -1$. In the blue-solid curve $I_{\rm int}^0 = 0.91$; in the green-dashed curve $I_{\rm int}^0 = 0.37$; in the red-dotted curve $I_{\rm int}^0 = 0.06$. (a) For all three cases, $I_{\rm int}^t$ decreases from the initial values, but only the initially poorly connected case of $I_{\rm int}^0 = 0.06$ leads to full segregation, indicated by $I_{\rm int}^t \to 0$ as $t \to \infty$. For the other two cases, $I_{\rm int}^t \to 1$. (b) For all three cases $v_{\rm out}^t$ increases at the onset due to attitude adjustment, and later decreases due to network remodeling. Only $I_{\rm int}^0 = 0.06$ leads to long-time $v_{\rm out}^t \to 0$: as guest-host connections are severed, no socioeconomic utility can be shared. For the other two cases, $v_{\rm out}^t$ increases at long times, suggesting increasing rewards through cross-group connections">Figure 6. Dynamics of the integration index $I^t_{\rm out}$ in panel (a) and of the out-group reward fraction $v^t_{\rm out}$ in panel (b) under different initial random connectivities. Parameters are the same as in Fig 3 with initial hostile attitudes $x_{i, {\rm host}}^0 = 1$ and $x_{i, {\rm guest}}^0 = -1$. In the blue-solid curve $I_{\rm int}^0 = 0.91$; in the green-dashed curve $I_{\rm int}^0 = 0.37$; in the red-dotted curve $I_{\rm int}^0 = 0.06$. (a) For all three cases, $I_{\rm int}^t$ decreases from the initial values, but only the initially poorly connected case of $I_{\rm int}^0 = 0.06$ leads to full segregation, indicated by $I_{\rm int}^t \to 0$ as $t \to \infty$. For the other two cases, $I_{\rm int}^t \to 1$. (b) For all three cases $v_{\rm out}^t$ increases at the onset due to attitude adjustment, and later decreases due to network remodeling. Only $I_{\rm int}^0 = 0.06$ leads to long-time $v_{\rm out}^t \to 0$: as guest-host connections are severed, no socioeconomic utility can be shared. For the other two cases, $v_{\rm out}^t$ increases at long times, suggesting increasing rewards through cross-group connections
Integration index at steady state. In panel (a) $\langle I^*_{\rm int} \rangle$ is averaged over 20 realizations and plotted as a function of $A_{\rm out} / A_{\rm in}$ with $\kappa = \infty$. The bar indicates the variance. In panel (b) single representations $I^*_{\rm int}$ are shown as a function of $\kappa$ with $A_{\rm out} / A_{\rm in} = 2$. Other parameters are set at $\alpha = 3$ and $\sigma = 1$, with $N_{\rm h} = 1800$ and $N_{\rm g} = 200$. In both panels red solid circles represent initially unconnected, hostile hosts and guests, $x_{i, {\rm host}}^0 = 1$, $x_{i, {\rm guest}}^0 = -1$; blue triangles correspond to fully cooperative initial conditions $x_{i, {\rm host}}^0 = x_{i, {\rm guest}}^0 = 0$. When the ratio $A_{\rm out} / A_{\rm in}$ increases, the long-time state of the network changes from segregation to uniform mixture, and finally to reversed segregation. The transition for the default initial conditions occurs at larger $A_{\rm out} / A_{\rm in}$ ratios, compared to the cooperative initial conditions, as the former require higher compensation from out-group connections to overlook the hostile attitudes between guests and hosts. In panel (b) each data point corresponds to one realization. Increasing attitude adjustment time scale $\kappa$ leads to increased likelihood of segregation. A bimodal regime emerges for intermediate $\kappa$
Time $\tau_{\rm seg}$ to reach $\langle I_{\rm int}^*\rangle = 0.1$, where 90$\%$ of guest nodes are segregated as a function of (a) the sensitivity to the reward function $\sigma$, (b) the relative guest population $N_{\rm g}/N$ and (c) the total population $N$ assuming $N_{\rm g} = 0.1 N$. Other parameters are set to $\alpha = 3$, $A_{\rm in} = A_{\rm out} = 10$, $\kappa = 600$ in all panels. In panel (a) $N_{\rm g} = 200$, $N = 2000$; in panel (b) $\sigma = 1$ and $N = 2000$; in panel (c) $\sigma = 1$. In all three cases, guests and hosts are initially unconnected and hostile to each other, $x_{i, {\rm host}}^0 = 1$ and $x_{i, {\rm guest}}^0 = -1$. Each data point and its error bar represent the mean and the variance over $20$ simulations. In panel (a) increasing $\sigma$ allows for more tolerance to attitude differences, increasing the time to segregation. In panel (b) the higher guest population ratio leads to faster segregation as guests are more likely to establish in-group connections, forming guest only enclaves. In panel (c) the time to segregation increases with the overall population, for a constant $10\%$ guest population
Integration index at steady state. $\langle I^*_{\rm int} \rangle$ is averaged over 10 realizations and plotted as a function of $\kappa$ and $N_{\rm g} / N$ with $\alpha = 3$ in panel (a), and as a function of $\kappa$ and $\alpha$ with $N_{\rm g} / N = 0.1$ in panel (b). Other parameters are set at $A_{\rm in} = 10$, $A_{\rm out} = 20$, $\sigma = 1$, and $N = 2000$. In both panels guests and hosts are initially unconnected, with hostile attitudes, $x_{i, {\rm host}}^0 = 1$, $x_{i, {\rm guest}}^0 = -1$. In panel (a), for smaller $N_{\rm g} / N$, the transition from segregation to integration (or reverse segregation) occurs at larger $\kappa$. In panel (b) increasing $\alpha$ causes the transition point to shift towards larger $\kappa$
List of variables and parameters of the model
Symbol Description default values $x_i$ attitude -1 to 1 $A_{\rm in}$ maximal utility through in-group connection $10$ $A_{\rm out}$ maximal utility through out-group connection $1$ to $100$ $\sigma$ sensitivity to attitude difference $1$ $\kappa$ attitude adjustment timescale $100$ to $1000$ $\alpha$ cost of adding connections $3$ $N$ total population $2000$ $N_{\rm g}$ guest population $20$ to $200$ $N_{\rm h}$ host population $N - N_{\rm g}$
Symbol Description default values $x_i$ attitude -1 to 1 $A_{\rm in}$ maximal utility through in-group connection $10$ $A_{\rm out}$ maximal utility through out-group connection $1$ to $100$ $\sigma$ sensitivity to attitude difference $1$ $\kappa$ attitude adjustment timescale $100$ to $1000$ $\alpha$ cost of adding connections $3$ $N$ total population $2000$ $N_{\rm g}$ guest population $20$ to $200$ $N_{\rm h}$ host population $N - N_{\rm g}$
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http://mathhelpforum.com/algebra/102586-indices.html | 1. ## indices
hi need some assistance in figuring this out can u help me? Here's the question:
Given that {equ y= ax^b - 6} and that y=10 when x=2 and that y=48 when x=3 find the values of a and b.
i believe a simultaneous equation will form in order for me to figure out the values of a and b but i dont know how to form it...
2. Hi helloworld101
y= ax^b - 6
For x = 2 , y = 10 :
10 = a2^b - 6
a2^b = 16 .....................(1)
For x = 3 , y = 48 :
48 = a3^b - 6
a3^b = 54 .....................(2)
Divide the two equations
3. i dont understand can u elaborate more plz?
4. Hi helloworld101
You can try to divide equation (1) by equation (2) then write here what you've tried
5. ok i am not getting through with this sum plz explain more. i tried what u said but i not getting anything. ur help would be immensely appriciated...
6. $\frac{a \cdot 2^b = 16}{a \cdot 3^b = 54}$
$\frac{2^b}{3^b} = \frac{16}{54}$
continue ...
7. ## solution to problem
so this is what i got is the working correct along with the steps
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https://www.physicsforums.com/threads/forces-and-torque-on-a-block.305483/ | # Forces and Torque on a block
1. Apr 6, 2009
### littleman
1. The problem statement, all variables and given/known data
The drawing shows a rectangular piece of wood. The forces applied to corners B and D have the same magnitude and are directed parallel to the long and short sides of the rectangle. An axis of rotation is shown perpendicular to the plane of the rectangle at its center.
http://www.webassign.net/CJ/p9-73.gif
The magnitudes of the forces at corners B and D are each 17 N. The long side of the rectangle is 2.5 times as long as the short side. What are the magnitude and direction of the force FA applied to corner A? Assume that the direction of FA is the same as in part (b).
2. Relevant equations
Torque = Force * length
3. The attempt at a solution
So originally, I thought that to solve this problem, the torque at A would be equal in magnitude to the net torque from B and D. So I did the following:
let x = the length of the shorter side; therefore, 2.5x is the length of the longer side
let n = the force applied at A
n*x = 17x + 2.5*17*x
solving this, we can cancel out x, and get that n = 59.5; this is incorrect. I tried a few other things, including n*x + 17x = 2.5*17*x to get n=25.5, but that is also incorrect.
So I'm confused here, am I misreading the question? I know you guys can't solve the question for me, but maybe you can point me in the right direction...I can only submit the answer to this question one more time before webassign locks it out.
Thanks :)
2. Apr 6, 2009
### Dr.D
You did not say so, but I presume that this piece of wood is in equilibrium.
What is part (b)?
There is no force shown in the figure at A; are to understand that there is one at an angle?
Is there also a force applied at C?
3. Apr 6, 2009
### littleman
I am also assuming that the wood is in equilibrium, I posted all the information I was given that was pertinent to the question.
part b was just a multiple choice question, it asked what direction the force should be applied on A. The answer was in the direction to B.
There is no force on C, it never stated that there was and the diagram doesn't show it.
Similar Discussions: Forces and Torque on a block | {"extraction_info": {"found_math": false, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.8732010126113892, "perplexity": 388.67780827197214}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.3, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2017-34/segments/1502886105455.37/warc/CC-MAIN-20170819143637-20170819163637-00453.warc.gz"} |
http://link.springer.com/article/10.1007/s00245-015-9289-1 | Applied Mathematics & Optimization
, Volume 72, Issue 3, pp 523–547
# Homogenization of Functionals with Linear Growth in the Context of $$\mathcal A$$-quasiconvexity
Article
DOI: 10.1007/s00245-015-9289-1
Matias, J., Morandotti, M. & Santos, P.M. Appl Math Optim (2015) 72: 523. doi:10.1007/s00245-015-9289-1
## Abstract
This work deals with the homogenization of functionals with linear growth in the context of $$\mathcal A$$-quasiconvexity. A representation theorem is proved, where the new integrand function is obtained by solving a cell problem where the coupling between homogenization and the $$\mathcal A$$-free condition plays a crucial role. This result extends some previous work to the linear case, thus allowing for concentration effects.
### Keywords
$$\mathcal A$$-quasiconvexity Homogenization Representation of integral functionals Concentration effects
### Mathematics Subject Classification
Primary 35B27 Secondary 49J40 49K20 35E99 | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 1, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.9747976660728455, "perplexity": 1464.8118294265698}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2017-13/segments/1490218189884.21/warc/CC-MAIN-20170322212949-00594-ip-10-233-31-227.ec2.internal.warc.gz"} |
http://clipart.academickids.com/encyclopedia/index.php/Trigonometry | # Trigonometry
Trigonometry (from the Greek trigonon = three angles and metro = measure) is a branch of mathematics dealing with angles, triangles and trigonometric functions such as sine, cosine and tangent. It has some relationship to geometry, though there is disagreement on exactly what that relationship is; for some, trigonometry is just a subtopic of geometry.
# Early history
The origins of trigonometry trace to the cultures of the ancient Egyptians and Babylonians and Indus Valley civilizations, over 3000 years ago. Indian mathematicians were the pioneers of variable computations algebra for use in astronomical calculations along with trigonometry. Lagadha is the only known mathematician today to have used geometry and trigonometry for astronomy in his book Vedanga Jyotisha, much of whose works were destroyed by foreign invaders on India.
Greek mathematician Hipparchus circa 150 BC compiled a trigonometric table for solving triangles.
Another Greek mathematician, Ptolemy circa 100 AD further developed trigonometric calculations.
## Trigonometry today
There are an enormous number of applications of trigonometry. Of particular value is the technique of triangulation which is used in astronomy to measure the distance to nearby stars, in geography to measure distances between landmarks, and in satellite navigation systems. Other fields which make use of trigonometry include astronomy (and hence navigation, on the oceans, in aircraft, and in space), music theory, acoustics, optics, analysis of financial markets, electronics, probability theory, statistics, biology, medical imaging (CAT scans and ultrasound), pharmacy, chemistry, number theory (and hence cryptology), seismology, meteorology, oceanography, many physical sciences, land surveying and geodesy, architecture, phonetics, economics, electrical engineering, mechanical engineering, civil engineering, computer graphics, cartography, crystallography.
Two triangles are said to be similar if one can be obtained by uniformly expanding the other. This is the case if and only if their corresponding angles are equal, and it occurs for example when two triangles share an angle and the sides opposite to that angle are parallel. The crucial fact about similar triangles is that the lengths of their sides are proportionate. That is, if the longest side of a triangle is twice that of the longest side of a similar triangle, say, then the shortest side will also be twice that of the shortest side of the other triangle, and the median side will be twice that of the other triangle. Also, the ratio of the longest side to the shortest in the first triangle will be the same as the ratio of the longest side to the shortest in the other triangle.
Missing image
Rtriangle.png
Right triangle
Using these facts, one defines trigonometric functions, starting with right triangles, triangles with one right angle (90 degrees or π/2 radians). The longest side in any triangle is the side opposite the largest angle.
Because the sum of the angles in a triangle is 180 degrees or π radians, the largest angle in such a triangle is the right angle.
The longest side in such a triangle is therefore the side opposite the right angle and is called the hypotenuse. Pick two right angled triangles which share a second angle A. These triangles are necessarily similar, and the ratio of the side opposite to A to the hypotenuse will therefore be the same for the two triangles. It will be a number between 0 and 1 which depends only on A; we call it the sine of A and write it as sin(A). Similarly, one can define the cosine of A as the ratio of the side adjacent to A to the hypotenuse.
[itex] \sin A = {\mbox{opp} \over \mbox{hyp}}
\qquad \cos A = {\mbox{adj} \over \mbox{hyp}}
[itex]
These are by far the most important trigonometric functions; other functions can be defined by taking ratios of other sides of the right triangles but they can all be expressed in terms of sine and cosine. These are the tangent, secant, cotangent, and cosecant.
[itex] \tan A = {\sin A \over \cos A} = {\mbox{opp} \over \mbox{adj}}
\qquad \sec A = {1 \over \cos A} = {\mbox{hyp} \over \mbox{adj}} [itex]
[itex] \cot A = {\cos A \over \sin A} = {\mbox{adj} \over \mbox{opp}}
\qquad \csc A = {1 \over \sin A} = {\mbox{hyp} \over \mbox{opp}} [itex]
The sine, cosine and tangent ratios in right triangles can be remembered by SOH CAH TOA (sine-opposite-hypotenuse cosine-adjacent-hypotenuse tangent-opposite-adjacent). See trigonometry mnemonics for other mnemonics.
So far, the trigonometric functions have been defined for angles between 0 and 90 degrees (0 and π/2 radians) only. Using the unit circle, one may extend them to all positive and negative arguments (see trigonometric function).
Once the sine and cosine functions have been tabulated (or computed by a calculator), one can answer virtually all questions about arbitrary triangles, using the law of sines and the law of cosines. These laws can be used to compute the remaining angles and sides of any triangle as soon as two sides and an angle or two angles and a side or three sides are known.
Some mathematicians believe that trigonometry was originally invented to calculate sundials, a traditional exercise in the oldest books. It is also very important for surveying.
• Art and Cultures
• Countries of the World (http://www.academickids.com/encyclopedia/index.php/Countries)
• Space and Astronomy | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 1, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.9404826760292053, "perplexity": 662.7984674413199}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2020-29/segments/1593655906214.53/warc/CC-MAIN-20200710050953-20200710080953-00221.warc.gz"} |
https://www.western-neuralnets.ca/week4/lab4.html | # Introduction to Neural Networks
### Programming Lab 4: Spike-time dependent synaptic plasticity (STDP)
#### Competitive Hebbian learning through STDP
Today, we will implement the model introduced by Song, Miller, and Abbott in the reading for this week. We will be using the simulation code below, in addition to the introduction to synapses and STDP on the Brian website.
from brian2 import *
N = 1000
taum = 10*ms
taupre = 20*ms
taupost = taupre
Ee = 0*mV
vt = -54*mV
vr = -60*mV
El = -74*mV
taue = 5*ms
F = 15*Hz
wmax = .01
dApre = .01
dApost = -dApre * taupre / taupost * 1.05
dApost *= wmax
dApre *= wmax
eqs_neurons = '''
dv/dt = (ge * (Ee-vr) + El - v) / taum : volt
dge/dt = -ge / taue : 1
'''
input = PoissonGroup(N, rates=F)
neurons = NeuronGroup(1, eqs_neurons, threshold='v>vt', reset='v = vr',
method='linear')
S = Synapses(input, neurons,
'''w : 1
dApre/dt = -Apre / taupre : 1 (event-driven)
dApost/dt = -Apost / taupost : 1 (event-driven)''',
on_pre='''ge += w
Apre += dApre
w = clip(w + Apost, 0, wmax)''',
on_post='''Apost += dApost
w = clip(w + Apre, 0, wmax)''',
)
S.connect()
S.w = 'rand() * wmax'
mon = StateMonitor(S, 'w', record=True)
# the resulting ndarray will now have the shape (N,timesteps),
# which will allow accessing the time evolution of individual
# synapses (e.g. mon.w[0] will be the time evolution of the first
# input synapse)
s_mon = SpikeMonitor(input)
run(100*second, report='text')
subplot(311)
plot(S.w / wmax, '.k')
ylabel('Weight / wmax')
xlabel('Synapse index')
subplot(312)
hist(S.w / wmax, 20)
xlabel('Weight / wmax')
subplot(313)
plot(mon.t/second, mon.w[0]/wmax) # timecourse of synaptic weight for first input synapse
xlabel('Time (s)')
ylabel('Weight / wmax')
Experiments: (1) Add inhibitory synaptic inputs to the implementation above. (2) As introduced in the paper, start all synaptic weights at wmax and plot the coefficient of variation ($$C_V = \sigma_\tau / \langle\tau\rangle$$) as a function of time (e.g. divided into short windows of 1 second). (3) Replicate Figure 1a,b from the paper. (4) Replicate Figure 1c,d,e from the paper (in separate simulations). | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 1, "mathjax_asciimath": 1, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.41074296832084656, "perplexity": 25922.613786295315}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2021-10/segments/1614178362513.50/warc/CC-MAIN-20210301121225-20210301151225-00361.warc.gz"} |
https://www.gradesaver.com/textbooks/math/algebra/algebra-2-1st-edition/chapter-13-trigonometric-ratios-and-functions-13-4-evaluate-inverse-trigonometric-functions-13-4-exercises-skill-practice-page-878/15 | Algebra 2 (1st Edition)
$1.98$ radians and $113.6^{\circ}$
We are given that $\cos^{-1} (-0.4)$ In order to get the answer in radians, we need to put the calculator in radians mode. Then, our result will be: $1.98$ radians In order to get the answer in degrees, we need to put the calculator in degrees mode. Then, our result will be: $113.6^{\circ}$ | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.9816862344741821, "perplexity": 247.30697061259096}, "config": {"markdown_headings": false, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2020-10/segments/1581875146342.41/warc/CC-MAIN-20200226115522-20200226145522-00486.warc.gz"} |
http://jmlr.org/papers/v20/18-084.html | ## Minimal Sample Subspace Learning: Theory and Algorithms
Zhenyue Zhang, Yuqing Xia; 20(143):1−57, 2019.
### Abstract
Subspace segmentation, or subspace learning, is a challenging and complicated task in machine learning. This paper builds a primary frame and solid theoretical bases for the minimal subspace segmentation (MSS) of finite samples. The existence and conditional uniqueness of MSS are discussed with conditions generally satisfied in applications. Utilizing weak prior information of MSS, the minimality inspection of segments is further simplified to the prior detection of partitions. The MSS problem is then modeled as a computable optimization problem via the self-expressiveness of samples. A closed form of the representation matrices is first given for the self-expressiveness, and the connection of diagonal blocks is addressed. The MSS model uses a rank restriction on the sum of segment ranks. Theoretically, it can retrieve the minimal sample subspaces that could be heavily intersected. The optimization problem is solved via a basic manifold conjugate gradient algorithm, alternative optimization and hybrid optimization, therein considering solutions to both the primal MSS problem and its pseudo-dual problem. The MSS model is further modified for handling noisy data and solved by an ADMM algorithm. The reported experiments show the strong ability of the MSS method to retrieve minimal sample subspaces that are heavily intersected.
[abs][pdf][bib] | {"extraction_info": {"found_math": false, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.8123943209648132, "perplexity": 1739.6211650225819}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2019-47/segments/1573496664808.68/warc/CC-MAIN-20191112074214-20191112102214-00223.warc.gz"} |
https://pypi.org/project/diffpy.srmise/0.5.2/ | Peak extraction and peak fitting tool for atomic pair distribution functions.
## Project description
DiffPy project tool for unbiased peak extraction from atomic pair distribution functions.
SrMise is an implementation of the ParSCAPE algorithm for peak extraction from atomic pair distribution functions (PDFs). It is designed to function even when a priori knowledge of the physical sample is limited, utilizing the Akaike Information Criterion (AIC) to estimate whether peaks are statistically justified relative to alternate models. Three basic use cases are anticipated for SrMise. The first is peak fitting a user-supplied collections of peaks. The second is peak extraction from a PDF with no (or only partial) user-supplied peaks. The third is an AIC-driven multimodeling analysis where the output of multiple SrMise trials are ranked.
The framework for peak extraction defines peak-like clusters within the data, extracts a single peak within each cluster, and iteratively combines nearby clusters while performing a recursive search on the residual to identify occluded peaks. Eventually this results in a single global cluster containing many peaks fit over all the data. Over- and underfitting are discouraged by use of the AIC when adding or, during a pruning step, removing peaks. Termination effects, which can lead to physically spurious peaks in the PDF, are incorporated in the mathematical peak model and the pruning step attempts to remove peaks which are fit better as termination ripples due to another peak.
Where possible, SrMise provides physically reasonable default values for extraction parameters. However, the PDF baseline should be estimated by the user before extraction, or by performing provisional peak extraction with varying baseline parameters. The package defines a linear (crystalline) baseline, arbitrary polynomial baseline, a spherical nanoparticle baseline, and an arbitrary baseline interpolated from a list of user-supplied values. In addition, PDFs with accurate experimentally-determined uncertainties are necessary to provide the most reliable results, but historically such PDFs are rare. In the absence of accurate uncertainties an ad hoc uncertainty must be specified.
## Getting Started
The diffpy.srmise package requires Python 2.6 or 2.7 and the following software:
• setuptools - software distribution tools for Python
• NumPy - numerical mathematics and fast array operations for Python
• SciPy - scientific libraries for Python
• matplotlib - python plotting library
See the SrMise license for terms and conditions of use. Detailed installation instructions for the Windows, Mac OS X, and Linux platforms follow.
### Windows
Several prebuilt Python distributions for Windows include all the prerequisite software required to run SrMise, and installing one of these is the simplest way to get started. These distributions are usually free for individual and/or academic use, but some also have commercial version. Links to executables, installation instructions, and licensing information for some popular options are listed below.
Alternately, individual Windows executables for Python and the required components can be downloaded and installed. The official Windows releases of Numpy and SciPy do not currently support 64-bit Python installations, so be sure to download the 32-bit versions of these packages.
After installing Python and the required packages, the simplest way to obtain SrMise is using pip to download and install the latest release from the Python Package Index (PyPI). Open a command window by running cmd from the Start Menu’s application search box (Windows 7/8/10) or Run command (Windows Vista and earlier). Verify that the pip program is installed by running
pip --version
If this command is not found, download and run get-pip.py, which will install both it and setuptools. For example, if the file were downloaded to the desktop, a Windows user named MyName should run the following from the command line:
cd C:\Users\MyName\Desktop
python get-pip.py
pip install diffpy.srmise
### Mac OS X
For Mac OS X systems with the MacPorts package manager, the required software can be installed with
sudo port install \
python27 py27-setuptools py27-numpy py27-scipy py27-matplotlib
When installing for MacPorts, make sure the MacPorts bin directory is the first in the system PATH and that python27 is selected as the default Python version in MacPorts:
sudo port select --set python python27
The simplest way to obtain diffpy.srmise on Mac OS X systems is using pip to download and install the latest release from PyPI.
sudo pip install diffpy.srmise
Those who prefer to install from sources may download them from the GitHub or PyPI pages for SrMise. Uncompress them to a directory, and from that directory run
sudo python setup.py install
This installs diffpy.srmise for all users in the default system location. If administrator (root) access is not available, see the usage info from python setup.py install --help for options to install to user-writable directories.
### Linux
On Ubuntu and Debian Linux, the required software can easily be installed using the system package manager:
sudo apt-get install \
python-setuptools python-numpy python-scipy python-matplotlib
Similarly, on Fedora:
sudo yum install python-setuptools numpy scipy python-matplotlib
For other Linux distributions consult the appropriate package manager.
The simplest way to obtain diffpy.srmise on Linux systems is using pip to download and install the latest release from the PyPI.
sudo pip install diffpy.srmise
Those who prefer to install from sources may download them from the GitHub or PyPI pages for SrMise. Uncompress them to a directory, and from that directory run
sudo python setup.py install
This installs diffpy.srmise for all users in the default system location. If administrator (root) access is not available, see the usage info from python setup.py install --help for options to install to user-writable directories.
## DEVELOPMENT
diffpy.srmise is open-source software developed with support of the Center of Research Excellence in Complex Materials at Michigan State University, in cooperation with the DiffPy-CMI complex modeling initiative at the Brookhaven National Laboratory. The diffpy.srmise sources are hosted at https://github.com/diffpy/diffpy.srmise.
Feel free to fork the project and contribute. To install diffpy.srmise in a development mode, with its sources being directly used by Python rather than copied to a package directory, use
python setup.py develop --user
## ACKNOWLEDGEMENT
The source code of pdfdataset.py was derived from diffpy.pdfgui.
## CONTACTS
http://www.diffpy.org/
or email Prof. Simon Billinge at sb2896@columbia.edu.
## Project details
Uploaded source | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 1, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.1882113218307495, "perplexity": 6265.844243584926}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2023-06/segments/1674764500904.44/warc/CC-MAIN-20230208191211-20230208221211-00243.warc.gz"} |
https://worldwidescience.org/topicpages/a/absolute+nodal+coordinate.html | #### Sample records for absolute nodal coordinate
1. Application of the Absolute Nodal Co-Ordinate Formulation to Multibody System Dynamics
Science.gov (United States)
Escalona, J. L.; Hussien, H. A.; Shabana, A. A.
1998-07-01
The floating frame of reference formulation is currently the most widely used approach in flexible multibody simulations. The use of this approach, however, has been limited to small deformation problems. In this investigation, the computer implementation of the newabsolute nodal co-ordinate formulationand its use in the small and large deformation analysis of flexible multibody systems that consist of interconnected bodies are discussed. While in the floating frame of reference formulation a mixed set of absolute reference and local elastic co-ordinates are used, in the absolute nodal co-ordinate formulation only absolute co-ordinates are used. In the absolute nodal co-ordinate formulation, new interpretation of the nodal co-ordinates of the finite elements is used. No infinitesimal or finite rotations are used as nodal co-ordinates from beams and plates, instead, global slopes are used to define the element nodal co-ordinates. Using this interpretation of the element co-ordinates, beams and plates can be considered as isoparametric elements, and as a result, exact modelling of the rigid body dynamics can be obtained using the element shape function and the absolute nodal co-ordinates. Unlike the floating frame of reference approach, no co-ordinate transformation is required in order to determine the element inertia. The mass matrix of the finite elements is a constant matrix, and therefore, the centrifugal and Coriolis forces are equal to zero when the absolute nodal co-ordinate formulation is used. Another advantage of using the absolute nodal co-ordinate formulation in the dynamic simulation of multibody systems is its simplicity in imposing some of the joint constraints and also its simplicity in formulating the generalized forces due to spring-damper elements. The results obtained in this investigation show an excellent agreement with the results obtained using the floating frame of reference formulation when large rotation-small deformation problems are
2. Aerothermoelastic analysis of panel flutter based on the absolute nodal coordinate formulation
International Nuclear Information System (INIS)
Panels of reentry vehicles are subjected to a wide range of flow conditions during ascent and reentry phases. The flow can vary from subsonic continuum flow to hypersonic rarefied flow with wide ranging dynamic pressure and associated aerodynamic heating. One of the main design considerations is the assurance of safety against panel flutter under the flow conditions characterized by sever thermal environment. This paper deals with supersonic/hypersonic flutter analysis of panels exposed to a temperature field. A 3-D rectangular plate element of variable thickness based on absolute nodal coordinate formulation (ANCF) has been developed for the structural model and subjected to an assumed thermal profile that can result from any residual heat seeping into the metallic panels through the thermal protection systems. A continuum mechanics approach for the definition of the elastic forces within the finite element is considered. Both shear strain and transverse normal strain are taken into account. The aerodynamic force is evaluated by considering the first-order piston theory to linearize the potential flow and is coupled with the structural model to account for pressure loading. A provision is made to take into account the effect of arbitrary flow directions with respect to the panel edges. Aerothermoelastic equations using ANCF are derived and solved numerically. Values of critical dynamic pressure are obtained by a modal approach, in which the mode shapes are obtained by ANCF. A detailed parametric study is carried out to observe the effects of different temperature loadings, flow angle directions, and aspect ratios on the flutter boundary
3. Aerothermoelastic analysis of panel flutter based on the absolute nodal coordinate formulation
Energy Technology Data Exchange (ETDEWEB)
Abbas, Laith K., E-mail: laithabbass@yahoo.com; Rui, Xiaoting, E-mail: ruixt@163.com [Nanjing University of Science and Technology, Institute of Launch Dynamics (China); Marzocca, Piergiovanni, E-mail: pmarzocc@clarkson.edu [Clarkson University, Mechanical and Aeronautical Engineering Department (United States)
2015-02-15
Panels of reentry vehicles are subjected to a wide range of flow conditions during ascent and reentry phases. The flow can vary from subsonic continuum flow to hypersonic rarefied flow with wide ranging dynamic pressure and associated aerodynamic heating. One of the main design considerations is the assurance of safety against panel flutter under the flow conditions characterized by sever thermal environment. This paper deals with supersonic/hypersonic flutter analysis of panels exposed to a temperature field. A 3-D rectangular plate element of variable thickness based on absolute nodal coordinate formulation (ANCF) has been developed for the structural model and subjected to an assumed thermal profile that can result from any residual heat seeping into the metallic panels through the thermal protection systems. A continuum mechanics approach for the definition of the elastic forces within the finite element is considered. Both shear strain and transverse normal strain are taken into account. The aerodynamic force is evaluated by considering the first-order piston theory to linearize the potential flow and is coupled with the structural model to account for pressure loading. A provision is made to take into account the effect of arbitrary flow directions with respect to the panel edges. Aerothermoelastic equations using ANCF are derived and solved numerically. Values of critical dynamic pressure are obtained by a modal approach, in which the mode shapes are obtained by ANCF. A detailed parametric study is carried out to observe the effects of different temperature loadings, flow angle directions, and aspect ratios on the flutter boundary.
4. Nonlinear Absolute Nodal Coordinate Formulation of a Flexible Beam Considering Shear Effect
Institute of Scientific and Technical Information of China (English)
LIU Jin-yang; SHEN Ling-jie; HONG Jia-zhen
2005-01-01
Nonlinear modeling of a flexible beam with large deformation was investigated. Absolute nodal cooridnate formulation is employed to describe the motion, and Lagrange equations of motion of a flexible beam are derived based on the geometric nonlinear theory. Different from the previous nonlinear formulation with EulerBernoulli assumption, the shear strain and transverse normal strain are taken into account. Computational example of a flexible pendulum with a tip mass is given to show the effects of the shear strain and transverse normal strain. The constant total energy verifies the correctness of the present formulation.
5. 基于绝对节点坐标法的发动机曲柄滑块系统动态性能研究∗%Dynamic Analysis of Engine Slider-crank Based on the Absolute Nodal Coordinate Formulation
Institute of Scientific and Technical Information of China (English)
赵君; 门洪; 冯玉昌; 张秀宇
2015-01-01
The slider-crank in engine is one of the important mechanisms in automobiles which transports force and displacement. The flexible deformation of the crank and the connecting rod will affect the dynamic performance of the engine. The flexible dynamic model of the engine slider-crank is established base on the absolute nodal coordinate formulation ( ANCF) . The influence of the flexible deformation on the displace-ment of the piston is studied. The equation which is used to calculate the engine compression ratio is given and the relationship between the compression ratio and the displacement of the slider is studied. The dynamic model of the system is simulated with the help of MATLAB and the engine compression ratio of both rigid and flexible system is calculated. The results show that the flexible deformation of the system reduces the en-gine compression ratio and is not conducive to the engine fuel economy.%发动机曲柄滑块机构是汽车中重要的传递力和位移的机构。以曲柄和连杆工作过程中产生的柔性变形为对象，研究对发动机动力性能带来影响。采用绝对节点坐标法，建立系统柔体动力学模型，分析曲柄和连杆在工作过程中的柔性变形对活塞运动位置的影响。利用发动机压缩比评价发动机动态性能，给出某型发动机压缩比计算公式，找到影响发动机压缩比的关键参数。利用MATLAB对曲柄滑块系统进行动力学仿真，分别考虑刚体和柔性体情况，计算活塞运动到上止点的位置，进而计算发动机压缩比。通过仿真结果比对表明，曲柄滑块的柔性变形减小了发动机压缩比，降低了发动机性能，不利于发动机的燃油经济性。
6. High-precision absolute coordinate measurement using frequency scanned interferometry
International Nuclear Information System (INIS)
We reported previously on measurements of absolute distance with frequency scanned interferometry (FSI) method [1, 2]. In this paper, we extend the FSI method into 2-dimensional and 3-dimensional high-precision absolute coordinate measurements using a single laser. Absolute position is determined by several related absolute distances measured simultaneously. The achieved precision on X and Y in 2- and in 3-dimensional measurements is confirmed to be below 1 μm, while the precision in Z (in 3D case) is found to be about 2 μm. The last one is limited by the accuracy of the available translational stage used in the tests. A much more powerful laser and a better real-time data acquirement system will be required in case of measurements of larger absolute distances
7. Dynamic Analysis of Offshore Oil Pipe Installation Using the Absolute Nodal Coordinate Formulation
DEFF Research Database (Denmark)
Nielsen, Jimmy D; Madsen, Søren B; Hyldahl, Per Christian;
2013-01-01
centrifugal and Coriolis forces [12]. This makes the method attractive for multibody dynamics implementation. The focus in this paper is the application of ANCF beam elements and their performance on large deformation dynamic analysis. Large dynamic deformation is characteristic for the installation process...
8. Absolute flatness testing of skip-flat interferometry by matrix analysis in polar coordinates.
Science.gov (United States)
Han, Zhi-Gang; Yin, Lu; Chen, Lei; Zhu, Ri-Hong
2016-03-20
A new method utilizing matrix analysis in polar coordinates has been presented for absolute testing of skip-flat interferometry. The retrieval of the absolute profile mainly includes three steps: (1) transform the wavefront maps of the two cavity measurements into data in polar coordinates; (2) retrieve the profile of the reflective flat in polar coordinates by matrix analysis; and (3) transform the profile of the reflective flat back into data in Cartesian coordinates and retrieve the profile of the sample. Simulation of synthetic surface data has been provided, showing the capability of the approach to achieve an accuracy of the order of 0.01 nm RMS. The absolute profile can be retrieved by a set of closed mathematical formulas without polynomial fitting of wavefront maps or the iterative evaluation of an error function, making the new method more efficient for absolute testing.
9. Using Mean Absolute Relative Phase, Deviation Phase and Point-Estimation Relative Phase to Measure Postural Coordination in a Serial Reaching Task.
Science.gov (United States)
Galgon, Anne K; Shewokis, Patricia A
2016-03-01
10. Easy Absolute Values? Absolutely
Science.gov (United States)
Taylor, Sharon E.; Mittag, Kathleen Cage
2015-01-01
The authors teach a problem-solving course for preservice middle-grades education majors that includes concepts dealing with absolute-value computations, equations, and inequalities. Many of these students like mathematics and plan to teach it, so they are adept at symbolic manipulations. Getting them to think differently about a concept that they…
11. Application of articulated absolute co-ordinate measuring machine for quality control in manufacturing of ELM control coil
International Nuclear Information System (INIS)
Under India-EU collaboration, Institute for Plasma Research had undertaken an engineering feasibility initiative aimed at developing a 1:1 prototype Edge Localized Modes control coils (ELM CC) for Joint European Torus (JET). The ELM coils comprised of winding pack made of CuCrZr conductor encased in Inconel 625 casing. The ELM control coils are designed in saddle coil configuration having toroidal and poloidal curves similar to that of JET vacuum vessel. ELM coil are in-vessels coils forming the primary boundary with torus vacuum which demands stringent requirement for its quality aspects. The dimensional accuracies of winding pack and casing are critical for its encasing and remote assembly inside vacuum vessel. The articulated arm co-ordinate measuring machine (AACMM) has been extensively used for dimensional metrology of ELM CC from winding to its encasing. The inspection methodology and procedures using noncontact technique for ELM CC with AACMM has been developed and established with extensive trials. The winding pack, their formers and final ELM control coils has been systematically investigated for their dimensional accuracies with AACMM. The effectiveness of AACMM based evaluation for quality control in fabrication of 1:1 prototype of ELM CC has been presented in this paper. (author)
12. A Manifesto of Nodalism
Directory of Open Access Journals (Sweden)
2014-12-01
Full Text Available This paper proposes the notion of Nodalism as a means describing contemporary culture and of understanding my own creative practice in electronic music composition. It draws on theories and ideas from Kirby, Bauman, Bourriaud, Deleuze, Guatarri, and Gochenour, to demonstrate how networks of ideas or connectionist neural models of cognitive behaviour can be used to contextualize, understand and become a creative tool for the creation of contemporary electronic music.
13. LATE ONSET ATRIOVENTRICULAR NODAL TACHYCARDIA
NARCIS (Netherlands)
PENTINGA, ML; MEEDER, JG; CRIJNS, HJGM; DEMUINCK, ED; WIESFELD, ACP; LIE, KI
1993-01-01
AV nodal tachycardia may present at any age, but onset in late adulthood is considered uncommon. To evaluate whether onset of AV nodal tachycardias at older age is related to organic heart disease (possibly setting the stage for re-entry due to degenerative structural changes) 32 consecutive patient
14. The SINTRAN III NODAL system
International Nuclear Information System (INIS)
NODAL is a high level programming language based on FOCAL and SNOBOL4, with some influence from BASIC. The language was developed to operate on the computer network controlling the SPS accelerator at CERN. NODAL is an interpretive language designed for interactive use. This is the most important aspect of the language, and is reflected in its structure. The interactive facilities make it possible to write, debug and modify programs much faster than with compiler based languages like FORTRAN and ALGOL. Apart from a few minor modifications, the basic part of the Oslo University NODAL system does not differ from the CERN version. However, the Oslo University implementation has been expanded with new functions which enable the user to execute many of the SINTRAN III monitor calls from the NODAL level. In particular the most important RT monitor calls have been implemented in this way, a property which renders possible the use of NODAL as a RT program administrator. (JIW)
NARCIS (Netherlands)
J.G.M. van Marrewijk (Charles)
2008-01-01
textabstractA country is said to have an absolute advantage over another country in the production of a good or service if it can produce that good or service using fewer real resources. Equivalently, using the same inputs, the country can produce more output. The concept of absolute advantage can a
16. Topological semimetals and nodal superconductors
Science.gov (United States)
Chang, Po-Yao
Besides topological band insulators, which have a full bulk gap, there are also gapless phases of matter that belong to the broad class of topological materials, such as topological semimetals and nodal superconductors. We systematically study these gapless topological phases described by the Bloch and Bogoliubov-de Gennes Hamiltonians. We discuss a generalized bulk-boundary correspondence, which relates the topological properties in the bulk of gapless topological phases and the protected zero-energy states at the boundary. We study examples of gapless topological phases, focusing in particular on nodal superconductors, such as nodal noncentrosymmetric superconductors (NCSs). We compute the surface density of states of nodal NCSs and interpret experimental measurements of surface states. In addition, we investigate Majorana vortex-bound states in both nodal and fully gapped NCSs using numerical and analytical methods. We show that different topological properties of the bulk Bogoliubov-quasiparticle wave functions reflect themselves in different types of zero-energy vortex-bound states. In particular, in the case of NCSs with tetragonal point-group symmetry, we find that the stability of these Majorana zero modes is guaranteed by a combination of reflection, time-reversal, and particle-hole symmetries. Finally, by using K-theory arguments and a dimensional reduction procedure from higher-dimensional topological insulators and superconductors, we derive a classification of topologically stable Fermi surfaces in semimetals and nodal lines in superconductors.
17. NODAL interpreter for CP/M
International Nuclear Information System (INIS)
A NODAL interpreter which works under CP/M operating system is made for microcomputers. This interpreter language named NODAL-80 has a similar structure to the NODAL of SPS, but its commands, variables, and expressions are modified to increase the flexibility of programming. NODAL-80 also uses a simple intermediate code to make the execution speed fast without imposing any restriction on the dynamic feature of NODAL language. (author)
18. Absolute beginners
OpenAIRE
Costa, Carlos Casimiro da; Costa, Jacinta Casimiro da
2012-01-01
Tomorrow, I m recovering my Thursday child as an absolute beginner , Transporting you to the essential touch of surface skin and space, Only for you, i do not regret, looking for education in a materia set. My love is your love , my materiality is you making things, The legacy of our ethnography, craftsmen s old and disappear, make me strong hard feelings, Recovering experiences and knowledge sprinkled in powder of stone, wood and metal ( ) reflecting in your dirty face the ...
19. Nodal bradycardia induced by tocainide.
OpenAIRE
Mandal, S. K.; Datta, S.K.
1983-01-01
A case of tocainide-induced nodal bradycardia in standard recommended dose is reported. There was no recurrence when the drug was subsequently reintroduced in a reduced dosage. It is suggested that in the elderly, tocainide should be used in a lower dosage than normally recommended.
20. Super-nodal methods for space-time kinetics
Science.gov (United States)
Mertyurek, Ugur
The purpose of this research has been to develop an advanced Super-Nodal method to reduce the run time of 3-D core neutronics models, such as in the NESTLE reactor core simulator and FORMOSA nuclear fuel management optimization codes. Computational performance of the neutronics model is increased by reducing the number of spatial nodes used in the core modeling. However, as the number of spatial nodes decreases, the error in the solution increases. The Super-Nodal method reduces the error associated with the use of coarse nodes in the analyses by providing a new set of cross sections and ADFs (Assembly Discontinuity Factors) for the new nodalization. These so called homogenization parameters are obtained by employing consistent collapsing technique. During this research a new type of singularity, namely "fundamental mode singularity", is addressed in the ANM (Analytical Nodal Method) solution. The "Coordinate Shifting" approach is developed as a method to address this singularity. Also, the "Buckling Shifting" approach is developed as an alternative and more accurate method to address the zero buckling singularity, which is a more common and well known singularity problem in the ANM solution. In the course of addressing the treatment of these singularities, an effort was made to provide better and more robust results from the Super-Nodal method by developing several new methods for determining the transverse leakage and collapsed diffusion coefficient, which generally are the two main approximations in the ANM methodology. Unfortunately, the proposed new transverse leakage and diffusion coefficient approximations failed to provide a consistent improvement to the current methodology. However, improvement in the Super-Nodal solution is achieved by updating the homogenization parameters at several time points during a transient. The update is achieved by employing a refinement technique similar to pin-power reconstruction. A simple error analysis based on the relative
1. Absolute Summ
Science.gov (United States)
Phillips, Alfred, Jr.
Summ means the entirety of the multiverse. It seems clear, from the inflation theories of A. Guth and others, that the creation of many universes is plausible. We argue that Absolute cosmological ideas, not unlike those of I. Newton, may be consistent with dynamic multiverse creations. As suggested in W. Heisenberg's uncertainty principle, and with the Anthropic Principle defended by S. Hawking, et al., human consciousness, buttressed by findings of neuroscience, may have to be considered in our models. Predictability, as A. Einstein realized with Invariants and General Relativity, may be required for new ideas to be part of physics. We present here a two postulate model geared to an Absolute Summ. The seedbed of this work is part of Akhnaton's philosophy (see S. Freud, Moses and Monotheism). Most important, however, is that the structure of human consciousness, manifest in Kenya's Rift Valley 200,000 years ago as Homo sapiens, who were the culmination of the six million year co-creation process of Hominins and Nature in Africa, allows us to do the physics that we do. .
2. Hilbert-Mumford criterion for nodal curves
CERN Document Server
Li, Jun
2011-01-01
We prove by Hilbert-Mumford criterion that a slope stable polarized weighted pointed nodal curve is Chow asymptotic stable. This generalizes the result of Caporaso on stability of polarized nodal curves, and of Hasset on weighted pointed stable curves polarized by the weighted dualizing sheaves. It also solved a question raised by Mumford and Gieseker to prove the Chow asymptotic stability of stable nodal curves by Hilbert-Mumford criterion.
3. Principal -bundles on Nodal Curves
Usha N Bhosle
2001-08-01
Let be a connected semisimple affine algebraic group defined over . We study the relation between stable, semistable -bundles on a nodal curve and representations of the fundamental group of . This study is done by extending the notion of (generalized) parabolic vector bundles to principal -bundles on the desingularization of and using the correspondence between them and principal -bundles on . We give an isomorphism of the stack of generalized parabolic bundles on with a quotient stack associated to loop groups. We show that if is simple and simply connected then the Picard group of the stack of principal -bundles on is isomorphic to ⊕ , being the number of components of .
4. Error analysis of the quartic nodal expansion method for slab geometry
Energy Technology Data Exchange (ETDEWEB)
Penland, R.C.; Turinsky, P.J. [North Carolina State Univ., Raleigh, NC (United States); Azmy, Y.Y. [Oak Ridge National Lab., TN (United States)
1995-02-01
This paper presents an analysis of the quartic polynomial Nodal Expansion Method (NEM) for one-dimensional neutron diffusion calculations. As part of an ongoing effort to develop an adaptive mesh refinement strategy for use in state-of-the-art nodal kinetics codes, we derive a priori error bounds on the computed solution for uniform meshes and validate them using a simple test problem. Predicted error bounds are found to be greater than computed maximum absolute errors by no more than a factor of six allowing mesh size selection to reflect desired accuracy. We also quantify the rapid convergence in the NEM computed solution as a function of mesh size.
5. The Nudo, Rollo, Melon codes and nodal correlations
International Nuclear Information System (INIS)
Analysis of nodal calculation and checking results by the reference reactor experimental data. Nudo code description, adapting experimental data to nodal calculations. Rollo, Melon codes as improvement in the cycle life calculations of albedos, mixing parameters and nodal correlations. (author)
6. Impacts of Contingency Reserve on Nodal Price and Nodal Reliability Risk in Deregulated Power Systems
DEFF Research Database (Denmark)
Zhao, Qian; Wang, Peng; Goel, Lalit;
2013-01-01
The deregulation of power systems allows customers to participate in power market operation. In deregulated power systems, nodal price and nodal reliability are adopted to represent locational operation cost and reliability performance. Since contingency reserve (CR) plays an important role in re...... and CR allocation. Customers' nodal unit commitment risk and nodal energy interruption have been evaluated through contingency analysis. Customers' reliability cost including reserve service cost and energy interruption cost have also been evaluated.......The deregulation of power systems allows customers to participate in power market operation. In deregulated power systems, nodal price and nodal reliability are adopted to represent locational operation cost and reliability performance. Since contingency reserve (CR) plays an important role...
7. Teaching Absolute Value Meaningfully
Science.gov (United States)
2012-01-01
What is the meaning of absolute value? And why do teachers teach students how to solve absolute value equations? Absolute value is a concept introduced in first-year algebra and then reinforced in later courses. Various authors have suggested instructional methods for teaching absolute value to high school students (Wei 2005; Stallings-Roberts…
8. Optical conductivity of nodal metals
Science.gov (United States)
Homes, C. C.; Gu, G. D.; Tu, J. J.; Li, J.; Akrap, A.
2014-03-01
Fermi liquid theory is remarkably successful in describing the transport and optical properties of metals; at frequencies higher than the scattering rate, the optical conductivity adopts the well-known power law behavior σ1(ω) ~ω-2 . We have observed an unusual non-Fermi liquid response σ1(ω) ~ω - 1 +/- 0 . 2 in the ground states of several quasi two-dimensional cuprate (optimally doped Bi2Sr2CaCu2O8+δ, optimally and underdoped YBa2Cu3O7-δ) and iron-based materials (AFe2As2, A = Ba, Ca) which undergo electronic or magnetic phase transitions resulting in dramatically reduced or nodal Fermi surfaces. The identification of an inverse (or fractional) power-law behavior in the residual optical conductivity now permits the removal of this contribution, revealing the direct transitions across the gap and allowing the nature of the electron-boson coupling to be probed. The non-Fermi liquid behavior in these systems may be the result of a common Fermi surface topology of Dirac cone-like features in the electronic dispersion. Supported by the DOE under Contract No. DE-AC02-98CH10886.
9. Twisted Vector Bundles on Pointed Nodal Curves
Ivan Kausz
2005-05-01
Motivated by the quest for a good compactification of the moduli space of -bundles on a nodal curve we establish a striking relationship between Abramovich’s and Vistoli’s twisted bundles and Gieseker vector bundles.
10. Aircraft Nodal Data Acquisition System (ANDAS) Project
Data.gov (United States)
National Aeronautics and Space Administration — Development of an Aircraft Nodal Data Acquisition System (ANDAS) is proposed. The proposed methodology employs the development of a very thin (135m) hybrid...
11. Aircraft Nodal Data Acquisition System (ANDAS) Project
Data.gov (United States)
National Aeronautics and Space Administration — Development of an Aircraft Nodal Data Acquisition System (ANDAS) based upon the short haul Zigbee networking standard is proposed. It employs a very thin (135 um)...
12. Eosinophil count - absolute
Science.gov (United States)
Eosinophils; Absolute eosinophil count ... the white blood cell count to give the absolute eosinophil count. ... than 500 cells per microliter (cells/mcL). Normal value ranges may vary slightly among different laboratories. Talk ...
13. An exact nonlinear hybrid-coordinate formulation for flexible multibody systems
Institute of Scientific and Technical Information of China (English)
Jinyang Liu; Jiazhen Hong; Lin Cui
2007-01-01
The previous low-order approximate nonlinear formulations succeeded in capturing the stiffening terms,but failed in simulation of mechanical systems with large deformation due to the neglect of the high-order deforma-tion terms. In this paper, a new hybrid-coordinate formu-lation is proposed, which is suitable for flexible multibody systems with large deformation. On the basis of exact strain-displacement relation, equations of motion for flexible multi-body system are derived by using virtual work principle. A matrix separation method is put forward to improve the efficiency of the calculation. Agreement of the present results with those obtained by absolute nodal coordinate formula-tion (ANCF) verifies the correctness of the proposed formu-lation. Furthermore, the present results are compared with those obtained by use of the linear model and the low-order approximate nonlinear model to show the suitability of the proposed models.
14. A lymph nodal capillary-cavernous hemangioma.
Science.gov (United States)
Dellachà, A; Fulcheri, E; Campisi, C
1999-09-01
A capillary-cavernous hemangioma in an obturator lymph node was found incidentally in a 64 year-old woman who had undergone unilateral salpingo-oophorectomy and lymphadenectomy for an ovarian neoplasm. Vascular tumors of lymph nodes are briefly reviewed including eight previously described nodal capillary-cavernous hemangiomas. The association with other splanchnic hemangiomas is pointed out and the likelihood that the lesion is a hamartoma rather than a true neoplasm is addressed. Despite its rarity, this entity needs to be recognized by lymphologists who image lymph nodes by lymphangiography as well as by lymph nodal pathologists. PMID:10494525
15. Braided nodal lines in wave superpositions
CERN Document Server
Dennis, M R
2003-01-01
Nodal lines (phase singularities, optical vortices) are the generic interference fringes of complex scalar waves. Here, an exact complex solution of the time independent wave equation (Helmholtz equation) is considered, possessing nodal lines which are braided in the form of a borromean, or pig-tail braid. The braid field is a superposition of counterpropagating, counterrotating, non-coaxial order 3 Bessel beams, and a plane wave whose propagation is perpendicular to that of the beams. The construction is structurally stable, and can be generalized to a limited class of other braids.
16. Nodal Variational Principle for Excited States
CERN Document Server
Zahariev, Federico; Levy, Mel
2016-01-01
It is proven that the exact excited-state wavefunction and energy may be obtained by minimizing the energy expectation value of a trial wave function that is constrained only to have the correct nodes of the state of interest. This excited-state nodal minimum principle has the advantage that it requires neither minimization with the con- straint of wavefunction orthogonality to all lower eigenstates nor the antisymmetry of the trial wavefunctions. It is also found that the minimization over the entire space can be partitioned into several in- terconnected minimizations within the individual nodal regions, and the exact excited-state energy may be obtained by a minimization in just one or several of these nodal regions. For the proofs of the the- orem, it is observed that the many-electron eigenfunction, restricted to a nodal region, is equivalent to a ground state wavefunction of one electron in a higher dimensional space; and an explicit excited-state energy variational expression is obtained by generalizing...
17. Comparison of neutronic transport equation resolution nodal methods
International Nuclear Information System (INIS)
In this work, some transport equation resolution nodal methods are comparatively studied: the constant-constant (CC), linear-nodal (LN) and the constant-quadratic (CQ). A nodal scheme equivalent to finite differences has been used for its programming, permitting its inclusion in existing codes. Some bidimensional problems have been solved, showing that linear-nodal (LN) are, in general, obtained with accuracy in CPU shorter times. (Author)
18. Absolute nuclear material assay
Science.gov (United States)
Prasad, Manoj K.; Snyderman, Neal J.; Rowland, Mark S.
2010-07-13
A method of absolute nuclear material assay of an unknown source comprising counting neutrons from the unknown source and providing an absolute nuclear material assay utilizing a model to optimally compare to the measured count distributions. In one embodiment, the step of providing an absolute nuclear material assay comprises utilizing a random sampling of analytically computed fission chain distributions to generate a continuous time-evolving sequence of event-counts by spreading the fission chain distribution in time.
19. ABSOLUTE NEUTRINO MASSES
DEFF Research Database (Denmark)
Schechter, J.; Shahid, M. N.
2012-01-01
We discuss the possibility of using experiments timing the propagation of neutrino beams over large distances to help determine the absolute masses of the three neutrinos.......We discuss the possibility of using experiments timing the propagation of neutrino beams over large distances to help determine the absolute masses of the three neutrinos....
20. Lunar nodal tide in the Baltic Sea
Directory of Open Access Journals (Sweden)
Andrzej Wróblewski
2001-03-01
Full Text Available The nodal tide in the Baltic Sea was studied on the basis of the Stockholm tide-gauge readings for 1825-1984; data from the tide gauge at Swinoujscie for the same period provided comparative material. The Stockholm readings are highly accurate and are considered representative of sea levels in the whole Baltic; hence, the final computations were performed for the readings from this particular tide gauge for the period 1888-1980. The tidal amplitude obtained from measurements uncorrected for atmospheric pressure or wind field was compared with that forced only by atmospheric effects. The amplitude of the recorded nodal tide was the same as the equilibrium tide amplitude calculated for Stockholm. Calculations for equilibrium tide amplitudes were also performed for the extreme latitudes of the Baltic basin.
1. Nodal yield in selective neck dissection
DEFF Research Database (Denmark)
Norling, Rikke; Therkildsen, Marianne H; Bradley, Patrick J;
2013-01-01
The total lymph node yield in neck dissection is highly variable and depends on anatomical, surgical and pathological parameters. A minimum yield of six lymph nodes for a selective neck dissection (SND) as recommended in guidelines lies in the lower range of the reported clinical nodal yields....... A future application of a lymph node ratio may improve the risk stratification of head and neck cancer patients. However, this will require a higher number of retrieved lymph nodes....
2. Acceleration of the FERM nodal program
International Nuclear Information System (INIS)
It was tested three acceleration methods trying to reduce the number of outer iterations in the FERM nodal program. The results obtained indicated that the Chebychev polynomial acceleration method with variable degree results in a economy of 50% in the computer time. Otherwise, the acceleration method by source asymptotic extrapolation or by zonal rebalance did not result in economy of the global computer time, however some acceleration had been verified in outer iterations. (M.C.K.)
3. Acceleration of the nodal program FERM
International Nuclear Information System (INIS)
Acceleration of the nodal FERM was tried by three acceleration schemes. Results of the calculations showed the best acceleration with the Tchebyshev method where the savings in the computing time were of the order of 50%. Acceleration with the Assymptotic Source Extrapoltation Method and with the Coarse-Mesh Rebalancing Method did not result in any improvement on the global computational time, although a reduction in the number of outer iterations was observed. (Author)
4. Nodal methods in numerical reactor calculations
International Nuclear Information System (INIS)
The present work describes the antecedents, developments and applications started in 1972 with Prof. Hennart who was invited to be part of the staff of the Nuclear Engineering Department at the School of Physics and Mathematics of the National Polytechnic Institute. Since that time and up to 1981, several master theses based on classical finite element methods were developed with applications in point kinetics and in the steady state as well as the time dependent multigroup diffusion equations. After this period the emphasis moved to nodal finite elements in 1, 2 and 3D cartesian geometries. All the thesis were devoted to the numerical solution of the neutron multigroup diffusion and transport equations, few of them including the time dependence, most of them related with steady state diffusion equations. The main contributions were as follows: high order nodal schemes for the primal and mixed forms of the diffusion equations, block-centered finite-differences methods, post-processing, composite nodal finite elements for hexagons, and weakly and strongly discontinuous schemes for the transport equation. Some of these are now being used by several researchers involved in nuclear fuel management. (Author)
5. NGS Absolute Gravity Data
Data.gov (United States)
National Oceanic and Atmospheric Administration, Department of Commerce — The NGS Absolute Gravity data (78 stations) was received in July 1993. Principal gravity parameters include Gravity Value, Uncertainty, and Vertical Gradient. The...
6. Absolute Pitch on Music
OpenAIRE
2008-01-01
Musicians are debated people in the academic circles with the claim of they have both various characteristics and different cognitive personalities on the analogy those other people. One of these different characteristics is absolute pitch ability. Absolute pitch (AP) is a cognitive ability which can be characterized as to identify any tones (labeling) at a given pitch without using any external references. According to the different studies which were held in different times, the prevalence ...
7. Absolute polarimetry at RHIC
OpenAIRE
Okada, H.; Alekseev, I.; Bravar, A; Bunce, G.; Dhawan, S.; Eyser, K. O.; Gill, R; Haeberli, W.; Huang, H.; Jinnouchi, O.; Makdisi, Y.; Nakagawa, I.; Nass, A.; Saito, N; Stephenson, E.
2007-01-01
Precise and absolute beam polarization measurements are critical for the RHIC spin physics program. Because all experimental spin-dependent results are normalized by beam polarization, the normalization uncertainty contributes directly to final physics uncertainties. We aimed to perform the beam polarization measurement to an accuracy of $\\Delta P_{beam}/P_{beam} < 5%$. The absolute polarimeter consists of Polarized Atomic Hydrogen Gas Jet Target and left-right pairs of silicon strip detector...
8. Nodal curves on surfaces of general type
CERN Document Server
Chiantini, L; Chiantini, Luca; Sernesi, Edoardo
1996-01-01
We study the family of irreducible curves with \\delta nodes belonging to a free linear system |C| with smooth general member on a surface S such that |K_S| is ample. Under the assumption that C is numerically equivalent to pK_S, p\\ge 3 rational, we give an upper bound on \\delta ensuring that the family is smooth of codimension \\delta in |C| (plus another slightly different result of the same type). We give examples showing that the bound is sharp. Some related results concerning linear normality of nodal curves are proved.
9. The Imperative for Improved Global Economic Coordination
OpenAIRE
Stiglitz, Joseph E.
2009-01-01
While global coordination is absolutely essential, success in achieving it may prove difficult because economic globalization has outpaced political globalization. If we are to succeed, we will have to manage coordination better than we have in the past.
10. Tunable Weyl Semimetals in Periodically Driven Nodal Line Semimetals
CERN Document Server
Yan, Zhongbo
2016-01-01
Weyl semimetals and nodal line semimetals are characterized by linear band-touching at nodal points and lines, respectively. We predict that a circularly polarized light drives nodal line semimetals into Weyl semimetals. The Weyl points of the Floquet Weyl semimetal thus obtained are tunable by the incident light, which enables investigations of them in a highly controllable manner. The transition from nodal line semimetals to Weyl semimetals is accompanied by the emergence of a large and tunable anomalous Hall conductivity. Our predictions are experimentally testable in thin films of topological semimetals by either pump-probe ARPES or transport measurement.
11. New Anti-Nodal Monoclonal Antibodies Targeting the Nodal Pre-Helix Loop Involved in Cripto-1 Binding
Directory of Open Access Journals (Sweden)
Annalia Focà
2015-09-01
Full Text Available Nodal is a potent embryonic morphogen belonging to the TGF-β superfamily. Typically, it also binds to the ALK4/ActRIIB receptor complex in the presence of the co-receptor Cripto-1. Nodal expression is physiologically restricted to embryonic tissues and human embryonic stem cells, is absent in normal cells but re-emerges in several human cancers, including melanoma, breast, and colon cancer. Our aim was to obtain mAbs able to recognize Nodal on a major CBR (Cripto-Binding-Region site and to block the Cripto-1-mediated signalling. To achieve this, antibodies were raised against hNodal(44–67 and mAbs generated by the hybridoma technology. We have selected one mAb, named 3D1, which strongly associates with full-length rhNodal (KD 1.4 nM and recognizes the endogenous protein in a panel of human melanoma cell lines by western blot and FACS analyses. 3D1 inhibits the Nodal-Cripto-1 binding and blocks Smad2/3 phosphorylation. Data suggest that inhibition of the Nodal-Cripto-1 axis is a valid therapeutic approach against melanoma and 3D1 is a promising and interesting agent for blocking Nodal-Cripto mediated tumor development. These findings increase the interest for Nodal as both a diagnostic and prognostic marker and as a potential new target for therapeutic intervention.
International Nuclear Information System (INIS)
13. Calibration with Absolute Shrinkage
DEFF Research Database (Denmark)
Øjelund, Henrik; Madsen, Henrik; Thyregod, Poul
2001-01-01
In this paper, penalized regression using the L-1 norm on the estimated parameters is proposed for chemometric je calibration. The algorithm is of the lasso type, introduced by Tibshirani in 1996 as a linear regression method with bound on the absolute length of the parameters, but a modification...
14. FEATURES OF BILATERAL BREAST CANCER NODAL METASTASIS
Directory of Open Access Journals (Sweden)
Ye. A. Fesik
2014-01-01
Full Text Available This article focuses on issues related to the identification and investigation of the lymph node metastases with bilateral breast cancer. The presence of metastases in the lymph nodes determines the stage of the disease, and introducing a form of tumor progression, characterizes the course and prognosis for the future in a specific patient. Thus, the identification of possible morphological and immunohistochemical characteristics of the tumor tissue and their comparison with the frequency and severity of regional lymph nodes would help to solve the problem of the identification of prognostic factors and markers associated with the risk of nodal metastasis in bilateral breast cancer. This work is relevant due to the fact that the literature on this issue to date are treated ambiguously, and answers to many questions, unfortunately, no.The authors performed a morphological study of the tumor tissue from 600 patients suffering from unilateral and bilateral breast cancer. To avoid false results were studied only cases corresponding to the histological type of invasive carcinoma of non-specific type. The study found that a greater number and a greater percentage of the affected lymph node metastases were observed in patients with bilaterally synchronous tumors. The patients of this group of metastatic lymph nodes was detected more frequently in the presence of infiltrative component of three or more types of structures with the presence of these discrete groups of tumor cells, and the observed maximum degree of inflammatory infiltration of the tumor stroma. In the group of patients with unilateral breast cancer nodal metastasis often detects when triple negative molecular genetic type of the lesion, with large amounts of tumor site, in the presence of infiltrative component of three or more types of structures with the obligatory presence of these microalveolar structures and discretely spaced groups of tumor cells and the highest severity of
15. A nodalization study of steam separator in real time simulation
International Nuclear Information System (INIS)
The motive of this paper is to investigate the influence of steam separator nodalization on reactor thermohydraulics in terms of stability and level response. Three different nodalizations of steam separator are studied by using THEATRE and REMARK Code in a BWR simulator. The first nodalization is the traditional one with two nodes for steam separator. In this nodalization, the steam separation is modeled in the outer node, i.e., upper downcomer. Separated steam enters the Steen dome node and the liquid goes to the feedwater node. The second nodalization is similar to the first one with the steam separation modeled in the inner node. There is one additional junction connecting steam dome node and the inner node. The liquid fallback junction connects the inner node and feedwater node. The third nodalization is a combination of the former two with an integrated node for steam separator. Boundary conditions in this study are provided by a simplified feedwater and main steam driver. For comparison purpose, three tests including full power steady state initialisation, recirculation pumps runback and reactor scram are conducted. Major parameters such as reactor pressure, reactor level, void fractions, neutronic power and junction flows are recorded for analysis. Test results clearly show that the first nodalization is stable for steady state initialisation. However it has too responsive level performance in core flow reduction transients. The second nodalization is the closest representation of real plant structure, but not the performance. Test results show that an instability occurs in the separator region for both steady state initialisation and transients. This instability is caused by an unbalanced momentum in the dual loop configuration. The magnitude of the oscillation reduces as the power decreases. No superiority to the other nodalizations is shown in the test results. The third nodalization shows both stability and responsiveness in the tests. (author)
16. Topological surface states in nodal superconductors.
Science.gov (United States)
Schnyder, Andreas P; Brydon, Philip M R
2015-06-24
Topological superconductors have become a subject of intense research due to their potential use for technical applications in device fabrication and quantum information. Besides fully gapped superconductors, unconventional superconductors with point or line nodes in their order parameter can also exhibit nontrivial topological characteristics. This article reviews recent progress in the theoretical understanding of nodal topological superconductors, with a focus on Weyl and noncentrosymmetric superconductors and their protected surface states. Using selected examples, we review the bulk topological properties of these systems, study different types of topological surface states, and examine their unusual properties. Furthermore, we survey some candidate materials for topological superconductivity and discuss different experimental signatures of topological surface states. PMID:26000466
17. Developing a novel nodal grading system to standardize nodal classification in gastric cancer patients with limited lymph node resection
Institute of Scientific and Technical Information of China (English)
2015-01-01
Objective:To develop an easy applicable novel nodal grading system to improve the standardization of nodal classification in patients with limited lymphadenectomy. Methods: We formulated a new approach of nodal classification to classify this category of patients. Log-rank test was used for univariate analysis and Cox proportional hazards model was used for univariate and multivariate analysis. We used linear trendχ2 tests, likelihood ratioχ2 test and Akaike information criterion (AIC) value to assess the homogeneity, discriminatory ability and monotonicity of gradients of the two nodal staging systems.Results:Statistical analysis supported that both the hypothesized N’ stage and hypothesized TN’M stage outperforms the present AJCC/UICC staging system.Conclusion:We developed an easy applicable and reproducible novel nodal grading system that has a greater predicting value than the current AJCC/UICC staging system to classify gastric cancer patients with limited lymphadenectomy.
18. Development of advanced nodal diffusion methods for modern computer architectures
International Nuclear Information System (INIS)
A family of highly efficient multidimensional multigroup advanced neutron-diffusion nodal methods, ILLICO, were implemented on sequential, vector, and vector-concurrent computers. Three-dimensional realistic benchmark problems can be solved in vectorized mode in less than 0.73 s (33.86 Mflops) on a Cray X-MP/48. Vector-concurrent implementations yield speedups as high as 9.19 on an Alliant FX/8. These results show that the ILLICO method preserves essentially all of its speed advantage over finite-difference methods. A self-consistent higher-order nodal diffusion method was developed and implemented. Nodal methods for global nuclear reactor multigroup diffusion calculations which account explicitly for heterogeneities in the assembly nuclear properties were developed and evaluated. A systematic analysis of the zero-order variable cross section nodal method was conducted. Analyzing the KWU PWR depletion benchmark problem, it is shown that when burnup heterogeneities arise, ordinary nodal methods, which do not explicitly treat the heterogeneities, suffer a significant systematic error that accumulates. A nodal method that treats explicitly the space dependence of diffusion coefficients was developed and implemented. A consistent burnup-correction method for nodal microscopic depletion analysis was developed
19. Embryonic morphogen nodal promotes breast cancer growth and progression.
Directory of Open Access Journals (Sweden)
Daniela F Quail
Full Text Available Breast cancers expressing human embryonic stem cell (hESC-associated genes are more likely to progress than well-differentiated cancers and are thus associated with poor patient prognosis. Elevated proliferation and evasion of growth control are similarly associated with disease progression, and are classical hallmarks of cancer. In the current study we demonstrate that the hESC-associated factor Nodal promotes breast cancer growth. Specifically, we show that Nodal is elevated in aggressive MDA-MB-231, MDA-MB-468 and Hs578t human breast cancer cell lines, compared to poorly aggressive MCF-7 and T47D breast cancer cell lines. Nodal knockdown in aggressive breast cancer cells via shRNA reduces tumour incidence and significantly blunts tumour growth at primary sites. In vitro, using Trypan Blue exclusion assays, Western blot analysis of phosphorylated histone H3 and cleaved caspase-9, and real time RT-PCR analysis of BAX and BCL2 gene expression, we demonstrate that Nodal promotes expansion of breast cancer cells, likely via a combinatorial mechanism involving increased proliferation and decreased apopotosis. In an experimental model of metastasis using beta-glucuronidase (GUSB-deficient NOD/SCID/mucopolysaccharidosis type VII (MPSVII mice, we show that although Nodal is not required for the formation of small (<100 cells micrometastases at secondary sites, it supports an elevated proliferation:apoptosis ratio (Ki67:TUNEL in micrometastatic lesions. Indeed, at longer time points (8 weeks, we determined that Nodal is necessary for the subsequent development of macrometastatic lesions. Our findings demonstrate that Nodal supports tumour growth at primary and secondary sites by increasing the ratio of proliferation:apoptosis in breast cancer cells. As Nodal expression is relatively limited to embryonic systems and cancer, this study establishes Nodal as a potential tumour-specific target for the treatment of breast cancer.
20. Tunable Weyl Points in Periodically Driven Nodal Line Semimetals
Science.gov (United States)
Yan, Zhongbo; Wang, Zhong
2016-08-01
Weyl semimetals and nodal line semimetals are characterized by linear band touching at zero-dimensional points and one-dimensional lines, respectively. We predict that a circularly polarized light drives nodal line semimetals into Weyl semimetals. The Floquet Weyl points thus obtained are tunable by the incident light, which enables investigations of them in a highly controllable manner. The transition from nodal line semimetals to Weyl semimetals is accompanied by the emergence of a large and tunable anomalous Hall conductivity. Our predictions are experimentally testable by transport measurement in film samples or by pump-probe angle-resolved photoemission spectroscopy.
1. ABSOLUTE POLARIMETRY AT RHIC.
Energy Technology Data Exchange (ETDEWEB)
OKADA; BRAVAR, A.; BUNCE, G.; GILL, R.; HUANG, H.; MAKDISI, Y.; NASS, A.; WOOD, J.; ZELENSKI, Z.; ET AL.
2007-09-10
Precise and absolute beam polarization measurements are critical for the RHIC spin physics program. Because all experimental spin-dependent results are normalized by beam polarization, the normalization uncertainty contributes directly to final physics uncertainties. We aimed to perform the beam polarization measurement to an accuracy Of {Delta}P{sub beam}/P{sub beam} < 5%. The absolute polarimeter consists of Polarized Atomic Hydrogen Gas Jet Target and left-right pairs of silicon strip detectors and was installed in the RHIC-ring in 2004. This system features proton-proton elastic scattering in the Coulomb nuclear interference (CNI) region. Precise measurements of the analyzing power A{sub N} of this process has allowed us to achieve {Delta}P{sub beam}/P{sub beam} = 4.2% in 2005 for the first long spin-physics run. In this report, we describe the entire set up and performance of the system. The procedure of beam polarization measurement and analysis results from 2004-2005 are described. Physics topics of AN in the CNI region (four-momentum transfer squared 0.001 < -t < 0.032 (GeV/c){sup 2}) are also discussed. We point out the current issues and expected optimum accuracy in 2006 and the future.
2. Absolute polarimetry at RHIC
CERN Document Server
Okada, H; Bravar, A; Bunce, G; Dhawan, S; Eyser, K O; Gill, R; Haeberli, W; Huang, H; Jinnouchi, O; Makdisi, Y; Nakagawa, I; Nass, A; Saitô, N; Stephenson, E; Sviridia, D; Wise, T; Wood, J; Zelenski, A
2007-01-01
Precise and absolute beam polarization measurements are critical for the RHIC spin physics program. Because all experimental spin-dependent results are normalized by beam polarization, the normalization uncertainty contributes directly to final physics uncertainties. We aimed to perform the beam polarization measurement to an accuracy of $\\Delta P_{beam}/P_{beam} < 5%$. The absolute polarimeter consists of Polarized Atomic Hydrogen Gas Jet Target and left-right pairs of silicon strip detectors and was installed in the RHIC-ring in 2004. This system features \\textit{proton-proton} elastic scattering in the Coulomb nuclear interference (CNI) region. Precise measurements of the analyzing power $A_N$ of this process has allowed us to achieve $\\Delta P_{beam}/P_{beam} =4.2%$ in 2005 for the first long spin-physics run. In this report, we describe the entire set up and performance of the system. The procedure of beam polarization measurement and analysis results from 2004-2005 are described. Physics topics of $A... 3. Absolute Baseline for Testing of Electronic Distance Meters OpenAIRE Jaroslav Braun; Filip Dvořáček; Martin Štroner 2014-01-01 The paper deals with the construction and determination of coordinates of the absoluteEDMs baseline in a laboratory with 16 pillars with forced centring. Leica Absolute TrackerAT401 (standard deviation of distance measurement: 5 μ m, standard deviation of anglemeasurement: 0.15 mgon), which is designed for very accurate industrial measurements,was used for our purpose. Lengths between the baseline points were determined with astandard deviation of 0.02 mm. The baseline is used for determining... 4. Present Status of GNF New Nodal Simulator International Nuclear Information System (INIS) This paper presents core simulator consolidation work done at Global Nuclear Fuel (GNF). The unified simulator needs to supercede the capabilities of past simulator packages from the original GNF partners: GE, Hitachi, and Toshiba. At the same time, an effort is being made to produce a simulation package that will be a state-of-the-art analysis tool when released, in terms of the physics solution methodology and functionality. The core simulator will be capable and qualified for (a) high-energy cycles in the U.S. markets, (b) mixed-oxide (MOX) introduction in Japan, and (c) high-power density plants in Europe, etc. The unification of the lattice physics code is also in progress based on a transport model with collision probability methods. The AETNA core simulator is built upon the PANAC11 software base. The goal is to essentially replace the 1.5-energy-group model with a higher-order multigroup nonlinear nodal solution capable of the required modeling fidelity, while keeping highly automated library generation as well as functionality. All required interfaces to PANAC11 will be preserved, which minimizes the impact on users and process automation. Preliminary results show statistical accuracy improvement over the 1.5-group model 5. BEACON: An application of nodal methods for operational support International Nuclear Information System (INIS) A practical application of nodal methods is on-line plant operational support. However, to enable plant personnel to take full advantage of a nodal model to support plant operations, (a) a core nodal model must always be up to date with the current core history and conditions, (b) the nodal methods must be fast enough to allow numerous core calculations to be performed in minutes to support engineering decisions, and (c) the system must be easily accessible to engineering personnel at the reactor, their offices, or any other location considered appropriate. A core operational support package developed by Westinghouse called BEACON (best estimate analysis of core operations - nuclear) has been installed at several plants. Results from these plants and numerous in-core flux maps analyzed have demonstrated the accuracy of the model and the effectiveness of the methodology 6. Nodal the second life of the accelerator control language CERN Document Server Cuisinier, G; Ribeiro, P; Kagarmanov, A; Kovaltsov, V I 1993-01-01 Nodal is a popular interpreter language for accelerator controls since the beginning of the 70's. Nodal has been rewritten in the C language to be easily portable to the different computer platforms which are in use in today's accelerator controls. The paper describes the major features of this new version of Nodal, the major software packages which are available through this implementation, the platforms on which it is currently running, and some relevant performances.The paper presents the major domains of usage of Nodal and its capability for these classes of applications. The experience gained during the rejuvenation project of the CERN accelerator control systems is presented. The benefit of this use is discussed, in particular with a view to the prevailing strong constraints in personnel and money resources. 7. Rotational total skin and total nodal radiotherapy in mycosis fungoides Energy Technology Data Exchange (ETDEWEB) Bamberg, M.; Molls, M.; Langrock, J.; Muskalla, K.; Quast, U. 1987-04-01 The following report describes our technique of rotational total skin radiotherapy with electrons (TSER). We present stage related treatment results. Furthermore our first experiences with the combination of TSER and total nodal irradiation (TNI) are communicated. 8. Optical tweezers absolute calibration CERN Document Server Dutra, R S; Neto, P A Maia; Nussenzveig, H M 2014-01-01 Optical tweezers are highly versatile laser traps for neutral microparticles, with fundamental applications in physics and in single molecule cell biology. Force measurements are performed by converting the stiffness response to displacement of trapped transparent microspheres, employed as force transducers. Usually, calibration is indirect, by comparison with fluid drag forces. This can lead to discrepancies by sizable factors. Progress achieved in a program aiming at absolute calibration, conducted over the past fifteen years, is briefly reviewed. Here we overcome its last major obstacle, a theoretical overestimation of the peak stiffness, within the most employed range for applications, and we perform experimental validation. The discrepancy is traced to the effect of primary aberrations of the optical system, which are now included in the theory. All required experimental parameters are readily accessible. Astigmatism, the dominant effect, is measured by analyzing reflected images of the focused laser spo... 9. Torsionfree Sheaves over a Nodal Curve of Arithmetic Genus One Indian Academy of Sciences (India) Usha N Bhosle; Indranil Biswas 2008-02-01 We classify all isomorphism classes of stable torsionfree sheaves on an irreducible nodal curve of arithmetic genus one defined over$\\mathbb{C}$. Let be a nodal curve of arithmetic genus one defined over$\\mathbb{R}$, with exactly one node, such that does not have any real points apart from the node. We classify all isomorphism classes of stable real algebraic torsionfree sheaves over of even rank. We also classify all isomorphism classes of real algebraic torsionfree sheaves over of rank one. 10. Estimating Absolute Site Effects Energy Technology Data Exchange (ETDEWEB) Malagnini, L; Mayeda, K M; Akinci, A; Bragato, P L 2004-07-15 The authors use previously determined direct-wave attenuation functions as well as stable, coda-derived source excitation spectra to isolate the absolute S-wave site effect for the horizontal and vertical components of weak ground motion. They used selected stations in the seismic network of the eastern Alps, and find the following: (1) all ''hard rock'' sites exhibited deamplification phenomena due to absorption at frequencies ranging between 0.5 and 12 Hz (the available bandwidth), on both the horizontal and vertical components; (2) ''hard rock'' site transfer functions showed large variability at high-frequency; (3) vertical-motion site transfer functions show strong frequency-dependence, and (4) H/V spectral ratios do not reproduce the characteristics of the true horizontal site transfer functions; (5) traditional, relative site terms obtained by using reference ''rock sites'' can be misleading in inferring the behaviors of true site transfer functions, since most rock sites have non-flat responses due to shallow heterogeneities resulting from varying degrees of weathering. They also use their stable source spectra to estimate total radiated seismic energy and compare against previous results. they find that the earthquakes in this region exhibit non-constant dynamic stress drop scaling which gives further support for a fundamental difference in rupture dynamics between small and large earthquakes. To correct the vertical and horizontal S-wave spectra for attenuation, they used detailed regional attenuation functions derived by Malagnini et al. (2002) who determined frequency-dependent geometrical spreading and Q for the region. These corrections account for the gross path effects (i.e., all distance-dependent effects), although the source and site effects are still present in the distance-corrected spectra. The main goal of this study is to isolate the absolute site effect (as a function of frequency 11. Be Resolute about Absolute Value Science.gov (United States) Kidd, Margaret L. 2007-01-01 This article explores how conceptualization of absolute value can start long before it is introduced. The manner in which absolute value is introduced to students in middle school has far-reaching consequences for their future mathematical understanding. It begins to lay the foundation for students' understanding of algebra, which can change… 12. A computational study of nodal-based tetrahedral element behavior. Energy Technology Data Exchange (ETDEWEB) Gullerud, Arne S. 2010-09-01 This report explores the behavior of nodal-based tetrahedral elements on six sample problems, and compares their solution to that of a corresponding hexahedral mesh. The problems demonstrate that while certain aspects of the solution field for the nodal-based tetrahedrons provide good quality results, the pressure field tends to be of poor quality. Results appear to be strongly affected by the connectivity of the tetrahedral elements. Simulations that rely on the pressure field, such as those which use material models that are dependent on the pressure (e.g. equation-of-state models), can generate erroneous results. Remeshing can also be strongly affected by these issues. The nodal-based test elements as they currently stand need to be used with caution to ensure that their numerical deficiencies do not adversely affect critical values of interest. 13. Simulating Weyl points and nodal loops in an optical superlattice Science.gov (United States) Zhang, Dan-Wei 2016-08-01 We propose a scheme to simulate Weyl points and nodal loops with ultracold atoms in an optical lattice that is subjected to realizable synthetic magnetic field and synthetic dimension. We show that a Hofstadter-like Hamiltonian with a cyclically parameterized on-site energy term can be realized in a tunable two-dimensional optical superlattice, based on the laser-assisted atomic tunneling method. This model effectively describes a three-dimensional periodic lattice system under magnetic fluxes, where a synthetic dimension is encoded by a cyclical phase of the optical lattice potential. For different atomic hopping configurations, the single-particle bands are demonstrated to, respectively, exhibit Weyl points and nodal loops in the extended three-dimensional Brillouin zone. Furthermore, we illustrate that the mimicked Weyl points and nodal loops can be experimentally detected by measuring the atomic transfer fraction in Bloch-Zener oscillations. 14. HEXPEDITE: A net current multigroup nodal diffusion method for hexagonal-z geometry International Nuclear Information System (INIS) The feasibility of a nodal diffusion algorithm for hexagonal cores was first demonstrated by Duracz and by Lawrence. They implemented a polynomial method with partial currents for internode coupling. Following them, several authors introduced variants of the expansion technique. Wagner developed an analytical method; however, like all previous authors, he still used partial currents for internode coupling and a response matrix solution approach. Very recently, another polynomial model with net currents expressed in terms of transverse-integrated fluxes and a nodal integral method based on coordinate transformations were presented. A transformation-group method was also introduced. In this paper, a hexagonal-z method similar in approach to that of the Cartesian geometry ILLICO is presented. The new method uses an analytical solution of the transverse-integrated equations, net currents for internode coupling, and a global coupling solution scheme different from that of the methods discussed earlier. An extension that treats explicitly the in-node spatial dependence of cross sections is also introduced 15. Development and validation of a nodal code for core calculation International Nuclear Information System (INIS) The code RHENO solves the multigroup three-dimensional diffusion equation using a nodal method of polynomial expansion.A comparative study has been made between this code and present internationals nodal diffusion codes, resulting that the RHENO is up to date.The RHENO has been integrated to a calculation line and has been extend to make burnup calculations.Two methods for pin power reconstruction were developed: modulation and imbedded. The modulation method has been implemented in a program, while the implementation of the imbedded method will be concluded shortly.The validation carried out (that includes experimental data of a MPR) show very good results and calculation efficiency 16. Oddness of least energy nodal solutions on radial domains Directory of Open Access Journals (Sweden) Christopher Grumiau 2010-07-01 Full Text Available In this article, we consider the Lane-Emden problem $$displaylines{ Delta u(x + |{u(x}mathclose|^{p-2}u(x=0, quad hbox{for } xinOmega,cr u(x=0, quad hbox{for } xinpartialOmega, }$$ where$2 < p < 2^{*}$and$Omega$is a ball or an annulus in$mathbb{R}^{N}$,$Ngeq 2. We show that, for p close to 2, least energy nodal solutions are odd with respect to an hyperplane -- which is their nodal surface. The proof ingredients are a constrained implicit function theorem and the fact that the second eigenvalue is simple up to rotations. 17. ROE Absolute Sea Level Changes Data.gov (United States) U.S. Environmental Protection Agency — This raster dataset represents changes in absolute sea level along U.S. coasts from 1993 to 2014. Data were provided by the University of Colorado at Boulder (2015)... 18. Note on the nodal line of the p-Laplacian Directory of Open Access Journals (Sweden) Abdel R. El Amrouss 2006-09-01 Full Text Available In this paper, we prove that the length of the nodal line of the eigenfunctions associated to the second eigenvalue of the problem $$-Delta_p u = lambda ho (x |u|^{p-2}u quad hbox{in } Omega$$ with the Dirichlet conditions is not bounded uniformly with respect to the weight. 19. The Nodal Location of Metastases in Melanoma Sentinel Lymph Nodes DEFF Research Database (Denmark) Riber-Hansen, Rikke; Nyengaard, Jens; Hamilton-Dutoit, Stephen; 2009-01-01 BACKGROUND: The design of melanoma sentinel lymph node (SLN) histologic protocols is based on the premise that most metastases are found in the central parts of the nodes, but the evidence for this belief has never been thoroughly tested. METHODS: The nodal location of melanoma metastases in 149... 20. Tbx6 regulates left/right patterning in mouse embryos through effects on nodal cilia and perinodal signaling. Directory of Open Access Journals (Sweden) Anna-Katerina Hadjantonakis Full Text Available BACKGROUND: The determination of left/right body axis during early embryogenesis sets up a developmental cascade that coordinates the development of the viscera and is essential to the correct placement and alignment of organ systems and vasculature. Defective left-right patterning can lead to congenital cardiac malformations, vascular anomalies and other serious health problems. Here we describe a novel role for the T-box transcription factor gene Tbx6 in left/right body axis determination in the mouse. RESULTS: Embryos lacking Tbx6 show randomized embryo turning and heart looping. Our results point to multiple mechanisms for this effect. First, Dll1, a direct target of Tbx6, is down regulated around the node in Tbx6 mutants and there is a subsequent decrease in nodal signaling, which is required for laterality determination. Secondly, in spite of a lack of expression of Tbx6 in the node, we document a profound effect of the Tbx6 mutation on the morphology and motility of nodal cilia. This results in the loss of asymmetric calcium signaling at the periphery of the node, suggesting that unidirectional nodal flow is disrupted. To carry out these studies, we devised a novel method for direct labeling and live imaging cilia in vivo using a genetically-encoded fluorescent protein fusion that labels tubulin, combined with laser point scanning confocal microscopy for direct visualization of cilia movement. CONCLUSIONS: We conclude that the transcription factor gene Tbx6 is essential for correct left/right axis determination in the mouse and acts through effects on notch signaling around the node as well as through an effect on the morphology and motility of the nodal cilia. 1. Diffusion Monte Carlo in internal coordinates. Science.gov (United States) Petit, Andrew S; McCoy, Anne B 2013-08-15 An internal coordinate extension of diffusion Monte Carlo (DMC) is described as a first step toward a generalized reduced-dimensional DMC approach. The method places no constraints on the choice of internal coordinates other than the requirement that they all be independent. Using H(3)(+) and its isotopologues as model systems, the methodology is shown to be capable of successfully describing the ground state properties of molecules that undergo large amplitude, zero-point vibrational motions. Combining the approach developed here with the fixed-node approximation allows vibrationally excited states to be treated. Analysis of the ground state probability distribution is shown to provide important insights into the set of internal coordinates that are less strongly coupled and therefore more suitable for use as the nodal coordinates for the fixed-node DMC calculations. In particular, the curvilinear normal mode coordinates are found to provide reasonable nodal surfaces for the fundamentals of H(2)D(+) and D(2)H(+) despite both molecules being highly fluxional. 2. Absolute Baseline for Testing of Electronic Distance Meters Directory of Open Access Journals (Sweden) Jaroslav Braun 2014-06-01 Full Text Available The paper deals with the construction and determination of coordinates of the absoluteEDMs baseline in a laboratory with 16 pillars with forced centring. Leica Absolute TrackerAT401 (standard deviation of distance measurement: 5 μ m, standard deviation of anglemeasurement: 0.15 mgon, which is designed for very accurate industrial measurements,was used for our purpose. Lengths between the baseline points were determined with astandard deviation of 0.02 mm. The baseline is used for determining systematic and randomerrors of distance meters and for accuracy of distance meters at short distances commonin engineering surveying for purposes of mechanical engineering. 3. MAGSAT: Vector magnetometer absolute sensor alignment determination Science.gov (United States) Acuna, M. H. 1981-01-01 A procedure is described for accurately determining the absolute alignment of the magnetic axes of a triaxial magnetometer sensor with respect to an external, fixed, reference coordinate system. The method does not require that the magnetic field vector orientation, as generated by a triaxial calibration coil system, be known to better than a few degrees from its true position, and minimizes the number of positions through which a sensor assembly must be rotated to obtain a solution. Computer simulations show that accuracies of better than 0.4 seconds of arc can be achieved under typical test conditions associated with existing magnetic test facilities. The basic approach is similar in nature to that presented by McPherron and Snare (1978) except that only three sensor positions are required and the system of equations to be solved is considerably simplified. Applications of the method to the case of the MAGSAT Vector Magnetometer are presented and the problems encountered discussed. 4. Wave pinning and spatial patterning in a mathematical model of Antivin/Lefty-Nodal signalling. Science.gov (United States) Middleton, A M; King, J R; Loose, M 2013-12-01 Nodal signals are key regulators of mesoderm and endoderm development in vertebrate embryos. It has been observed experimentally that in Xenopus embryos the spatial range of Nodal signals is restricted by the signal Antivin (also known as Lefty). Nodal signals can activate both Nodal and Antivin, whereas Antivin is thought to antagonise Nodal by binding either directly to it or to its receptor. In this paper we develop a mathematical model of this signalling network in a line of cells. We consider the heterodimer and receptor-mediated inhibition mechanisms separately and find that, in both cases, the restriction by Antivin to the range of Nodal signals corresponds to wave pinning in the model. Our analysis indicates that, provided Antivin diffuses faster than Nodal, either mechanism can robustly account for the experimental data. We argue that, in the case of Xenopus development, it is wave pinning, rather than Turing-type patterning, that is underlying Nodal-Antivin dynamics. This leads to several experimentally testable predictions, which are discussed. Furthermore, for heterodimer-mediated inhibition to prevent waves of Nodal expression from propagating, the Nodal-Antivin complex must be turned over, and diffusivity of the complex must be negligible. In the absence of molecular mechanisms regulating these, we suggest that Antivin restricts Nodal signals via receptor-mediated, and not heterodimer-mediated, inhibition. PMID:23070212 5. Off-diagonal Jacobian support for Nodal BCs Energy Technology Data Exchange (ETDEWEB) Peterson, John W. [Idaho National Lab. (INL), Idaho Falls, ID (United States); Andrs, David [Idaho National Lab. (INL), Idaho Falls, ID (United States); Gaston, Derek R. [Idaho National Lab. (INL), Idaho Falls, ID (United States); Permann, Cody J. [Idaho National Lab. (INL), Idaho Falls, ID (United States); Slaughter, Andrew E. [Idaho National Lab. (INL), Idaho Falls, ID (United States) 2015-01-01 In this brief note, we describe the implementation of o-diagonal Jacobian computations for nodal boundary conditions in the Multiphysics Object Oriented Simulation Environment (MOOSE) [1] framework. There are presently a number of applications [2{5] based on the MOOSE framework that solve complicated physical systems of partial dierential equations whose boundary conditions are often highly nonlinear. Accurately computing the on- and o-diagonal Jacobian and preconditioner entries associated to these constraints is crucial for enabling ecient numerical solvers in these applications. Two key ingredients are required for properly specifying the Jacobian contributions of nonlinear nodal boundary conditions in MOOSE and nite element codes in general: 1. The ability to zero out entire Jacobian matrix rows after \ 6. Nodal failure index approach to groundwater remediation design Science.gov (United States) Lee, J.; Reeves, H.W.; Dowding, C.H. 2008-01-01 Computer simulations often are used to design and to optimize groundwater remediation systems. We present a new computationally efficient approach that calculates the reliability of remedial design at every location in a model domain with a single simulation. The estimated reliability and other model information are used to select a best remedial option for given site conditions, conceptual model, and available data. To evaluate design performance, we introduce the nodal failure index (NFI) to determine the number of nodal locations at which the probability of success is below the design requirement. The strength of the NFI approach is that selected areas of interest can be specified for analysis and the best remedial design determined for this target region. An example application of the NFI approach using a hypothetical model shows how the spatial distribution of reliability can be used for a decision support system in groundwater remediation design. ?? 2008 ASCE. 7. HEXAN - a hexagonal nodal code for solving the diffusion equation International Nuclear Information System (INIS) This report describes the theory of and provides a user's manual for the HEXAN program, which is a nodal program for the solution of the few-group diffusion equation in hexagonal geometry. Based upon symmetry considerations, the theory provides an analytical solution in a homogeneous node. WWER and HTGR test problem solutions are presented. The equivalence of the finite-difference scheme and the response matrix method is proven. The properties of a symmetric node's response matrix are investigated. (author) 8. Nodal equivalence theory for hexagonal geometry, thermal reactor analysis International Nuclear Information System (INIS) An important aspect of advanced nodal methods is the determination of equivalent few-group parameters for the relatively large homogenized regions used in the nodal flux solution. The theoretical foundation for light water reactor (LWR) assembly homogenization methods has been clearly established, and during the last several years, its successes have secured its position in the stable of dependable LWR analysis methods. Groupwise discontinuity factors that correct for assembly homogenization errors are routinely generated along with the group constants during lattice physics analysis. During the last several years, there has been interest in applying equivalence theory to other reactor types and other geometries. A notable effort has been the work at Argonne National Laboratory to incorporate nodal equivalence theory (NET) for hexagonal lattices into the nodal diffusion option of the DIF3D code. This work was originally intended to improve the neutronics methods used for the analysis of the Experimental Breeder Reactor II (EBR-II), and Ref. 4 discusses the success of that application. More recently, however, attempts were made to apply NET to advanced, thermal reactor designs such as the modular high-temperature gas reactor (MHTGR) and the new production heavy water reactor (NPR/HWR). The same methods that were successful for EBR-II have encountered problems for these reactors. Our preliminary analysis indicates that the sharp global flux gradients in these cores requires large discontinuity factors (greater than 4 or 5) to reproduce the reference solution. This disrupts the convergence of the iterative methods used to solve for the node-wise flux moments and partial currents. Several attempts to remedy the problem have been made over the last few years, including bounding the discontinuity factors and providing improved initial guesses for the flux solution, but nothing has been satisfactory 9. Concomitant nodal involvement by Langerhans cell histiocytosis and Hodgkin's lymphoma. Science.gov (United States) Geurten, Claire; Thiry, Albert; Jamblin, Paul; Demarche, Martine; Hoyoux, Claire 2015-12-01 A 10-year-old girl with a family history of Hodgkin's lymphoma presented with a 2 month history of cervical lymphadenopathy and weight loss. Biopsy indicated concomitant nodal involvement by Langerhans cell histiocytosis and Hodgkin's lymphoma. Such an association is rare, especially so in children, but is not an isolated phenomenon, thereby prompting the question of whether Langerhans cell histiocytosis is a reactive or a neoplastic process. PMID:26556799 10. Absolute transition probabilities of phosphorus. Science.gov (United States) Miller, M. H.; Roig, R. A.; Bengtson, R. D. 1971-01-01 Use of a gas-driven shock tube to measure the absolute strengths of 21 P I lines and 126 P II lines (from 3300 to 6900 A). Accuracy for prominent, isolated neutral and ionic lines is estimated to be 28 to 40% and 18 to 30%, respectively. The data and the corresponding theoretical predictions are examined for conformity with the sum rules.- 11. Absolute luminosity measurements at LHCb CERN Document Server Hopchev, Plamen 2011-01-01 Absolute luminosity measurements are of general interest for colliding-beam experiments at storage rings. These measurements are necessary to determine the absolute cross-sections of reaction processes and are valuable to quantify the performance of the accelerator. LHCb has applied two methods to determine the absolute scale of its luminosity measurements for proton-proton collisions at the LHC running at a centre-of-mass energy of 7 TeV. In addition to the classic van der Meer'' scan method a novel technique has been developed which makes use of direct imaging of the individual beams using both proton-gas and proton-proton interactions. The beam imaging method is made possible by the high resolution of the LHCb vertex detector and the close proximity of the detector to the beams, and allows beam parameters such as positions, angles and widths to be determined. We describe both methods and compare the two results. In addition, we present the techniques used to transport the absolute luminosity measurement ... 12. LSST Telescope Alignment Plan Based on Nodal Aberration Theory Science.gov (United States) Sebag, J.; Gressler, W.; Schmid, T.; Rolland, J. P.; Thompson, K. P. 2012-04-01 The optical alignment of the Large Synoptic Survey Telescope (LSST) is potentially challenging, due to its fast three-mirror optical design and its large 3.5° field of view (FOV). It is highly advantageous to align the three-mirror optical system prior to the integration of the complex science camera on the telescope, which corrects the FOV via three refractive elements and includes the operational wavefront sensors. A telescope alignment method based on nodal aberration theory (NAT) is presented here to address this challenge. Without the science camera installed on the telescope, the on-axis imaging performance of the telescope is diffraction-limited, but the field of view is not corrected. The nodal properties of the three-mirror telescope design have been analyzed and an alignment approach has been developed using the intrinsically linear nodal behavior, which is linked via sensitivities to the misalignment parameters. Since mirror figure errors will exist in any real application, a methodology to introduce primary-mirror figure errors into the analysis has been developed and is also presented. 13. Radiotherapy studies and extra-nodal non-Hodgkin lymphomas, progress and challenges DEFF Research Database (Denmark) Specht, L 2012-01-01 for the more common extra-nodal organs, e.g. stomach, Waldeyer's ring, skin and brain, are fairly well known and show significant variation. A few randomised trials have been carried out testing the role of radiotherapy in these lymphomas. However, for most extra-nodal lymphomas, randomised trials have...... not been carried out, and treatment decisions are made on small patient series and extrapolations from nodal lymphomas. Hopefully, wide international collaboration will make controlled clinical trials possible in the less common extra-nodal lymphomas. Modern highly conformal radiotherapy allows better...... coverage of extra-nodal lymphomatous involvement with better sparing of normal tissues. The necessary radiation doses and volumes need to be defined for the different extra-nodal lymphoma entities. The challenge is to optimise the use of radiotherapy in the modern multimodality treatment of extra... 14. Elsevier Trophoblast Research Award lecture: The multifaceted role of Nodal signaling during mammalian reproduction. Science.gov (United States) Park, C B; Dufort, D 2011-03-01 Nodal, a secreted signaling protein in the transforming growth factor-beta (TGF-β) superfamily, has established roles in vertebrate development. However, components of the Nodal signaling pathway are also expressed at the maternal-fetal interface and have been implicated in many processes of mammalian reproduction. Emerging evidence indicates that Nodal and its extracellular inhibitor Lefty are expressed in the uterus and complex interactions between the two proteins mediate menstruation, decidualization and embryo implantation. Furthermore, several studies have shown that Nodal from both fetal and maternal sources may regulate trophoblast cell fate and facilitate placentation as both embryonic and uterine-specific Nodal knockout mouse strains exhibit disrupted placenta morphology. Here we review the established and prospective roles of Nodal signaling in facilitating successful pregnancy, including recent evidence supporting a potential link to parturition and preterm birth. PMID:21195476 15. Elsevier Trophoblast Research Award lecture: The multifaceted role of Nodal signaling during mammalian reproduction. Science.gov (United States) Park, C B; Dufort, D 2011-03-01 Nodal, a secreted signaling protein in the transforming growth factor-beta (TGF-β) superfamily, has established roles in vertebrate development. However, components of the Nodal signaling pathway are also expressed at the maternal-fetal interface and have been implicated in many processes of mammalian reproduction. Emerging evidence indicates that Nodal and its extracellular inhibitor Lefty are expressed in the uterus and complex interactions between the two proteins mediate menstruation, decidualization and embryo implantation. Furthermore, several studies have shown that Nodal from both fetal and maternal sources may regulate trophoblast cell fate and facilitate placentation as both embryonic and uterine-specific Nodal knockout mouse strains exhibit disrupted placenta morphology. Here we review the established and prospective roles of Nodal signaling in facilitating successful pregnancy, including recent evidence supporting a potential link to parturition and preterm birth. 16. Poisson Coordinates. Science.gov (United States) Li, Xian-Ying; Hu, Shi-Min 2013-02-01 Harmonic functions are the critical points of a Dirichlet energy functional, the linear projections of conformal maps. They play an important role in computer graphics, particularly for gradient-domain image processing and shape-preserving geometric computation. We propose Poisson coordinates, a novel transfinite interpolation scheme based on the Poisson integral formula, as a rapid way to estimate a harmonic function on a certain domain with desired boundary values. Poisson coordinates are an extension of the Mean Value coordinates (MVCs) which inherit their linear precision, smoothness, and kernel positivity. We give explicit formulas for Poisson coordinates in both continuous and 2D discrete forms. Superior to MVCs, Poisson coordinates are proved to be pseudoharmonic (i.e., they reproduce harmonic functions on n-dimensional balls). Our experimental results show that Poisson coordinates have lower Dirichlet energies than MVCs on a number of typical 2D domains (particularly convex domains). As well as presenting a formula, our approach provides useful insights for further studies on coordinates-based interpolation and fast estimation of harmonic functions. 17. Regulation of the embryonic morphogen Nodal by Notch4 facilitates manifestation of the aggressive melanoma phenotype OpenAIRE Hardy, Katharine M.; Kirschmann, Dawn A; Seftor, Elisabeth A.; Margaryan, Naira v.; Postovit, Lynne-Marie; Strizzi, Luigi; Hendrix, Mary J.C. 2010-01-01 Metastatic melanoma is an aggressive skin cancer associated with poor prognosis. The reactivation of the embryonic morphogen Nodal in metastatic melanoma has previously been shown to regulate the aggressive behavior of these tumor cells. During the establishment of left-right asymmetry in early vertebrate development, Nodal expression is specifically regulated by a Notch signaling pathway. We hypothesize that a similar relationship between Notch and Nodal may be re-established in melanoma. In... 18. Micropropagation of Costus speciosus (Koen. Sm. Using Nodal Segment Culture Directory of Open Access Journals (Sweden) Kshetrimayum PUNYARANI 2010-03-01 Full Text Available Nodal segments of Costus speciosus (Koen. Sm. containing single axillary buds were cultured on Murashige and Skoog medium (MS medium supplemented with plant growth regulators for inducing plantlets. For breaking of axillary bud dormancy, nodal segments were cultured on 40-70gl-1 sucrose or 1-13 �M adenine sulphate (AdS supplemented MS basal medium containing 5 �M 6-benzylaminopurine (BAP and 1�M ?-naphthalene acetic acid (NAA. The nodal segments cultured on 1-13 �M AdS, 5 �M BAP, 1 �M NAA and 50gl-1 sucrose showed simultaneous production of shoots and roots while those cultured on 5 �M BAP, 1 �M NAA and 40-70gl-1 sucrose produced shoots only. The most effective media for breaking axillary bud dormancy was 5 �M BAP, 1 �M NAA, 50 gl-1 sucrose and 10 �M AdS supplemented medium. The propagules from 40-70gl-1 sucrose produced roots in shoot multiplication medium, i.e.,10 �M AdS, 1 �M NAA, 50gl-1 sucrose and 3-11 �M BAP supplemented medium. The best response for shoot multiplication was on 10 �M AdS, 1 �M NAA, 50gl-1 sucrose and 7 �M BAP. The well-rooted shoots were hardened and transferred to the soil where they showed 95% survival rate. Results show that axillary bud can be used for micropropagation of Costus speciosus. 19. Approximate Schur complement preconditioning of the lowest order nodal discretizations Energy Technology Data Exchange (ETDEWEB) Moulton, J.D.; Ascher, U.M. [Univ. of British Columbia, Vancouver, British Columbia (Canada); Morel, J.E. [Los Alamos National Lab., NM (United States) 1996-12-31 Particular classes of nodal methods and mixed hybrid finite element methods lead to equivalent, robust and accurate discretizations of 2nd order elliptic PDEs. However, widespread popularity of these discretizations has been hindered by the awkward linear systems which result. The present work exploits this awkwardness, which provides a natural partitioning of the linear system, by defining two optimal preconditioners based on approximate Schur complements. Central to the optimal performance of these preconditioners is their sparsity structure which is compatible with Dendys black box multigrid code. 20. Nodal wear model: corrosion in carbon blast furnace hearths International Nuclear Information System (INIS) Criteria developed for the Nodal Wear Model (NWM) were applied to estimate the shape of the corrosion profiles that a blast furnace hearth may acquire during its campaign. Taking into account design of the hearth, the boundary conditions, the characteristics of the refractory materials used and the operation conditions of the blast furnace, simulation of wear profiles with central well, mushroom and elephant foot shape were accomplished. The foundations of the NWM are constructed considering that the corrosion of the refractory is a function of the temperature present at each point (node) of the liquid metal-refractory interface and the corresponding physical and chemical characteristics of the corrosive fluid. (Author) 31 refs 1. Variational nodal transport methods for hexagonal and three-dimensional geometries International Nuclear Information System (INIS) The properties of the variational nodal method for neutron transport calculations are investigated. The method is generalized for three-dimensional multigroup criticality problems in both hexagonal-z and Cartesian geometries. The method is implemented as part of the Argonne National Laboratory Code DIF3D, and applied to a series of benchmark reactor calculations. Variational nodal methods are compared of nodal transport methods based on both interface-current and discrete ordinate approximations. Model problems are used to examine the effect of running each of the three classes of nodal transport methods on computers with massively parallel architectures 2. The impact of audit and feedback on nodal harvest in colorectal cancer Directory of Open Access Journals (Sweden) Bu Jingyu 2011-01-01 Full Text Available Abstract Background Adequate nodal harvest (≥ 12 lymph nodes in colorectal cancer has been shown to optimize staging and proposed as a quality indicator of colorectal cancer care. An audit within a single health district in Nova Scotia, Canada presented and published in 2002, revealed that adequate nodal harvest occurred in only 22% of patients. The goal of this current study was to identify factors associated with adequate nodal harvest, and specifically to examine the impact of the audit and feedback strategy on nodal harvest. Methods This population-based study included all patients undergoing resection for primary colorectal cancer in Nova Scotia, Canada, from 01 January 2001 to 31 December 2005. Linkage of the provincial cancer registry with other databases (hospital discharge, physician claims data, and national census data provided clinicodemographic, diagnostic, and treatment-event data. Factors associated with adequate nodal harvest were examined using multivariate logistic regression. The specific interaction between year and health district was examined to identify any potential effect of dissemination of the previously-performed audit. Results Among the 2,322 patients, the median nodal harvest was 8; overall, 719 (31% had an adequate nodal harvest. On multivariate analysis, audited health district (p Conclusions Improvements in colorectal cancer nodal harvest did occur over time. A published audit demonstrating suboptimal nodal harvest appeared to be an effective knowledge translation tool, though more so for the audited health district, suggesting a potentially beneficial effect of audit and feedback strategies. 3. Evaluation of the use of nodal methods for MTR neutronic analysis Energy Technology Data Exchange (ETDEWEB) Reitsma, F.; Mueller, E.Z. 1997-08-01 Although modern nodal methods are used extensively in the nuclear power industry, their use for research reactor analysis has been very limited. The suitability of nodal methods for material testing reactor analysis is investigated with the emphasis on the modelling of the core region (fuel assemblies). The nodal approachs performance is compared with that of the traditional finite-difference fine mesh approach. The advantages of using nodal methods coupled with integrated cross section generation systems are highlighted, especially with respect to data preparation, simplicity of use and the possibility of performing a great variety of reactor calculations subject to strict time limitations such as are required for the RERTR program. 4. Magnon nodal-line semimetals and drumhead surface states in anisotropic pyrochlore ferromagnets CERN Document Server Mook, Alexander; Mertig, Ingrid 2016-01-01 We introduce a new type of topological magnon matter: the magnonic pendant to electronic nodal-line semimetals. Magnon spectra of anisotropic pyrochlore ferromagnets feature twofold degeneracies of magnon bands along a closed loop in reciprocal space. These magnon nodal lines are topologically protected by the coexistence of inversion and time-reversal symmetry; they require the absence of spin-orbit interaction (no Dzyaloshinskii-Moriya interaction). We calculate the topological invariants of the nodal lines and show that details of the associated magnon drumhead surface states depend strongly on the termination of the surface. Magnon nodal-line semimetals complete the family of topological magnons in three-dimensional ferromagnetic materials. 5. Practically Coordinating OpenAIRE Durfee, Edmund H. 1999-01-01 To coordinate, intelligent agents might need to know something about themselves, about each other, about how others view themselves and others, about how others think others view themselves and others, and so on. Taken to an extreme, the amount of knowledge an agent might possess to coordinate its interactions with others might outstrip the agent's limited reasoning capacity (its available time, memory, and so on). Much of the work in studying and building multiagent systems has thus been dev... 6. Android Apps for Absolute Beginners CERN Document Server Jackson, Wallace 2011-01-01 Anybody can start building simple apps for the Android platform, and this book will show you how! Android Apps for Absolute Beginners takes you through the process of getting your first Android applications up and running using plain English and practical examples. It cuts through the fog of jargon and mystery that surrounds Android application development, and gives you simple, step-by-step instructions to get you started.* Teaches Android application development in language anyone can understand, giving you the best possible start in Android development * Provides simple, step-by-step exampl 7. Hereditary bone dysplasia with pathological fractures and nodal osteoarthropathy Energy Technology Data Exchange (ETDEWEB) Arendse, Regan [University of Stellenbosch, Department of Medicine, Tygerberg Hospital, Stellenbosch (South Africa); University of Cape Town, Division of Rheumatology, Groote Schuur Hospital, Cape Town (South Africa); Brink, Paul [University of Stellenbosch, Department of Medicine, Tygerberg Hospital, Stellenbosch (South Africa); Beighton, Peter [University of Cape Town, Division of Human Genetics, Faculty of Health Sciences, Cape Town (South Africa) 2009-12-15 A father and daughter both had multiple pathological fractures and nodal osteoarthropathy. The father, aged 50 years, had at least 20 healed fractures of the axial and appendicular skeleton, sustained by minor trauma over his 50-year lifespan, many of which had been surgically fixed prior to his first presentation to us. Fractures of the clavicles, thoracic cage and long bones of the arms and legs, had healed with malalignment and deformity. Healed fractures were complicated by ankylosis of the cervical vertebrae and both elbows. He also had osteoarthritis of the hands, with exuberant osteophytosis, and profound perceptive deafness. His general health was good, his intellect and facies were normal, and his sclerae were white. The daughter, aged 27 years, had sustained at least seven fractures of the axial and appendicular skeleton following trivial injuries, in distribution similar to those of the father. She had also experienced painful swelling of the fingers, which preceded progressive development of nodal osteoarthropathy. Her hearing was normal. In both individuals, biochemical and immunological investigations yielded normal results. It was not possible for molecular studies to be undertaken. Pedigree data were consistent with autosomal dominant transmission, and this disorder appeared to be a previously undocumented heritable skeletal dysplasia. (orig.) 8. Nodal Diffusion Burnable Poison Treatment for Prismatic Reactor Cores Energy Technology Data Exchange (ETDEWEB) A. M. Ougouag; R. M. Ferrer 2010-10-01 The prismatic block version of the High Temperature Reactor (HTR) considered as a candidate Very High Temperature Reactor (VHTR)design may use burnable poison pins in locations at some corners of the fuel blocks (i.e., assembly equivalent structures). The presence of any highly absorbing materials, such as these burnable poisons, within fuel blocks for hexagonal geometry, graphite-moderated High Temperature Reactors (HTRs) causes a local inter-block flux depression that most nodal diffusion-based method have failed to properly model or otherwise represent. The location of these burnable poisons near vertices results in an asymmetry in the morphology of the assemblies (or blocks). Hence the resulting inadequacy of traditional homogenization methods, as these “spread” the actually local effect of the burnable poisons throughout the assembly. Furthermore, the actual effect of the burnable poison is primarily local with influence in its immediate vicinity, which happens to include a small region within the same assembly as well as similar regions in the adjacent assemblies. Traditional homogenization methods miss this artifact entirely. This paper presents a novel method for treating the local effect of the burnable poison explicitly in the context of a modern nodal method. 9. Absolute Calibration of the Radio Astronomy Flux Density Scale at 22 to 43 GHz Using Planck OpenAIRE B. Partridge; López-Caniego, M.; Perley, R. A.; Stevens, J.; Butler, B. J.; Rocha, G.; Walter, B; Zacchei, A. 2015-01-01 The Planck mission detected thousands of extragalactic radio sources at frequencies from 28 to 857 GHz. Planck's calibration is absolute (in the sense that it is based on the satellite's annual motion around the Sun and the temperature of the cosmic microwave background), and its beams are well characterized at sub-percent levels. Thus Planck's flux density measurements of compact sources are absolute in the same sense. We have made coordinated VLA and ATCA observations of 65 strong, unresolv... 10. Value of the adenosine test for diagnosis of dual AV nodal physiology in patients with AV nodal reentrant tachycardia Institute of Scientific and Technical Information of China (English) 周斌全; 胡申江; 鲁端; 王建安 2002-01-01 Objectives: This study was aimed at assessing the value of the adenosine test for noninvasive diagnosis of dual AV nodal physiology(DAVNP) in patients with AV nodal reentrant tachycardia (AVNRT). Methods: 53 patients with paroxysmal supraventricular tachycardia (PSVT) were given incremental doses of adenosine intravenously during sinus rhythm before electrophysiological study. The adenosine test was repeated on a subset of 18 patients with AVNRT after radiofrequency catheter ablation. Results: Sudden increments of PR interval of more than 60 msec between two consecutive beats were observed in 26(83.9%) of 31 patients with typical AVNRT and 2 (9.1%) of 22 patients with AVRT and AT (P<0.01). The maximal PR increment between 2 consecutive beats in the AVNRT group(105±45ms) was significantly greater than that in the AVRT and AT group (20±13ms) (P<0.01).In postablation adenosine test, DAVNP was eliminated in all 8 patients who underwent slow pathway abolition that EPS showed the slow pathway disappeared and 4 of 10 patients who underwent slow pathway modification that EPS showed the slow pathway persisted. Six of 10 patients who exhibited persistent duality showed a marked reduction in the number of beats conducted in the slow pathway after adenosine injection(P<0.01).Conclusions: Administration of adenosine during sinus rhythm may be a useful bedside test for diagnosis of DAVNP in high percentage of patients with typical AVNRT and additionally for evaluating the effects of radiofrequency ablation. 11. Cosmology with Negative Absolute Temperatures CERN Document Server Vieira, J P P; Lewis, Antony 2016-01-01 Negative absolute temperatures (NAT) are an exotic thermodynamical consequence of quantum physics which has been known since the 1950's (having been achieved in the lab on a number of occasions). Recently, the work of Braun et al (2013) has rekindled interest in negative temperatures and hinted at a possibility of using NAT systems in the lab as dark energy analogues. This paper goes one step further, looking into the cosmological consequences of the existence of a NAT component in the Universe. NAT-dominated expanding Universes experience a borderline phantom expansion (w<-1$) with no Big Rip, and their contracting counterparts are forced to bounce after the energy density becomes sufficiently large. Both scenarios might be used to solve horizon and flatness problems analogously to standard inflation and bouncing cosmologies. We discuss the difficulties in obtaining and ending a NAT-dominated epoch, and possible ways of obtaining density perturbations with an acceptable spectrum. 12. Cosmology with negative absolute temperatures Science.gov (United States) Vieira, J. P. P.; Byrnes, Christian T.; Lewis, Antony 2016-08-01 Negative absolute temperatures (NAT) are an exotic thermodynamical consequence of quantum physics which has been known since the 1950's (having been achieved in the lab on a number of occasions). Recently, the work of Braun et al. [1] has rekindled interest in negative temperatures and hinted at a possibility of using NAT systems in the lab as dark energy analogues. This paper goes one step further, looking into the cosmological consequences of the existence of a NAT component in the Universe. NAT-dominated expanding Universes experience a borderline phantom expansion (w inflation and bouncing cosmologies. We discuss the difficulties in obtaining and ending a NAT-dominated epoch, and possible ways of obtaining density perturbations with an acceptable spectrum. 13. Comparison of programme MOBY-DICK with nodal programmes on benchmark problems International Nuclear Information System (INIS) In this paper we compare programme MOBY-DICK (which is diffusion difference programme) with nodal programmes no two-dimensional hexagonal benchmark problems for the VVER-type reactors (published by Chao and Shatilla). Nodal results are partly from one's own programme NODRAM and partly from literature. There is presented dependence on lattice pitch by difference programme and influence of boundary conditions (Author) 14. Coordinated unbundling DEFF Research Database (Denmark) Timmermans, Bram; Zabala-Iturriagagoitia, Jon Mikel 2013-01-01 not focused on the role this policy instrument can play in the promotion of (knowledge-intensive) entrepreneurship. This paper investigates this link in more detail and introduces the concept of coordinated unbundling as a strategy that can facilitate this purpose. We also present a framework on how... 15. Quasi-reflected interface conditions for variational nodal lattice calculations International Nuclear Information System (INIS) Quasi-reflected interface conditions are formulated to partially decouple periodic lattice effects from the pin-cell to pin-cell flux variation in the finite sub-element form of the variational nodal code VARIANT. With fuel-coolant homogenization eliminated, the interface variables that couple pin-cell sized nodes are divided into low-order and high-order spherical harmonic terms, and reflected interface conditions are applied to the high-order terms. This approach dramatically reduces the dimension of the resulting response matrices and leads to sharply reduced memory and CPU requirements for the solution of the resulting response matrix equations. The method is applied to a two-dimensional OECD/NEA PWR benchmark containing MOX and UO2 fuel assemblies. Results indicate that the quasi-reflected interface conditions result in very little loss of accuracy relative to the corresponding full spherical harmonics expansion. (authors) 16. A nonlinear analytic function expansion nodal method for transient calculations Energy Technology Data Exchange (ETDEWEB) Joo, Han Gyn; Park, Sang Yoon; Cho, Byung Oh; Zee, Sung Quun [Korea Atomic Energy Research Institute, Taejon (Korea, Republic of) 1998-12-31 The nonlinear analytic function expansion nodal (AFEN) method is applied to the solution of the time-dependent neutron diffusion equation. Since the AFEN method requires both the particular solution and the homogeneous solution to the transient fixed source problem, the derivation of the solution method is focused on finding the particular solution efficiently. To avoid complicated particular solutions, the source distribution is approximated by quadratic polynomials and the transient source is constructed such that the error due to the quadratic approximation is minimized, In addition, this paper presents a new two-node solution scheme that is derived by imposing the constraint of current continuity at the interface corner points. The method is verified through a series of application to the NEACRP PWR rod ejection benchmark problems. 6 refs., 2 figs., 1 tab. (Author) 17. Error Estimation and Accuracy Improvements in Nodal Transport Methods International Nuclear Information System (INIS) The accuracy of the solutions produced by the Discrete Ordinates neutron transport nodal methods is analyzed.The obtained new numerical methodologies increase the accuracy of the analyzed scheems and give a POSTERIORI error estimators. The accuracy improvement is obtained with new equations that make the numerical procedure free of truncation errors and proposing spatial reconstructions of the angular fluxes that are more accurate than those used until present. An a POSTERIORI error estimator is rigurously obtained for one dimensional systems that, in certain type of problems, allows to quantify the accuracy of the solutions. From comparisons with the one dimensional results, an a POSTERIORI error estimator is also obtained for multidimensional systems. LOCAL indicators, which quantify the spatial distribution of the errors, are obtained by the decomposition of the menctioned estimators. This makes the proposed methodology suitable to perform adaptive calculations. Some numerical examples are presented to validate the theoretical developements and to illustrate the ranges where the proposed approximations are valid 18. Contemporary Management of Recurrent Nodal Disease in Differentiated Thyroid Carcinoma. Science.gov (United States) Na'ara, Shorook; Amit, Moran; Fridman, Eran; Gil, Ziv 2016-01-01 Differentiated thyroid carcinoma (DTC) comprises over 90% of thyroid tumors and includes papillary and follicular carcinomas. Patients with DTC have an excellent prognosis, with a 10-year survival rate of over 90%. However, the risk of recurrent tumor ranges between 5% and 30% within 10 years of the initial diagnosis. Cervical lymph node disease accounts for the majority of recurrences and in most cases is detected during follow-up by ultrasound or elevated levels of serum thyroglobulin. Recurrent disease is accompanied by increased morbidity. The mainstay of treatment of nodal recurrence is surgical management. We provide an overview of the literature addressing surgical management of recurrent or persistent lymph node disease in patients with DTC. PMID:26886954 19. Contemporary Management of Recurrent Nodal Disease in Differentiated Thyroid Carcinoma Directory of Open Access Journals (Sweden) Shorook Na’ara 2016-01-01 Full Text Available Differentiated thyroid carcinoma (DTC comprises over 90% of thyroid tumors and includes papillary and follicular carcinomas. Patients with DTC have an excellent prognosis, with a 10-year survival rate of over 90%. However, the risk of recurrent tumor ranges between 5% and 30% within 10 years of the initial diagnosis. Cervical lymph node disease accounts for the majority of recurrences and in most cases is detected during follow-up by ultrasound or elevated levels of serum thyroglobulin. Recurrent disease is accompanied by increased morbidity. The mainstay of treatment of nodal recurrence is surgical management. We provide an overview of the literature addressing surgical management of recurrent or persistent lymph node disease in patients with DTC. 20. Contemporary Management of Recurrent Nodal Disease in Differentiated Thyroid Carcinoma. Science.gov (United States) Na'ara, Shorook; Amit, Moran; Fridman, Eran; Gil, Ziv 2016-01-28 Differentiated thyroid carcinoma (DTC) comprises over 90% of thyroid tumors and includes papillary and follicular carcinomas. Patients with DTC have an excellent prognosis, with a 10-year survival rate of over 90%. However, the risk of recurrent tumor ranges between 5% and 30% within 10 years of the initial diagnosis. Cervical lymph node disease accounts for the majority of recurrences and in most cases is detected during follow-up by ultrasound or elevated levels of serum thyroglobulin. Recurrent disease is accompanied by increased morbidity. The mainstay of treatment of nodal recurrence is surgical management. We provide an overview of the literature addressing surgical management of recurrent or persistent lymph node disease in patients with DTC. 1. Nodal wear model: corrosion in carbon blast furnace hearths Directory of Open Access Journals (Sweden) Verdeja, L. F. 2003-06-01 Full Text Available Criterions developed for the Nodal Wear Model (NWM were applied to estimate the shape of the corrosion profiles that a blast furnace hearth may acquire during its campaign. Taking into account design of the hearth, the boundary conditions, the characteristics of the refractory materials used and the operation conditions of the blast furnace, simulation of wear profiles with central well, mushroom and elephant foot shape were accomplished. The foundations of the NWM are constructed considering that the corrosion of the refractory is a function of the temperature present at each point (node of the liquid metal-refractory interface and the corresponding physical and chemical characteristics of the corrosive fluid. Se aplican los criterios del Modelo de Desgaste Nodal (MDN para la estimación de los perfiles de corrosión que podría ir adquiriendo el crisol de un homo alto durante su campaña. Atendiendo al propio diseño del crisol, a las condiciones límites de contorno, a las características del material refractario utilizado y a las condiciones de operación del horno, se consiguen simular perfiles de desgaste con "pozo central", con "forma de seta" ó de "pie de elefante". Los fundamentos del MDN se apoyan en la idea de considerar que la corrosión del refractario es función de la temperatura que el sistema pueda presentar en cada punto (nodo de la intercara refractario-fundido y de las correspondientes características físico-químicas del fluido corrosivo. 2. ProNodal acts via FGFR3 to govern duration of Shh expression in the prechordal mesoderm Science.gov (United States) Ellis, Pamela S.; Burbridge, Sarah; Soubes, Sandrine; Ohyama, Kyoji; Ben-Haim, Nadav; Chen, Canhe; Dale, Kim; Shen, Michael M.; Constam, Daniel; Placzek, Marysia 2015-01-01 The secreted glycoprotein sonic hedgehog (Shh) is expressed in the prechordal mesoderm, where it plays a crucial role in induction and patterning of the ventral forebrain. Currently little is known about how Shh is regulated in prechordal tissue. Here we show that in the embryonic chick, Shh is expressed transiently in prechordal mesoderm, and is governed by unprocessed Nodal. Exposure of prechordal mesoderm microcultures to Nodal-conditioned medium, the Nodal inhibitor CerS, or to an ALK4/5/7 inhibitor reveals that Nodal is required to maintain both Shh and Gsc expression, but whereas Gsc is largely maintained through canonical signalling, Nodal signals through a non-canonical route to maintain Shh. Further, Shh expression can be maintained by a recombinant Nodal cleavage mutant, proNodal, but not by purified mature Nodal. A number of lines of evidence suggest that proNodal acts via FGFR3. ProNodal and FGFR3 co-immunoprecipitate and proNodal increases FGFR3 tyrosine phosphorylation. In microcultures, soluble FGFR3 abolishes Shh without affecting Gsc expression. Further, prechordal mesoderm cells in which Fgfr3 expression is reduced by Fgfr3 siRNA fail to bind to proNodal. Finally, targeted electroporation of Fgfr3 siRNA to prechordal mesoderm in vivo results in premature Shh downregulation without affecting Gsc. We report an inverse correlation between proNodal-FGFR3 signalling and pSmad1/5/8, and show that proNodal-FGFR3 signalling antagonises BMP-mediated pSmad1/5/8 signalling, which is poised to downregulate Shh. Our studies suggest that proNodal/FGFR3 signalling governs Shh duration by repressing canonical BMP signalling, and that local BMPs rapidly silence Shh once endogenous Nodal-FGFR3 signalling is downregulated. PMID:26417042 3. Impact of radiation dose and standardized uptake value of (18)FDG PET on nodal control in locally advanced cervical cancer DEFF Research Database (Denmark) Ramlov, Anne; Kroon, Petra S; Jürgenliemk-Schulz, Ina M; 2015-01-01 by dose-maps from EBRT and IGABT. All PET/CT scans were re-evaluated and nodal maximal standard uptake value (SUVmax) was determined. Nodal failures were registered to planning scans and related to boosted nodes and treated volume. Relation between SUVmax and nodal control as well as the pattern... 4. TECHNICAL COORDINATION CERN Multimedia A. Ball Overview From a technical perspective, CMS has been in “beam operation” state since 6th November. The detector is fully closed with all components operational and the magnetic field is normally at the nominal 3.8T. The UXC cavern is normally closed with the radiation veto set. Access to UXC is now only possible during downtimes of LHC. Such accesses must be carefully planned, documented and carried out in agreement with CMS Technical Coordination, Experimental Area Management, LHC programme coordination and the CCC. Material flow in and out of UXC is now strictly controlled. Access to USC remains possible at any time, although, for safety reasons, it is necessary to register with the shift crew in the control room before going down.It is obligatory for all material leaving UXC to pass through the underground buffer zone for RP scanning, database entry and appropriate labeling for traceability. Technical coordination (notably Stephane Bally and Christoph Schaefer), the shift crew and run ... 5. Value of the adenosine test for diagnosis of dual AV nodal physiology in patients with AV nodal reentrant tachycardia Institute of Scientific and Technical Information of China (English) 周斌全; 胡申江; 等 2002-01-01 Objectives:This study was aimed at assessing the value of the adenosine test for noninvasive diagnosis of dual AV nodal physiology(DAVNP) in patients with AV nodal reentrant tachycardia(VANRT).Methods:53 patients with paroxysmal supraventricular tachycardia(PSVT) were given incremental doses of adenosine intravenously during sinus rhythm before electrophysiological study.The adenosine test was repeated on a subset of 18 patients with AVNRT after radiofrequency catheter ablation.Results:Sudden increments of PR interval of more than 60 msec between two consecutive beats were observed in 26(83.9%) of 31 patients with typical AVNRT and 2(9.1%) of 22 patients with AVRT and AT(P<0.01),The maximal PR increment between 2 consecutive beats in the AVNRT group(105±45ms) was significantly greater than that in the AVRT and AT group[(20±13ms) (P<0.01),In postablation adenosine test,DAVNP was eliminated in all 8 patients who underwent slow pathway abolition that EPS showed the slow pathway disappeared and 4 of 10 patients who underwent slow pathway modification that EPS showed the slow pathway disappeared and 4 of 10 patients who underwent slow pathway modification that EPS whosed the slow pathway persisted.Six of 10 patients whw exhibited persistent duality showed a marked reduction in the number of beats conducted in the slow pathway after adenosine injection(P<0.01),COnclusions:Administration of adenosine during sinus rhythm may be a useful bedside test for diagnosis of DAVNP in high percentage of patients with typical AVNRT and additionally for evaluating the effects of radiofrequency ablation. 6. Measurement of the absolute speed is possible? OpenAIRE Sergey V. Shevchenko; Tokarevsky, Vladimir V. 2016-01-01 One of popular problems, which are experimentally studied in physics in a long time, is the testing of the special relativity theory, first of all – measurements of isotropy and constancy of light speed; as well as attempts to determine so called “absolute speed”, i.e. the Earth speed in the absolute spacetime (absolute reference frame), if this spacetime (ARF) exists. Corresponding experiments aimed at the measuring of proper speed of some reference frame in oth... 7. Clinico-pathological signiifcance of extra-nodal spread in special types of breast cancer Institute of Scientific and Technical Information of China (English) Ecmel Isik Kaygusuz; Handan Cetiner; Hulya Yavuz 2014-01-01 Objective: To investigate the signiifcance of extra-nodal spread in special histological sub-types of breast cancer and the relationship of such spread with prognostic parameters. Methods: A total of 303 breast cancer cases were classiifed according to tumor type, and each tumor group was subdivided according to age, tumor diameter, lymph node metastasis, extra-nodal spread, vein invasion in the adjacent soft tissue, distant metastasis, and immunohistochemical characteristics [estrogen receptor (ER), progesterone receptor (PR) existence, p53, c-erbB-2, and proliferative rate (Ki-67)]. hTe 122 cases with extra-nodal spread were clinically followed up. Results: An extra-nodal spread was observed in 40% (122 cases) of the 303 breast cancer cases. hTe spread most frequently presented in micro papillary carcinoma histological sub-type (40 cases, 75%), but least frequently presents in mucinous carcinoma (2 cases, 8%). Patients with extra-nodal spread had a high average number of metastatic lymph nodes (8.3) and a high distant metastasis rate (38 cases, 31%) compared with patients without extra-nodal spread. Conclusion: hTe existence of extra-nodal spread in the examined breast cancer sub-types has predictive value in forecasting the number of metastatic lymph nodes and the disease prognosis. 8. Nodal price volatility reduction and reliability enhancement of restructured power systems considering demand-price elasticity International Nuclear Information System (INIS) With the development of restructured power systems, the conventional 'same for all customers' electricity price is getting replaced by nodal prices. Electricity prices will fluctuate with time and nodes. In restructured power systems, electricity demands will interact mutually with prices. Customers may shift some of their electricity consumption from time slots of high electricity prices to those of low electricity prices if there is a commensurate price incentive. The demand side load shift will influence nodal prices in return. This interaction between demand and price can be depicted using demand-price elasticity. This paper proposes an evaluation technique incorporating the impact of the demand-price elasticity on nodal prices, system reliability and nodal reliabilities of restructured power systems. In this technique, demand and price correlations are represented using the demand-price elasticity matrix which consists of self/cross-elasticity coefficients. Nodal prices are determined using optimal power flow (OPF). The OPF and customer damage functions (CDFs) are combined in the proposed reliability evaluation technique to assess the reliability enhancement of restructured power systems considering demand-price elasticity. The IEEE reliability test system (RTS) is simulated to illustrate the developed techniques. The simulation results show that demand-price elasticity reduces the nodal price volatility and improves both the system reliability and nodal reliabilities of restructured power systems. Demand-price elasticity can therefore be utilized as a possible efficient tool to reduce price volatility and to enhance the reliability of restructured power systems. (author) 9. Nodal signaling is required for closure of the anterior neural tube in zebrafish Directory of Open Access Journals (Sweden) Liu Qin 2007-11-01 Full Text Available Abstract Background Nodals are secreted signaling proteins with many roles in vertebrate development. Here, we identify a new role for Nodal signaling in regulating closure of the rostral neural tube of zebrafish. Results We find that the neural tube in the presumptive forebrain fails to close in zebrafish Nodal signaling mutants. For instance, the cells that will give rise to the pineal organ fail to move from the lateral edges of the neural plate to the midline of the diencephalon. The open neural tube in Nodal signaling mutants may be due in part to reduced function of N-cadherin, a cell adhesion molecule expressed in the neural tube and required for neural tube closure. N-cadherin expression and localization to the membrane are reduced in fish that lack Nodal signaling. Further, N-cadherin mutants and morphants have a pineal phenotype similar to that of mutants with deficiencies in the Nodal pathway. Overexpression of an activated form of the TGFβ Type I receptor Taram-A (Taram-A* cell autonomously rescues mesendoderm formation in fish with a severe decrease in Nodal signaling. We find that overexpression of Taram-A* also corrects their open neural tube defect. This suggests that, as in mammals, the mesoderm and endoderm have an important role in regulating closure of the anterior neural tube of zebrafish. Conclusion This work helps establish a role for Nodal signals in neurulation, and suggests that defects in Nodal signaling could underlie human neural tube defects such as exencephaly, a fatal condition characterized by an open neural tube in the anterior brain. 10. Regional nodal relapse in surgically staged Merkel cell carcinoma Energy Technology Data Exchange (ETDEWEB) Hoeller, Ulrike; Mueller, Thomas; Schubert, Tina; Budach, Volker; Ghadjar, Pirus [Charite Universitaetsmedizin Berlin, Department of Radiation Oncology, Berlin (Germany); Brenner, Winfried [Charite Universitaetsmedizin Berlin, Department of Nuclear Medicine, Berlin (Germany); Kiecker, Felix [Charite Universitaetsmedizin Berlin, Department of Dermatology, Berlin (Germany); Schicke, Bernd [Tumor Center Berlin, Berlin (Germany); Haase, Oliver [Charite Universitaetsmedizin Berlin, Department of Surgery, Berlin (Germany) 2014-10-08 The nodal relapse pattern of surgically staged Merkel cell carcinoma (MCC) with/without elective nodal radiotherapy (RT) was studied in a single institution. A total of 51 patients with MCC, 33 % UICC stage I, 14 % II, 53 % III (4 lymph node metastases of unknown primary) were eligible. All patients had surgical staging: 23 patients sentinel node biopsy (SNB), 22 patients SNB followed by lymphadenectomy (LAD) and 6 patients LAD. In all, 94 % of the primary tumors (PT) were completely resected; 57 % of patients received RT, 51 % of known PT sites, 33 % (8/24 patients) regional RT to snN0 nodes and 68 % (17/27 patients) to pN+ nodes, mean reference dose 51.5 and 50 Gy, respectively. Mean follow-up was 6 years (range 2-14 years). A total of 22 % (11/51) patients developed regional relapses (RR); the 5-year RR rate was 27 %. In snN0 sites (stage I/II), relapse occurred in 5 of 14 nonirradiated vs. none of 8 irradiated sites (p = 0.054), resulting in a 5-year RR rate of 33 % versus 0 % (p = 0.16). The crude RR rate was lower in stage I (12 %, 2/17 patients) than for stage II (43 %, 3/7 patients). In stage III (pN+), RR appeared to be less frequent in irradiated sites (18 %, 3/14 patients) compared with nonirradiated sites (33 %, 3/10 patients, p = 0.45) with 5-year RR rates of 23 % vs. 34 %, respectively. Our data suggest that adjuvant nodal RT plays a major role even if the sentinel nodes were negative. Adjuvant RT of the lymph nodes in patients with stage IIa tumors and RT after LAD in stage III tumors is proposed and should be evaluated prospectively. (orig.) [German] Untersucht wurde das regionaere Rezidivmuster des Merkelzell-Karzinoms (MCC) nach chirurgischem Staging und stadienadaptierter Therapie. Eingeschlossen wurden 51 Patienten mit lokalisiertem MCC: 33 % hatten UICC-Stadium-I-, 14 % -II-, 53 % -III-Tumoren (davon 4 Lymphknotenmetastasen eines unbekannten Primaertumors). Alle Patienten erhielten ein chirurgisches Staging: 23 Waechterlymphknotenbiopsien (SNB 11. Absolute surface reconstruction by slope metrology and photogrammetry Science.gov (United States) Dong, Yue Developing the manufacture of aspheric and freeform optical elements requires an advanced metrology method which is capable of inspecting these elements with arbitrary freeform surfaces. In this dissertation, a new surface measurement scheme is investigated for such a purpose, which is to measure the absolute surface shape of an object under test through its surface slope information obtained by photogrammetric measurement. A laser beam propagating toward the object reflects on its surface while the vectors of the incident and reflected beams are evaluated from the four spots they leave on the two parallel transparent windows in front of the object. The spots' spatial coordinates are determined by photogrammetry. With the knowledge of the incident and reflected beam vectors, the local slope information of the object surface is obtained through vector calculus and finally yields the absolute object surface profile by a reconstruction algorithm. An experimental setup is designed and the proposed measuring principle is experimentally demonstrated by measuring the absolute surface shape of a spherical mirror. The measurement uncertainty is analyzed, and efforts for improvement are made accordingly. In particular, structured windows are designed and fabricated to generate uniform scattering spots left by the transmitted laser beams. Calibration of the fringe reflection instrument, another typical surface slope measurement method, is also reported in the dissertation. Finally, a method for uncertainty analysis of a photogrammetry measurement system by optical simulation is investigated. 12. Inequalities, Absolute Value, and Logical Connectives. Science.gov (United States) Parish, Charles R. 1992-01-01 Presents an approach to the concept of absolute value that alleviates students' problems with the traditional definition and the use of logical connectives in solving related problems. Uses a model that maps numbers from a horizontal number line to a vertical ray originating from the origin. Provides examples solving absolute value equations and… 13. Absolute Income, Relative Income, and Happiness Science.gov (United States) Ball, Richard; Chernova, Kateryna 2008-01-01 This paper uses data from the World Values Survey to investigate how an individual's self-reported happiness is related to (i) the level of her income in absolute terms, and (ii) the level of her income relative to other people in her country. The main findings are that (i) both absolute and relative income are positively and significantly… 14. Investigating Absolute Value: A Real World Application Science.gov (United States) Kidd, Margaret; Pagni, David 2009-01-01 Making connections between various representations is important in mathematics. In this article, the authors discuss the numeric, algebraic, and graphical representations of sums of absolute values of linear functions. The initial explanations are accessible to all students who have experience graphing and who understand that absolute value simply… 15. Monolithically integrated absolute frequency comb laser system Energy Technology Data Exchange (ETDEWEB) Wanke, Michael C. 2016-07-12 Rather than down-convert optical frequencies, a QCL laser system directly generates a THz frequency comb in a compact monolithically integrated chip that can be locked to an absolute frequency without the need of a frequency-comb synthesizer. The monolithic, absolute frequency comb can provide a THz frequency reference and tool for high-resolution broad band spectroscopy. 16. TECHNICAL COORDINATION CERN Multimedia A. Ball 2010-01-01 Operational Experience At the end of the first full-year running period of LHC, CMS is established as a reliable, robust and mature experiment. In particular common systems and infrastructure faults accounted for <0.6 % CMS downtime during LHC pp physics. Technical operation throughout the entire year was rather smooth, the main faults requiring UXC access being sub-detector power systems and rack-cooling turbines. All such problems were corrected during scheduled technical stops, in the shadow of tunnel access needed by the LHC, or in negotiated accesses or access extensions. Nevertheless, the number of necessary accesses to the UXC averaged more than one per week and the technical stops were inevitably packed with work packages, typically 30 being executed within a few days, placing a high load on the coordination and area management teams. It is an appropriate moment for CMS Technical Coordination to thank all those in many CERN departments and in the Collaboration, who were involved in CMS techni... 17. Hybrid nodal methods in the solution of the diffusion equations in X Y geometry; Metodos nodales hibridos en la solucion de las ecuaciones de difusion en geometria XY Energy Technology Data Exchange (ETDEWEB) Hernandez M, N. [CFE, Carretera Cardel-Nautla Km. 43.5, 91680 Veracruz (Mexico); Alonso V, G.; Valle G, E. del [IPN-ESFM, 07738 Mexico D.F. (Mexico)]. e-mail: nhmiranda@mexico.com 2003-07-01 In 1979, Hennart and collaborators applied several schemes of classic finite element in the numerical solution of the diffusion equations in X Y geometry and stationary state. Almost two decades then, in 1996, himself and other collaborators carried out a similar work but using nodal schemes type finite element. Continuing in this last direction, in this work a group it is described a set of several Hybrid Nodal schemes denominated (NH) as well as their application to solve the diffusion equations in multigroup in stationary state and X Y geometry. The term hybrid nodal it means that such schemes interpolate not only Legendre moments of face and of cell but also the values of the scalar flow of neutrons in the four corners of each cell or element of the spatial discretization of the domain of interest. All the schemes here considered are polynomials like they were it their predecessors. Particularly, its have developed and applied eight different hybrid nodal schemes that its are very nearby related with those developed by Hennart and collaborators in the past. It is treated of schemes in those that nevertheless that decreases the number of interpolation parameters it is conserved the accurate in relation to the bi-quadratic and bi-cubic schemes. Of these eight, three were described and applied in a previous work. It is the bi-lineal classic scheme as well as the hybrid nodal schemes, bi-quadratic and bi-cubic for that here only are described the other 5 hybrid nodal schemes although they are provided numerical results for several test problems with all them. (Author) 18. Multi-group nodal expansion method for reactor core analysis Energy Technology Data Exchange (ETDEWEB) Cho, Byung Oh; Joo, Han Gyu; Park, Sang Yoon; Zee, Sung Quun; Kim, Ha Yong [Korea Atomic Energy Research Institute, Taejeon (Korea) 2000-02-01 MASTER-2.0 is a nuclear design code based on the two group diffusion theory to calculate the steady-state and transient pressurized water reactor core in a 3-dimensional Cartesian or hexagonal geometry. The response matrix based NEM has been extended for multi-group neutron diffusion theory in order to increase the computational accuracy for rectangular geometry. Coarse mesh rebalancing scheme is used to accelerate the convergence of iteration process. The transverse leakage profile involved in NEM is approximated by a parabola. Its coefficients are determined by using the continuity condition at interfaces or the intra-nodal flux shape including node vertices. For the verification of the multi-group NEM routine of MASTER-2.0, the combinations of the transverse leakage approximation with NEM were tested using two benchmark problems in order to check the sound operation of the routine. Comparisons made reveal that the accuracy of the NEM for the prediction of eigenvalue and power distribution is quite good and the four-group cross sections generated by CASMO-3 work properly in the MASTER code system. 11 refs., 7 figs., 4 tabs. (Author) 19. MicroRNA expression in nodal and extranodal Diffuse Large B-cell Lymphoma DEFF Research Database (Denmark) Mandrup, Charlotte; Petersen, Anders; Højfeldt, Anne Dirks; MicroRNA expression in nodal and extranodal Diffuse Large B-cell Lymphoma C. Mandrup1, A. Petersen1, A. D. Hoejfeldt1, H. F. Thomsen1, J. Madsen1, J. Dahlgaard1, P. Johansen2, A. Bukh1, K. Dybkaer1 and H. E Johnsen1. 1Department of Hematology, 2Pathological Institute, Aalborg Hospital, Aarhus...... University Hospital, Aalborg, Denmark Introduction: The aim of this project was to analyse microRNA (miRNA) expression in nodal and extranodal diffuse large B-cell lymphoma (DLBCL). Manifestation at diagnosis may be nodal and/or extranodal. At present, there are no known determinants for none...... of the manifestations, and no way to predict the potential progression from nodal to extranodal disease. miRNA are small regulatory RNA molecules with core function to repress/cleave sequence complementary mRNA targets. Abnormalities in miRNA genetics and expression are known to affect initiation and development... 20. Many-body nodal hypersurface and domain averages for correlated wave functions CERN Document Server Hu, Shuming; Mitas, Lubos 2013-01-01 We outline the basic notions of nodal hypersurface and domain averages for antisymmetric wave functions. We illustrate their properties and analyze the results for a few electron explicitly solvable cases and discuss possible further developments. 1. The Emergence of Topological Nodal Points in Photonic Crystal with Mirror Symmetry CERN Document Server He, Wen-Yu 2014-01-01 We show that topological nodal points can emerge in photonic crystal possessing mirror symmetry. The mechanism of generating topological nodal points is discussed in a two-dimensional photonic square lattice, in which four topological nodal points split out naturally after the touching of two bands with different parity. The emergence of such nodal points, characterized by vortex structure in momentum space, is attributed to the unavoidable band crossing protected by mirror symmetry. The topological nodes can be unbuckled through breaking the mirror symmetry and a photonic Chern insulator can be achieved through time reversal symmetry breaking. The joint effect of breaking time reversal symmetry and breaking inversion symmetry is further found to strengthen the finite size effect, providing ways to engineer helical edge states. 2. Coordination Capacity CERN Document Server Cuff, Paul; Cover, Thomas 2009-01-01 We develop elements of a theory of cooperation and coordination in networks. Rather than considering a communication network as a means of distributing information, or of reconstructing random processes at remote nodes, we ask what dependence can be established among the nodes given the communication constraints. Specifically, in a network with communication rates between the nodes, we ask what is the set of all achievable joint distributions p(x1, ..., xm) of actions at the nodes on the network. Several networks are solved, including arbitrarily large cascade networks. Distributed cooperation can be the solution to many problems such as distributed games, distributed control, and establishing mutual information bounds on the influence of one part of a physical system on another. 3. Anisotropic density fluctuations, plasmons, and Friedel oscillations in nodal line semimetal OpenAIRE Rhim, Jun-Won; Kim, Yong Baek 2015-01-01 Motivated by recent experimental efforts on three-dimensional semimetals, we investigate the static and dynamic density response of the nodal line semimetal by computing the polarizability for both undoped and doped cases. The nodal line semimetal in the absence of doping is characterized by a ring-shape zero energy contour in momentum space, which may be considered as a collection of Dirac points. In the doped case, the Fermi surface has a torus shape and two independent processes of the mom... 4. Prognosis and segment-specific nodal spread of primary lung cancer in the right lower lobe OpenAIRE Tomizawa, Kenji; Suda, Kenichi; Takemoto, Toshiki; Mizuno, Tetsuya; Kuroda, Hiroaki; Sakakura, Noriaki; Iwasaki, Takuya; Sakaguchi, Masahiro; Kuwano, Hiroyuki; Mitsudomi, Tetsuya; Sakao, Yukinori 2015-01-01 Background Although lobe-specific nodal spread of primary lung cancer has been recently described, segment-specific nodal spread remains unclear. We investigated the frequency of hailer and mediastinal lymph node involvement and survival in patients with tumors located in the superior segment (SS) and basal segment (BS) in the right lower lobe. Methods Two hundred and sixty-three patients with primary lung cancer originating in the right lower lobe underwent lobectomy with systematic mediasti... 5. TGF-β promotes glioma cell growth via activating Nodal expression through Smad and ERK1/2 pathways Energy Technology Data Exchange (ETDEWEB) Sun, Jing [Department of Neurology, The Second Affiliated Hospital of Wenzhou Medical University, Wenzhou 325000, Zhejiang (China); Liu, Su-zhi [Department of Neurology, The Affiliated Taizhou Hospital, Wenzhou Medical University, Taizhou 317000, Zhejiang (China); Lin, Yan; Cao, Xiao-pan [Department of Neurology, The Second Affiliated Hospital of Wenzhou Medical University, Wenzhou 325000, Zhejiang (China); Liu, Jia-ming, E-mail: wzljm@126.com [School of Environmental Science and Public Health, Wenzhou Medical University, Wenzhou 325035, Zhejiang (China) 2014-01-17 Highlights: •TGF-β promoted Nodal expression in glioma cells. •TGF-β promoted Nodal expression via activating Smad and ERK1/2 pathways. •TGF-β promotes glioma cell growth via activating Nodal expression. -- Abstract: While there were certain studies focusing on the mechanism of TGF-β promoting the growth of glioma cells, the present work revealed another novel mechanism that TGF-β may promote glioma cell growth via enhancing Nodal expression. Our results showed that Nodal expression was significantly upregulated in glioma cells when TGF-β was added, whereas the TGF-β-induced Nodal expression was evidently inhibited by transfection Smad2 or Smad3 siRNAs, and the suppression was especially significant when the Smad3 was downregulated. Another, the attenuation of TGF-β-induced Nodal expression was observed with blockade of the ERK1/2 pathway also. Further detection of the proliferation, apoptosis, and invasion of glioma cells indicated that Nodal overexpression promoted the proliferation and invasion of tumor cells and inhibited their apoptosis, resembling the effect of TGF-β addition. Downregulation of Nodal expression via transfection Nodal-specific siRNA in the presence of TGF-β weakened the promoting effect of the latter on glioma cells growth, and transfecting Nodal siRNA alone in the absence of exogenous TGF-β more profoundly inhibited the growth of glioma cells. These results demonstrated that while both TGF-β and Nodal promoted glioma cells growth, the former might exert such effect by enhancing Nodal expression, which may form a new target for glioma therapy. 6. Mathematical embryology: the fluid mechanics of nodal cilia Science.gov (United States) Smith, D. J.; Smith, A. A.; Blake, J. R. 2011-07-01 Left-right symmetry breaking is critical to vertebrate embryonic development; in many species this process begins with cilia-driven flow in a structure termed the node'. Primary whirling' cilia, tilted towards the posterior, transport morphogen-containing vesicles towards the left, initiating left-right asymmetric development. We review recent theoretical models based on the point-force stokeslet and point-torque rotlet singularities, explaining how rotation and surface-tilt produce directional flow. Analysis of image singularity systems enforcing the no-slip condition shows how tilted rotation produces a far-field stresslet' directional flow, and how time-dependent point-force and time-independent point-torque models are in this respect equivalent. Associated slender body theory analysis is reviewed; this approach enables efficient and accurate simulation of three-dimensional time-dependent flow, time-dependence being essential in predicting features of the flow such as chaotic advection, which have subsequently been determined experimentally. A new model for the nodal flow utilising the regularized stokeslet method is developed, to model the effect of the overlying Reichert's membrane. Velocity fields and particle paths within the enclosed domain are computed and compared with the flow profiles predicted by previous membrane-less' models. Computations confirm that the presence of the membrane produces flow-reversal in the upper region, but no continuous region of reverse flow close to the epithelium. The stresslet far-field is no longer evident in the membrane model, due to the depth of the cavity being of similar magnitude to the cilium length. Simulations predict that vesicles released within one cilium length of the epithelium are generally transported to the left via a loopy drift' motion, sometimes involving highly unpredictable detours around leftward cilia [truncated 7. Coexistent Types of Atrioventricular Nodal Re-Entrant Tachycardia Science.gov (United States) Marine, Joseph E.; Latchamsetty, Rakesh; Zografos, Theodoros; Tanawuttiwat, Tanyanan; Sheldon, Seth H.; Buxton, Alfred E.; Calkins, Hugh; Morady, Fred; Josephson, Mark E. 2015-01-01 Background— There is evidence that atypical fast–slow and typical atrioventricular nodal re-entrant tachycardia (AVNRT) do not use the same limb for fast conduction, but no data exist on patients who have presented with both typical and atypical forms of this tachycardia. We compared conduction intervals during typical and atypical AVNRT that occurred in the same patient. Methods and Results— In 20 of 1299 patients with AVNRT, both typical and atypical AVNRT were induced at electrophysiology study by pacing maneuvers and autonomic stimulation or occurred spontaneously. The mean age of the patients was 47.6±10.9 years (range, 32–75 years), and 11 patients (55%) were women. Tachycardia cycle lengths were 368.0±43.1 and 365.8±41.1 ms, and earliest retrograde activation was recorded at the coronary sinus ostium in 60% and 65% of patients with typical and atypical AVNRT, respectively. Thirteen patients (65%) displayed atypical AVNRT with fast–slow characteristics. By comparing conduction intervals during slow–fast and fast–slow AVNRT in the same patient, fast pathway conduction times during the 2 types of AVNRT were calculated. The mean difference between retrograde fast pathway conduction during slow–fast AVNRT and anterograde fast pathway conduction during fast–slow AVNRT was 41.8±39.7 ms and was significantly different when compared with the estimated between-measurement error (P=0.0055). Conclusions— Our data provide further evidence that typical slow–fast and atypical fast–slow AVNRT use different anatomic pathways for fast conduction. PMID:26155802 8. RUN COORDINATION CERN Document Server C. Delaere 2013-01-01 Since the LHC ceased operations in February, a lot has been going on at Point 5, and Run Coordination continues to monitor closely the advance of maintenance and upgrade activities. In the last months, the Pixel detector was extracted and is now stored in the pixel lab in SX5; the beam pipe has been removed and ME1/1 removal has started. We regained access to the vactank and some work on the RBX of HB has started. Since mid-June, electricity and cooling are back in S1 and S2, allowing us to turn equipment back on, at least during the day. 24/7 shifts are not foreseen in the next weeks, and safety tours are mandatory to keep equipment on overnight, but re-commissioning activities are slowly being resumed. Given the (slight) delays accumulated in LS1, it was decided to merge the two global runs initially foreseen into a single exercise during the week of 4 November 2013. The aim of the global run is to check that we can run (parts of) CMS after several months switched off, with the new VME PCs installed, th... 9. RUN COORDINATION CERN Multimedia Christophe Delaere 2013-01-01 The focus of Run Coordination during LS1 is to monitor closely the advance of maintenance and upgrade activities, to smooth interactions between subsystems and to ensure that all are ready in time to resume operations in 2015 with a fully calibrated and understood detector. After electricity and cooling were restored to all equipment, at about the time of the last CMS week, recommissioning activities were resumed for all subsystems. On 7 October, DCS shifts began 24/7 to allow subsystems to remain on to facilitate operations. That culminated with the Global Run in November (GriN), which took place as scheduled during the week of 4 November. The GriN has been the first centrally managed operation since the beginning of LS1, and involved all subdetectors but the Pixel Tracker presently in a lab upstairs. All nights were therefore dedicated to long stable runs with as many subdetectors as possible. Among the many achievements in that week, three items may be highlighted. First, the Strip... 10. The Simplicity Argument and Absolute Morality Science.gov (United States) Mijuskovic, Ben 1975-01-01 In this paper the author has maintained that there is a similarity of thought to be found in the writings of Cudworth, Emerson, and Husserl in his investigation of an absolute system of morality. (Author/RK) 11. Absolute calibration technique for spontaneous fission sources International Nuclear Information System (INIS) An absolute calibration technique for a spontaneously fissioning nuclide (which involves no arbitrary parameters) allows unique determination of the detector efficiency for that nuclide, hence of the fission source strength 12. Absolute distance metrology for space interferometers OpenAIRE Swinkels, B L; Wendrich, T.J.; Bhattacharya, N; Wielders, A.A.; Braat, J.J.M. 2004-01-01 Space interferometers consisting of several free flying telescopes, such as the planned Darwin mission, require a complex metrology system to make all the components operate as a single instrument. Our research focuses on one of its sub-systems that measures the absolute distance between two satellites with high accuracy. For Darwin the required accuracy would be in the order of 10 μm over 250 meter. To measure this absolute distance, we are currently exploring the frequency sweeping interfer... 13. Ultrasound-guided core biopsy: an effective method of detecting axillary nodal metastases. LENUS (Irish Health Repository) Solon, Jacqueline G 2012-02-01 BACKGROUND: Axillary nodal status is an important prognostic predictor in patients with breast cancer. This study evaluated the sensitivity and specificity of ultrasound-guided core biopsy (Ax US-CB) at detecting axillary nodal metastases in patients with primary breast cancer, thereby determining how often sentinel lymph node biopsy could be avoided in node positive patients. STUDY DESIGN: Records of patients presenting to a breast unit between January 2007 and June 2010 were reviewed retrospectively. Patients who underwent axillary ultrasonography with or without preoperative core biopsy were identified. Sensitivity, specificity, positive predictive value, and negative predictive value for ultrasonography and percutaneous biopsy were evaluated. RESULTS: Records of 718 patients were reviewed, with 445 fulfilling inclusion criteria. Forty-seven percent (n = 210\\/445) had nodal metastases, with 110 detected by Ax US-CB (sensitivity 52.4%, specificity 100%, positive predictive value 100%, negative predictive value 70.1%). Axillary ultrasonography without biopsy had sensitivity and specificity of 54.3% and 97%, respectively. Lymphovascular invasion was an independent predictor of nodal metastases (sensitivity 60.8%, specificity 80%). Ultrasound-guided core biopsy detected more than half of all nodal metastases, sparing more than one-quarter of all breast cancer patients an unnecessary sentinel lymph node biopsy. CONCLUSIONS: Axillary ultrasonography, when combined with core biopsy, is a valuable component of the management of patients with primary breast cancer. Its ability to definitively identify nodal metastases before surgical intervention can greatly facilitate a patient\\'s preoperative integrated treatment plan. In this regard, we believe our study adds considerably to the increasing data, which indicate the benefit of Ax US-CB in the preoperative detection of nodal metastases. 14. Source Expansion Nodal Solution of SP3 Equations with P1 Coarse Mesh Finite Difference Formulation International Nuclear Information System (INIS) In order to effectively account for the transport effects in core calculations, the SP3 equations are adopted in some of the existing nodal diffusion codes such as PARCS and DYN3D. The advantage of using the SP3 equations comes from the similarity between the SP3 equations and the diffusion or P1 equation that make it possible to use the existing code's architecture and solution methods that were developed for the nodal diffusion equation. The only difference is that there are one more balance equation and one additional unknown, the second angular moment. For the solution of the SP3 equations by the nodal method, the nodal expansion method was first developed and the source expansion nodal method(SENM) was introduced as an accurate kernel to capture correctly the drastic variation of the second angular moment near material interfaces. The exponential part of the source expansion nodal solution turned out to be very effective in describing the strong gradient in the second angular flux near the surface and this capability of SENM provides better accuracy than the corresponding NEM solution. On the other hand, a nodal solution kernel can be formulated locally employing either a one-node or two- node formulation. The one-node formulation requires incoming current conditions while the two-node formulation requires node average fluxes. In principle, these boundary conditions can be provided by the global coarse mesh finite difference (CMFD) solution that includes both zero-th and second angular moment fluxes. Inclusion of the second angular moments in the CMFD system, however, can lead to potential instability because of the large gradient of the second angular moments near each interface. This work is to develop a way not to use the second angular moment in the CMFD equation by keeping the ordinary P1 CMFD formulation 15. Patterns of failure after the reduced volume approach for elective nodal irradiation in nasopharyngeal carcinoma Energy Technology Data Exchange (ETDEWEB) Seol, Ki Ho; Lee, Jeong Eun [Dept. of Radiation Oncology, Kyungpook National University School of Medicine, Daegu (Korea, Republic of) 2016-03-15 To evaluate the patterns of nodal failure after radiotherapy (RT) with the reduced volume approach for elective neck nodal irradiation (ENI) in nasopharyngeal carcinoma (NPC). Fifty-six NPC patients who underwent definitive chemoradiotherapy with the reduced volume approach for ENI were reviewed. The ENI included retropharyngeal and level II lymph nodes, and only encompassed the echelon inferior to the involved level to eliminate the entire neck irradiation. Patients received either moderate hypofractionated intensity-modulated RT for a total of 72.6 Gy (49.5 Gy to elective nodal areas) or a conventional fractionated three-dimensional conformal RT for a total of 68.4-72 Gy (39.6-45 Gy to elective nodal areas). Patterns of failure, locoregional control, and survival were analyzed. The median follow-up was 38 months (range, 3 to 80 months). The out-of-field nodal failure when omitting ENI was none. Three patients developed neck recurrences (one in-field recurrence in the 72.6 Gy irradiated nodal area and two in the elective irradiated region of 39.6 Gy). Overall disease failure at any site developed in 11 patients (19.6%). Among these, there were six local failures (10.7%), three regional failures (5.4%), and five distant metastases (8.9%). The 3-year locoregional control rate was 87.1%, and the distant failure-free rate was 90.4%; disease-free survival and overall survival at 3 years was 80% and 86.8%, respectively. No patient developed nodal failure in the omitted ENI site. Our investigation has demonstrated that the reduced volume approach for ENI appears to be a safe treatment approach in NPC. 16. Churchill regulates cell movement and mesoderm specification by repressing Nodal signaling Directory of Open Access Journals (Sweden) Mentzer Laura 2007-11-01 Full Text Available Abstract Background Cell movements are essential to the determination of cell fates during development. The zinc-finger transcription factor, Churchill (ChCh has been proposed to regulate cell fate by regulating cell movements during gastrulation in the chick. However, the mechanism of action of ChCh is not understood. Results We demonstrate that ChCh acts to repress the response to Nodal-related signals in zebrafish. When ChCh function is abrogated the expression of mesodermal markers is enhanced while ectodermal markers are expressed at decreased levels. In cell transplant assays, we observed that ChCh-deficient cells are more motile than wild-type cells. When placed in wild-type hosts, ChCh-deficient cells often leave the epiblast, migrate to the germ ring and are later found in mesodermal structures. We demonstrate that both movement of ChCh-compromised cells to the germ ring and acquisition of mesodermal character depend on the ability of the donor cells to respond to Nodal signals. Blocking Nodal signaling in the donor cells at the levels of Oep, Alk receptors or Fast1 inhibited migration to the germ ring and mesodermal fate change in the donor cells. We also detect additional unusual movements of transplanted ChCh-deficient cells which suggests that movement and acquisition of mesodermal character can be uncoupled. Finally, we demonstrate that ChCh is required to limit the transcriptional response to Nodal. Conclusion These data establish a broad role for ChCh in regulating both cell movement and Nodal signaling during early zebrafish development. We show that chch is required to limit mesodermal gene expression, inhibit Nodal-dependant movement of presumptive ectodermal cells and repress the transcriptional response to Nodal signaling. These findings reveal a dynamic role for chch in regulating cell movement and fate during early development. 17. Cis-regulatory control of the nodal gene, initiator of the sea urchin oral ectoderm gene network OpenAIRE Nam, Jongmin; Su, Yi-Hsien; Lee, Pei Yun; Robertson, Anthony J; Coffman, James A.; Davidson, Eric H. 2007-01-01 Expression of the nodal gene initiates the gene regulatory network which establishes the transcriptional specification of the oral ectoderm in the sea urchin embryo. This gene encodes a TGFβ ligand, and in Strongylocentrotus purpuratus its transcription is activated in the presumptive oral ectoderm at about the 30-cell stage. Thereafter Nodal signaling occurs among all cells of the oral ectoderm territory, and nodal expression is required for expression of oral ectoderm regulatory genes. The ... 18. Nodal signaling is required for mesodermal and ventral but not for dorsal fates in the indirect developing hemichordate, Ptychodera flava OpenAIRE Eric Röttinger; DuBuc, Timothy Q.; Aldine R. Amiel; Martindale, Mark Q. 2015-01-01 ABSTRACT Nodal signaling plays crucial roles in vertebrate developmental processes such as endoderm and mesoderm formation, and axial patterning events along the anteroposterior, dorsoventral and left-right axes. In echinoderms, Nodal plays an essential role in the establishment of the dorsoventral axis and left-right asymmetry, but not in endoderm or mesoderm induction. In protostomes, Nodal signaling appears to be involved only in establishing left-right asymmetry. Hence, it is hypothesized... 19. A global algorithm for estimating Absolute Salinity Directory of Open Access Journals (Sweden) T. J. McDougall 2012-12-01 Full Text Available The International Thermodynamic Equation of Seawater – 2010 has defined the thermodynamic properties of seawater in terms of a new salinity variable, Absolute Salinity, which takes into account the spatial variation of the composition of seawater. Absolute Salinity more accurately reflects the effects of the dissolved material in seawater on the thermodynamic properties (particularly density than does Practical Salinity. When a seawater sample has standard composition (i.e. the ratios of the constituents of sea salt are the same as those of surface water of the North Atlantic, Practical Salinity can be used to accurately evaluate the thermodynamic properties of seawater. When seawater is not of standard composition, Practical Salinity alone is not sufficient and the Absolute Salinity Anomaly needs to be estimated; this anomaly is as large as 0.025 g kg−1 in the northernmost North Pacific. Here we provide an algorithm for estimating Absolute Salinity Anomaly for any location (x, y, p in the world ocean. To develop this algorithm, we used the Absolute Salinity Anomaly that is found by comparing the density calculated from Practical Salinity to the density measured in the laboratory. These estimates of Absolute Salinity Anomaly however are limited to the number of available observations (namely 811. In order to provide a practical method that can be used at any location in the world ocean, we take advantage of approximate relationships between Absolute Salinity Anomaly and silicate concentrations (which are available globally. 20. Topological nodal-line fermions in spin-orbit metal PbTaSe2 Science.gov (United States) Bian, Guang; Chang, Tay-Rong; Sankar, Raman; Xu, Su-Yang; Zheng, Hao; Neupert, Titus; Chiu, Ching-Kai; Huang, Shin-Ming; Chang, Guoqing; Belopolski, Ilya; Sanchez, Daniel S.; Neupane, Madhab; Alidoust, Nasser; Liu, Chang; Wang, Baokai; Lee, Chi-Cheng; Jeng, Horng-Tay; Zhang, Chenglong; Yuan, Zhujun; Jia, Shuang; Bansil, Arun; Chou, Fangcheng; Lin, Hsin; Hasan, M. Zahid 2016-02-01 Topological semimetals can support one-dimensional Fermi lines or zero-dimensional Weyl points in momentum space, where the valence and conduction bands touch. While the degeneracy points in Weyl semimetals are robust against any perturbation that preserves translational symmetry, nodal lines require protection by additional crystalline symmetries such as mirror reflection. Here we report, based on a systematic theoretical study and a detailed experimental characterization, the existence of topological nodal-line states in the non-centrosymmetric compound PbTaSe2 with strong spin-orbit coupling. Remarkably, the spin-orbit nodal lines in PbTaSe2 are not only protected by the reflection symmetry but also characterized by an integer topological invariant. Our detailed angle-resolved photoemission measurements, first-principles simulations and theoretical topological analysis illustrate the physical mechanism underlying the formation of the topological nodal-line states and associated surface states for the first time, thus paving the way towards exploring the exotic properties of the topological nodal-line fermions in condensed matter systems. 1. Preliminary Sensitivity Study of Upper Head Nodalization for LBLOCA in APR-1400 Energy Technology Data Exchange (ETDEWEB) Kang, Dong Gu; Yoo, Seung Hun; Cho, Dae-Hyung [Korea Institute of Nuclear Safety, Daejeon (Korea, Republic of) 2015-10-15 In this study, the key-way bypass was determined to be - 0.3 %. The steady state condition which is the initial condition for LBLOCA was obtained by MARS-KS calculation. Up to now, it was assumed that the temperature of the upper dome in APR-1400 was close to that of the cold leg. However, it was found that the temperature of the upper head/dome might be a little lower than or similar to that of the hot leg through the evaluation of the detailed design data. Since the higher upper head temperature affects blowdown quenching and peak cladding temperature in the reflood phase, the nodalization for upper head should be modified. In this study, the preliminary sensitivity study of original and modified nodalization for LBLOCA was performed, and the effect of upper head nodalization and temperature was evaluated qualitatively. In this study, the preliminary sensitivity study of original and modified nodalization for upper head in APR-1400 was performed, and the effect of upper head nodalization and temperature on LBLOCA PCT was evaluated qualitatively. Through the transient calculation, it was confirmed that the upper head temperature affects the water inventory in the upper head at the early stage of LBLOCA so it does the blowdown quenching and following reflood PCT significantly. The results in this study were caused by very conservative upper head temperature determination. 2. Topological nodal-line fermions in spin-orbit metal PbTaSe2. Science.gov (United States) Bian, Guang; Chang, Tay-Rong; Sankar, Raman; Xu, Su-Yang; Zheng, Hao; Neupert, Titus; Chiu, Ching-Kai; Huang, Shin-Ming; Chang, Guoqing; Belopolski, Ilya; Sanchez, Daniel S; Neupane, Madhab; Alidoust, Nasser; Liu, Chang; Wang, BaoKai; Lee, Chi-Cheng; Jeng, Horng-Tay; Zhang, Chenglong; Yuan, Zhujun; Jia, Shuang; Bansil, Arun; Chou, Fangcheng; Lin, Hsin; Hasan, M Zahid 2016-01-01 Topological semimetals can support one-dimensional Fermi lines or zero-dimensional Weyl points in momentum space, where the valence and conduction bands touch. While the degeneracy points in Weyl semimetals are robust against any perturbation that preserves translational symmetry, nodal lines require protection by additional crystalline symmetries such as mirror reflection. Here we report, based on a systematic theoretical study and a detailed experimental characterization, the existence of topological nodal-line states in the non-centrosymmetric compound PbTaSe2 with strong spin-orbit coupling. Remarkably, the spin-orbit nodal lines in PbTaSe2 are not only protected by the reflection symmetry but also characterized by an integer topological invariant. Our detailed angle-resolved photoemission measurements, first-principles simulations and theoretical topological analysis illustrate the physical mechanism underlying the formation of the topological nodal-line states and associated surface states for the first time, thus paving the way towards exploring the exotic properties of the topological nodal-line fermions in condensed matter systems. PMID:26829889 3. Nodalization effects on RELAP5 results related to MTR research reactor transient scenarios Directory of Open Access Journals (Sweden) Khedr Ahmed 2005-01-01 Full Text Available The present work deals with the anal y sis of RELAP5 results obtained from the evaluation study of the total loss of flow transient with the deficiency of the heat removal system in a research reactor using two different nodalizations. It focuses on the effect of nodalization on the thermal-hydraulic evaluation of the re search reactor. The analysis of RELAP5 results has shown that nodalization has a big effect on the predicted scenario of the postulated transient. There fore, great care should be taken during the nodalization of the reactor, especially when the avail able experimental or measured data are insufficient for making a complete qualification of the nodalization. Our analysis also shows that the research reactor pool simulation has a great effect on the evaluation of natural circulation flow and on other thermal-hydraulic parameters during the loss of flow transient. For example, the on set time of core boiling changes from less than 2000 s to 15000 s, starting from the beginning of the transient. This occurs if the pool is simulated by two vertical volumes in stead of one vertical volume. 4. Temporal and spatial requirements for Nodal-induced anterior mesendoderm and mesoderm in anterior neurulation. Science.gov (United States) Gonsar, Ngawang; Coughlin, Alicia; Clay-Wright, Jessica A; Borg, Bethanie R; Kindt, Lexy M; Liang, Jennifer O 2016-01-01 Zebrafish with defective Nodal signaling have a phenotype analogous to the fatal human birth defect anencephaly, which is caused by an open anterior neural tube. Previous work in our laboratory found that anterior open neural tube phenotypes in Nodal signaling mutants were caused by lack of mesendodermal/mesodermal tissues. Defects in these mutants are already apparent at neural plate stage, before the neuroepithelium starts to fold into a tube. Consistent with this, we found that the requirement for Nodal signaling maps to mid-late blastula stages. This timing correlates with the timing of prechordal plate mesendoderm and anterior mesoderm induction, suggesting these tissues act to promote neurulation. To further identify tissues important for neurulation, we took advantage of the variable phenotypes in Nodal signaling-deficient sqt mutant and Lefty1-overexpressing embryos. Statistical analysis indicated a strong, positive correlation between a closed neural tube and presence of several mesendoderm/mesoderm-derived tissues (hatching glands, cephalic paraxial mesoderm, notochord, and head muscles). However, the neural tube was closed in a subset of embryos that lacked any one of these tissues. This suggests that several types of Nodal-induced mesendodermal/mesodermal precursors are competent to promote neurulation. 5. Auxin controls local cytokinin biosynthesis in the nodal stem in apical dominance. Science.gov (United States) Tanaka, Mina; Takei, Kentaro; Kojima, Mikiko; Sakakibara, Hitoshi; Mori, Hitoshi 2006-03-01 In intact plants, the shoot apex grows predominantly and inhibits outgrowth of axillary buds. After decapitation of the shoot apex, outgrowth of axillary buds begins. This phenomenon is called an apical dominance. Although the involvement of auxin, which represses outgrowth of axillary buds, and cytokinin (CK), which promotes outgrowth of axillary buds, has been proposed, little is known about the underlying molecular mechanisms. In the present study, we demonstrated that auxin negatively regulates local CK biosynthesis in the nodal stem by controlling the expression level of the pea (Pisum sativum L.) gene adenosine phosphate-isopentenyltransferase (PsIPT), which encodes a key enzyme in CK biosynthesis. Before decapitation, PsIPT1 and PsIPT2 transcripts were undetectable; after decapitation, they were markedly induced in the nodal stem along with accumulation of CK. Expression of PsIPT was repressed by the application of indole-3-acetic acid (IAA). In excised nodal stem, PsIPT expression and CK levels also increased under IAA-free conditions. Furthermore, beta-glucuronidase expression, under the control of the PsIPT2 promoter region in transgenic Arabidopsis, was repressed by an IAA. Our results indicate that in apical dominance one role of auxin is to repress local biosynthesis of CK in the nodal stem and that, after decapitation, CKs, which are thought to be derived from the roots, are locally biosynthesized in the nodal stem rather than in the roots. PMID:16507092 6. Universal Cosmic Absolute and Modern Science Science.gov (United States) Kostro, Ludwik The official Sciences, especially all natural sciences, respect in their researches the principle of methodic naturalism i.e. they consider all phenomena as entirely natural and therefore in their scientific explanations they do never adduce or cite supernatural entities and forces. The purpose of this paper is to show that Modern Science has its own self-existent, self-acting, and self-sufficient Natural All-in Being or Omni-Being i.e. the entire Nature as a Whole that justifies the scientific methodic naturalism. Since this Natural All-in Being is one and only It should be considered as the own scientifically justified Natural Absolute of Science and should be called, in my opinion, the Universal Cosmic Absolute of Modern Science. It will be also shown that the Universal Cosmic Absolute is ontologically enormously stratified and is in its ultimate i.e. in its most fundamental stratum trans-reistic and trans-personal. It means that in its basic stratum. It is neither a Thing or a Person although It contains in Itself all things and persons with all other sentient and conscious individuals as well, On the turn of the 20th century the Science has begun to look for a theory of everything, for a final theory, for a master theory. In my opinion the natural Universal Cosmic Absolute will constitute in such a theory the radical all penetrating Ultimate Basic Reality and will substitute step by step the traditional supernatural personal Absolute. 7. Absolute calibration in vivo measurement systems International Nuclear Information System (INIS) Lawrence Livermore National Laboratory (LLNL) is currently investigating a new method for obtaining absolute calibration factors for radiation measurement systems used to measure internally deposited radionuclides in vivo. Absolute calibration of in vivo measurement systems will eliminate the need to generate a series of human surrogate structures (i.e., phantoms) for calibrating in vivo measurement systems. The absolute calibration of in vivo measurement systems utilizes magnetic resonance imaging (MRI) to define physiological structure, size, and composition. The MRI image provides a digitized representation of the physiological structure, which allows for any mathematical distribution of radionuclides within the body. Using Monte Carlo transport codes, the emission spectrum from the body is predicted. The in vivo measurement equipment is calibrated using the Monte Carlo code and adjusting for the intrinsic properties of the detection system. The calibration factors are verified using measurements of existing phantoms and previously obtained measurements of human volunteers. 8 refs 8. Quantum theory allows for absolute maximal contextuality Science.gov (United States) Amaral, Barbara; Cunha, Marcelo Terra; Cabello, Adán 2015-12-01 Contextuality is a fundamental feature of quantum theory and a necessary resource for quantum computation and communication. It is therefore important to investigate how large contextuality can be in quantum theory. Linear contextuality witnesses can be expressed as a sum S of n probabilities, and the independence number α and the Tsirelson-like number ϑ of the corresponding exclusivity graph are, respectively, the maximum of S for noncontextual theories and for the theory under consideration. A theory allows for absolute maximal contextuality if it has scenarios in which ϑ /α approaches n . Here we show that quantum theory allows for absolute maximal contextuality despite what is suggested by the examination of the quantum violations of Bell and noncontextuality inequalities considered in the past. Our proof is not constructive and does not single out explicit scenarios. Nevertheless, we identify scenarios in which quantum theory allows for almost-absolute-maximal contextuality. 9. Absolute photoacoustic thermometry in deep tissue. Science.gov (United States) Yao, Junjie; Ke, Haixin; Tai, Stephen; Zhou, Yong; Wang, Lihong V 2013-12-15 Photoacoustic thermography is a promising tool for temperature measurement in deep tissue. Here we propose an absolute temperature measurement method based on the dual temperature dependences of the Grüneisen parameter and the speed of sound in tissue. By taking ratiometric measurements at two adjacent temperatures, we can eliminate the factors that are temperature irrelevant but difficult to correct for in deep tissue. To validate our method, absolute temperatures of blood-filled tubes embedded ~9 mm deep in chicken tissue were measured in a biologically relevant range from 28°C to 46°C. The temperature measurement accuracy was ~0.6°C. The results suggest that our method can be potentially used for absolute temperature monitoring in deep tissue during thermotherapy. 10. COMPUTATION OF SUPER-CONVERGENT NODAL STRESSES OF TIMOSHENKO BEAM ELEMENTS BY EEP METHOD Institute of Scientific and Technical Information of China (English) 王枚; 袁驷 2004-01-01 The newly proposed element energy projection (EEP) method has been applied to the computation of super-convergent nodal stresses of Timoshenko beam elements. General formulas based on element projection theorem were derived and illustrative numerical examples using two typical elements were given. Both the analysis and examples show that EEP method also works very well for the problems with vector function solutions. The EEP method gives super-convergent nodal stresses, which are well comparable to the nodal displacements in terms of both convergence rate and error magnitude. And in addition, it can overcome the "shear locking" difficulty for stresses even when the displacements are badly affected. This research paves the way for application of the EEP method to general onedimensional systems of ordinary differential equations. 11. The role of nodal and internodal responses in gravitropism and autotropism in Galium aparine L Science.gov (United States) Heathcote, D. G.; Brown, A. H. (Principal Investigator) 1987-01-01 This time course and location of gravitropically induced curvatures in stems of goosegrass (Gallium aparine L.), a member of the Rubiaceae, have been investigated. In the early stages of the response (0-5 h), curvature develops throughout the growing region, and is followed by an autotropic straightening which affects the internodes only, leading to the production of essentially straight internodes some 15 h after the onset of gravistimulation. Curvatures developing in the nodal regions, however, continue to increase over this period, and are not subject to reversal by autotropism. The nodal curvatures are not entirely dependent on the presence of any other part of the plant, since marked curvatures can be induced in isolated nodal segments. This pattern of response leads ultimately to correction of the growth direction of the plant by means of curvature responses confined exclusively to the nodes, despite the initial participation of both nodes and internodes in the gravitropic reaction. 12. Zebrafish Rab5 proteins and a role for Rab5ab in nodal signalling. Science.gov (United States) Kenyon, Emma J; Campos, Isabel; Bull, James C; Williams, P Huw; Stemple, Derek L; Clark, Matthew D 2015-01-15 The RAB5 gene family is the best characterised of all human RAB families and is essential for in vitro homotypic fusion of early endosomes. In recent years, the disruption or activation of Rab5 family proteins has been used as a tool to understand growth factor signal transduction in whole animal systems such as Drosophila melanogaster and zebrafish. In this study we have examined the functions for four rab5 genes in zebrafish. Disruption of rab5ab expression by antisense morpholino oligonucleotide (MO) knockdown abolishes nodal signalling in early zebrafish embryos, whereas overexpression of rab5ab mRNA leads to ectopic expression of markers that are normally downstream of nodal signalling. By contrast MO disruption of other zebrafish rab5 genes shows little or no effect on expression of markers of dorsal organiser development. We conclude that rab5ab is essential for nodal signalling and organizer specification in the developing zebrafish embryo. 13. Absolute Stability And Hyperstability In Hilbert Space Science.gov (United States) Wen, John Ting-Yung 1989-01-01 Theorems on stabilities of feedback control systems proved. Paper presents recent developments regarding theorems of absolute stability and hyperstability of feedforward-and-feedback control system. Theorems applied in analysis of nonlinear, adaptive, and robust control. Extended to provide sufficient conditions for stability in system including nonlinear feedback subsystem and linear time-invariant (LTI) feedforward subsystem, state space of which is Hilbert space, and input and output spaces having finite numbers of dimensions. (In case of absolute stability, feedback subsystem memoryless and possibly time varying. For hyperstability, feedback system dynamical system.) 14. Absolute-Magnitude Distributions of Supernovae CERN Document Server Richardson, Dean; Wright, John; Maddox, Larry 2014-01-01 The absolute-magnitude distributions of seven supernova types are presented. The data used here were primarily taken from the Asiago Supernova Catalogue, but were supplemented with additional data. We accounted for both foreground and host-galaxy extinction. A bootstrap method is used to correct the samples for Malmquist bias. Separately, we generate volume-limited samples, restricted to events within 100 Mpc. We find that the superluminous events (M_B -15) make up about 3%. The normal Ia distribution was the brightest with a mean absolute blue magnitude of -19.25. The IIP distribution was the dimmest at -16.75. 15. Precise Measurement of the Absolute Fluorescence Yield Science.gov (United States) Ave, M.; Bohacova, M.; Daumiller, K.; Di Carlo, P.; di Giulio, C.; San Luis, P. Facal; Gonzales, D.; Hojvat, C.; Hörandel, J. R.; Hrabovsky, M.; Iarlori, M.; Keilhauer, B.; Klages, H.; Kleifges, M.; Kuehn, F.; Monasor, M.; Nozka, L.; Palatka, M.; Petrera, S.; Privitera, P.; Ridky, J.; Rizi, V.; D'Orfeuil, B. Rouille; Salamida, F.; Schovanek, P.; Smida, R.; Spinka, H.; Ulrich, A.; Verzi, V.; Williams, C. 2011-09-01 We present preliminary results of the absolute yield of fluorescence emission in atmospheric gases. Measurements were performed at the Fermilab Test Beam Facility with a variety of beam particles and gases. Absolute calibration of the fluorescence yield to 5% level was achieved by comparison with two known light sources--the Cherenkov light emitted by the beam particles, and a calibrated nitrogen laser. The uncertainty of the energy scale of current Ultra-High Energy Cosmic Rays experiments will be significantly improved by the AIRFLY measurement. 16. Sensitivity analysis of the RELAP5 nodalization to IPR-R1 TRIGA research reactor International Nuclear Information System (INIS) The main aim of this work is to identify how much the code results are affected by code user in the choice of, for example, the number of thermal-hydraulic channels in a nuclear reactor nodalization. To perform this, two essential modifications were made on a previous validated nodalization for analysis of steady state and forced recirculation off transient in the IPR-R1 TRIGA research reactor. Experimental data were taken as reference to compare the behavior of the reactor for two different types of model. The results found highlight the necessity of sensitivity analysis to obtain the ideal simulation model of a system. (author) 17. In Vitro Propagation of Desmodium gangeticum (L. DC. from Cotyledonary Nodal Explants Directory of Open Access Journals (Sweden) U R Vishwakarma 2009-01-01 Full Text Available An in vitro procedure for rapid multiplication of medicinally important plant Desmodium gangeticum (L. DC. (Fabaceae, has been developed using cotyledonary nodal explant. An average of 9.2 shoots per explant were obtained by culturing cotyledonary nodal explaint on Murashige and Skoog′s medium containing 8.8 μM BAP and 21.2 μM NAA, in combination, within 28 days. These shoots were rooted on half strength MS medium supplemented with IAA 17.1 μM. Rooted plantlets were hardened using 1:1:1 mixture of soil, river sand and vermiculite under green house conditions. 18. In Vitro Propagation of Desmodium gangeticum (L.) DC. from Cotyledonary Nodal Explants OpenAIRE U R Vishwakarma; Gurav, A M; Sharma, P.C 2009-01-01 An in vitro procedure for rapid multiplication of medicinally important plant Desmodium gangeticum (L.) DC. (Fabaceae), has been developed using cotyledonary nodal explant. An average of 9.2 shoots per explant were obtained by culturing cotyledonary nodal explaint on Murashige and Skoog′s medium containing 8.8 μM BAP and 21.2 μM NAA, in combination, within 28 days. These shoots were rooted on half strength MS medium supplemented with IAA 17.1 μM. Rooted plantlets were hardened using 1:1:1 mix... 19. Segmentation and Nodal Points in Narrative: Study of Multiple Variations of a Ballad CERN Document Server Murtagh, Fionn 2010-01-01 The Lady Maisry ballads afford us a framework within which to segment a storyline into its major components. Segments and as a consequence nodal points are discussed for nine different variants of the Lady Maisry story of a (young) woman being burnt to death by her family, on account of her becoming pregnant by a foreign personage. We motivate the importance of nodal points in textual and literary analysis. We show too how the openings of the nine variants can be analyzed comparatively, and also the conclusions of the ballads. 20. Average arterial input function for quantitative dynamic contrast enhanced magnetic resonance imaging of neck nodal metastases OpenAIRE Shukla-Dave, Amita; Lee, Nancy; Stambuk, Hilda; Wang, YA; Huang, Wei; Howard T Thaler; Patel, Snehal G.; Shah, Jatin P.; Koutcher, Jason A 2009-01-01 Background The present study determines the feasibility of generating an average arterial input function (Avg-AIF) from a limited population of patients with neck nodal metastases to be used for pharmacokinetic modeling of dynamic contrast-enhanced MRI (DCE-MRI) data in clinical trials of larger populations. Methods Twenty patients (mean age 50 years [range 27–77 years]) with neck nodal metastases underwent pretreatment DCE-MRI studies with a temporal resolution of 3.75 to 7.5 sec on a 1.5T c... 1. Synthesis, structure and masnetic properties of two new coordination polymers with carboxylate-substituted benzoimidazole lisands Institute of Scientific and Technical Information of China (English) HU BoWen; ZHAO JiongPeng; YANG Qian; ZHANG XiaoFeng; BU XianHe 2009-01-01 This paper reports two new coordination polymers formed by carboxylate-substituted benzoimidazole and formate ligands:[Mn(L)-(HCO2)]n (1) and [Co(L)·(HCO2)]n (2) (L = benzoimidazol-1-yl-acetate).Complexes 1 and 2 are isomorphous and adopt a new 3,6-connected three-nodal topology showing interesting magnetic properties:spin canted antiferromagnetism for Mn11 complex 1,but simple antiferromagnetic coupling for CoⅡ complex 2. 2. Synthesis, structure and magnetic properties of two new coordination polymers with carboxylate-substituted benzoimidazole ligands Institute of Scientific and Technical Information of China (English) 2009-01-01 This paper reports two new coordination polymers formed by carboxylate-substituted benzoimidazole and formate ligands: [Mn(L)·(HCO2)]n (1) and [Co(L)·(HCO2)]n (2) (L = benzoimidazol-1-yl-acetate). Com-plexes 1 and 2 are isomorphous and adopt a new 3,6-connected three-nodal topology showing inter-esting magnetic properties: spin canted antiferromagnetism for MnⅡ complex 1, but simple antiferro-magnetic coupling for CoⅡ complex 2. 3. Incidental Prophylactic Nodal Irradiation and Patterns of Nodal Relapse in Inoperable Early Stage NSCLC Patients Treated With SBRT: A Case-Matched Analysis Energy Technology Data Exchange (ETDEWEB) Lao, Louis [Department of Radiation Oncology, Princess Margaret Cancer Centre, University of Toronto, Toronto, Ontario (Canada); Department of Radiation Oncology, Auckland City Hospital, Auckland (New Zealand); Hope, Andrew J. [Department of Radiation Oncology, Princess Margaret Cancer Centre, University of Toronto, Toronto, Ontario (Canada); Maganti, Manjula [Department of Biostatistics, Princess Margaret Cancer Centre, University of Toronto, Toronto, Ontario (Canada); Brade, Anthony; Bezjak, Andrea; Saibishkumar, Elantholi P.; Giuliani, Meredith; Sun, Alexander [Department of Radiation Oncology, Princess Margaret Cancer Centre, University of Toronto, Toronto, Ontario (Canada); Cho, B. C. John, E-mail: john.cho@rmp.uhn.on.ca [Department of Radiation Oncology, Princess Margaret Cancer Centre, University of Toronto, Toronto, Ontario (Canada) 2014-09-01 Purpose: Reported rates of non-small cell lung cancer (NSCLC) nodal failure following stereotactic body radiation therapy (SBRT) are lower than those reported in the surgical series when matched for stage. We hypothesized that this effect was due to incidental prophylactic nodal irradiation. Methods and Materials: A prospectively collected group of medically inoperable early stage NSCLC patients from 2004 to 2010 was used to identify cases with nodal relapses. Controls were matched to cases, 2:1, controlling for tumor volume (ie, same or greater) and tumor location (ie, same lobe). Reference (normalized to equivalent dose for 2-Gy fractions [EQD2]) point doses at the ipsilateral hilum and carina, demographic data, and clinical outcomes were extracted from the medical records. Univariate conditional logistical regression analyses were performed with variables of interest. Results: Cases and controls were well matched except for size. The controls, as expected, had larger gross tumor volumes (P=.02). The mean ipsilateral hilar doses were 9.6 Gy and 22.4 Gy for cases and controls, respectively (P=.014). The mean carinal doses were 7.0 Gy and 9.2 Gy, respectively (P=.13). Mediastinal nodal relapses, with and without ipsilateral hilar relapse, were associated with mean ipsilateral hilar doses of 3.6 Gy and 19.8 Gy, respectively (P=.01). The conditional density plot appears to demonstrate an inverse dose-effect relationship between ipsilateral hilar normalized total dose and risk of ipsilateral hilar relapse. Conclusions: Incidental hilar dose greater than 20 Gy is significantly associated with fewer ipsilateral hilar relapses in inoperable early stage NSCLC patients treated with SBRT. 4. Det demokratiske argument for absolut ytringsfrihed DEFF Research Database (Denmark) Lægaard, Sune 2014-01-01 Artiklen diskuterer den påstand, at absolut ytringsfrihed er en nødvendig forudsætning for demokratisk legitimitet med udgangspunkt i en rekonstruktion af et argument fremsat af Ronald Dworkin. Spørgsmålet er, hvorfor ytringsfrihed skulle være en forudsætning for demokratisk legitimitet, og hvorf... 5. Time Function and Absolute Black Hole DEFF Research Database (Denmark) Javadi, Hossein; Forouzbakhsh, Farshid 2006-01-01 Einstein’s theory of gravity is not consistent with quantum mechanics, because general relativity cannot be quantized. [1] But without conversion of force and energy, it is impossible to find a grand unified theory. A very important result of CPH theory is time function that allows we give a new ...... description of absolute black hole and before the big bang.... 6. Teaching Absolute Value Inequalities to Mature Students Science.gov (United States) Sierpinska, Anna; Bobos, Georgeana; Pruncut, Andreea 2011-01-01 This paper gives an account of a teaching experiment on absolute value inequalities, whose aim was to identify characteristics of an approach that would realize the potential of the topic to develop theoretical thinking in students enrolled in prerequisite mathematics courses at a large, urban North American university. The potential is… 7. ABSOLUTE MEASUREMENT OF THE GANIL BEAM ENERGY NARCIS (Netherlands) CASANDJIAN, JM; MITTIG, W; BEUNARD, R; GAUDARD, L; LEPINESZILY, A; VILLARI, ACC; AUGER, G; BIANCHI, L; CUNSOLO, A; FOTI, A; LICHTENTHALER, R; PLAGNOL, E; SCHUTZ, Y; SIEMSSEN, RH; WIELECZKO, JP 1993-01-01 The energy of the GANIL cyclotron beam was measured on-line during the Pb-208 + Pb-208 elastic scattering experiment ''Search for Color van der Waals Force in the Pb-208 + Pb-208 Mott scattering'' with an absolute precision of 7 x 10(-5) at approximately 1.0 GeV, which represents an improvement of o 8. Stimulus Probability Effects in Absolute Identification Science.gov (United States) Kent, Christopher; Lamberts, Koen 2016-01-01 This study investigated the effect of stimulus presentation probability on accuracy and response times in an absolute identification task. Three schedules of presentation were used to investigate the interaction between presentation probability and stimulus position within the set. Data from individual participants indicated strong effects of… 9. Solving Absolute Value Equations Algebraically and Geometrically Science.gov (United States) Shiyuan, Wei 2005-01-01 The way in which students can improve their comprehension by understanding the geometrical meaning of algebraic equations or solving algebraic equation geometrically is described. Students can experiment with the conditions of the absolute value equation presented, for an interesting way to form an overall understanding of the concept. 10. Absolute-stability results in infinite dimensions NARCIS (Netherlands) Curtain, RF; Logemann, H; Staffans, O 2004-01-01 We derive absolute-stability results of Popov and circle-criterion type for infinite-dimensional systems in an input-output setting. Our results apply to feedback systems in which the linear part is the series interconnection of an input-output stable linear system and an integrator, and the nonline 11. Magnetoresistive sensor for absolute position detection NARCIS (Netherlands) Groenland, J.P.J. 1984-01-01 A digital measurement principle for absolute position is decscribed. The position data is recorded serially into a single track of a hard-magnetic layer with the help of longitudinal saturation recording. Detection is possible by means of an array of sensor elements which can be made of a substrate. 12. Thin-film magnetoresistive absolute position detector NARCIS (Netherlands) Groenland, Johannes Petrus Jacobus 1990-01-01 The subject of this thesis is the investigation of a digital absolute posi- tion-detection system, which is based on a position-information carrier (i.e. a magnetic tape) with one single code track on the one hand, and an array of magnetoresistive sensors for the detection of the informatio 13. Magnetoresistive transducer for absolute position detection NARCIS (Netherlands) Groenland, J.P.J. 1984-01-01 In this paper a new method is presented for the measurement of absolute linear or angular position. The digital position information is recorded serially into one track of a suitable hard-magnetic medium. The stray field of this information layer determines the angular magnetisation distribution in 14. Nodal Quasiparticle Meltdown in Ultra-High Resolution Pump-Probe Angle-Resolved Photoemission Energy Technology Data Exchange (ETDEWEB) Graf, Jeff; Jozwiak, Chris; Smallwood, Chris L.; Eisaki, H.; Kaindl, Robert A.; Lee, Dung-Hai; Lanzara, Alessandra 2011-06-03 High-T{sub c} cuprate superconductors are characterized by a strong momentum-dependent anisotropy between the low energy excitations along the Brillouin zone diagonal (nodal direction) and those along the Brillouin zone face (antinodal direction). Most obvious is the d-wave superconducting gap, with the largest magnitude found in the antinodal direction and no gap in the nodal direction. Additionally, while antin- odal quasiparticle excitations appear only below T{sub c}, superconductivity is thought to be indifferent to nodal excitations as they are regarded robust and insensitive to T{sub c}. Here we reveal an unexpected tie between nodal quasiparticles and superconductivity using high resolution time- and angle-resolved photoemission on optimally doped Bi{sub 2}Sr{sub 2}CaCu{sub 2}O{sub 8+{delta}} . We observe a suppression of the nodal quasiparticle spectral weight following pump laser excitation and measure its recovery dynamics. This suppression is dramatically enhanced in the superconducting state. These results reduce the nodal-antinodal dichotomy and challenge the conventional view of nodal excitation neutrality in superconductivity. The electronic structures of high-Tc cuprates are strongly momentum-dependent. This is one reason why the momentum-resolved technique of angle-resolved photoemission spectroscopy (ARPES) has been a central tool in the field of high-temperature superconductivity. For example, coherent low energy excitations with momenta near the Brillouin zone face, or antinodal quasiparticles (QPs), are only observed below T{sub c} and have been linked to superfluid density. They have therefore been the primary focus of ARPES studies. In contrast, nodal QPs, with momenta along the Brillouin zone diagonal, have received less attention and are usually regarded as largely immune to the superconducting transition because they seem insensitive to perturbations such as disorder, doping, isotope exchange, charge ordering, and temperature. Clearly 15. Finite-volume goal-oriented mesh adaptation for aerodynamics using functional derivative with respect to nodal coordinates Science.gov (United States) Todarello, Giovanni; Vonck, Floris; Bourasseau, Sébastien; Peter, Jacques; Désidéri, Jean-Antoine 2016-05-01 A new goal-oriented mesh adaptation method for finite volume/finite difference schemes is extended from the structured mesh framework to a more suitable setting for adaptation of unstructured meshes. The method is based on the total derivative of the goal with respect to volume mesh nodes that is computable after the solution of the goal discrete adjoint equation. The asymptotic behaviour of this derivative is assessed on regularly refined unstructured meshes. A local refinement criterion is derived from the requirement of limiting the first order change in the goal that an admissible node displacement may cause. Mesh adaptations are then carried out for classical test cases of 2D Euler flows. Efficiency and local density of the adapted meshes are presented. They are compared with those obtained with a more classical mesh adaptation method in the framework of finite volume/finite difference schemes [46]. Results are very close although the present method only makes usage of the current grid. 16. Does Tumor Depth Affect Nodal Upstaging in Squamous Cell Carcinoma of the Head and Neck? DEFF Research Database (Denmark) Alkureishi, Lee; Ross, Gary; Shoaib, Taimur; 2007-01-01 -eosin staining, SSS, and IHC. Patients upstaged by SSS/IHC were denoted pN1mi. RESULTS:: One hundred one of 172 patients were staged pN0, with 71 (41%) patients upstaged. Increasing tumor depth was associated with higher likelihood of upstaging (P positive correlation with nodal... 17. Automatic symbolic analysis of SC networks using a modified nodal approach NARCIS (Netherlands) Zivkovic, V.A.; Petkovic, P.M.; Milanovic, D.P. 1998-01-01 This paper presents a symbolic analysis of Switched-Capacitor (SC) circuits in the z-domain using Modified Nodal Approach (MNA). We have selected the MNA method as one of the widely established approaches in circuit analysis. The analyses are performed using SymsimC symbolic simulator which also ena 18. File list: NoD.ALL.05.AllAg.AllCell [Chip-atlas[Archive Lifescience Database Archive (English) Full Text Available NoD.ALL.05.AllAg.AllCell sacCer3 No description All cell types SRX826026,SRX826027,...RX332089,ERX585723 http://dbarchive.biosciencedbc.jp/kyushu-u/sacCer3/assembled/NoD.ALL.05.AllAg.AllCell.bed ... 19. On the Topology of Real Bundle Pairs over Nodal Symmetric Surfaces CERN Document Server Georgieva, Penka 2015-01-01 We give an alternative argument for the classification of real bundle pairs over smooth symmetric surfaces and extend this classification to nodal symmetric surfaces. We also classify the homotopy classes of automorphisms of real bundle pairs over symmetric surfaces. The two statements together describe the isomorphisms between real bundle pairs over symmetric surfaces up to deformation. 20. Radiation therapy for carcinoma of the hypopharynx with special reference to nodal control Energy Technology Data Exchange (ETDEWEB) Teshima, T.; Chatani, M.; Inoue, T.; Miyahara, H.; Sato, T. 1988-05-01 From October 1977 through December 1983, 61 patients with carcinoma of the hypopharynx were treated with radiation therapy (RT) and surgery or with RT alone. Five-year survival rates by N-stage, according to the TNM classification by UICC (1978), were 52% for N0 cases, 23% for N1, and 17% for N2-3 (N1 vs. N2-3, not significant). For N1-3 cases, corresponding figures by level of cervical nodal involvement by UICC (1978) were 29% for level 3 cases, 15% for level 2, and 8% for level 4 (level 3 vs. level 4, p less than 0.04). Therefore, the level of cervical nodal involvement was a more useful prognosticator for patients with nodal metastasis than the N-stage. Effective nodal control for patients with clinically positive nodes (N1-3) was obtained with a combination of neck node dissection and RT of 50 Gy or more. For N0 cases, elective RT of 50 Gy or more, encompassing an adequate field, was required. 1. Nodal Solutions for a Class of Fourth-Order Two-Point Boundary Value Problems OpenAIRE Xu Jia; Han XiaoLing 2010-01-01 We consider the fourth-order two-point boundary value problem , , , where is a parameter, is given constant, with on any subinterval of , satisfies for all , and , , for some . By using disconjugate operator theory and bifurcation techniques, we establish existence and multiplicity results of nodal solutions for the above problem. 2. Computation of Steady State Nodal Voltages for Fast Security Assessment in Power Systems DEFF Research Database (Denmark) Møller, Jakob Glarbo; Jóhannsson, Hjörtur; Østergaard, Jacob 2014-01-01 Development of a method for real-time assess-ment of post-contingency nodal voltages is introduced. Linear network theory is applied in an algorithm that utilizes Thevenin equivalent representation of power systems as seen from every voltage-controlled node in a network. The method is evaluated b... 3. Atrial activation during atrioventricular nodal reentrant tachycardia: Studies on retrograde fast pathway conduction NARCIS (Netherlands) D.G. Katritsis; K.A. Ellenbogen; A.E. Becker 2006-01-01 BACKGROUND Detailed right and left septal mapping of retrograde atrial activation during typical atrioventricutar nodal reentrant tachycardia (AVNRT) has not been undertaken and may provide insight into the complex physiology of AVNRT, especially the anatomic localization of the fast and stow pathwa 4. A nodal spectral stiffness matrix for the finite-element method Science.gov (United States) Bittencourt, Marco L.; Vazquez, Thais G. 2008-12-01 In this paper, shape functions are proposed for the spectral finite-element method aiming to finding a nodal spectral stiffness matrix. The proposed shape functions obtain a nearly diagonal 1D stiffness matrix with better conditioning than using the Lagrange and Jacobi bases. 5. Electrophysiologic and antiarrhythmic effects of intravenous bisoprolol in atrioventricular nodal reentry tachycardia NARCIS (Netherlands) vandeVen, LLM; Crijns, HJGM; deMuinck, ED; VanGelder, IC; VanWijk, LM; Lie, KI 1996-01-01 Beta-blockade may be useful in the termination and prevention of atrioventricular nodal reentry tachycardia (AVNRT), An electrophysiologic study was performed in 9 patients (4 men and 5 women; mean +/- SD age, 56 +/- 16 years) with documented AVNRT before and after the intravenous administration of 6. File list: NoD.ALL.50.NA.AllCell [Chip-atlas[Archive Lifescience Database Archive (English) Full Text Available NoD.ALL.50.NA.AllCell ce10 No description NA All cell types SRX216757,SRX216759,SRX...RX278067,SRX278070 http://dbarchive.biosciencedbc.jp/kyushu-u/ce10/assembled/NoD.ALL.50.NA.AllCell.bed ... 7. File list: NoD.ALL.50.NA.AllCell [Chip-atlas[Archive Lifescience Database Archive (English) Full Text Available NoD.ALL.50.NA.AllCell dm3 No description NA All cell types ERX102368,ERX242709,ERX0...,SRX231909,ERX242710,SRX229433,SRX231857,ERX242714,ERX242725,ERX242715 http://dbarchive.biosciencedbc.jp/kyushu-u/dm3/assembled/NoD.ALL.50.NA.AllCell.bed ... 8. Analysis of nodal aberration properties in off-axis freeform system design. Science.gov (United States) Shi, Haodong; Jiang, Huilin; Zhang, Xin; Wang, Chao; Liu, Tao 2016-08-20 Freeform surfaces have the advantage of balancing off-axis aberration. In this paper, based on the framework of nodal aberration theory (NAT) applied to the coaxial system, the third-order astigmatism and coma wave aberration expressions of an off-axis system with Zernike polynomial surfaces are derived. The relationship between the off-axis and surface shape acting on the nodal distributions is revealed. The nodal aberration properties of the off-axis freeform system are analyzed and validated by using full-field displays (FFDs). It has been demonstrated that adding Zernike terms, up to nine, to the off-axis system modifies the nodal locations, but the field dependence of the third-order aberration does not change. On this basis, an off-axis two-mirror freeform system with 500 mm effective focal length (EFL) and 300 mm entrance pupil diameter (EPD) working in long-wave infrared is designed. The field constant aberrations induced by surface tilting are corrected by selecting specific Zernike terms. The design results show that the nodes of third-order astigmatism and coma move back into the field of view (FOV). The modulation transfer function (MTF) curves are above 0.4 at 20 line pairs per millimeter (lp/mm) which meets the infrared reconnaissance requirement. This work provides essential insight and guidance for aberration correction in off-axis freeform system design. PMID:27557003 9. Static and dynamic posterior cingulate cortex nodal topology of default mode network predicts attention task performance. Science.gov (United States) Lin, Pan; Yang, Yong; Jovicich, Jorge; De Pisapia, Nicola; Wang, Xiang; Zuo, Chun S; Levitt, James Jonathan 2016-03-01 Characterization of the default mode network (DMN) as a complex network of functionally interacting dynamic systems has received great interest for the study of DMN neural mechanisms. In particular, understanding the relationship of intrinsic resting-state DMN brain network with cognitive behaviors is an important issue in healthy cognition and mental disorders. However, it is still unclear how DMN functional connectivity links to cognitive behaviors during resting-state. In this study, we hypothesize that static and dynamic DMN nodal topology is associated with upcoming cognitive task performance. We used graph theory analysis in order to understand better the relationship between the DMN functional connectivity and cognitive behavior during resting-state and task performance. Nodal degree of the DMN was calculated as a metric of network topology. We found that the static and dynamic posterior cingulate cortex (PCC) nodal degree within the DMN was associated with task performance (Reaction Time). Our results show that the core node PCC nodal degree within the DMN was significantly correlated with reaction time, which suggests that the PCC plays a key role in supporting cognitive function. PMID:25904156 10. Weak point property and sections of Picard bundles on a compactified Jacobian over a nodal curve Indian Academy of Sciences (India) USHA N BHOSLE; SANJAY SINGH 2016-08-01 We show that the compactified Jacobian (and its desingularization) of an integral nodal curve$Y$satisfies the weak point property and the Jacobian of$Y$satisfies the diagonal property. We compute some cohomologies of Picard bundles on the compactified Jacobian and its desingularization 11. Molecular Characterization and Patient Outcome of Melanoma Nodal Metastases and an Unknown Primary Site NARCIS (Netherlands) A. Gos (Aleksandra); M. Jurkowska (Monika); A.C.J. van Akkooi (Alexander); C. Robert (Caroline); H. Kosela-Paterczyk (Hanna); S. Koljenovic (Senada); N. Kamsukom (Nyam); W. Michej (Wanda); A. Jeziorski (Arkadiusz); P. Pluta (Piotr); C. Verhoef (Cornelis); J.A. Siedlecki (Janusz); A.M.M. Eggermont (Alexander); P. Rutkowski (Piotr) 2014-01-01 textabstractBackground Melanoma of unknown primary site (MUP) is not a completely understood entity with nodal metastases as the most common first clinical manifestation. The aim of this multicentric study was to assess frequency and type of oncogenic BRAF/NRAS/KIT mutations in MUP with clinically d 12. A difference-equation formalism for the nodal domains of separable billiards Science.gov (United States) Manjunath, Naren; Samajdar, Rhine; Jain, Sudhir R. 2016-09-01 Recently, the nodal domain counts of planar, integrable billiards with Dirichlet boundary conditions were shown to satisfy certain difference equations in Samajdar and Jain (2014). The exact solutions of these equations give the number of domains explicitly. For complete generality, we demonstrate this novel formulation for three additional separable systems and thus extend the statement to all integrable billiards. 13. Depletion Calculations for MTR Core Using MCNPX and Multi-Group Nodal Diffusion Methods Energy Technology Data Exchange (ETDEWEB) Jaradata, Mustafa K. [Univ. of Science and Technology, Daejeon (Korea, Republic of); Park, Chang Je; Lee, Byungchul [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of) 2013-10-15 In order to maintain a self-sustaining steady-state chain reaction, more fuel than is necessary in order to maintain a steady state chain reaction must be loaded. The introduction of this excess fuel increases the net multiplication capability of the system. In this paper MCNPX and multi-group nodal diffusion theory will be used for depletion calculations for MTR core. The eigenvalue and power distribution in the core will be compared for different burnup. Multi-group nodal diffusion theory with combination of NEWT-TRITON system was used to perform depletion calculations for 3Χ3 MTR core. 2G and 6G approximations were used and compared with MCNPX results for 2G approximation the maximum difference from MCNPX was 40 mk and for 6G approximation was 6 mk which is comparable to the MCNPX results. The calculated power using nodal code was almost the same MCNPX results. Finally the results of the multi-group nodal theory were acceptable and comparable to the calculated using MCNPX. 14. Coordinate System And Coordinate Transformations Based On Wave Nature Of Light CERN Document Server Yagan, M F 2006-01-01 The Classical Coordinate System is geometrical by nature with time being an external variable. Constructing a classical coordinate system employs a point-like signal with infinite speed. In Special Relativity Theory the speed is limited but the signal is a point-like particle (photon). If the oscillatory nature of light is considered, an event in absolute space is to be characterized by three coordinates namely, distance, time and phase. The Galilean transformation equations for space and time coordinates should be complemented by a third equation that accounts for the phase transformation. Wave equation remains invariant under such transformation and kinematical equivalence of inertial reference frames is conserved. Lorentz transforms apply to wave length and wave period of the exchanged light signal in a dynamic set-up. 15. An absolute measure for a key currency Science.gov (United States) Oya, Shunsuke; Aihara, Kazuyuki; Hirata, Yoshito It is generally considered that the US dollar and the euro are the key currencies in the world and in Europe, respectively. However, there is no absolute general measure for a key currency. Here, we investigate the 24-hour periodicity of foreign exchange markets using a recurrence plot, and define an absolute measure for a key currency based on the strength of the periodicity. Moreover, we analyze the time evolution of this measure. The results show that the credibility of the US dollar has not decreased significantly since the Lehman shock, when the Lehman Brothers bankrupted and influenced the economic markets, and has increased even relatively better than that of the euro and that of the Japanese yen. 16. An approach to model reactor core nodalization for deterministic safety analysis Energy Technology Data Exchange (ETDEWEB) Salim, Mohd Faiz, E-mail: mohdfaizs@tnb.com.my; Samsudin, Mohd Rafie, E-mail: rafies@tnb.com.my [Nuclear Energy Department, Regulatory Economics & Planning Division, Tenaga Nasional Berhad (Malaysia); Mamat Ibrahim, Mohd Rizal, E-mail: m-rizal@nuclearmalaysia.gov.my [Prototypes & Plant Development Center, Malaysian Nuclear Agency (Malaysia); Roslan, Ridha, E-mail: ridha@aelb.gov.my; Sadri, Abd Aziz [Nuclear Installation Divisions, Atomic Energy Licensing Board (Malaysia); Farid, Mohd Fairus Abd [Reactor Technology Center, Malaysian Nuclear Agency (Malaysia) 2016-01-22 Adopting good nodalization strategy is essential to produce an accurate and high quality input model for Deterministic Safety Analysis (DSA) using System Thermal-Hydraulic (SYS-TH) computer code. The purpose of such analysis is to demonstrate the compliance against regulatory requirements and to verify the behavior of the reactor during normal and accident conditions as it was originally designed. Numerous studies in the past have been devoted to the development of the nodalization strategy for small research reactor (e.g. 250kW) up to the bigger research reactor (e.g. 30MW). As such, this paper aims to discuss the state-of-arts thermal hydraulics channel to be employed in the nodalization for RTP-TRIGA Research Reactor specifically for the reactor core. At present, the required thermal-hydraulic parameters for reactor core, such as core geometrical data (length, coolant flow area, hydraulic diameters, and axial power profile) and material properties (including the UZrH{sub 1.6}, stainless steel clad, graphite reflector) have been collected, analyzed and consolidated in the Reference Database of RTP using standardized methodology, mainly derived from the available technical documentations. Based on the available information in the database, assumptions made on the nodalization approach and calculations performed will be discussed and presented. The development and identification of the thermal hydraulics channel for the reactor core will be implemented during the SYS-TH calculation using RELAP5-3D{sup ®} computer code. This activity presented in this paper is part of the development of overall nodalization description for RTP-TRIGA Research Reactor under the IAEA Norwegian Extra-Budgetary Programme (NOKEBP) mentoring project on Expertise Development through the Analysis of Reactor Thermal-Hydraulics for Malaysia, denoted as EARTH-M. 17. The impact of nodal tumour burden on lymphoscintigraphic imaging in patients with melanomas Energy Technology Data Exchange (ETDEWEB) Kretschmer, Lutz; Bertsch, Hans Peter; Hellriegel, Simin; Thoms, Kai-Martin; Schoen, Michael Peter [Georg August University of Goettingen, Department of Dermatology, Venereology and Allergology, Goettingen (Germany); Bardzik, Pawel; Meller, Johannes; Sahlmann, Carsten Oliver [Georg-August-University of Goettingen, Department of Nuclear Medicine, Goettingen (Germany) 2014-10-15 To retrospectively study the influence of nodal tumour burden on lymphoscintigraphic imaging in 509 consecutive patients with melanomas. Bidirectional lymphatic drainage, the clear depiction of an afferent lymphatic vessel, time to depiction of the first sentinel lymph node (SLN) and number of depicted and excised nodes were recorded. Nodal tumour load was classified as SLN-negative, SLN micrometastases or macrometastases. In the overall population, using multivariate regression analysis, a short SLN depiction time was significantly associated with the depiction of a greater number of radioactive nodes, a short distance between the primary tumour site and the nodal basin, younger age and lower nodal tumour burden. The proportion of patients with clear depiction of an afferent lymphatic vessel depended on the nodal tumour load (46 % in SLN-negative patients, 57 % in SLN positive patients, and 69 % in patients with macrometastases; P = 0.009). Macrometastasis was significantly associated with delayed depiction of the first radioactive node and a greater number of depicted hotspots. In patients with clinically nonsuspicious nodes, i.e. the classical target group for SLN biopsy, clear depiction of an afferent vessel was significantly associated with a higher number of SLNs during dynamic acquisition, SLN micrometastasis and a higher overall number of metastatic lymph nodes after SLN biopsy plus completion lymphadenectomy. The excision of more than two SLNs did not increase the metastasis detection rate. In patients with bidirectional or tridirectional lymphatic drainage, the SLN positivity rates for the first, second and third basin were 25.4 %, 11.7 % and 0.0 %, respectively (P = 0.002). In patients with clinically nonsuspicious lymph nodes, clear depiction of an afferent lymph vessel may be a sign of micrometastasis. Macrometastasis is associated with prominent afferent vessels, delayed depiction of the first radioactive node and a higher number of depicted hotspots 18. An approach to model reactor core nodalization for deterministic safety analysis Science.gov (United States) Salim, Mohd Faiz; Samsudin, Mohd Rafie; Mamat @ Ibrahim, Mohd Rizal; Roslan, Ridha; Sadri, Abd Aziz; Farid, Mohd Fairus Abd 2016-01-01 Adopting good nodalization strategy is essential to produce an accurate and high quality input model for Deterministic Safety Analysis (DSA) using System Thermal-Hydraulic (SYS-TH) computer code. The purpose of such analysis is to demonstrate the compliance against regulatory requirements and to verify the behavior of the reactor during normal and accident conditions as it was originally designed. Numerous studies in the past have been devoted to the development of the nodalization strategy for small research reactor (e.g. 250kW) up to the bigger research reactor (e.g. 30MW). As such, this paper aims to discuss the state-of-arts thermal hydraulics channel to be employed in the nodalization for RTP-TRIGA Research Reactor specifically for the reactor core. At present, the required thermal-hydraulic parameters for reactor core, such as core geometrical data (length, coolant flow area, hydraulic diameters, and axial power profile) and material properties (including the UZrH1.6, stainless steel clad, graphite reflector) have been collected, analyzed and consolidated in the Reference Database of RTP using standardized methodology, mainly derived from the available technical documentations. Based on the available information in the database, assumptions made on the nodalization approach and calculations performed will be discussed and presented. The development and identification of the thermal hydraulics channel for the reactor core will be implemented during the SYS-TH calculation using RELAP5-3D® computer code. This activity presented in this paper is part of the development of overall nodalization description for RTP-TRIGA Research Reactor under the IAEA Norwegian Extra-Budgetary Programme (NOKEBP) mentoring project on Expertise Development through the Analysis of Reactor Thermal-Hydraulics for Malaysia, denoted as EARTH-M. 19. An approach to model reactor core nodalization for deterministic safety analysis International Nuclear Information System (INIS) Adopting good nodalization strategy is essential to produce an accurate and high quality input model for Deterministic Safety Analysis (DSA) using System Thermal-Hydraulic (SYS-TH) computer code. The purpose of such analysis is to demonstrate the compliance against regulatory requirements and to verify the behavior of the reactor during normal and accident conditions as it was originally designed. Numerous studies in the past have been devoted to the development of the nodalization strategy for small research reactor (e.g. 250kW) up to the bigger research reactor (e.g. 30MW). As such, this paper aims to discuss the state-of-arts thermal hydraulics channel to be employed in the nodalization for RTP-TRIGA Research Reactor specifically for the reactor core. At present, the required thermal-hydraulic parameters for reactor core, such as core geometrical data (length, coolant flow area, hydraulic diameters, and axial power profile) and material properties (including the UZrH1.6, stainless steel clad, graphite reflector) have been collected, analyzed and consolidated in the Reference Database of RTP using standardized methodology, mainly derived from the available technical documentations. Based on the available information in the database, assumptions made on the nodalization approach and calculations performed will be discussed and presented. The development and identification of the thermal hydraulics channel for the reactor core will be implemented during the SYS-TH calculation using RELAP5-3D® computer code. This activity presented in this paper is part of the development of overall nodalization description for RTP-TRIGA Research Reactor under the IAEA Norwegian Extra-Budgetary Programme (NOKEBP) mentoring project on Expertise Development through the Analysis of Reactor Thermal-Hydraulics for Malaysia, denoted as EARTH-M 20. Absolute Parallelism Geometry: Developments, Applications and Problems OpenAIRE Wanas, M. I. 2002-01-01 Absolute parallelism geometry is frequently used for physical applications. It has two main defects, from the point of view of applications. The first is the identical vanishing of its curvature tensor. The second is that its autoparallel paths do not represent physical trajectories. The present work shows how these defects were treated in the course of development of the geometry. The new version of this geometry contains simultaneous non-vanishing torsion and curvatures. Also, the new paths... 1. Cosmological frames for theories with absolute parallelism OpenAIRE Ferraro, Rafael; Fiorini, Franco 2011-01-01 The vierbein (tetrad) fields for closed and open Friedmann-Robertson-Walker cosmologies are hard to work out in most of the theories featuring absolute parallelism. The difficulty is traced in the fact that these theories are not invariant under local Lorentz transformations of the vierbein. We illustrate this issue in the framework of f(T) theories and Born-Infeld determinantal gravity. In particular, we show that the early Universe as described by the Born-Infeld scheme is singularity free ... 2. The absolute differential calculus (calculus of tensors) CERN Document Server Levi-Civita, Tullio 2013-01-01 Written by a towering figure of twentieth-century mathematics, this classic examines the mathematical background necessary for a grasp of relativity theory. Tullio Levi-Civita provides a thorough treatment of the introductory theories that form the basis for discussions of fundamental quadratic forms and absolute differential calculus, and he further explores physical applications.Part one opens with considerations of functional determinants and matrices, advancing to systems of total differential equations, linear partial differential equations, algebraic foundations, and a geometrical intro 3. Absolute clock synchronisation and special relativity paradoxes OpenAIRE Ciborowski, Jacek; Wlodarczyk, Marta 2012-01-01 Solving special relativity paradoxes requires rigorous analysis of event timing, due to relative simultaneity in consequence of the Lorentz transformation. Since clock synchronisation is a convention in special theory of relativity, instead of the Einstein's procedure one may choose such that offers absolute simultaneity. We present in short the corresponding formalism in one spatial dimension. We show that paradoxes do not arise with this choice of synchronisation and descriptions of these i... 4. Absolute distance metrology for space interferometers OpenAIRE Swinkels, B L; Bhattacharya, N; Wielders, A.A.; Braat, J.J.M. 2005-01-01 Future space missions, among which the Darwin Space Interferometer, will consist of several free flying satellites. A complex metrology system is required to have all the components fly accurately in formation and have it operate as a single instrument. Our work focuses on a possible implementation of the sub-system that measures the absolute distance between two satellites with high accuracy. For Darwin the required accuracy is on the order of 70 micrometer over a distance of 250 meter. We a... 5. Measurement of absolute gravity acceleration in Firenze Directory of Open Access Journals (Sweden) M. de Angelis 2011-01-01 Full Text Available This paper reports the results from the accurate measurement of the acceleration of gravity g taken at two separate premises in the Polo Scientifico of the University of Firenze (Italy. In these laboratories, two separate experiments aiming at measuring the Newtonian constant and testing the Newtonian law at short distances are in progress. Both experiments require an independent knowledge on the local value of g. The only available datum, pertaining to the italian zero-order gravity network, was taken more than 20 years ago at a distance of more than 60 km from the study site. Gravity measurements were conducted using an FG5 absolute gravimeter, and accompanied by seismic recordings for evaluating the noise condition at the site. The absolute accelerations of gravity at the two laboratories are (980 492 160.6 ± 4.0 μGal and (980 492 048.3 ± 3.0 μGal for the European Laboratory for Non-Linear Spectroscopy (LENS and Dipartimento di Fisica e Astronomia, respectively. Other than for the two referenced experiments, the data here presented will serve as a benchmark for any future study requiring an accurate knowledge of the absolute value of the acceleration of gravity in the study region. 6. Measurement of absolute gravity acceleration in Firenze Science.gov (United States) de Angelis, M.; Greco, F.; Pistorio, A.; Poli, N.; Prevedelli, M.; Saccorotti, G.; Sorrentino, F.; Tino, G. M. 2011-01-01 This paper reports the results from the accurate measurement of the acceleration of gravity g taken at two separate premises in the Polo Scientifico of the University of Firenze (Italy). In these laboratories, two separate experiments aiming at measuring the Newtonian constant and testing the Newtonian law at short distances are in progress. Both experiments require an independent knowledge on the local value of g. The only available datum, pertaining to the italian zero-order gravity network, was taken more than 20 years ago at a distance of more than 60 km from the study site. Gravity measurements were conducted using an FG5 absolute gravimeter, and accompanied by seismic recordings for evaluating the noise condition at the site. The absolute accelerations of gravity at the two laboratories are (980 492 160.6 ± 4.0) μGal and (980 492 048.3 ± 3.0) μGal for the European Laboratory for Non-Linear Spectroscopy (LENS) and Dipartimento di Fisica e Astronomia, respectively. Other than for the two referenced experiments, the data here presented will serve as a benchmark for any future study requiring an accurate knowledge of the absolute value of the acceleration of gravity in the study region. 7. Nodal signaling is required for mesodermal and ventral but not for dorsal fates in the indirect developing hemichordate, Ptychodera flava Directory of Open Access Journals (Sweden) Eric Röttinger 2015-07-01 Full Text Available Nodal signaling plays crucial roles in vertebrate developmental processes such as endoderm and mesoderm formation, and axial patterning events along the anteroposterior, dorsoventral and left-right axes. In echinoderms, Nodal plays an essential role in the establishment of the dorsoventral axis and left-right asymmetry, but not in endoderm or mesoderm induction. In protostomes, Nodal signaling appears to be involved only in establishing left-right asymmetry. Hence, it is hypothesized that Nodal signaling has been co-opted to pattern the dorsoventral axis of deuterostomes and for endoderm, mesoderm formation as well as anteroposterior patterning in chordates. Hemichordata, together with echinoderms, represent the sister taxon to chordates. In this study, we analyze the role of Nodal signaling in the indirect developing hemichordate Ptychodera flava. In particular, we show that during gastrulation nodal transcripts are detected in a ring of cells at the vegetal pole that gives rise to endomesoderm and in the ventral ectoderm at later stages of development. Inhibition of Nodal function disrupts dorsoventral fates and also blocks formation of the larval mesoderm. Interestingly, molecular analysis reveals that only mesodermal, apical and ventral gene expression is affected while the dorsal side appears to be patterned correctly. Taken together, this study suggests that the co-option of Nodal signaling in mesoderm formation and potentially in anteroposterior patterning has occurred prior to the emergence of chordates and that Nodal signaling on the ventral side is uncoupled from BMP signaling on the dorsal side, representing a major difference from the molecular mechanisms of dorsoventral patterning events in echinoderms. 8. Optimized coordinates for anharmonic vibrational structure theories. Science.gov (United States) Yagi, Kiyoshi; Keçeli, Murat; Hirata, So 2012-11-28 A procedure to determine optimal vibrational coordinates is developed on the basis of an earlier idea of Thompson and Truhlar [J. Chem. Phys. 77, 3031 (1982)]. For a given molecule, these coordinates are defined as the unitary transform of the normal coordinates that minimizes the energy of the vibrational self-consistent-field (VSCF) method for the ground state. They are justified by the fact that VSCF in these coordinates becomes exact in two limiting cases: harmonic oscillators, where the optimized coordinates are normal, and noninteracting anharmonic oscillators, in which the optimized coordinates are localized on individual oscillators. A robust and general optimization algorithm is developed, which decomposes the transformation matrix into a product of Jacobi matrices, determines the rotation angle of each Jacobi matrix that minimizes the energy, and iterates the process until a minimum in the whole high dimension is reached. It is shown that the optimized coordinates are neither entirely localized nor entirely delocalized (or normal) in any of the molecules (the water, water dimer, and ethylene molecules) examined (apart from the aforementioned limiting cases). Rather, high-frequency stretching modes tend to be localized, whereas low-frequency skeletal vibrations remain normal. On the basis of these coordinates, we introduce two new vibrational structure methods: optimized-coordinate VSCF (oc-VSCF) and optimized-coordinate vibrational configuration interaction (oc-VCI). For the modes that become localized, oc-VSCF is found to outperform VSCF, whereas, for both classes of modes, oc-VCI exhibits much more rapid convergence than VCI with respect to the rank of excitations. We propose a rational configuration selection for oc-VCI when the optimized coordinates are localized. The use of the optimized coordinates in VCI with this configuration selection scheme reduces the mean absolute errors in the frequencies of the fundamentals and the first overtones 9. Mapping of selected markets with Nodal pricing or similar systems. Australia, New Zealand and North American power markets Energy Technology Data Exchange (ETDEWEB) Mathiesen, Vivi (ed.) 2011-07-01 This report shows that the principals of nodal pricing can be implemented in different ways. A common denominator for markets with nodal pricing is a central market based nodal dispatch, where prices and flows are determined simultaneously close to real time. This stands apart from the European market design, which is based on a highly simplified version of the grid, and a physical point auction day ahead. Congestion management is handled by the TSO during the operational hour and not through the market as is the case in nodal pricing systems. Nodal pricing yields optimal dispatch and congestion management through the market, and as such an optimal utilisation of energy generation and network. However, whether this short term optimisation delivers the highest overall efficiency for the market in terms of competition in the wholesale and retail market, price discovery, possibilities for hedging, long term price signals etc. is difficult to determine. The markets investigated handle issues such as market power, risk management, investment signals and retail markets in very different ways. New Zealand and PJM are examples of markets with full nodal pricing, i.e. both generators and the demand side are exposed to nodal prices. The PJM market has more 'additional features' than the New Zealand market. Examples of these are separate capacity market to trigger investments in generation and generator price caps to deal with situations of market power. In addition PJM offers liquid and mature markets for risk management, such as aggregates of nodes where market participant can chose to be settled (rather than to be settled directly at the node). A general finding though, seems to be that risk management at peripheral nodes is challenging in nodal markets, particularly for independent retailers. In New Zealand generators and retailers were permitted to 'reintegrate' in order to cope with the nodal prices. The Australian market has central market based 10. Regeneration of three sweet potato (Ipomea batatas (L.)) accessions via meristem, Nodal and callus induction International Nuclear Information System (INIS) In vitro regeneration of three sweet potato accessions UE007, UK-BNARI and SA-BNARI using meristem, nodal cuttings or callus induction was studied. Meristematic explants cultured on Murashige and Skoog (1962) basal medium supplemented with low concentration of benzylaminopurine (BAP) or kinetin resulted in callus with or without shoot development which delayed shoot emergence. The degree of callus development increased as the concentration of the cytokinin in the culture medium increased. Although, callus development was comparatively lower on kinetin amended medium than BAP amended medium, Murashige and Skoog medium supplemented with 0.25mg/1BAP had the highest shoot induction (80%). For further differentiation of callus or shoots into distinct stem and leaves, the culture were transferred into fresh MS medium supplemented with 0.25mg/1 BAP, 0.1 mg/1 NAA and 0.1 mg/1 Gibberellic acid (GA3. To overcome the delay in shoot initiation using meristem culture, nodal cuttings of sweet potato were used as explants and cultured on MS medium amended with 0.3 - 0.9mg/1 BAP. All explants cultured on 0.3 or 0.6mg/1 BAP developed shoots. Furthermore, liquid MS medium amended with 0.25mg/1 BAP, 0.1mg/I NAA, and 0.1mg/1 GA3 also enhanced early shoot development from nodal cutting explants compared to solid culture. Post flask acclimatisation of meristem or nodal cutting-derived plantlets showed that meristem derived plantlets were better acclimatised than nodal cutting plants due to vigorous root development leading to higher percentage survival in pots and subsequent tuber production. Callusogenesis was achieved when leaf lobe explants were cultured on CLC/ Ipomoea medium supplemented with 1.0 - 4.0mg/1 2,4-D with 4.0mg/1 2,4-D being the optimal concentration. However, the calli were non-embryogenic and therefore could not produce embryos when transferred to 0.1mg/1 BAP amended medium but rather produced either single or multiple shoots. The highest percentage shoot (83.3%) was 11. A variational nodal expansion method for the solution of multigroup neutron diffusion equations International Nuclear Information System (INIS) An accurate neutronics analysis method is needed for light water reactor core monitoring systems to efficiently operate the core with a smaller margin to limiting parameters. It is also required in in-core fuel management systems to optimize the core loading patterns, and the fuel designs with a higher reliability. When mixed oxide fuel or much higher burnup fuel is used, a new higher order nodal method seems necessary to introduce. Based on these considerations, a new nodal diffusion method for the neutronics analysis of light water reactor cores has been developed. The method is based on an approximation of neutron fluxes by expanding them with a set of functions defined within a node. The expansion coefficients are determined in such a way that the solution becomes the most accurate approximation to the exact solution by utilizing the variational principle. The expansion functions are obtained only from single assembly diffusion calculations. The present method includes no homogenization procedure, and the assembly heterogeneity effect on neutron fluxes is taken into account in a consistent way. The intra-nodal pin-power distribution can also be determined in a consistent way with high accuracy. The present method was implemented in a two-dimensional nodal code, and tested for benchmark cases. The results proved that the accuracy of the present method was excellent. The root mean square errors of both nodal powers and nodal maximum pin powers were observed to be less than 1%. The computing time of the code was measured to be about 3% of the reference, fine-mesh calculation. A three-dimensional version is currently being developed, and since the heterogeneity effect is of less importance in axial direction, a more efficient calculation method can be adopted for the axial solution of the neutron flux. The new method can be used as a ''plug-in'' module to existing core simulators to increase the accuracy of the neutronics part of existing core models, including the 12. Absolute calibration of the Auger fluorescence detectors Energy Technology Data Exchange (ETDEWEB) Bauleo, P.; Brack, J.; Garrard, L.; Harton, J.; Knapik, R.; Meyhandan, R.; Rovero, A.C.; /Buenos Aires, IAFE; Tamashiro, A.; Warner, D. 2005-07-01 Absolute calibration of the Pierre Auger Observatory fluorescence detectors uses a light source at the telescope aperture. The technique accounts for the combined effects of all detector components in a single measurement. The calibrated 2.5 m diameter light source fills the aperture, providing uniform illumination to each pixel. The known flux from the light source and the response of the acquisition system give the required calibration for each pixel. In the lab, light source uniformity is studied using CCD images and the intensity is measured relative to NIST-calibrated photodiodes. Overall uncertainties are presently 12%, and are dominated by systematics. 13. Musical Activity Tunes Up Absolute Pitch Ability DEFF Research Database (Denmark) Dohn, Anders; Garza-Villarreal, Eduardo A.; Ribe, Lars Riisgaard; 2014-01-01 Absolute pitch (AP) is the ability to identify or produce pitches of musical tones without an external reference. Active AP (i.e., pitch production or pitch adjustment) and passive AP (i.e., pitch identification) are considered to not necessarily coincide, although no study has properly compared...... that APs generally undershoot when adjusting musical pitch, a tendency that decreases when musical activity increases. Finally, APs are less accurate when adjusting the pitch to black key targets than to white key targets. Hence, AP ability may be partly practice-dependent and we speculate that APs may...... benefit from frequent contact with fixed standard chroma to keep in tune.... 14. Absolute Priority for a Vehicle in VANET Science.gov (United States) Shirani, Rostam; Hendessi, Faramarz; Montazeri, Mohammad Ali; Sheikh Zefreh, Mohammad In today's world, traffic jams waste hundreds of hours of our life. This causes many researchers try to resolve the problem with the idea of Intelligent Transportation System. For some applications like a travelling ambulance, it is important to reduce delay even for a second. In this paper, we propose a completely infrastructure-less approach for finding shortest path and controlling traffic light to provide absolute priority for an emergency vehicle. We use the idea of vehicular ad-hoc networking to reduce the imposed travelling time. Then, we simulate our proposed protocol and compare it with a centrally controlled traffic light system. 15. Development of an absolute neutron dosimeter Energy Technology Data Exchange (ETDEWEB) Acevedo, C; Birstein, L; Loyola, H [Section de Desarrollos Innovativos, Comision Chilena de EnergIa Nuclear (CCHEN), Casilla 188-D, Santiago (Chile)], E-mail: lbirstei@cchen.cl 2008-11-01 An Absolute Neutron Dosimeter was developed to be used as a calibration standard for the Radiation Metrology Laboratory at CCHEN. The main component of the Dosimeter consists of a Proportional Counter of cylindrical shape, with Polyethylene walls and Ethylene gas in its interior. It includes a cage shaped arrangement of graphite bars that operates like the Proportional Counter cathode and a tungsten wire of 25 {mu}m in diameter {mu}m as the anode. Results of a Montecarlo modeling for the Dosimeter operation and results of tests and measurements performed with a radioactive source are presented. 16. ABSOLUT LOMO绝对创意 Institute of Scientific and Technical Information of China (English) 婷婷（整理） 2007-01-01 ABSOLUT与创意素来有着不解之缘。由Andy Warhal的ABSOLUT WARHOL至今，已有超过400位不同领域的创意大师为ABSOLUT的当代艺术宝库贡献了自己的得意之作。ABSOLUT的创意仿佛永远不会枯竭，而一系列的作品也让惊喜从未落空。 17. Processing Coordination Ambiguity Science.gov (United States) Engelhardt, Paul E.; Ferreira, Fernanda 2010-01-01 We examined temporarily ambiguous coordination structures such as "put the butter in the bowl and the pan on the towel." Minimal Attachment predicts that the ambiguous noun phrase "the pan" will be interpreted as a noun-phrase coordination structure because it is syntactically simpler than clausal coordination. Constraint-based theories assume… 18. Development and Validation of NODAL-LAMBDA Program for the Calculation of the Sub-criticality of LAMDA MODES By Nodal Methods in BWR reactors International Nuclear Information System (INIS) We have developed a 3D code with two energy groups and diffusion theory that is capable of calculating eigenvalues lambda of a BWR reactor using nodal methods and boundary conditions that calculates ALBEDO NODAL-LAMBDA from the properties of the reflector code itself. The code calculates the sub-criticality of the first harmonic, which is involved in the stability against oscillations reactor out of phase, and which is needed for calculating the decay rate for data out of phase oscillations. The code is very fast and in a few seconds is able to make a calculation of the first eigenvalues and eigenvectors, discretized solving the problem with different matrix elements zero. The code uses the LAPACK and ARPACK libraries. It was necessary to modify the LAPACK library to perform various operations with five non-diagonal matrices simultaneously in order to reduce the number of calls to bookstores and simplify the procedure for calculating the matrices in compressed format CSR. The code is validated by comparing it with the results for SIMULATE different cases and making 3D BENCHMAR of the IAEA. (Author) 19. Direct Load Control (DLC) Considering Nodal Interrupted Energy Assessment Rate (NIEAR) in Restructured Power Systems DEFF Research Database (Denmark) Wu, Qiuwei; Wang, Peng; Goel, Lalit 2010-01-01 A direct load control (DLC) scheme of air conditioning loads (ACL) considering direct monetary compensation to ACL customers for the service interruption caused by the DLC program is proposed in this paper for restructured power systems. The nodal interrupted energy assessment rate (NIEAR), which...... of the system energy cost, the system spinning reserve cost and the compensation cost to the ACL customers. Dynamic programming (DP) was used to obtain the optimal DLC scheme. The IEEE reliability test system (RTS) was studied to illustrate the proposed DLC scheme.......A direct load control (DLC) scheme of air conditioning loads (ACL) considering direct monetary compensation to ACL customers for the service interruption caused by the DLC program is proposed in this paper for restructured power systems. The nodal interrupted energy assessment rate (NIEAR), which... 20. Ablation of left-deviated dual atrioventricular nodal pathway from coronary sinus Institute of Scientific and Technical Information of China (English) HUANG Wei-bin; HONG Jiang; WANG Yan; ZHOU Fa-guang; ZENG Zhao-pin; GONG Yan; SUN Bao-gui; WANG Le-xin 2009-01-01 @@ Atrioventricular nodal reentrant tachycardia (AVNRT) is one of the most common types of paroxysmal supraventricular tachycardia. The mechanism of AVNRT is reentry associated with dual or multiple atrioventricular nodal (AVN) pathways. Typical AVNRT pathways,including fast and slow pathways, are confined in the right atrium. Radiofrequency catheter ablation of the slow pathway, and occasionally the fast pathway, has become the definitive treatment of choice for most symptomatic patients. Besides typical AVNRT, there exists some atypical AVNRT with various manifestations. Several groups have reported successful ablation of the leftward dual AVN pathway from the left side of the heart.1-3 We present one case of left-sided AVN as well as dual AVN pathway. The tachycardia was successfully eliminated by ablation of the slow pathway deep in the coronary sinus. 1. Traumatic Neuroma around the Celiac Trunk after Gastrectomy Mimicking a Nodal Metastasis: A Case Report Energy Technology Data Exchange (ETDEWEB) Kwon, Jung Hyeok; Ryu, Seung Wan; Kang, Yu Na [Keimyung University School of Medicine, Daegu (Korea, Republic of) 2007-06-15 Traumatic neuroma is a well-known disorder that occurs after trauma or surgery involving the peripheral nerve and develops from a nonneoplastic proliferation of the proximal end of a severed, partially transected, or injured nerve. However, in the abdomen, traumatic neuromas have been sporadically reported to occur in the bile duct. We present here a case of traumatic neuroma around the celiac trunk after gastrectomy that mimicks a nodal metastasis. In conclusion, the imaging finding of traumatic neuroma around the celiac trunk was a homogeneous hypovascular mass without narrowing or irregularity of encased arteries and without increased uptake on PET-CT. Although from a clinical standpoint, establishing an accurate preoperative diagnosis is difficult to perform, the presence of a traumatic neuroma should be included in the differential diagnosis of a mass around the celiac trunk in a patient that has undergone celiac nodal dissection. 2. STAR 3D nodal kinetics and thermal-hydraulic model for the Pennsylvania State TRIGA reactor International Nuclear Information System (INIS) A detailed three-dimensional (3D) time-dependent STAR nodal kinetics model coupled to a one-dimensional (1 D) thermal-hydraulics WIGL model has been developed to describe conservatively the peak power and pulse behavior of the Penn State University (PSU) Breazeale TRIGA reactor. This paper describes how the STAR model and its cross section data input was developed and benchmarked against actual TRIGA pulse experiments. Different core configurations (i.e., different core loading patterns, and with/without the TRIGA core next to the D20 tank) were used for several TRIGA pulse tests with different reactivity insertion worths (1.5$, 2.0$, 2.5$). This paper shows that the STAR nodal kinetics code adequately simulates TRIGA pulses when group constants are generated from physics codes (i.e., WIMS-D4) that can accurately model the TRIGA uranium-zirconium-hydride fuel. (author)
3. Variance computations for functional of absolute risk estimates
OpenAIRE
Pfeiffer, R. M.; E. Petracci
2011-01-01
We present a simple influence function based approach to compute the variances of estimates of absolute risk and functions of absolute risk. We apply this approach to criteria that assess the impact of changes in the risk factor distribution on absolute risk for an individual and at the population level. As an illustration we use an absolute risk prediction model for breast cancer that includes modifiable risk factors in addition to standard breast cancer risk factors. Influence function base...
4. Isotope dilution strategies for absolute quantitative proteomics
International Nuclear Information System (INIS)
The development of mass spectrometry (MS)-based methodologies for high-throughput protein identification has generated a concomitant need for protein quantification. Numerous MS-based relative quantification methodologies have been dedicated to the extensive comparison of multiple proteomes. On the other hand, absolute quantification methodologies, which allow the determination of protein concentrations in biological samples, are generally restricted to defined sets of proteins. Depending on the selected analytical procedure, absolute quantification approaches can provide accurate and precise estimations. These analytical performances are crucial for specific applications such as the evaluation of clinical bio-marker candidates. According to bioanalytical guidelines, accurate analytical processes require internal standards and quality controls. Regarding MS-based analysis of small molecules, isotope dilution has been recognized as the reference method for internal standardization. However, protein quantification methodologies which rely on the isotope dilution principle have been implemented in the proteomic field only recently. In these approaches, the sample is spiked with defined amounts of isotope-labeled analogue(s) of specific proteolytic peptide(s) (AQUA and QconCAT strategies) or protein(s) (PSAQ strategy). In this review, we present a critical overview of these isotope dilution methodologies. (authors)
5. A Maximum Likelihood Approach to Least Absolute Deviation Regression
Directory of Open Access Journals (Sweden)
Yinbo Li
2004-09-01
Full Text Available Least absolute deviation (LAD regression is an important tool used in numerous applications throughout science and engineering, mainly due to the intrinsic robust characteristics of LAD. In this paper, we show that the optimization needed to solve the LAD regression problem can be viewed as a sequence of maximum likelihood estimates (MLE of location. The derived algorithm reduces to an iterative procedure where a simple coordinate transformation is applied during each iteration to direct the optimization procedure along edge lines of the cost surface, followed by an MLE of location which is executed by a weighted median operation. Requiring weighted medians only, the new algorithm can be easily modularized for hardware implementation, as opposed to most of the other existing LAD methods which require complicated operations such as matrix entry manipulations. One exception is Wesolowsky's direct descent algorithm, which among the top algorithms is also based on weighted median operations. Simulation shows that the new algorithm is superior in speed to Wesolowsky's algorithm, which is simple in structure as well. The new algorithm provides a better tradeoff solution between convergence speed and implementation complexity.
6. Nodal collocation approximation for the multidimensional PL equations applied to transport source problems
Energy Technology Data Exchange (ETDEWEB)
Verdu, G. [Departamento de Ingenieria Quimica Y Nuclear, Universitat Politecnica de Valencia, Cami de Vera, 14, 46022. Valencia (Spain); Capilla, M.; Talavera, C. F.; Ginestar, D. [Dept. of Nuclear Engineering, Departamento de Matematica Aplicada, Universitat Politecnica de Valencia, Cami de Vera, 14, 46022. Valencia (Spain)
2012-07-01
PL equations are classical high order approximations to the transport equations which are based on the expansion of the angular dependence of the angular neutron flux and the nuclear cross sections in terms of spherical harmonics. A nodal collocation method is used to discretize the PL equations associated with a neutron source transport problem. The performance of the method is tested solving two 1D problems with analytical solution for the transport equation and a classical 2D problem. (authors)
7. In Vitro propagation of enterolobium cyclocarpum (guanacaste) from nodal explants of axenic seedlings
OpenAIRE
Araceli Rodríguez Sahagún; Osvaldo A. Castellanos Hernández; Gustavo J. Acevedo Hernández
2007-01-01
Enterolobium cyclocarpum (Jacq.) Griseb. is a multipurpose leguminous tree, considered an endangered species because of overexploitation and the slow rates of natural propagation due to the intrinsic characteristics of the tree. An alternative approach to overcome this problem is the establishment of systems for its rapid, mass propagation. In this work, a protocol for in vitro propagation of E. cyclocarpum using the axenic nodal segments obtained from in vitro germinated seedlings, was inves...
8. Acceleration of conduction velocity linked to clustering of nodal components precedes myelination
OpenAIRE
Freeman, Sean A.; Desmazières, Anne; Simonnet, Jean; Gatta, Marie; Pfeiffer, Friederike; Aigrot, Marie Stéphane; Rappeneau, Quentin; Guerreiro, Serge; Michel, Patrick Pierre; Yanagawa, Yuchio; Barbin, Gilles; Brophy, Peter. J.; Fricker, Desdemona; Lubetzki, Catherine; Sol-Foulon, Nathalie
2015-01-01
Cellular and molecular mechanisms underlying the assembly of nodes of Ranvier of myelinated axons in the CNS are still only partly understood. Our study shows the influence of intrinsic cues and glial extrinsic factors for nodal protein clustering before myelination on specific hippocampal neuronal subpopulations and extends to electrophysiological understandings and in vivo relevance. Although conduction velocity along axons has long been thought to mostly rely on the insulating properties o...
9. Traumatic Neuroma around the Celiac Trunk after Gastrectomy Mimicking a Nodal Metastasis: A Case Report
OpenAIRE
Kwon, Jung Hyeok; Ryu, Seung Wan; Kang, Yu Na
2007-01-01
Traumatic neuroma is a well-known disorder that occurs after trauma or surgery involving the peripheral nerve and develops from a nonneoplastic proliferation of the proximal end of a severed, partially transected, or injured nerve. We present a case of traumatic neuroma around the celiac trunk after gastrectomy in a 56-year-old man, which was confirmed by pathology. CT demonstrated the presence of a lobulated, homogeneous, hypoattenuating mass around the celiac trunk, mimicking a nodal metast...
10. A nodal method for solving the time-depending diffusion equation in the IQS approximation
International Nuclear Information System (INIS)
The fast and slow variation of the neutron flux shape needed for the dynamical description of nuclear reactor cores can be described advantageously in the Improved Quasistatic (IQS) model where the flux is factorized by a fast changing space-independent amplitude and a slow changing shape function. The basic equations of a time-dependent nodal approximation using the IQS method is presented.The calculational procedure of the response matrices is also described. (R.P.) 2 refs
11. EXTENSION OF THE 1D FOUR-GROUP ANALYTIC NODAL METHOD TO FULL MULTIGROUP
Energy Technology Data Exchange (ETDEWEB)
B. D. Ganapol; D. W. Nigg
2008-09-01
In the mid 80’s, a four-group/two-region, entirely analytical 1D nodal benchmark appeared. It was readily acknowledged that this special case was as far as one could go in terms of group number and still achieve an analytical solution. In this work, we show that by decomposing the solution to the multigroup diffusion equation into homogeneous and particular solutions, extension to any number of groups is a relatively straightforward exercise using the mathematics of linear algebra.
12. Numerical divergence effects of equivalence theory in the nodal expansion method
International Nuclear Information System (INIS)
Accurate solutions of the advanced nodal equations require the use of discontinuity factors (DFs) to account for the homogenization errors that are inherent in all coarse-mesh nodal methods. During the last several years, nodal equivalence theory (NET) has successfully been implemented for the Cartesian geometry and has received widespread acceptance in the light water reactor industry. The extension of NET to other reactor types has had limited success. Recent efforts to implement NET within the framework of the nodal expansion method have successfully been applied to the fast breeder reactor. However, attempts to apply the same methods to thermal reactors such as the Modular High-Temperature Gas Reactor (MHTGR) have led to numerical divergence problems that can be attributed directly to the magnitude of the DFs. In the work performed here, it was found that the numerical problems occur in the inner and upscatter iterations of the solution algorithm. These iterations use a Gauss-Seidel iterative technique that is always convergent for problems with unity DFs. However, for an MHTGR model that requires large DFs, both the inner and upscatter iterations were divergent. Initial investigations into methods for bounding the DFs have proven unsatisfactory as a means of remedying the convergence problems. Although the DFs could be bounded to yield a convergent solution, several cases were encountered where the resulting flux solution was less accurate than the solution without DFs. For the specific case of problems without upscattering, an alternate numerical method for the inner iteration, an LU decomposition, was identified and shown to be feasible
13. Two-energy group solution of the diffusion equation by the multidimensional nodal polynomial expansion method
International Nuclear Information System (INIS)
The EPON computer code based in a Nodal Polynomial Expansion Method, wrote in Fortran IV, for steady-state, square geometry, one-dimensional or two-dimensional geometry and for one or two-energy group is presented. The neutron and power flux distributions for nuclear power plants were calculated, comparing with codes that use similar or different methodologies. The availability, economy and speed of the methodology is demonstrated. (E.G.)
14. Global Structure of Nodal Solutions for Second-Order m-Point Boundary Value Problems with Superlinear Nonlinearities
OpenAIRE
An Yulian
2011-01-01
We consider the nonlinear eigenvalue problems , , , , where , and for with and satisfies for , and , where . We investigate the global structure of nodal solutions by using the Rabinowitz's global bifurcation theorem.
15. Is Rhythm Control with Pulmonary Vein Isolation Superior to Rate Control with AV Nodal Ablation in Patients with Heart Failure?
Directory of Open Access Journals (Sweden)
Dhanunjaya Lakkireddy MD, FACC
2008-12-01
Full Text Available Pulmonary-vein isolation is increasingly being used to treat atrial fibrillation in patients with heart failure. Is Pulmonary vein isolation better than AV nodal ablation with bi-ventricular pacing in patients with heart failure?
16. Nodal: master and commander of the dorsal-ventral and left-right axes in the sea urchin embryo.
Science.gov (United States)
Molina, M Dolores; de Crozé, Noémie; Haillot, Emmanuel; Lepage, Thierry
2013-08-01
Recent studies suggest that specification of the dorsal-ventral and left-right axes of the sea urchin embryo relies on Nodal-expressing signalling centres located in the ventral ectoderm and in the archenteron that share striking similarities with vertebrate organising centres. Nodal and its downstream target BMP2/4 pattern all three germ layers along the dorsal-ventral axis, repress neural fates and control morphogenesis of the larva. Moreover, Nodal establishes left-right asymmetry by repressing formation of the adult rudiment and inhibiting germline cells differentiation on the right side, while BMP2/4 promotes expression of mesodermal genes on the left side. These findings provide a framework for future studies and raise new questions regarding the events upstream and downstream of Nodal and BMP signalling during axis formation. PMID:23769944
17. A Conceptual Approach to Absolute Value Equations and Inequalities
Science.gov (United States)
Ellis, Mark W.; Bryson, Janet L.
2011-01-01
The absolute value learning objective in high school mathematics requires students to solve far more complex absolute value equations and inequalities. When absolute value problems become more complex, students often do not have sufficient conceptual understanding to make any sense of what is happening mathematically. The authors suggest that the…
18. Using, Seeing, Feeling, and Doing Absolute Value for Deeper Understanding
Science.gov (United States)
Ponce, Gregorio A.
2008-01-01
Using sticky notes and number lines, a hands-on activity is shared that anchors initial student thinking about absolute value. The initial point of reference should help students successfully evaluate numeric problems involving absolute value. They should also be able to solve absolute value equations and inequalities that are typically found in…
19. Invariant and Absolute Invariant Means of Double Sequences
Directory of Open Access Journals (Sweden)
Abdullah Alotaibi
2012-01-01
Full Text Available We examine some properties of the invariant mean, define the concepts of strong σ-convergence and absolute σ-convergence for double sequences, and determine the associated sublinear functionals. We also define the absolute invariant mean through which the space of absolutely σ-convergent double sequences is characterized.
20. Movement coordination during conversation.
Science.gov (United States)
Latif, Nida; Barbosa, Adriano V; Vatikiotis-Bateson, Eric; Vatiokiotis-Bateson, Eric; Castelhano, Monica S; Munhall, K G
2014-01-01
Behavioral coordination and synchrony contribute to a common biological mechanism that maintains communication, cooperation and bonding within many social species, such as primates and birds. Similarly, human language and social systems may also be attuned to coordination to facilitate communication and the formation of relationships. Gross similarities in movement patterns and convergence in the acoustic properties of speech have already been demonstrated between interacting individuals. In the present studies, we investigated how coordinated movements contribute to observers' perception of affiliation (friends vs. strangers) between two conversing individuals. We used novel computational methods to quantify motor coordination and demonstrated that individuals familiar with each other coordinated their movements more frequently. Observers used coordination to judge affiliation between conversing pairs but only when the perceptual stimuli were restricted to head and face regions. These results suggest that observed movement coordination in humans might contribute to perceptual decisions based on availability of information to perceivers. PMID:25119189
1. Movement coordination during conversation.
Directory of Open Access Journals (Sweden)
Nida Latif
Full Text Available Behavioral coordination and synchrony contribute to a common biological mechanism that maintains communication, cooperation and bonding within many social species, such as primates and birds. Similarly, human language and social systems may also be attuned to coordination to facilitate communication and the formation of relationships. Gross similarities in movement patterns and convergence in the acoustic properties of speech have already been demonstrated between interacting individuals. In the present studies, we investigated how coordinated movements contribute to observers' perception of affiliation (friends vs. strangers between two conversing individuals. We used novel computational methods to quantify motor coordination and demonstrated that individuals familiar with each other coordinated their movements more frequently. Observers used coordination to judge affiliation between conversing pairs but only when the perceptual stimuli were restricted to head and face regions. These results suggest that observed movement coordination in humans might contribute to perceptual decisions based on availability of information to perceivers.
2. Primary nodal peripheral T-cell lymphomas: diagnosis and therapeutic considerations
Directory of Open Access Journals (Sweden)
Luis Alberto de Pádua Covas Lage
2015-08-01
Full Text Available Nodal peripheral T-cell lymphomas are a rare group of neoplasms derived from post-thymic and activated T lymphocytes. A review of scientific articles listed in PubMed, Lilacs, and the Cochrane Library databases was performed using the term "peripheral T-cell lymphomas". According to the World Health Organization classification of hematopoietic tissue tumors, this group of neoplasms consists of peripheral T-cell lymphoma not otherwise specified (PTCL-NOS, angioimmunoblastic T-cell lymphoma (AITL, anaplastic large cell lymphoma-anaplastic lymphoma kinase positive (ALCL-ALK+, and a provisional entity called anaplastic large cell lymphoma-anaplastic lymphoma kinase negative (ALCL-ALK-. Because the treatment and prognoses of these neoplasms involve different principles, it is essential to distinguish each one by its clinical, immunophenotypic, genetic, and molecular features. Except for anaplastic large cell lymphoma-anaplastic lymphoma kinase positive, which has no adverse international prognostic index, the prognosis of nodal peripheral T-cell lymphomas is worse than that of aggressive B-cell lymphomas. Chemotherapy based on anthracyclines provides poor outcomes because these neoplasms frequently have multidrug-resistant phenotypes. Based on this, the current tendency is to use intensified cyclophosphamide, doxorubicin, vincristine, prednisolone (CHOP regimens with the addition of new drugs, and autologous hematopoietic stem cell transplantation. This paper describes the clinical features and diagnostic methods, and proposes a therapeutic algorithm for nodal peripheral T-cell lymphoma patients.
3. Probabilistic d.c. power flow computation with correlated nodal powers
Energy Technology Data Exchange (ETDEWEB)
Huhnerbein, B.; Panosyan, A. [Leibniz Univ. of Hanover, Hanover (Germany). Inst. of Electric Power Systems
2007-07-01
Power flow computation is a method commonly used to plan power systems. This paper presented an approach for probabilistic power flow computation with the convolution method. The method considers arbitrary shaped density functions and can handle correlated input variables which is essential for nodal powers. The power flow equation was linearized with respect to the voltage angles leading to a d.c. load flow equation. The density function of the line currents and the annual loss energy were then determined from the probabilistic power flow computation. This innovative approach to probabilistic load flow computation adequately reproduced the stochastic nature of network utilization. The method is particularly useful for distribution networks with a large share of wind power injection or other stochastic influences. This study showed that the small variations between correlated nodal powers should not be neglected. The enlarged frequencies of boundary states can be attributed to the concurrence of maximum nodal powers. It was concluded that the algorithm should be extended to an a.c. load flow model and tested for use on transmission networks. 13 refs., 2 tabs., 4 figs.
4. A coarse-mesh nodal method-diffusive-mesh finite difference method
Energy Technology Data Exchange (ETDEWEB)
Joo, H.; Nichols, W.R.
1994-05-01
Modern nodal methods have been successfully used for conventional light water reactor core analyses where the homogenized, node average cross sections (XSs) and the flux discontinuity factors (DFs) based on equivalence theory can reliably predict core behavior. For other types of cores and other geometries characterized by tightly-coupled, heterogeneous core configurations, the intranodal flux shapes obtained from a homogenized nodal problem may not accurately portray steep flux gradients near fuel assembly interfaces or various reactivity control elements. This may require extreme values of DFs (either very large, very small, or even negative) to achieve a desired solution accuracy. Extreme values of DFs, however, can disrupt the convergence of the iterative methods used to solve for the node average fluxes, and can lead to a difficulty in interpolating adjacent DF values. Several attempts to remedy the problem have been made, but nothing has been satisfactory. A new coarse-mesh nodal scheme called the Diffusive-Mesh Finite Difference (DMFD) technique, as contrasted with the coarse-mesh finite difference (CMFD) technique, has been developed to resolve this problem. This new technique and the development of a few-group, multidimensional kinetics computer program are described in this paper.
5. Anisotropic density fluctuations, plasmons, and Friedel oscillations in nodal line semimetal
Science.gov (United States)
Rhim, Jun-Won; Kim, Yong Baek
2016-04-01
Motivated by recent experimental efforts on three-dimensional semimetals, we investigate the static and dynamic density response of the nodal line semimetal by computing the polarizability for both undoped and doped cases. The nodal line semimetal in the absence of doping is characterized by a ring-shape zero energy contour in momentum space, which may be considered as a collection of Dirac points. In the doped case, the Fermi surface has a torus shape and two independent processes of the momentum transfer contribute to the singular features of the polarizability even though we only have a single Fermi surface. In the static limit, there exist two independent singularities in the second derivative of the static polarizability. This results in the highly anisotropic Friedel oscillations which show the angle-dependent algebraic power law and the beat phenomena in the oscillatory electron density near a charged impurity. Furthermore, the dynamical polarizability has two singular lines along {\\hslash }ω =γ p and {\\hslash }ω =γ p{sin}η , where η is the angle between the external momentum {p} and the plane where the nodal ring lies. From the dynamical polarizability, we obtain the plasmon modes in the doped case, which show anisotropic dispersions and angle-dependent plasma frequencies. Qualitative differences between the low and high doping regimes are discussed in light of future experiments.
6. Inhibition of lymphangiogenesis, nodal and lung metastasis by dihydroartemisinin in mice bearing Lewis lung carcinoma
Institute of Scientific and Technical Information of China (English)
2007-01-01
Objective: To investigate the activity of anti-malarial dihydroartemisinin (DHA) on tumor growth, lymphangiogenesis, nodal and lung metastasis and survival in mice bearing Lewis lung carcimoma (LLC). Methods: The models of C57BL/6 mice transplantation tumors were established via subcutaneous injection of LLC cells and divided into 4 groups: control group, DHA group, DHA + ferrous sulfate (FS) group and FS group, with 25 mice in each group. Tumor volumes and weights, nodal and lung metastasis, and survival were monitored. Tumor lymphatic microvessel density (LMVD) was determined by lymphatic vessel endothelial hyaluronan receptor-1 (LYVE-1) immnohistochemistry. After LLC cells were treated with DHA or DHA + FS, protein and mRNA levels of vascular endothelial growth factor (VEGF) -C were evaluated by Western blotting and real time quantitative RT-PCR, respectively. Results: Oral administration of DHA or DHA+FS inhibited lymph node and lung metastasis, and prolonged survival. However, no significant tumor growth retardation effect was observed when mice were treated with DHA alone. The inhibited tumor metastasis was related to the decreased LMVD in the peritumoral regions, but not in the in-tratumoral regions. DHA significantly down-regulated the expression of VEGF-C protein and mRNA in LLC cells. Conclusion; DHA effectively inhibits LLC transplantation tumor lymphangiogenesis, nodal and lung metastasis, and may be a promising chemotherapeutic agent for controlling lung cancer metastasis by decreasing VEGF-C expression.
7. Radiation therapy for early stage low grade non-Hodgkin's lymphoma of nodal presentation
International Nuclear Information System (INIS)
8. Symbolic Nodal Analysis of Analog Circuits with Modern Multiport Functional Blocks
Directory of Open Access Journals (Sweden)
C. Sanchez-Lopez
2013-06-01
Full Text Available This paper proposes admittance matrix models to approach the behavior of six modern multiport functional blocks called: differential difference amplifier, differential difference operational floating amplifier, differential difference operational mirror amplifier, differential difference current conveyor, current backward transconductance amplifier and current differencing transconductance amplifier. The novelty is that the behavior of any active device mentioned before can immediately be introduced in the nodal admittance matrix by using the proposed admittance matrix models and without requiring the use of extra variables. Therefore, a standard nodal analysis is applied to compute fully-symbolic small-signal performance parameters of analog circuits containing any active device mentioned above. This means that not only the size of the admittance matrix is smaller than those generated by applying modified nodal analysis method, for instance, but also, the number of nonzero elements and the generations of cancellation-terms are both reduced. An analysis example for each amplifier is provided in order to show the useful of the proposed stamps.
9. Some topics on safety analysis and accident nodalization of CAREM-25
International Nuclear Information System (INIS)
The main goal of nuclear safety area in the CAREM Project Phase I, carried out during 1999, was to consolidate the safety systems design through an integral analysis of the reactor and the safety systems response to different accidental sequences. A primary circuit nodalization, including the steam generators, was done with RELAP5 code. The modeling of System 230 (absorber rods drive feed water system), System 1400 (purification and control volume system) and steam condensation on the absorber rods drive system and on RPV wall is implemented through boundary conditions. Also the Residual Heat Removal System and the Second Shutdown system are modeled. The reactor steady state at full power was calculated. The results agree quite well with design values. It can be said from the accident analysis that the nodalization responds properly. Further analysis should be done in order to qualify the nodalization and to compare benchmarks with other codes and experimental data. On the other hand, the steam dome model should be improved with more precise data about absorber rods drive system condensation, loss of heat and inner components layout. (author)
10. A coarse-mesh nodal method-diffusive-mesh finite difference method
International Nuclear Information System (INIS)
Modern nodal methods have been successfully used for conventional light water reactor core analyses where the homogenized, node average cross sections (XSs) and the flux discontinuity factors (DFs) based on equivalence theory can reliably predict core behavior. For other types of cores and other geometries characterized by tightly-coupled, heterogeneous core configurations, the intranodal flux shapes obtained from a homogenized nodal problem may not accurately portray steep flux gradients near fuel assembly interfaces or various reactivity control elements. This may require extreme values of DFs (either very large, very small, or even negative) to achieve a desired solution accuracy. Extreme values of DFs, however, can disrupt the convergence of the iterative methods used to solve for the node average fluxes, and can lead to a difficulty in interpolating adjacent DF values. Several attempts to remedy the problem have been made, but nothing has been satisfactory. A new coarse-mesh nodal scheme called the Diffusive-Mesh Finite Difference (DMFD) technique, as contrasted with the coarse-mesh finite difference (CMFD) technique, has been developed to resolve this problem. This new technique and the development of a few-group, multidimensional kinetics computer program are described in this paper
11. Nodal Liquid Theory of the Pseudo-Gap Phase of High-Tc Superconductors
Science.gov (United States)
Balents, Leon; Fisher, Matthew P. A.; Nayak, Chetan
We introduce and study the nodal liquid, a novel zero-temperature quantum phase obtained by quantum-disordering a d-wave superconductor. It has numerous remarkable properties which lead us to suggest it as an explanation of the pseudo-gap state in underdoped high-temperature superconductors. In the absence of impurities, these include power-law magnetic order, a T-linear spin susceptibility, nontrivial thermal conductivity, and two- and one-particle charge gaps, the latter evidenced, e.g. in transport and electron photoemission (which exhibits pronounced fourfold anisotropy inherited from the d-wave quasiparticles). We use a (2+1)-dimensional duality transformation to derive an effective field theory for this phase. The theory is comprised of gapless neutral Dirac particles living at the former d-wave nodes, weakly coupled to the fluctuating gauge field of a dual Ginzburg-Landau theory. The nodal liquid interpolates naturally between the d-wave superconductor and the insulating antiferromagnet, and our effective field theory is powerful enough to permit a detailed analysis of a panoply of interesting phenomena, including charge ordering, antiferromagnetism, and d-wave superconductivity. We also discuss the zero-temperature quantum phase transitions which separate the nodal liquid from various ordered phases.
12. Planar cell polarity enables posterior localization of nodal cilia and left-right axis determination during mouse and Xenopus embryogenesis.
Directory of Open Access Journals (Sweden)
Dragana Antic
Full Text Available Left-right asymmetry in vertebrates is initiated in an early embryonic structure called the ventral node in human and mouse, and the gastrocoel roof plate (GRP in the frog. Within these structures, each epithelial cell bears a single motile cilium, and the concerted beating of these cilia produces a leftward fluid flow that is required to initiate left-right asymmetric gene expression. The leftward fluid flow is thought to result from the posterior tilt of the cilia, which protrude from near the posterior portion of each cell's apical surface. The cells, therefore, display a morphological planar polarization. Planar cell polarity (PCP is manifested as the coordinated, polarized orientation of cells within epithelial sheets, or as directional cell migration and intercalation during convergent extension. A set of evolutionarily conserved proteins regulates PCP. Here, we provide evidence that vertebrate PCP proteins regulate planar polarity in the mouse ventral node and in the Xenopus gastrocoel roof plate. Asymmetric anterior localization of VANGL1 and PRICKLE2 (PK2 in mouse ventral node cells indicates that these cells are planar polarized by a conserved molecular mechanism. A weakly penetrant Vangl1 mutant phenotype suggests that compromised Vangl1 function may be associated with left-right laterality defects. Stronger functional evidence comes from the Xenopus GRP, where we show that perturbation of VANGL2 protein function disrupts the posterior localization of motile cilia that is required for leftward fluid flow, and causes aberrant expression of the left side-specific gene Nodal. The observation of anterior-posterior PCP in the mouse and in Xenopus embryonic organizers reflects a strong evolutionary conservation of this mechanism that is important for body plan determination.
Science.gov (United States)
Chambers, J. E.
2003-08-01
A variety of coordinate systems have been used to study the N-body problem for cases involving a dominant central mass. These include the traditional Keplerian orbital elements and the canonical Delaunay variables, which both incorporate conserved quantities of the two-body problem. Recently, Cartesian coordinate systems have returned to favour with the rise of mixed-variable symplectic integrators, since these coordinates prove to be more efficient than using orbital elements. Three sets of canonical Cartesian coordinates are well known, each with its own advantages and disadvantages. Inertial coordinates (which include barycentric coordinates as a special case) are the simplest and easiest to implement. However, they suffer from the disadvantage that the motion of the central body must be calculated explicitly, leading to relatively large errors in general. Jacobi coordinates overcome this problem by replacing the coordinates and momenta of the central body with those of the system as a whole, so that momentum is conserved exactly. This leads to substantial improvements in accuracy, but has the disadvantage that every object is treated differently, and interactions between each pair of bodies are now expressed in a complicated manner involving the coordinates of many bodies. Canonical heliocentric coordinates (also known as democratic heliocentric coordinates) treat all bodies equally, and conserve the centre of mass motion, but at the cost of introducing momentum cross terms into the kinetic energy. This complicates the development of higher order symplectic integrators and symplectic correctors, as well as the development of methods used to resolve close encounters with the central body. Here I will re-examine the set of possible canonical Cartesian coordinate systems to determine if it is possible to (a) conserve the centre of mass motion, (b) treat all bodies equally, and (c) eliminate the momentum cross terms. I will demonstrate that this is indeed possible
14. Potential Pitfall in the Assessment of Lung Cancer with FDG-PET/CT: Talc Pleurodesis Causes Intrathoracic Nodal FDG Avidity
Directory of Open Access Journals (Sweden)
Yingbing Wang
2013-01-01
Full Text Available Objective. Talc pleurodesis is a common procedure performed to treat complications related to lung cancer. The purpose of our study was to characterize any thoracic nodal findings on FDG PET/CT associated with prior talc pleurodesis. Materials and Methods. The electronic medical record identified 44 patients who underwent PET/CT between January 2006 and December 2010 and had a history of talc pleurodesis. For each exam, we evaluated the distribution pattern, size, and attenuation of intrathoracic lymph nodes and the associated standardized uptake value. Results. High-attenuation intrathoracic lymph nodes were noted in 11 patients (25%, and all had corresponding increased FDG uptake (range 2–9 mm. Involved nodal groups were anterior peridiaphragmatic (100%, paracardiac (45%, internal mammary (25%, and peri-IVC (18% nodal stations. Seven of the 11 patients (63% had involvement of multiple lymph nodal groups. Mean longitudinal PET/CT and standalone CT followups of 15±11 months showed persistence of both high-attenuation and increased uptake at these sites, without increase in nodal size suggesting metastatic disease involvement. Conclusions. FDG avid, high-attenuation lymph nodes along the lymphatic drainage pathway for parietal pleura are a relatively common finding following talc pleurodesis and should not be mistaken for nodal metastases during the evaluation of patients with history of lung cancer.
15. Final Report, Nuclear Energy Research Initiative (NERI) Project: An Innovative Reactor Analysis Methodology Based on a Quasidiffusion Nodal Core Model
International Nuclear Information System (INIS)
OAK (B204) Final Report, NERI Project: ''An Innovative Reactor Analysis Methodology Based on a Quasidiffusion Nodal Core Model'' The present generation of reactor analysis methods uses few-group nodal diffusion approximations to calculate full-core eigenvalues and power distributions. The cross sections, diffusion coefficients, and discontinuity factors (collectively called ''group constants'') in the nodal diffusion equations are parameterized as functions of many variables, ranging from the obvious (temperature, boron concentration, etc.) to the more obscure (spectral index, moderator temperature history, etc.). These group constants, and their variations as functions of the many variables, are calculated by assembly-level transport codes. The current methodology has two main weaknesses that this project addressed. The first weakness is the diffusion approximation in the full-core calculation; this can be significantly inaccurate at interfaces between different assemblies. This project used the nodal diffusion framework to implement nodal quasidiffusion equations, which can capture transport effects to an arbitrary degree of accuracy. The second weakness is in the parameterization of the group constants; current models do not always perform well, especially at interfaces between unlike assemblies. The project developed a theoretical foundation for parameterization and homogenization models and used that theory to devise improved models. The new models were extended to tabulate information that the nodal quasidiffusion equations can use to capture transport effects in full-core calculations
16. The Use of System Codes in Scaling Studies: Relevant Techniques for Qualifying NPP Nodalizations for Particular Scenarios
Directory of Open Access Journals (Sweden)
V. Martinez-Quiroga
2014-01-01
Full Text Available System codes along with necessary nodalizations are valuable tools for thermal hydraulic safety analysis. Qualifying both codes and nodalizations is an essential step prior to their use in any significant study involving code calculations. Since most existing experimental data come from tests performed on the small scale, any qualification process must therefore address scale considerations. This paper describes the methodology developed at the Technical University of Catalonia in order to contribute to the qualification of Nuclear Power Plant nodalizations by means of scale disquisitions. The techniques that are presented include the so-called Kv-scaled calculation approach as well as the use of “hybrid nodalizations” and “scaled-up nodalizations.” These methods have revealed themselves to be very helpful in producing the required qualification and in promoting further improvements in nodalization. The paper explains both the concepts and the general guidelines of the method, while an accompanying paper will complete the presentation of the methodology as well as showing the results of the analysis of scaling discrepancies that appeared during the posttest simulations of PKL-LSTF counterpart tests performed on the PKL-III and ROSA-2 OECD/NEA Projects. Both articles together produce the complete description of the methodology that has been developed in the framework of the use of NPP nodalizations in the support to plant operation and control.
17. Use of Absolute and Comparative Performance Feedback in Absolute and Comparative Judgments and Decisions
Science.gov (United States)
Moore, Don A.; Klein, William M. P.
2008-01-01
Which matters more--beliefs about absolute ability or ability relative to others? This study set out to compare the effects of such beliefs on satisfaction with performance, self-evaluations, and bets on future performance. In Experiment 1, undergraduate participants were told they had answered 20% correct, 80% correct, or were not given their…
18. Variance computations for functional of absolute risk estimates.
Science.gov (United States)
Pfeiffer, R M; Petracci, E
2011-07-01
We present a simple influence function based approach to compute the variances of estimates of absolute risk and functions of absolute risk. We apply this approach to criteria that assess the impact of changes in the risk factor distribution on absolute risk for an individual and at the population level. As an illustration we use an absolute risk prediction model for breast cancer that includes modifiable risk factors in addition to standard breast cancer risk factors. Influence function based variance estimates for absolute risk and the criteria are compared to bootstrap variance estimates.
19. Analysis of the asymmetrically expressed Ablim1 locus reveals existence of a lateral plate Nodal-independent left sided signal and an early, left-right independent role for nodal flow
Directory of Open Access Journals (Sweden)
Hilton Helen
2010-05-01
Full Text Available Abstract Background Vertebrates show clear asymmetry in left-right (L-R patterning of their organs and associated vasculature. During mammalian development a cilia driven leftwards flow of liquid leads to the left-sided expression of Nodal, which in turn activates asymmetric expression of the transcription factor Pitx2. While Pitx2 asymmetry drives many aspects of asymmetric morphogenesis, it is clear from published data that additional asymmetrically expressed loci must exist. Results A L-R expression screen identified the cytoskeletally-associated gene, actin binding lim protein 1 (Ablim1, as asymmetrically expressed in both the node and left lateral plate mesoderm (LPM. LPM expression closely mirrors that of Nodal. Significantly, Ablim1 LPM asymmetry was detected in the absence of detectable Nodal. In the node, Ablim1 was initially expressed symmetrically across the entire structure, resolving to give a peri-nodal ring at the headfold stage in a flow and Pkd2-dependent manner. The peri-nodal ring of Ablim1 expression became asymmetric by the mid-headfold stage, showing stronger right than left-sided expression. Node asymmetry became more apparent as development proceeded; expression retreated in an anticlockwise direction, disappearing first from the left anterior node. Indeed, at early somite stages Ablim1 shows a unique asymmetric expression pattern, in the left lateral plate and to the right side of the node. Conclusion Left LPM Ablim1 is expressed in the absence of detectable LPM Nodal, clearly revealing existence of a Pitx2 and Nodal-independent left-sided signal in mammals. At the node, a previously unrecognised action of early nodal flow and Pkd2 activity, within the pit of the node, influences gene expression in a symmetric manner. Subsequent Ablim1 expression in the peri-nodal ring reveals a very early indication of L-R asymmetry. Ablim1 expression analysis at the node acts as an indicator of nodal flow. Together these results make
20. Absolute geostrophic currents in global tropical oceans
Science.gov (United States)
Yang, Lina; Yuan, Dongliang
2016-11-01
A set of absolute geostrophic current (AGC) data for the period January 2004 to December 2012 are calculated using the P-vector method based on monthly gridded Argo profiles in the world tropical oceans. The AGCs agree well with altimeter geostrophic currents, Ocean Surface Current Analysis-Real time currents, and moored current-meter measurements at 10-m depth, based on which the classical Sverdrup circulation theory is evaluated. Calculations have shown that errors of wind stress calculation, AGC transport, and depth ranges of vertical integration cannot explain non-Sverdrup transport, which is mainly in the subtropical western ocean basins and equatorial currents near the Equator in each ocean basin (except the North Indian Ocean, where the circulation is dominated by monsoons). The identified non-Sverdrup transport is thereby robust and attributed to the joint effect of baroclinicity and relief of the bottom (JEBAR) and mesoscale eddy nonlinearity.
1. Absolute measurements of fast neutrons using yttrium
International Nuclear Information System (INIS)
Yttrium is presented as an absolute neutron detector for pulsed neutron sources. It has high sensitivity for detecting fast neutrons. Yttrium has the property of generating a monoenergetic secondary radiation in the form of a 909 keV gamma-ray caused by inelastic neutron interaction. It was calibrated numerically using MCNPX and does not need periodic recalibration. The total yttrium efficiency for detecting 2.45 MeV neutrons was determined to be fn∼4.1x10-4 with an uncertainty of about 0.27%. The yttrium detector was employed in the NX2 plasma focus experiments and showed the neutron yield of the order of 108 neutrons per discharge.
2. Absolute astrometry in the next 50 years
CERN Document Server
Høg, Erik
2014-01-01
With ESA's astrometry satellite Gaia in orbit since December 2013 it is time to look at the future of fundamental astrometry and a time frame of 50 years is needed in this matter. A dozen science issues for a Gaia successor mission in twenty years are presented and in this context the possibilities for absolute astrometry with mas or sub-mas accuracies are discussed. The three powerful techniques: VLBI, the MICADO camera on the E-ELT, and the LSST are described and documented by literature references and by an extensive correspondence with leading astronomers who readily responded with all the information I needed. In brief, the two Gaia-like missions would provide an astrometric foundation for all branches of astronomy from the solar system and stellar systems to compact galaxies, quasars and dark matter by data which cannot be surpassed in the next 50 years.
3. How is an absolute democracy possible?
Directory of Open Access Journals (Sweden)
Joanna Bednarek
2011-01-01
Full Text Available In the last part of the Empire trilogy, Commonwealth, Negri and Hardt ask about the possibility of the self-governance of the multitude. When answering, they argue that absolute democracy, understood as the political articulation of the multitude that does not entail its unification (construction of the people is possible. As Negri states, this way of thinking about political articulation is rooted in the tradition of democratic materialism and constitutes the alternative to the dominant current of modern political philosophy that identifies political power with sovereignty. The multitude organizes itself politically by means of the constitutive power, identical with the ontological creativity or productivity of the multitude. To state the problem of political organization means to state the problem of class composition: political democracy is at the same time economic democracy.
4. Absolute radiometric calibration of the CCRS SAR
Science.gov (United States)
Ulander, Lars M. H.; Hawkins, Robert K.; Livingstone, Charles E.; Lukowski, Tom I.
1991-11-01
Determining the radar scattering coefficients from SAR (synthetic aperture radar) image data requires absolute radiometric calibration of the SAR system. The authors describe an internal calibration methodology for the airborne Canada Centre for Remote Sensing (CCRS) SAR system, based on radar theory, a detailed model of the radar system, and measurements of system parameters. The methodology is verified by analyzing external calibration data acquired over a 6-month period in 1988 by the C-band radar using HH polarization. The results indicate that the overall error is +/- 0.8 dB (1-sigma) for incidence angles +/- 20 deg from antenna boresight. The dominant error contributions are due to the antenna radome and uncertainties in the elevation angle relative to the antenna boresight.
5. WHY DOES LEIBNIZ NEED ABSOLUTE TIME?
Directory of Open Access Journals (Sweden)
NICOLÁS VAUGHAN C.
2007-08-01
Full Text Available Resumen: En este ensayo pongo en contraposición dos doctrinas conspicuamenteleibnicianas: la doctrina del tiempo relacional e ideal, y la doctrina de la armonía preestablecida. Argumentaré que si todas las substancias están necesariamentecoordinadas, entonces no tiene sentido negar el carácter absoluto y real del tiempo. En la primera sección describiré la concepción newtoniana y clarkeana del tiempo absoluto; en la segunda discutiré la crítica leibniciana a dicha concepción, crítica sobre la que se erige su doctrina relacional e ideal del tiempo; en la tercera sección daré un vistazo a la metafísica monádica madura de Leibniz, haciendo especial énfasis en la doctrina de la armonía preestablecida; finalmente, en la última sección sugeriré la existencia de una tensión irreconciliable entre estas dos doctrinas.Abstract: In this paper I bring together two characteristically Leibnizean doctrines:the doctrine of relational and ideal time, and the doctrine of preestablished harmony. I will argue that, if every substance is necessarily connected with another, then it makes no sense to deny absolute and real time. In the first section, I will describe Newton’s and Clarke’s conception of absolute time; then, in the second section, I will consider Leibniz’s critique of that conception, on which he bases his ideal and relational doctrine of time. In the third section I will look briefly at Leibniz’s mature monadic metaphysics, taking special account of his doctrine of preestablished harmony. In the last section, I will suggest that there is an irreconcilable tension between these two doctrines.
6. Extra-nodal lymphoma. A survey of Japan lymphoma radiation therapy group
Energy Technology Data Exchange (ETDEWEB)
Oguchi, Masahiko [Japanese Foundation for Cancer Research, Tokyo (Japan). Hospital; Ikeda, Hiroshi [National Cancer Center, Kashiwa, Chiba (Japan). East Hospital; Nakamura, Shigeo [Aichi Cancer Center, Nagoya (Japan). Hospital] [and others
2002-03-01
The purpose of this study was to examine, retrospectively, national-wide clinical data of patients with localized extranodal non-Hodgkin's lymphoma (NHL) who were treated by radiation therapy with or without chemotherapy. The survey was carried out at 25 radiation oncology institutions in Japan in 1998. In 1999, according to the Revised European American Lymphoma (REAL) classification, central pathological review conducted at Aichi cancer center was carried out for the data from 7 radiation oncology institutions. The 5-year progression free survival rates (PFS) were calculated to identify prognostic factors. Survey: Data from 1, 141 patients with stage I and II NHL were recruited from 1988 through 1992. Of them, 787 patients, who were treated using definitive radiotherapy with or without chemotherapy for intermediate and high-grade lymphomas in Working Formulation, constituted the core of this study. Primary tumors arose mainly from extra-nodal organs (71%) in the head and neck (Waldeyer's ring: 41%, thyroid gland: 7%, nasal cavities: 5%, oral cavities: 4%, sinus: 3%, orbital structures: 3%, skin: 2% and etc.). The median age of 60 years for patients with extra-nodal NHL was higher than that of 56 years for patients with nodal NHL (p<0.01). Female were dominant in incidence of extra-nodal NHL arising from the thyroid gland, skin and gastrointestinal tract. The percentage of stage I to the extra-nodal NHL from orbit, sino-nasal presentation was higher than that of other NHLs. The percentage of stage II to the extra-nodal NHL from Waldeyer's ring and thyroid gland was higher than that of other NHLs. Central pathological review was carried out for pathological data from 79 patients (Waldeyer's ring: 45, thyroid gland: 19, sinonasal cavities: 15). Of these, diffuse large B cell lymphoma (DLBCL) composed 63% of all patients, mucosa associated lyumphoid tissue lymphoma (MALT-L): 16%, Natural Killer/T cell lymphoma (NK/T-L): 11%, and mantle cell
7. Coordinating Interactions: The Event Coordination Notation
DEFF Research Database (Denmark)
Kindler, Ekkart
on a much more technical level. The Event Coordination Notation (ECNO) allows modelling the behaviour of an application on a high level of abstraction that is closer to the application’s domain than to the software realizing it. Still, these models contain all necessary details for actually executing....... The global behaviour of the application results from different elements jointly engaging in such events, which is called an interaction. Which events are supposed to be jointly executed and which elements need to join in is defined by so-called coordination diagrams of the ECNO. Together, the models...
8. Enhanced time overcurrent coordination
Energy Technology Data Exchange (ETDEWEB)
Enriquez, Arturo Conde; Martinez, Ernesto Vazquez [Universidad Autonoma de Nuevo Leon, Facultad de Ingenieria Mecanica y Electrica, Apdo. Postal 114-F, Ciudad Universitaria, CP 66450 San Nicolas de los Garza, Nuevo Leon (Mexico)
2006-04-15
In this paper, we recommend a new coordination system for time overcurrent relays. The purpose of the coordination process is to find a time element function that allows it to operate using a constant back-up time delay, for any fault current. In this article, we describe the implementation and coordination results of time overcurrent relays, fuses and reclosers. Experiments were carried out in a laboratory test situation using signals of a power electrical system physics simulator. (author)
9. Solution of the Boltzmann-Fokker-Planck transport equation using exponential nodal schemes; Solucion de la ecuacion de transporte de Boltzmann-Fokker-Planck usando esquemas nodales exponenciales
Energy Technology Data Exchange (ETDEWEB)
Ortega J, R.; Valle G, E. del [IPN-ESFM, 07738 Mexico D.F. (Mexico)]. e-mail: roj@correo.azc.uam.mx
2003-07-01
There are carried out charge and energy calculations deposited due to the interaction of electrons with a plate of a certain material, solving numerically the electron transport equation for the Boltzmann-Fokker-Planck approach of first order in plate geometry with a computer program denominated TEOD-NodExp (Transport of Electrons in Discreet Ordinates, Nodal Exponentials), using the proposed method by the Dr. J. E. Morel to carry out the discretization of the variable energy and several spatial discretization schemes, denominated exponentials nodal. It is used the Fokker-Planck equation since it represents an approach of the Boltzmann transport equation that is been worth whenever it is predominant the dispersion of small angles, that is to say, resulting dispersion in small dispersion angles and small losses of energy in the transport of charged particles. Such electrons could be those that they face with a braking plate in a device of thermonuclear fusion. In the present work its are considered electrons of 1 MeV that impact isotropically on an aluminum plate. They were considered three different thickness of plate that its were designated as problems 1, 2 and 3. In the calculations it was used the discrete ordinate method S{sub 4} with expansions of the dispersion cross sections until P{sub 3} order. They were considered 25 energy groups of uniform size between the minimum energy of 0.1 MeV and the maximum of 1.0 MeV; the one spatial intervals number it was considered variable and it was assigned the values of 10, 20 and 30. (Author)
10. Coordination failure caused by sunspots
DEFF Research Database (Denmark)
Beugnot, Julie; Gürgüç, Zeynep; Øvlisen, Frederik Roose;
2012-01-01
In a coordination game with Pareto-ranked equilibria, we study whether a sunspot can lead to either coordination on an inferior equilibrium (mis-coordination) or to out-of equilibrium behavior (dis-coordination). While much of the literature searches for mechanisms to attain coordination on the e......In a coordination game with Pareto-ranked equilibria, we study whether a sunspot can lead to either coordination on an inferior equilibrium (mis-coordination) or to out-of equilibrium behavior (dis-coordination). While much of the literature searches for mechanisms to attain coordination...
11. Social Postural Coordination
Science.gov (United States)
Varlet, Manuel; Marin, Ludovic; Lagarde, Julien; Bardy, Benoit G.
2011-01-01
The goal of the current study was to investigate whether a visual coupling between two people can produce spontaneous interpersonal postural coordination and change their intrapersonal postural coordination involved in the control of stance. We examined the front-to-back head displacements of participants and the angular motion of their hip and…
12. Coordinate measuring machines
DEFF Research Database (Denmark)
De Chiffre, Leonardo
This document is used in connection with three exercises of 2 hours duration as a part of the course GEOMETRICAL METROLOGY AND MACHINE TESTING. The exercises concern three aspects of coordinate measuring: 1) Measuring and verification of tolerances on coordinate measuring machines, 2) Traceability...
13. Gyrokinetic Statistical Absolute Equilibrium and Turbulence
Energy Technology Data Exchange (ETDEWEB)
Jian-Zhou Zhu and Gregory W. Hammett
2011-01-10
A paradigm based on the absolute equilibrium of Galerkin-truncated inviscid systems to aid in understanding turbulence [T.-D. Lee, "On some statistical properties of hydrodynamical and magnetohydrodynamical fields," Q. Appl. Math. 10, 69 (1952)] is taken to study gyrokinetic plasma turbulence: A finite set of Fourier modes of the collisionless gyrokinetic equations are kept and the statistical equilibria are calculated; possible implications for plasma turbulence in various situations are discussed. For the case of two spatial and one velocity dimension, in the calculation with discretization also of velocity v with N grid points (where N + 1 quantities are conserved, corresponding to an energy invariant and N entropy-related invariants), the negative temperature states, corresponding to the condensation of the generalized energy into the lowest modes, are found. This indicates a generic feature of inverse energy cascade. Comparisons are made with some classical results, such as those of Charney-Hasegawa-Mima in the cold-ion limit. There is a universal shape for statistical equilibrium of gyrokinetics in three spatial and two velocity dimensions with just one conserved quantity. Possible physical relevance to turbulence, such as ITG zonal flows, and to a critical balance hypothesis are also discussed.
14. Comparison between 18F-Fluorodeoxyglucose Positron Emission Tomography and Sentinel Lymph Node Biopsy for Regional Lymph Nodal Staging in Patients with Melanoma: A Review of the Literature
International Nuclear Information System (INIS)
Aim. to compare 18F-Fluorodeoxyglucose positron emission tomography (FDG-PET) to sentinel lymph node biopsy (SLNB) for regional lymph nodal staging in patients with melanoma. Methods. We performed a literature review discussing original articles which compared FDG-PET to SLNB for regional lymph nodal staging in patients with melanoma. Results and Conclusions. There is consensus in the literature that FDG-PET cannot replace SLNB for regional lymph nodal staging in patients with melanoma
15. Plant regeneration from single-nodal-stem explants of legume tree Prosopis alba Griseb.
Science.gov (United States)
Castillo de Meier, G; Bovo, O A
2000-08-01
Seeds of Prosopis alba were scarified with abrasive paper and placed to germinate on MS (Murashige and Skoog 1962) nutrient medium. After 7 days of culture, the basal part of cotyledons was removed and pieces of 4 mm" from distal parts were cultured on Murashige and Skoog (1962) mineral salts and vitamins (MS) (3% sucrose) supplemented with growth regulators. Callus proliferation took place in the majority of the media tested. A low percentage of calluses with green buds that developed on MS basal medium containing 0.1 mg.L-1 2,4-D alone or supplemented with BAP at 0.1 mg.L-1 was observed. Neither cotyledonary segments in any medium assayed regenerated the whole plants. Bud elongation (near 70%) was achieved when single-nodal-stem segments cut from 20 days old seedlings were cultured on MS salts supplemented with 3 mg.L-1 NAA or 3 mg.L-1 IBA combined with 0.05 mg.L-1 KIN after 60 days in culture. Multiple shoots per bud were also observed. Single-nodal-stem segments from five-year-old plants were also cultured on the same media used for seedling explants. Maximal frequency of explants with bud elongation (near 70%) was found on MS with 0.1 mg.L-1 NAA plus 1 mg.L-1 BAP after 60 days of culture. Single-nodal-stem explants cut from adult trees (more than 20 years) were also employed, but the number of bud elongation was lesser. For rooting, the elongated shoots were transferred to a semisolid or liquid MS culture medium employing a paper bridge, supplemented with 0.5 mg.L-1 IBA or 0.1 mg.L-1 NAA.
16. Acceleration of conduction velocity linked to clustering of nodal components precedes myelination.
Science.gov (United States)
Freeman, Sean A; Desmazières, Anne; Simonnet, Jean; Gatta, Marie; Pfeiffer, Friederike; Aigrot, Marie Stéphane; Rappeneau, Quentin; Guerreiro, Serge; Michel, Patrick Pierre; Yanagawa, Yuchio; Barbin, Gilles; Brophy, Peter J; Fricker, Desdemona; Lubetzki, Catherine; Sol-Foulon, Nathalie
2015-01-20
High-density accumulation of voltage-gated sodium (Nav) channels at nodes of Ranvier ensures rapid saltatory conduction along myelinated axons. To gain insight into mechanisms of node assembly in the CNS, we focused on early steps of nodal protein clustering. We show in hippocampal cultures that prenodes (i.e., clusters of Nav channels colocalizing with the scaffold protein ankyrinG and nodal cell adhesion molecules) are detected before myelin deposition along axons. These clusters can be induced on purified neurons by addition of oligodendroglial-secreted factor(s), whereas ankyrinG silencing prevents their formation. The Nav isoforms Nav1.1, Nav1.2, and Nav1.6 are detected at prenodes, with Nav1.6 progressively replacing Nav1.2 over time in hippocampal neurons cultured with oligodendrocytes and astrocytes. However, the oligodendrocyte-secreted factor(s) can induce the clustering of Nav1.1 and Nav1.2 but not of Nav1.6 on purified neurons. We observed that prenodes are restricted to GABAergic neurons, whereas clustering of nodal proteins only occurs concomitantly with myelin ensheathment on pyramidal neurons, implying separate mechanisms of assembly among different neuronal subpopulations. To address the functional significance of these early clusters, we used single-axon electrophysiological recordings in vitro and showed that prenode formation is sufficient to accelerate the speed of axonal conduction before myelination. Finally, we provide evidence that prenodal clusters are also detected in vivo before myelination, further strengthening their physiological relevance. PMID:25561543
17. Antibacterial activity of leaves and inter-nodal callus extracts of Mentha arvensis L
Institute of Scientific and Technical Information of China (English)
JohnsonM; WeselyEG; KavithaMS; UmaV
2011-01-01
Objective:To determine the anti-bacterial efficacy of chloroform, ethanol, ethyl acetate and water extracts of inter-nodal and leaves derived calli extracts from Mentha arvensis (M. arvensis) against Salmonella typhi(S. typhi), Streptococcus pyogenes(S. pyogenes), Proteus vulgaris(P. vulgaris) and Bacillus subtilis(B. subtilis). Methods: The inter-nodal and leaves segments of M. arvensis were cut into 0.5-0.7 cm in length and cultured on Murashige and Skoog solid medium supplemented with 3% sucrose, gelled with 0.7% agar and different concentration of 2, 4-Dichlorophenoxyacetie acid (2,4-D) either alone or in combinations. The preliminary phytochemical screening was performed by Brindha et al method. Antibacterial efficacy was performed by disc diffusion method and incubated for 24 h at 37 ℃. Results: Maximum percentage of callus formation (inter-nodal segments 84.3±0.78;leaves segments 93.8±1.27) was obtained on Murashige and Skoog’s basal medium supplemented with 3%sucrose and 1.5 mg/L of 2, 4-D. The ethanol extracts of leaves derived calli showed the maximum bio-efficacy than other solvents. The leaves and stem derived calli extracts on Proteus sp. showed that the plants can be used in the treatment of urinary tract infection associated with Proteus sp. Through the bacterial efficacy studies, it is confirmed that the in vitro raised calli tissue was more effective compared to in vivo tissue. Conclusions:The bio-efficacy study confirmed that the calli mediated tissues showed the maximum zone of inhibition. The present study paved a protocol to establish high potential cell lines by in vitro culture.
18. NodalB{copyright}: A unique program for optimum production of sucker rod pumping oil wells
Energy Technology Data Exchange (ETDEWEB)
Guirados, C.D.; Ercolino, J.M.; Sandoval, J.L. [and others
1995-12-31
Sucker rod pumping is the oldest artificial lift method used in production of oil wells. This method is usually designed and analyzed with the assistance of programs based on simplified models, such as the API RP 11L, or with a wave equation simulator. In many cases, however, a technique that permits consideration of the inflow and outflow performance of the well is a more efficient way to design and analyze an oil well. This technique, referred to as Total Analysis or System Analysis (SA), has been successfully applied to flowing and artificially lifted wells. This paper presents a computer program developed by Intevep S.A., called NodalB{copyright}, created to perform the SA of sucker rod pumping wells. NodalB{copyright}s unique characteristics make it a competitive program in todays market of design and optimization software. This program allows consideration of the inflow performance of the reservoir depending on the drilling scheme, either vertical or horizontal, and determination of the sensitivity of the rod pumping system to its most relevant parameters, such as: pumping speed and stroke, pump diameter, gas oil ratio, gas separation efficiency, tubing diameter, pump depth, rod string design, oil viscosity, injected diluent (diesel, kerosene, etc.) ratio, water cut, reservoir pressure, productivity index, and different production schemes (i.e. production through the tubing or through the casing-tubing annulus). These features show the power of this program as a predictive tool. NodalB{copyright} is specially applicable to design, optimization and troubleshooting of heavy and viscous oil wells, taking into account the viscosity effects in the rod pumping system.
19. Nodal quasi-particles of the high-Tc superconductors as carriers of heat
Directory of Open Access Journals (Sweden)
K. Behnia
2006-09-01
Full Text Available In the quest for understanding correlated electrons, high-temperature superconductivity remains a formidable challenge and a source of insight. This paper briefly recalls the central achievement by the study of heat transport at low temperatures. At very low temperatures, nodal quasi-particles of the d-wave superconducting gap become the main carriers of heat. Their thermal conductivity is unaffected by disorder and reflects the fine structure of the superconducting gap. This finding had led to new openings in the exploration of other unconventional superconductors
20. In vitro clonal propagation of Achyranthes aspera L. and Achyranthes bidentata Blume using nodal explants
Institute of Scientific and Technical Information of China (English)
Wesely Edward Gnanaraj; Johnson MarimuthuAntonisamy; Mohanamathi RB
2012-01-01
Objective: To develop the reproducible in vitro propagation protocols for the medicinally important plants viz., Achyranthes aspera (A. aspera) L. and Achyranthes bidentata (A. bidentata) Blume using nodal segments as explants. Methods: Young shoots of A. aspera and A. bidentata were harvested and washed with running tap water and treated with 0.1% bavistin and rinsed twice with distilled water. Then the explants were surface sterilized with 0.1% (w/v) HgCl2 solutions for 1 min. After rinsing with sterile distilled water for 3-4 times, nodal segments were cut into smaller segments (1 cm) and used as the explants. The explants were placed horizontally as well as vertically on solid basal Murashige and Skoog (MS) medium supplemented with 3% sucrose, 0.6% (w/v) agar (Hi-Media, Mumbai) and different concentration and combination of 6-benzyl amino purine (BAP), kinetin (Kin), naphthalene acetic acid (NAA) and indole acetic acid (IAA) for direct regeneration.Results:Adventitious proliferation was obtained from A. aspera and A. bidentata nodal segments inoculated on MS basal medium with 3% sucrose and augmented with BAP and Kin with varied frequency. MS medium augmented with 3.0 mg/L of BAP showed the highest percentage (93.60±0.71) of shootlets formation for A. aspera and (94.70±0.53) percentages for A. bidentata. Maximum number of shoots/explants (10.60±0.36) for A. aspera and (9.50±0.56) for A. bidentata was observed in MS medium fortified with 5.0 mg/L of BAP. For A. aspera, maximum mean length (5.50±0.34) of shootlets was obtained in MS medium augmented with 3.0 mg/L of Kin and for A. bidentata (5.40±0.61) was observed in the very same concentration. The highest percentage, maximum number of rootlets/shootlet and mean length of rootlets were observed in 1/2 MS medium supplemented with 1.0 mg/L of IBA. Seventy percentages of plants were successfully established in polycups. Sixty eight percentages of plants were well established in the green house condition
1. Nodal DG-FEM solution of high-order Boussinesq-type equations
DEFF Research Database (Denmark)
Engsig-Karup, Allan Peter; Hesthaven, Jan S.; Bingham, Harry B.;
2006-01-01
We present a discontinuous Galerkin finite element method (DG-FEM) solution to a set of high-order Boussinesq-type equations for modelling highly nonlinear and dispersive water waves in one and two horizontal dimensions. The continuous equations are discretized using nodal polynomial basis...... and convergence of the model with both h (grid size) and p (order) refinement are verified for the linearized equations, and calculations are provided for two nonlinear test cases in one horizontal dimension: harmonic generation over a submerged bar; and reflection of a steep solitary wave from a vertical wall...
2. SOLVABILITY OF FORWARD-BACKWARD SDES AND THE NODAL SET OF HAMILTON-JACOBI-BELLMAN EQUATIONS
Institute of Scientific and Technical Information of China (English)
MAJIN; YONGJIONGMIN
1995-01-01
The solvability of a class of forward-backward stochastic differential equations (SDEs for short) over an arbitrarily prescribed time duration is studied. The authors design a stochastic relaxed control problem, with both drift and difftusion all being controlled, so that the solvability problem is converted to a problem of finding the nodal set of the viscosity solution to a certain Hamilton-Jacobi-Bellman equation. This method overcomes the fatal difficulty encountered in the traditional contraction mapping approach to the existence theorem of such SDEs.
3. Stability and error analysis on modified nodal expansion method for transient convection-diffusion equation
International Nuclear Information System (INIS)
To further investigate the features of modified nodal expansion method (MNEM) for solving the convection-diffusion equation, the stability and error analysis were carried out. Based on sign preservation principle, the stability analysis reveals that the MNEM has inherent stability. The error analysis was implemented through a series of numerical experiments, and the results show that the MNEM is 3rd order scheme for one dimensional problem, while as 2nd order scheme for multidimensional problem because of using simple transverse leakage approximation. (authors)
4. Brill-Noether locus of rank 1 and degree g-1 on a nodal curve
CERN Document Server
Coelho, Juliana
2011-01-01
In this paper we consider the Brill-Noether locus $W_{\\underline d}(C)$ of line bundles of multidegree $\\underline d$ of total degree $g-1$ having a nonzero section on a nodal reducible curve $C$ of genus $g\\geq2$. We give an explicit description of the irreducible components of $W_{\\underline d}(C)$ for a semistable multidegre $\\underline d$. As a consequence we show that, if two semistable multidegrees of total degre $g-1$ on a curve with no rational components differ by a twister, then the respective Brill-Noether loci have isomorphic components.
5. Spectral Method with the Tensor-Product Nodal Basis for the Steklov Eigenvalue Problem
Directory of Open Access Journals (Sweden)
Xuqing Zhang
2013-01-01
Full Text Available This paper discusses spectral method with the tensor-product nodal basis at the Legendre-Gauss-Lobatto points for solving the Steklov eigenvalue problem. A priori error estimates of spectral method are discussed, and based on the work of Melenk and Wohlmuth (2001, a posterior error estimator of the residual type is given and analyzed. In addition, this paper combines the shifted-inverse iterative method and spectral method to establish an efficient scheme. Finally, numerical experiments with MATLAB program are reported.
6. Paroxysmal atrioventricular nodal reentrant tachycardias: epidemiology, clinical picture, diagnostics, treatment (review
Directory of Open Access Journals (Sweden)
Morozov I.A.
2012-03-01
Full Text Available Nowadays paroxysmal AV nodal reentrant tachycardia (AVNRT is one of the most widespread arrhythmias. In most cases AVRNT is a recurrent process, and it worsens the life quality of such patients, reduces their workability and increases the incidence of applying for medical help. Thus AVNRT today is of special attention among investigators. The interest of clinicians to the problem of cardiac arrhythmias is associated with permanent dissatisfaction with the results of antiarrhythmic therapy and also with the rapid development of the surgical methods of treatment, i.e. the use of radio frequency catheter ablation.
7. Light Spectral Quality Effects on the Growth of Potato (Solanum Tuberosum L.) Nodal Cutttings in Vitro
Science.gov (United States)
Wilson, Deborah A.; Weigel, Russell, C.; Wheeler, Raymond M.; Sager, John C.
1993-01-01
The effects of light spectral quality on the growth of in vitro nodal cutting of potato (Solanum tuberosum) cultivars Norland, Superior, Kennebec, and Denali were examined. The different light spectra were provided by Vita-Lite fluorescent (VF) (a white light control), blue fluorescent (BF), red fluorescent (RF), low-pressure sodium (LPS), and a combination of low-pressure sodium plus cool-white fluorescent lamp (LPS/CWF). Results suggested that shoot morphologic development of in vitro grown potato plants can be controlled by controlling irradiant spectral quality.
8. Absolute value preconditioning for symmetric indefinite linear systems
OpenAIRE
Vecharynski, Eugene; Knyazev, Andrew V.
2011-01-01
We introduce a novel strategy for constructing symmetric positive definite (SPD) preconditioners for linear systems with symmetric indefinite matrices. The strategy, called absolute value preconditioning, is motivated by the observation that the preconditioned minimal residual method with the inverse of the absolute value of the matrix as a preconditioner converges to the exact solution of the system in at most two steps. Neither the exact absolute value of the matrix nor its exact inverse ar...
9. Absolute nuclear material assay using count distribution (LAMBDA) space
Science.gov (United States)
Prasad, Manoj K.; Snyderman, Neal J.; Rowland, Mark S.
2012-06-05
A method of absolute nuclear material assay of an unknown source comprising counting neutrons from the unknown source and providing an absolute nuclear material assay utilizing a model to optimally compare to the measured count distributions. In one embodiment, the step of providing an absolute nuclear material assay comprises utilizing a random sampling of analytically computed fission chain distributions to generate a continuous time-evolving sequence of event-counts by spreading the fission chain distribution in time.
10. Absolute nuclear material assay using count distribution (LAMBDA) space
Science.gov (United States)
Prasad, Mano K.; Snyderman, Neal J.; Rowland, Mark S.
2015-12-01
A method of absolute nuclear material assay of an unknown source comprising counting neutrons from the unknown source and providing an absolute nuclear material assay utilizing a model to optimally compare to the measured count distributions. In one embodiment, the step of providing an absolute nuclear material assay comprises utilizing a random sampling of analytically computed fission chain distributions to generate a continuous time-evolving sequence of event-counts by spreading the fission chain distribution in time.
11. Nodal promotes the self-renewal of human colon cancer stem cells via an autocrine manner through Smad2/3 signaling pathway.
Science.gov (United States)
Gong, Yuehua; Guo, Ying; Hai, Yanan; Yang, Hao; Liu, Yang; Yang, Shi; Zhang, Zhenzhen; Ma, Meng; Liu, Linhong; Li, Zheng; He, Zuping
2014-01-01
Colorectal cancer is one of the most common and fatal tumors. However, molecular mechanisms underlying carcinogenesis of colorectal cancer remain largely undefined. Here, we explored the expression and function of Nodal in colon cancer stem cells (CCSCs). Nodal and its receptors were present in numerous human colorectal cancer cell lines. NODAL and ALK-4 were coexpressed in human colon cancerous tissues, and NODAL, CD24, and CD44, markers for CCSCs, were expressed at higher levels in human colon cancerous tissues than adjacent noncancerous colon tissues. Human CCSCs were isolated by magnetic activated cell sorting using anti-CD24 and anti-CD44. Nodal transcript and protein were hardly detectable in CD44- or CD24-negative human colorectal cancer cell lines, whereas Nodal and its receptors were present in CCSCs. Notably, Nodal facilitated spheroid formation of human CCSCs, and phosphorylation of Smad2 and Smad3 was activated by Nodal in cells of spheres derived from human CCSCs. Collectively, these results suggest that Nodal promotes the self-renewal of human CCSCs and mediate carcinogenesis of human colorectal cancer via an autocrine manner through Smad2/3 pathway. This study provides a novel insight into molecular mechanisms controlling fate of human CCSCs and offers new targets for gene therapy of human colorectal cancer.
12. The absolute disparity anomaly and the mechanism of relative disparities.
Science.gov (United States)
Chopin, Adrien; Levi, Dennis; Knill, David; Bavelier, Daphne
2016-06-01
There has been a long-standing debate about the mechanisms underlying the perception of stereoscopic depth and the computation of the relative disparities that it relies on. Relative disparities between visual objects could be computed in two ways: (a) using the difference in the object's absolute disparities (Hypothesis 1) or (b) using relative disparities based on the differences in the monocular separations between objects (Hypothesis 2). To differentiate between these hypotheses, we measured stereoscopic discrimination thresholds for lines with different absolute and relative disparities. Participants were asked to judge the depth of two lines presented at the same distance from the fixation plane (absolute disparity) or the depth between two lines presented at different distances (relative disparity). We used a single stimulus method involving a unique memory component for both conditions, and no extraneous references were available. We also measured vergence noise using Nonius lines. Stereo thresholds were substantially worse for absolute disparities than for relative disparities, and the difference could not be explained by vergence noise. We attribute this difference to an absence of conscious readout of absolute disparities, termed the absolute disparity anomaly. We further show that the pattern of correlations between vergence noise and absolute and relative disparity acuities can be explained jointly by the existence of the absolute disparity anomaly and by the assumption that relative disparity information is computed from absolute disparities (Hypothesis 1).
13. The Verification of Coupled Neutronics Thermal-Hydraulics Code NODAL3 in the PWR Rod Ejection Benchmark
Directory of Open Access Journals (Sweden)
Surian Pinem
2014-01-01
Full Text Available A coupled neutronics thermal-hydraulics code NODAL3 has been developed based on the few-group neutron diffusion equation in 3-dimensional geometry for typical PWR static and transient analyses. The spatial variables are treated by using a polynomial nodal method while for the neutron dynamic solver the adiabatic and improved quasistatic methods are adopted. In this paper we report the benchmark calculation results of the code against the OECD/NEA CRP PWR rod ejection cases. The objective of this work is to determine the accuracy of NODAL3 code in analysing the reactivity initiated accident due to the control rod ejection. The NEACRP PWR rod ejection cases are chosen since many organizations participated in the NEA project using various methods as well as approximations, so that, in addition to the reference solutions, the calculation results of NODAL3 code can also be compared to other codes’ results. The transient parameters to be verified are time of power peak, power peak, final power, final average Doppler temperature, maximum fuel temperature, and final coolant temperature. The results of NODAL3 code agree well with the PHANTHER reference solutions in 1993 and 1997 (revised. Comparison with other validated codes, DYN3D/R and ANCK, shows also a satisfactory agreement.
14. DIF3D nodal neutronics option for two- and three-dimensional diffusion theory calculations in hexagonal geometry
International Nuclear Information System (INIS)
A nodal method is developed for the solution of the neutron-diffusion equation in two- and three-dimensional hexagonal geometries. The nodal scheme has been incorporated as an option in the finite-difference diffusion-theory code DIF3D, and is intended for use in the analysis of current LMFBR designs. The nodal equations are derived using higher-order polynomial approximations to the spatial dependence of the flux within the hexagonal-z node. The final equations, which are cast in the form of inhomogeneous response-matrix equations for each energy group, involved spatial moments of the node-interior flux distribution plus surface-averaged partial currents across the faces of the node. These equations are solved using a conventional fission-source iteration accelerated by coarse-mesh rebalance and asymptotic source extrapolation. This report describes the mathematical development and numerical solution of the nodal equations, as well as the use of the nodal option and details concerning its programming structure. This latter information is intended to supplement the information provided in the separate documentation of the DIF3D code
15. Using star tracks to determine the absolute pointing of the Fluorescence Detector telescopes of the Pierre Auger Observatory
Energy Technology Data Exchange (ETDEWEB)
De Donato, Cinzia; Sanchez, Federico; /Milan U. /INFN, Milan; Santander, Marcos; Natl.Tech.U., San Rafael; Camin, Daniel; /Milan U. /INFN, Milan; Garcia, Beatriz; /Natl.; Grassi, Valerio; /Milan U. /INFN, Milan
2005-05-01
To accurately reconstruct a shower axis from the Fluorescence Detector data it is essential to establish with high precision the absolute pointing of the telescopes. To d that they calculate the absolute pointing of a telescope using sky background data acquired during regular data taking periods. The method is based on the knowledge of bright star's coordinates that provide a reliable and stable coordinate system. it can be used to check the absolute telescope's pointing and its long-term stability during the whole life of the project, estimated in 20 years. They have analyzed background data taken from January to October 2004 to determine the absolute pointing of the 12 telescopes installed both in Los Leones and Coihueco. The method is based on the determination of the mean-time of the variance signal left by a star traversing a PMT's photocathode which is compared with the mean-time obtained by simulating the track of that star on the same pixel.
16. Evaluation of the absolute regional temperature potential
Directory of Open Access Journals (Sweden)
D. T. Shindell
2012-09-01
Full Text Available The Absolute Regional Temperature Potential (ARTP is one of the few climate metrics that provides estimates of impacts at a sub-global scale. The ARTP presented here gives the time-dependent temperature response in four latitude bands (90–28° S, 28° S–28° N, 28–60° N and 60–90° N as a function of emissions based on the forcing in those bands caused by the emissions. It is based on a large set of simulations performed with a single atmosphere-ocean climate model to derive regional forcing/response relationships. Here I evaluate the robustness of those relationships using the forcing/response portion of the ARTP to estimate regional temperature responses to the historic aerosol forcing in three independent climate models. These ARTP results are in good accord with the actual responses in those models. Nearly all ARTP estimates fall within ±20% of the actual responses, though there are some exceptions for 90–28° S and the Arctic, and in the latter the ARTP may vary with forcing agent. However, for the tropics and the Northern Hemisphere mid-latitudes in particular, the ±20% range appears to be roughly consistent with the 95% confidence interval. Land areas within these two bands respond 39–45% and 9–39% more than the latitude band as a whole. The ARTP, presented here in a slightly revised form, thus appears to provide a relatively robust estimate for the responses of large-scale latitude bands and land areas within those bands to inhomogeneous radiative forcing and thus potentially to emissions as well. Hence this metric could allow rapid evaluation of the effects of emissions policies at a finer scale than global metrics without requiring use of a full climate model.
17. Absolute Radiometric Calibration of KOMPSAT-3A
Science.gov (United States)
Ahn, H. Y.; Shin, D. Y.; Kim, J. S.; Seo, D. C.; Choi, C. U.
2016-06-01
This paper presents a vicarious radiometric calibration of the Korea Multi-Purpose Satellite-3A (KOMPSAT-3A) performed by the Korea Aerospace Research Institute (KARI) and the Pukyong National University Remote Sensing Group (PKNU RSG) in 2015.The primary stages of this study are summarized as follows: (1) A field campaign to determine radiometric calibrated target fields was undertaken in Mongolia and South Korea. Surface reflectance data obtained in the campaign were input to a radiative transfer code that predicted at-sensor radiance. Through this process, equations and parameters were derived for the KOMPSAT-3A sensor to enable the conversion of calibrated DN to physical units, such as at-sensor radiance or TOA reflectance. (2) To validate the absolute calibration coefficients for the KOMPSAT-3A sensor, we performed a radiometric validation with a comparison of KOMPSAT-3A and Landsat-8 TOA reflectance using one of the six PICS (Libya 4). Correlations between top-of-atmosphere (TOA) radiances and the spectral band responses of the KOMPSAT-3A sensors at the Zuunmod, Mongolia and Goheung, South Korea sites were significant for multispectral bands. The average difference in TOA reflectance between KOMPSAT-3A and Landsat-8 image over the Libya 4, Libya site in the red-green-blue (RGB) region was under 3%, whereas in the NIR band, the TOA reflectance of KOMPSAT-3A was lower than the that of Landsat-8 due to the difference in the band passes of two sensors. The KOMPSAT-3Aensor includes a band pass near 940 nm that can be strongly absorbed by water vapor and therefore displayed low reflectance. Toovercome this, we need to undertake a detailed analysis using rescale methods, such as the spectral bandwidth adjustment factor.
18. Reduced radiation dose for elective nodal irradiation in node-negative anal cancer: back to the roots
Energy Technology Data Exchange (ETDEWEB)
Henkenberens, Christoph; Meinecke, Daniela; Bremer, Michael; Christiansen, Hans [Medizinische Hochschule Hannover, Hannover Medical School, Department of Radiation Oncology, Klinik fuer Strahlentherapie und Spezielle Onkologie, Hannover (Germany); Michael, Stoll [End- und Dickdarmzentrum Hannover, Hannover (Germany)
2015-11-15
19. Uranyl ion coordination
Science.gov (United States)
Evans, H.T.
1963-01-01
A review of the known crystal structures containing the uranyl ion shows that plane-pentagon coordination is equally as prevalent as plane-square or plane-hexagon. It is suggested that puckered-hexagon configurations of OH - or H2O about the uranyl group will tend to revert to plane-pentagon coordination. The concept of pentagonal coordination is invoked for possible explanations of the complex crystallography of the natural uranyl hydroxides and the unusual behavior of polynuclear ions in hydrolyzed uranyl solutions.
20. Indications for Pelvic Nodal Treatment in Prostate Cancer Should Change. Validation of the Roach Formula in a Large Extended Nodal Dissection Series
Energy Technology Data Exchange (ETDEWEB)
Abdollah, Firas [Department of Urology, Vita Salute San Raffaele University, Milan (Italy); Cozzarini, Cesare [Department of Radiation Therapy, Vita Salute San Raffaele University, Milan (Italy); Suardi, Nazareno; Gallina, Andrea; Capitanio, Umberto; Bianchi, Marco; Tutolo, Manuela; Salonia, Andrea [Department of Urology, Vita Salute San Raffaele University, Milan (Italy); La Macchia, Mariangela; Di Muzio, Nadia [Department of Radiation Therapy, Vita Salute San Raffaele University, Milan (Italy); Rigatti, Patrizio; Montorsi, Francesco [Department of Urology, Vita Salute San Raffaele University, Milan (Italy); Briganti, Alberto, E-mail: briganti.alberto@hsr.it [Department of Urology, Vita Salute San Raffaele University, Milan (Italy)
2012-06-01
Purpose: Previous studies have criticized the predicting ability of the Roach formula in assessing the risk of lymph node invasion (LNI) in contemporary patients with prostate cancer (PCa) due to a significant overestimation of LNI rates. However, all those studies included patients treated with limited pelvic lymph node dissection (PLND), which is associated with high rates of false negative findings. We hypothesized that the Roach formula is still an accurate tool for LNI predictions if an extended PLND (ePLND) is performed. Methods and Materials: We included 3,115 consecutive patients treated with radical prostatectomy and ePLND between 2000 and 2010 at a single tertiary referral center. Extended PLND consisted of removal of obturator, external iliac, and hypogastric lymph nodes. We externally validated the Roach formula by using the area under the receiver operating characteristics curve and calibration plot method. Moreover, we tested the performance characteristics of different formula-generated cutoff values ranging from 1% to 20%. Results: The accuracy of the Roach formula was 80.3%. The calibration showed only a minor underestimation of the LNI risk in high-risk patients (6.7%). According to the Roach formula, the use of 15% cut off would have allowed 74.2% (2,311/3,115) of patients to avoid nodal irradiation, while up to 32.7% (111/336) of all patients with LNI would have been missed. When the cut off was lowered to 6%, nodal treatment would have been spared in 1,541 (49.5%) patients while missing 41 LNI patients. The sensitivity, specificity, and negative predictive values associated with the 6% cut off were 87.9%, 54%, and 97.3%, respectively. Conclusions: The Roach formula is still accurate and does not overestimate the rate of LNI in contemporary prostate cancer patients if they are treated with ePLND. However, the recommended cut off of 15% would miss approximately one-third of patients with LNI. Based on our results, the cut off should be lowered to
1. Indications for Pelvic Nodal Treatment in Prostate Cancer Should Change. Validation of the Roach Formula in a Large Extended Nodal Dissection Series
International Nuclear Information System (INIS)
Purpose: Previous studies have criticized the predicting ability of the Roach formula in assessing the risk of lymph node invasion (LNI) in contemporary patients with prostate cancer (PCa) due to a significant overestimation of LNI rates. However, all those studies included patients treated with limited pelvic lymph node dissection (PLND), which is associated with high rates of false negative findings. We hypothesized that the Roach formula is still an accurate tool for LNI predictions if an extended PLND (ePLND) is performed. Methods and Materials: We included 3,115 consecutive patients treated with radical prostatectomy and ePLND between 2000 and 2010 at a single tertiary referral center. Extended PLND consisted of removal of obturator, external iliac, and hypogastric lymph nodes. We externally validated the Roach formula by using the area under the receiver operating characteristics curve and calibration plot method. Moreover, we tested the performance characteristics of different formula-generated cutoff values ranging from 1% to 20%. Results: The accuracy of the Roach formula was 80.3%. The calibration showed only a minor underestimation of the LNI risk in high-risk patients (6.7%). According to the Roach formula, the use of 15% cut off would have allowed 74.2% (2,311/3,115) of patients to avoid nodal irradiation, while up to 32.7% (111/336) of all patients with LNI would have been missed. When the cut off was lowered to 6%, nodal treatment would have been spared in 1,541 (49.5%) patients while missing 41 LNI patients. The sensitivity, specificity, and negative predictive values associated with the 6% cut off were 87.9%, 54%, and 97.3%, respectively. Conclusions: The Roach formula is still accurate and does not overestimate the rate of LNI in contemporary prostate cancer patients if they are treated with ePLND. However, the recommended cut off of 15% would miss approximately one-third of patients with LNI. Based on our results, the cut off should be lowered to
2. Coordinative alignment of molecules in chiral metal-organic frameworks.
Science.gov (United States)
Lee, Seungkyu; Kapustin, Eugene A; Yaghi, Omar M
2016-08-19
A chiral metal-organic framework, MOF-520, was used to coordinatively bind and align molecules of varying size, complexity, and functionality. The reduced motional degrees of freedom obtained with this coordinative alignment method allowed the structures of molecules to be determined by single-crystal x-ray diffraction techniques. The chirality of the MOF backbone also served as a reference in the structure solution for an unambiguous assignment of the absolute configuration of bound molecules. Sixteen molecules representing four common functional groups (primary alcohol, phenol, vicinal diol, and carboxylic acid), ranging in complexity from methanol to plant hormones (gibberellins, containing eight stereocenters), were crystallized and had their precise structure determined. We distinguished single and double bonds in gibberellins, and we enantioselectively crystallized racemic jasmonic acid, whose absolute configuration had only been inferred from derivatives. PMID:27540171
3. Inland waterway ports nodal attraction indices relevant in development strategies on regional level
Science.gov (United States)
Dinu, O.; Burciu, Ş.; Oprea, C.; Ilie, A.; Rosca, M.
2016-08-01
Present paper aims to propose a set of ranking indices and related criteria, concerning mainly spatial analysis, for the inland waterway port, with special view on inland ports of Danube. Commonly, the attraction potential of a certain transport node is assessed by its spatial accessibility indices considering both spatial features of the location provided by the networks that connect into that node and its economic potential defining the level of traffic flows depending on the economic centers of its hinterland. Paper starts with a overview of the critical needs that are required for potential sites to become inland waterway ports and presents nodal functions that coexist at different levels, leading to a port hierarchy from the points of view of: capacity, connection to hinterland, traffic structure and volume. After a brief review of the key inland waterway port ranking criterion, a selection of nodal attraction measures is made. Particular considerations for the Danube inland port case follows proposed methodology concerning indices of performance for network scale and centrality. As expected, the shorter the distance from an inland port to the nearest access point the greater accessibility. Major differences in ranking, dependent on selected criterion, were registered.
4. [Successful selective electrical ablation of the retrograde pathway in atrioventricular nodal reentry tachycardia associated with syncope].
Science.gov (United States)
Lukl, J; Cíhalík, C
1992-01-01
A 55-year-old man was admitted to the intensive care unit on account of repeatedly occurring syncopes which developed at the peak of physical exertion. The attack was reproduced by exercise on a bicycle ergometer: the patient developed paroxysmal tachycardia with a narrow QRS and a frequency of 160/min leading after 20 sec. to severe hypotension and loss of consciousness. The same tachycardia caused by programmed atrial stimulation caused a drop of tension in the recumbent position by 30 mmHg and after more detailed analysis during electrophysiological examination it was evaluated as atrioventricular nodal reentrant tachycardia. By an electric discharge of 300 J administered by means of a stimulation electrode 7F USCI into the area of the AV node the retrograde conduction through the perinodal rapid pathways was completely interrupted and 1st. degree atrioventricular block developed. Repeated electrophysiological examination and exercise tests on a bicycle ergometer provided evidence of the disappearance of the retrograde pathway and the impossibility to elicit AVNRT. The authors express the view that the rapid perinodal pathway is interrupted in successful cases in both directions and the 1st. degree AV block is due to conduction along a slow pathway and not incidental slowing of conduction along the rapid pathway which is the generally accepted interpretation. Modification of the atrioventricular conduction by interruption of the rapid pathway by fulguration is according to data in the literature and the described patient a method which makes is possible to cure severe atrioventricular nodal reentrant tachycardias.
5. An otx/nodal regulatory signature for posterior neural development in ascidians.
Directory of Open Access Journals (Sweden)
Agnès Roure
2014-08-01
Full Text Available In chordates, neural induction is the first step of a complex developmental process through which ectodermal cells acquire a neural identity. In ascidians, FGF-mediated neural induction occurs at the 32-cell stage in two blastomere pairs, precursors respectively of anterior and posterior neural tissue. We combined molecular embryology and cis-regulatory analysis to unveil in the ascidian Ciona intestinalis the remarkably simple proximal genetic network that controls posterior neural fate acquisition downstream of FGF. We report that the combined action of two direct FGF targets, the TGFβ factor Nodal, acting via Smad- and Fox-binding sites, and the transcription factor Otx suffices to trigger ascidian posterior neural tissue formation. Moreover, we found that this strategy is conserved in the distantly related ascidian Phallusia mammillata, in spite of extreme sequence divergence in the cis-regulatory sequences involved. Our results thus highlight that the modes of gene regulatory network evolution differ with the evolutionary scale considered. Within ascidians, developmental regulatory networks are remarkably robust to genome sequence divergence. Between ascidians and vertebrates, major fate determinants, such as Otx and Nodal, can be co-opted into different networks. Comparative developmental studies in ascidians with divergent genomes will thus uncover shared ascidian strategies, and contribute to a better understanding of the diversity of developmental strategies within chordates.
6. Synchronous Gastric Carcinoma and Nodal Malignant Lymphoma: A Rare Case Report and Literature Review
Directory of Open Access Journals (Sweden)
Li-Jun Xue
2010-07-01
Full Text Available Synchronous double malignancies of gastric carcinoma (GC and malignant lymphoma (ML are rare and very difficult to treat. We report a case of synchronous GC and nodal ML, regarding which clinical and pathological features and treatment are discussed. A 68-year-old woman with a history of inguinal hernia was admitted for abdominal pain and high fever and subsequently underwent herniorrhaphy, but the fever remained. Computerized tomography showed a stomach mass and multiple enlarged lymph nodes in the abdominal cavity and inguinal regions. Gastric adenocarcinoma coexistent with advanced in situ follicular lymphoma was confirmed by endoscopy, biopsy of inguinal lymph nodes and bone marrow examination. Two chemotherapy regimens, R-CHOP (rituximab, cyclophosphamide, perarubicin, vincristine and prednisone and systemic therapy (5-fluorouracil and calcium folinate combined with regional perfusion (oxaliplatin and etoposide through the left gastric artery were performed at intervals against ML and GC, respectively. Partial remission in both tumors was achieved after 4 courses of treatment, but the patient finally died of heart failure. Scrupulous biopsy of non-draining lymph nodes in patients with gastrointestinal carcinomas is supposed to improve the diagnostic rate of simultaneous nodal ML. The interval chemotherapy strategy with two independent regimens is beneficial for such patients, especially for those unable to tolerate major surgery.
7. Development of a New core/reflector model for coarse-mesh nodal methods
Energy Technology Data Exchange (ETDEWEB)
Pogosbekyan, Leonid; Cho, Jin Young; Kim, Young Il; Kim, Young Jin; Joo, Hyung Kuk; Chang, Moon Hee
1997-10-01
This work presents two approaches for reflector simulation in coarse-mesh nodal methods. The first approach is called Interface Matrix Technique (IMT), which simulates the baffle as a banishingly thin layer having the property of reflection and transmission. We applied this technique within the frame of AFEN (Analytic Function Expansion Nodal) method, and developed the AFEN-IM (Interface Matrix) method. AFEN-IM method shows 1.24% and 0.42 % in maximum and RMS (Root Mean Square) assemblywise power error for ZION-1 benchmark problem. The second approach is L-shaped reflector homogenization method. This method is based on the integral response conservation along the L-shaped core-reflector interface. The reference reflector response is calculated from 2-dimensional spectral calculation and the response of the homogenized reflector is derived from the one-node 2-dimensional AFEN problem solution. This method shows 5 times better accuracy than the 1-dimensional homogenization technique in the assemblywise power. Also, the concept of shroud/reflector homogenization for hexagonal core have been developed. The 1-dimensional spectral calculation was used for the determination of 2 group cross sections. The essence of homogenization concept consists in the calculation of equivalent shroud width, which preserve albedo for the fast neutrons in 2-dimensional reflector. This method shows a relative error less than 0.42% in assemblywise power and a difference of 9x10{sup -5} in multiplication factor for full-core model. (author). 9 refs., 3 tabs., 28 figs.
8. [Successful selective electrical ablation of the retrograde pathway in atrioventricular nodal reentry tachycardia associated with syncope].
Science.gov (United States)
Lukl, J; Cíhalík, C
1992-01-01
A 55-year-old man was admitted to the intensive care unit on account of repeatedly occurring syncopes which developed at the peak of physical exertion. The attack was reproduced by exercise on a bicycle ergometer: the patient developed paroxysmal tachycardia with a narrow QRS and a frequency of 160/min leading after 20 sec. to severe hypotension and loss of consciousness. The same tachycardia caused by programmed atrial stimulation caused a drop of tension in the recumbent position by 30 mmHg and after more detailed analysis during electrophysiological examination it was evaluated as atrioventricular nodal reentrant tachycardia. By an electric discharge of 300 J administered by means of a stimulation electrode 7F USCI into the area of the AV node the retrograde conduction through the perinodal rapid pathways was completely interrupted and 1st. degree atrioventricular block developed. Repeated electrophysiological examination and exercise tests on a bicycle ergometer provided evidence of the disappearance of the retrograde pathway and the impossibility to elicit AVNRT. The authors express the view that the rapid perinodal pathway is interrupted in successful cases in both directions and the 1st. degree AV block is due to conduction along a slow pathway and not incidental slowing of conduction along the rapid pathway which is the generally accepted interpretation. Modification of the atrioventricular conduction by interruption of the rapid pathway by fulguration is according to data in the literature and the described patient a method which makes is possible to cure severe atrioventricular nodal reentrant tachycardias. PMID:1561778
9. NODAL3 Sensitivity Analysis for NEACRP 3D LWR Core Transient Benchmark (PWR
Directory of Open Access Journals (Sweden)
Surian Pinem
2016-01-01
Full Text Available This paper reports the results of sensitivity analysis of the multidimension, multigroup neutron diffusion NODAL3 code for the NEACRP 3D LWR core transient benchmarks (PWR. The code input parameters covered in the sensitivity analysis are the radial and axial node sizes (the number of radial node per fuel assembly and the number of axial layers, heat conduction node size in the fuel pellet and cladding, and the maximum time step. The output parameters considered in this analysis followed the above-mentioned core transient benchmarks, that is, power peak, time of power peak, power, averaged Doppler temperature, maximum fuel centerline temperature, and coolant outlet temperature at the end of simulation (5 s. The sensitivity analysis results showed that the radial node size and maximum time step give a significant effect on the transient parameters, especially the time of power peak, for the HZP and HFP conditions. The number of ring divisions for fuel pellet and cladding gives negligible effect on the transient solutions. For productive work of the PWR transient analysis, based on the present sensitivity analysis results, we recommend NODAL3 users to use 2×2 radial nodes per assembly, 1×18 axial layers per assembly, the maximum time step of 10 ms, and 9 and 1 ring divisions for fuel pellet and cladding, respectively.
10. Nodal mantle cell lymphoma: A descriptive study from a tertiary care center in South India
Directory of Open Access Journals (Sweden)
Arun Roy
2013-01-01
Full Text Available Introduction: Mantle cell lymphoma (MCL is a type of B-cell non-Hodgkin lymphoma (NHL with distinctive morphologic, immunophenotypic and a characteristic cytogenetic abnormality, the t(11;14(q13;q32 and overexpression of cyclin D1. The common histologic features include effaced lymphoid architecture by a monomorphic lymphoid population with a vaguely nodular, diffuse or mantle zone growth pattern. The classic cytomorphologic features include small to medium sized lymphoid cells with irregular nuclear contours and scanty cytoplasm, closely resembling centrocytes. Materials and Methods: This retrospective study comprises 13 cases of MCL over a period of 5½ years in our department, comprising 4% of all nodal NHL diagnosed. All cases were diagnosed on lymph node biopsy. Results: The mean age of the presentation was 57 years. There was a male preponderance (M:F = 2.25:1. The disease was nodal in all cases. Most patients (84.5% had generalized lymphadenopathy and/or hepatosplenomegaly. Bone marrow involvement was seen in 81.8% of cases. Three cases showed a nodular pattern on lymph node biopsy while remaining ten had a diffuse pattern. Immunophenotyping showed positivity for CD20, CD5 and cyclin D1 and CD23 negativity. Conclusion: Despite certain morphological similarity to other low-grade/intermediate-grade lymphomas, MCL has a characteristic appearance of its own. Since it is more aggressive than other low-grade lymphomas it needs to be accurately diagnosed.
11. Advanced computational methods for nodal diffusion, Monte Carlo, and S(sub N) problems
Science.gov (United States)
Martin, W. R.
1993-01-01
This document describes progress on five efforts for improving effectiveness of computational methods for particle diffusion and transport problems in nuclear engineering: (1) Multigrid methods for obtaining rapidly converging solutions of nodal diffusion problems. An alternative line relaxation scheme is being implemented into a nodal diffusion code. Simplified P2 has been implemented into this code. (2) Local Exponential Transform method for variance reduction in Monte Carlo neutron transport calculations. This work yielded predictions for both 1-D and 2-D x-y geometry better than conventional Monte Carlo with splitting and Russian Roulette. (3) Asymptotic Diffusion Synthetic Acceleration methods for obtaining accurate, rapidly converging solutions of multidimensional SN problems. New transport differencing schemes have been obtained that allow solution by the conjugate gradient method, and the convergence of this approach is rapid. (4) Quasidiffusion (QD) methods for obtaining accurate, rapidly converging solutions of multidimensional SN Problems on irregular spatial grids. A symmetrized QD method has been developed in a form that results in a system of two self-adjoint equations that are readily discretized and efficiently solved. (5) Response history method for speeding up the Monte Carlo calculation of electron transport problems. This method was implemented into the MCNP Monte Carlo code. In addition, we have developed and implemented a parallel time-dependent Monte Carlo code on two massively parallel processors.
12. Spin-orbit interaction driven collective electron-hole excitations in a noncentrosymmetric nodal loop Weyl semimetal
Science.gov (United States)
Ahn, Kyo-Hoon; Lee, Kwan-Woo; Pickett, Warren E.
2015-09-01
NbP is one member of a new class of nodal loop semimetals characterized by the cooperative effects of spin-orbit coupling (SOC) and a lack of inversion center. Here transport and spectroscopic properties of NbP are evaluated using density functional theory methods. SOC together with the lack of inversion symmetry splits degeneracies, giving rise to "Russian doll nested" Fermi surfaces containing 4 ×10-4 electron (hole) carriers/f.u. Due to the modest SOC strength in Nb, the Fermi surfaces map out the Weyl nodal loops. Calculated structure around T*≈100 K in transport properties reproduces well the observed transport behavior only when SOC is included, attesting to the precision of the (delicate) calculations and the stoichiometry of the samples. Low-energy collective electron-hole excitations (plasmons) in the 20-60 meV range result from the nodal loop splitting.
13. Shifting nodal-plane suppressions in high-order-harmonic spectra from diatomic molecules in orthogonally polarized driving fields
Science.gov (United States)
Das, T.; Figueira de Morisson Faria, C.
2016-08-01
We analyze the imprint of nodal planes in high-order-harmonic spectra from aligned diatomic molecules in intense laser fields whose components exhibit orthogonal polarizations. We show that the typical suppression in the spectra associated to nodal planes is distorted, and that this distortion can be employed to map the electron's angle of return to its parent ion. This investigation is performed semianalytically at the single-molecule response and single-active orbital level, using the strong-field approximation and the steepest descent method. We show that the velocity form of the dipole operator is superior to the length form in providing information about this distortion. However, both forms introduce artifacts that are absent in the actual momentum-space wave function. Furthermore, elliptically polarized fields lead to larger distortions in comparison to two-color orthogonally polarized fields. These features are investigated in detail for O2, whose highest occupied molecular orbital provides two orthogonal nodal planes.
14. Numerical nodal simulation of the axial power distribution within nuclear reactors using a kinetics diffusion model. I
International Nuclear Information System (INIS)
Presented here is a new numerical nodal method for the simulation of the axial power distribution within nuclear reactors using the one-dimensional one speed kinetics diffusion model with one group of delayed neutron precursors. Our method is based on a spectral analysis of the nodal kinetics equations. These equations are obtained by integrating the original kinetics equations separately over a time step and over a spatial node, and then considering flat approximations for the forward difference terms. These flat approximations are the only approximations that are considered in the method. As a result, the spectral nodal method for space - time reactor kinetics generates numerical solutions for space independent problems or for time independent problems that are completely free from truncation errors. We show numerical results to illustrate the method's accuracy for coarse mesh calculations. (author)
15. Supercritical Airfoil Coordinates
Data.gov (United States)
National Aeronautics and Space Administration — Rectangular Supercritical Wing (Ricketts) - design and measured locations are provided in an Excel file RSW_airfoil_coordinates_ricketts.xls . One sheet is with Non...
16. Dimensions of Organizational Coordination
DEFF Research Database (Denmark)
Jensen, Andreas Schmidt; Aldewereld, Huib; Dignum, Virginia
2013-01-01
be supported to include organizational objectives and constraints into their reasoning processes by considering two alternatives: agent reasoning and middleware regulation. We show how agents can use an organizational specification to achieve organizational objectives by delegating and coordinating...
17. Understanding social motor coordination.
Science.gov (United States)
Schmidt, R C; Fitzpatrick, Paula; Caron, Robert; Mergeche, Joanna
2011-10-01
Recently there has been much interest in social coordination of motor movements, or as it is referred to by some researchers, joint action. This paper reviews the cognitive perspective's common coding/mirror neuron theory of joint action, describes some of its limitations and then presents the behavioral dynamics perspective as an alternative way of understanding social motor coordination. In particular, behavioral dynamics' ability to explain the temporal coordination of interacting individuals is detailed. Two experiments are then described that demonstrate how dynamical processes of synchronization are apparent in the coordination underlying everyday joint actions such as martial art exercises, hand-clapping games, and conversations. The import of this evidence is that emergent dynamic patterns such as synchronization are the behavioral order that any neural substrate supporting joint action (e.g., mirror systems) would have to sustain.
18. The curvature coordinate system
DEFF Research Database (Denmark)
Almegaard, Henrik
2007-01-01
The paper describes a concept for a curvature coordinate system on regular curved surfaces from which faceted surfaces with plane quadrangular facets can be designed. The lines of curvature are used as parametric lines for the curvature coordinate system on the surface. A new conjugate set of lines......, called middle curvature lines, is introduced. These lines define the curvature coordinate system. Using the curvature coordinate system, the surface can be conformally mapped on the plane. In this mapping, elliptic sections are mapped as circles, and hyperbolic sections are mapped as equilateral...... hyperbolas. This means that when a plane orthogonal system of curves for which the vertices in a mesh always lie on a circle is mapped on a surface with positive Gaussian curvature using inverse mapping, and the mapped vertices are connected by straight lines, this network will form a faceted surface...
19. Coordinating Work with Groupware
DEFF Research Database (Denmark)
Pors, Jens Kaaber; Simonsen, Jesper
2003-01-01
One important goal of employing groupware is to make possible complex collaboration between geographically distributed groups. This requires a dual transformation of both technology and work practice. The challenge is to reduce the complexity of the coordination work by successfully inte....... Using the CSCW framework of coordination mechanisms, we have elicited six general factors influencing the integration of the groupware application in two situations....
20. Attribute coordination in organizations
OpenAIRE
Yingyi Qian; Gerard Roland; Chenggang Xu
2001-01-01
We study coordination in organizations with a variety of organizational forms. Coordination in organization is modeled as the adjustment of attributes and capacities of tasks when facing external shocks. An M-form (U-form) organization groups complementary (substitutable) tasks together in one unit. In the presence of only attribute shocks, particularly when gains from specialization are small, communication is poor, or shocks are more likely, the expected payoff of the decentralized M-form i...
1. Indication of lower neck irradiation in nasopharyngeal carcinoma without nodal metastasis: the potential impact of tumor volume
Institute of Scientific and Technical Information of China (English)
FU Jie; ZHOU Jia-yin; Vincent FH CHONG; James BK Khoo
2013-01-01
Background Elective radiation of lower neck is controversial for nasopharyngeal carcinoma (NPC) without lymph node metastasis (N0 disease).Tumor volume is an important prognostic indicator.The objective of this study is to explore the potential impact of tumor volume on the indication of the lower neck irradiation for N0-NPC,by a qualitative evaluation of the relationship between tumor volume and nodal metastasis.Methods Magnetic resonance (MR) images of 99 consecutive patients with NPC who underwent treatment were retrospectively reviewed.Primary tumor volumes of NPC were semi-automatically measured,nodal metastases were N-classified and neck level involvements were examined.Distributions of tumor volumes among N-category-based groups and distributions of N-categories among tumor volume-based groups were analyzed,respectively.Results The numbers of patients with N0 to N3 disease were 12,39,32,and 16,respectively.The volumes of primary tumor were from 3.3 to 89.6 ml,with a median of 17.1 ml.For patients with nodal metastasis,tumor volume did not increase significantly with the advancing of N-category (P ＞0.05).No significant difference was found for the distribution of N1,N2,and N3 categories among tumor volume-based groups (P ＞0.05).Nevertheless patients with nodal metastasis had significantly larger tumor volumes than those without metastasis (P ＜0.05).Patients with larger tumor volumes were associated with an increased incidence of nodal metastasis.Conclusions Certain positive correlations existed between tumor volume and the presence of nodal metastasis.The tumor volume (＞10 ml) is a potential indicator for the lower neck irradiation for N0-NPC.
2. Prevalence and pattern of nodal metastasis in pT4 gingivobuccal cancers and its implications for treatment
Directory of Open Access Journals (Sweden)
H Narendra
2010-01-01
Full Text Available Context: The pattern of nodal spread in oral cancers is largely predictable and treatment of neck can be tailored with this knowledge. Most studies available on the pattern are from the western world and for early cancers of the tongue and floor of the mouth. Aims: The present study was aimed to evaluate the prevalence and pattern of nodal metastasis in patients with pathologic T4 (pT4 buccal/alveolar cancers. Settings and Design: Medical records of the patients with pT4 primary buccal and alveolar squamous cell carcinomas treated by single-stage resection of primary tumor and neck dissection at Gujarat Cancer and Research Institute (GCRI, Ahmedabad, a regional cancer center in India, during September 2004 to August 2006, were analyzed for nodal involvement. Materials and Methods: The study included 127 patients with pT4 buccal/alveolar cancer. Data pertaining to clinical nodal status, histologic grade, pT and pN status (TNM classification of malignant tumors, UICC, 6th edition, 2002, total number of nodes removed, and those involved by tumor, and levels of nodal involvement were recorded. Statistical analysis was performed using the Chi-square test. Results: Fifty percent of the patients did not have nodal metastasis on final histopathology. Occult metastasis rate was 23%. All of these occurred in levels I to III. Among those with clinically palpable nodes, level V involvement was seen only in 4% of the patients with pT4 buccal cancer and 3% of the patients with alveolar cancer. Conclusions: Elective treatment of the neck in the form of selective neck dissection of levels I to III is needed for T4 cancers of gingivobuccal complex due to a high rate of occult metastasis. Selected patients with clinically involved nodes could be well served by a selective neck dissection incorporating levels I to III or IV.
3. Absolute Humidity and the Seasonality of Influenza (Invited)
Science.gov (United States)
Shaman, J. L.; Pitzer, V.; Viboud, C.; Grenfell, B.; Goldstein, E.; Lipsitch, M.
2010-12-01
Much of the observed wintertime increase of mortality in temperate regions is attributed to seasonal influenza. A recent re-analysis of laboratory experiments indicates that absolute humidity strongly modulates the airborne survival and transmission of the influenza virus. Here we show that the onset of increased wintertime influenza-related mortality in the United States is associated with anomalously low absolute humidity levels during the prior weeks. We then use an epidemiological model, in which observed absolute humidity conditions temper influenza transmission rates, to successfully simulate the seasonal cycle of observed influenza-related mortality. The model results indicate that direct modulation of influenza transmissibility by absolute humidity alone is sufficient to produce this observed seasonality. These findings provide epidemiological support for the hypothesis that absolute humidity drives seasonal variations of influenza transmission in temperate regions. In addition, we show that variations of the basic and effective reproductive numbers for influenza, caused by seasonal changes in absolute humidity, are consistent with the general timing of pandemic influenza outbreaks observed for 2009 A/H1N1 in temperate regions. Indeed, absolute humidity conditions correctly identify the region of the United States vulnerable to a third, wintertime wave of pandemic influenza. These findings suggest that the timing of pandemic influenza outbreaks is controlled by a combination of absolute humidity conditions, levels of susceptibility and changes in population mixing and contact rates.
4. Supplementary and Enrichment Series: Absolute Value. Teachers' Commentary. SP-25.
Science.gov (United States)
Bridgess, M. Philbrick, Ed.
This is one in a series of manuals for teachers using SMSG high school supplementary materials. The pamphlet includes commentaries on the sections of the student's booklet, answers to the exercises, and sample test questions. Topics covered include addition and multiplication in terms of absolute value, graphs of absolute value in the Cartesian…
5. Supplementary and Enrichment Series: Absolute Value. SP-24.
Science.gov (United States)
Bridgess, M. Philbrick, Ed.
This is one in a series of SMSG supplementary and enrichment pamphlets for high school students. This series is designed to make material for the study of topics of special interest to students readily accessible in classroom quantity. Topics covered include absolute value, addition and multiplication in terms of absolute value, graphs of absolute…
6. ABSOLUTE STABILITY OF GENERAL LURIE DISCRETE NONLINEAR CONTROL SYSTEMS
Institute of Scientific and Technical Information of China (English)
GAN Zuoxin; HAN Jingqing; ZHAO Suxia; WU Yongxian
2002-01-01
In the present paper, the absolute stability of general Lurie discrete nonlinear control systems has been discussed by Lyapunov function approach. A sufficient condition of absolute stability for the general Lurie discrete nonlinear control systems is derived, and some necessary and sufficient conditions are obtained in special cases. Meanwhile, we give a simple example to illustrate the effectiveness of the results.
7. Novalis' Poetic Uncertainty: A "Bildung" with the Absolute
Science.gov (United States)
Mika, Carl
2016-01-01
Novalis, the Early German Romantic poet and philosopher, had at the core of his work a mysterious depiction of the "absolute." The absolute is Novalis' name for a substance that defies precise knowledge yet calls for a tentative and sensitive speculation. How one asserts a truth, represents an object, and sets about encountering things…
8. Absolute neutronic performance of SNS from gold foil application
International Nuclear Information System (INIS)
The determination of absolute neutron fluxes by white beam activation of thick gold foils in conjuction with spectral analysis by time-of-flight monitors is described. A numerical integration procedure is presented and the method applied to determining the absolute performance of SNS from data obtained during the initial commissioning run in December 1984. (author)
9. Continuous parallel coordinates.
Science.gov (United States)
Heinrich, Julian; Weiskopf, Daniel
2009-01-01
Typical scientific data is represented on a grid with appropriate interpolation or approximation schemes,defined on a continuous domain. The visualization of such data in parallel coordinates may reveal patterns latently contained in the data and thus can improve the understanding of multidimensional relations. In this paper, we adopt the concept of continuous scatterplots for the visualization of spatially continuous input data to derive a density model for parallel coordinates. Based on the point-line duality between scatterplots and parallel coordinates, we propose a mathematical model that maps density from a continuous scatterplot to parallel coordinates and present different algorithms for both numerical and analytical computation of the resulting density field. In addition, we show how the 2-D model can be used to successively construct continuous parallel coordinates with an arbitrary number of dimensions. Since continuous parallel coordinates interpolate data values within grid cells, a scalable and dense visualization is achieved, which will be demonstrated for typical multi-variate scientific data.
10. Continuous parallel coordinates.
Science.gov (United States)
Heinrich, Julian; Weiskopf, Daniel
2009-01-01
Typical scientific data is represented on a grid with appropriate interpolation or approximation schemes,defined on a continuous domain. The visualization of such data in parallel coordinates may reveal patterns latently contained in the data and thus can improve the understanding of multidimensional relations. In this paper, we adopt the concept of continuous scatterplots for the visualization of spatially continuous input data to derive a density model for parallel coordinates. Based on the point-line duality between scatterplots and parallel coordinates, we propose a mathematical model that maps density from a continuous scatterplot to parallel coordinates and present different algorithms for both numerical and analytical computation of the resulting density field. In addition, we show how the 2-D model can be used to successively construct continuous parallel coordinates with an arbitrary number of dimensions. Since continuous parallel coordinates interpolate data values within grid cells, a scalable and dense visualization is achieved, which will be demonstrated for typical multi-variate scientific data. PMID:19834230
11. Magnetic Coordinate Systems
Science.gov (United States)
Laundal, K. M.; Richmond, A. D.
2016-07-01
Geospace phenomena such as the aurora, plasma motion, ionospheric currents and associated magnetic field disturbances are highly organized by Earth's main magnetic field. This is due to the fact that the charged particles that comprise space plasma can move almost freely along magnetic field lines, but not across them. For this reason it is sensible to present such phenomena relative to Earth's magnetic field. A large variety of magnetic coordinate systems exist, designed for different purposes and regions, ranging from the magnetopause to the ionosphere. In this paper we review the most common magnetic coordinate systems and describe how they are defined, where they are used, and how to convert between them. The definitions are presented based on the spherical harmonic expansion coefficients of the International Geomagnetic Reference Field (IGRF) and, in some of the coordinate systems, the position of the Sun which we show how to calculate from the time and date. The most detailed coordinate systems take the full IGRF into account and define magnetic latitude and longitude such that they are constant along field lines. These coordinate systems, which are useful at ionospheric altitudes, are non-orthogonal. We show how to handle vectors and vector calculus in such coordinates, and discuss how systematic errors may appear if this is not done correctly.
12. Phase I Trial of Pelvic Nodal Dose Escalation With Hypofractionated IMRT for High-Risk Prostate Cancer
Energy Technology Data Exchange (ETDEWEB)
Adkison, Jarrod B.; McHaffie, Derek R.; Bentzen, Soren M.; Patel, Rakesh R.; Khuntia, Deepak [Department of Human Oncology, University of Wisconsin Carbone Cancer Center, School of Medicine and Public Health, Madison, WI (United States); Petereit, Daniel G. [Department of Radiation Oncology, John T. Vucurevich Regional Cancer Care Institute, Rapid City Regional Hospital, Rapid City, SD (United States); Hong, Theodore S.; Tome, Wolfgang [Department of Human Oncology, University of Wisconsin Carbone Cancer Center, School of Medicine and Public Health, Madison, WI (United States); Ritter, Mark A., E-mail: ritter@humonc.wisc.edu [Department of Human Oncology, University of Wisconsin Carbone Cancer Center, School of Medicine and Public Health, Madison, WI (United States)
2012-01-01
13. Nodal Gap” Induced by the Incommensurate Diagonal Spin Density Modulation in Underdoped High-Tc Superconductors
Directory of Open Access Journals (Sweden)
Tao Zhou
2015-01-01
Full Text Available Recently it was revealed that the whole Fermi surface is fully gapped for several families of underdoped cuprates. The existence of the finite energy gap along the d-wave nodal lines (nodal gap contrasts the common understanding of the d-wave pairing symmetry, which challenges the present theories for the high-Tc superconductors. Here we propose that the incommensurate diagonal spin-density-wave order can account for the above experimental observation. The Fermi surface and the local density of states are also studied. Our results are in good agreement with many important experiments in high-Tc superconductors.
14. Numerical Solution of Poroelastic Wave Equation Using Nodal Discontinuous Galerkin Finite Element Method
Science.gov (United States)
Shukla, K.; Wang, Y.; Jaiswal, P.
2014-12-01
In a porous medium the seismic energy not only propagates through matrix but also through pore-fluids. The differential movement between sediment grains of the matrix and interstitial fluid generates a diffusive wave which is commonly referred to as the slow P-wave. A combined system of equation which includes both elastic and diffusive phases is known as the poroelasticity. Analyzing seismic data through poroelastic modeling results in accurate interpretation of amplitude and separation of wave modes, leading to more accurate estimation of geomehanical properties of rocks. Despite its obvious multi-scale application, from sedimentary reservoir characterization to deep-earth fractured crust, poroelasticity remains under-developed primarily due to the complex nature of its constituent equations. We present a detail formulation of poroleastic wave equations for isotropic media by combining the Biot's and Newtonian mechanics. System of poroelastic wave equation constitutes for eight time dependent hyperbolic PDEs in 2D whereas in case of 3D number goes up to thirteen. Eigen decomposition of Jacobian of these systems confirms the presence of an additional slow-P wave phase with velocity lower than shear wave, posing stability issues on numerical scheme. To circumvent the issue, we derived a numerical scheme using nodal discontinuous Galerkin approach by adopting the triangular meshes in 2D which is extended to tetrahedral for 3D problems. In our nodal DG approach the basis function over a triangular element is interpolated using Legendre-Gauss-Lobatto (LGL) function leading to a more accurate local solutions than in the case of simple DG. We have tested the numerical scheme for poroelastic media in 1D and 2D case, and solution obtained for the systems offers high accuracy in results over other methods such as finite difference , finite volume and pseudo-spectral. The nodal nature of our approach makes it easy to convert the application into a multi-threaded algorithm
15. STEP- A three-dimensional nodal diffusion code for LMR's
Energy Technology Data Exchange (ETDEWEB)
Kim, Yeong Il; Kim, Taek Kyum [Korea Atomic Energy Research Institute, Taejon (Korea)
1999-12-01
STEP is a three-dimensional multigroup nodal diffusion code for the neutronics analysis of the LMR core. STEP employs DIF3D and HEXNOD nodal methods. In DIF3D, one-dimensional fluxes are approximated by polynomials while HEXNOD analytically solves transverse-integrated one-dimensional diffusion equations. The nodal equations are solved using a conventional fission source iteration procedure accelerated by coarse-mesh rebalancing and asymptotic extrapolation. At each fission source iteration, the interface currents for each group are computed by solving the response matrix equations with a known group source term. These partial currents are used to updata flux moments. This solution is accomplished by inner iteration, a series of sweeps through the spatial mesh. Inner iterations are performed by sweeping the axial mesh plane in a standard red-black checkerboard ordering, i.e. the odd-numbered planes are processed during the first pass, followed by the even-numbered planes on the second pass. On each plane, the nodes are swept in the four-color checkerboard ordering. STEP accepts microscopic cross section data from the CCCC standard interface file ISOTXS currently used for the neutronics analysis of LMR's at KAERI as well as macroscopic cross section data. Material cross sections are obtained by summing the product of atom densities and microscopic cross sections over all isotopes comprising the material. Energy is released from both fission ad capture. The thermal-hydraulics model calculates average fuel and coolant temperatures. STEP takes account of feedback effects from both fuel temperature and coolant temperature changes. The thermal-hydraulics model is a conservative, single channel model where there is no heat transfer between assemblies. Thus, STEP gives conservative results which, however, are of useful information for core design and can be useful tool for neutronics analysis of LMR core design and will be used for the base program of a future
16. Rbb4l enhances TGF-β/Nodal signaling and promotes zebrafish embryonic dorsolization%Rbb4l 促进TGF-β/Nodal 信号转导和斑马鱼胚胎的背部发育
Institute of Scientific and Technical Information of China (English)
佟静媛; 柳星峰; 贾顺姬
2013-01-01
The TGF-β/Nodal signaling pathway plays an important role in the zebrafish dorsoventral patterning process. To further explore the function and mechanism of this signaling pathway, we identified a set of Smad2/3a interacting proteins by the yeast two-hybrid screen. Rbb41 (Retinoblastoma binding protein 4, like) is one of the identified proteins. Human RBBP4 (Retinoblastoma binding protein 4), the homolog of zebrafish Rbb41, has been shown to form complexes with other chromatin modifiers, but its roles in embryonic development remain unknown. In this study, we showed that Rbb41 directly interacted with Smad3a and enhances TGF-β/Nodal signaling. In zebrafish embryos, rbb4l overexpression resulted in an expanded expression of dorsal markers with a reduction of ventral markers expression, suggesting a dorsalizing function. On the contrary, rbb4l knockdown caused ventralized phenotype of the embryos at 24 hours post-fertilization (hpf). Furthermore, a series of rescue experiments showed that rbb4l failed to cause embryonic dorsalization in the absence of Nodal signal. Together, our data suggested that Rbb41 acts as an enhancer of Nodal/Smad.2/3 signaling during embryogene-sis, and depends on the existence of Nodal signaling.%TGF-β/Nodal 信号通路在斑马鱼胚胎背腹分化过程中发挥重要作用.为了进一步探究该信号通路的功能及作用机制,文章采用酵母双杂交的方法,以斑马鱼Smad2/3a 为诱饵蛋白筛选得到一系列Smad2/3a 的互作蛋白,其中之一为Rbb4l (Retinoblastoma binding protein 4,like).已有的报道表明,Rbb4l 的人类同源蛋白RBBP4(Retinoblastoma binding protein 4) 是染色质修饰相关的复合体的组成成分,但它在脊椎动物胚胎发育过程中的作用还知之甚少.文章通过体外及体内的一系列实验表明,Rbb4l 能直接与Smad3a 互作,增强TGF-β/Nodal 信号.在斑马鱼胚胎中过表达rbb4l 导致胚胎的背部化,伴随着背部标记基因表达区域的扩大和
17. Absolute brightness temperature measurements at 2.1-mm wavelength
Science.gov (United States)
Ulich, B. L.
1974-01-01
Absolute measurements of the brightness temperatures of the Sun, new Moon, Venus, Mars, Jupiter, Saturn, and Uranus, and of the flux density of DR21 at 2.1-mm wavelength are reported. Relative measurements at 3.5-mm wavelength are also preented which resolve the absolute calibration discrepancy between The University of Texas 16-ft radio telescope and the Aerospace Corporation 15-ft antenna. The use of the bright planets and DR21 as absolute calibration sources at millimeter wavelengths is discussed in the light of recent observations.
18. An All Fiber White Light Interferometric Absolute Temperature Measurement System
Directory of Open Access Journals (Sweden)
Jeonggon Harrison Kim
2008-11-01
Full Text Available Recently the author of this article proposed a new signal processing algorithm for an all fiber white light interferometer. In this article, an all fiber white light interferometric absolute temperature measurement system is presented using the previously proposed signal processing algorithm. Stability and absolute temperature measurement were demonstrated. These two tests demonstrated the feasibility of absolute temperature measurement with an accuracy of 0.015 fringe and 0.0005 fringe, respectively. A hysteresis test from 373K to 873K was also presented. Finally, robustness of the sensor system towards laser diode temperature drift, AFMZI temperature drift and PZT non-linearity was demonstrated.
19. Topological semimetals with triply degenerate nodal points in θ -phase tantalum nitride
Science.gov (United States)
Weng, Hongming; Fang, Chen; Fang, Zhong; Dai, Xi
2016-06-01
Using first-principles calculation and symmetry analysis, we propose that θ -TaN is a topological semimetal having a new type of point nodes, i.e., triply degenerate nodal points. Each node is a band crossing between degenerate and nondegenerate bands along the high-symmetry line in the Brillouin zone, and is protected by crystalline symmetries. Such new type of nodes will always generate singular touching points between different Fermi surfaces and three-dimensional spin texture around them. Breaking the crystalline symmetry by external magnetic field or strain leads to various topological phases. By studying the Landau levels under a small field along the c axis, we demonstrate that the system has a new quantum anomaly that we call "helical anomaly.'
20. Quantum criticality and nodal superconductivity in the FeAs-based superconductor KFe2As2.
Science.gov (United States)
Dong, J K; Zhou, S Y; Guan, T Y; Zhang, H; Dai, Y F; Qiu, X; Wang, X F; He, Y; Chen, X H; Li, S Y
2010-02-26
The in-plane resistivity rho and thermal conductivity kappa of the FeAs-based superconductor KFe2As2 single crystal were measured down to 50 mK. We observe non-Fermi-liquid behavior rho(T) approximately T{1.5} at H{c{2}}=5 T, and the development of a Fermi liquid state with rho(T) approximately T{2} when further increasing the field. This suggests a field-induced quantum critical point, occurring at the superconducting upper critical field H{c{2}}. In zero field, there is a large residual linear term kappa{0}/T, and the field dependence of kappa_{0}/T mimics that in d-wave cuprate superconductors. This indicates that the superconducting gaps in KFe2As2 have nodes, likely d-wave symmetry. Such a nodal superconductivity is attributed to the antiferromagnetic spin fluctuations near the quantum critical point.
1. Evaluation of nodal reliability risk in a deregulated power system with photovoltaic power penetration
DEFF Research Database (Denmark)
Zhao, Qian; Wang, Peng; Goel, Lalit;
2014-01-01
Owing to the intermittent characteristic of solar radiation, power system reliability may be affected with high photovoltaic (PV) power penetration. To reduce large variation of PV power, additional system balancing reserve would be needed. In deregulated power systems, deployment of reserves...... and customer reliability requirements are correlated with energy and reserve prices. Therefore a new method should be developed to evaluate the impacts of PV power on customer reliability and system reserve deployment in the new environment. In this study, a method based on the pseudo-sequential Monte Carlo...... simulation technique has been proposed to evaluate the reserve deployment and customers' nodal reliability with high PV power penetration. The proposed method can effectively model the chronological aspects and stochastic characteristics of PV power and system operation with high computation efficiency...
2. Vector Bundles with a Fixed Determinant on an Irreducible Nodal Curve
Usha N Bhosle
2005-11-01
Let be the moduli space of generalized parabolic bundles (GPBs) of rank and degree on a smooth curve . Let $M_{\\overline{L}}$ be the closure of its subset consisting of GPBs with fixed determinant $\\overline{L}$. We define a moduli functor for which $M_{\\overline{L}}$ is the coarse moduli scheme. Using the correspondence between GPBs on and torsion-free sheaves on a nodal curve of which is a desingularization, we show that $M_{\\overline{L}}$ can be regarded as the compactified moduli scheme of vector bundles on with fixed determinant. We get a natural scheme structure on the closure of the subset consisting of torsion-free sheaves with a fixed determinant in the moduli space of torsion-free sheaves on . The relation to Seshadri–Nagaraj conjecture is studied.
3. TOPS nodal code solutions for the OECD/PBMR-400 benchmark problem
Energy Technology Data Exchange (ETDEWEB)
Lee, J.; Lee, J. H.; Yoo, H. J.; Lee, G. S.; Cho, N. Z. [Korea Advanced Inst. of Science and Technology, 373-1 Kusong-dong, Yusong-gu, Daejeon (Korea, Republic of)
2006-07-01
This paper provides the solution of the OECD/PBMR-400 benchmark problem by the TOPS code based on the Analytic Function Expansion Nodal (AFEN) method in 3-D cylindrical geometry. The paper is focused on the multi-group methodology, two methods (partial current translation and AFEN formulation) of treating the void regions, and comparison of the their results. We also suggest a modified benchmark problem, which does not have void regions where special treatments are required, to be used to verify the calculational methods in cylindrical geometry. The results indicate that the effect of void regions is significant and that the method how to treat the voids in computation is important. (authors)
4. Micropropagation of Dianthus deltoides L. through shoot tip and nodal cuttings culture
Directory of Open Access Journals (Sweden)
Marković Marija
2013-01-01
Full Text Available Micropropagation (shoot tip and nodal cuttings culture was used for the rapid propagation of the non-invasive, decorative, native plants of maiden pink (Dianthus deltoides L. in order to preserve their genetic diversity. In vitro culture was successfully established on Murashige and Skoog medium (MS using seeds as the initial material. In the shoot multiplication phase, the explants were cultured on MS medium supplemented with different concentrations of 6-benzylaminopurine (BAP and naphthaleneacetic acid (NAA. The highest multiplication rate was achieved on a medium containing 0.1 mgL-1 of BAP and 0.1 mgL-1 of NAA. The rooting was successful on a hormone-free medium (100%, and the highest percentage of microplant acclimatization (97% was recorded in a 4: 1 mixture of peat and sand. [Projekat Ministarstva nauke Republike Srbije, br. TR 31041: Establishment of wood plantations intended for a forestation of Serbia
5. Sick sinus syndrome and atrial fibrillation in older persons - A view from the sinoatrial nodal myocyte.
Science.gov (United States)
Monfredi, O; Boyett, M R
2015-06-01
Sick sinus syndrome remains a highly relevant clinical entity, being responsible for the implantation of the majority of electronic pacemakers worldwide. It is an infinitely more complex disease than it was believed when first described in the mid part of the 20th century. It not only involves the innate leading pacemaker region of the heart, the sinoatrial node, but also the atrial myocardium, predisposing to atrial tachydysrhythmias. It remains controversial as to whether the dysfunction of the sinoatrial node directly causes the dysfunction of the atrial myocardium, or vice versa, or indeed whether these two aspects of the condition arise through some related underlying pathological mechanism, such as extracellular matrix remodeling, i.e., fibrosis. This review aims to shed new light on the myriad possible contributing factors in the development of sick sinus syndrome, with a particular focus on the sinoatrial nodal myocyte. This article is part of a Special Issue entitled CV Aging.
6. Micropropagation from cultured nodal explants of rose (Rosa hybrida L. cv. ‘Perfume Delight’
Directory of Open Access Journals (Sweden)
Kamnoon Kanchanapoom
2010-01-01
Full Text Available A method for the micropropagation of rose (Rosa hybrida L. cv. ‘Perfume Delight’ was developed. First to fifth nodal explants from young healthy shoots were excised and cultured on basal medium of Murashige and Skoog (1962, MS containing several concentrations of BA and NAA. Multiple shoot formation of up to 3 shoots was obtained on MS medium supplemented with 3 mg/l BA and 0.003 mg/l NAA. Shoot readily rooted on ¼MS medium devoid of growth regulators.Rooted plantlets were hardened and established in pots at 100% survival. In vitro flowering was observed on rose plantscultured on MS medium containing 3 mg/l BA and 0.003 mg/l NAA.
7. Isolated cutaneous involvement in a child with nodal anaplastic large cell lymphoma
Directory of Open Access Journals (Sweden)
Vibhu Mendiratta
2016-01-01
Full Text Available Non-Hodgkin lymphoma is a common childhood T-cell and B-cell neoplasm that originates primarily from lymphoid tissue. Cutaneous involvement can be in the form of a primary extranodal lymphoma, or secondary to metastasis from a non-cutaneous location. The latter is uncommon, and isolated cutaneous involvement is rarely reported. We report a case of isolated secondary cutaneous involvement from nodal anaplastic large cell lymphoma (CD30 + and ALK + in a 7-year-old boy who was on chemotherapy. This case is reported for its unusual clinical presentation as an acute febrile, generalized papulonodular eruption that mimicked deep fungal infection, with the absence of other foci of systemic metastasis.
8. A stabilised nodal spectral element method for fully nonlinear water waves
DEFF Research Database (Denmark)
Engsig-Karup, Allan Peter; Eskilsson, C.; Bigoni, Daniele
2016-01-01
We present an arbitrary-order spectral element method for general-purpose simulation of non-overturning water waves, described by fully nonlinear potential theory. The method can be viewed as a high-order extension of the classical finite element method proposed by Cai et al. (1998) [5], although...... the numerical implementation differs greatly. Features of the proposed spectral element method include: nodal Lagrange basis functions, a general quadrature-free approach and gradient recovery using global L2 projections. The quartic nonlinear terms present in the Zakharov form of the free surface conditions...... propagation. The benefit of using a high-order – possibly adapted – spatial discretisation for accurate water wave propagation over long times and distances is particularly attractive for marine hydrodynamics applications....
9. A Stabilised Nodal Spectral Element Method for Fully Nonlinear Water Waves
CERN Document Server
Engsig-Karup, Allan Peter; Bigoni, Daniele
2015-01-01
We present an arbitrary-order spectral element method for general-purpose simulation of non-overturning water waves, described by fully nonlinear potential theory. The method can be viewed as a high-order extension of the classical finite element method proposed by Cai et al (1998) \\cite{CaiEtAl1998}, although the numerical implementation differs greatly. Features of the proposed spectral element method include: nodal Lagrange basis functions, a general quadrature-free approach and gradient recovery using global $L^2$ projections. The quartic nonlinear terms present in the Zakharov form of the free surface conditions can cause severe aliasing problems and consequently numerical instability for marginally resolved or very steep waves. We show how the scheme can be stabilised through a combination of over-integration of the Galerkin projections and a mild spectral filtering on a per element basis. This effectively removes any aliasing driven instabilities while retaining the high-order accuracy of the numerical...
10. Ultrasound-guided fine-needle aspiration of suspicious nodes in breast cancer patients; selecting patients with extensive nodal involvement.
NARCIS (Netherlands)
Wely, B.J. van; Wilt, J.H.W. de; Schout, P.J.; Kooistra, B.; Wauters, Carla; Venderinck, D.; Strobbe, L.J.
2013-01-01
The aim of this study was to evaluate the value of Ultrasonography (US) guided fine-needle aspiration (FNA) of the axilla to identify breast cancer patients with extensive nodal involvement. A prospective database of breast cancer patients who underwent US-guided FNA of suspicious nodes, diagnosed b
11. IN VITRO REGENERATION FROM SHOOT TIP AND NODAL EXPLANTS OF SIMAROUBA GLAUCA DC, A PROMISING BIODIESEL TREE
Directory of Open Access Journals (Sweden)
Shastri P. Shukla
2013-03-01
Full Text Available An efficient regeneration protocol was developed from shoot tip and nodal explants of Simarouba glauca DC, a promising biodiesel plant. Nodal explants appeared to have better regeneration capacity than shoot tip explants (40% in the tested media. The highest regeneration frequency (90% and shoot number (7.00 ± 1.00 shoots per explants were obtained in nodal explants in Murashige and Skoog’s (MS medium supplemented with 6-benzylaminopurine (BAP 4.43 μM and α-naphthalene acetic acid (NAA 5.36 μM.Induced shoot buds were multiplied and elongated on the MS medium supplemented with BAP (4.44 μM, NAA (5.36 μM and TDZ (Thidiazuron 2.27 μM with 9.66±0.33 (mean length 5.35±0.32 cm and 9.00±0.57 (mean length 4.51±0.15cm shoots using nodal segments and shoot tip explants, respectively. Halfstrength woody plant medium (WPM containing 2.46μM indole-3-butyric acid (IBA produced the maximum number of roots (6.00±1.15. The rooted plantlets were hardened on MS basal liquid medium and subsequently in polycups containing sterile soil and vermiculite (1:1 and successfully established in pots.
12. Nodal signalling in Xenopus: the role of Xnr5 in left/right asymmetry and heart development.
Science.gov (United States)
Tadjuidje, Emmanuel; Kofron, Matthew; Mir, Adnan; Wylie, Christopher; Heasman, Janet; Cha, Sang-Wook
2016-08-01
Nodal class TGF-β signalling molecules play essential roles in establishing the vertebrate body plan. In all vertebrates, nodal family members have specific waves of expression required for tissue specification and axis formation. In Xenopus laevis, six nodal genes are expressed before gastrulation, raising the question of whether they have specific roles or act redundantly with each other. Here, we examine the role of Xnr5. We find it acts at the late blastula stage as a mesoderm inducer and repressor of ectodermal gene expression, a role it shares with Vg1. However, unlike Vg1, Xnr5 depletion reduces the expression of the nodal family member xnr1 at the gastrula stage. It is also required for left/right laterality by controlling the expression of the laterality genes xnr1, antivin (lefty) and pitx2 at the tailbud stage. In Xnr5-depleted embryos, the heart field is established normally, but symmetrical reduction in Xnr5 levels causes a severely stunted midline heart, first evidenced by a reduction in cardiac troponin mRNA levels, while left-sided reduction leads to randomization of the left/right axis. This work identifies Xnr5 as the earliest step in the signalling pathway establishing normal heart laterality in Xenopus. PMID:27488374
13. Detection of Melanoma Nodal Metastases; Differences in Detection Between Elderly and Younger Patients Do Not Affect Survival
NARCIS (Netherlands)
Kruijff, S.; Bastiaannet, E.; Suurmeijer, A. J. H.; Hoekstra, H. J.
2010-01-01
Background. Melanoma lymph nodes metastases may be detected by patients or by physicians. Understanding the outcomes of self-detection or physician detection is essential for the design of follow-up studies. We evaluated the role of the method of detection in nodal disease in the prognosis of melano
14. Sensitivity of Nodal Admittances in an Offshore Wind Power Plant to Parametric Variations in the Collection Grid
DEFF Research Database (Denmark)
Vytautas, Kersiulis; Holdyk, Andrzej; Holbøll, Joachim;
2012-01-01
The paper presents sensitivity studies on nodal admittances in the offshore wind farm to different parameters of the collection grid cable system, including length of cable sections and actual layout configuration. The main aspect of this investigation is to see how parametric variations influence...
15. Verification of the Advanced Nodal Method on BWR Core Analyses by Whole-Core Heterogeneous Transport Calculations
International Nuclear Information System (INIS)
Recent boiling water reactor (BWR) core and fuel designs have become more sophisticated and heterogeneous to improve fuel cycle cost, thermal margin, etc. These improvements, however, tend to lead to a strong interference effect among fuel assemblies, and it my cause some inaccuracies in the BWR core analyses by advanced nodal codes. Furthermore, the introduction of mixed-oxide (MOX) fuel will lead to a much stronger interference effect between MOX and UO2 fuel assemblies. However, the CHAPLET multiassembly characteristics transport code was developed recently to solve two-dimensional cell-heterogeneous whole-core problems efficiently, and its results can be used as reference whole-core solutions to verify the accuracy of nodal core calculations. In this paper, the results of nodal core calculations were compared with their reference whole-core transport solutions to verify their accuracy (in keff, assembly power and pin power via pin power reconstruction) of the advanced nodal method on both UO2 and MOX BWR whole-core analyses. Especially, it was investigated if there were any significant differences in the accuracy between MOX and UO2 results
16. Transcriptomic analysis of Nodal- and BMP-associated genes during juvenile development of the sea urchin Heliocidaris erythrogramma.
Science.gov (United States)
Byrne, Maria; Koop, Demian; Cisternas, Paula; Strbenac, Dario; Yang, Jean Yee Hwa; Wray, Gregory A
2015-12-01
Understanding the unusual radial body plan of echinoderms and its relationship to the bilateral plan of other deuterostomes remains a challenge. The molecular processes of embryonic and early larval development in sea urchins are well characterised, but those giving rise to the adult and its radial body remain poorly studied. We used the developmental transcriptome generated for Heliocidaris erythrogramma, a species that forms the juvenile soon after gastrulation, to investigate changes in gene expression underlying radial body development. As coelomogenesis is key to the development of pentamery and juvenile formation on the left side of the larva, we focussed on genes associated with the nodal and BMP2/4 network that pattern this asymmetry. We identified 46 genes associated with this Nodal and BMP2/4 signalling network, and determined their expression profiles from the gastrula, through to rudiment development, metamorphosis and the fully formed juvenile. Genes associated with Nodal signalling shared similar expression profiles, indicating that they may have a regulatory relationship in patterning morphogenesis of the juvenile sea urchin. Similarly, many genes associated with BMP2/4 signalling had similar expression profiles through juvenile development. Further examination of the roles of Nodal- and BMP2/4-associated genes is required to determine function and whether the gene expression profiles seen in H. erythrogramma are due to ongoing activity of gene networks established during early development, or to redeployment of regulatory cassettes to pattern the adult radial body plan.
17. Identification and expression of Smads associated with TGF-beta/activin/nodal signaling pathways in the rainbow trout (Oncorhynuchus mykiss)
Science.gov (United States)
18. The effects of pruning and nodal adventitious roots on polychlorinated biphenyl uptake by Cucurbita pepo grown in field conditions
International Nuclear Information System (INIS)
Two cultivation techniques (i-pruning and ii-nodal adventitious root encouragement) were investigated for their ability to increase PCB phytoextraction by Cucurbita pepo ssp pepo cv. Howden (pumpkin) plants in situ at a contaminated industrial site in Ontario (Aroclor 1248, mean soil [PCB] = 5.6 μg g-1). Pruning was implemented to increase plant biomass close to the root where PCB concentration is known to be highest. This treatment was found to have no effect on final shoot biomass or PCB concentration. However, material pruned from the plant is not included in the final shoot biomass. The encouragement of nodal adventitious roots at stem nodes did significantly increase the PCB concentration in the primary stem, while not affecting shoot biomass. Both techniques are easily applied cultivation practices that may be implemented to decrease phytoextraction treatment time. - Research highlights: → Presence of nodal adventitious roots do increase phytoextraction efficiency. → Pruning may increase the biomass of pumpkin plants during phytoextraction. → [Aroclor 1248] decreases in plant tissue with increasing distance from the root. - The application of cultivation practices (pruning and nodal adventitious root encouragement) increases phytoextraction of PCBs in C. pepo.
19. Quantifying linguistic coordination
DEFF Research Database (Denmark)
Fusaroli, Riccardo; Tylén, Kristian
). We employ nominal recurrence analysis (Orsucci et al 2005, Dale et al 2011) on the decision-making conversations between the participants. We report strong correlations between various indexes of recurrence and collective performance. We argue this method allows us to quantify the qualities......Language has been defined as a social coordination device (Clark 1996) enabling innovative modalities of joint action. However, the exact coordinative dynamics over time and their effects are still insufficiently investigated and quantified. Relying on the data produced in a collective decision...
20. Coordinate Standard Measurement Development
Energy Technology Data Exchange (ETDEWEB)
Hanshaw, R.A.
2000-02-18
A Shelton Precision Interferometer Base, which is used for calibration of coordinate standards, was improved through hardware replacement, software geometry error correction, and reduction of vibration effects. Substantial increases in resolution and reliability, as well as reduction in sampling time, were achieved through hardware replacement; vibration effects were reduced substantially through modification of the machine component dampening and software routines; and the majority of the machine's geometry error was corrected through software geometry error correction. Because of these modifications, the uncertainty of coordinate standards calibrated on this device has been reduced dramatically.
1. Introduction to Coordination Chemistry
CERN Document Server
Lawrance, Geoffrey Alan
2010-01-01
Introduction to Coordination Chemistry examines and explains how metals and molecules that bind as ligands interact, and the consequences of this assembly process. This book describes the chemical and physical properties and behavior of the complex assemblies that form, and applications that may arise as a result of these properties. Coordination complexes are an important but often hidden part of our world?even part of us?and what they do is probed in this book. This book distills the essence of this topic for undergraduate students and for research scientists.
2. A posteriori error estimator and AMR for discrete ordinates nodal transport methods
Energy Technology Data Exchange (ETDEWEB)
Duo, Jose I. [The Pennsylvania State University, 138 Reber Bldg, University Park (United States); Azmy, Yousry Y. [The Pennsylvania State University, 229 Reber Bldg, University Park (United States); Zikatanov, Ludmil T. [The Pennsylvania State University, 218 McAllister Bldg, University Park (United States)
2008-07-01
In the development of high fidelity transport solvers, optimization of the use of available computational resources and access to a tool for assessing quality of the solution are key to the success of large-scale nuclear systems' simulation. Error control provides the analyst with a confidence level in the numerical solution and enables for optimization of resources through Adaptive Mesh Refinement (AMR). In this paper, we derive an a posterior error estimator based on the nodal solution of the Arbitrarily High Order Transport Method of the Nodal type (AHOT-N). Furthermore, by making assumptions on the regularity of the solution, we represent the error estimator as a function of computable volume and element-edges residuals. The global L{sub 2} error norm is proved to be bound by the estimator. To lighten the computational load, we present a numerical approximation to the aforementioned residuals and split the global norm error estimator into local error indicators. These indicators are used to drive an AMR strategy for the spatial discretization. However, the indicators based on forward solution residuals alone do not bound the cell-wise error. The estimator and AMR strategy are tested in two problems featuring strong heterogeneity and highly transport streaming regime with strong flux gradients. The results show that the error estimator indeed bounds the global error norms and that the error indicator follows the cell-error's spatial distribution pattern closely. The AMR strategy proves beneficial to optimize resources, primarily by reducing the number of discrete variables unknowns solved for to achieve a prescribed solution accuracy in global L{sub 2} error norm. Likewise, AMR achieves higher accuracy compared to uniform refinement when resolving sharp flux gradients, for the same number of unknowns. (authors)
3. A posteriori error estimator and AMR for discrete ordinates nodal transport methods
Energy Technology Data Exchange (ETDEWEB)
Duo, Jose I. [Westinghouse Electric Co., 4350 Northern Pike, Monroeville, PA 15146 (United States)], E-mail: duoji@westinghouse.com; Azmy, Yousry Y. [North Carolina State University, 1110 Burlington Lab., Raleigh, NC 27695-7909 (United States)], E-mail: yyazmy@ncsu.edu; Zikatanov, Ludmil T. [The Pennsylvania State University, 218 McAllister Bldg, University Park (United States)
2009-04-15
In the development of high fidelity transport solvers, optimization of the use of available computational resources and access to a tool for assessing quality of the solution are key to the success of large-scale nuclear systems' simulation. In this regard, error control provides the analyst with a confidence level in the numerical solution and enables for optimization of resources through Adaptive Mesh Refinement (AMR). In this paper, we derive an a posteriori error estimator based on the nodal solution of the Arbitrarily High Order Transport Method of the Nodal type (AHOT-N). Furthermore, by making assumptions on the regularity of the solution, we represent the error estimator as a function of computable volume and element-edges residuals. The global L{sub 2} error norm is proved to be bound by the estimator. To lighten the computational load, we present a numerical approximation to the aforementioned residuals and split the global norm error estimator into local error indicators. These indicators are used to drive an AMR strategy for the spatial discretization. However, the indicators based on forward solution residuals alone do not bound the cell-wise error. The estimator and AMR strategy are tested in two problems featuring strong heterogeneity and highly transport streaming regime with strong flux gradients. The results show that the error estimator indeed bounds the global error norms and that the error indicator follows the cell-error's spatial distribution pattern closely. The AMR strategy proves beneficial to optimize resources, primarily by reducing the number of unknowns solved for to achieve prescribed solution accuracy in global L{sub 2} error norm. Likewise, AMR achieves higher accuracy compared to uniform refinement when resolving sharp flux gradients, for the same number of unknowns.
4. Nodal vascularity as an indicator of cervicofacial metastasis in oral cancer: A Doppler sonographic study
Directory of Open Access Journals (Sweden)
Ankur Aggarwal
2014-01-01
Full Text Available Background: The objective of this study was to assess nodal vascularity by Doppler sonography and to find out the correlation between clinical and various Doppler sonographic features for the detection of the metastatic nodes in oral cancer patients. Patients and Methods: A total number of 55 patients of histopathologically proven oral cancer presenting with enlarged superficial cervicofacial lymph nodes were included in the study. Patients were subjected to clinical examination according to a specially designed proforma and the TNM staging was done. If more than one enlarged nodes were present, then the node with the largest diameter was chosen for further Doppler ultrasonographic examination followed by fine needle aspiration cytology test of the same node. Results: Correlations of patterns of color Doppler flow signals with cytological diagnosis showed that central type of vascular pattern was statistically significant parameter for benign lymph nodes and peripheral type of vascularity was highly significant parameter for malignant lymphadenopathy. It was found that the cut-off value of resistive index 0.6 was statistically significant in the assessment of metastatic node (P < 0.01 with a sensitivity of 45.5% and specificity of 93.9%. On comparison of the clinical features (TNM staging with Doppler sonographic features, it was found that the characteristic features suggestive of malignant lymph nodes on Doppler sonography such as peripheral blood flow and high resistive index were more consistently and frequently associated with the higher sub-stages of T3 and T4 and N2b and N2c of TNM staging system. Conclusion: Nodal vascularity may be used to differentiate benign from malignant lymphadenopathy. Proper judicious use of non-invasive color Doppler ultrasonographic examination provides an opportunity to eliminate the need for biopsy in reactive nodes and provide treatment in a more precise manner.
Energy Technology Data Exchange (ETDEWEB)
Ott, O.J.; Roedel, C.; Sauer, R.; Grabenbauer, G.G. [Dept. of Radiation Oncology, Univ. of Erlangen (Germany); Gramatzki, M. [Dept. of Hematology and Oncology, Univ. of Erlangen (Germany); Niedobitek, G. [Inst. of Pathology, Univ. of Erlangen (Germany)
2003-10-01
Background: To evaluate retrospectively long-term results and patterns of recurrence in patients with low-grade non-Hodgkin's lymphoma (NHL) Ann Arbor stage I-II and limited stage III. Patients and Methods: 58 patients, who had been treated between 1980 and 1996, were analyzed. Median follow-up period was 8.75 years. 48 patients (83%) presented with follicular lymphoma (stage I: 23 patients, stage II and III: 15 and ten patients, respectively). Median age was 51 years. Irradiation was applied with a median total dose of 40 Gy. 13 patients (22%) additionally received chemotherapy. End points of the investigation were remission rate, overall- and disease-free survival, and patterns of recurrence, as well as the prognostic impact of age, B-symptoms, chemotherapy, irradiation dose, treatment volume, and Ann Arbor stage. Results: 6 weeks after treatment 91% of the patients had complete, 7% partial response. One patient (2%) was classified as progressive disease. Overall survival rate was 86% and 69% at 5 and 10 years, respectively. Corresponding disease-free survival rates were 73% and 63%. Regarding overall survival, multivariate analysis identified age (p = 0.001) as independent prognostic factor. In the subgroup of patients with follicular lymphoma 92% were found in complete, 6% in partial remission, one patient (2%) with progressive disease. Overall survival rates at 5 und 10 years were 87% and 70%, disease-free survival rates 75% and 64%, respectively. Out-of-field recurrence rate for all 58 patients was 34% and the proportion of relapses at nodal or lymphatic sites outside the treated areas in relation to all registered recurrences was 77%. Conclusions: Our results maintain external radiotherapy as a curative concept in the treatment of limited stage low-grade lymphoma, especially in younger patients. Patterns of recurrence would favor total nodal irradiation (TNI) as an appropriate approach for these patients. (orig.)
6. Myelin organization in the nodal, paranodal, and juxtaparanodal regions revealed by scanning x-ray microdiffraction.
Science.gov (United States)
Inouye, Hideyo; Liu, Jiliang; Makowski, Lee; Palmisano, Marilena; Burghammer, Manfred; Riekel, Christian; Kirschner, Daniel A
2014-01-01
X-ray diffraction has provided extensive information about the arrangement of lipids and proteins in multilamellar myelin. This information has been limited to the abundant inter-nodal regions of the sheath because these regions dominate the scattering when x-ray beams of 100 µm diameter or more are used. Here, we used a 1 µm beam, raster-scanned across a single nerve fiber, to obtain detailed information about the molecular architecture in the nodal, paranodal, and juxtaparanodal regions. Orientation of the lamellar membrane stacks and membrane periodicity varied spatially. In the juxtaparanode-internode, 198-202 Å-period membrane arrays oriented normal to the nerve fiber axis predominated, whereas in the paranode-node, 205-208 Å-period arrays oriented along the fiber direction predominated. In parts of the sheath distal to the node, multiple sets of lamellar reflections were observed at angles to one another, suggesting that the myelin multilayers are deformed at the Schmidt-Lanterman incisures. The calculated electron density of myelin in the different regions exhibited membrane bilayer profiles with varied electron densities at the polar head groups, likely due to different amounts of major myelin proteins (P0 glycoprotein and myelin basic protein). Scattering from the center of the nerve fibers, where the x-rays are incident en face (perpendicular) to the membrane planes, provided information about the lateral distribution of protein. By underscoring the heterogeneity of membrane packing, microdiffraction analysis suggests a powerful new strategy for understanding the underlying molecular foundation of a broad spectrum of myelinopathies dependent on local specializations of myelin structure in both the PNS and CNS.
7. TAQUICARDIA POR REENTRADA DEL NODO AURÍCULO-VENTRICULAR / Atrioventricular nodal reentrant tachycardia
Directory of Open Access Journals (Sweden)
Jéssica Mirella Mercedes
2013-01-01
Full Text Available Resumen La taquicardia por reentrada del nodo aurículo–ventricular representa una parte significativa de las taquiarritmias que los médicos asisten en los servicios de urgencias. Constituye la taquicardia paroxística más frecuente, y es característico que se presente sobre todo en mujeres entre la cuarta y la quinta década de la vida. El diagnóstico puede hacerse con alta fiabilidad mediante el electrocardiograma de superficie y algunos casos complejos o dudosos, mediante los estudios electrofisiológicos. Su tratamiento debe ser dirigido hacia la curación definitiva mediante la técnica de ablación endocavitaria, pero de acuerdo a su disponibilidad o las preferencias del paciente se puede indicar tratamiento farmacológico. En este artículo se resumen las técnicas diagnósticas, los tipos de taquicardia por reentrada intranodal y los principales aspectos del tratamiento. / Abstract Atrioventricular nodal reentrant tachycardia represents a significant part of tachyarrhythmias seen by attending physicians in emergency departments. It is the most common paroxysmal tachycardia, and it occurs primarily in women between their fourth and fifth decades of life. Diagnosis can be made with high reliability by surface electrocardiogram and complex or borderline cases by electrophysiological studies. Its treatment should be aimed towards definitive healing by endocardial ablation technique, but depending on availability or patient preferences drug treatment may be indicated. This article summarizes the diagnostic techniques, types of atrioventricular nodal reentrant tachycardia and major aspects of treatment.
8. Quantum simulation of exotic PT -invariant topological nodal loop bands with ultracold atoms in an optical lattice
Science.gov (United States)
Zhang, Dan-Wei; Zhao, Y. X.; Liu, Rui-Bin; Xue, Zheng-Yuan; Zhu, Shi-Liang; Wang, Z. D.
2016-04-01
Since the well-known PT symmetry has its fundamental significance and implication in physics, where PT denotes a joint operation of space inversion P and time reversal T , it is important and intriguing to explore exotic PT -invariant topological metals and to physically realize them. Here we develop a theory for a different type of topological metals that are described by a two-band model of PT -invariant topological nodal loop states in a three-dimensional Brillouin zone, with the topological stability being revealed through the PT -symmetry-protected nontrivial Z2 topological charge even in the absence of both P and T symmetries. Moreover, the gapless boundary modes are demonstrated to originate from the nontrivial topological charge of the bulk nodal loop. Based on these exact results, we propose an experimental scheme to realize and to detect tunable PT -invariant topological nodal loop states with ultracold atoms in an optical lattice, in which atoms with two hyperfine spin states are loaded in a spin-dependent three-dimensional optical lattice and two pairs of Raman lasers are used to create out-of-plane spin-flip hopping with site-dependent phase. It is shown that such a realistic cold-atom setup can yield topological nodal loop states, having a tunable band-touching ring with the twofold degeneracy in the bulk spectrum and nontrivial surface states. The nodal loop states are actually protected by the combined PT symmetry and are characterized by a Z2-type invariant (or topological charge), i.e., a quantized Berry phase. Remarkably, we demonstrate with numerical simulations that (i) the characteristic nodal ring can be detected by measuring the atomic transfer fractions in a Bloch-Zener oscillation; (ii) the topological invariant may be measured based on the time-of-flight imaging; and (iii) the surface states may be probed through Bragg spectroscopy. The present proposal for realizing topological nodal loop states in cold-atom systems may provide a unique
9. Coordinating International Response to Emergencies
International Nuclear Information System (INIS)
Pandemic disease, natural disasters and terrorism can affect thousands of people in a relatively short period of time anywhere in the world. Our recent international experience with hurricanes, earthquakes, tsunamis and infectious diseases (AIDS, TB and highly pathogenic avian influenza) show us that we must respond with a coordinated approach or we will fail the very people we intend to help. Nations from around the world are often eager to send assistance to the site of a disaster, but coordinating the incoming aid is more often flawed and imprecise than it must be in order to save lives and mitigate suffering. How can any one country, suffering from a horrendous calamity coordinate the incoming aid from around the world? Can any one agency hope to coordinate the myriad nation's response let alone that of the hundreds of non-governmental organizations? Currently, the answer is sadly, no. The purpose of this presentation is not to recommend one over the many international bodies which claim to oversee humanitarian assistance; the purpose of this presentation is to discuss the elements of only one aspect of the overall response effort: public health and medical response coordination. Public health response is of course different than a purely medical response. Traditionally, in a natural disaster, immediate public health concerns center around water, sewerage/waste disposal, potential for disease outbreaks, etc, whereas medical response concentrates on triage, saving those who can be saved, patching up the injured, and to a lesser extent, primary care to the survivors. In order to avoid political controversy, this presentation will use the example of Hurricane Iniki in Hawaii, September 1992, to illustrate key concepts. The State of Hawaii is no stranger to natural disasters. Their emergency response mechanisms are well honed, exercised and quite capable. However, the local community leaders on Kauai Island went thru each of the following phases before they
10. Neutron transport in hexagonal reactor cores modeled by trigonal-geometry diffusion and simplified P{sub 3} nodal methods
Energy Technology Data Exchange (ETDEWEB)
Duerigen, Susan
2013-05-15
The superior advantage of a nodal method for reactor cores with hexagonal fuel assemblies discretized as cells consisting of equilateral triangles is its mesh refinement capability. In this thesis, a diffusion and a simplified P{sub 3} (or SP{sub 3}) neutron transport nodal method are developed based on trigonal geometry. Both models are implemented in the reactor dynamics code DYN3D. As yet, no other well-established nodal core analysis code comprises an SP{sub 3} transport theory model based on trigonal meshes. The development of two methods based on different neutron transport approximations but using identical underlying spatial trigonal discretization allows a profound comparative analysis of both methods with regard to their mathematical derivations, nodal expansion approaches, solution procedures, and their physical performance. The developed nodal approaches can be regarded as a hybrid NEM/AFEN form. They are based on the transverse-integration procedure, which renders them computationally efficient, and they use a combination of polynomial and exponential functions to represent the neutron flux moments of the SP{sub 3} and diffusion equations, which guarantees high accuracy. The SP{sub 3} equations are derived in within-group form thus being of diffusion type. On this basis, the conventional diffusion solver structure can be retained also for the solution of the SP{sub 3} transport problem. The verification analysis provides proof of the methodological reliability of both trigonal DYN3D models. By means of diverse hexagonal academic benchmark and realistic detailed-geometry full-transport-theory problems, the superiority of the SP{sub 3} transport over the diffusion model is demonstrated in cases with pronounced anisotropy effects, which is, e.g., highly relevant to the modeling of fuel assemblies comprising absorber material.
11. Neutron transport in hexagonal reactor cores modeled by trigonal-geometry diffusion and simplified P3 nodal methods
International Nuclear Information System (INIS)
The superior advantage of a nodal method for reactor cores with hexagonal fuel assemblies discretized as cells consisting of equilateral triangles is its mesh refinement capability. In this thesis, a diffusion and a simplified P3 (or SP3) neutron transport nodal method are developed based on trigonal geometry. Both models are implemented in the reactor dynamics code DYN3D. As yet, no other well-established nodal core analysis code comprises an SP3 transport theory model based on trigonal meshes. The development of two methods based on different neutron transport approximations but using identical underlying spatial trigonal discretization allows a profound comparative analysis of both methods with regard to their mathematical derivations, nodal expansion approaches, solution procedures, and their physical performance. The developed nodal approaches can be regarded as a hybrid NEM/AFEN form. They are based on the transverse-integration procedure, which renders them computationally efficient, and they use a combination of polynomial and exponential functions to represent the neutron flux moments of the SP3 and diffusion equations, which guarantees high accuracy. The SP3 equations are derived in within-group form thus being of diffusion type. On this basis, the conventional diffusion solver structure can be retained also for the solution of the SP3 transport problem. The verification analysis provides proof of the methodological reliability of both trigonal DYN3D models. By means of diverse hexagonal academic benchmark and realistic detailed-geometry full-transport-theory problems, the superiority of the SP3 transport over the diffusion model is demonstrated in cases with pronounced anisotropy effects, which is, e.g., highly relevant to the modeling of fuel assemblies comprising absorber material.
12. Impact of FDG-PET/CT Imaging on Nodal Staging for Head-And-Neck Squamous Cell Carcinoma
International Nuclear Information System (INIS)
Purpose: To evaluate the impact of 18F-fluorodeoxyglucose positron emission tomography/computed tomography (FDG-PET/CT) imaging on nodal staging for head-and-neck squamous cell carcinoma (SCC). Methods and Materials: The study population consisted of 23 patients with head-and-neck SCC who were evaluated with FDG-PET/CT and went on to neck dissection. Two observers consensually determined the lesion size and maximum standardized uptake value (SUVmax) and compared the results with pathologic findings on nodal-level involvement. Two different observers (A and B) independently performed three protocols for clinical nodal staging. Methods 1, 2, and 3 were based on conventional modalities, additional visual information from FDG-PET/CT images, and FDG-PET/CT imaging alone with SUV data, respectively. Results: All primary tumors were visualized with FDG-PET/CT. Pathologically, 19 positive and 93 negative nodal levels were identified. The SUVmax overlapped in negative and positive nodes max cutoff values were 1.9, 2.5, and 3.0 for lymph nodes 15 mm, respectively. These cutoff values yielded 79% sensitivity and 99% specificity for nodal-level staging. For Observer A, the sensitivity and specificity in Methods 1, 2, and 3 were 68% and 94%, 68% and 99%, and 84% and 99%, respectively, and Method 3 yielded significantly higher accuracy than Method 1 (p = 0.0269). For Observer B, Method 3 yielded the highest sensitivity (84%) and specificity (99%); however, the difference among the three protocols was not statistically significant. Conclusion: Imaging with FDG-PET/CT with size-based SUVmax cutoff values is an important modality for radiation therapy planning
13. Absolute angular calibration of a submarine km3 neutrino telescope
International Nuclear Information System (INIS)
A requirement for neutrino telescope is the ability to resolve point sources of neutrinos. In order to understand its resolving power a way to perform absolute angular calibration with muons is required. Muons produced by cosmic rays in the atmosphere offer an abundant calibration source. By covering a surface vessel with 200 modules of 5 m2 plastic scintillator a surface air shower array can be set up. Running this array in coincidence with a deep-sea km3 size neutrino detector, where the coincidence is defined by the absolute clock timing stamp for each event, would allow absolute angular calibration to be performed. Monte Carlo results simulating the absolute angular calibration of the km3 size neutrino detector will be presented. Future work and direction will be discussed.
14. A proposal to measure absolute environmental sustainability in lifecycle assessment
DEFF Research Database (Denmark)
Bjørn, Anders; Margni, Manuele; Roy, Pierre-Olivier;
2016-01-01
in supporting decisions aimed at simultaneously reducing environmental impacts efficiently and maintaining or achieving environmental sustainability. We have demonstrated that LCA indicators can be modified from being relative to being absolute indicators of environmental sustainability. Further research should...
15. Absolute value preconditioning for symmetric indefinite linear systems
CERN Document Server
Vecharynski, Eugene
2011-01-01
We introduce a novel strategy for constructing symmetric positive definite (SPD) preconditioners for linear systems with symmetric indefinite coefficient matrices. The strategy is motivated by the observation that the preconditioned minimal residual method with the inverse of the absolute value of the coefficient matrix as a preconditioner converges to the exact solution of the system in at most two steps. Neither the exact absolute value of the coefficient matrix, nor its exact inverse are computationally feasible to construct in general. However, as the proof of concept, we provide two practical examples of SPD preconditioners, which are based on the suggested approach, called absolute value preconditioning. The first example is for strictly (block) diagonally dominant coefficient matrices, where we propose using the inverse to the absolute value of the (block) diagonal as the preconditioner. Our second example is less intuitive. We consider a model problem with a shifted discrete negative Laplacian, and su...
16. Absolute Value Boundedness, Operator Decomposition, and Stochastic Media and Equations
Science.gov (United States)
1973-01-01
The research accomplished during this period is reported. Published abstracts and technical reports are listed. Articles presented include: boundedness of absolute values of generalized Fourier coefficients, propagation in stochastic media, and stationary conditions for stochastic differential equations.
17. Preparation of an oakmoss absolute with reduced allergenic potential.
Science.gov (United States)
Ehret, C; Maupetit, P; Petrzilka, M; Klecak, G
1992-06-01
Synopsis Oakmoss absolute, an extract of the lichen Evernia prunastri, is known to cause allergenic skin reactions due to the presence of certain aromatic aldehydes such as atranorin, chloratranorin, ethyl hematommate and ethyl chlorohematommate. In this paper it is shown that treatment of Oakmoss absolute with amino acids such as lysine and/or leucine, lowers considerably the content of these allergenic constituents including atranol and chloratranol. The resulting Oakmoss absolute, which exhibits an excellent olfactive quality, was tested extensively in comparative studies on guinea pigs and on man. The results of the Guinea Pig Maximization Test (GPMT) and Human Repeated Insult Patch Test (HRIPT) indicate that, in comparison with the commercial test sample, the allergenicity of this new quality of Oakmoss absolute was considerably reduced, and consequently better skin tolerance of this fragrance for man was achieved. PMID:19272096
DEFF Research Database (Denmark)
Hankin, Chris; Nielson, Flemming; Nielson, Hanne Riis;
2008-01-01
We show how to extend a coordination language with support for aspect oriented programming. The main challenge is how to properly deal with the trapping of actions before the actual data have been bound to the formal parameters. This necessitates dealing with open joinpoints – which is more...
19. Block coordination copolymers
Energy Technology Data Exchange (ETDEWEB)
Koh, Kyoung Moo; Wong-Foy, Antek G; Matzger, Adam J; Benin, Annabelle I; Willis, Richard R
2014-11-11
The present invention provides compositions of crystalline coordination copolymers wherein multiple organic molecules are assembled to produce porous framework materials with layered or core-shell structures. These materials are synthesized by sequential growth techniques such as the seed growth technique. In addition, the invention provides a simple procedure for controlling functionality.
DEFF Research Database (Denmark)
Terepeta, Michal Tomasz; Nielson, Hanne Riis; Nielson, Flemming
2012-01-01
Aspect-oriented programming is a programming paradigm that is often praised for the ability to create modular software and separate cross-cutting concerns. Recently aspects have been also considered in the context of coordination languages, offering similar advantages. However, introducing aspects...
1. Block coordination copolymers
Science.gov (United States)
Koh, Kyoung Moo; Wong-Foy, Antek G; Matzger, Adam J; Benin, Annabelle I; Willis, Richard R
2012-11-13
The present invention provides compositions of crystalline coordination copolymers wherein multiple organic molecules are assembled to produce porous framework materials with layered or core-shell structures. These materials are synthesized by sequential growth techniques such as the seed growth technique. In addition, the invention provides a simple procedure for controlling functionality.
2. Absolute Free Energies for Biomolecules in Implicit or Explicit Solvent
Science.gov (United States)
Berryman, Joshua T.; Schilling, Tanja
Methods for absolute free energy calculation by alchemical transformation of a quantitative model to an analytically tractable one are discussed. These absolute free energy methods are placed in the context of other methods, and an attempt is made to describe the best practice for such calculations given the current state of the art. Calculations of the equilibria between the four free energy basins of the dialanine molecule and the two right- and left-twisted basins of DNA are discussed as examples.
3. Establishment of Absolute Gravity Datum in CMONOC and Its Application
OpenAIRE
XING Lelin; LI Hui; Li, Jianguo; Zhang, Weimin; HE Zhitang
2016-01-01
The high accuracy absolute gravity datum covered the Chinese mainland area is established by using absolute gravity measurement data of one hundred stations in CMONOC(Crustal Movement Observation Network of China), the accuracy of each station is better than 5.0 μGal/a. The high accuracy gravity datum can be used for relative gravity measurements in adjustment, and the real gravity value can be determined from relative gravity measurement data of adjustment by using the gravity datum to avoid...
4. Absolute Branching Fraction Measurements of Exclusive D^0 Semileptonic Decays
CERN Document Server
Coan, T E; Liu, F; Artuso, M; Boulahouache, C; Blusk, S; Butt, J; Dambasuren, E; Dorjkhaidav, O; Li, J; Menaa, N; Mountain, R; Nandakumar, R; Redjimi, R; Sia, R; Skwarnicki, T; Stone, S; Wang, J C; Zhang, K; Csorna, S E; Bonvicini, G; Cinabro, D; Dubrovin, M; Briere, R A; Chen, G P; Chen, J; Ferguson, T; Tatishvili, G T; Vogel, H; Watkins, M E; Rosner, J L; Adam, N E; Alexander, J P; Berkelman, K; Cassel, D G; Credé, V; Duboscq, J E; Ecklund, K M; Ehrlich, R; Fields, L; Gibbons, L; Gittelman, B; Gray, R; Gray, S W; Hartill, D L; Heltsley, B K; Hertz, D; Hsu, L; Jones, C D; Kandaswamy, J; Kreinick, D L; Kuznetsov, V E; Mahlke-Krüger, H; Meyer, T O; Onyisi, P U E; Patterson, J R; Peterson, D; Pivarski, J; Phillips, E A; Riley, D; Ryd, A; Sadoff, A J; Schwarthoff, H; Shepherd, M R; Stroiney, S; Sun, W M; Urner, D; Wilksen, T; Weinberger, M; Athar, S B; Avery, P; Breva-Newell, L; Patel, R; Potlia, V; Stöck, H; Yelton, J; Rubin, P; Cawlfield, C; Eisenstein, B I; Gollin, G D; Karliner, I; Kim, D; Lowrey, N; Naik, P; Sedlack, C; Selen, M; Williams, J; Wiss, J; Edwards, K W; Besson, D; Pedlar, T K; Cronin-Hennessy, D; Gao, K Y; Gong, D T; Kubota, Y; Klein, T; Lang, B W; Li, S Z; Poling, R; Scott, A W; Smith, A; Dobbs, S; Metreveli, Z V; Seth, K K; Tomaradze, A G; Zweber, P; Ernst, J; Mahmood, A H; Severini, H; Asner, D M; Dytman, S A; Love, W; Mehrabyan, S S; Müller, J A; Savinov, V; Li, Z; López, A; Méndez, H; Ramírez, J; Huang, G S; Miller, D H; Pavlunin, V; Sanghi, B; Shibata, E I; Shipsey, I P J; Adams, G S; Chasse, M; Cravey, M; Cummings, J P; Danko, I; Napolitano, J; He, Q; Muramatsu, H; Park, C S; Park, W; Thorndike, E H
2005-01-01
With the first data sample collected by the CLEO-c detector at the psi(3770) resonance we have studied four exclusive semileptonic decays of the D0 meson. Our results include the first observation and absolute branching fraction measurement for D0 --> rho- e+ nu_e and improved measurements of the absolute branching fractions for D0 decays to K- e+ nu_e, pi- e+ nu_e, and K*- e+ nu_e.
5. DIAGNOSTIC TEST FOR GARCH MODELS BASED ON ABSOLUTE RESIDUAL AUTOCORRELATIONS
Directory of Open Access Journals (Sweden)
Farhat Iqbal
2013-10-01
Full Text Available In this paper the asymptotic distribution of the absolute residual autocorrelations from generalized autoregressive conditional heteroscedastic (GARCH models is derived. The correct asymptotic standard errors for the absolute residual autocorrelations are also obtained and based on these results, a diagnostic test for checking the adequacy of GARCH-type models are developed. Our results do not depend on the existence of higher moments and is therefore robust under heavy-tailed distributions.
6. The Pragmatics of "Unruly" Dative Absolutes in Early Slavic
Directory of Open Access Journals (Sweden)
Daniel E. Collins
2011-08-01
Full Text Available This chapter examines some uses of the dative absolute in Old Church Slavonic and in early recensional Slavonic texts that depart from notions of how Indo-European absolute constructions should behave, either because they have subjects coreferential with the (putative main-clause subjects or because they function as if they were main clauses in their own right. Such "noncanonical" absolutes have generally been written off as mechanistic translations or as mistakes by scribes who did not understand the proper uses of the construction. In reality, the problem is not with literalistic translators or incompetent scribes but with the definition of the construction itself; it is quite possible to redefine the Early Slavic dative absolute in a way that accounts for the supposedly deviant cases. While the absolute is generally dependent semantically on an adjacent unit of discourse, it should not always be regarded as subordinated syntactically. There are good grounds for viewing some absolutes not as dependent clauses but as independent sentences whose collateral character is an issue not of syntax but of the pragmatics of discourse.
7. Method to obtain absolute impurity density profiles combining charge exchange and beam emission spectroscopy without absolute intensity calibrationa)
Science.gov (United States)
Kappatou, A.; Jaspers, R. J. E.; Delabie, E.; Marchuk, O.; Biel, W.; Jakobs, M. A.
2012-10-01
Investigation of impurity transport properties in tokamak plasmas is essential and a diagnostic that can provide information on the impurity content is required. Combining charge exchange recombination spectroscopy (CXRS) and beam emission spectroscopy (BES), absolute radial profiles of impurity densities can be obtained from the CXRS and BES intensities, electron density and CXRS and BES emission rates, without requiring any absolute calibration of the spectra. The technique is demonstrated here with absolute impurity density radial profiles obtained in TEXTOR plasmas, using a high efficiency charge exchange spectrometer with high etendue, that measures the CXRS and BES spectra along the same lines-of-sight, offering an additional advantage for the determination of absolute impurity densities.
8. Method to obtain absolute impurity density profiles combining charge exchange and beam emission spectroscopy without absolute intensity calibration
Energy Technology Data Exchange (ETDEWEB)
Kappatou, A.; Delabie, E. [FOM Institute DIFFER - Dutch Institute for Fundamental Energy Research, Association EURATOM-FOM, 3430 BE Nieuwegein (Netherlands); Jaspers, R. J. E.; Jakobs, M. A. [Science and Technology of Nuclear Fusion, Eindhoven University of Technology, 5600 MB Eindhoven (Netherlands); Marchuk, O.; Biel, W. [Institute for Energy and Climate Research, Forschungszentrum Julich GmbH, Trilateral Euregio Cluster, 52425 Julich (Germany)
2012-10-15
Investigation of impurity transport properties in tokamak plasmas is essential and a diagnostic that can provide information on the impurity content is required. Combining charge exchange recombination spectroscopy (CXRS) and beam emission spectroscopy (BES), absolute radial profiles of impurity densities can be obtained from the CXRS and BES intensities, electron density and CXRS and BES emission rates, without requiring any absolute calibration of the spectra. The technique is demonstrated here with absolute impurity density radial profiles obtained in TEXTOR plasmas, using a high efficiency charge exchange spectrometer with high etendue, that measures the CXRS and BES spectra along the same lines-of-sight, offering an additional advantage for the determination of absolute impurity densities.
9. The dynamic right-to-left translocation of Cerl2 is involved in the regulation and termination of Nodal activity in the mouse node.
Directory of Open Access Journals (Sweden)
José Manuel Inácio
Full Text Available The determination of left-right body asymmetry in mouse embryos depends on the interplay of molecules in a highly sensitive structure, the node. Here, we show that the localization of Cerl2 protein does not correlate to its mRNA expression pattern, from 3-somite stage onwards. Instead, Cerl2 protein displays a nodal flow-dependent dynamic behavior that controls the activity of Nodal in the node, and the transmission of the laterality information to the left lateral plate mesoderm (LPM. Our results indicate that Cerl2 initially localizes and prevents the activation of Nodal genetic circuitry on the right side of the embryo, and later its right-to-left translocation shutdowns Nodal activity in the node. The consequent prolonged Nodal activity in the node by the absence of Cerl2 affects local Nodal expression and prolongs its expression in the LPM. Simultaneous genetic removal of both Nodal node inhibitors, Cerl2 and Lefty1, sustains even longer and bilateral this LPM expression.
10. Role of Ultrasonography of Regional Nodal Basins in Staging Triple-Negative Breast Cancer and Implications For Local-Regional Treatment
International Nuclear Information System (INIS)
Purpose: We sought to determine the rate at which regional nodal ultrasonography would increase the nodal disease stage in patients with triple-negative breast cancer (TNBC) beyond the clinical stage determined by physical examination and mammography alone, and significantly affect the treatments delivered to these patients. Methods and Materials: We retrospectively reviewed the charts of women with stages I to III TNBC who underwent physical examination, mammography, breast and regional nodal ultrasonography with needle biopsy of abnormal nodes, and definitive local-regional treatment at our institution between 2004 and 2011. The stages of these patients' disease with and without ultrasonography of the regional nodal basins were compared using the Pearson χ2 test. Definitive treatments of patients whose nodal disease was upstaged on the basis of ultrasonographic findings were compared to those of patients whose disease stage remained the same. Results: A total of 572 women met the study requirements. In 111 (19.4%) of these patients, regional nodal ultrasonography with needle biopsy resulted in an increase in disease stage from the original stage by physical examination and mammography alone. Significantly higher percentages of patients whose nodal disease was upstaged by ultrasonographic findings compared to that in patients whose disease was not upstaged underwent neoadjuvant systemic therapy (91.9% and 51.2%, respectively; P<.0001), axillary lymph node dissection (99.1% and 34.5%, respectively; P<.0001), and radiation to the regional nodal basins (88.2% and 29.1%, respectively; P<.0001). Conclusions: Regional nodal ultrasonography in TNBC frequently changes the initial clinical stage and plays an important role in treatment planning
11. Role of Ultrasonography of Regional Nodal Basins in Staging Triple-Negative Breast Cancer and Implications For Local-Regional Treatment
Energy Technology Data Exchange (ETDEWEB)
Shaitelman, Simona F., E-mail: sfshaitelman@mdanderson.org [Division of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Tereffe, Welela [Division of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Dogan, Basak E. [Department of Diagnostic Radiology, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Hess, Kenneth R. [Department of Biostatistics, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Caudle, Abigail S. [Department of Surgical Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Valero, Vicente [Department of Breast Medical Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Stauder, Michael C. [Division of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Krishnamurthy, Savitri [Department of Pathology, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Candelaria, Rosalind P. [Department of Diagnostic Radiology, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Strom, Eric A.; Woodward, Wendy A. [Division of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Hunt, Kelly K. [Department of Surgical Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Buchholz, Thomas A. [Division of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Whitman, Gary J. [Department of Diagnostic Radiology, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States)
2015-09-01
Purpose: We sought to determine the rate at which regional nodal ultrasonography would increase the nodal disease stage in patients with triple-negative breast cancer (TNBC) beyond the clinical stage determined by physical examination and mammography alone, and significantly affect the treatments delivered to these patients. Methods and Materials: We retrospectively reviewed the charts of women with stages I to III TNBC who underwent physical examination, mammography, breast and regional nodal ultrasonography with needle biopsy of abnormal nodes, and definitive local-regional treatment at our institution between 2004 and 2011. The stages of these patients' disease with and without ultrasonography of the regional nodal basins were compared using the Pearson χ{sup 2} test. Definitive treatments of patients whose nodal disease was upstaged on the basis of ultrasonographic findings were compared to those of patients whose disease stage remained the same. Results: A total of 572 women met the study requirements. In 111 (19.4%) of these patients, regional nodal ultrasonography with needle biopsy resulted in an increase in disease stage from the original stage by physical examination and mammography alone. Significantly higher percentages of patients whose nodal disease was upstaged by ultrasonographic findings compared to that in patients whose disease was not upstaged underwent neoadjuvant systemic therapy (91.9% and 51.2%, respectively; P<.0001), axillary lymph node dissection (99.1% and 34.5%, respectively; P<.0001), and radiation to the regional nodal basins (88.2% and 29.1%, respectively; P<.0001). Conclusions: Regional nodal ultrasonography in TNBC frequently changes the initial clinical stage and plays an important role in treatment planning.
12. Principles of Coordination Polymerisation
Science.gov (United States)
Kuran, Witold
2001-11-01
The first all-inclusive text covering coordination polymerisation, including important classes of non-hydrocarbon monomers. Charting the achievements and progress in the field, in terms of both basic and industrial research, this book offers a unified and complete overview of coordination polymerisation. Provides detailed description of the historical development of the subject Presents a unified view of catalysis, mechanisms, structures and utility Encourages learning through a step-by-step progression from basic to in-depth text Features end-of-chapter exercises to reinforce understanding Offers a full bibliography and comprehensive literature review Requisite reading for research students studying introductory and advanced courses in; polymer science, catalysis and polymerisation catalysis, and valuable reference for researchers and technicians in industry.
13. Comparative analysis of nodalization effects and their influence on the results of ATHLET calculations of VVER-1000 coolant transient benchmark phase 1
International Nuclear Information System (INIS)
In this paper, the results of the investigations on the nodalization effects for the ATHLET code are presented and discussed in details on the basis of experimental data for the VVER-1000 Coolant Transient Benchmark with different operating modes of four main coolant pumps. ATHLET calculations with different nodalization and their impact was analyzed. The work studied the influence of annular outlet nodalization on calculation of coolant temperature. By comparing the test data versus calculated by ATHLET we showed a good agreement between the experimental data and simulation results for analyzed parameters.
OpenAIRE
1990-01-01
We show that when relevant market information such as price is difficult to communicate, advertising plays a key role in bringing about optimal coordination of purchase behavior: an efficient firm uses advertising expenditures in place of price to inform sophisticated consumers that it offers a better deal. This provides a theoretical explanation for Benham's (1972) empirical association of the ability to advertise with lower prices and larger scale. We find that advertising improves welfare ...
15. Communication and interference coordination
OpenAIRE
Blasco-Serrano, Ricardo; Thobaben, Ragnar; Skoglund, Mikael
2014-01-01
We study the problem of controlling the interference created to an external observer by a communication processes. We model the interference in terms of its type (empirical distribution), and we analyze the consequences of placing constraints on the admissible type. Considering a single interfering link, we characterize the communication-interference capacity region. Then, we look at a scenario where the interference is jointly created by two users allowed to coordinate their actions prior to...
16. International Monetary Policy Coordination
OpenAIRE
Carlberg, Michael
2005-01-01
This paper studies the international coordination of monetary policies in the world economy. It carefully discusses the process of policy competition and the structure of policy cooperation. As to policy competition, the focus is on monetary competition between Europe and America. Similarly, as to policy cooperation, the focus is on monetary cooperation between Europe and America. The spillover effects of monetary policy are negative. The policy targets are price stability and full employment.
17. Improved local control without elective nodal radiotherapy in patients with unresectable NSCLC treated by 3D-CRT
Institute of Scientific and Technical Information of China (English)
YANG Kunyu; CAO Fengjun; WANG Jianhua; LIU Li; ZHANG Tao; WU Gang
2007-01-01
To investigate the influence of prophylactic elective nodal irradiation on the therapeutic results of definitive radiotherapy for patients with stage IliA or stage IIIB unresectable non-small-cell lung cancer,55 patients with clinically inoperable advanced non-small-cell lung cancer were studied.After four cycles of induction chemotherapy,the patients were divided into two groups at random.In one group,the elective nodal irradiation was included in clinical tumor volume(CTV)of definitive radiotherapy(ENI group);and in the other group,elective nodal irradiation was not included in CTV(non-ENI group).For the patients in the ENI group,the mean prescription dose for gross tumor volumes was 58.4 Gy,while for the patients in the non-ENI group,it was 65.8 Gy(P＜0.05).The responsive rates were 45.8% and 74.0%(P＜0.05),and the rate of the elective nodal failure (ENF)was 4.2% and 11.1%,respectively.Kaplan-Meier analysis showed that the mean local-progression-free survival time was 11.0 and 15.0 months,and one-year local-failure rates were 51.9% and 24.5%(P＜0.05).The median overall survival time was 13.0 and 15.0 months,respectively (P=0.084).The one-year survival rates were 55.7% and 72.5%,and two-year survival rates were 0% and 19.9%.There was no significant difference in the occurrences of radiation-associated complications between the two groups.Our results showed that omitting elective nodal irradiation did not result in a high incidence of elective nodal failure.On the contrary,it decreased local failure by increasing prescription doses to the primary diseases and lymphadenopaphy,and thereby it may further prolong the patients' survival.
18. Global coordination: weighted voting
Directory of Open Access Journals (Sweden)
Jan-Erik Lane
2014-03-01
Full Text Available In order to halt the depletion of global ecological capital, a number of different kinds of meetings between Governments of countries in the world has been scheduled. The need for global coordination of environmental policies has become ever more obvious, supported by more and more evidence of the running down of ecological capital. But there are no formal or binding arrangements in sight, as global environmental coordination suffers from high transaction costs (qualitative voting. The CO2 equivalent emissions, resulting in global warming, are driven by the unstoppable economic expansion in the global market economy, employing mainly fossil fuel generated energy, although at the same time lifting sharply the GDP per capita of several emerging countries. Only global environmental coordination on the successful model of the World Band and the IMF (quantitative voting can stem the rising emissions numbers and stop further environmental degradation. However, the system of weighted voting in the WB and the IMF must be reformed by reducing the excessive voting power disparities, for instance by reducing all member country votes by the cube root expression.
19. Improving Project Manufacturing Coordination
Directory of Open Access Journals (Sweden)
Korpivaara Ville
2014-09-01
Full Text Available The objective of this research is to develop firms’ project manufacturing coordination. The development will be made by centralizing the manufacturing information flows in one system. To be able to centralize information, a deep user need assessment is required. After user needs have been identified, the existing system will be developed to match these needs. The theoretical background is achieved through exploring the literature of project manufacturing, development project success factors and different frameworks and tools for development project execution. The focus of this research is rather in customer need assessment than in system’s technical expertise. To ensure the deep understanding of customer needs this study is executed by action research method. As a result of this research the information system for project manufacturing coordination was developed to respond revealed needs of the stakeholders. The new system improves the quality of the manufacturing information, eliminates waste in manufacturing coordination processes and offers a better visibility to the project manufacturing. Hence it provides a solid base for the further development of project manufacturing.
20. Nodal colloid goiter: clinical and morphological criteria of thyroid autonomy and progressive growth
Directory of Open Access Journals (Sweden)
S S Antonova
2006-03-01
Full Text Available Goal. To work up clinical and morphological criteria of thyroid authonomy and progressive growth in nodal colloid goiter (NCG. Methods. A group of patients with nodal euthyroid goiter (NEG (40 patients and a group of patients with nodular toxic goiter (NTG (40 patients were formed to compare clinical and morphological criteria of NCG growth to/with development of functional autonomy (FA. All patients were conducted research including physical examination, thyroid palpation, ultrasound, blood level of TSH and T4, scintigraphy, aspiration (needle biopsy, immunocytological and immunohistological reactions and statistics. In the study the method of indirect immunoperoxidase reaction with monoclonal rat/mouse antigens to Ki-67, TSH, galectin-3, Apo-test (“Dako Corporation”, “Novocastra Laboratories Ltd.” was used. Results. 1. In NEG expression of cell proliferation marker Ki-67 for certain rises pro rata to increase of proliferation degree, and in NTG grows according to FA development. 2. Apoptosis expression in NEG decreases according to degree of thyrocytes in a nodule, but in NTG falls pro rata to accumulation of thyroid FA. 3. Positive reaction for TSH in NEG tissue was found in 100%, whereas negative reaction for this receptor in NTG tissue was observed in 81% of all cases. 4. Galectin-3 was expressed in focuses of severe dysplasia of thyroid nodes tissue comparable to galectin-3 expression in the tissue of high-grade differentiated adenocarcinomas. Summary/conclusion. 1. Severe and moderate expression of Ki-67 and mild or negative immunomorphological reaction for Apo-test allows to refer such kinds of nodules to fast-growing/rapid-growing ones. 2. Reliable negative expression TSH receptor in the tissue of NCG is evidence of FA development and is an indication for a treatment of radioactive iodine or for an operation. 3. Galectin-3 probably is an early marker of malignant transformation in thyroid tissue. 4. Having conducted complex
1. Absolute Calibration of the Radio Astronomy Flux Density Scale at 22 to 43 GHz Using Planck
Science.gov (United States)
Partridge, B.; López-Caniego, M.; Perley, R. A.; Stevens, J.; Butler, B. J.; Rocha, G.; Walter, B.; Zacchei, A.
2016-04-01
The Planck mission detected thousands of extragalactic radio sources at frequencies from 28 to 857 GHz. Planck's calibration is absolute (in the sense that it is based on the satellite’s annual motion around the Sun and the temperature of the cosmic microwave background), and its beams are well characterized at sub-percent levels. Thus, Planck's flux density measurements of compact sources are absolute in the same sense. We have made coordinated Very Large Array (VLA) and Australia Telescope Compact Array (ATCA) observations of 65 strong, unresolved Planck sources in order to transfer Planck's calibration to ground-based instruments at 22, 28, and 43 GHz. The results are compared to microwave flux density scales currently based on planetary observations. Despite the scatter introduced by the variability of many of the sources, the flux density scales are determined to 1%–2% accuracy. At 28 GHz, the flux density scale used by the VLA runs 2%–3% ± 1.0% below Planck values with an uncertainty of +/- 1.0%; at 43 GHz, the discrepancy increases to 5%–6% ± 1.4% for both ATCA and the VLA.
2. Absolute Calibration of the Radio Astronomy Flux Density Scale at 22 to 43 GHz Using Planck
CERN Document Server
Partridge, B; Perley, R A; Stevens, J; Butler, B J; Rocha, G; Walter, B; Zacchei, A
2015-01-01
The Planck mission detected thousands of extragalactic radio sources at frequencies from 28 to 857 GHz. Planck's calibration is absolute (in the sense that it is based on the satellite's annual motion around the Sun and the temperature of the cosmic microwave background), and its beams are well characterized at sub-percent levels. Thus Planck's flux density measurements of compact sources are absolute in the same sense. We have made coordinated VLA and ATCA observations of 65 strong, unresolved Planck sources in order to transfer Planck's calibration to ground-based instruments at 22, 28, and 43 GHz. The results are compared to microwave flux density scales currently based on planetary observations. Despite the scatter introduced by the variability of many of the sources, the flux density scales are determined to 1-2% accuracy. At 28 GHz, the flux density scale used by the VLA runs 3.6% +- 1.0% below Planck values; at 43 GHz, the discrepancy increases to 6.2% +- 1.4% for both ATCA and the VLA.
3. Absolute neutrophil values in malignant patients on cytotoxic chemotherapy.
Science.gov (United States)
Madu, A J; Ibegbulam, O G; Ocheni, S; Madu, K A; Aguwa, E N
2011-01-01
A total of eighty patients with various malignancies seen between September 2008 and April 2009 at the University of Nigeria Teaching Hospital (UNTH) Ituku Ozalla, Enugu, Nigeria, had their absolute neutrophil counts, done at Days 0 and 12 of the first cycle of their various chemotherapeutic regimens. They were adult patients who had been diagnosed of various malignancies, consisting of Breast cancer 36 (45%), Non-Hodgkin's lymphoma 8 (10%), Hodgkin's lymphoma 13 (16.25%), Colorectal carcinoma 6 (7.5%), Multiple myeloma 7 (8.75%), Cervical carcinoma 1 (1.25%) and other malignancies 9 (11.25%), Manual counting of absolute neutrophil count was done using Turks solution and improved Neubauer counting chamber and Galen 2000 Olympus microscope. The socio demographic data of the patients were assessed from a questionnaire. There were 27 males (33.75%) and 53 females (66.25%). Their ages ranged from 18 - 80 years with a median of 45 years. The mean absolute neutrophil count of the respondents pre-and post chemotherapy was 3.7 +/- 2.1 x 10(9)/L and 2.5 +/- 1.6 x 10(9)/L respectively. There were significant differences in both the absolute neutrophil count (p=0.00) compared to the pre-chemotherapy values. Chemotherapeutic combinations containing cyclophosphamide and Adriamycin were observed to cause significant reduction in absolute neutrophil.
4. Relative and absolute risk in epidemiology and health physics
International Nuclear Information System (INIS)
The health risk from ionizing radiation commonly is expressed in two forms: (1) the relative risk, which is the percentage increase in natural disease rate and (2) the absolute or attributable risk which represents the difference between the natural rate and the rate associated with the agent in question. Relative risk estimates for ionizing radiation generally are higher than those expressed as the absolute risk. This raises the question of which risk estimator is the most appropriate under different conditions. The absolute risk has generally been used for radiation risk assessment, although mathematical combinations such as the arithmetic or geometric mean of both the absolute and relative risks, have also been used. Combinations of the two risk estimators are not valid because the absolute and relative risk are not independent variables. Both human epidemiologic studies and animal experimental data can be found to illustrate the functional relationship between the natural cancer risk and the risk associated with radiation. This implies that the radiation risk estimate derived from one population may not be appropriate for predictions in another population, unless it is adjusted for the difference in the natural disease incidence between the two populations
5. Symmetric two-coordinate photodiode
Directory of Open Access Journals (Sweden)
Dobrovolskiy Yu. G.
2008-12-01
Full Text Available The two-coordinate photodiode is developed and explored on the longitudinal photoeffect, which allows to get the coordinate descriptions symmetric on the steepness and longitudinal resistance great exactness. It was shown, that the best type of the coordinate description is observed in the case of scanning by the optical probe on the central part of the photosensitive element. The ways of improvement of steepness and linear of its coordinate description were analyzed.
6. Invariant Manifolds and Collective Coordinates
CERN Document Server
Papenbrock, T
2001-01-01
We introduce suitable coordinate systems for interacting many-body systems with invariant manifolds. These are Cartesian in coordinate and momentum space and chosen such that several components are identically zero for motion on the invariant manifold. In this sense these coordinates are collective. We make a connection to Zickendraht's collective coordinates and present certain configurations of few-body systems where rotations and vibrations decouple from single-particle motion. These configurations do not depend on details of the interaction.
7. Communication, leadership and coordination failure
OpenAIRE
Dong, Lu; Montero, Maria; Possajennikov, Alex
2015-01-01
Using experimental methods, this paper investigates the limits of communication and leadership in aiding group coordination in a minimum effort game. Choosing the highest effort is the payoff dominant Nash equilibrium in this game, and communication and leadership are expected to help in coordinating on such an equilibrium. We consider an environment in which the benefits of coordination are low compared to the cost of mis-coordination. In this environment, players converge to the most ineffi...
8. Shifting nodal-plane suppressions in high-order harmonic spectra from diatomic molecules in orthogonally polarized driving fields
CERN Document Server
Das, T
2016-01-01
We analyze the imprint of nodal planes in high-order harmonic spectra from aligned diatomic molecules in intense laser fields whose components exhibit orthogonal polarizations. We show that the typical suppression in the spectra associated to nodal planes is distorted, and that this distortion can be employed to map the electron's angle of return to its parent ion. This investigation is performed semi-analytically at the single-molecule response and single-active orbital level, using the strong-field approximation and the steepest descent method. We show that the velocity form of the dipole operator is superior to the length form in providing information about this distortion. However, both forms introduce artifacts that are absent in the actual momentum-space wavefunction. Furthermore, elliptically polarized fields lead to larger distortions in comparison to two-color orthogonally polarized fields. These features are investigated in detail for $\\mathrm{O}_2$, whose highest occupied molecular orbital provides...
9. Unusual presentation of Warthin variant of Papillary thyroid carcinoma with lymph nodal metastases in a patient of Graves' disease.
Science.gov (United States)
Padma, Subramanyam; Sundaram, Palaniswamy Shanmuga; Arun, B R
2015-01-01
Warthin-like Papillary thyroid carcinoma (WPTC) is a rare variant of papillary carcinoma of thyroid, PTC which derives its name by closely resembling Warthin's tumor of salivary gland. Hallmark histological feature of this variant is papillary folding lined by oncocytic neoplastic cells with clear nuclei and nuclear pseudoinclusions, accompanied by prominent lymphocytic infiltrate in the papillary stalks. It is thought to be one of those differentiated thyroid cancers with favorable prognosis. We report a case of Graves' disease with a cold nodule harboring WPTC with initial presentation of lymph nodal metastases. It is important to identify this peculiar variant of PTC as 5 to 10% of them undergo dedifferentiation and 30% have the lymph nodal metastases and extra thyroidal extension.
10. Right ventricular involvement with acute inferior wall myocardial infarction identifies high risk of developing atrioventricular nodal conduction disturbances
Energy Technology Data Exchange (ETDEWEB)
Braat, S.H.; de Zwaan, C.; Brugada, P.; Coenegracht, J.M.; Wellens, H.J.
1984-06-01
In 67 consecutive patients with inferior wall acute myocardial infarction (AMI), 99m-technetium pyrophosphate scintigraphy was performed 36 to 72 hours after the onset of chest pain to detect right ventricular (RV) involvement. All patients were continuously monitored during at least 3 days to detect rhythm and conduction disturbances. In 29 patients RV involvement was diagnosed by scintigraphy. None of these 29 patients showed clinical signs of right-sided heart failure. Fourteen of the 19 patients showing atrioventricular (AV) nodal condution disturbances in the setting of inferior AMI also had RV involvement. Therefore, the incidence of high-degree AV nodal block in patients with RV involvement (14 of 29 patients) was 48% compared to only 13% (5 of 38) in patients with inferior AMI without RV involvement.
11. Modeling TRIGA reactor pulses using the STAR 3D nodal kinetics and WIMS-D4 codes
International Nuclear Information System (INIS)
A detailed three-dimensional (3D) time-dependent STAR nodal kinetics model coupled to a one-dimensional (1D) thermal-hydraulics WIGL model has been developed to describe and benchmark the peak power and pulse behavior of the Penn State University (PSU) Breazeale TRIGA reactor. Different core loading patterns were used for several TRIGA pulse tests with different reactivity insertion worths (1.5 dollar, 2.0 dollar, 2.5 dollar). The STAR nodal kinetics code and TRIGA model adequately simulates TRIGA pulses when group constants are generated from physics codes (i.e., WIMS-D4) that can accurately model the TRIGA uranium-zirconium-hydride fuel
12. Simple unbiased estimation of absolute free energies for biomolecules
CERN Document Server
Ytreberg, F M
2005-01-01
One reason that free energy difference calculations are notoriously difficult in molecular systems is due to insufficient conformational overlap, or similarity, between the two states or systems of interest. The degree of overlap is irrelevant, however, if the absolute free energy of each state can be computed. We present a method for calculating the absolute free energy that employs a simple construction of an exactly computable reference system which possesses high overlap with the state of interest. The approach requires only a physical ensemble of conformations generated via simulation, and an auxiliary calculation of approximately equal CPU cost. Moreover, the calculations can converge to the correct free energy value even when the physical ensemble is incomplete or improperly distributed. We use the approach to correctly predict free energies for test systems where the absolute values can be calculated exactly, and also to predict the conformational equilibrium for leucine dipeptide in GBSA implicit sol...
13. The mixed Littlewood conjecture for pseudo-absolute values
CERN Document Server
Harrap, Stephen
2010-01-01
In this paper we prove the mixed Littlewood conjecture for a p-adic absolute value and any pseudo-absolute value with bounded ratios. More precisely we show that if p is a prime and D is a pseudo-absolute value sequence with elements divisible by finitely many primes not equal to p, and if the terms of D grow more slowly than the exponential of a polynomial then the infimum over natural numbers n of the quantity n.|n|_p.|n|_D.||nx|| equals 0 for all real x. Our proof relies on two deep results, a measure rigidity theorem due to Lindenstrauss and lower bounds for linear forms in logarithms due to Baker and Wustholz. We also deduce the answer to the related metric question of how fast the infimum above tends to zero, for almost every x.
14. System and method for calibrating a rotary absolute position sensor
Science.gov (United States)
Davis, Donald R. (Inventor); Permenter, Frank Noble (Inventor); Radford, Nicolaus A (Inventor)
2012-01-01
A system includes a rotary device, a rotary absolute position (RAP) sensor generating encoded pairs of voltage signals describing positional data of the rotary device, a host machine, and an algorithm. The algorithm calculates calibration parameters usable to determine an absolute position of the rotary device using the encoded pairs, and is adapted for linearly-mapping an ellipse defined by the encoded pairs to thereby calculate the calibration parameters. A method of calibrating the RAP sensor includes measuring the rotary position as encoded pairs of voltage signals, linearly-mapping an ellipse defined by the encoded pairs to thereby calculate the calibration parameters, and calculating an absolute position of the rotary device using the calibration parameters. The calibration parameters include a positive definite matrix (A) and a center point (q) of the ellipse. The voltage signals may include an encoded sine and cosine of a rotary angle of the rotary device.
15. An algorithm for estimating Absolute Salinity in the global ocean
Directory of Open Access Journals (Sweden)
T. J. McDougall
2009-02-01
Full Text Available To date, density and other thermodynamic properties of seawater have been calculated from Practical Salinity, S P. It is more accurate however to use Absolute Salinity, S A (the mass fraction of dissolved material in seawater. Absolute Salinity S A can be expressed in terms of Practical Salinity S P as
S A=(35.165 04 g kg-1/35S PS A(φ, λ, p
where δ S A is the Absolute Salinity Anomaly as a function of longitude φ, latitude λ and pressure. When a seawater sample has standard composition (i.e. the ratios of the constituents of sea salt are the same as those of surface water of the North Atlantic, the Absolute Salinity Anomaly is zero. When seawater is not of standard composition, the Absolute Salinity Anomaly needs to be estimated; this anomaly is as large as 0.025 g kg−1 in the northernmost North Pacific. Here we provide an algorithm for estimating Absolute Salinity Anomaly for any location (φ, λ, p in the world ocean.
To develop this algorithm we use the Absolute Salinity Anomaly that is found by comparing the density calculated from Practical Salinity to the density measured in the laboratory. These estimates of Absolute Salinity Anomaly however are limited to the number of available observations (namely 811. To expand our data set we take advantage of approximate relationships between Absolute Salinity Anomaly and silicate concentrations (which are available globally. We approximate the laboratory-determined values of δ S A of the 811 seawater samples as a series of simple functions of the silicate concentration of the seawater sample and latitude; one function for each ocean basin. We use these basin-specific correlations and a digital atlas of silicate in the world ocean to deduce the Absolute Salinity
16. Modeling Students' Units Coordinating Activity
OpenAIRE
Boyce, Steven James
2014-01-01
Primarily via constructivist teaching experiment methodology, units coordination (Steffe, 1992) has emerged as a useful construct for modeling students' psychological constructions pertaining to several mathematical domains, including counting sequences, whole number multiplicative conceptions, and fractions schemes. I describe how consideration of units coordination as a Piagetian (1970b) structure is useful for modeling units coordination across contexts. In this study, I extend teaching ...
17. Neural sensitivity to absolute and relative anticipated reward in adolescents.
Science.gov (United States)
Vaidya, Jatin G; Knutson, Brian; O'Leary, Daniel S; Block, Robert I; Magnotta, Vincent
2013-01-01
Adolescence is associated with a dramatic increase in risky and impulsive behaviors that have been attributed to developmental differences in neural processing of rewards. In the present study, we sought to identify age differences in anticipation of absolute and relative rewards. To do so, we modified a commonly used monetary incentive delay (MID) task in order to examine brain activity to relative anticipated reward value (neural sensitivity to the value of a reward as a function of other available rewards). This design also made it possible to examine developmental differences in brain activation to absolute anticipated reward magnitude (the degree to which neural activity increases with increasing reward magnitude). While undergoing fMRI, 18 adolescents and 18 adult participants were presented with cues associated with different reward magnitudes. After the cue, participants responded to a target to win money on that trial. Presentation of cues was blocked such that two reward cues associated with $.20,$1.00, or $5.00 were in play on a given block. Thus, the relative value of the$1.00 reward varied depending on whether it was paired with a smaller or larger reward. Reflecting age differences in neural responses to relative anticipated reward (i.e., reference dependent processing), adults, but not adolescents, demonstrated greater activity to a $1 reward when it was the larger of the two available rewards. Adults also demonstrated a more linear increase in ventral striatal activity as a function of increasing absolute reward magnitude compared to adolescents. Additionally, reduced ventral striatal sensitivity to absolute anticipated reward (i.e., the difference in activity to medium versus small rewards) correlated with higher levels of trait Impulsivity. Thus, ventral striatal activity in anticipation of absolute and relative rewards develops with age. Absolute reward processing is also linked to individual differences in Impulsivity. PMID:23544046 18. Neural sensitivity to absolute and relative anticipated reward in adolescents. Directory of Open Access Journals (Sweden) Jatin G Vaidya Full Text Available Adolescence is associated with a dramatic increase in risky and impulsive behaviors that have been attributed to developmental differences in neural processing of rewards. In the present study, we sought to identify age differences in anticipation of absolute and relative rewards. To do so, we modified a commonly used monetary incentive delay (MID task in order to examine brain activity to relative anticipated reward value (neural sensitivity to the value of a reward as a function of other available rewards. This design also made it possible to examine developmental differences in brain activation to absolute anticipated reward magnitude (the degree to which neural activity increases with increasing reward magnitude. While undergoing fMRI, 18 adolescents and 18 adult participants were presented with cues associated with different reward magnitudes. After the cue, participants responded to a target to win money on that trial. Presentation of cues was blocked such that two reward cues associated with$.20, $1.00, or$5.00 were in play on a given block. Thus, the relative value of the $1.00 reward varied depending on whether it was paired with a smaller or larger reward. Reflecting age differences in neural responses to relative anticipated reward (i.e., reference dependent processing, adults, but not adolescents, demonstrated greater activity to a$1 reward when it was the larger of the two available rewards. Adults also demonstrated a more linear increase in ventral striatal activity as a function of increasing absolute reward magnitude compared to adolescents. Additionally, reduced ventral striatal sensitivity to absolute anticipated reward (i.e., the difference in activity to medium versus small rewards correlated with higher levels of trait Impulsivity. Thus, ventral striatal activity in anticipation of absolute and relative rewards develops with age. Absolute reward processing is also linked to individual differences in Impulsivity.
19. Optimal sharing of quantity risk for a coalition of wind power producers facing nodal prices
KAUST Repository
Bitar, E. Y.
2012-06-01
It is widely accepted that aggregation of geographically diverse wind energy resources offers compelling potential to mitigate wind power variability, as wind speed at different geographic locations tends to decorrelate with increasing spatial separation. In this paper, we explore the extent to which a coalition of wind power producers can exploit the statistical benefits of aggregation to mitigate the risk of quantity shortfall with respect to forward contract offerings for energy. We propose a simple augmentation of the existing two-settlement market system with nodal pricing to permit quantity risk sharing among wind power producers by affording the group a recourse opportunity to utilize improved forecasts of their ensuing wind energy production to collectively modify their forward contracted positions so as to utilize the projected surplus in generation at certain buses to balance the projected shortfall in generation at complementary buses. Working within this framework, we show that the problem of optimally sizing a set of forward contracts for a group of wind power producers reduces to convex programming and derive closed form expressions for the set of optimal recourse policies. We also asses the willingness of individual wind power producers to form a coalition to cooperatively offer contracts for energy. We first show that the expected profit derived from coalitional contract offerings with recourse is greater than that achievable through independent contract offerings. And, using tools from coalitional game theory, we show that the core for our game is non-empty.
20. Impact of Nodal Centrality Measures to Robustness in Software-Defined Networking
Directory of Open Access Journals (Sweden)
Tomas Hegr
2014-01-01
Full Text Available The paper deals with the network robustness from the perspective of nodal centrality measures and its applicability in Software-Defined Networking (SDN. Traditional graph characteristics have been evolving during the last century, and numerous of less-conventional metrics was introduced trying to bring a new view to some particular graph attributes. New control technologies can finally utilize these metrics but simultaneously show new challenges. SDN brings the fine-grained and nearly online view of the underlying network state which allows to implement an advanced routing and forwarding. In such situation, sophisticated algorithms can be applied utilizing pre-computed network measures. Since in recent version of SDN protocol OpenFlow (OF has been revived an idea of the fast link failover, the authors in this paper introduce a novel metric, Quality of Alternative Paths centrality (QAP. The QAP value quantifies node surroundings and can be with an advantage utilized in algorithms to indicate more robust paths. The centrality is evaluated using the node-failure simulation at different network topologies in combination with the Quality of Backup centrality measure.
1. Uncompacted Myelin Lamellae and Nodal Ion Channel Disruption in POEMS Syndrome.
Science.gov (United States)
Hashimoto, Rina; Koike, Haruki; Takahashi, Mie; Ohyama, Ken; Kawagashira, Yuichi; Iijima, Masahiro; Sobue, Gen
2015-12-01
To elucidate the significance of uncompacted myelin lamellae (UML) and ion channel disruption at the nodes of Ranvier in the polyneuropathy, organomegaly, endocrinopathy, monoclonal gammopathy, and skin changes (POEMS) syndrome, we evaluated sural nerve biopsy specimens from 33 patients with POEMS syndrome and from 7 control patients. Uncompacted myelin lamellae distribution was assessed by electron microscopy and immunofluorescence microscopy. In the POEMS patient biopsies, UML were seen more frequently in small versus large myelinated fibers. Paranodes and Schmidt-Lanterman incisures, where normal physiologic UM is located, were frequently associated with UM. Widening of the nodes of Ranvier (i.e. segmental demyelination) was not associated with UML. There was axonal hollowing with neurofilament condensation at Schmidt-Lanterman incisures with abnormal UML, suggesting axonal damage at those sites in the POEMS patient biopsies. Myelin sheath irregularity was conspicuous in large myelinated fibers and was associated with abnormally widened bizarrely shaped Schmidt-Lanterman incisures. Indirect immunofluorescent studies revealed abnormalities of sodium (pan sodium) and potassium (KCNQ2) channels, even at nonwidened nodes of Ranvier. Thus, UML was not apparently associated with segmental demyelination but seemed to be associated with axonal damage. These observations suggest that nodal ion channel disruption may be associated with functional deficits in POEMS syndrome patient nerves.
2. Landau level quantization and almost flat modes in three-dimensional semimetals with nodal ring spectra
Science.gov (United States)
We investigate Landau level structures of semimetals with nodal ring dispersions. When the magnetic field is applied parallel to the plane in which the ring lies, there exist almost nondispersive Landau levels at the Fermi level (EF = 0) as a function of the momentum along the field direction inside the ring. We show that the Landau levels at each momentum along the field direction can be described by the Hamiltonian for the graphene bilayer with fictitious interlayer couplings under a tilted magnetic field. Near the center of the ring where the interlayer coupling is negligible, we have Dirac Landau levels which explain the appearance of the zero modes. Although the interlayer hopping amplitudes become finite at higher momenta, the splitting of zero modes is exponentially small and they remain almost flat due to the finite artificial in-plane component of the magnetic field. The emergence of the density of states peak at the Fermi level would be a hallmark of the ring dispersion.
3. Tuberculous Lymphadenitis Mimicking Nodal Metastasis in Follicular Variant Papillary Thyroid Carcinoma
Directory of Open Access Journals (Sweden)
Marc Gregory Yu
2016-01-01
Full Text Available Tuberculous (TB lymphadenitis can mimic cervical node metastasis from papillary thyroid carcinoma (PTC since the distribution and appearance of affected lymph nodes are similar. We present the case of an asymptomatic 50-year-old Filipino who sought consult for a gradually enlarging anterior neck mass and a single palpable cervical lymph node. Preoperative workup suggested a thyroid malignancy with nodal metastasis. He underwent total thyroidectomy with node dissection where histopathology confirmed follicular variant- (FV- PTC. Lymph node examination, however, revealed TB lymphadenitis, and the patient was given standard antimycobacterial therapy. This is the first documented case in Southeast Asia, a high TB burden region. This is also the first report involving FV-PTC, which has features between those of conventional PTC and follicular thyroid carcinoma. The case suggests that, in endemic areas, TB should be a differential in the etiology of cervical lymphadenopathy in PTC patients. In developed countries, this differential diagnosis is also valuable because of the increasing incidence of HIV and TB coinfection. Proper preoperative evaluation is important and needs to be highlighted in the formulation of local guidelines.
4. Tuberculous Lymphadenitis Mimicking Nodal Metastasis in Follicular Variant Papillary Thyroid Carcinoma
Science.gov (United States)
Atun, Jenny Maureen
2016-01-01
Tuberculous (TB) lymphadenitis can mimic cervical node metastasis from papillary thyroid carcinoma (PTC) since the distribution and appearance of affected lymph nodes are similar. We present the case of an asymptomatic 50-year-old Filipino who sought consult for a gradually enlarging anterior neck mass and a single palpable cervical lymph node. Preoperative workup suggested a thyroid malignancy with nodal metastasis. He underwent total thyroidectomy with node dissection where histopathology confirmed follicular variant- (FV-) PTC. Lymph node examination, however, revealed TB lymphadenitis, and the patient was given standard antimycobacterial therapy. This is the first documented case in Southeast Asia, a high TB burden region. This is also the first report involving FV-PTC, which has features between those of conventional PTC and follicular thyroid carcinoma. The case suggests that, in endemic areas, TB should be a differential in the etiology of cervical lymphadenopathy in PTC patients. In developed countries, this differential diagnosis is also valuable because of the increasing incidence of HIV and TB coinfection. Proper preoperative evaluation is important and needs to be highlighted in the formulation of local guidelines.
5. Linear stability analysis of flow instabilities with a nodalized reduced order model in heated channel
International Nuclear Information System (INIS)
The prime objective of the presented work is to develop a Nodalized Reduced Order Model (NROM) to carry linear stability analysis of flow instabilities in a two-phase flow system. The model is developed by dividing the single phase and two-phase region of a uniformly heated channel into N number of nodes followed by time dependent spatial linear approximations for single phase enthalpy and two-phase quality between the consecutive nodes. Moving boundary scheme has been adopted in the model, where all the node boundaries vary with time due to the variation of boiling boundary inside the heated channel. Using a state space approach, the instability thresholds are delineated by stability maps plotted in parameter planes of phase change number (Npch) and subcooling number (Nsub). The prime feature of the present model is that, though the model equations are simpler due to presence of linear-linear approximations for single phase enthalpy and two-phase quality, yet the results are in good agreement with the existing models (Karve [33]; Dokhane [34]) where the model equations run for several pages and experimental data (Solberg [41]). Unlike the existing ROMs, different two-phase friction factor multiplier correlations have been incorporated in the model. The applicability of various two-phase friction factor multipliers and their effects on stability behaviour have been depicted by carrying a comparative study. It is also observed that the Friedel model for friction factor calculations produces the most accurate results with respect to the available experimental data. (authors)
6. Analysis of heterogeneous boron dilution transients during outages with APROS 3D nodal core model
Energy Technology Data Exchange (ETDEWEB)
Kuopanportti, Jaakko [Fortum Power and Heat Ltd, Nuclear Production, Fortum (Finland)
2015-09-15
A diluted water plug can form inside the primary coolant circuit if the coolant flow has stopped at least temporarily. The source of the clean water can be external or the fresh water can build up internally during boiling/condensing heat transfer mode, which can occur if the primary coolant inventory has decreased enough during an accident. If the flow restarts in the stagnant primary loop, the diluted water plug can enter the reactor core. During outages after the fresh fuel has been loaded and the temperature of the coolant is low, the dilution potential is the highest because the critical boron concentration is at the maximum. This paper examines the behaviour of the core as clean or diluted water plugs of different sizes enter the core during outages. The analysis were performed with the APROS 3D nodal core model of Loviisa VVER-440, which contains an own flow channel and 10 axial nodes for each fuel assembly. The widerange cross section data was calculated with CASMO-4E. According to the results, the core can withstand even large pure water plugs without fuel failures on natural circulation. The analyses emphasize the importance of the simulation of the backflows inside the core when the reactor is on natural circulation.
7. Effect of including corner point fluxes on the pin power reconstruction using nodal point flux scheme
International Nuclear Information System (INIS)
Highlights: • Including corner fluxes improve pin power reconstruction. • The maximum errors in pin power reconstruction occur in the peripheral water region. • The errors are significantly less in the fuel region. • MSS predictions for corner pin flux are preferable. - Abstract: Although there have been well established transport based codes for core neutronics analysis, it is yet impractical to implement them in the real core treatment because their performance is not so great on ordinary server computers. For this reason, most of neutronics codes for core calculation are subject to two steps calculation procedure which consists of homogenized group constant generation and flux distribution generation which is the main concern of this work. This paper brings out a 2 dimensional nodal code based on point flux algorithm and implements two schemes for pin power reconstruction. In the first scheme, pin power reconstruction is obtained without considering corner point fluxes in the fuel assemblies but in the second method corner fluxes are included to assess their effect on pin power reconstruction. To obtain corner point fluxes, Smith’s procedure and the method of successive smoothing are used. Improvement in pin power reconstruction by including fuel assembly corner fluxes is illustrated in this paper and assessed by Monte Carlo simulation
8. Can we omit prophylactic inguinal nodal irradiation in anal cancer patients?
International Nuclear Information System (INIS)
To evaluate the appropriateness of prophylactic inguinal nodal irradiation (PINI), we analyzed patterns of failure in anal cancer patients who were inguinal node-negative at presentation and did not receive PINI. We retrospectively reviewed the records of 33 anal cancer patients treated by definitive concurrent chemoradiation therapy (CCRT) between 1994 and 2013. Radiotherapy consisted of a total dose of 44-45 Gy (22-25 fractions in 5 weeks) on the whole pelvis, anus, and perineum. Except inguinal lymphadenopathy was present at initial diagnosis, the entire inguinal chain was not included in the radiation field. In other words, there was no PINI. The median follow-up duration was 50 months (range, 4 to 218 months). Median survival and progression-free survival (PFS) were 57 months (range, 10 to 218 months) and 50 months (range, 4 to 218 months), respectively. Among the survival, the median follow-up duration was 51 months (range, 12 to 218 months). The 5-year overall survival and PFS rates were 93.4% and 88.8%, respectively. Although none of the patients received inguinal node irradiation for prophylactic purposes, there was no inguinal recurrence. Treatment of anal cancer by omitting PINI might be considered in selected patients with clinically uninvolved inguinal nodes
9. MICROPROPAGATION OF ADULT TREE OF PTEROCARPUS MARSUPIUM ROXB. USING NODAL EXPLANTS
Directory of Open Access Journals (Sweden)
Shipra JAISWAL
2015-12-01
Full Text Available Attempts were made for in vitro propagation of Pterocarpus marsupium Roxb., belonging to family Fabaceae, an economically important multipurpose tree. The tree is scared with noval antidiabetic properties. The tree shows poor seed germination capacity (30% due to hard seed coat and conventional vegetative regeneration methods are a complete failure. Therefore, the propagation of this tree by tissue culture techniques is an urgent need and well justified. Nodal segments containing axillary bud from 10 years old tree of P. marsupium were evaluated for axillary shoot proliferation on Murashige and Skoog’s (MS basal medium fortified with BAP (6–benzylaminopurine and kinetin (Kn singly or in combinations with auxins at different concentrations. The best shoot proliferation was obtained with 13.95 µM Kn + additives (568 µM Ascorbic acid, 260 µM Citric acid, 605 µM Ammonium sulphate and 217 µM Adenine sulphate in MS medium where 64.44% of the axillary buds responded with development of (2.51±0.10 shoots. Multiplication of in vitro shoots were achieved on MS Medium supplemented with Kn (9.30 µM + NAA (0.54 µM and additives. Half strength MS medium supplemented with 4.92 µM IBA induced in vitro rooting of in vitro shoots. In vitro regenerated plantlets with well developed roots were successfully hardened in a greenhouse.
10. Can we omit prophylactic inguinal nodal irradiation in anal cancer patients?
Energy Technology Data Exchange (ETDEWEB)
Kim, Ha Young; Park, Hee Chul; Yu, Jeong Il; Choi, Doo Ho; Ahn, Yong Chan; Kim, Seung Tae; Park, Joon Oh; Park, Young Suk; Kim, Hee Cheol [Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul (Korea, Republic of)
2015-06-15
To evaluate the appropriateness of prophylactic inguinal nodal irradiation (PINI), we analyzed patterns of failure in anal cancer patients who were inguinal node-negative at presentation and did not receive PINI. We retrospectively reviewed the records of 33 anal cancer patients treated by definitive concurrent chemoradiation therapy (CCRT) between 1994 and 2013. Radiotherapy consisted of a total dose of 44-45 Gy (22-25 fractions in 5 weeks) on the whole pelvis, anus, and perineum. Except inguinal lymphadenopathy was present at initial diagnosis, the entire inguinal chain was not included in the radiation field. In other words, there was no PINI. The median follow-up duration was 50 months (range, 4 to 218 months). Median survival and progression-free survival (PFS) were 57 months (range, 10 to 218 months) and 50 months (range, 4 to 218 months), respectively. Among the survival, the median follow-up duration was 51 months (range, 12 to 218 months). The 5-year overall survival and PFS rates were 93.4% and 88.8%, respectively. Although none of the patients received inguinal node irradiation for prophylactic purposes, there was no inguinal recurrence. Treatment of anal cancer by omitting PINI might be considered in selected patients with clinically uninvolved inguinal nodes.
11. Light Spectral Quality Effects on the Growth of Potato (Solanum Tuberosum L.) Nodal Cuttings in Vitro
Science.gov (United States)
Wilson, Deborah A.; Weigel, Russell C.; Wheeler, Raymond M.; Sager, John C.
1993-01-01
The effects of light spectral quality on the growth of in vitro nodal cuttings of potato (Solanum tuberosum L.) cultivars Norland, Superior, Kennebec, and Denali were examined. The different light spectra were provided by Vita-Lite fluorescent (VF) (a white light control), blue fluorescent (BF), red fluorescent (RF), low-pressure sodium (LPS), and a combination of low-pressure sodium plus cool-white fluorescent lamps (LPS/CWF). For cultivars, stem lengths after 4 wks were longest under LPS, follow by RF, LPS/CWF, VF, and BF (in descending order). Microscopic studies revealed that cells were shortest when cultured in BF or VF environments, and were longest in RF or LPS lamp environments. The highest number axillary branches occurred on plantlets grown with LPS or LPS/CWF, whereas the lowest number occurred with BF. No leaf or stem edema (callus or gall-like growths) occurred iwth LPS or LPS/cwf lighting, and no edema occurred on cv. Norland plantlets, regardless of lighting. Results suggest that shoot morphologic development of in vitro grown potato plants can be controlled by controlling irradiant spectral quality.
12. Reflector modelling with multi-group nodal equivalence theory for the SAFARI-1 research reactor
International Nuclear Information System (INIS)
Normalised Generalised Equivalence Theory is used to model the ex-core reflector region of the SAFARI-1 research reactor. This method is a one-dimensional homogenisation technique based on Generalised Equivalence Theory, but with only one discontinuity factor defined per node, and divided into the nodal parameters. The SAFARI-1 reactor is modelled with the deterministic code system OSCAR-4. Cross-sections for the reflector model is generated with NEWT (part of the SCALE 6.1 package) and EQUIVA-1 (part of OSCAR-4), which calculates the NGET parameters. A period of three years in the operational history of the SAFARI-1 research reactor is modelled. Two models are used, one with traditional flux-volume weighted and the other with equivalent ex-core reflector cross-sections. The performance of the two models over the three year period is compared. Reactor parameters such as reactivity and fuel burnup are investigated. Comparisons to experimental data, in particular control rod calibrations, are also made. The model with equivalent reflector parameters shows improved accuracy for control rod calibrations, a power tilt of about 10% across the core, no noticeable change in reactivity or burnup, and significant improvement in calculational time (reduced by over 40%) due to a reduction in the size of the core model. (author)
13. Analysis of the influence of elective nodal irradiation on postirradiation pulmonary function
International Nuclear Information System (INIS)
Irradiation (RT) field selection for bronchogenic carcinoma is based on such factors as extent of disease, pulmonary function, and the perceived need for elective nodal irradiation (ENI). A technique of superimposing a patient's RT treatment film onto his quantitative perfusion lung scan can predict the fractional volume of perfused lung receiving RT and has been shown to reliably estimate the minimum post-RT pulmonary function as measured by the forced expiratory volume in one second (FEV1). This technique has been applied to 20 patients with nonresected clinically staged T1-4N0M0 lesions to quantify the pulmonary impact of varying degrees of ENI. The five treatment volumes selected were as follows: (1) tumor volume plus a 2-cm margin; (2) volume 1 plus ipsilateral hilum; (3) volume 2 plus mediastinum; (4) volume 3 plus supraclavicular fossae; and (5) volume 4 plus contralateral hilum. The median pre-RT FEV1 was 2.0 l, and the median predicted minimal post-RT FEV1 for each proposed field was field 1, 1.7 l; field 2, 1.5 l; field 3, 1.3 l; field 4, 1.1.; and field 5, 1.0 l. The decline in median predicted FEV1 with each increase in field size ranged from 2% to 12%, with a broad range of declines for each field. Such quantification can aid in decisions regarding ENI for patients with impaired pulmonary function
14. A Case of Recurrent Eccrine Porocarcinoma with Regional Lymph Nodal Metastasis, Arising on a Bowen’s Disease Patch
OpenAIRE
Thuruthil, Rajesh Reghu; Jayalakshmy, P. S.; Sukumar, Vivek
2015-01-01
Eccrine carcinomas are very rare, comprising only less than 0.005 % of all cutaneous carcinomas, as reported by Goellner et al. (Cancer 56:1147–1162, 1985). We are reporting a case of recurrent eccrine porocarcinoma (EPC) with regional lymph nodal metastasis, which arose on a Bowen’s disease patch. Wide local excision of the lesion with lymph node dissection and excision of the Bowen’s disease was done.
15. Clonal propagation and synthetic seed production from nodal segments ofCape gooseberry (Physalis peruviana L.), a tropical fruit plant
OpenAIRE
YÜCESAN, BAHTİYAR BUHARA; MOHAMMED, ALİYU; Arslan, Merve; Gürel, Ekrem
2015-01-01
Physalis peruviana L. contains polyphenols and carotenoids with antiinflammatory and antioxidant activities used against diabetes. To establish an efficient regeneration system using nodal segments excised from 4-week-old germinated seedlings, direct plant regeneration, without additional rooting stage, was achieved on LS medium containing 0.5 mg/L 6-benzylaminopurine (BAP), kinetin (KIN), thidiazuron (TDZ), or gibberellic acid (GA3), alone or in combination with 0.25 mg/L indole-3-acetic aci...
16. Mathematical Formalism for Designing Wide-Field X-Ray Telescopes: Mirror Nodal Positions and Detector Tilts
Science.gov (United States)
Elsner, R. F.; O'Dell, S. L.; Ramsey, B. D.; Weisskopf, M. C.
2011-01-01
We provide a mathematical formalism for optimizing the mirror nodal positions along the optical axis and the tilt of a commonly employed detector configuration at the focus of a x-ray telescope consisting of nested mirror shells with known mirror surface prescriptions. We adopt the spatial resolution averaged over the field-of-view as the figure of merit M. A more complete description appears in our paper in these proceedings.
17. A nodal inverse problem for a quasi-linear ordinary differential equation in the half-line
Science.gov (United States)
Pinasco, Juan P.; Scarola, Cristian
2016-07-01
In this paper we study an inverse problem for a quasi-linear ordinary differential equation with a monotonic weight in the half-line. First, we find the asymptotic behavior of the singular eigenvalues, and we obtain a Weyl-type asymptotics imposing an appropriate integrability condition on the weight. Then, we investigate the inverse problem of recovering the coefficients from nodal data. We show that any dense subset of nodes of the eigenfunctions is enough to recover the weight.
18. Modelling horizontal steam generator with ATHLET. Verification of different nodalization schemes and implementation of verified constitutive equations
Energy Technology Data Exchange (ETDEWEB)
Beliaev, J.; Trunov, N.; Tschekin, I. [OKB Gidropress (Russian Federation); Luther, W. [GRS Garching (Germany); Spolitak, S. [RNC-KI (Russian Federation)
1995-12-31
Currently the ATHLET code is widely applied for modelling of several Power Plants of WWER type with horizontal steam generators. A main drawback of all these applications is the insufficient verification of the models for the steam generator. This paper presents the nodalization schemes for the secondary side of the steam generator, the results of stationary calculations, and preliminary comparisons to experimental data. The consideration of circulation in the water inventory of the secondary side is proved to be necessary. (orig.). 3 refs.
19. Diffuse large B-cell lymphoma: clinical implications of extranodal versus nodal presentation--a population-based study of 1575 cases
DEFF Research Database (Denmark)
Møller, Michael B; Pedersen, Niels T; Christensen, Bjarne E
2004-01-01
Differences in genetic origin between nodal and extranodal diffuse large B-cell lymphomas (DLBCL) exist. Using population-based data from the registry of the Danish Lymphoma Group, the present study is the first to analyse clinical implications of nodal versus extranodal presentation of DLBCL....... Of 4786 newly diagnosed non-Hodgkin's lymphoma patients in a 16-year period, 1575 (33%) had DLBCL. The annual incidence rate was 2.9 per 100 000; 40% were extranodal. The clinical profile of patients with extranodal DLBCL was different from the nodal DLBCL patients. Extranodal DLBCL was associated...... with older age and poorer performance score, but also lower tumour burden. In extranodal DLBCL, 51% of the cases were stage I and 36% were stage IV, whereas the patients were relatively equally distributed between the four stages in nodal DLBCL. For stage I patients, extranodal DLBCL was independently...
20. Fluorodeoxyglucose positron emission tomography-computed tomography in evaluation of pelvic and para-aortic nodal involvement in early stage and operable cervical cancer: comparison with surgicopathological findings
International Nuclear Information System (INIS)
Nodal metastases in cervical cancer have prognostic implications. Imaging is used as an adjunct to clinical staging for evaluation of nodal metastases. Fluorodeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT) has an advantage of superior resolution of its CT component and detecting nodal disease based on increased glycolytic activity rather than node size. But there are limited studies describing its limitations in early stage cervical cancers. We have done meta-analysis with an objective to evaluate the efficacy of FDG PET/CT and its current clinical role in early stage and operable cervical cancer. Studies in which FDG PET/CT was performed before surgery in patients with early stage cervical cancers were included for analysis. PET findings were confirmed with histopathological diagnosis rather than clinical follow-up. The current data suggest that FDG PET/CT is suboptimal in nodal staging in early stage cervical cancer
1. Work Coordination Engine
Science.gov (United States)
Zendejas, Silvino; Bui, Tung; Bui, Bach; Malhotra, Shantanu; Chen, Fannie; Kim, Rachel; Allen, Christopher; Luong, Ivy; Chang, George; Sadaqathulla, Syed
2009-01-01
The Work Coordination Engine (WCE) is a Java application integrated into the Service Management Database (SMDB), which coordinates the dispatching and monitoring of a work order system. WCE de-queues work orders from SMDB and orchestrates the dispatching of work to a registered set of software worker applications distributed over a set of local, or remote, heterogeneous computing systems. WCE monitors the execution of work orders once dispatched, and accepts the results of the work order by storing to the SMDB persistent store. The software leverages the use of a relational database, Java Messaging System (JMS), and Web Services using Simple Object Access Protocol (SOAP) technologies to implement an efficient work-order dispatching mechanism capable of coordinating the work of multiple computer servers on various platforms working concurrently on different, or similar, types of data or algorithmic processing. Existing (legacy) applications can be wrapped with a proxy object so that no changes to the application are needed to make them available for integration into the work order system as "workers." WCE automatically reschedules work orders that fail to be executed by one server to a different server if available. From initiation to completion, the system manages the execution state of work orders and workers via a well-defined set of events, states, and actions. It allows for configurable work-order execution timeouts by work-order type. This innovation eliminates a current processing bottleneck by providing a highly scalable, distributed work-order system used to quickly generate products needed by the Deep Space Network (DSN) to support space flight operations. WCE is driven by asynchronous messages delivered via JMS indicating the availability of new work or workers. It runs completely unattended in support of the lights-out operations concept in the DSN.
2. Absolute Branching Fraction Measurements of Exclusive D^+ Semileptonic Decays
CERN Document Server
Huang, G S; Pavlunin, V; Sanghi, B; Shipsey, I P J; Adams, G S; Chasse, M; Cravey, M; Cummings, J P; Danko, I; Napolitano, J; He, Q; Muramatsu, H; Park, C S; Park, W; Thorndike, E H; Coan, T E; Gao, Y S; Liu, F; Artuso, M; Boulahouache, C; Blusk, S; Butt, J; Dambasuren, E; Dorjkhaidav, O; Li, J; Menaa, N; Mountain, R; Nandakumar, R; Randrianarivony, K; Redjimi, R; Sia, R; Skwarnicki, T; Stone, S; Wang, J C; Zhang, K; Csorna, S E; Bonvicini, G; Cinabro, D; Dubrovin, M; Briere, R A; Chen, G P; Chen, J; Ferguson, T; Tatishvili, G T; Vogel, H; Watkins, M E; Rosner, J L; Adam, N E; Alexander, J P; Berkelman, K; Cassel, D G; Credé, V; Duboscq, J E; Ecklund, K M; Ehrlich, R; Fields, L; Gibbons, L; Gittelman, B; Gray, R; Gray, S W; Hartill, D L; Heltsley, B K; Hertz, D; Hsu, L; Jones, C D; Kandaswamy, J; Kreinick, D L; Kuznetsov, V E; Mahlke-Krüger, H; Meyer, T O; Onyisi, P U E; Patterson, J R; Peterson, D; Phillips, E A; Pivarski, J; Riley, D; Ryd, A; Sadoff, A J; Schwarthoff, H; Shi, X; Shepherd, M R; Stroiney, S; Sun, W M; Urner, D; Weaver, K M; Wilksen, T; Weinberger, M; Athar, S B; Avery, P; Breva-Newell, L; Patel, R; Potlia, V; Stöck, H; Yelton, J; Rubin, P; Cawlfield, C; Eisenstein, B I; Gollin, G D; Karliner, I; Kim, D; Lowrey, N; Naik, P; Sedlack, C; Selen, M; Williams, J; Wiss, J; Edwards, K W; Besson, D; Pedlar, T K; Cronin-Hennessy, D; Gao, K Y; Gong, D T; Hietala, J; Kubota, Y; Klein, T; Lang, B W; Li, S Z; Poling, R; Scott, A W; Smith, A; Dobbs, S; Metreveli, Z V; Seth, K K; Tomaradze, A G; Zweber, P; Ernst, J; Mahmood, A H; Severini, H; Asner, D M; Dytman, S A; Love, W; Mehrabyan, S S; Müller, J A; Savinov, V; Li, Z; López, A; Méndez, H; Ramírez, J
2005-01-01
Using data collected at the psi(3770) resonance with the CLEO-c detector at the Cornell e+e- storage ring, we present improved measurements of the absolute branching fractions of D+ decays to K0B e+ nu_e, pi0 e+ nu_e, K0B* e+ nu_e, and rho0 e+ nu_e, and the first observation and absolute branching fraction measurement of D+ --> omega e+ nu_e. We also report the most precise tests to date of isospin invariance in semileptonic D0 and D+ decays.
3. On the absolute value of the air-fluorescence yield
OpenAIRE
Rosado Vélez, Jaime; Blanco Ramos, Francisco; Arqueros Martínez, Fernando
2014-01-01
The absolute value of the air-fluorescence yield is a key parameter for the energy reconstruction of extensive air showers registered by fluorescence telescopes. In previous publications, we reported a detailed Monte Carlo simulation of the air-fluorescence generation that allowed the theoretical evaluation of this parameter. This simulation has been upgraded in the present work. As a result, we determined an updated absolute value of the fluorescence yield of 7.9 +/- 2.0 ph/MeV for the band ...
4. Properties of Absolute Stability in the Presence of Time Lags
Directory of Open Access Journals (Sweden)
M. De la Sen
2005-01-01
Full Text Available This study is concerned with the properties of absolute stability independent of the delays of time-delay systems, possessing non commensurate internal point delays, for any nonlinearity satisfying a Popov’s- type time positivity inequality. That property holds if an associate delay-free system is absolutely stable and the size of the delayed dynamics is sufficiently small. The results are obtained for nonlinearities belonging to sectors [0, k] and [h, k+h], and are based on a parabola test type.
5. Total Synthesis and Absolute Configuration of the Marine Norditerpenoid Xestenone
Directory of Open Access Journals (Sweden)
Hiroaki Miyaoka
2009-11-01
Full Text Available Xestenone is a marine norditerpenoid found in the northeastern Pacific sponge Xestospongia vanilla. The relative configuration of C-3 and C-7 in xestenone was determined by NOESY spectral analysis. However the relative configuration of C-12 and the absolute configuration of this compound were not determined. The authors have now achieved the total synthesis of xestenone using their developed one-pot synthesis of cyclopentane derivatives employing allyl phenyl sulfone and an epoxy iodide as a key step. The relative and absolute configurations of xestenone were thus successfully determined by this synthesis.
6. Absolute small-angle measurement based on optical feedback interferometry
Institute of Scientific and Technical Information of China (English)
Jingang Zhong; Xianhua Zhang; Zhixiang Ju
2008-01-01
We present a simple but effective method for small-angle measurement based on optical feedback inter-ferometry (or laser self-mixing interferometry). The absolute zero angle can be defined at the biggest fringe amplitude point, so this method can also achieve absolute angle measurement. In order to verify the method, we construct an angle measurement system. The Fourier-transform method is used to analysis the interference signal. Rotation angles are experimentally measured with a resolution of 10-6 rad and a measurement range of approximately from -0.0007 to +0.0007 rad.
7. Non-Invasive Method of Determining Absolute Intracranial Pressure
Science.gov (United States)
Yost, William T. (Inventor); Cantrell, John H., Jr. (Inventor); Hargens, Alan E. (Inventor)
2004-01-01
A method is presented for determining absolute intracranial pressure (ICP) in a patient. Skull expansion is monitored while changes in ICP are induced. The patient's blood pressure is measured when skull expansion is approximately zero. The measured blood pressure is indicative of a reference ICP value. Subsequently, the method causes a known change in ICP and measured the change in skull expansion associated therewith. The absolute ICP is a function of the reference ICP value, the known change in ICP and its associated change in skull expansion; and a measured change in skull expansion.
8. Perceiving pitch absolutely: Comparing absolute and relative pitch possessors in a pitch memory task
Directory of Open Access Journals (Sweden)
Schlaug Gottfried
2009-08-01
Full Text Available Abstract Background The perceptual-cognitive mechanisms and neural correlates of Absolute Pitch (AP are not fully understood. The aim of this fMRI study was to examine the neural network underlying AP using a pitch memory experiment and contrasting two groups of musicians with each other, those that have AP and those that do not. Results We found a common activation pattern for both groups that included the superior temporal gyrus (STG extending into the adjacent superior temporal sulcus (STS, the inferior parietal lobule (IPL extending into the adjacent intraparietal sulcus (IPS, the posterior part of the inferior frontal gyrus (IFG, the pre-supplementary motor area (pre-SMA, and superior lateral cerebellar regions. Significant between-group differences were seen in the left STS during the early encoding phase of the pitch memory task (more activation in AP musicians and in the right superior parietal lobule (SPL/intraparietal sulcus (IPS during the early perceptual phase (ITP 0–3 and later working memory/multimodal encoding phase of the pitch memory task (more activation in non-AP musicians. Non-significant between-group trends were seen in the posterior IFG (more in AP musicians and the IPL (more anterior activations in the non-AP group and more posterior activations in the AP group. Conclusion Since the increased activation of the left STS in AP musicians was observed during the early perceptual encoding phase and since the STS has been shown to be involved in categorization tasks, its activation might suggest that AP musicians involve categorization regions in tonal tasks. The increased activation of the right SPL/IPS in non-AP musicians indicates either an increased use of regions that are part of a tonal working memory (WM network, or the use of a multimodal encoding strategy such as the utilization of a visual-spatial mapping scheme (i.e., imagining notes on a staff or using a spatial coding for their relative pitch height for pitch
9. Correlation of primary tumor size and axillary nodal status with tumor suppressor gene p53 in breast carcinoma
Directory of Open Access Journals (Sweden)
Topić Brano
2002-01-01
Full Text Available Correlation of standard path morphological prognostic parameters, primary tumor size and axillary nodal status with new prognostic factor in breast carcinoma: tumor suppressor gene p53 was analyzed. The studied sample included 65 women who underwent surgery for breast carcinoma at the Surgical Clinic of Clinical Center Banja Luka, from January 1st 1997 till January 1st 1999. Statistical data analysis was performed and correlation of prognostic factors was determined. The majority of authors in this field agree that the primary tumor size and axillary nodal status are the two most important prognostic factors. These factors are the best predictors of prognosis and survival of women who had the tumor and were operated on. Tumor markers were immunohistochemically determined in the last ten years and, according to the majority of authors, are still considered the additional or relative prognostic factors in breast carcinoma. Their prognostic value and significance increase almost daily. Most frequently determined tumor markers are bcl-2, pS2, Ki-67 and p53. There was a positive, directly proportional relationship between primary tumor size and tumor suppressor gene p53, but there was no positive correlation between the axillary nodal status and tumor suppressor gene p53. Significance of determination of new tumor markers as the prognostic factors was emphasized. These markers represent a powerful tool in the early detection and prevention of breast carcinoma.
10. The Axillary Nodal Harvest in Breast Cancer Surgery Is Unchanged by Sentinel Node Biopsy or the Timing of Surgery
Directory of Open Access Journals (Sweden)
B. E. Byrne
2012-01-01
Full Text Available Introduction. Patients with a positive sentinel lymph node biopsy may undergo delayed completion axillary dissection. Where intraoperative analysis is available, immediate completion axillary dissection can be performed. Alternatively, patients may undergo primary axillary dissection for breast cancer, historically or when preoperative assessment suggests axillary metastases. This study aims to determine if there is a difference in the total number of lymph nodes or the number of metastatic nodes harvested between the 3 possible approaches. Methods. Three consecutive comparable groups of 50 consecutive patients who underwent axillary dissection in each of the above contexts were identified from the Portsmouth Breast Unit Database. Patient demographics, clinicopathological variables, and surgical treatment were recorded. The total pathological nodal count and the number of metastatic nodes were compared between the groups. Results. There were no differences in clinico-pathological features between the three groups for all features studied with the exception of breast surgical procedure (P<0.001. There were no differences in total nodal harvest (P=0.822 or in the number of positive nodes harvested (P=0.157 between the three groups. Conclusion. The three approaches to axillary clearance yield equivalent nodal harvests, suggesting oncological equivalence and robustness of surgical technique.
11. Efficacy and prognostic analysis of chemoradiotherapy in patients with thoracic esophageal squamous carcinoma with cervical lymph nodal metastasis alone
International Nuclear Information System (INIS)
The prognostic factors of thoracic esophageal squamous carcinoma with cervical lymph nodal metastasis (CLNM) have not been specifically investigated. This study was performed to analyze the efficacy and prognostic factors of chemoradiotherapy for thoracic esophageal carcinoma with CLNM alone. From 2002 to 2011, 139 patients with inoperable esophageal cancer who underwent chemoradiotherapy at the Sun Yat-Sen University were retrospectively analyzed. Median radiation doses were 60 Gy (range: 50–68 Gy). Univariate and multivariate analyses were performed to compare overall survival (OS) and progression-free survival (PFS). The 1- and 3-year OS rates were 68.2% and 27.9%, respectively. The 1- and 3-year PFS rates were 51.9% and 20.1%, respectively. The multivariate analysis demonstrated that response to treatment, T stage, pathological grade, and laterality of cervical lymph nodal metastases were independent prognostic factors for thoracic esophageal carcinoma with CLNM. Concurrent chemoradiotherapy is an important and hopeful treatment option for patients with esophageal cancer with CLNM alone. Our study has revealed that response to treatment, T stage, pathological grade and laterality of cervical lymph nodal metastases are significant prognostic factors for long-term survival
12. Negative predictive value of preoperative computed tomography in determining pathologic local invasion, nodal disease, and abdominal metastases in gastric cancer
Science.gov (United States)
Kagedan, D.J.; Frankul, F.; El-Sedfy, A.; McGregor, C.; Elmi, M.; Zagorski, B.; Dixon, M.E.; Mahar, A.L.; Vasilevska-Ristovska, J.; Helyer, L.; Rowsell, C.; Swallow, C.J.; Law, C.H.; Coburn, N.G.
2016-01-01
Background Before undergoing curative-intent resection of gastric adenocarcinoma (ga), most patients undergo abdominal computed tomography (ct) imaging to determine contraindications to resection (local invasion, distant metastases). However, the ability to detect contraindications is variable, and the literature is limited to single-institution studies. We sought to assess, on a population level, the clinical relevance of preoperative ct in evaluating the resectability of ga tumours in patients undergoing surgery. Methods In a provincial cancer registry, 2414 patients with ga diagnosed during 2005–2008 at 116 institutions were identified, and a primary chart review of radiology, operative, and pathology reports was performed for all patients. Preoperative abdominal ct reports were compared with intraoperative findings and final pathology reports (reference standard) to determine the negative predictive value (npv) of ct in assessing local invasion, nodal involvement, and intra-abdominal metastases. Results Among patients undergoing gastrectomy, the npv of ct imaging in detecting local invasion was 86.9% (n = 536). For nodal metastasis, the npv of ct was 43.3% (n = 450). Among patients undergoing surgical exploration, the npv of ct for intra-abdominal metastases was 52.3% (n = 407). Conclusions Preoperative abdominal ct imaging reported as negative is most accurate in determining local invasion and least accurate in nodal assessment. The poor npv of ct should be taken into account when selecting patients for staging laparoscopy. PMID:27536178
13. Influence of Nodalization on Major Thermal-Hydraulic Variables Governing Mark-I Containment Response to an SBO Sequence: Plant Assessment
Energy Technology Data Exchange (ETDEWEB)
Herranz, L. E.; Fontanet, J.; Fernandez, E.; Lopez, C.
2014-07-01
Simulating a severe accident with lumped parameter codes, like MELCOR 2.1, requires defining a suitable nodalization of the plant. In particular, the number of nodes the wet-well (WW) is divided into and the way these nodes are interconnected have an important effect on thermal-hydraulics estimates of the containment. Therefore, a quantitative assessment of the effect of WW nodalization on accident sequence is needed when performing plant analyses. (Author)
14. Selective Nodal Irradiation on Basis of 18FDG-PET Scans in Limited-Disease Small-Cell Lung Cancer: A Prospective Study
International Nuclear Information System (INIS)
Purpose: To evaluate the results of selective nodal irradiation on basis of 18F-deoxyglucose positron emission tomography (PET) scans in patients with limited-disease small-cell lung cancer (LD-SCLC) on isolated nodal failure. Methods and Materials: A prospective study was performed of 60 patients with LD-SCLC. Radiotherapy was given to a dose of 45 Gy in twice-daily fractions of 1.5 Gy, concurrent with carboplatin and etoposide chemotherapy. Only the primary tumor and the mediastinal lymph nodes involved on the pretreatment PET scan were irradiated. A chest computed tomography (CT) scan was performed 3 months after radiotherapy completion and every 6 months thereafter. Results: A difference was seen in the involved nodal stations between the pretreatment 18F-deoxyglucose PET scans and computed tomography scans in 30% of patients (95% confidence interval, 20-43%). Of the 60 patients, 39 (65%; 95% confidence interval [CI], 52-76%) developed a recurrence; 2 patients (3%, 95% CI, 1-11%) experienced isolated regional failure. The median actuarial overall survival was 19 months (95% CI, 17-21). The median actuarial progression-free survival was 14 months (95% CI, 12-16). 12% (95% CI, 6-22%) of patients experienced acute Grade 3 (Common Terminology Criteria for Adverse Events, version 3.0) esophagitis. Conclusion: PET-based selective nodal irradiation for LD-SCLC resulted in a low rate of isolated nodal failures (3%), with a low percentage of acute esophagitis. These findings are in contrast to those from our prospective study of CT-based selective nodal irradiation, which resulted in an unexpectedly high percentage of isolated nodal failures (11%). Because of the low rate of isolated nodal failures and toxicity, we believe that our data support the use of PET-based SNI for LD-SCLC.
15. Coordination Processes in International Organisations
DEFF Research Database (Denmark)
Nedergaard, Peter
2008-01-01
The EU is not a member of the International Labour Organisation (ILO), but relatively elaborate EU coordination takes place anyway. This paper addresses two research questions: 1) How is it possible to evaluate the coordination of the EU in its specific observable configuration in the ILO?, and 2...... to coordinate relatively elaborate agreements due to the strength of its coordination as far as professional or technical and political activities (excepting the ILO budget) are concerned. In other more clear-cut or 'simple' policy areas such as the ILO budget, the EU coordination is weak: this contrast...
16. Final Report, NERI Project: ''An Innovative Reactor Analysis Methodology Based on a Quasidiffusion Nodal Core Model''
Energy Technology Data Exchange (ETDEWEB)
Dmitriy Y. Anistratov; Marvin L. Adams; Todd S. Palmer; Kord S. Smith; Kevin Clarno; Hikaru Hiruta; Razvan Nes
2003-08-04
OAK (B204) Final Report, NERI Project: ''An Innovative Reactor Analysis Methodology Based on a Quasidiffusion Nodal Core Model'' The present generation of reactor analysis methods uses few-group nodal diffusion approximations to calculate full-core eigenvalues and power distributions. The cross sections, diffusion coefficients, and discontinuity factors (collectively called ''group constants'') in the nodal diffusion equations are parameterized as functions of many variables, ranging from the obvious (temperature, boron concentration, etc.) to the more obscure (spectral index, moderator temperature history, etc.). These group constants, and their variations as functions of the many variables, are calculated by assembly-level transport codes. The current methodology has two main weaknesses that this project addressed. The first weakness is the diffusion approximation in the full-core calculation; this can be significantly inaccurate at interfaces between different assemblies. This project used the nodal diffusion framework to implement nodal quasidiffusion equations, which can capture transport effects to an arbitrary degree of accuracy. The second weakness is in the parameterization of the group constants; current models do not always perform well, especially at interfaces between unlike assemblies. The project developed a theoretical foundation for parameterization and homogenization models and used that theory to devise improved models. The new models were extended to tabulate information that the nodal quasidiffusion equations can use to capture transport effects in full-core calculations.
17. Evaluating the Relational Coordination instrument
DEFF Research Database (Denmark)
Edwards, Kasper; Lundstrøm, Sanne Lykke
2014-01-01
Relational coordination rests on the idea that coordination is a central issue in all work and that coordination happens through communication, which in turn is shaped by relations. Relational coordination is quite interesting because it has been shown to correlate with on-time flight departures...... and surgical performance. This has prompted the attention of both practitioners and politicians some of who perceive relational coordination as a means to attain better performance. The relational coordination instrument has been validated as a measure of teamwork from the following perspectives: internal...... consistency, interrater agreement and reliability, structural validity, content validity. However as relational coordination is being used as a diagnostics tool it is important to examine further if the instrument can measure changes. Indeed we need to know how precise and sensitive the instrument is when...
18. Absolute determination of inelastic mean-free paths and surface excitation parameters by absolute reflection electron energy loss spectrum analysis
Science.gov (United States)
Nagatomi, T.; Goto, K.
2005-11-01
An analytical approach was proposed for simultaneously determining an inelastic mean-free path (IMFP) and a surface excitation parameter (SEP) with absolute units by the analysis of an absolute experimental reflection electron energy loss spectrum. The IMFPs and SEPs in Ni were deduced for electrons of 300 to 3000 eV. The obtained IMFPs were in good agreement with those calculated using the TPP-2M equation. The Chen-type empirical formula was proposed for determining the SEP. The results confirmed the applicability of the present approach for determining the IMFP and SEP for medium-energy electrons.
19. Is sentinel lymph node biopsy more accurate than axillary dissection for staging nodal involvement in breast cancer patients?
Science.gov (United States)
Marrazzo, Antonio; Taormina, Pietra; Gebbiab, Vittorio; David, Massimo; Riili, Ignazio; Lo Gerfo, Domenico; Casà, Luigi; Noto, Antonio
2007-01-01
Today evaluation of axillary involvement can be routinely performed with the technique of sentinel lymph node biopsy (SLNB). One of the greatest advantages of SLNB is the nearly total absence of local postoperative complications. It is important to understand whether SLNB is better than axillary lymph-node dissection (ALND) for staging axillary nodal involvement. The aim of the study was to evaluate the axillary staging accuracy comparing three different methods: axillary dissection, sentinel node biopsy with the traditional 4-6 sections and sentinel node biopsy with complete analysis of the lymph node. 527 consecutive patients (525 females and 2 males) with invasive breast cancer < or = 3 cm and clinically negative axillary nodes were divided into 3 different groups: group A treated with axillary dissection, group B treated with sentinel nodal biopsy analysed with 4-6 sections, and group C treated with sentinel node biopsy with analysis of the entire node. All patients underwent a quadrantectomy to treat the tumor. Group differences and statistical significance were assessed by ANOVA. The percentages of N+ in group A and group B were 25.80% and 28% respectively, while in the third group it rose to 45%, or almost half the patients. The differences among the three groups were statistically significant (p = 0.02). From our analysis of the data it emerges that axillary dissection and sentinel node biopsy with analysis of 4-6 sections have the same accuracy in staging the nodal status of the axilla; analysis of the entire sentinel lymph node revealed an increased number of patients with axillary nodal involvement, proving more powerful in predicting nodal stage. SLNB with complete examination of the SLN removed can be considered the best method for axillary staging in breast cancer patients with clinical negative nodes. In our study, the percentage of metastases encountered after complete examination of SLN was 45% compared to the accuracy of axillary dissection that
20. Preoperative nodal staging of non-small cell lung cancer using 99mTc-sestamibi spect/ct imaging
Directory of Open Access Journals (Sweden)
Juliana Muniz Miziara
2011-01-01
Full Text Available OBJECTIVES: The proper nodal staging of non-small cell lung cancer is important for choosing the best treatment modality. Although computed tomography remains the first-line imaging test for the primary staging of lung cancer, its limitations for mediastinum nodal staging are well known. The aim of this study is to evaluate the accuracy of hybrid single-photon emission computed tomography and computed tomography using 99mTc-sestamibi in the nodal staging of patients with non-small cell lung cancer and to identify potential candidates for surgical treatment. METHODS: Prospective data were collected for 41 patients from December 2006 to February 2009. The patients underwent chest computed tomography and single-photon emission computed tomography/computed tomography examinations with 99mTc-sestamibi within a 30-day time period before surgery. Single-photon emission computed tomography/computed tomography was considered positive when there was focal uptake of sestamibi in the mediastinum, and computed tomography scan when there was lymph nodes larger than 10 mm in short axis. The results of single-photon emission computed tomography and computed tomography were correlated with pathology findings after surgery. RESULTS: Single-photon emission computed tomography/computed tomography correctly identified six out of 19 cases involving hilar lymph nodes and one out of seven cases involving nodal metastases in the mediastinum. The sensitivity, specificity, positive predictive value, and negative predictive value for 99mTc-sestamibi single-photon emission computed tomography/computed tomography in the hilum assessment were 31.6%, 95.5%, 85.7%, and 61.8%, respectively. The same values for the mediastinum were 14.3%, 97.1%, 50%, and 84.6%, respectively. For the hilar and mediastinal lymph nodes, chest tomography showed sensitivity values of 47.4% and 57.1%, specificity values of 95.5% and 91.2%, positive predictive values of 90% and 57.1% and negative
1. Partial sums of arithmetical functions with absolutely convergent Ramanujan expansions
BISWAJYOTI SAHA
2016-08-01
For an arithmetical function $f$ with absolutely convergent Ramanujan expansion, we derive an asymptotic formula for the $\\sum_{n\\leq N}$ f(n)\$ with explicit error term. As a corollary we obtain new results about sum-of-divisors functions and Jordan’s totient functions.
2. Absolute cross-section of turbojet aviation engine calculation
OpenAIRE
Ryabokon, Evgen
2012-01-01
The calculation method of three-dimensional model of turbojet aviation engine is offered, thus the form of turbine vanes with spiralling is described like parametric surface. The method allows make the calculation of absolute cross-section (ACS) of turbojet aviation engines with different geometrical parameters. The calculation results of ACS of aviation engine are presented.
3. Absolute Value Inequalities: High School Students' Solutions and Misconceptions
Science.gov (United States)
Almog, Nava; Ilany, Bat-Sheva
2012-01-01
Inequalities are one of the foundational subjects in high school math curricula, but there is a lack of academic research into how students learn certain types of inequalities. This article fills part of the research gap by presenting the findings of a study that examined high school students' methods of approaching absolute value inequalities,…
4. Gray- and White-Matter Anatomy of Absolute Pitch Possessors
DEFF Research Database (Denmark)
Dohn, Anders; Garza-Villarreal, Eduardo A.; Chakravarty, Mallar;
2015-01-01
Absolute pitch (AP), the ability to identify a musical pitch without a reference, has been examined behaviorally in numerous studies for more than a century, yet only a few studies have examined the neuroanatomical correlates of AP. Here, we used MRI and diffusion tensor imaging to investigate...
5. Absolute magnitudes and phase coefficients of trans-Neptunian objects
CERN Document Server
Alvarez-Candal, A; Ortiz, J L; Duffard, R; Morales, N; Santos-Sanz, P; Thirouin, A; Silva, J S
2015-01-01
Context: Accurate measurements of diameters of trans-Neptunian objects are extremely complicated to obtain. Thermal modeling can provide good results, but accurate absolute magnitudes are needed to constrain the thermal models and derive diameters and geometric albedos. The absolute magnitude, Hv, is defined as the magnitude of the object reduced to unit helio- and geocentric distances and a zero solar phase angle and is determined using phase curves. Phase coefficients can also be obtained from phase curves. These are related to surface properties, yet not many are known. Aims: Our objective is to measure accurate V band absolute magnitudes and phase coefficients for a sample of trans-Neptunian objects, many of which have been observed, and modeled, within the 'TNOs are cool' program, one of Herschel Space Observatory key projects. Methods: We observed 56 objects using the V and R filters. These data, along with those available in the literature, were used to obtain phase curves and measure V band absolute m...
6. Multipliers for the Absolute Euler Summability of Fourier Series
Prem Chandra
2001-05-01
In this paper, the author has investigated necessary and sufficient conditions for the absolute Euler summability of the Fourier series with multipliers. These conditions are weaker than those obtained earlier by some workers. It is further shown that the multipliers are best possible in certain sense.
7. Absolute luminosity measurements with the LHCb detector at the LHC
CERN Document Server
Aaij, R; Adinolfi, M; Adrover, C; Affolder, A; Ajaltouni, Z; Albrecht, J; Alessio, F; Alexander, M; Alkhazov, G; Alvarez Cartelle, P; Alves, A A; Amato, S; Amhis, Y; Anderson, J; Appleby, R B; Aquines Gutierrez, O; Archilli, F; Arrabito, L; Artamonov, A; Artuso, M; Aslanides, E; Auriemma, G; Bachmann, S; Back, J J; Bailey, D S; Balagura, V; Baldini, W; Barlow, R J; Barschel, C; Barsuk, S; Barter, W; Bates, A; Bauer, C; Bauer, Th; Bay, A; Bediaga, I; Belous, K; Belyaev, I; Ben-Haim, E; Benayoun, M; Bencivenni, G; Benson, S; Benton, J; Bernet, R; Bettler, M-O; van Beuzekom, M; Bien, A; Bifani, S; Bizzeti, A; Bjørnstad, P M; Blake, T; Blanc, F; Blanks, C; Blouw, J; Blusk, S; Bobrov, A; Bocci, V; Bondar, A; Bondar, N; Bonivento, W; Borghi, S; Borgia, A; Bowcock, T J V; Bozzi, C; Brambach, T; van den Brand, J; Bressieux, J; Brett, D; Brisbane, S; Britsch, M; Britton, T; Brook, N H; Brown, H; Büchler-Germann, A; Burducea, I; Bursche, A; Buytaert, J; Cadeddu, S; Caicedo Carvajal, J M; Callot, O; Calvi, M; Calvo Gomez, M; Camboni, A; Campana, P; Carbone, A; Carboni, G; Cardinale, R; Cardini, A; Carson, L; Carvalho Akiba, K; Casse, G; Cattaneo, M; Charles, M; Charpentier, Ph; Chiapolini, N; Ciba, K; Cid Vidal, X; Ciezarek, G; Clarke, P E L; Clemencic, M; Cliff, H V; Closier, J; Coca, C; Coco, V; Cogan, J; Collins, P; Constantin, F; Conti, G; Contu, A; Cook, A; Coombes, M; Corti, G; Cowan, G A; Currie, R; D'Almagne, B; D'Ambrosio, C; David, P; De Bonis, I; De Capua, S; De Cian, M; De Lorenzi, F; De Miranda, J M; De Paula, L; De Simone, P; Decamp, D; Deckenhoff, M; Degaudenzi, H; Deissenroth, M; Del Buono, L; Deplano, C; Deschamps, O; Dettori, F; Dickens, J; Dijkstra, H; Diniz Batista, P; Donleavy, S; Dordei, F; Dosil Suárez, A; Dossett, D; Dovbnya, A; Dupertuis, F; Dzhelyadin, R; Eames, C; Easo, S; Egede, U; Egorychev, V; Eidelman, S; van Eijk, D; Eisele, F; Eisenhardt, S; Ekelhof, R; Eklund, L; Elsasser, Ch; d'Enterria, D G; Esperante Pereira, D; Estève, L; Falabella, A; Fanchini, E; Färber, C; Fardell, G; Farinelli, C; Farry, S; Fave, V; Fernandez Albor, V; Ferro-Luzzi, M; Filippov, S; Fitzpatrick, C; Fontana, M; Fontanelli, F; Forty, R; Frank, M; Frei, C; Frosini, M; Furcas, S; Gallas Torreira, A; Galli, D; Gandelman, M; Gandini, P; Gao, Y; Garnier, J-C; Garofoli, J; Garra Tico, J; Garrido, L; Gaspar, C; Gauvin, N; Gersabeck, M; Gershon, T; Ghez, Ph; Gibson, V; Gligorov, V V; Göbel, C; Golubkov, D; Golutvin, A; Gomes, A; Gordon, H; Grabalosa Gándara, M; Graciani Diaz, R; Granado Cardoso, L A; Graugés, E; Graziani, G; Grecu, A; Gregson, S; Gui, B; Gushchin, E; Guz, Yu; Gys, T; Haefeli, G; Haen, C; Haines, S C; Hampson, T; Hansmann-Menzemer, S; Harji, R; Harnew, N; Harrison, J; Harrison, P F; He, J; Heijne, V; Hennessy, K; Henrard, P; Hernando Morata, J A; van Herwijnen, E; Hicks, E; Hofmann, W; Holubyev, K; Hopchev, P; Hulsbergen, W; Hunt, P; Huse, T; Huston, R S; Hutchcroft, D; Hynds, D; Iakovenko, V; Ilten, P; Imong, J; Jacobsson, R; Jaeger, A; Jahjah Hussein, M; Jans, E; Jansen, F; Jaton, P; Jean-Marie, B; Jing, F; John, M; Johnson, D; Jones, C R; Jost, B; Kandybei, S; Karacson, M; Karbach, T M; Keaveney, J; Kerzel, U; Ketel, T; Keune, A; Khanji, B; Kim, Y M; Knecht, M; Koblitz, S; Koppenburg, P; Kozlinskiy, A; Kravchuk, L; Kreplin, K; Kreps, M; Krocker, G; Krokovny, P; Kruse, F; Kruzelecki, K; Kucharczyk, M; Kukulak, S; Kumar, R; Kvaratskheliya, T; La Thi, V N; Lacarrere, D; Lafferty, G; Lai, A; Lambert, D; Lambert, R W; Lanciotti, E; Lanfranchi, G; Langenbruch, C; Latham, T; Le Gac, R; van Leerdam, J; Lees, J-P; Lefèvre, R; Leflat, A; Lefrançois, J; Leroy, O; Lesiak, T; Li, L; Li Gioi, L; Lieng, M; Liles, M; Lindner, R; Linn, C; Liu, B; Liu, G; Lopes, J H; Lopez Asamar, E; Lopez-March, N; Luisier, J; Machefert, F; Machikhiliyan, I V; Maciuc, F; Maev, O; Magnin, J; Malde, S; Mamunur, R M D; Manca, G; Mancinelli, G; Mangiafave, N; Marconi, U; Märki, R; Marks, J; Martellotti, G; Martens, A; Martin, L; Martín Sánchez, A; Martinez Santos, D; Massafferri, A; Matev, R; Mathe, Z; Matteuzzi, C; Matveev, M; Maurice, E; Maynard, B; Mazurov, A; McGregor, G; McNulty, R; Mclean, C; Meissner, M; Merk, M; Merkel, J; Messi, R; Miglioranzi, S; Milanes, D A; Minard, M-N; Monteil, S; Moran, D; Morawski, P; Mountain, R; Mous, I; Muheim, F; Müller, K; Muresan, R; Muryn, B; Musy, M; Mylroie-Smith, J; Naik, P; Nakada, T; Nandakumar, R; Nardulli, J; Nasteva, I; Nedos, M; Needham, M; Neufeld, N; Nguyen-Mau, C; Nicol, M; Nies, S; Niess, V; Nikitin, N; Oblakowska-Mucha, A; Obraztsov, V; Oggero, S; Ogilvy, S; Okhrimenko, O; Oldeman, R; Orlandea, M; Otalora Goicochea, J M; Owen, P; Pal, B; Palacios, J; Palutan, M; Panman, J; Papanestis, A; Pappagallo, M; Parkes, C; Parkinson, C J; Passaleva, G; Patel, G D; Patel, M; Paterson, S K; Patrick, G N; Patrignani, C; Pavel-Nicorescu, C
2012-01-01
Absolute luminosity measurements are of general interest for colliding-beam experiments at storage rings. These measurements are necessary to determine the absolute cross-sections of reaction processes and are valuable to quantify the performance of the accelerator. LHCb has applied two methods to determine the absolute scale of its luminosity measurements for proton-proton collisions at the LHC with a centre-of-mass energy of 7 TeV. In addition to the classic `van der Meer scan'' method a novel technique has been developed which makes use of direct imaging of the individual beams using beam-gas and beam-beam interactions. This beam imaging method is made possible by the high resolution of the LHCb vertex detector and the close proximity of the detector to the beams, and allows beam parameters such as positions, angles and widths to be determined. The results of the two methods have comparable precision and are in good agreement. Combining the two methods, an overall precision of 3.5\\% in the absolute lumi...
8. Confirmation of the absolute configuration of (−)-aurantioclavine
KAUST Repository
Behenna, Douglas C.
2011-04-01
We confirm our previous assignment of the absolute configuration of (-)-aurantioclavine as 7R by crystallographically characterizing an advanced 3-bromoindole intermediate reported in our previous synthesis. This analysis also provides additional support for our model of enantioinduction in the palladium(II)-catalyzed oxidative kinetic resolution of secondary alcohols. © 2010 Elsevier Ltd. All rights reserved.
9. Modeling and forecasting outliers and level shifts in absolute returns
NARCIS (Netherlands)
Ph.H.B.F. Franses (Philip Hans); M.J. van der Leij (Marco); R. Paap (Richard)
2001-01-01
textabstractDue to high and low volatility periods, time series of absolute returns experience temporary level shifts (that is, periods with outliers) which differ in length and size. In this paper we put forward a new model which can describe and forecast the location and size of such level shifts.
10. Determination of absolute structure using Bayesian statistics on Bijvoet differences
NARCIS (Netherlands)
Hooft, R.W.W.; Straver, L.H.; Spek, A.L.
2008-01-01
A new probabilistic approach is introduced for the determination of the absolute structure of a compound which is known to be enantiopure based on Bijvoet-pair intensity differences. The new method provides relative probabilities for different models of the chiral composition of the structure. The o
11. An improved generalized Newton method for absolute value equations.
Science.gov (United States)
Feng, Jingmei; Liu, Sanyang
2016-01-01
In this paper, we suggest and analyze an improved generalized Newton method for solving the NP-hard absolute value equations [Formula: see text] when the singular values of A exceed 1. We show that the global and local quadratic convergence of the proposed method. Numerical experiments show the efficiency of the method and the high accuracy of calculation. PMID:27462490
12. Global Absolute Poverty: Behind the Veil of Dollars
NARCIS (Netherlands)
Moatsos, M.
2015-01-01
The global absolute poverty rates of the World Bank demonstrate a continued decline of poverty in developing countries between 1983 and 2012. However, the methodology applied to derive these results has received extensive criticism by scholars for requiring the application of PPP exchange rates and
13. Absolute localization of vibrotactile stimuli on the torso
NARCIS (Netherlands)
Erp, J.B.F. van
2008-01-01
Vibrotactile mobility systems present spatial information such as the direction of a waypoint through a localized vibration on the torso. Using these systems requires the ability to determine the absolute location of the stimulus. Because data are available only on the ability to determine the relat
14. Estimation of Transition Probabilities Using Median Absolute Deviations
OpenAIRE
Kim, C. S.; Schaible, Glenn D.
1988-01-01
The probability-constrained minimum absolute deviations (MAD) estimator appears to be superior to the probability-constrained quadratic programming estimator in estimating transition probabilities with limited aggregate time series data Futhermore, one can reduce the number of columns in the probability-constrained MAD simplex tableau by adopting the median property
15. Mathematical Model for Absolute Magnetic Measuring Systems in Industrial Applications
Science.gov (United States)
Fügenschuh, Armin; Fügenschuh, Marzena; Ludszuweit, Marina; Mojsic, Aleksandar; Sokół, Joanna
2015-09-01
Scales for measuring systems are either based on incremental or absolute measuring methods. Incremental scales need to initialize a measurement cycle at a reference point. From there, the position is computed by counting increments of a periodic graduation. Absolute methods do not need reference points, since the position can be read directly from the scale. The positions on the complete scales are encoded using two incremental tracks with different graduation. We present a new method for absolute measuring using only one track for position encoding up to micrometre range. Instead of the common perpendicular magnetic areas, we use a pattern of trapezoidal magnetic areas, to store more complex information. For positioning, we use the magnetic field where every position is characterized by a set of values measured by a hall sensor array. We implement a method for reconstruction of absolute positions from the set of unique measured values. We compare two patterns with respect to uniqueness, accuracy, stability and robustness of positioning. We discuss how stability and robustness are influenced by different errors during the measurement in real applications and how those errors can be compensated.
16. Absolute magnitudes and phase coefficients of trans-Neptunian objects
Science.gov (United States)
Alvarez-Candal, A.; Pinilla-Alonso, N.; Ortiz, J. L.; Duffard, R.; Morales, N.; Santos-Sanz, P.; Thirouin, A.; Silva, J. S.
2016-02-01
Context. Accurate measurements of diameters of trans-Neptunian objects (TNOs) are extremely difficult to obtain. Thermal modeling can provide good results, but accurate absolute magnitudes are needed to constrain the thermal models and derive diameters and geometric albedos. The absolute magnitude, HV, is defined as the magnitude of the object reduced to unit helio- and geocentric distances and a zero solar phase angle and is determined using phase curves. Phase coefficients can also be obtained from phase curves. These are related to surface properties, but only few are known. Aims: Our objective is to measure accurate V-band absolute magnitudes and phase coefficients for a sample of TNOs, many of which have been observed and modeled within the program "TNOs are cool", which is one of the Herschel Space Observatory key projects. Methods: We observed 56 objects using the V and R filters. These data, along with those available in the literature, were used to obtain phase curves and measure V-band absolute magnitudes and phase coefficients by assuming a linear trend of the phase curves and considering a magnitude variability that is due to the rotational light-curve. Results: We obtained 237 new magnitudes for the 56 objects, six of which were without previously reported measurements. Including the data from the literature, we report a total of 110 absolute magnitudes with their respective phase coefficients. The average value of HV is 6.39, bracketed by a minimum of 14.60 and a maximum of -1.12. For the phase coefficients we report a median value of 0.10 mag per degree and a very large dispersion, ranging from -0.88 up to 1.35 mag per degree.
17. Absolute V-R colors of trans-Neptunian objects
Science.gov (United States)
Alvarez-Candal, Alvaro; Ayala-Loera, Carmen; Ortiz, Jose-Luis; Duffard, Rene; Estela, Fernandez-Valenzuela; Santos-Sanz, Pablo
2016-10-01
The absolute magnitude of a minor body is the apparent magnitude that the body would have if observed from the Sun at a distance of 1AU. Absolute magnitudes are measured using phase curves, showing the change of the magnitude, normalized to unit helio and geo-centric distance, vs. phase angle. The absolute magnitude is then the Y-intercept of the curve. Absolute magnitudes are related to the total reflecting surface of the body and thus bring information of its size, coupled with the reflecting properties.Since 2011 our team has been collecting data from several telescopes spread in Europe and South America. We complemented our data with those available in the literature in order to construct phase curves of trans-Neptunian objects with at least three points. In a first release (Alvarez-Candal et al. 2016, A&A, 586, A155) we showed results for 110 trans-Neptunian objects using V magnitudes only, assuming an overall linear trend and taking into consideration rotational effects, for objects with known light-curves.In this contribution we show results for more than 130 objects, about 100 of them with phase curves in two filters: V and R. We compute absolute magnitudes and phase coefficients in both filters, when available. The average values are HV = 6.39 ± 2.37, βV = (0.09 ± 0.32) mag per degree, HR = 5.38 ± 2.30, and βR = (0.08 ± 0.42) mag per degree.
18. Coordination using Implicit Communication
CERN Document Server
Cuff, Paul
2011-01-01
We explore a basic noise-free signaling scenario where coordination and communication are naturally merged. A random signal X_1,...,X_n is processed to produce a control signal or action sequence A_1,...,A_n, which is observed and further processed (without access to X_1,...,X_n) to produce a third sequence B_1,...,B_n. The object of interest is the set of empirical joint distributions p(x,a,b) that can be achieved in this setting. We show that H(A) >= I(X;A,B) is the necessary and sufficient condition for achieving p(x,a,b) when no causality constraints are enforced on the encoders. We also give results for various causality constraints. This setting sheds light on the embedding of digital information in analog signals, a concept that is exploited in digital watermarking, steganography, cooperative communication, and strategic play in team games such as bridge.
19. Network Coordinator Report
Science.gov (United States)
Himwich, Ed; Strand, Richard
2013-01-01
This report includes an assessment of the network performance in terms of lost observing time for the 2012 calendar year. Overall, the observing time loss was about 12.3%, which is in-line with previous years. A table of relative incidence of problems with various subsystems is presented. The most significant identified causes of loss were electronics rack problems (accounting for about 21.8% of losses), antenna reliability (18.1%), RFI (11.8%), and receiver problems (11.7%). About 14.2% of the losses occurred for unknown reasons. New antennas are under development in the USA, Germany, and Spain. There are plans for new telescopes in Norway and Sweden. Other activities of the Network Coordinator are summarized.
20. PTK 7 is a transforming gene and prognostic marker for breast cancer and nodal metastasis involvement.
Directory of Open Access Journals (Sweden)
Silvia Gärtner
Full Text Available Protein Tyrosin Kinase 7 (PTK7 is upregulated in several human cancers; however, its clinical implication in breast cancer (BC and lymph node (LN is still unclear. In order to investigate the function of PTK7 in mediating BC cell motility and invasivity, PTK7 expression in BC cell lines was determined. PTK7 signaling in highly invasive breast cancer cells was inhibited by a dominant-negative PTK7 mutant, an antibody against the extracellular domain of PTK7, and siRNA knockdown of PTK7. This resulted in decreased motility and invasivity of BC cells. We further examined PTK7 expression in BC and LN tissue of 128 BC patients by RT-PCR and its correlation with BC related genes like HER2, HER3, PAI1, MMP1, K19, and CD44. Expression profiling in BC cell lines and primary tumors showed association of PTK7 with ER/PR/HER2-negative (TNBC-triple negative BC cancer. Oncomine data analysis confirmed this observation and classified PTK7 in a cluster with genes associated with agressive behavior of primary BC. Furthermore PTK7 expression was significantly different with respect to tumor size (ANOVA, p = 0.033 in BC and nodal involvement (ANOVA, p = 0.007 in LN. PTK7 expression in metastatic LN was related to shorter DFS (Cox Regression, p = 0.041. Our observations confirmed the transforming potential of PTK7, as well as its involvement in motility and invasivity of BC cells. PTK7 is highly expressed in TNBC cell lines. It represents a novel prognostic marker for BC patients and has potential therapeutic significance. | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 1, "mathjax_asciimath": 1, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.6988808512687683, "perplexity": 5781.1641672147225}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2017-09/segments/1487501173761.96/warc/CC-MAIN-20170219104613-00342-ip-10-171-10-108.ec2.internal.warc.gz"} |
http://mathhelpforum.com/discrete-math/177098-reflexive-symmetric-antisymmetric-transitive.html | # Math Help - reflexive, symmetric, antisymmetric, transitive?
1. ## reflexive, symmetric, antisymmetric, transitive?
For each of these binary relations, determine whether they are reflexive, symmetric,
antisymmetric, transitive. Give reasons for your answers and state whether or not they
form order relations or equivalence relations.
On the set {audi, ford, bmw, mercedes}, the relation
{(audi, audi), (audi, bmw), (bmw, bmw), (ford, ford), (mercedes,mercedes),
(audi, mercedes), (audi, ford), (bmw, ford), (mercedes, ford) }.
Let F be the set of all possible filenames consisting of character strings of at
least one character. The relation R contains all pairs of names (name1, name2)
where the first eight characters of name1 are the same as the first eight
characters of name2, or if name1 and name 2 have fewer than eight characters
and are exactly the same.
2. What have you tried so far?
3. I don't really know were to start
4. Originally Posted by jander1
I don't really know were to start
Start with the reflexive. A binary relation $R$ on a set $S$ is said to be reflexive iff $aRa$ for all $a\in S$ .
Are those relations reflexive?
5. Originally Posted by jander1
I don't really know were to start
6. Suppose the parent set is $\{a_1,a_2,a_3,a_4\}$. A relation defined on this set is reflexive if the relation-set contains the element $(a_i,a_i)$ for all $i=1,2,3,4$. Is it the case here?
A relation defined on this set is symmetric if for any $(a_i,a_j)$ belonging to the relation-set, the element $(a_j,a_i)$ is also present in the relation-set. Is it the case here for all $i,j=1,2,3,4$?
A relation defined on this set is transitive if for two elements $(a_i,a_j)$ and $(a_j,a_k)$ belonging to the relation-set, the element $(a_i,a_k)$ is also present in the relation-set. Is it the case here for all $i,j,k=1,2,3,4?$ | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 14, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.9105450510978699, "perplexity": 1286.4133803581788}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 20, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2014-42/segments/1414637905189.48/warc/CC-MAIN-20141030025825-00116-ip-10-16-133-185.ec2.internal.warc.gz"} |
https://chemistry.stackexchange.com/questions/86251/elements-which-do-not-form-oxides/86252 | # Elements which do not form oxides
I had thought that this question would be easy to answer but my searching has been unsuccessful in finding a clear answer.
For the metals, I expect that they all form oxides. Some very readily, e.g. sodium and magnesium, and some reluctantly, e.g. gold and platinum, but I cannot find a metal which does not form an oxide.
The metalloids also all appear to form oxides.
The noble gases are obvious candidates for exceptions but xenon has a known oxide. I think that it is expected for radon but I don't know whether that is confirmed. A fluoride is known for krypton but no oxide yet. No oxide is known or expected (?) for any of the lighter noble gases.
This leaves the other non-metal elements which are sufficiently few to check easily. I find no exception except for the possible pedantic case of fluorine. It forms a binary compound with oxygen but since it is more electronegative the compound is called oxygen fluoride rather than fluorine oxide.
Some elements are too radioactive to study e.g. francium and astatine but I expect that both would form oxides if we could manage to study them.
Edit: a good point that came up in the comments is oxygen itself. A pedantic exception together with fluorine.
Is that correct?
• @andselisk I may have misunderstood. Oxygen is a good answer. A subtle exception alongside fluorine. – badjohn Nov 23 '17 at 12:09
• chemistry.stackexchange.com/a/64699/9961 – Mithoron Nov 23 '17 at 15:57
• Eh, this bothers me enough that I have to ask: Should the subject read "Elements that" instead of "Elements which"? (Not a native speaker, it just looks wrong somehow) – JollyJoker Nov 23 '17 at 16:04
• @JollyJoker A good point. It's a question for a rather different stack exchange but this Oxford Dictionaries article seems to be on your side: en.oxforddictionaries.com/usage/that-or-which. It says: "This common British construction is not strictly incorrect in American English, but it is generally avoided, especially in formal writing" which may explain it. I am British, are you more familiar with US English? – badjohn Nov 23 '17 at 16:12
• @Mithoron Thank you. That's interesting though my question was not primarily about the chemistry of noble gases but more whether I had missed anything else. – badjohn Nov 23 '17 at 16:40
The first thing that came to mind is oxygen itself, as the term "oxide" suggests one other element in its chemical formula. Merriam-Webster suggests a more strict version: "a binary compound of oxygen with a more electropositive element or group". So technically pure oxygen is not an oxide.
Putting oxygen aside, helium $\ce{He}$, neon $\ce{Ne}$ and argon $\ce{Ar}$ are probably the only three conventional elements that come to mind are not yet proven to form oxides. I find it rather tricky to back up this statement properly as the lack of knowledge about an object doesn't prove its non-existence; ideally one might want to do a stability simulation at extreme pressures and temperatures to prove the existence of $\ce{(He|Ne|Ar)O_x}$ or lack thereof. There are algorithms like USPEX that are capable of that – by the way, with the help of USPEX a family of krypton oxides has been recently predicted.
• Thanks. I also considered fluorine as an exception since as you quote "a more electropositive element" whereas fluorine is more electronegative. The rule I knew was that in binary, inorganic compounds, the more electronegative element is named second. $\ce{O}\ce{F}_2$ rather than $\ce{F}_2\ce{O}$. – badjohn Nov 23 '17 at 13:40
• Yes, oxygen can by definition not form oxides. To the best of my knowledge, no compounds of helium or neon are known to date and only $\ce{HArF}$ is known for argon, but that could be dated already. – Jan Nov 23 '17 at 14:24
• " lack of knowledge about an object doesn't prove its non-existence" - of course, but I am happy with answers of the form: "no oxide of X is known". So, krypton might be in the category "no oxide known but that might change" whereas neon is "no oxide known and none expected either". – badjohn Nov 23 '17 at 14:34
So, combining all of the responses.
All metals and metalloids have known oxides.
Among the noble gases, xenon and radon have oxides, one has been predicted but not observed for krypton, and one is not expected for helium, neon, or argon.
Among the other non-metals, all have oxides except the technical exceptions of oxygen itself and fluorine; as andselisk says, an oxide is "a binary compound of oxygen with a more electropositive element or group". A binary compound of oxygen and fluorine is known but it is oxygen fluoride rather than fluorine oxide.
• Would that include astatine and francium? – Oscar Lanzi Jan 5 at 15:04
• A good point. I expect that if we could move quickly enough, we could create francium oxide and astatine oxide. The problem is the physics, I doubt that there is any chemical obstacle to these compounds. – badjohn Jan 5 at 17:09
• The intense radioactivity of all isotopes of astatine and francium would prevent collecting any macroscopic samples of any oxides, for the heat generated by radioactive decay would vaporize such samples. Wikipedia reports several empirically known compounds with astatine-oxygen bonds in solution. – Oscar Lanzi Mar 3 at 1:17 | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.5679838061332703, "perplexity": 1896.0895627734517}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 20, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2020-34/segments/1596439738816.7/warc/CC-MAIN-20200811150134-20200811180134-00051.warc.gz"} |
https://www.physicsforums.com/threads/proof-of-a-lemma-regarding-absolute-values.956746/ | Proof of a Lemma regarding absolute values
• I
• Start date
• #1
479
12
Hi all,
There's this proof that I've been trying to wrap my head around but it just doesn't seem to sink in. I've attached a screenshot below. Many thanks in advance!
Consider Case 1. There is a step that goes
$$\text{Then} \ |r| = r$$
$$Then -|r| \leq |r| \ \text{and} \ r \leq |r|$$
Why is this the case? This seems to imply that because ##|r|=r##, then ##r \leq |r|##. Is this because of the "generalisation" rule of inference that goes
$$p$$
$$\text{Therefore} \ p \vee q$$
Where ##p = |r| = r## and ##q = |r| > r##? If so, why not write ##q = |r| < r## and get a completely different result altogether?
Attachments
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607
395
The lemma says ##|r|\leq |r| ## which should be trivial.
For case 1 they already establish ##r=|r| ## so ##r\leq |r|## holds trivially. Yes, ##p\rightarrow p\lor q ## does the trick here.
You may take ##q=|r| ## and then write ##r=|r| \rightarrow r\leq |r| \lor |r|<r ##, but ##q: |r|<r## is simply not true.
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1K | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 1, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.9669201970100403, "perplexity": 8129.516133256663}, "config": {"markdown_headings": false, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2021-10/segments/1614178375274.88/warc/CC-MAIN-20210306162308-20210306192308-00546.warc.gz"} |
http://mathhelpforum.com/trigonometry/169807-range-values-question-print.html | # Range of Values Question
• January 31st 2011, 08:37 AM
cromlix
Range of Values Question
Hi there,
Can you help me with the following problem please?
If f(x) = 2 sin(3x - pi/2) + 5, what is the range of the values of f(x)?
I began by moving 5 over to the other side.
2 sin(3x - pi/2) = - 5
sin(3x - pi/2) = -5/2
Am I going in the right direction?
Thanks
Cromlix
• January 31st 2011, 08:57 AM
Ackbeet
No, I wouldn't go in that direction. I would build up the function f(x) from the simpler components using inequalities, like this:
$-1\le\sin(3x-\pi/2)\le 1$
$-2\le 2\sin(3x-\pi/2)\le 2.$
How could you finish?
• January 31st 2011, 10:18 AM
cromlix
Hi Ackbeet,
Thank you for replying: I would proceed:- -1=< sin(3x - pi/2) =< 1
-2=< sin(3x - pi/2) =< 2
$3\le\sin(3x - \pi/2)+5 \le 7.$ | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 3, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.5139805674552917, "perplexity": 7340.622938117636}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2016-30/segments/1469257824395.52/warc/CC-MAIN-20160723071024-00197-ip-10-185-27-174.ec2.internal.warc.gz"} |
http://en.wikipedia.org/wiki/Cooley%E2%80%93Tukey_FFT_algorithm | # Cooley–Tukey FFT algorithm
The Cooley–Tukey algorithm, named after J.W. Cooley and John Tukey, is the most common fast Fourier transform (FFT) algorithm. It re-expresses the discrete Fourier transform (DFT) of an arbitrary composite size N = N1N2 in terms of smaller DFTs of sizes N1 and N2, recursively, in order to reduce the computation time to O(N log N) for highly-composite N (smooth numbers). Because of the algorithm's importance, specific variants and implementation styles have become known by their own names, as described below.
Because the Cooley-Tukey algorithm breaks the DFT into smaller DFTs, it can be combined arbitrarily with any other algorithm for the DFT. For example, Rader's or Bluestein's algorithm can be used to handle large prime factors that cannot be decomposed by Cooley–Tukey, or the prime-factor algorithm can be exploited for greater efficiency in separating out relatively prime factors.
See also the fast Fourier transform for information on other FFT algorithms, specializations for real and/or symmetric data, and accuracy in the face of finite floating-point precision.
## History
This algorithm, including its recursive application, was invented around 1805 by Carl Friedrich Gauss, who used it to interpolate the trajectories of the asteroids Pallas and Juno, but his work was not widely recognized (being published only posthumously and in neo-Latin).[1][2] Gauss did not analyze the asymptotic computational time, however. Various limited forms were also rediscovered several times throughout the 19th and early 20th centuries.[2] FFTs became popular after James Cooley of IBM and John Tukey of Princeton published a paper in 1965 reinventing the algorithm and describing how to perform it conveniently on a computer.[3]
Tukey reportedly came up with the idea during a meeting of a US presidential advisory committee discussing ways to detect nuclear-weapon tests in the Soviet Union.[4][5] Another participant at that meeting, Richard Garwin of IBM, recognized the potential of the method and put Tukey in touch with Cooley, who implemented it for a different (and less-classified) problem: analyzing 3d crystallographic data (see also: multidimensional FFTs). Cooley and Tukey subsequently published their joint paper, and wide adoption quickly followed.
The fact that Gauss had described the same algorithm (albeit without analyzing its asymptotic cost) was not realized until several years after Cooley and Tukey's 1965 paper.[2] Their paper cited as inspiration only work by I. J. Good on what is now called the prime-factor FFT algorithm (PFA);[3] although Good's algorithm was initially mistakenly thought to be equivalent to the Cooley–Tukey algorithm, it was quickly realized that PFA is a quite different algorithm (only working for sizes that have relatively prime factors and relying on the Chinese Remainder Theorem, unlike the support for any composite size in Cooley–Tukey).[6]
A radix-2 decimation-in-time (DIT) FFT is the simplest and most common form of the Cooley–Tukey algorithm, although highly optimized Cooley–Tukey implementations typically use other forms of the algorithm as described below. Radix-2 DIT divides a DFT of size N into two interleaved DFTs (hence the name "radix-2") of size N/2 with each recursive stage.
The discrete Fourier transform (DFT) is defined by the formula:
$X_k = \sum_{n=0}^{N-1} x_n e^{-\frac{2\pi i}{N} nk},$
where $k$ is an integer ranging from $0$ to $N-1$.
Radix-2 DIT first computes the DFTs of the even-indexed inputs $x_{2m} \$ ($x_0, x_2, \ldots, x_{N-2}$) and of the odd-indexed inputs $x_{2m+1} \$ ($x_1, x_3, \ldots, x_{N-1}$), and then combines those two results to produce the DFT of the whole sequence. This idea can then be performed recursively to reduce the overall runtime to O(N log N). This simplified form assumes that N is a power of two; since the number of sample points N can usually be chosen freely by the application, this is often not an important restriction.
The Radix-2 DIT algorithm rearranges the DFT of the function $x_n$ into two parts: a sum over the even-numbered indices $n={2m}$ and a sum over the odd-numbered indices $n={2m+1}$:
$\begin{matrix} X_k & = & \sum \limits_{m=0}^{N/2-1} x_{2m} e^{-\frac{2\pi i}{N} (2m)k} + \sum \limits_{m=0}^{N/2-1} x_{2m+1} e^{-\frac{2\pi i}{N} (2m+1)k}. \end{matrix}$
One can factor a common multiplier $e^{-\frac{2\pi i}{N}k}$ out of the second sum, as shown in the equation below. It is then clear that the two sums are the DFT of the even-indexed part $x_{2m}$ and the DFT of odd-indexed part $x_{2m+1}$ of the function $x_n$. Denote the DFT of the Even-indexed inputs $x_{2m}$ by $E_k$ and the DFT of the Odd-indexed inputs $x_{2m + 1}$ by $O_k$ and we obtain:
$\begin{matrix} X_k= \underbrace{\sum \limits_{m=0}^{N/2-1} x_{2m} e^{-\frac{2\pi i}{N/2} mk}}_{\mathrm{DFT\;of\;even-indexed\;part\;of\;} x_m} {} + e^{-\frac{2\pi i}{N}k} \underbrace{\sum \limits_{m=0}^{N/2-1} x_{2m+1} e^{-\frac{2\pi i}{N/2} mk}}_{\mathrm{DFT\;of\;odd-indexed\;part\;of\;} x_m} = E_k + e^{-\frac{2\pi i}{N}k} O_k. \end{matrix}$
However, these smaller DFTs have a length of N/2, so we need compute only N/2 outputs: thanks to the periodicity properties of the DFT, the outputs for $N/2 \leq k < N$ from a DFT of length N/2 are identical to the outputs for $0\leq k < N/2$. That is, $E_{k + N/2} = E_k$ and $O_{k + N/2} = O_k$. The phase factor $\exp[-2\pi i k/ N]$ (called a twiddle factor) obeys the relation: $\exp[-2\pi i (k + N/2)/ N] = e^{-\pi i} \exp[-2\pi i k/ N] = -\exp[-2\pi i k/ N]$, flipping the sign of the $O_{k + N/2}$ terms. Thus, the whole DFT can be calculated as follows:
$\begin{matrix} X_k & = & \left\{ \begin{matrix} E_k + e^{-\frac{2\pi i}{N}k} O_k & \mbox{if } k < N/2 \\ \\ E_{k-N/2} - e^{-\frac{2\pi i}{N} (k-N/2)} O_{k-N/2} & \mbox{if } k \geq N/2. \end{matrix} \right. \end{matrix}$
This result, expressing the DFT of length N recursively in terms of two DFTs of size N/2, is the core of the radix-2 DIT fast Fourier transform. The algorithm gains its speed by re-using the results of intermediate computations to compute multiple DFT outputs. Note that final outputs are obtained by a +/− combination of $E_k$ and $O_k \exp(-2\pi i k/N)$, which is simply a size-2 DFT (sometimes called a butterfly in this context); when this is generalized to larger radices below, the size-2 DFT is replaced by a larger DFT (which itself can be evaluated with an FFT).
Data flow diagram for N=8: a decimation-in-time radix-2 FFT breaks a length-N DFT into two length-N/2 DFTs followed by a combining stage consisting of many size-2 DFTs called "butterfly" operations (so-called because of the shape of the data-flow diagrams).
This process is an example of the general technique of divide and conquer algorithms; in many traditional implementations, however, the explicit recursion is avoided, and instead one traverses the computational tree in breadth-first fashion.
The above re-expression of a size-N DFT as two size-N/2 DFTs is sometimes called the DanielsonLanczos lemma, since the identity was noted by those two authors in 1942[7] (influenced by Runge's 1903 work[2]). They applied their lemma in a "backwards" recursive fashion, repeatedly doubling the DFT size until the transform spectrum converged (although they apparently didn't realize the linearithmic [i.e., order N log N] asymptotic complexity they had achieved). The Danielson–Lanczos work predated widespread availability of computers and required hand calculation (possibly with mechanical aids such as adding machines); they reported a computation time of 140 minutes for a size-64 DFT operating on real inputs to 3–5 significant digits. Cooley and Tukey's 1965 paper reported a running time of 0.02 minutes for a size-2048 complex DFT on an IBM 7094 (probably in 36-bit single precision, ~8 digits).[3] Rescaling the time by the number of operations, this corresponds roughly to a speedup factor of around 800,000. (To put the time for the hand calculation in perspective, 140 minutes for size 64 corresponds to an average of at most 16 seconds per floating-point operation, around 20% of which are multiplications.)
### Pseudocode
In pseudocode, the above process could be written:[8]
X0,...,N−1 ← ditfft2(x, N, s): DFT of (x0, xs, x2s, ..., x(N-1)s):
if N = 1 then
X0 ← x0 trivial size-1 DFT base case
else
X0,...,N/2−1 ← ditfft2(x, N/2, 2s) DFT of (x0, x2s, x4s, ...)
XN/2,...,N−1 ← ditfft2(x+s, N/2, 2s) DFT of (xs, xs+2s, xs+4s, ...)
for k = 0 to N/2−1 combine DFTs of two halves into full DFT:
t ← Xk
Xk ← t + exp(−2πi k/N) Xk+N/2
Xk+N/2 ← t − exp(−2πi k/N) Xk+N/2
endfor
endif
Here, ditfft2(x,N,1), computes X=DFT(x) out-of-place by a radix-2 DIT FFT, where N is an integer power of 2 and s=1 is the stride of the input x array. x+s denotes the array starting with xs.
(The results are in the correct order in X and no further bit-reversal permutation is required; the often-mentioned necessity of a separate bit-reversal stage only arises for certain in-place algorithms, as described below.)
High-performance FFT implementations make many modifications to the implementation of such an algorithm compared to this simple pseudocode. For example, one can use a larger base case than N=1 to amortize the overhead of recursion, the twiddle factors $\exp[-2\pi i k/ N]$ can be precomputed, and larger radices are often used for cache reasons; these and other optimizations together can improve the performance by an order of magnitude or more.[8] (In many textbook implementations the depth-first recursion is eliminated entirely in favor of a nonrecursive breadth-first approach, although depth-first recursion has been argued to have better memory locality.[8][9]) Several of these ideas are described in further detail below.
## General factorizations
The basic step of the Cooley–Tukey FFT for general factorizations can be viewed as re-interpreting a 1d DFT as something like a 2d DFT. The 1d input array of length N = N1N2 is reinterpreted as a 2d N1×N2 matrix stored in column-major order. One performs smaller 1d DFTs along the N2 direction (the non-contiguous direction), then multiplies by phase factors (twiddle factors), and finally performs 1d DFTs along the N1 direction. The transposition step can be performed in the middle, as shown here, or at the beginning or end. This is done recursively for the smaller transforms.
More generally, Cooley–Tukey algorithms recursively re-express a DFT of a composite size N = N1N2 as:[10]
1. Perform N1 DFTs of size N2.
2. Multiply by complex roots of unity called twiddle factors.
3. Perform N2 DFTs of size N1.
Typically, either N1 or N2 is a small factor (not necessarily prime), called the radix (which can differ between stages of the recursion). If N1 is the radix, it is called a decimation in time (DIT) algorithm, whereas if N2 is the radix, it is decimation in frequency (DIF, also called the Sande-Tukey algorithm). The version presented above was a radix-2 DIT algorithm; in the final expression, the phase multiplying the odd transform is the twiddle factor, and the +/- combination (butterfly) of the even and odd transforms is a size-2 DFT. (The radix's small DFT is sometimes known as a butterfly, so-called because of the shape of the dataflow diagram for the radix-2 case.)
The general Cooley–Tukey factorization rewrites the indices k and n as $k = N_2 k_1 + k_2$ and $n = N_1 n_2 + n_1$, respectively, where the indices ka and na run from 0..Na-1 (for a of 1 or 2). That is, it re-indexes the input (n) and output (k) as N1 by N2 two-dimensional arrays in column-major and row-major order, respectively; the difference between these indexings is a transposition, as mentioned above. When this re-indexing is substituted into the DFT formula for nk, the $N_1 n_2 N_2 k_1$ cross term vanishes (its exponential is unity), and the remaining terms give
$X_{N_2 k_1 + k_2} = \sum_{n_1=0}^{N_1-1} \sum_{n_2=0}^{N_2-1} x_{N_1 n_2 + n_1} e^{-\frac{2\pi i}{N_1 N_2} \cdot (N_1 n_2 + n_1) \cdot (N_2 k_1 + k_2) }$
$= \sum_{n_1=0}^{N_1-1} \left[ e^{-\frac{2\pi i}{N} n_1 k_2 } \right] \left( \sum_{n_2=0}^{N_2-1} x_{N_1 n_2 + n_1} e^{-\frac{2\pi i}{N_2} n_2 k_2 } \right) e^{-\frac{2\pi i}{N_1} n_1 k_1 }$
where each inner sum is a DFT of size N2, each outer sum is a DFT of size N1, and the [...] bracketed term is the twiddle factor.
## Data reordering, bit reversal, and in-place algorithms
Although the abstract Cooley–Tukey factorization of the DFT, above, applies in some form to all implementations of the algorithm, much greater diversity exists in the techniques for ordering and accessing the data at each stage of the FFT. Of special interest is the problem of devising an in-place algorithm that overwrites its input with its output data using only O(1) auxiliary storage.
The most well-known reordering technique involves explicit bit reversal for in-place radix-2 algorithms. Bit reversal is the permutation where the data at an index n, written in binary with digits b4b3b2b1b0 (e.g. 5 digits for N=32 inputs), is transferred to the index with reversed digits b0b1b2b3b4 . Consider the last stage of a radix-2 DIT algorithm like the one presented above, where the output is written in-place over the input: when $E_k$ and $O_k$ are combined with a size-2 DFT, those two values are overwritten by the outputs. However, the two output values should go in the first and second halves of the output array, corresponding to the most significant bit b4 (for N=32); whereas the two inputs $E_k$ and $O_k$ are interleaved in the even and odd elements, corresponding to the least significant bit b0. Thus, in order to get the output in the correct place, these two bits must be swapped. If you include all of the recursive stages of a radix-2 DIT algorithm, all the bits must be swapped and thus one must pre-process the input (or post-process the output) with a bit reversal to get in-order output. (If each size-N/2 subtransform is to operate on contiguous data, the DIT input is pre-processed by bit-reversal.) Correspondingly, if you perform all of the steps in reverse order, you obtain a radix-2 DIF algorithm with bit reversal in post-processing (or pre-processing, respectively). Alternatively, some applications (such as convolution) work equally well on bit-reversed data, so one can perform forward transforms, processing, and then inverse transforms all without bit reversal to produce final results in the natural order.
Many FFT users, however, prefer natural-order outputs, and a separate, explicit bit-reversal stage can have a non-negligible impact on the computation time,[13] even though bit reversal can be done in O(N) time and has been the subject of much research.[18][19][20] Also, while the permutation is a bit reversal in the radix-2 case, it is more generally an arbitrary (mixed-base) digit reversal for the mixed-radix case, and the permutation algorithms become more complicated to implement. Moreover, it is desirable on many hardware architectures to re-order intermediate stages of the FFT algorithm so that they operate on consecutive (or at least more localized) data elements. To these ends, a number of alternative implementation schemes have been devised for the Cooley–Tukey algorithm that do not require separate bit reversal and/or involve additional permutations at intermediate stages.
The problem is greatly simplified if it is out-of-place: the output array is distinct from the input array or, equivalently, an equal-size auxiliary array is available. The Stockham auto-sort algorithm[21][22] performs every stage of the FFT out-of-place, typically writing back and forth between two arrays, transposing one "digit" of the indices with each stage, and has been especially popular on SIMD architectures.[22][23] Even greater potential SIMD advantages (more consecutive accesses) have been proposed for the Pease algorithm,[24] which also reorders out-of-place with each stage, but this method requires separate bit/digit reversal and O(N log N) storage. One can also directly apply the Cooley–Tukey factorization definition with explicit (depth-first) recursion and small radices, which produces natural-order out-of-place output with no separate permutation step (as in the pseudocode above) and can be argued to have cache-oblivious locality benefits on systems with hierarchical memory.[9][13][25]
A typical strategy for in-place algorithms without auxiliary storage and without separate digit-reversal passes involves small matrix transpositions (which swap individual pairs of digits) at intermediate stages, which can be combined with the radix butterflies to reduce the number of passes over the data.[13][26][27][28][29]
## References
1. ^ Gauss, Carl Friedrich, "Theoria interpolationis methodo nova tractata", Werke, Band 3, 265–327 (Königliche Gesellschaft der Wissenschaften, Göttingen, 1866)
2. Heideman, M. T., D. H. Johnson, and C. S. Burrus, "Gauss and the history of the fast Fourier transform," IEEE ASSP Magazine, 1, (4), 14–21 (1984)
3. Cooley, James W.; Tukey, John W. (1965). "An algorithm for the machine calculation of complex Fourier series". Math. Comput. 19: 297–301. doi:10.2307/2003354.
4. ^ Cooley, James W.; Lewis, Peter A. W.; Welch, Peter D. (1967). "Historical notes on the fast Fourier transform". IEEE Trans. on Audio and Electroacoustics 15 (2): 76–79.
5. ^ Rockmore, Daniel N. , Comput. Sci. Eng. 2 (1), 60 (2000). The FFT — an algorithm the whole family can use Special issue on "top ten algorithms of the century "[1]
6. ^ James W. Cooley, Peter A. W. Lewis, and Peter W. Welch, "Historical notes on the fast Fourier transform," Proc. IEEE, vol. 55 (no. 10), p. 1675–1677 (1967).
7. ^ Danielson, G. C., and C. Lanczos, "Some improvements in practical Fourier analysis and their application to X-ray scattering from liquids," J. Franklin Inst. 233, 365–380 and 435–452 (1942).
8. ^ a b c S. G. Johnson and M. Frigo, “Implementing FFTs in practice,” in Fast Fourier Transforms (C. S. Burrus, ed.), ch. 11, Rice University, Houston TX: Connexions, September 2008.
9. ^ a b Singleton, Richard C. (1967). "On computing the fast Fourier transform". Commun. of the ACM 10 (10): 647–654. doi:10.1145/363717.363771.
10. ^ a b Duhamel, P., and M. Vetterli, "Fast Fourier transforms: a tutorial review and a state of the art," Signal Processing 19, 259–299 (1990)
11. ^ Lundy, T., and J. Van Buskirk, "A new matrix approach to real FFTs and convolutions of length 2k," Computing 80, 23-45 (2007).
12. ^ Johnson, S. G., and M. Frigo, "A modified split-radix FFT with fewer arithmetic operations," IEEE Trans. Signal Processing 55 (1), 111–119 (2007).
13. Frigo, M.; Johnson, S. G. (2005). "The Design and Implementation of FFTW3". Proceedings of the IEEE 93 (2): 216–231. doi:10.1109/JPROC.2004.840301.
14. ^ a b Gentleman W. M., and G. Sande, "Fast Fourier transforms—for fun and profit," Proc. AFIPS 29, 563–578 (1966).
15. ^ a b Bailey, David H., "FFTs in external or hierarchical memory," J. Supercomputing 4 (1), 23–35 (1990)
16. ^ a b M. Frigo, C.E. Leiserson, H. Prokop, and S. Ramachandran. Cache-oblivious algorithms. In Proceedings of the 40th IEEE Symposium on Foundations of Computer Science (FOCS 99), p.285-297. 1999. Extended abstract at IEEE, at Citeseer.
17. ^ Cooley, J. W., P. Lewis and P. Welch, "The Fast Fourier Transform and its Applications", IEEE Trans on Education 12, 1, 28-34 (1969)
18. ^ Karp, Alan H. (1996). "Bit reversal on uniprocessors". SIAM Review 38 (1): 1–26. doi:10.1137/1038001. JSTOR 2132972.
19. ^ Carter, Larry; Gatlin, Kang Su (1998). "Towards an optimal bit-reversal permutation program". Proc. 39th Ann. Symp. on Found. of Comp. Sci. (FOCS): 544–553. doi:10.1109/SFCS.1998.743505.
20. ^ Rubio, M.; Gómez, P.; Drouiche, K. (2002). "A new superfast bit reversal algorithm". Intl. J. Adaptive Control and Signal Processing 16 (10): 703–707. doi:10.1002/acs.718.
21. ^ Originally attributed to Stockham in W. T. Cochran et al., What is the fast Fourier transform?, Proc. IEEE vol. 55, 1664–1674 (1967).
22. ^ a b P. N. Swarztrauber, FFT algorithms for vector computers, Parallel Computing vol. 1, 45–63 (1984).
23. ^ Swarztrauber, P. N. (1982). "Vectorizing the FFTs". In Rodrigue, G. Parallel Computations. New York: Academic Press. pp. 51–83. ISBN 0-12-592101-2.
24. ^ Pease, M. C. (1968). "An adaptation of the fast Fourier transform for parallel processing". J. ACM 15 (2): 252–264. doi:10.1145/321450.321457.
25. ^ Frigo, Matteo; Johnson, Steven G. "FFTW". A free (GPL) C library for computing discrete Fourier transforms in one or more dimensions, of arbitrary size, using the Cooley–Tukey algorithm
26. ^ Johnson, H. W.; Burrus, C. S. (1984). "An in-place in-order radix-2 FFT". Proc. ICASSP: 28A.2.1–28A.2.4.
27. ^ Temperton, C. (1991). "Self-sorting in-place fast Fourier transform". SIAM Journal on Scientific and Statistical Computing 12 (4): 808–823. doi:10.1137/0912043.
28. ^ Qian, Z.; Lu, C.; An, M.; Tolimieri, R. (1994). "Self-sorting in-place FFT algorithm with minimum working space". IEEE Trans. ASSP 52 (10): 2835–2836. doi:10.1109/78.324749.
29. ^ Hegland, M. (1994). "A self-sorting in-place fast Fourier transform algorithm suitable for vector and parallel processing". Numerische Mathematik 68 (4): 507–547. doi:10.1007/s002110050074. | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 1, "img_math": 41, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.8585857152938843, "perplexity": 2696.9096423870196}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2013-20/segments/1368710313659/warc/CC-MAIN-20130516131833-00089-ip-10-60-113-184.ec2.internal.warc.gz"} |
http://physics.stackexchange.com/questions/35383/what-is-the-origin-of-the-many-body-expansion | # What is the origin of the many-body expansion?
I'm looking for the original introduction of the many-body expansion (MBE) in the scientific literature. More specifically, I'm interested in a theoretical justification of the rapid convergence of the expansion, especially in the context of molecular physics. The MBE is often introduced in scientific papers without referring to foregoing work that introduces the concept. Instead, one often states something like: "Following the well-known many-body expansion, one writes ...". See for example http://pubs.acs.org/doi/abs/10.1021/ct600253j. (freely available at http://t1.chem.umn.edu/Truhlar/docs/758FAV.pdf)
The many-body expansion is a scheme to decompose the energy of a general system of $N$ particles as follows:
$$V = \sum_{i = 1}^N V_i$$
with
$$V_1 = \sum_{i=1}^N E_i$$
$$V_2 = \sum_{i=1}^N \sum_{j=i+1}^N E_{ij} - E_i - E_j$$
$$V_3 = \sum_{i=1}^N \sum_{j=i+1}^N \sum_{k=j+1}^N \biggl( (E_{ijk} - E_i - E_j - E_k) - (E_{ij} - E_i - E_j)\\ - (E_{jk} - E_j - E_k) - (E_{ki} - E_k - E_i)\biggr)$$
and so on. In these equations, $E_i$ is the energy consisting only of particle $i$, $E_{ij}$ is the energy of a system containing only particles $i$ and $j$, $E_{ijk}$ is the energy of a system with three partilces, $i$, $j$ and $k$, and so on.
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There is some justification of convergence speed based on perturbative expansion of intermolecular interaction combined with multipole expansion. E.g. the Axilrod–Teller potential in three-body interaction goes like $R^{-9}$, while London potential goes like $R^{-6}$. – user26143 Jul 21 '14 at 9:46 | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 1, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.9588510990142822, "perplexity": 495.6369614025208}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2015-32/segments/1438042988061.16/warc/CC-MAIN-20150728002308-00032-ip-10-236-191-2.ec2.internal.warc.gz"} |
http://physics.stackexchange.com/questions/64371/mathematical-equivalence-between-li%c3%a9nard-wiechert-potential-and-4-potential-in-r | # Mathematical equivalence between Liénard-Wiechert potential and 4-potential in Rindler coordinates
I'm studying the problem of the radiation of an uniformly accelerated point charge:
$$x^{\mu}(\lambda)\to(g^{-1}\sinh g\lambda,0,0,g^{-1}\cosh g\lambda)$$
I found that when a point charge is moving along the $z$ axis with a constant acceleration $g$, the components of the 4-potential can be found using Rindler coordinates:
$$z=Z\cosh g\tau, \qquad t=Z\sinh g\tau \qquad \mathrm{I}$$ $$z=Z\sinh g\tau, \qquad t=Z\cosh g\tau \qquad \mathrm{II}$$ $$z=-Z\cosh g\tau, \qquad t=-Z\sinh g\tau \qquad \mathrm{III}$$ $$z=-Z\sinh g\tau, \qquad t=-Z\cosh g\tau \qquad \mathrm{IV}$$
with the metric
$$ds^{2}=\epsilon(-g^{2}Z{}^{2}\, d\tau^{2}+dZ^{2})+dx^{2}+dy^{2}$$
where $\epsilon=+1$ in regions I and III, and $\epsilon=-1$ in regions II and IV. And the numbers indicate the space-time region:
Now, I understand that the potentials obtained with the Rindler coordinates must be equivalent to the Liénard-Wiechert potential, because the change of coordinates (Minkowski->Rindler) is equivalent to change from an inertial frame of reference to an accelerated one. The problem is, the article
Radiation from a uniformly accelerated charge. D G Boulware. Ann. Phys. 124 no.1 (1980), pp. 169–188. Available on CiteSeerX
finds that the components of the 4-potential (Rindler coordinates) are:
$$A_{\tau}=-\frac{eg}{4\pi}\frac{\epsilon Z^{2}+\rho^{2}+g^{-2}}{\left[\left(\epsilon Z^{2}+\rho^{2}+g^{-2}\right)^{2}-4 \epsilon Z^{2}g^{-2}\right]^{1/2}}$$
where $\rho^{2}:=x^{2}+y^{2}$. $A_x=A_y=0$, and
$$A_{Z}=-\frac{e}{4\pi Z}$$
In regions I and II.
My question is: How can I conclude that this components are actually equivalent to the components of the Liénard-Wiechert potential?
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Any GR textbook would give you a full set of rules to perform coordinate tramsforms on motions, fields, potentials, and Maxwell's equations. Then it is just a long simple calculation. And remember, finally you can get something that differs from the sought potential by a pure gauge summand. – firtree May 13 '13 at 5:28
@firtree Oh, I think I get it. In this case I must transform the Liénard-Wiechert potential using Rindler change of coordinates and I should obtain the $A_\tau$ and $A_Z$, right? – Anuar May 13 '13 at 15:26
Yes but first you should get the Liénard-Wiechert potential for this particular motion of charge. – firtree May 13 '13 at 15:39
(Please don't forget @firtree or I'm not notified.) Yes it is possible to consider the charge in the accelerated frame as one uniformly moving (or just stationary) but that does not simplify the work. Now gravitation is present, and the Coulomb's law doesn't hold true! Field lines become "heavy" and "drooping", and finally you have to solve Maxwell's equations for the curved space-time (can be found in your GR textbook) - which is more intricate than the use of the known Liénard-Wiechert potential which is already a solution. Be warned :-) – firtree May 13 '13 at 16:28
It is not the familiar Coulomb field, actually. It is some different field, though static as well. It is close to the Coulomb field in the close neighborhood of the charge, but the gravitation changes it in the farther regions. You can plot it by some software to get convinced. And, $\mathbf{E}$ is a gauge-independent vector, so no gauge choice could change it. – firtree Jun 4 '13 at 22:48 | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 1, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.870232343673706, "perplexity": 629.9811833212249}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2015-18/segments/1429246658116.80/warc/CC-MAIN-20150417045738-00131-ip-10-235-10-82.ec2.internal.warc.gz"} |
https://arxiv.org/abs/0905.4302?context=astro-ph | astro-ph
# Title:Absolute electron and positron fluxes from PAMELA/Fermi and Dark Matter
Abstract: We extract the positron and electron fluxes in the energy range 10 - 100 GeV by combining the recent data from PAMELA and Fermi LAT. The {\it absolute positron and electron} fluxes thus obtained are found to obey the power laws: $E^{-2.65}$ and $E^{-3.06}$ respectively, which can be confirmed by the upcoming data from PAMELA. The positron flux appears to indicate an excess at energies $E\gsim 50$ GeV even if the uncertainty in the secondary positron flux is added to the Galactic positron background. This leaves enough motivation for considering new physics, such as annihilation or decay of dark matter, as the origin of positron excess in the cosmic rays.
Comments: Accepted by JCAP Subjects: High Energy Physics - Phenomenology (hep-ph); High Energy Astrophysical Phenomena (astro-ph.HE); General Relativity and Quantum Cosmology (gr-qc) Journal reference: JCAP 0907:039,2009 DOI: 10.1088/1475-7516/2009/07/039 Cite as: arXiv:0905.4302 [hep-ph] (or arXiv:0905.4302v3 [hep-ph] for this version)
## Submission history
From: Narendra Sahu [view email]
[v1] Wed, 27 May 2009 15:56:34 UTC (67 KB)
[v2] Thu, 28 May 2009 19:05:18 UTC (68 KB)
[v3] Tue, 7 Jul 2009 19:04:00 UTC (68 KB) | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.7818830013275146, "perplexity": 4404.719948049113}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 20, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2019-43/segments/1570986684425.36/warc/CC-MAIN-20191018181458-20191018204958-00244.warc.gz"} |
http://careyoukeep.com/brain-cognitive-supplements-drugs-and-the-brain.html | Tuesday: I went to bed at 1am, and first woke up at 6am, and I wrote down a dream; the lucid dreaming book I was reading advised that waking up in the morning and then going back for a short nap often causes lucid dreams, so I tried that - and wound up waking up at 10am with no dreams at all. Oops. I take a pill, but the whole day I don’t feel so hot, although my conversation and arguments seem as cogent as ever. I’m also having a terrible time focusing on any actual work. At 8 I take another; I’m behind on too many things, and it looks like I need an all-nighter to catch up. The dose is no good; at 11, I still feel like at 8, possibly worse, and I take another along with the choline+piracetam (which makes a total of 600mg for the day). Come 12:30, and I disconsolately note that I don’t seem any better, although I still seem to understand the IQ essays I am reading. I wonder if this is tolerance to modafinil, or perhaps sleep catching up to me? Possibly it’s just that I don’t remember what the quasi-light-headedness of modafinil felt like. I feel this sort of zombie-like state without change to 4am, so it must be doing something, when I give up and go to bed, getting up at 7:30 without too much trouble. Some N-backing at 9am gives me some low scores but also some pretty high scores (38/43/66/40/24/67/60/71/54 or ▂▂▆▂▁▆▅▇▄), which suggests I can perform normally if I concentrate. I take another pill and am fine the rest of the day, going to bed at 1am as usual.
One of the most popular legal stimulants in the world, nicotine is often conflated with the harmful effects of tobacco; considered on its own, it has performance & possibly health benefits. Nicotine is widely available at moderate prices as long-acting nicotine patches, gums, lozenges, and suspended in water for vaping. While intended for smoking cessation, there is no reason one cannot use a nicotine patch or nicotine gum for its stimulant effects.
###### Another classic approach to the assessment of working memory is the span task, in which a series of items is presented to the subject for repetition, transcription, or recognition. The longest series that can be reproduced accurately is called the forward span and is a measure of working memory capacity. The ability to reproduce the series in reverse order is tested in backward span tasks and is a more stringent test of working memory capacity and perhaps other working memory functions as well. The digit span task from the Wechsler (1981) IQ test was used in four studies of stimulant effects on working memory. One study showed that d-AMP increased digit span (de Wit et al., 2002), and three found no effects of d-AMP or MPH (Oken, Kishiyama, & Salinsky, 1995; Schmedtje, Oman, Letz, & Baker, 1988; Silber, Croft, Papafotiou, & Stough, 2006). A spatial span task, in which subjects must retain and reproduce the order in which boxes in a scattered spatial arrangement change color, was used by Elliott et al. (1997) to assess the effects of MPH on working memory. For subjects in the group receiving placebo first, MPH increased spatial span. However, for the subjects who received MPH first, there was a nonsignificant opposite trend. The group difference in drug effect is not easily explained. The authors noted that the subjects in the first group performed at an overall lower level, and so, this may be another manifestation of the trend for a larger enhancement effect for less able subjects.
Organizations, and even entire countries, are struggling with “always working” cultures. Germany and France have adopted rules to stop employees from reading and responding to email after work hours. Several companies have explored banning after-hours email; when one Italian company banned all email for one week, stress levels dropped among employees. This is not a great surprise: A Gallup study found that among those who frequently check email after working hours, about half report having a lot of stress.
“I enjoyed this book. It was full of practical information. It was easy to understand. I implemented some of the ideas in the book and they have made a positive impact for me. Not only is this book a wealth of knowledge it helps you think outside the box and piece together other ideas to research and helps you understand more about TBI and the way food might help you mitigate symptoms.”
So I eventually got around to ordering another thing of nicotine gum, Habitrol Nicotine Gum, 4mg MINT flavor COATED gum. 96 pieces per box. Gum should be easier to double-blind myself with than nicotine patches - just buy some mint gum. If 4mg is too much, cut the gum in half or whatever. When it arrived, my hopes were borne out: the gum was rectangular and soft, which made it easy to cut into fourths.
More recently, the drug modafinil (brand name: Provigil) has become the brain-booster of choice for a growing number of Americans. According to the FDA, modafinil is intended to bolster “wakefulness” in people with narcolepsy, obstructive sleep apnea or shift work disorder. But when people without those conditions take it, it has been linked with improvements in alertness, energy, focus and decision-making. A 2017 study found evidence that modafinil may enhance some aspects of brain connectivity, which could explain these benefits.
A record of nootropics I have tried, with thoughts about which ones worked and did not work for me. These anecdotes should be considered only as anecdotes, and one’s efforts with nootropics a hobby to put only limited amounts of time into due to the inherent limits of drugs as a force-multiplier compared to other things like programming1; for an ironic counterpoint, I suggest the reader listen to a video of Jonathan Coulton’s I Feel Fantastic while reading.
Took pill 12:11 PM. I am not certain. While I do get some things accomplished (a fair amount of work on the Silk Road article and its submission to places), I also have some difficulty reading through a fiction book (Sum) and I seem kind of twitchy and constantly shifting windows. I am weakly inclined to think this is Adderall (say, 60%). It’s not my normal feeling. Next morning - it was Adderall.
It is at the top of the supplement snake oil list thanks to tons of correlations; for a review, see Luchtman & Song 2013 but some specifics include Teenage Boys Who Eat Fish At Least Once A Week Achieve Higher Intelligence Scores, anti-inflammatory properties (see Fish Oil: What the Prescriber Needs to Know on arthritis), and others - Fish oil can head off first psychotic episodes (study; Seth Roberts commentary), Fish Oil May Fight Breast Cancer, Fatty Fish May Cut Prostate Cancer Risk & Walnuts slow prostate cancer, Benefits of omega-3 fatty acids tally up, Serum Phospholipid Docosahexaenonic Acid Is Associated with Cognitive Functioning during Middle Adulthood endless anecdotes.
As mentioned earlier, cognitive control is needed not only for inhibiting actions, but also for shifting from one kind of action or mental set to another. The WCST taxes cognitive control by requiring the subject to shift from sorting cards by one dimension (e.g., shape) to another (e.g., color); failures of cognitive control in this task are manifest as perseverative errors in which subjects continue sorting by the previously successful dimension. Three studies included the WCST in their investigations of the effects of d-AMP on cognition (Fleming et al., 1995; Mattay et al., 1996, 2003), and none revealed overall effects of facilitation. However, Mattay et al. (2003) subdivided their subjects according to COMT genotype and found differences in both placebo performance and effects of the drug. Subjects who were homozygous for the val allele (associated with lower prefrontal dopamine activity) made more perseverative errors on placebo than other subjects and improved significantly with d-AMP. Subjects who were homozygous for the met allele performed best on placebo and made more errors on d-AMP.
One curious thing that leaps out looking at the graphs is that the estimated underlying standard deviations differ: the nicotine days have a strikingly large standard deviation, indicating greater variability in scores - both higher and lower, since the means weren’t very different. The difference in standard deviations is just 6.6% below 0, so the difference almost reaches our usual frequentist levels of confidence too, which we can verify by testing:
But how to blind myself? I used my pill maker to make 9 OO pills of piracetam mix, and then 9 OO pills of piracetam mix+the Adderall, then I put them in a baggy. The idea is that I can blind myself as to what pill I am taking that day since at the end of the day, I can just look in the baggy and see whether a placebo or Adderall pill is missing: the big capsules are transparent so I can see whether there is a crushed-up blue Adderall in the end or not. If there are fewer Adderall than placebo, I took an Adderall, and vice-versa. Now, since I am checking at the end of each day, I also need to remove or add the opposite pill to maintain the ratio and make it easy to check the next day; more importantly I need to replace or remove a pill, because otherwise the odds will be skewed and I will know how they are skewed. (Imagine I started with 4 Adderalls and 4 placebos, and then 3 days in a row I draw placebos but I don’t add or remove any pills; the next day, because most of the placebos have been used up, there’s only a small chance I will get a placebo…)
“Cavin’s personal experience and humble writing to help educate, not only people who have suffered brain injuries, but anyone interested in the best nutritional advice for optimum brain function is a great introduction to proper nutrition filled with many recommendations of how you can make a changes to your diet immediately. This book provides amazing personal insight related to Cavin’s recovery accompanied with well cited peer reviewed sources throughout the entire book detailing the most recent findings around functional neurology!
Clarke and Sokoloff (1998) remarked that although [a] common view equates concentrated mental effort with mental work…there appears to be no increased energy utilization by the brain during such processes (p. 664), and …the areas that participate in the processes of such reasoning represent too small a fraction of the brain for changes in their functional and metabolic activities to be reflected in the energy metabolism of the brain… (p. 675).
By the end of 2009, at least 25 studies reported surveys of college students’ rates of nonmedical stimulant use. Of the studies using relatively smaller samples, prevalence was, in chronological order, 16.6% (lifetime; Babcock & Byrne, 2000), 35.3% (past year; Low & Gendaszek, 2002), 13.7% (lifetime; Hall, Irwin, Bowman, Frankenberger, & Jewett, 2005), 9.2% (lifetime; Carroll, McLaughlin, & Blake, 2006), and 55% (lifetime, fraternity students only; DeSantis, Noar, & Web, 2009). Of the studies using samples of more than a thousand students, somewhat lower rates of nonmedical stimulant use were found, although the range extends into the same high rates as the small studies: 2.5% (past year, Ritalin only; Teter, McCabe, Boyd, & Guthrie, 2003), 5.4% (past year; McCabe & Boyd, 2005), 4.1% (past year; McCabe, Knight, Teter, & Wechsler, 2005), 11.2% (past year; Shillington, Reed, Lange, Clapp, & Henry, 2006), 5.9% (past year; Teter, McCabe, LaGrange, Cranford, & Boyd, 2006), 16.2% (lifetime; White, Becker-Blease, & Grace-Bishop, 2006), 1.7% (past month; Kaloyanides, McCabe, Cranford, & Teter, 2007), 10.8% (past year; Arria, O’Grady, Caldeira, Vincent, & Wish, 2008); 5.3% (MPH only, lifetime; Du-Pont, Coleman, Bucher, & Wilford, 2008); 34% (lifetime; DeSantis, Webb, & Noar, 2008), 8.9% (lifetime; Rabiner et al., 2009), and 7.5% (past month; Weyandt et al., 2009).
When Giurgea coined the word nootropic (combining the Greek words for mind and bending) in the 1970s, he was focused on a drug he had synthesized called piracetam. Although it is approved in many countries, it isn’t categorized as a prescription drug in the United States. That means it can be purchased online, along with a number of newer formulations in the same drug family (including aniracetam, phenylpiracetam, and oxiracetam). Some studies have shown beneficial effects, including one in the 1990s that indicated possible improvement in the hippocampal membranes in Alzheimer’s patients. But long-term studies haven’t yet borne out the hype.
# P.S. Even though Thrive Natural’s Super Brain Renew is the best brain and memory supplement we have found, we would still love to hear about other Brain and Memory Supplements that you have tried! If you have had a great experience with a memory supplement that we did not cover in this article, let us know! E-mail me at : [email protected] We’ll check it out for you and if it looks good, we’ll post it on our site!
Since coffee drinking may lead to a worsening of calcium balance in humans, we studied the serial changes of serum calcium, PTH, 1,25-dihydroxyvitamin D (1,25(OH)2D) vitamin D and calcium balance in young and adult rats after daily administration of caffeine for 4 weeks. In the young rats, there was an increase in urinary calcium and endogenous fecal calcium excretion after four days of caffeine administration that persisted for the duration of the experiment. Serum calcium decreased on the fourth day of caffeine administration and then returned to control levels. In contrast, the serum PTH and 1,25(OH)2D remained unchanged initially, but increased after 2 weeks of caffeine administration…In the adult rat group, an increase in the urinary calcium and endogenous fecal calcium excretion and serum levels of PTH was found after caffeine administration. However, the serum 1,25(OH)2D levels and intestinal absorption coefficient of calcium remained the same as in the adult control group.
I started with the 10g of Vitality Enhanced Blend, a sort of tan dust. Used 2 little-spoonfuls (dust tastes a fair bit like green/oolong tea dust) into the tea mug and then some boiling water. A minute of steeping and… bleh. Tastes sort of musty and sour. (I see why people recommended sweetening it with honey.) The effects? While I might’ve been more motivated - I hadn’t had caffeine that day and was a tad under the weather, a feeling which seemed to go away perhaps half an hour after starting - I can’t say I experienced any nausea or very noticeable effects. (At least the flavor is no longer quite so offensive.)
along with the previous bit of globalization is an important factor: shipping is ridiculously cheap. The most expensive S&H in my modafinil price table is ~$15 (and most are international). To put this in perspective, I remember in the 90s you could easily pay$15 for domestic S&H when you ordered online - but it’s 2013, and the dollar has lost at least half its value, so in real terms, ordering from abroad may be like a quarter of what it used to cost, which makes a big difference to people dipping their toes in and contemplating a small order to try out this ’nootropics thing they’ve heard about.
Methylphenidate, commonly known as Ritalin, is a stimulant first synthesised in the 1940s. More accurately, it’s a psychostimulant - often prescribed for ADHD - that is intended as a drug to help focus and concentration. It also reduces fatigue and (potentially) enhances cognition. Similar to Modafinil, Ritalin is believed to reduce dissipation of dopamine to help focus. Ritalin is a Class B drug in the UK, and possession without a prescription can result in a 5 year prison sentence. Please note: Side Effects Possible. See this article for more on Ritalin.
Kratom (Erowid, Reddit) is a tree leaf from Southeast Asia; it’s addictive to some degree (like caffeine and nicotine), and so it is regulated/banned in Thailand, Malaysia, Myanmar, and Bhutan among others - but not the USA. (One might think that kratom’s common use there indicates how very addictive it must be, except it literally grows on trees so it can’t be too hard to get.) Kratom is not particularly well-studied (and what has been studied is not necessarily relevant - I’m not addicted to any opiates!), and it suffers the usual herbal problem of being an endlessly variable food product and not a specific chemical with the fun risks of perhaps being poisonous, but in my reading it doesn’t seem to be particularly dangerous or have serious side-effects.
So the chi-squared believes there is a statistically-significant difference, the two-sample test disagrees, and the binomial also disagrees. Since I regarded it as a dubious theory, can’t see a difference, and the binomial seems like the most appropriate test, I conclude that several months of 1mg iodine did not change my eye color. (As a final test, when I posted the results on the Longecity forum where people were claiming the eye color change, I swapped the labels on the photos to see if anyone would claim something along the lines when I look at the photos, I can see a difference!. I thought someone might do that, which would be a damning demonstration of their biases & wishful thinking, but no one did.)
This calculation - reaping only \frac{7}{9} of the naive expectation - gives one pause. How serious is the sleep rebound? In another article, I point to a mice study that sleep deficits can take 28 days to repay. What if the gain from modafinil is entirely wiped out by repayment and all it did was defer sleep? Would that render modafinil a waste of money? Perhaps. Thinking on it, I believe deferring sleep is of some value, but I cannot decide whether it is a net profit.
“You know how they say that we can only access 20% of our brain?” says the man who offers stressed-out writer Eddie Morra a fateful pill in the 2011 film Limitless. “Well, what this does, it lets you access all of it.” Morra is instantly transformed into a superhuman by the fictitious drug NZT-48. Granted access to all cognitive areas, he learns to play the piano in three days, finishes writing his book in four, and swiftly makes himself a millionaire.
Piracetam is a reliable supplement for improving creativity. It is an entry level racetam due to its lack of severe side effects and relative subtlety. Piracetam’s effects take hold over time through continual use. There is less instant gratification compared to other brain enhancers. Additionally, this nootropic can enhance holistic thinking, verbal memory, and mental energy levels.
I’m wary of others, though. The trouble with using a blanket term like “nootropics” is that you lump all kinds of substances in together. Technically, you could argue that caffeine and cocaine are both nootropics, but they’re hardly equal. With so many ways to enhance your brain function, many of which have significant risks, it’s most valuable to look at nootropics on a case-by-case basis. Here’s a list of 9 nootropics, along with my thoughts on each. | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 0, "mathjax_asciimath": 1, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.3476394712924957, "perplexity": 3487.922581484092}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2019-18/segments/1555578732961.78/warc/CC-MAIN-20190425173951-20190425195951-00502.warc.gz"} |
https://brilliant.org/problems/an-algebra-problem-by-sakanksha-deo/ | # An algebra problem by Sakanksha Deo
Algebra Level 3
For $$x^{2}+ 2x + 5$$ to be a factor of $$x^{4 }+ p x^ {2} + q$$ , the value of p and q should respectively be:
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https://homework.zookal.com/questions-and-answers/it-is-known-from-past-years-that-the-average-iq-347625483 | 1. Math
2. Statistics And Probability
3. it is known from past years that the average iq...
# Question: it is known from past years that the average iq...
###### Question details
It is known from past years that the average IQ of Commack elementary students is at least 110. The principal thinks that this is an overestimate, and that the average IQ of students here is less than 110. The principal administers an IQ test to 20 randomly selected students. Among the sampled students, the average IQ is 104 with a standard deviation of 10. Assume a significance level of 0.05 and conduct a hypothesis test. | {"extraction_info": {"found_math": false, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.9765722155570984, "perplexity": 640.0236552286331}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.3, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2021-21/segments/1620243989012.26/warc/CC-MAIN-20210509183309-20210509213309-00445.warc.gz"} |
http://mathoverflow.net/questions/44734/when-does-a-mother-wavelet-generate-a-frame?answertab=active | # When does a mother wavelet generate a frame?
This question is about conditions on a mother wavelet that generates a countable familily of child wavelets via scaling and translation, that are both necessary and sufficient for the child wavelets to form a frame in the Hilbert space $L^2(\mathbb{R})$
Here are the precise definitions of these concepts in the context of this question:
Let a mother wavelet be an element $\psi \in L^2({\mathbb{R}})$ with $\|\psi\| = 1$ and a finite admissibility constant $0 \lt C_{\psi} \lt \infty$ that is defined as follows: $$C_{\psi} = \int_{- \infty}^{\infty} \frac{| \hat{\psi} (\omega) |^2}{|\omega|} d\omega$$ where $\hat{\psi}$ denotes the Fourier transform of $\psi$.
Let $\psi$ be such a mother wavelet and define the countable set of child wavelets $W$ as follows: Let $\sigma \gt 1, \tau \gt 0$ be real numbers and
$$W := \{ \psi_{j, k}: j, k \in \mathbb{Z}, \psi_{j, k}(t) = \frac{1}{\sigma^{- \frac{j}{2}}} \psi(\frac{t - k \tau \sigma^{-j}}{\sigma^{-j}}) \}$$
Now let a frame in a separable Hilbert space be a countable set of vectors $\{ \phi_j \}$ such that there are constants $a, b \gt 0$ such that for every vector $f$ we have
$$a \|f\|^2 \le \sum_j | \langle f, \phi_j \rangle |^2 \le b \|f\|^2$$
My question is: Are there conditions known on the triple $(\psi, \sigma, \tau)$ that are both necessary and sufficient for W, the set of child wavelets, to be a frame in $L^2(\mathbb{R})$?
(AFAIK there are conditions that are necessary, and other conditions that are sufficient, known since Ingrid Daubechies published her results in 1990. But there don't seem to be any conditions that are both necessary and sufficient.)
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add comment
## 1 Answer
No. This question is, I believe, open even for functions of the type $\hat \psi = I_E$, dilations by powers of 2 and translation by integers. See, for example the relatively recent paper of Bownik and Weber http://pages.uoregon.edu/mbownik/papers/16.pdf, where specific examples of $\psi$ of this type are given for which they indicate they don't know how to prove whether it is a frame or not. In the 2004 Proceedings of the AMS paper of Dai, Diao, Gu and Han, they explicitly mention that the characterization of sets $E$ so that $\hat \psi = I_E$ and $\psi$ is a frame wavelet (for dilations by powers of 2 and integer translations) is open. There are currently not sufficient techniques available for dealing with the case that the canonical dual frame is not affine.
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https://puzzling.stackexchange.com/questions/55885/what-english-words-contain-the-vowel-letters-a-e-i-o-and-u-with-fewest-con/55891 | What English words contain the vowel letters, a, e, i, o, and u, with fewest consonant letters?
What English words contain the five vowel letters, a, e, i, o, and u, with fewest consonant letters?
Facetious and abstemious contain the five in alphabetical order, and each contains four consonant letters: fcts in facetious, and bstm in abstemious. There are two instances of s in the case of abstemious, but we are counting each letter once, so both words achieve a consonant score of four.
We are looking for the word or words that contain all five of these vowel letters, not necessarily in alphabetical order, and perhaps repeated, and that have the lowest consonant score.
(Note: please can nobody edit to change "vowel letter" and "consonant letter" to "vowel" and "consonant". "Vowels" and "consonants" are sounds - they are classes of phonemes, not classes of written letters. Often a vowel letter does not represent a vowel. I am also aware that y often does represent a vowel and that w sometimes does.)
• One day I was playing Scrabble with a friend, and she said How interesting, I have all five vowels, and I said jokingly well then if you also have an S and a Q then you can play SEQUOIA, and then she did. I was vexed. – Eric Lippert Oct 13 '17 at 14:11
• We also have "giouae", which is the sound I make when I wake up in the morning. – MackTuesday Oct 13 '17 at 16:04
• Caesious has all five vowel letters in order and only three consonant letters. – Peter Taylor Oct 13 '17 at 17:40
• en.wikipedia.org/wiki/Words_without_consonants – SeanC Oct 13 '17 at 20:47
• It's not an answer, but I like facetious because it's a (fairly) common word with the five vowels in order. If you like y, then go with facetiously. – Engineer Toast Oct 13 '17 at 21:14
Iouea (noun)
1. A taxonomic genus within the phylum Porifera — Cretaceous fossil sponges.
contains all five vowels, although it is a scientific word. As an alternative,
Eunoia (noun)
1. (rhetoric) Goodwill towards an audience, either perceived or real; the perception that the speaker has the audience's interest at heart.
contains all vowels and one consonant. This is also the shortest word to contain all vowels.
As a bit of trivia, Christopher Bök's Eunoia is an anthology of poems, where each chapter is written using words limited to a single vowel.
• Wow, that was fast! I will accept, because nobody will beat this, but are there any other words that score one? – user36946 Oct 13 '17 at 9:56
• I can't seem to find eunoia in any well-known dictionary, apart from Wikitionary. Could you provide a link to something like the Oxford English Dictionary? – boboquack Oct 13 '17 at 10:01
• Eunoia is not in the OED. – user36946 Oct 13 '17 at 10:06
• @boboquack You might be interested to know that the Guinness World Records lists eunoia as the smallest word containing all five vowels. Definitions can be found here, here and here, although the word is not an accepted scrabble one. – user40086 Oct 13 '17 at 10:07
• you specifically ask for english, but as a gift, i will give you the french version: oiseau(bird). – dna Oct 13 '17 at 14:40
Here's a word I have just found in the Oxford English Dictionary that achieves a score of one:
mieaou
It's a variant spelling of
miaow.
This problem seems familiar (not from another PSE question) and I can remember two answers that came up with a score of:
2 consonants
which were:
Sequoia and miaoued
Note: the second was contentious to whether it was in fact a valid word, but the first definitely is.
Maybe this takes the fun out of the question, but it is a computational problem. I obtained the list of words only containing alphabetic characters here (words_alpha.txt): https://github.com/dwyl/english-words. First, find all uncapitalized words (avoiding proper names) that contain all the vowels:
grep '^[a-z]' words_alpha.txt | grep a | grep e | grep i | grep o | grep u > tmp1
Then remove vowels and print the remaining length (number of consonants):
sed 's/[aeiou]//g' tmp1 | awk '{print length($0)}' > tmp2 Finally, paste the counts next to the corresponding word, sort and take those with less than four consonants: paste tmp2 tmp1 | sort -g | awk '$1 < 3'
2 aboideau
2 aboiteau
2 eucosia
2 eulogia
2 eulogiae
2 eunomia
2 eutocia
2 eutopia
2 miaoued
2 moineau
2 sequoia
So in this list, no word has less than two consonants, while twelve words have exactly two consonants.
• Welcome to Puzzling! Why don't you take the tour? – boboquack Oct 13 '17 at 22:06
• Duplicated consonant letters should be counted as one: cat words_alpha.txt | grep -i 'a' | grep -i 'e' | grep -i 'i' | grep -i 'o' | grep -i 'u' | ruby -e 'ARGF.each{|w| w=w.strip.downcase; s=w.split("").sort.join; s=s.gsub(/[aeiou]/,""); s2=s; s2=s2.gsub(/(.)\1+/,"\\1"); puts "#{s2.length} #{w.length} #{w} #{s} #{s2}"}' | sort -n -r. – psmith Oct 14 '17 at 9:49
I found two words with 2 points (apart from sequoia):
aurevoir attenuation
Though the first one is bending the rules a bit :)
I mentioned CAESIOUS in a comment as having three consonant letters, but I had missed that the score is based on distinct consonant letters, so it scores 2 and is worthy of elevation to an answer. It has the additional nice property of having each of the vowel letters exactly once and in order.
SOWPODS contains a further 12 words scoring two, of which 8 have been listed in previous answers, and one (SEQUOIAS) is a simple plural of one which has. The three additions are
• DOULEIA (not exactly a word of quotidian usage, at least in the circles I move in)
• OSSUARIES (probably the two-pointer I use second most after ATTENUATION)
• AUTOCUTIE (which I've never heard before, but apparently does see some use)
For completeness, the other two-pointers in SOWPODS are
• ABOIDEAU
• ABOITEAU
• ATTENUATION
• EULOGIA(E)
• MIAOUED
• MOINEAU
• SEQUOIA | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 0, "mathjax_asciimath": 1, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.24936464428901672, "perplexity": 3848.0806132039743}, "config": {"markdown_headings": false, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 5, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2020-24/segments/1590347387219.0/warc/CC-MAIN-20200525032636-20200525062636-00232.warc.gz"} |
https://math.stackexchange.com/questions/1949421/solve-exponential-equation-using-the-mean-value-theorem | # Solve exponential equation using the mean value theorem
Solve $3^x + 6^x = 5^x + 4^x$ using Lagrange's mean value theorem's.
I believe all I have to do is apply Lagrange's theorem on some function on a given interval, but I know neither the function to apply on nor the interval.
So, please, help me if you know how.
You are trying to solve: $6^x-5^x=4^x-3^x$. The mean value theorem says that $6^x-5^x=xa^{x-1}$ for some $a\in [5,6]$, and that $4^x-3^x=xb^{x-1}$ for some $b\in [3,4]$.
So, given that you known $a\in [5,6]$ and $b\in [3,4]$, when is it possible that:
$$xa^{x-1}=xb^{x-1}?$$ | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 1, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.9675589799880981, "perplexity": 168.81145575430338}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2019-35/segments/1566027317339.12/warc/CC-MAIN-20190822172901-20190822194901-00470.warc.gz"} |
https://ece4uplp.com/generation-of-pwm-and-ppm-using-wave-forms/ | # Generation of PWM and PPM using Wave forms
PWM Generator:-
The circuit that generates PWM wave is as follows, Here in this circuit Op-Amp works in comparator mode.It compares two voltages, modulating voltage with Saw-tooth Voltage. Saw-tooth voltage is taken as reference voltage.
condition Output voltage Vo(t) $m(t)>&space;V_{r}(t)$ Low $V_{r}(t)>m(t)$ High
from the graphs whenever modulating voltage dominates saw-tooth voltage corresponding output is low.
Similarly, when saw-tooth voltage dominates modulating voltage corresponding output is High.
Then the resultant output voltage is a PWM signal.
PPM Generator:-
Now, a PPM signal has been generated by passing the PWM signal through a Mono-stable Multi vibrator . Here the resultant signal is a PPM signal with the pulse starting with respect to trailing edge of PWM signal.
The width and Amplitude of Pulse remains constant only the position of the pulse changes with respect to m(t) .
(No Ratings Yet) | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 2, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.8016115427017212, "perplexity": 7562.075907945661}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 20, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2019-43/segments/1570986718918.77/warc/CC-MAIN-20191020183709-20191020211209-00189.warc.gz"} |
https://codeforces.com/blog/entry/64067 | ### Vovuh's blog
By Vovuh, history, 6 months ago, translation, ,
My session is almost done and holidays are just around the corner. It means that it's time for another one contest! Happy New Year to all of you!
<copy-pasted-part>
Hello!
Codeforces Round #529 (Div. 3) will start at Dec/27/2018 17:35 (Moscow time). You will be offered 6 or 7 problems with expected difficulties to compose an interesting competition for participants with ratings up to 1600. Probably, participants from the first division will not be at all interested by this problems. And for 1600-1899 the problems will be too easy. However, all of you who wish to take part and have rating 1600 or higher, can register for the round unofficially.
The round will be hosted by rules of educational rounds (extended ACM-ICPC). Thus, during the round, solutions will be judged on preliminary tests, and after the round it will be a 12-hour phase of open hacks. I tried to make strong tests — just like you will be upset if many solutions fail after the contest is over.
You will be given 6 or 7 problems and 2 hours to solve them.
Note that the penalty for the wrong submission in this round (and the following Div. 3 rounds) is 10 minutes.
Remember that only the trusted participants of the third division will be included in the official standings table. As it is written by link, this is a compulsory measure for combating unsporting behavior. To qualify as a trusted participants of the third division, you must:
• take part in at least two rated rounds (and solve at least one problem in each of them),
• do not have a point of 1900 or higher in the rating.
Regardless of whether you are a trusted participant of the third division or not, if your rating is less than 1600, then the round will be rated for you.
Thanks to MikeMirzayanov for the platform, help with ideas for problems and for coordination of my work. Thanks to my good friends Mikhail PikMike Piklyaev, Maksim Ne0n25 Mescheryakov and Ivan BledDest Androsov for help in round preparation and testing the round.
Good luck!
I also would like to say that participants who will submit wrong solutions on purpose and hack them afterwards (example) will not be shown in the hacking leaders table.
</copy-pasted-part>
UPD: After the contest, you can discuss the problems in the community Discord server. Maybe I will take part in the discussion.
UPD2: Editorial is published!
UPD3: I forgot to thank my friend Roman Ajosteen Glazov for helping me with testing the round!
UPD4:
Congratulations to the winners:
Rank Competitor Problems Solved Penalty
1 sai_150050066 6 114
2 Skeercg 6 167
3 golubtsowroman 6 167
4 phungtienminh 6 170
5 forloop 6 183
Congratulations to the best hackers:
Rank Competitor Hack Count
1 MZuenni 219:-8
2 ______-__________-______ 105:-39
3 bacali 81:-66
4 Random456 15:-2
549 successful hacks and 540 unsuccessful hacks were made in total!
And finally people who were the first to solve each problem:
Problem Competitor Penalty
A ChiIIi 0:01
B GreacaEgalLuluOri2 0:02
C ChiIIi 0:05
D ChiIIi 0:12
E hahahahaha111 0:13
F kuchnaahopaayega 0:16
• +141
» 6 months ago, # | +9 Didn't we just have a div 3 this week? Instead, why not have an educational? Since the difficulty of these contests is comparable to that of div 3 contests and it would be rated for a larger audience.
• » » 6 months ago, # ^ | +8 We have an educational round on 28th already :)
• » » » 6 months ago, # ^ | +10 Yeah, so the questions could have been used for an educational contest someday after good bye-2018.
» 6 months ago, # | +1 Awesome Anyway I love Live Contests so much Great Job for your efforts on Writing and testing the problems Happy New Year for all
» 6 months ago, # | ← Rev. 3 → -19 Just first div 3 contest was the real div 3. (in problem difficulty)
» 6 months ago, # | +11 If the difficulty trend in Div3 rounds keeps going, we might have to expect IOI level problems.
• » » 6 months ago, # ^ | +57 Hey, it's IOI jury's problem that their task was easy enough to fit into div3 contest!
» 6 months ago, # | ← Rev. 2 → -33 Eden Hazard the best player in the world right now
» 6 months ago, # | 0 Div 3 is easy for me, give me div 4
• » » 6 months ago, # ^ | 0 But div 1 > div 2 > div 3
» 6 months ago, # | ← Rev. 2 → -21 is it contributed?
» 6 months ago, # | -6 Good luck!
» 6 months ago, # | -29 is A FFT?
» 6 months ago, # | -17 hope this round results in a higher rating to all my friends ... Good luck to all
» 6 months ago, # | ← Rev. 2 → -19 Why I see the "" again...Could you pay more attention when writing an announcement?
• » » 6 months ago, # ^ | 0 At least he is spending time for making the contest. Announcement is not important more important is how he settled all the div3 contests so beautifully.
• » » » 6 months ago, # ^ | -7 I agree with you,but I think a good announcement is also important.
• » » 6 months ago, # ^ | +6 Meh, why would you need a different announcement every time? Announcement notifies you of contest (in case you only look at main page and not the schedule) and reminds you a bit of the rules. This one makes its job pretty fine, I guess. It feels like a waste of time to write it from scratch every time.
» 6 months ago, # | ← Rev. 3 → -30 ****_ahaahaahaahha bad contest you have brain or no? wtf?_**** ****_Div1+Div2=Div3_**** ****_Eden Hazard the best player in the world right now_**** ****_is it contributed?_**** ****_hello i live in a very rural part of czechoslovakia and i am wondering if the contest is contributed and or rated for me thank you_**** ****_are you ssure? i cant find it x(_**** ****_ahahahahaha one two three 123_****
» 6 months ago, # | ← Rev. 2 → 0 Just first div 3 contest was the real div 3. (in problem difficulty)
» 6 months ago, # | 0 I hope it is not like the previous contest
• » » 6 months ago, # ^ | ← Rev. 2 → -11 I hope it is not like you
» 6 months ago, # | 0 I will do my best and I want to get gray
• » » 6 months ago, # ^ | 0 I think so
» 6 months ago, # | ← Rev. 2 → +10 Good luck folks! Image
» 6 months ago, # | ← Rev. 3 → +18 Good luck to the server
» 6 months ago, # | +18 Thanks vovuh for div 3 again. I like the higher frequency for div 3 these days.Hope it's a great contest.
• » » 6 months ago, # ^ | +21 I hope so :) Good luck!
» 6 months ago, # | 0 How to hack a solution.
• » » 6 months ago, # ^ | 0 Go to standings then click on any + sign
» 6 months ago, # | 0 Got 2 WA using pow() in C++ :( in problem C.
• » » 6 months ago, # ^ | +5 Try to use byte shifts. For example (1 << 5) is equal to pow(2, 5). This is only for powers of number 2.
• » » » 6 months ago, # ^ | 0 Yes, I had corrected it in the last 2 minutes :)
• » » » » 6 months ago, # ^ | 0 you can use int(pow(2,i)), but bit shift works fine too
» 6 months ago, # | 0 How is there 100% systests already? O_o
• » » 6 months ago, # ^ | 0 Maybe because it has already the pretests passed, I guess the test should happen after the hack phase is over, otherwise, maybe the machines were ultra fast today
• » » 6 months ago, # ^ | -8 Yeah you can use a segment tree for it. The leafs should store the count to open and closed brackets.
• » » » 6 months ago, # ^ | +1 Thank you :)
• » » 6 months ago, # ^ | ← Rev. 2 → +9 If a '(' represents 1 and a ')' represents -1 then the bracket sequence is valid if and only if every prefix sum is non-negative and the total sum is 0. When you change a '(' into a ')' it subtracts 2 from every prefix sum starting from that point. The opposite change has the opposite effect. Now just figure out which of these changes make the prefix sums non-negative and the total sum equal to zero.
• » » » 6 months ago, # ^ | 0 Thank you!
• » » » 6 months ago, # ^ | ← Rev. 2 → 0 what about this "))((" it will be equal to zero however it is not valid??
» 6 months ago, # | +20 thanks for an actual Div 3 round!!! on a side note, does anyhow know how to D? I struggled at it quite a bit.
• » » 6 months ago, # ^ | +1 If two integers are in the same line, this means they're adjacent in the graph. The input gives you all n edges in the graph (though maybe not oriented correctly).Arrange the edges to form a cycle. You may need to reverse your output if the edges are facing the wrong direction.
• » » » 6 months ago, # ^ | +10 that's the problem I'm facing — how do you know if the edges are in the wrong direction?
• » » » » 6 months ago, # ^ | 0 Look at the first 3 values. If they match what's given in the input, then the solution is facing the correct direction. Otherwise, reverse the output.
• » » » » » 6 months ago, # ^ | 0 I checked that reversing conditions for all n, if it's true i incremented the counter variable.At last if that counter having value equal to n i reverse the output else not.I got AC.But don't understand the reversing condition.Can any one can help?
• » » » 6 months ago, # ^ | -9 i tried topological sort but it gave me WA on test 3
• » » » » 6 months ago, # ^ | 0 Topological sort doesn't guarantee a unique tree, which is what you want (as you'd be breaking the cycle otherwise). The generated trees depend on the order in which you visit the neighbors, which explains why you got WA on the third test.
• » » 6 months ago, # ^ | -7 The approach I used is slightly different: if a and b are on the same line, then either b occurs on the line of a or a occurs on the line of b. We check which of these two is the case, and immediately know whether there is an edge from a to b, or from b to a. By doing this operation for every line, we calculate all the edges with the correct direction. The only problem with this approach is that it may give incorrect answer for n = 3; but outputting 1 2 3 always works if n = 3, since the all the inputs for 1 3 2 would be correct for 1 2 3, as well.
• » » » 6 months ago, # ^ | 0 Damn, used the very same approach. Didn't handle the case of 3 properly. https://codeforces.com/contest/1095/submission/47583430
• » » 6 months ago, # ^ | -13 ezaf dude, if a[a[i]] == b[i] or b[a[i]] == b[i] then next_to[i] = a[i], else next_to[i] = b[i]. then print 1, next_to[1], next_to[next_to[1]], ...
• » » 6 months ago, # ^ | 0 Since n>=3 Consider if we are at node "a" and we know by input that node "b" and node "c" are its next nodes So, case would be likeCase-1 : a->b->c Case-2 : a->c->bTo verify which is the case , simple check that if "c" comes in the next_nodes_list of "b". Then it will be Case-1. If "b" comes in the next_nodes_list of "c", then it will be Case-2 If it is case-1 , then it is sure "c" does not contain "b" in its next_nodes. If it is case-2 , then it is sure "b" does not contain "c" in its next_nodes.Use this above condition and put nodes in order.
• » » 6 months ago, # ^ | ← Rev. 2 → 0 I solved it in the following way — 1) every number will appear exactly 2 times, one in the vertex to which it is next and and secondly in the vertex where it is next to next. 2) lets look for the vertices for which we get 1, and let then be called vertex a and b. so the order is either a b 1 or b a 1. 3) we go to vertex a and look for b , if b is there it means b comes after a so the order is a b 1, or if not present the order is b a 1. 3) After getting the order of first 3 element we will look for the adjacent vertices of vertex at index 1 [ 'b' in case of a b 1, and 'a' in case of b a 1], the vertex other than 1 will be the vertex at index 3, after we will repeat this process for all the vertices up to index n-3. my submission, time complexity O(n)
» 6 months ago, # | 0 Problem E was almost the same as BRCKTS problem from SPOJ.
• » » 6 months ago, # ^ | ← Rev. 2 → 0 jg
» 6 months ago, # | -47 Easy round, I solved all problems
• » » 6 months ago, # ^ | +8 You mean you consistently got WA on testcase 2 on all problems?
» 6 months ago, # | -8 Does hacking help my rating?
• » » 6 months ago, # ^ | -23 Yes, it helps your rating
• » » 6 months ago, # ^ | +2 You don't get points for hacking in Div. 3. It helps you indirectly by making you place higher in the standings.
» 6 months ago, # | 0 !(my last comment) = I love div3 rounds :Panyway how to solve D it looked like a graph problem to me
• » » 6 months ago, # ^ | 0 There is no need for graph. Using 1 as the first number, find the first 3 numbers with brute force. Then its easy implementation.
• » » 6 months ago, # ^ | ← Rev. 2 → 0 It was a simple implementation problem. You just need to find a possible permutation of first 3 elements. lets say, p1, p2 and p3. Then you can easily find the rest elements. How?Finding part 2 is easy,As you know p2 and p3, you can easily find p4 because, only number after p2 other than p3 is p4.In other words, a21 = p3 => p4 = a22; And so on, we can find p5, p6....pnFor part 1,Fix p1 lets say '1'; now p2 and p3 can be either a11 or a12. How to fix them?If a21 = p3 or a22 = p3 then p1, p2, p3 is correct; else p1, p3, p2 is correct;Check my submission: https://codeforces.com/contest/1095/submission/47575058
• » » » 6 months ago, # ^ | 0 damn they scared me with that circle
• » » » 6 months ago, # ^ | 0 Hi Can you please point out why my solution got WA on 285th Kid https://codeforces.com/contest/1095/submission/47585800.
• » » » » 6 months ago, # ^ | 0 Your code's logic seems incorrect. Please try this simple input: 5 5 4 1 5 2 1 3 2 4 3 Output should be (a cyclic shift of): 1 5 4 3 2But your code is printing: 1 5 4 2 3
» 6 months ago, # | 0 Can I get a hint for problem C:Powers of 2
• » » 6 months ago, # ^ | 0 Check the binary representation of the input
• » » 6 months ago, # ^ | 0 First find the binary representation to know the minimum powers necessary. Now, if we can represent n using x powers of 2, then we can also do it using x+1 powers of 2, provided x < log2(n). Think about how to get x+1 powers from x powers.
• » » » 6 months ago, # ^ | 0 Can you elaborate further by taking an example?
• » » » » 6 months ago, # ^ | ← Rev. 3 → +1 Suppose you have x slices of pizza, but you want to have x+1 slices what do you do, divide one of the slices into 2, now you have x+1 pizza slices.Similarly, if you have minimum powers of 2 necessary to make a number. you can keep on dividing the numbers till you get k numbers.you can also do it recursively. See my codes: 1) Recursive 2) Iterative (Using a queue)
• » » » » » 6 months ago, # ^ | 0 i cannot understand why u use k-=mn; then func( x, min(k+1,x) ) in your code can you eloborate please
• » » » » » » 6 months ago, # ^ | ← Rev. 2 → 0 Well, it's hard to explain because I have done it in a messy way, What I am just doing is that for each number in binary representation of n, I keep on dividing it till I have k numbers. For example: Take n=10 it can be represented in minimum powers as: 8+2 I keep on dividing 8, then I go to 2 then I keep on dividing it. When I have k numbers I stop dividing.You can build your own logic for this.
» 6 months ago, # | ← Rev. 3 → 0 Wonder why Problem F if there are Multiple index have smallest cost pick any of them to build edge to is ok
• » » 6 months ago, # ^ | 0 you can refer to MST Algorithm like Prim and Kruskal
• » » » 6 months ago, # ^ | 0 i means the given a1~an may have multiple of them have same smallest value and why i pick any of them build edge connect to others the answer will be same
• » » » » 6 months ago, # ^ | 0 you can consider why MST Algorithms like Prim and Kruskal do not care about that
• » » 6 months ago, # ^ | +3 Assume we've already chosen which special edges will be present in our tree. We need to figure out the cheapest way to join the connected components that they induce.The total weight for the other edges is some expression of the form ai1 + ai2 + ... + aik. We have to choose at least one vertex from each connected component induced by the special edges, so the minimal possible value of the expression for fixed k (ignoring any other restriction) is obtained by first adding the smallest ai from each component, and then adding the smallest ai of them all however many times. By choosing any vertex with minimum cost we will get exactly this value for the expression, so it doesn't matter which one we choose.
• » » » 6 months ago, # ^ | 0 Thanks. I think i got it.
» 6 months ago, # | 0 Can F be solved by Prim's Algorithm? I thought this is MST problem, but how can we find MST when we have so many edges? I know we can use binary heap, priority queue and some data structures on Prim's algorithm, but I don't get how to fit in time and memory. Plz let me know if I'm missing something.. (I'm not even sure if this is a MST problem or not)
• » » 6 months ago, # ^ | 0 It is MST, with an extra idea. It turns out the only edges with costs ax + ay that we need to consider are the ones that involve the vertex with minimum cost.
• » » » 6 months ago, # ^ | 0 Thanks! I'll go study more through it :)
• » » 6 months ago, # ^ | 0 It is a MST problem. Use the set 1 as the given edges. find the smallest ai and make n-1 edges this vertex to other vertices. Call this set 2 of edges. combine both sets and apply prim's algo.
» 6 months ago, # | 0 Any one can help me with problem E! I have no idea how can i solve the problem!
» 6 months ago, # | 0 I'm getting a wrong answer by the checker but if I compile it elsewhere I get the right solution.The checker's log read: wrong output format Unexpected end of file — int32 expectedCan someone explain what is happening Submission
• » » 6 months ago, # ^ | 0 It means that your solution just terminated when jury has some output left to check. In your submission, jury had one more integer number to check, but your execution ended without giving an integer.
• » » » 6 months ago, # ^ | 0 But if I compile the same code elsewhere I'm getting a correct answer as per the jury.
• » » » » 6 months ago, # ^ | 0 Can you specify about your machine or where you compiled?I mean, some links to online compiler or you machine's OS, editor, complier
• » » » » » 6 months ago, # ^ | 0 Online compiler Jdoodle
• » » 6 months ago, # ^ | 0 Should I report it to someone?
• » » » 6 months ago, # ^ | 0 vovuh Please look into this.
• » » » » 6 months ago, # ^ | 0 Lol. I looked into this and I can say you should remove your 'very useful' optimization pragmas because your solution works fine without them. But I don't know what is the real problem because I don't know anything about such 'optimizations'. Maybe MrDindows can help you?
• » » » » » 6 months ago, # ^ | 0 I can, that's because of abm in target. https://codeforces.com/blog/entry/59457?#comment-431178
• » » » » » » 6 months ago, # ^ | 0 Thanks, that's quite interesting!
» 6 months ago, # | 0 In Problem D, can the permutation be in any cyclic order (clockwise or anti-clockwise)? Like for this test case 5 3 5 1 4 2 4 1 5 2 3is this 1 4 2 3 5 also a valid answer?
• » » 6 months ago, # ^ | ← Rev. 2 → 0 No. 1 4 2 3 5 is invalid. You must consider the order. (i.e standing in front or back matters)You should check clockwise or counterclockwise. After that, starting point doesn't matter.1 5 3 2 45 3 2 4 13 2 4 1 52 4 1 5 34 1 5 3 2These are the only valid answers for first example.
• » » » 6 months ago, # ^ | 0 I tried to think of making a bi-directional graph and then apply a DFS. But it didn't seem to work out. Not able to figure out how to determine the order?
» 6 months ago, # | ← Rev. 2 → 0 Problem D is ambiguous, I cannot understand what he want. can anyone help me please. thanks in advance.
• » » 6 months ago, # ^ | 0 There's a directed circle(a premutation p), giving the two vertexes behind every vertex, you should print a valid order.
• » » » 6 months ago, # ^ | 0 Ycrpro1 thanks bro, i got Acc
» 6 months ago, # | +1 Why all Java solutions on B are getting hacked? Although they all seem correct.
• » » 6 months ago, # ^ | 0 MZuenni on fire!
• » » » 6 months ago, # ^ | +8 Java's DualPivotQuicksort used in Arrays.sort is deterministic and therefore in O(n^2) they all get timelimit by that...
• » » » » 6 months ago, # ^ | 0 Good Job! Even though I was one of the victim, felt good to learn these intricate things.Cheers!
• » » » » 4 months ago, # ^ | 0 But isn't time complexity of Arrays.sort() changed to O(nlogn) for worst case too in Java 8?
• » » » » » 4 months ago, # ^ | 0 no.https://docs.oracle.com/javase/8/docs/api/ Implementation note: The sorting algorithm is a Dual-Pivot Quicksort[...]
• » » 6 months ago, # ^ | 0 May be for this reason : Link
• » » » 6 months ago, # ^ | 0 yes thats correct. p.s. for all people writing me direct: i have reached my codeforces message limit and therefore cant respond for the next hour...
» 6 months ago, # | ← Rev. 2 → 0 Why did my solution for F Link failed?? Update:Solved
• » » 6 months ago, # ^ | +3 your variable mst_cost is int.... it should be long long
• » » » 6 months ago, # ^ | 0 Yup,that was the problem, just got an AC, Thanks acIN1go
» 6 months ago, # | ← Rev. 2 → 0 for problem D, why WA??? Judge says wrong output format Unexpected end of file — int32 expectedlink to my code is Your text to link here... please someone check it...
• » » 6 months ago, # ^ | 0 You should be printing 5 numbers and you only printed 2
• » » » 6 months ago, # ^ | 0 yes, that's the problem. IDE prints all the five values but, judge shows only two. I'm not getting the reason.
• » » » » 6 months ago, # ^ | ← Rev. 2 → 0 1) I had the same issue before, that happens because the current compiler makes some "corrections" to the code at runtime, to see the exact result on your ide (in this case Codeblocks) you should make it follow the C++11 standard as seems in this link2) About your code, I got it working removing adj = new list[n + 2]; and vis = new int[n + 2]; but instead delcaring adj and vis like this list adj[200001]; int vis[200001];It's a good practice to declare your variables as globals and at the same time with the max length posible since that way only you can be sure they are fully initialized (the default compiler in our machines does some tricky stuff when a variable is not propelly initialized and instead of giving an error it tries to make it work which makes us think it works propelly meanwhile codeforces and other evalutaros don't do that)
» 6 months ago, # | 0 A lot of people got hacked on Problem B, including myself. Does anybody know what the issue could have been?
• » » 6 months ago, # ^ | 0 Hey:)So Java's Arrays.sort() uses quicksort, and the average runtime is nlogn but worst case runtime is n^2. The hack is an anti-quicksort hack. To fix this, you should declare the array as Integer[] rather than int[], since merge sort is used to sort objects, which runs in time.
• » » » 6 months ago, # ^ | 0 Thanks! I'll remember that for future reference.
» 6 months ago, # | 0 What does this statement mean in problem "F. Make It Connected"?You don't have to use special offers: if there is a pair of vertices x and y that has a special offer associated with it, you still may connect these two vertices paying ax+ay coins for it.
• » » 6 months ago, # ^ | ← Rev. 2 → 0 If an offer with cost w is included, the cost of building an edge connecting x and y can be either ax + ay or w, it's up to your choice (yet obviously if you're really going to build that edge you would want the minimum value between them).
• » » 6 months ago, # ^ | 0 For two vertices x and y, there may be some special offers. You may potentially use one of these offers during the construction if you want to connect x to y. However, you can connect x to y without using any of these offers, as well. In that case, the cost of connecting x and y is given by ax + ay.
» 6 months ago, # | ← Rev. 2 → 0 Today during contest I got WA on test 1, for problem D. While it ran well on my IDE with correct answer. My submission: https://codeforces.com/contest/1095/submission/47569625Later after 20 mins I realized, I had left a return false; statement inside the check() function. After adding the line it got accepted. (https://codeforces.com/contest/1095/submission/47575058). If it wouldn't have worked on my IDE I would have fixed it and submitted in matter of seconds, rather than 20 mins of trying to find some error which still works fine on my IDE. Any ideas why it worked fine for all sample cases plus my own custom cases, on my IDE but not on cf server?
• » » 6 months ago, # ^ | +1 It's called "undefined behaviors".Since the function return a non-void value and you left its ending ambiguous (not stating explicitly if it would return true or false), so depending on the compiler and environment of your PCs, IDEs or online judges, the returning value will fluctuate.
• » » » 6 months ago, # ^ | +8 Oh, now it makes sense. Thanks for the clarification :)
• » » » 6 months ago, # ^ | 0 (https://codeforces.com/contest/1095/submission/47597346) Dude, can you please check my code once. it prints all 5 numbers on the IDE, but here it prints only two digits and says wrong output format Unexpected end of file — int32 expected.
» 6 months ago, # | -30 declare the round unrated for java users whose B was hacked!
• » » 6 months ago, # ^ | -6
• » » » 6 months ago, # ^ | +3 why should that happen?there is no difference between getting hacked or failing the system tests (there are also enough problem setters who directly include such testcases for systemtests so no hack is needed).And you will learn from this and will think about this the next time you use Arrays.sort...
• » » » » 6 months ago, # ^ | +1 but that works perfectly well with c++, as it is faster
• » » 6 months ago, # ^ | 0 they gave the java users only 1k ms they should have given 2k ms
» 6 months ago, # | -16 For java we are allowed 2000 ms for a problem in which the limit is 1000ms but here we got a tle at 1000mssubmission here: http://codeforces.com/contest/1095/submission/47602564please rectify this
• » » 6 months ago, # ^ | 0
• » » » 6 months ago, # ^ | +2 the problem is NOT that java is generally slower! the problem is that you used an algorithm which is in O(n^2) which is clearly to slow!
• » » » » 6 months ago, # ^ | 0 So according to you what could be an alternative to Arrays.sort() for getting O(nlogn)?
• » » » » 6 months ago, # ^ | 0 According to the documentation of Arrays.sort() Implementation note: The sorting algorithm is a Dual-Pivot Quicksort by Vladimir Yaroslavskiy, Jon Bentley, and Joshua Bloch. This algorithm offers O(n log(n)) performance on many data sets that cause other quicksorts to degrade to quadratic performance, and is typically faster than traditional (one-pivot) Quicksort implementations.
• » » » » 6 months ago, # ^ | +1 hey i read your blog. Thanks for the information, I got what you were trying to say.
» 6 months ago, # | 0 I Learn a very important thing in this contest. DO NOT FEAR to read hard problems. I am able to solve problem F easily with kruskal, but i didn't solve it during the contest because I always thought that if I can't solve easier problems (problem C and E), i can't solve the harder one.
• » » 6 months ago, # ^ | -7 chong
» 6 months ago, # | -11 Hi Everyone, I got a runtime error due to wrong evaluation of log(n)/log2 by the CF compiler, but it is being evaluated fine in my own ide, and a number of online compilers. Isnt it unfair for me. my submission,problem c. For input 8,1 CF compiler is evaluating it as 2, where as it should be evaluated as 3
• » » 6 months ago, # ^ | +3 Nope, it crashes in your while while((k-cnt) != 0){ ...
• » » » 6 months ago, # ^ | 0 yes, but thats because 'sz' was evaluated as 2, if it would have been evaluated as 3, I would have got "YES 8"
• » » » » 6 months ago, # ^ | ← Rev. 3 → +3 Gotcha, it's weird behavior. As to why, i guess you should consider that doubles aren't exact just as the result of log() isn't, so the division isn't exactly 3. You should avoid doubles whenever possible, in this case when you want to check over log in base 2 you should use bit operations.
• » » » » » 6 months ago, # ^ | 0 yep, ceil would have done it.
• » » 6 months ago, # ^ | +3 Try using log2(n) instead of log(n)/log(2). Idk, it may work or not, but you should have gone for ceil value anyway.
» 6 months ago, # | 0 When will the ratings change?
» 6 months ago, # | +3 I love Vovuh's Problem set...He is making Div3 great
» 6 months ago, # | 0 My Submission 47584196 was rejected by Codeforces compiler because the values of INT_MAX and LONG_MAX are apparently same on codeforces it works perfectly on my laptop! Isn't this unfair to me? What can i do about this now?
• » » 6 months ago, # ^ | -6 They are same on codeforces, because they are same in C++. (long and long long are different).See here.
• » » » 6 months ago, # ^ | 0 On my machine they are different! :(This is so unfair :|
• » » » 6 months ago, # ^ | 0 Even on GeeksforGeeks they are different!https://ide.geeksforgeeks.org/gL0gqCYQVs
» 6 months ago, # | ← Rev. 2 → 0 Could someone help me with problem E? I think I have not understood what is a regular sequence. In the first example — (((()) , can I change the second bracket to get ()(()) or change the 4th to get ((())) ? I can insert 1 and + into them such as (1)+(1+(1+1)+1) and (1+(1+(1)+1)+1) but why are they not regular ones?
• » » 6 months ago, # ^ | 0 Please read the description carefully!
» 6 months ago, # | 0 What is the solution to Problem B? I am getting WA on test case 6.
• » » 6 months ago, # ^ | 0 There is 3 cases. The first one is to take one element that is not minimum nor maximum: The instability doesn't change. The second case is to take one element that is maximum: The instability will be the maximum of the new array minus the minimum of the array. The third one is to take one element that is minimum: The instability will be the maximum of the array minus the minimum of the new array. So the answer is min(second case,third case).
» 6 months ago, # | 0
» 6 months ago, # | 0 In problem C, Many solutions are getting runtime error on test case 10 that is 1 1 But it is showing right output in almost every other compiler/IDEHere's my code. https://ideone.com/qVAsiL
• » » 6 months ago, # ^ | ← Rev. 2 → 0 I suspect that it is Undefined Behaviour. For test case 1 1, you pass 0, 0 as your arguments to the function rec(). It will return when y == 0 part without actually initialising vector V. So when you are executing this line fn(i,V.size()-1,0), V.size()-1 gives random big values and can be machine dependent. EDIT: I was right. Solution. It passes after removing ambiguity I mentioned.
» 6 months ago, # | 0 Is there any editorial posted for this Div3 Round?
» 6 months ago, # | 0 Can we have the editorials?
» 6 months ago, # | 0 How to approach problem E?
• » » 6 months ago, # ^ | +1 try to think when flipping a single character will make the whole sequence good , character can be "(" or ")" at each position so just two case, see what should be the number of EFFECTIVE "(" and ")" on both sides of concerned index. there difference must be one(you can verify). but we must be careful that either left or right side should not have parts which cannot be balanced either. while going left to right(maintain array A) try to maintain the net effective number of "(" at each index, means for all 0<=i<=n-1 store number of free "(" from [0->i] , and do same for ")" while going from right to left(maintain array B) maintain num of free")" for each i . on which indices we should perform the tests because other indices may give positive test instead of them they are wrong->if for any l>=0 A[l]=-1 then we should not check for indices greater than l (convince yourself by examples) because they will never effect left part in any better way so range to check will be [0,l] l can be at max n-1 ,similarly in array B for index i<=n-1 check till you approch 0 or where it is negative first time.check should be made finally on intersection of [0,l] and [m,n-1] :)
• » » 6 months ago, # ^ | ← Rev. 3 → +5 Calculate balance of given string. Let bal[i]=balance of substring [0;i]. (Balance is a sum of opening and closing brackets). Now go through this array and check:1) if bal[i-1]<0 at any moment, then you can stop and print answer, because you won't be able to make correct bracket sequence later anyway.2) if s[i]=='(' then by changing it to ')' balance will decrease by 2 from [i;n-1] in bal[]. So you need to check that minimum in bal[] from i to n-1 is >=2 and bal[n-1]==2. If it is true then increment answer variable.3) if s[i]==')' then same logic. Just check if min>=-2 and bal[n-1]==-2.To find minimum on interval you can just use multiset. See my solution
• » » » 6 months ago, # ^ | 0 Your solution is pretty clear and easy to understand..Thank you. I understood the logic behind the problem.
• » » » 6 months ago, # ^ | 0 why we have to check min??? | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 1, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.32781967520713806, "perplexity": 1862.7340086200209}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2019-26/segments/1560627998605.33/warc/CC-MAIN-20190618023245-20190618045245-00320.warc.gz"} |
https://www.dickimaw-books.com/bugtracker.php?action=view&key=51&page=2&search_category=All | Latest news 2020-07-03: SmashWords sale (ends 31st July 2020): 50% off crime/SF novel The Private Enemy and 100% off (free!) I’ve Heard the Mermaid Sing.
# Bug Tracker
ID: 51 🔗 Closed (Not a Bug) glossaries 4.01 Ola Olsson 2013-12-28 07:40:19 Acronym disables glsentryfmt...
## Report
Adding the line makes the custom formatting go away...
\newacronym{apa}{apa}{Apa per Apa}
see the repro code.
### MWE
\documentclass{article}
\usepackage{glossaries}
\makeglossaries
\renewcommand*{\glsentryfmt}{%
\glsgenentryfmt
\ifglsused{\glslabel}{}{\space (\glsentrysymbol{\glslabel})}%
}
\newglossaryentry{distance}{name=distance,
description={The length between two points},
symbol={km}}
\newacronym{apa}{apa}{Apa per Apa}
\begin{document}
First use: \gls{distance}. Next use: \gls{distance}.
\end{document}
## Evaluation
This isn't a bug but is a feature of having a mixture of acronyms and regular entries in the same glossary. There are two issues:
1. As per section Acronym Options in the user manual, you can use the package option acronymlists to identify a glossary that contains acronyms. This sets up the display format for the given glossaries via \defglsentryfmt.
If \newacronym is used in a glossary that hasn't been identified in this way, then \newacronym will automatically add that glossary to the list of acronyms and will use \defglsentryfmt to setup the display style for that glossary. So to prevent \newacronym from overriding the display style for a particular glossary you need to have already identified that glossary as a list of acronyms using the acronymlists package option (or the equivalent \DeclareAcronymList command).
\usepackage[acronymlists=main]{glossaries}
or
\DeclareAcronymList{main}
2. Redefining \glsentryfmt only has an effect on glossaries that haven't had their display style changed via \defglsentryfmt. Since using all acronyms set their display style using \defglsentryfmt, the only way to change their style is to use \defglsentryfmt rather than redefining \glsentryfmt. So you would need to do:
\defglsentryfmt{%
\glsgenentryfmt
\ifglsused{\glslabel}{}{\space (\glsentrysymbol{\glslabel})}%
}
However, this will interfere with the way the acronyms are displayed so \gls{apa} will produce "Apa per Apa (apa) ()" which has an unwanted set of parentheses. Instead you need to modify the argument of \defglsentryfmt so that it checks if the entry is an acronym:
\defglsentryfmt{%
\glsgenentryfmt
\ifglshaslong{\glslabel}%
{}% this entry is an acronym so do nothing
{\ifglsused{\glslabel}{}{\space (\glsentrysymbol{\glslabel})}}%
}
The complete document is now:
\documentclass{article}
\usepackage[acronymlists=main]{glossaries}
\makeglossaries
\defglsentryfmt{%
\glsgenentryfmt
\ifglshaslong{\glslabel}%
{}% this entry is an acronym so do nothing
{\ifglsused{\glslabel}{}{\space (\glsentrysymbol{\glslabel})}}%
}
\newglossaryentry{distance}{name=distance,
description={The length between two points},
symbol={km}}
\newacronym{apa}{apa}{Apa per Apa}
\begin{document}
First use: \gls{distance}. Next use: \gls{distance}.
Acronym first use: \gls{apa}. Next use: \gls{apa}.
\end{document}
If you choose to upgrade to version 4.02, there's another approach:
\documentclass{article}
\usepackage[acronymlists=main]{glossaries}
\makeglossaries
\newacronymstyle
{my-custom-style}% style name
{% display
\ifglshaslong{\glslabel}%
{\glsgenacfmt}% acronym
{% not an acronym
\glsgenentryfmt
\ifglsused{\glslabel}{}{\space (\glsentrysymbol{\glslabel})}%
}%
}%
{% style definitions
\GlsUseAcrStyleDefs{long-short}% use the same style as 'long-short'
}
% switch to this new style:
\setacronymstyle{my-custom-style}
\newglossaryentry{distance}{name=distance,
description={The length between two points},
symbol={km}}
\newacronym{apa}{apa}{Apa per Apa}
\begin{document}
First use: \gls{distance}. Next use: \gls{distance}.
Acronym: \gls{apa}. \gls{apa}.
\end{document}
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Name: (Optional.) | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 1, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.33598166704177856, "perplexity": 8048.595219047653}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2020-29/segments/1593657163613.94/warc/CC-MAIN-20200715070409-20200715100409-00585.warc.gz"} |
http://mathoverflow.net/questions/34469/complete-problems-for-randomized-complexity-classes/120773 | # Complete problems for randomized complexity classes
It is believed that $BPP$ has no complete problems. Even for $BPP^O$ for a suitable oracle $O$ it is believed not to have complete problems, unless P=BPP. I wonder if the class MA (the randomized version of NP) has complete problems. For example, IP has complete problems (given that it is equal to PSPACE). There is a similar post asking about complexity classes with no complete problems. Here, I'm interested specifically on complete problems for MA. If the answer is positive, can you give some examples? I've tried google and the complexity zoo, but with no success.
-
Actually, it is not clear that BPP has no complete language. In fact, some (many?) complexity theorists believe BPP=P, in which case BPP has a complete language! – Tsuyoshi Ito Aug 4 '10 at 3:19
Yes, that's true. It is a very strong thig to say. I'll edit that part. Thanks – Marcos Villagra Aug 4 '10 at 3:35
As I wrote, I do not think that it is believed that BPP has no complete language. I am afraid that there is also something wrong with the second sentence because BPP^PSPACE=PSPACE has a complete language. I do not know the situation about MA, though. At least, I believe that no MA-complete language is known, because such a characterization of MA would be a huge discovery. – Tsuyoshi Ito Aug 4 '10 at 3:51
Yes, it actually should read "there exists" instead of "for any". – Marcos Villagra Aug 4 '10 at 4:14
## 3 Answers
In general, for randomized classes complete problems tend to be either promise problems or approximation problems (which means they don't technically satisfy the conditions for being complete problems).
If you allow approximation problems, you can get complete problems in BPP. For example, for BPP you can ask: given a Turing machine $M$, approximate the probability that it accepts within $t$ steps on input $x$, where $t$ is polynomial in the size of the input. It's clear that you can approximate this probability with a BPP machine (using simulation), and it's also obvious that any BPP language can be reduced to this problem. Technically, this problem isn't in BPP since it's not a language (i.e., its output is not $\{0,1\}$), so it's not BPP-complete.
You can turn this into a promise problem by imposing the "promise" that the acceptance probability either be greater than $\frac{2}{3}$ or less than $\frac{1}{3}$.
These complete promise problems or approximation problems play the same role that complete problems play for non-randomized languages, and they really deserve more respect from computer scientists. For quantum computing, the natural complete problems also tend to be approximation (or promise) problems, and they have been quite useful in the theory of quantum computing.
There is a natural promise problem from quantum computing (stoquastic Hamiltonian) which is MA-complete (and not trivially so). However, I don't believe there are any languages (non-promise problems with $\{0,1\}$ answers) known to be MA-complete.
-
Peter, thanks for the answer. But in general, can we ask something like: Let A and B be a complexity classes of promise problems such that $B\subseteq A$, but not known to be strictly included. If we assume $A\neq B$ then there exists a promise language $L$ which is intermediate for $A$? In other words, is there a theorem like Ladner's but for any complexity class (including randomized and quantum) considering promise languages? – Marcos Villagra Aug 4 '10 at 4:26
That's a really nice question. I don't know the answer. – Peter Shor Aug 4 '10 at 11:45
First, it isn't "clear" that $BPP$ has no complete problems: if $TIME[2^{O(n)}]$ requires circuits of size $2^{\delta n}$ for some $\delta > 0$ then $P = BPP$, in which case $BPP$ certainly does have complete problems! (This is a famous result of Impagliazzo and Wigderson from 1998.) Also, $MA$ is not known to have complete problems, but again, under plausible circuit complexity assumptions, $NP = MA$ in which case all $NP$-complete problems are $MA$-complete too. (This is due to Klivans and van Melkebeek, and others who have weakened/changed the assumptions under which $NP=MA$ holds.) But yes, complete problems for $BPP$ and $MA$ are not currently known.
Secondly, the "promise" versions of these classes have do natural complete promise problems. (A promise problem is a pair $(\Pi_{YES}, \Pi_{NO})$ where $\Pi_{YES}, \Pi_{NO} \subseteq$ {$0,1$}$^n$, and $\Pi_{YES} \cap \Pi_{NO} = \emptyset$. The crucial point is that we do not necessarily have $\Pi_{YES} \cup \Pi_{NO} =$ {$0,1$}$^n$, so some inputs may not be considered at all in a promise problem.) For example, the following promise problem is complete for $Promise-BPP$:
Given a Boolean circuit $C$ with AND/OR/NOT gates and $n$ inputs, where you are promised that either every input $x \in$ {$0,1$}$^n$ makes $C$ evaluate to $0$, or at least half the inputs $x \in \{0,1\}^n$ make $C$ evaluate to $1$, determine which of the two is the case.
Not sure who first proved that this problem is complete, though in the literature it is sometimes known as CAPP (for Circuit Approximation Probability Problem). One reference is Fortnow, "Comparing notions of full derandomization".
Similarly defined promise problems (with nondeterminism thrown in, naturally) are complete for $Promise-MA$.
-
Doh! Peter rang in a minute earlier! – Ryan Williams Aug 4 '10 at 3:52
Pretty much a tie, though. – Peter Shor Aug 4 '10 at 3:57
Ryan, yes your right, it's not clear. I've edited the post. Also, thanks for the nice example on CAPP. – Marcos Villagra Aug 4 '10 at 4:27
My own favorite complete problems are promise problems for the promise problem version of SZK (Statistical Zero-Knowledge). These complete problems have played a major role in the study of SZK, and the relations among them are fascinating per se. See "On the complexity of computational problems regarding distributions (a survey)" at http://eccc.hpi-web.de/report/2011/004.
Oded
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http://tex.stackexchange.com/questions/173194/passing-the-current-column-width-to-a-macro-for-table-headers | # Passing the current column width to a macro (for table headers)
In an attempt to separate the formatting of tables, and in particular their headers, from the content, I have produced the following code:
\documentclass{article}
\usepackage{array}
\usepackage{colortbl}
\usepackage{xcolor}
\newcolumntype{L}{>{\raggedright\let\newline\\\arraybackslash\hspace{0pt}}}
\newcolumntype{C}{>{\centering\let\newline\\\arraybackslash\hspace{0pt}}}
\begin{document}
\begin{tabular}{cLp{50mm}lr}
\rowcolor{black!20}
\fheader{50mm}{Venerable Institution of Higher Education} &
1 & California Institute of Technology (Caltech) & United States & 94.9 \\
\multicolumn{4}{c}{\ldots}\\
12 & University of California, Los Angeles (UCLA) & United States & 86.3 \\
13 & Columbia University & United States & 85.2 \\
14 & ETH Z\"urich -- Swiss Federal Institute of Technology Z\"urich & Switzerland & 84.5 \\
\end{tabular}
\end{document}
(data taken from Times Higher Education, universities chosen to have some with long names)
The idea is that table headers should be
• bold face
• centered
• bottom aligned
but that these choices should be easy to change globally. Therefore I have marked up the header cells using macros \vheader for variable-width columns, like c, l, r, and \fheader for fixed-width columns like p, m, b. It works:
But there are three things I don't like:
• The need to repeat the width of the column for fixed-width columns. I have found that \hsize will be set to the column width. But all my attempts to retrieve it and use it in the multicolumn preamble failed, nagging about misplaced \omit and the likes.
• The need to say explicitly whether this is a fixed or variable width column. Again, I tried code that checks whether \hsize was changed from its value outside the tabular, and uses different multicolumn preambles depending on that, but it disagreed with multicolumn processing.
• The need to say this for every cell, instead of once for the whole row. The tabu package has a \rowfont macro for instance, that can take care of the bold face and centering at least, though not the bottom alignment. But tabu is not maintained, and looking at the source code, this is a really brittle business that involves code in the preamble to remove the previous glue of columns, which is different depending on whether or not colortbl is used.
Suggestions for each and any of these would be welcome—sorry for asking three questions at once!
Edit: replaced booktabs by colortbl and a grey background for the header row. Coloured backgrounds are frequently asked for by designers, so it's important that this works. And colortbl can be difficult, with the background not filling the whole cell.
-
\newcommand\fheader[1]{\centering\arraybackslash\bfseries #1} ? Ah it doesn't work, sorry – yo' Apr 24 '14 at 9:22
\documentclass{article}
\usepackage{array}
\usepackage{colortbl}
\usepackage{xcolor}
\newcolumntype{L}{>{\raggedright\let\newline\\\arraybackslash\hspace{0pt}}}
\newcolumntype{C}{>{\centering\let\newline\\\arraybackslash\hspace{0pt}}}
\multicolumn{1}{c}{%
\cellcolor{black!20}\bfseries\begin{tabular}[b]{@{}c@{}}#1\end{tabular}}}
\begin{document}
\begin{tabular}{cLp{50mm}lr}
\header{Venerable Institution of\\ Higher Eductation} &
1 & California Institute of Technology (Caltech) & United States & 94.9 \\
\multicolumn{4}{c}{\ldots}\\
12 & University of California, Los Angeles (UCLA) & United States & 86.3 \\
13 & Columbia University & United States & 85.2 \\
14 & ETH Z\"urich -- Swiss Federal Institute of Technology Z\"urich & Switzerland & 84.5 \\
\end{tabular}
\end{document}
Or if you don't want to specify a width or have manual linebreaking, you can use varwidth
\documentclass{article}
\usepackage{array}
\usepackage{colortbl}
\usepackage{xcolor}
\usepackage{varwidth}
\newcolumntype{L}{>{\raggedright\let\newline\\\arraybackslash\hspace{0pt}}}
\newcolumntype{C}{>{\centering\let\newline\\\arraybackslash\hspace{0pt}}}
\cellcolor{black!20}\bfseries\begin{varwidth}[b]{\hsize}\centering\let\newline\\\arraybackslash#1\end{varwidth}}
\begin{document}
\begin{tabular}{cLp{50mm}lr}
\header{Venerable Institution of Higher Eductation} &
1 & California Institute of Technology (Caltech) & United States & 94.9 \\
\multicolumn{4}{c}{\ldots}\\
12 & University of California, Los Angeles (UCLA) & United States & 86.3 \\
13 & Columbia University & United States & 85.2 \\
14 & ETH Z\"urich -- Swiss Federal Institute of Technology Z\"urich & Switzerland & 84.5 \\
\end{tabular}
\end{document}
-
This one avoids the problem in the title by requiring me to manually break my column titles, also in fixed width columns. The embedded tabular makes it easy to do so. Moreover, it is possible to change the alignment to top, middle, bottom, left, right. So it certainly is flexible, and it does the job no matter what the original cell format was. I like it because arguably, it's best to use manual line breaking for long column titles anyway. What I don't like is that this is less true if I want to change formatting for something else than headers! In other words, it's not very generic. – mabartibin Apr 24 '14 at 13:40
@mabartibin well as you say it's a tradeoff, in TeX you always need to either specify a width or linebreak manually (well that's not true if you look at varwidth package but it's true really, varwidth just hides it:-) so you have a choice of manual breaking (and I get the tick) or specifying the width (and egreg gets the tick) but don't do that:-) But you may want to use varwidth package for a generic solution. (I'd manually line break headers anyway) – David Carlisle Apr 24 '14 at 13:59
Well, I think before setting that tick, I'll wait just a little longer to see if someone comes up with a way that is similar to egreg's solution but that can cope with a single macro… – mabartibin Apr 24 '14 at 14:15
@mabartibin varwidth example added – David Carlisle Apr 24 '14 at 15:25
Thank you! But it doesn't do quite the right thing: the headers get centred in their respective varwidth boxes, but not in their columns. – mabartibin Apr 24 '14 at 16:59
Just use a \parbox[b]{\hsize}{...}:
\documentclass{article}
\usepackage{array}
\usepackage{colortbl}
\usepackage{xcolor}
\newcolumntype{L}[1]{%
>{\raggedright\let\newline\\\arraybackslash\hspace{0pt}}%
p{#1}%
}
\multicolumn{1}{>{\bfseries}c}{#1}
}
\parbox[b]{\hsize}{%
\centering\arraybackslash\bfseries\strut#1\strut
}%
}
\begin{document}
\begin{tabular}{cL{50mm}lr}
\rowcolor{black!20}
\fheader{Venerable Institution of Higher Eductation} &
1 & California Institute of Technology (Caltech) & United States & 94.9 \\
\multicolumn{4}{c}{\ldots}\\
12 & University of California, Los Angeles (UCLA) & United States & 86.3 \\
13 & Columbia University & United States & 85.2 \\
14 & ETH Z\"urich -- Swiss Federal Institute of Technology Z\"urich & Switzerland & 84.5 \\
\end{tabular}
\end{document}
-
Thank you! That solves the issue of passing in \hsize. And the trick is that the parbox takes up the whole width of the cell, no matter whether the column was ragged right or left or justified in the first place. But I don't think the same idea can be used for the l/c/r columns, so I still need two header macros? – mabartibin Apr 24 '14 at 13:24
@mabartibin The width of a p column is predetermined; the width of l, c or r columns is not. – egreg Apr 24 '14 at 13:28
sure, I know. And programming a <code>\header</code> macro that inspects <code>\hsize</code> to figure out whether to use <code>vheader</code> or <code>fheader</code> will almost certainly break the <code>\multicolumn</code> again. – mabartibin Apr 24 '14 at 13:42
@mabartibin Use backquotes for surrounding code. \hsize is not set in lcr columns; it will have the same value as outside the tabular. – egreg Apr 24 '14 at 13:46
Oops. I realise that \hsize is not set in lcr. That's what gives me the idea of saving \hsize outside a tabular and checking whether it was reset to figure out if we're in an lcr or pmb column. – mabartibin Apr 24 '14 at 13:54 | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 1, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.5484344959259033, "perplexity": 1507.1987884381456}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 20, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2016-18/segments/1461860111313.83/warc/CC-MAIN-20160428161511-00013-ip-10-239-7-51.ec2.internal.warc.gz"} |
https://nuclearengineering.asmedigitalcollection.asme.org/heattransfer/article/140/5/051301/383917/Deterministic-Phonon-Transport-Predictions-of?searchresult=1 | We present a method for solving the Boltzmann transport equation (BTE) for phonons by modifying the neutron transport code Rattlesnake which provides a numerically efficient method for solving the BTE in its self-adjoint angular flux (SAAF) form. Using this approach, we have computed the reduction in thermal conductivity of uranium dioxide (UO2) due to the presence of a nanoscale xenon bubble across a range of temperatures. For these simulations, the values of group velocity and phonon mean free path in the UO2 were determined from a combination of experimental heat conduction data and first principles calculations. The same properties for the Xe under the high pressure conditions in the nanoscale bubble were computed using classical molecular dynamics (MD). We compare our approach to the other modern phonon transport calculations, and discuss the benefits of this multiscale approach for thermal conductivity in nuclear fuels under irradiation.
## Introduction
One of the fundamental quantities of interest in the safe and efficient operation of nuclear reactors is thermal conductivity $(κ)$ of the fuel, which greatly influences heat transfer throughout the structure of the nuclear core and into the coolant [1,2]. In addition to heat transfer, thermal conductivity is coupled to many other processes in the reactor core. Shifting thermal gradients have a strong influence on the macroscopic cross sections of interaction for neutrons [1]. These cross sections are of high importance since they dictate rates of nuclear fission, neutron absorption, and scattering within the fuel. As temperatures increase, so do the effects of Doppler broadening, which alter neutron scattering and absorption. While this is not a new phenomenon, reactor operators must be keenly aware of the effect temperature has on the absorption and scattering behavior of neutrons. The focus of our work is to develop a predictive computational tool which simulates thermal transport in heterogeneous nuclear fuel in service and under irradiation, with fission product defects.
Thermal conductivity in nuclear fuel is currently obtained through empirical relationships which have been experimentally determined from measurements made during the past 60–70 years [3]. Thermal resistance measurements are performed on nuclear fuel with operating histories, i.e., irradiated fuel and values are obtained at specific temperatures and isotope concentrations. This approach does not consider the constantly changing concentration of isotopic byproducts in the fuel, nor has it historically provided appropriate values across a wide range of reactor operating conditions without significant interpolation error [3,4]. Reactor designers and operators, however, rely on interpolation to fill in the gaps which can be a significant source of uncertainty in predictions of reactor performance. Nuclear reactors are constructed conscious to this attribute and thus have a significant conservatism and safety margin [2].
A better predictive approach to the computation of thermal conductivity could reduce these margins, creating improved performance and economics without compromising safety. A predictive simulation tool could also reduce the reliance on experiment for the development of new fuels for advanced reactors.
Development of nuclear reactors is an ongoing process. The current generation of power reactors is light water moderated and use uranium dioxide $(UO2)$ fuel. In the future, generation IV nuclear reactors will continue to use solid fuel. Uranium-based tristructural-isotropic particles are used in prismatic block high temperature gas reactors, while other fuels such as uranium-molybdenum and uranium-carbide are in development for a plate or pellet-based application [5,6]. Experimental measurements of thermal conductivity will likely be performed on these new fuels, and could result in more empirical correlations used to predict their performance under irradiation. The need for a predictive computational tool to reduce the reliance on destructive thermal conductivity measurements is steadily increasing.
We are developing a deterministic computational framework for simulating phonon transport. When supplied with appropriate information (temperature, isotopic concentration of fission products, and material properties), this framework would predict thermal conductivity in heterogeneous nuclear fuel with an operating history. The fission product significantly hindering thermal transport in UO2 is widely accepted as xenon [7], a noble gas which accumulates in UO2 over its operational life-cycle. The bulk of thermal conductivity characterization is done with molecular dynamics (MD) methodology, which models energy flow explicitly through atomic motion. MD is effective in predicting thermal conductivity, but is only able to model small systems of atoms due to the significant computational cost of the method.
To this end we leverage the code Rattlesnake, which solves a second-order form of the Boltzmann transport equation (BTE) using the self-adjoint angular flux (SAAF) formulation [8] using continuous finite element (CFEM) or discontinuous finite element spatial discretization [9]. Rattlesnake is a member of the multiphysics object-oriented simulation environment (MOOSE) [10] architecture developed and maintained by Idaho National Laboratory. We have shown Rattlesnake may be adapted to simulate phonon transport, and demonstrates promise in connecting transport phenomena at the nanoscale to properties which may be used at the macroscale [11]. We motivate the use of the SAAF formulation of the transport equation and discuss the advantages and disadvantages of the numerical solution of this equation in comparison with solvers for the traditional first-order integro-differential form of the equation.
Our numerical solution technique involves traditional source iteration (SI, a Richardson iteration) methods combined with a robust linear algebraic solver to solve the systems of discretized equations generated by the second-order BTE. With the application of preconditioning, we are able to rapidly solve these systems with tremendous savings in computational cost relative to traditional methods. Additionally, we have the capability to apply nonlinear diffusion acceleration as these simulations become very acoustically thick to yield an even greater convergence acceleration. As such, this approach opens the door for BTE simulation to model heat transport in relatively large systems that contain realistic and statistically representative material microstructures. This approach can potentially become a truly practical and predictive tool to nuclear engineers and material scientists.
## Methods
The generalized BTE is used widely by the transport community. Phonons follow Bose–Einstein statistics in thermodynamic equilibrium and are uncharged like neutrons, which greatly simplifies the mathematical description of their behavior. The BTE for a frequency-dependent phonon distribution $fω$ is
$∂fω∂t+vgΩ·∇fω=f˙ω|scatt$
(1)
For brevity, we have suppressed the independent variables in many of the terms of the equations. The phonon phase space density is $fω=f(r,Ω,ω,p),$ where r is the spatial coordinate $r≡(x,y,z), Ω$ is the unit vector denoting the direction of travel $Ω=(ϕ,θ)$, and ω is angular frequency. p is polarization; the geometrical orientation of phonon travel is transverse in two directions (T) or longitudinal (L). Group velocity vg is related to the propagation speed of phonons, which can have either acoustic (A) or optic (O) modes. However, for this work, we assume a single phonon speed averaged over the acoustic modes and polarizations at varying temperatures, an assumption for the transport of gray phonons which is addressed in Sec. 2.1.
In a steady-state nuclear heat generation environment (nuclear fuel at operating temperatures), we assume no external electrical or magnetic field and Eq. (1) simplifies to
$vgΩ·∇fω=f˙ω|scatt$
(2)
The scattering kernel $f˙ω|scatt$ contains nonlinear operators and includes contributions from processes such as anharmonic phonon interactions or material defect scattering. Other contributions to Eq. (2) can include thermal boundary resistance (TBR) or defect scattering. We use a weak formulation of the phonon transport equation, in which we include upwinding terms to describe the interface condition of TBR, which we develop later.
We apply the single mode relaxation time approximation to simplify the scattering kernel in Eq. (2)—we assume phonons to occupy a single mode, with their scattering contributions collected into a single, effective “relaxation” time, $τeff$ which is on the order of 10−12 s, and describes the response time between phonon scattering events. The kernel is now effectively a measure of the displacement about equilibrium of the phonon distribution function $fω$ [12]
$f˙ω|scatt=fω0−fωτeff$
(3)
here $fω0=fω0(r)$ has been shown to be purely spatially dependent [11]. For small deviations of the phonon distribution function, the scattering term may be expressed by Eq. (3). If a temperature gradient is not present, $fω0−fω=0$ and the scattering term vanishes. In solving for the phonon distribution $fω$ at spatial location $r, fω$ only shifts a small amount from its local equilibrium distribution $fω0$, fixed by the local temperature at r. Substituting Eq. (3) into the right-hand side of Eq. (2) yields
$Ω·∇fω=fω0−fωΛ$
(4)
where vg has been brought to the right-hand side to obtain Λ, the phonon mean free path (the product of group velocity and relaxation time).
### Transport of Gray Phonons.
We apply an isotropic gray approximation to the BTE for phonons, yielding a frequency-independent formulation. This approach combines the contribution to transport from all phonon frequencies and polarizations, and can be averaged into a single effective radiant energy intensity of phonons with a single effective mean free path that accounts for all scattering processes across the phonon frequency spectrum. This is the simplest approach for capturing the ballistic nature of phonon transport over short distances, and provides an adequate description of heat transport physics providing that there is no strong heterogeneity in frequency selective scattering. Equation (5) defines the phonon radiant intensity operator
$M=14π∫0ωlimit∑pvgℏωD(ω)dω$
(5)
and can be applied to a phonon frequency distribution to yield phonon radiant intensity $I(r,Ω̂)$ which has units of $W·m−2·sr−1$. The phonon frequency distribution is multiplied by $vgℏωD(ω)$, summed over all phonon branches and polarizations and integrated over all possible frequencies (limited by the vibrational frequency of the medium). Here, $ℏ$ is the reduced Planck's constant, and $D(ω)$ is the phonon density of states.
Operating on Eq. (4) with $M$ yields
$ΛΩ·∇I(r,Ω)=I0(r,Ω)−I(r,Ω)$
(6)
Equation (6) is the equation of phonon radiative transfer (EPRT) [13]. The allure of the gray phonon EPRT is that the consequences of ballistic transport between geometric scattering features are determined explicitly but the entirety of the local intrinsic and extrinsic scattering physics is lumped into a single parameter that may be obtained empirically, from first principles, or some hybrid mixture of both. The next level of approximation is to model transport explicitly including the spectrum of participating phonon frequencies.
The central limitation of the gray approach is its inability to model transport in anisotropic materials or across strongly frequency selective boundaries. Further refinement includes modeling frequency-dependent transport across the phonon spectrum, but to still treat collision terms through the single relaxation approximation. From the point of view of our efficient SAAF solution method, the two approaches are numerically identical with independent equations coupled only through a single integral term. For simplicity of demonstrating the SAAF approach, we limit the scope of this work to the gray phonon model. While we have chosen to demonstrate the effectiveness and efficiency of our numerical approach in the context of frequency-independent transport, the extension to the solution of the frequency-dependent BTE with the relaxation time approximation is trivial since frequency appears as a parameter in the equation, i.e., the solution in each frequency group is decoupled from all other groups.
### Self-Adjoint Form of the Phonon BTE.
Morel and McGhee [8] outline an algebraic technique for the derivation of the self-adjoint form of the neutron transport equation. From a computational perspective, the SAAF formulation is advantageous, since the full angular flux becomes the unknown. Using reflecting boundary conditions becomes easier with the availability of the full angular flux, as the incoming and outgoing directions are coupled in the same manner as the first-order form of the transport equation. Through the application of a CFEM spatial discretization, the matrices are symmetric positive definite, which allows for the use of solution techniques such as the preconditioned Krylov family of solvers [10]. The MOOSE framework uses CFEM as a spatial discretization and by default employs Jacobian-free Newton Krylov [14] with preconditioning as a nonlinear iterative solution method.
Through a straightforward algebraic technique, the phonon BTE may be manipulated into the SAAF formulation. Solving Eq. (6) for $I(r,Ω̂)$ yields
$I(r,Ω)=I0(r,Ω)−ΛΩ·∇I(r,Ω)$
(7)
Substituting Eq. (7) back into Eq. (6), distributing and collecting like terms gives the SAAF form of the EPRT. The self-adjoint component of Eq. (8) is the second term, which contains a second-order operator and is symmetric positive definite
$−Ω·∇[ΛΩ·∇I(r,Ω)]+1ΛI(r,Ω)=−Ω·∇I0(r,Ω)+1ΛI0(r,Ω)$
(8)
From Eq. (8), the change in the phonon intensity at a point has two contributions: a streaming term from the spatial variation in intensity, and a collision term due to the deviation of the radiance from the equilibrium phonon radiance $I0(r)$. Due to the implication of the single mode relaxation time approximation, the phonon radiative equilibrium intensity will be defined with a condition of zero heat generation, $∇·q=0$. This suggests that a phonon radiative equilibrium could exist at all possible frequencies and provides some justification for the gray media formulation [13].
We employ two forms of boundary condition in this work: radiant emitting boundaries and reflecting boundaries. The angular phonon radiance at an emissive boundary may be defined as
$Ib(r,Ω)=CvvgTb4π$
(9)
where Tb is a constant driving boundary temperature. For reflecting conditions, outgoing angular phonon radiance is defined as the reflection of the incoming angular phonon radiance, merely undergoing a directional change, i.e., $I(r,Ω)=I(r,Ω′)$ where we map $Ω$ to $Ω′$.
The angular variable $Ω$ is discretized via the discrete ordinates method, sometimes referred to as the “SN method.” The transport equation becomes a set of N equations for the radiant intensity in each discrete angle. Solutions to the EPRT generate angular phonon radiative intensity, and Rattlesnake employs level-symmetric quadrature to numerically integrate this quantity over solid angle, to obtain “moments” of the radiance. The SN method has advantages in heterogeneous media over the spherical harmonics method $(PN)$, in that the $PN$ angular moments are tightly coupled, and their solution requires more computational resources [15]. The recent application of a hybrid $SN−PN$ scheme to discretize the angular variable in the frequency-dependent phonon BTE has been shown to exhibit slow convergence in homogeneous silicon [16] which suggests that the PN angular discretization approach may not be optimal for this type of problem.
The discrete ordinates SAAF transport equation has the feature that in each quadrature direction, a linear system of equations arising from the spatial discretization of an elliptic operator is solved for the angular intensity. This means that software for solving the diffusion approximation to transport can be readily converted to solve the transport equation. The treatment of voids and certain boundary conditions require special care, however. In contrast, the solution of the first-order form of the transport equation involves transport “sweeps” [15], where incident intensities from the problem boundary, and interior sources along the way, are propagated through the spatial mesh along the direction of travel to the exiting mesh boundary. The ordering of this mesh sweep is angle and problem dependent, and in multiple dimensions cyclic graphs are possible. Developing sweep algorithms that scale to large numbers of processors is an active research area, whereas efficient parallel solvers for elliptic equations are much more mature.
The zeroth angular moment of phonon radiance $I(r)$ is proportional to temperature, phonon speed, and volumetric specific heat capacity
$∫4πI(r,Ω)dΩ=CvvgT4π$
(10)
The first angular moment is the heat flux
$q(r)=∫4πI(r,Ω)Ω dΩ$
(11)
Other researchers have taken different approaches to computing heat flux, incorporating quantities obtained through MD simulations (phonon group velocity, wave vectors, and angular frequencies [1719]).
We compute an effective thermal conductivity by taking the ratio of the average heat flux to the end-to-end temperature gradient (which includes effects at the boundaries) in the system
$⟨κeff,z⟩=∫ez·q(r)d3r∫ez·∇T(r)d3r$
(12)
Though heat flux and temperature gradient are computed over the entire domain, the dimension of interest is one where a temperature gradient is applied. This methodology is used in MD simulations and is repeated here.
### A Test Problem.
To evaluate the effectiveness of Rattlesnake as a deterministic transport engine, we compared our numerical solutions of temperature and thermal conductivity in room temperature, homogeneous silicon to the work of Yilbas and Bin Mansoor, who performed deterministic phonon transport simulations in silicon under equivalent conditions [20]. They used a forward and backward finite difference discretization scheme to solve the BTE for phonons.
Yilbas and Bin Mansoor modeled a thin film of silicon, a common configuration which is used in many phonon transport simulations (with both deterministic and Monte Carlo methodologies) as a benchmark problem. Material properties of room temperature silicon are well known, and transport behavior at the nanoscale has been studied [13]. Material properties for this model were obtained from the open literature [13,21], and are listed in Table 1.
Table 1
Silicon material data
ParameterValue
$Cv (J·m−3·K−1)$$1.653×106$
$vg (m·s−1)$8430
$Λ (m)$$33.9×10−9$
$TL (K)$301
$TR (K)$300
ParameterValue
$Cv (J·m−3·K−1)$$1.653×106$
$vg (m·s−1)$8430
$Λ (m)$$33.9×10−9$
$TL (K)$301
$TR (K)$300
We construct a finite element mesh for a cube of silicon with side lengths of $3Λ$ (equivalent to 3 acoustic lengths) using CUBIT [22] with both a coarse and fine mesh of 1000 and 12,000 hexahedral elements, respectively. We apply a temperature difference of 1 K to the yz planar boundaries to simulate phonon emission sources and placed reflecting boundary conditions on the remaining planes. We define the nondimensional temperature Θ as
$Θ=T(x)−TRTL−TR$
(13)
We use the generalized minimum residual [23] method preconditioned with algebraic multigrid [24] to solve the linear system, with an iterative convergence criteria of $ϵ=10−6$, and an S8 angular quadrature. Computation times for coarse and fine mesh cases were approximately 8 and 57 s each. Simulations were performed on a single core 2.8 GHz Intel i7 CPU with 16 GB RAM. The coarse and fine mesh solutions are within 10−5 of each other; for simulations of homogeneous media, it may be appropriate to use a more coarse spatial mesh to decrease computation time. The behavior of the nondimensional temperature solution for coarse and fine mesh cases obtained with Rattlesnake agree well with those from Yilbas and Mansoor, shown in Fig. 1. The temperature profile has a slight curvature, which is influenced by spatial discretization. Improperly scaled finite elements do not produce the desired solution behavior. As the acoustic thickness increases, phonon scattering regimes shift from ballistic to diffuse. In an acoustically thin medium, where $L≈Λ$, phonons leaving a colder boundary are in the ballistic scattering regime, and propagate far across the medium to reach the hotter boundary causing the material temperature to be smaller than that associated with the prescribed incident intensity. In an acoustically thick medium, where phonons are in the diffuse scattering regime, this effect is significantly diminished. These are boundary scattering effects and are well characterized in simulations of phonon transport [13,20].
Fig. 1
Fig. 1
Close modal
## Uranium Dioxide With Xenon Bubble
Du et al. [7] investigated the effects of xenon presence on thermal conductivity of UO2. MD methods were used to simulate the effect of various concentrations and geometric configurations of xenon in the UO2 lattice for a range of temperatures. They concluded that randomly dispersed xenon in the fuel matrix has a more significant impact on thermal conductivity than quantized xenon bubbles. At higher temperatures, phonon–phonon scattering from normal and Umklapp processes becomes a main contributor to the suppression of thermal conductivity, and heat transport is locally disrupted at the xenon defect. The phonon mean free path $(Λ)$ in UO2 becomes shorter at high temperature and diffuse scattering dominates. Xenon concentration was limited to about 1% of volume in the simulations.
We model a selected problem from Du et al., computing temperature, heat flux, and thermal conductivity in a cell of UO2 with a bubble of xenon in the center, in the absence of grain boundaries. The behavior of xenon in a UO2 lattice at high temperature and pressures has been reported to vary widely, and available experimental data are minimal. Computational studies have been performed to investigate expected temperatures and pressures of xenon using various methodologies which drew varying conclusions [2527]. We performed MD simulations to determine the properties of xenon at specific pressure and temperatures; these data are used to compute Λ in the bubble. Bates [28] performed thermal conductivity measurements on stoichiometric, unirradiated UO2 for a large array of temperatures. We extract Λ from measured thermal conductivity in the Bates study, and perform simulations using the same bubble geometry to determine the impact of xenon on κ using values of Λ from Bates. We compare these results to the bulk κ of pristine UO2 measured by Bates and to κ computed using parameters from Du et al.
The role of thermal boundary resistance at the UO2–Xe interface is investigated, as incoming delocalized waves may reflect diffusely or specularly off the xenon bubble and have a significant effect on the local thermal conductivity. We introduce the diffuse mismatch model (DMM) and present a method to characterize thermal boundary resistance at heterogeneous defects in three-dimensional (3D).
### Problem Description.
We use Rattlesnake to simulate phonon transport in a cell of UO2 with a xenon bubble in the cell center and no grain boundaries. The spatial domain $D$ is a rectangular cell, 25 nm along the z-axis with a cross section of 3.8 nm × 3.8 nm, consistent with the geometry used by Du et al. The xenon bubble has a radius of 1 nm and accounts for approximately 1% of the total volume. The finite element geometry is constructed with CUBIT, an unstructured mesh consisting of 100,689 tetrahedral elements (Fig. 2). The linear system is solved with the algebraic multigrid-preconditioned generalized minimum residual method with convergence criteria of $ϵ=10−6$. We performed simulations with an angular quadrature order of S24, a large amount of ordinates helps to mitigate ray effects [29], which can occur in deterministic phonon transport simulations.
Fig. 2
Fig. 2
Close modal
Du et al. reported κ in UO2 with Xe at 300 K, 800 K, and 1500 K. Where possible, we replicate their simulation conditions and report dimensionless temperature, heat flux, and thermal conductivity. We extract Λ from values of thermal conductivity for unirradiated UO2 as documented by Du et al. In each simulation, a 1 K temperature difference is applied along the z-axis. We use the same mesh to perform additional simulations for different values of temperature using Λ extracted from experimental values of thermal conductivity measured by Bates [28]. Simulations using the mean free path from Bates are performed independently of the Du et al. simulations, in order to gain insight into the effect Λ has on overall heat flux, temperature gradient, and thermal conductivity.
### Material Properties.
The only material property entering into the gray BTE in Eq. (8) is the phonon mean free path, Λ, and so we need to determine these for UO2 and Xe. However, it is also necessary to determine each material's phonon radiance, $I0(T)$, as a function of temperature in order to impose the correct scalar flux at the external boundaries, and to set the transmission coefficients at the internal boundary.
To set the effective mean free path for the gray phonons in both the UO2 and Xe we use the standard kinetic equation for thermal conductivity [12]
$κ=13CvvgΛ$
(14)
For the UO2, vg and Cv of acoustic modes are computed from first principles calculations, and then Λ is chosen so as to reproduce the experimentally measured values of κ in unirradiated UO2 [28]. The calculation of vg and Cv in UO2 is described in detail in Sec. 3.2.1. For Xe, the κ, vg, and Cv are computed from classical molecular dynamics simulations, and similarly used to infer Λ in the Xe.
The effective group velocity and effective mean free path of the gray phonons were assumed to be isotropic in both the UO2 and the Xe. In order to understand the degree to which transport is ballistic in either region we consider the acoustic thickness, ζ, in each domain. This is the domain size scaled by the material's effective phonon mean free path. Acoustic thickness of UO2 is the ratio $ζUO2=DUO2,z/ΛUO2$, where $DUO2,z$ is the distance between the hot and cold sides of the UO2 cell. Similarly, the acoustic thickness of the Xe, $ζXe=DXe/ΛXe$, describes the diameter of the bubble relative to the effective (gray) phonon mean free path in Xe; acoustic data and mean free path for simulations using values from Du et al. are contained in Table 2.
Table 2
Mean free path data for pristine UO2 [7] and Xe (this work)
$T(K)$$ΛUO2 (nm)$$ΛXe (nm)$$ζUO2$$ζXe$
30031.91.100.781.82
80014.30.771.752.6
15007.60.83.32.5
$T(K)$$ΛUO2 (nm)$$ΛXe (nm)$$ζUO2$$ζXe$
30031.91.100.781.82
80014.30.771.752.6
15007.60.83.32.5
The transport properties of Xe are strongly tied to the Xe pressure, which in turn is set by the surface tension of the UO2/Xe interface and the bubble size. In a 2 nm diameter bubble of Xe in UO2, the pressure is estimated to be between 2 and 5 GPa, and so in this work, the Xe pressure was assumed to be 3 GPa at all temperatures studied. At this pressure, Xe is either solid or liquid across the temperature range that we study here, and so the use of a gray phonon model of transport is justified in the Xe. Across the range of temperatures we study, we hold the size of the bubble fixed (with radius of 1 nm), meaning that as the temperature is changed the number of Xe atoms in the bubble is not constant. This means that our sweep of simulations does not represent the change in thermal conductivity due to heating UO2 containing Xe bubbles from 300 to 1500 K. However, it does provide us insight into the ballistic versus diffusive contributions to thermal resistance from 1 nm bubbles at different temperatures.
#### UO2 Calculations.
For UO2, the effective group velocity, volumetric specific heat, and radiance of gray phonons was computed by averaging the properties of the three acoustic branches of the phonon dispersion over the entire Brillouin zone. The phonon dispersion was computed on a 50 × 50 × 50 q-point grid using Phonopy [30] based on the structure symmetry of UO2 (Fd-3m) with interatomic force constants computed from first principles. The UO2 simulations were executed with the plane-wave basis projector augmented wave method within the density functional theory framework as implemented in the Vienna ab initio simulation package [3133]. A plane-wave energy cutoff of 600 eV was employed in the local density approximation [34], with a 6 × 6 × 6 Monkhorst-Pack k-point grid. A $2×2×2$ super-cell of the UO2 unit cell (with 4 O and 8 U atoms) was used for all calculations, including calculation of the force constants. The perfect super-cell was found to be relaxed to a $1×10−3 eV/Å$ ionic tolerance and a $1×10−5$ eV electronic tolerance. UO2 is antiferromagnetic, but there exist ferromagnetic solutions to the Kohn–Sham equation, and Vienna ab initio simulation package can get trapped into a ferromagnetic state. To prevent this from happening, the magnetic moment tag was selected to ensure that alternating uranium atoms in the structure had opposing spins, and the spin of the oxygen atoms was set to zero. We further used a Hubbard parameter, U, of 4.50 eV, and a Hund's exchange parameter, J, of 0.50 eV. The resulting electronic density of states (Fig. 3) agrees with that of Wang et al. [35]. The phonon dispersion (Fig. 4), also in good agreement with that obtained in the same reference [35].
Fig. 3
Fig. 3
Close modal
Fig. 4
Fig. 4
Close modal
The effective transport properties of the gray phonons in UO2 were computed from the following expressions:
$I0(T)=14π∑p=13∫BZdk3|νg(p,k)|2π3a3ℏω(p,k)nBE(ω(p,k),T)$
(15)
where $nBE(ω,T)$ is the Bose–Einstein distribution, a is the lattice parameter of UO2, and p is the phonon polarization. The volumetric specific heat capacity is computed using a similar integral
$Cv=12π3a3∑p=13∫BZdk3ℏω(p,k)∂nBE(ω(p,k),T)∂T$
(16)
Using these integrated quantities, we can define an effective group velocity for gray phonons as
$vg(T)=4πI0(T)CvT$
(17)
This velocity and the heat capacity are only very weakly temperature dependent over the temperature range of interest, and thus, we approximate it by their average values of $1764 m·s−1$ and $1.007×106 J·m−3·K−1$, respectively. Note that this effective velocity of the gray phonon bath is approximately 0.45 of the mean speed of sound obtained from the same UO2 calculations. It is in effect the average group velocity of acoustic phonon modes weighted by the thermal energy in the mode. Similarly, the effective specific heat is not the true specific heat of UO2, but only the contribution to its specific heat from the acoustic modes and the computed value for this is is close to the high temperature limit for the acoustic modes of $12kB/a3$.
#### Xenon Calculations.
The thermal conductivity and transport properties of xenon under high pressure were computed from classical molecular dynamics simulations performed using the large-scale atomic/molecular massively parallel simulator package [36]. Interatomic forces were modeled using a Lennard–Jones potential with large-scale atomic/molecular massively parallel simulator parameters $ϵ=0.00425 eV$ and $σ=4.29 Å$, with all interactions truncated after $20 Å$.
Simulated systems of 10,000 Xe atoms under 3 GPa were prepared at a series of temperatures from 300 to 1700 K. This was achieved by equilibrating the system over a 500 ps simulation in the constant number of atoms, pressure, temperature ensemble before turning of the thermostat and barostat and simulating for a further 50 ps in the microcanonical ensemble. In these simulations, it was found that the Xe was solid at temperatures below $∼600$ K, and above that, remains liquid up to $1700 K$. Once the systems were prepared, the system was simulated in for a further 1 ns in the microcanonical (NVE) ensemble, during which the thermal conductivity was computed using the Green–Kubo method [37]. The Green–Kubo method is founded on the fluctuation dissipation theorem to determine the thermal conductivity of a system from the lifetime of its natural thermal fluctuations during a simulation of the system at equilibrium. A minimum of six simulations were performed using different random starting configurations and the results averaged to obtain each thermal conductivity datum.
For vg of Xe, we use the speed of sound computed at each temperature from the Xe's density and isentropic compressibility. The isentropic compressibility was computed by simulating adiabatic expansion. At each temperature, the system was first cycled in an NVE ensemble after which system dimensions were slightly increased, followed by another NVE cycling step. The compressibility was calculated from the differences in system volume and pressure before and after expansion. This set of simulations also served as the source of density data. The Xe density was also used to compute Xe's volumetric specific heat capacity at each temperature.
The computational approach for determining both thermal conductivity and speed of sound were validated by computing the pressures at slightly lower pressures for which there exists experimental data [38] and finding the properties to be in reasonable agreement. The computed density, thermal conductivity, vg, and $ΛXe$ are plotted in Fig. 5, and clearly show a transition in properties between the solid and liquid Xe.
Fig. 5
Fig. 5
Close modal
### Thermal Boundary Resistance.
We must consider the resistive effect at material interfaces: the phenomenon of TBR, the ratio of a temperature discontinuity at an interface to the heat flux across that interface, due to a material difference at the junction. TBR is an extraordinarily subtle phenomenon and has some consideration in other deterministic phonon transport studies [39,40]. However, it is very important to consider in simulating phonon transport, and has been characterized in a number of other MD and Monte Carlo studies [4143].
The physics of TBR are important to phonon transport because of how phonons behave when they encounter a physical interface between two adjacent materials. At this junction, phonons become subject to a phenomenon which manifests as a transmissive and resistive effect for phonons penetrating an interface into another material. This physical effect occurs as the intrinsic properties of material change. Phonons define the internal energy of a material; when they cross a boundary from one material into the next, the change in their contribution to internal energy as well as change in their velocity must be considered.
We develop the DMM [44] in a deterministic framework for 3D general geometries. We assume all phonons are diffusely scattered at the interface, with outgoing radiance emitted isotropically, and that scattering destroys the correlation between the wavevectors of incident and outgoing phonons; the probability that a phonon will scatter into a given side of the interface is independent of the phonon origin. Enforcing these conditions makes the probability of scattering into a given side proportional to the phonon density of states on that side, additionally constrained by the principle of detailed balance.
We can write a balance equation for the flow of phonons between two materials
$Uαvg,αTα→β=Uβvg,βTβ→α$
(18)
where $Uα, Uβ, vg,α, vg,β$ are internal energies and phonon speeds of materials α and β, respectively. We define $Tα→β$ as the probability of transmission from material α into material β, and $Tβ→α$ as the probability of transmission from material β into material α. It follows that
$Tα→β+Tβ→α=1$
(19)
to uphold conservation of energy and detailed balance. We solve for the transmission probabilities, which are
$Tα→β=Uβvg,βUαvg,α+Uβvg,β$
(20)
$Tβ→α=Uαvg,αUαvg,α+Uβvg,β$
(21)
it follows that the probabilities of reflectance are defined as $Rα→α=1−Tα→β$ and $Rβ→β=1−Tβ→α$, where $Rα→α$ is the reflectance of phonons in material α incident on the interface back into material α, and $Rβ→β$ is the reflectance of phonons in material β incident on the interface back into material β.
We take the first-order form of the steady-state, frequency-independent phonon transport equation to derive balance relations for phonons incident on and leaving a spatially discontinuous interface
$Ω·∇I(r,Ω)+1ΛI(r,Ω)=1ΛI0(r)$
(22)
In Fig. 6, we denote “−” as the upwind radiant flux and “+” as the downwind radiance. The scalar radiance is identified by $Iα;β±(rint)$. We must solve for the upwind and downwind scalar radiance at the interface $rint$ to characterize the effects of TBR in our transport simulation. In the transport equation, we solve for the angular radiance, which is integrated over solid angle to solve for scalar radiance.
Fig. 6
Fig. 6
Close modal
At the location $rint$ with its unit vector normal to the interface which points from material α to material β denoted as $nα→β$, we can write conservation equations which define the flow of phonons immediately at both sides of the interface. On the β side of the interface, phonons which flow away from the interface into material β come from two sources: they are transmitted through the interface from material α, and reflected from those incident on the surface from the β side.
On the β side of the interface, each angular radiance corresponding to a particular ordinate $Ωm$ is assigned the new diffuse flux, an angular redistribution of the transmitted portion of phonons from side α and reflected phonons from side β. This diffuse flux is now the effective source of phonons flowing away from the interface into material β. An analogous procedure holds for phonons flowing into material α. We identify the new flux with its contributions from α and β side phonons as $Iα;β(rint±)$. The conservation equation expressing the flow of phonons away from the interface into material α is then developed as
$∫nα→β·Ω̂>0I(rint+,Ω)|nα→β·Ω|dΩ=Iβ(rint+)∫nα→β·Ω>0|nα→β·Ω|dΩ=Tα→β∫nα→β·Ω>0I(rint−,Ω)|nα→β·Ω|dΩ+Rβ→β∫nα→β·Ω<0I(rint+,Ω)|nα→β·Ω|dΩ$
(23)
such that we solve for the downwind diffuse radiance flowing into material β from material α
$Iβ(rint+)=1∫nα→β·Ω>0|nα→β·Ω|dΩ×[Tα→β∫nα→β·Ω>0I(rint−,Ω)|nα→β·Ω|dΩ+Rβ→β∫nα→β·Ω<0I(rint+,Ω)|nα→β·Ω|dΩ]$
(24)
A similar expression describes the upwind diffuse radiance of phonons flowing from material β into material α. These new expressions for the scalar radiance are now the isotropic emission sources on either side of the interface and are distributed at each direction of outgoing angular radiance at the interface $Iα;β(rint±,Ω)$.
The effective implementation of this model allows for the description of localized heat flux and temperature around defects in heterogeneous structures. The DMM is a relatively crude descriptor of TBR, an improved model of interface physics would necessitate the inclusion of anharmonic effects, and would also need to be adaptive to phonon frequency selection over the interface itself [45]. We computed transmission and reflection coefficients for UO2 and Xe from the material properties determined in Secs. 3.2.1 and 3.2.2; these are shown in Fig. 7. At all temperatures, the phonon radiance is approximately two orders of magnitude larger in the UO2 than in the Xe; the boundary is highly resistive to phonons flowing from UO2 into the Xe bubble with approximately 40% transmitted at 300 K, decreasing sharply as temperature increases.
Fig. 7
Fig. 7
Close modal
### Results and Discussion.
We report simulated heat flux and thermal conductivity for an array of temperatures with two sets of values for $ΛUO2$; one generated from the MD results of Du et al. (denoted $ΛDu$), the other extracted from experimentally measured values of κ in unirradiated samples of UO2 from Bates (denoted $ΛBates$). In both cases, we use material properties for Xe based on MD simulations we performed, as well as the same spatial mesh. We observe the effects of thermal boundary resistance at the Xe bubble, which play a role in the amount of overall thermal resistance the bubble provides. In all cases, the presence of xenon lowers the thermal conductivity in the UO2.
Figure 8 shows all values of simulated κ and the measured pristine κ. In the upper half of Fig. 8, we compare to Bates and follow a similar trend showing decreased thermal conductivity with increasing temperature. This is further affected by the presence of the xenon bubble; κ is reduced by approximately 30–55% over the temperature range with the sharpest difference occurring at lower temperature.
Fig. 8
Fig. 8
Close modal
In the lower half of Fig. 8, we compare our κ to that of Du et al.; while we follow a loose trend in the shape of the curve, we experience a large discrepancy in simulated values. We under-predict κ in simulations with and without a Xe bubble, which may have multiple causes. Numerical results of κ from this study are compared to those of Du et al. in Table 3. Our computed group velocity in UO2 is lower by approximately a factor of 2 compared to Du et al.; it is no surprise that our κ with Xe is also lower by approximately the same factor. We justify this exclusively for a gray approach in that we assume all phonons do not travel at the speed of sound in UO2; indeed from the calculations in Sec. 3.2.1 it is clear that the group velocity is averaged, but has contributions from phonons with varying Λ lumped into a single term. Some phonon modes may be highly sensitive to frequency, and this detail is washed out in the gray approach. This assumption may explain some of the underestimation in the ballistic effects. In addition, we may not be capturing some intrinsic phonon scattering, and we currently do not have anharmonicity built into the relaxation time; there is no way to discern these effects. The relaxation time $τeff$ has many contributions: Umklapp processes, defect scattering, boundary scattering, and the resonant scattering of phonons. Classic MD can be used to characterize many of these processes, but MD is not able to capture certain quantum effects at low temperatures, such as specific heat [46], and this may be a reason for the discrepancy.
Dimensionless temperature for all simulated temperature is shown in Fig. 9. The influence of the xenon bubble is clear, and jumps at the interface are observed; these are more pronounced at lower temperatures when phonon scattering is highly ballistic. This effect results in localized negative temperature gradients, which was also observed by Yang in Si nanowires [43], and the gradient monotonically shifts toward zero with increasing temperature. Note that while the temperature gradient becomes negative, the net flux in this region is still positive (see Fig. 10)—heat is apparently flowing uphill. This result is counterintuitive when thinking of heat flow in the diffusive limit, but is entirely consistent with a ballistic picture of transport in which the energy of the phonon gas at any point contains nonlocal information.
Fig. 9
Fig. 9
Close modal
Fig. 10
Fig. 10
Close modal
The centerline heat flux $q(r)$ shown in Fig. 10 has been normalized to the 300 K value; $q(r)$ is inversely proportional to temperature and experiences a steady decline as temperatures increase. As temperature increases, $ΛUO2$ decreases and diffuse scattering becomes more prevalent, which contributes to the reduction in heat flux. As a result of TBR, large portions of the phonon radiance are reflected at the xenon bubble, decreasing local $q(r)$ by resisting the flow of phonons.
Heat flux in the UO2 region remains approximately constant along the temperature gradient and changes drastically at the Xe bubble. We observe this effect in Figs. 10 and 11, where heat flux is severely depressed in the region local to the Xe bubble. The presence of a single xenon bubble does not significantly impact average $q(r)$ in the domain, but it does affect the behavior of the local heat flux. Du et al. established this by performing MD simulations which include multiple Xe bubbles and Xe randomly dispersed in the UO2 matrix [7]. Ray effects are observed at lower temperatures when phonon scattering is highly ballistic (slight oscillations in $q(r)$) but vanish as scattering becomes diffuse. With increasing temperature, the heat flux is gradually suppressed, and the effects of Xe on the local heat flux become less significant. $ΛUO2$ decreases by approximately a factor of 3 between the temperature extremes, and this decrease is more detrimental to heat flux than compared to the presence of a singular bubble of Xe. Additional Xe bubbles would have a greater negative effect on bulk thermal conductivity.
Fig. 11
Fig. 11
Close modal
Table 4 contains the total number of source iterations required for convergence, and total acoustic thickness of the spatial domain over the range of temperatures. As ζ increases, required iterations decrease; this is counterintuitive as purely scattering thermal radiation and phonon transport simulations tend to require more iterations for convergence with increasing ζ. This effect is potentially related to the oscillations experienced in the ballistic scattering regime, where Λ is on the order of the entire spatial domain (Casimir limit).
Table 3
Thermal conductivity $(W·m−1·K−1)$ simulated using $ΛUO2$ [7]
$T(K)$Pristine $UO2$ [7]$UO2+Xe$ [7]$UO2+Xe$
30015.9711.645.3
8007.816.973.8
15004.294.062.6
$T(K)$Pristine $UO2$ [7]$UO2+Xe$ [7]$UO2+Xe$
30015.9711.645.3
8007.816.973.8
15004.294.062.6
Table 4
Iteration details: linear iterations and acoustic thickness ζ for simulation using $ΛBates$
$T(K)$Source its.$ζUO2+ζXe$
3001163.4
500854.2
800826.3
1000766.8
1100797.2
1200777.5
1300757.8
1400758.2
1500768.5
$T(K)$Source its.$ζUO2+ζXe$
3001163.4
500854.2
800826.3
1000766.8
1100797.2
1200777.5
1300757.8
1400758.2
1500768.5
## Conclusions
We have presented the features of a 3D, generalized geometry radiation transport code modified to simulate phonon transport in a gray formulation. We have implemented the physics for thermal boundary resistance in 3D to describe phonon transport behavior at localized defects in the material. We have presented our deterministic transport results for a simulation of a 3D domain of UO2 with a Xe impurity and compared them against MD results for similar geometry and simulation parameters [7]. Additionally, we use $ΛUO2$ extracted from experimentally measured pristine UO2 for the same simulation setup, and mimic the shape of the κ curve in Ref. [28] but with lower values of κ due to the Xe presence.
The transport method we have presented is trivially extendable to simulate a multifrequency phonon spectrum using input variables derived from density functional theory (DFT) simulations, consistent with our discussion in this work (Secs. 3.2.1 and 3.2.2). The use of deterministic methods to simulate phonon transport is an underdeveloped aspect of the phonon transport community. Classical molecular dynamics simulations and DFT electronic structure calculations can provide detailed information about material properties, dispersion relations, and thermal conductivity but do so only at a local or nanometer scale. It is well understood that resistive processes also arise from the mesoscale structure of materials and these cannot be captured efficiently from atomistic calculations (a point that is reinforced by the results in this work).
By coupling Rattlesnake to MD and DFT methodologies, we show a way to bridge the gap between the atomistic and engineering scales. This multiscale method provides a framework for rapid prediction of the engineering-scale thermal conductivity in materials with evolving microstructures. Such a tool is particularly imperative for modeling nuclear fuels and their surrounding structural materials in which the thermal conductivity of the materials is a central component of the system performance.
## Acknowledgment
We acknowledge Idaho National Laboratory for their support and thank Sebastian Schunert, Yaqi Wang, and Daniel Schwen for their valuable assistance. We also thank David Andersson of Los Alamos National Laboratory for providing MD data for comparison. For the DFT and MD simulations, this work used the Extreme Science and Engineering Discovery Environment (XSEDE).
## Funding Data
• National Science Foundation (Grant No. ACI-1548562).
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,
C.
, and | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 155, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.8798667788505554, "perplexity": 1435.8541632648385}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 20, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2022-33/segments/1659882573163.7/warc/CC-MAIN-20220818033705-20220818063705-00316.warc.gz"} |
https://es.mathworks.com/help/ident/ref/etfe.html | # etfe
Estimate empirical transfer functions and periodograms
## Syntax
``g = etfe(data)``
``g = etfe(data,M)``
``g = etfe(data,M,N)``
## Description
example
````g = etfe(data)` estimates a transfer function of the form: $y\left(t\right)=G\left(q\right)u\left(t\right)+v\left(t\right)$`data` contains time- or frequency-domain input-output data or time-series data:If `data` is time-domain input-output signals, `g` is the ratio of the output Fourier transform to the input Fourier transform for the data. For nonperiodic data, the transfer function is estimated at 128 equally-spaced frequencies `[1:128]/128*pi/Ts`.For periodic data that contains a whole number of periods (```data.Period = integer``` ), the response is computed at the frequencies `k*2*pi/period` for ```k = 0``` up to the Nyquist frequency.If `data` is frequency-domain input-output signals, `g` is the ratio of output to input at all frequencies, where the input is nonzero.If `data` is time-series data (no input channels), `g` is the periodogram, that is the normed absolute square of the Fourier transform, of the data. The corresponding spectral estimate is normalized, as described in Spectrum Normalization and differs from the `spectrum` normalization in the Signal Processing Toolbox™ product.```
example
````g = etfe(data,M)` applies a smoothing operation on the raw spectral estimates using a Hamming Window that yields a frequency resolution of about `pi/M`. The effect of `M` is similar to the effect of `M` in `spa`. `M` is ignored for periodic data. Use this syntax as an alternative to `spa` for narrowband spectra and systems that require large values of `M`. ```
example
````g = etfe(data,M,N)` specifies the frequency spacing for nonperiodic data.For nonperiodic time-domain data, `N` specifies the frequency grid `[1:N]/N*pi/Ts` rad/TimeUnit. When not specified, `N` is 128.For periodic time-domain data, `N` is ignored.For frequency-domain data, the `N` is `fmin:delta_f:fmax`, where `[fmin fmax]` is the range of frequencies in `data`, and `delta_f` is `(fmax-fmin)/(N-1)` rad/TimeUnit. When not specified, the response is computed at the frequencies contained in data where input is nonzero.```
## Examples
collapse all
`load iddata1 z1;`
Estimate empirical transfer function and smoothed spectral estimate.
```ge = etfe(z1); gs = spa(z1);```
Compare the two models on a Bode plot.
`bode(ge,gs)`
Generate a periodic input, simulate a system with it, and compare the frequency response of the estimated model with the original system at the excited frequency points.
Generate a periodic input signal and output signal using simulation.
```m = idpoly([1 -1.5 0.7],[0 1 0.5]); u = iddata([],idinput([50,1,10],'sine')); u.Period = 50; y = sim(m,u);```
Estimate an empirical transfer function.
`me = etfe([y u]);`
Compare the empirical transfer function with the original model.
`bode(me,'b*',m,'r')`
Perform a smoothing operation on raw spectral estimates using a Hamming Window and compare the responses.
`load iddata1`
Estimate empirical transfer functions with and without the smoothing operation.
```ge1 = etfe(z1); ge2 = etfe(z1,32);```
Compare the models on a Bode plot.
`ge2` is smoother than `ge1` because of the effect of the smoothing operation.
`bode(ge1,ge2)`
Estimate empirical transfer functions with low- and high-frequency spacings and compare the responses.
`load iddata9`
Estimate empirical transfer functions with low and high frequency spacings.
```ge1 = etfe(z9,[],32); ge2 = etfe(z9,[],512);```
Plot the output power spectrum of the two models.
`spectrum(ge1,'b.-',ge2,'g')`
## Input Arguments
collapse all
Estimation data, specified as an `iddata` object. The data can be time- or frequency-domain input/output signals or time-series data.
Frequency resolution, specified as a positive scalar.
Frequency spacing, specified as a positive scalar. For frequency-domain data, the default frequency spacing is the spacing inherent in the estimation data.
## Output Arguments
collapse all
Transfer function estimate, returned as an `idfrd` model.
Information about the estimation results and options used is stored in the model's `Report` property. `Report` has the following fields:
Report FieldDescription
`Status`
Summary of the model status, which indicates whether the model was created by construction or obtained by estimation.
`Method`
Estimation command used.
`WindowSize`
Size of the Hamming window.
`DataUsed`
Attributes of the data used for estimation, returned as a structure with the following fields:
FieldDescription
`Name`
Name of the data set.
`Type`
Data type.
`Length`
Number of data samples.
`Ts`
Sample time.
`InterSample`
Input intersample behavior, returned as one of the following values:
• `'zoh'` — Zero-order hold maintains a piecewise-constant input signal between samples.
• `'foh'` — First-order hold maintains a piecewise-linear input signal between samples.
• `'bl'` — Band-limited behavior specifies that the continuous-time input signal has zero power above the Nyquist frequency.
`InputOffset`
Offset removed from time-domain input data during estimation. For nonlinear models, it is `[]`.
`OutputOffset`
Offset removed from time-domain output data during estimation. For nonlinear models, it is `[]`.
For more information on using `Report`, see Estimation Report. | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 1, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.5848735570907593, "perplexity": 4071.4045973055922}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2021-39/segments/1631780055684.76/warc/CC-MAIN-20210917151054-20210917181054-00644.warc.gz"} |
http://www.maplesoft.com/support/help/Maple/view.aspx?path=VectorCalculus/About | VectorCalculus - Maple Programming Help
VectorCalculus
return information on a VectorCalculus object
Parameters
v - Vector or module; any kind of Vector or a VectorSpace module
Description
• The About(v) command returns the type and all relevant data of a VectorCalculus object in a human-readable format.
Examples
> $\mathrm{with}\left(\mathrm{VectorCalculus}\right):$
> $\mathrm{vs}≔\mathrm{VectorSpace}\left({\mathrm{polar}}_{r,\mathrm{θ}},⟨0,1⟩\right):$
> $\mathrm{About}\left(\mathrm{vs}\right)$
$\left[\begin{array}{cc}{\mathrm{Type:}}& {\mathrm{Vector Space}}\\ {\mathrm{Coordinates:}}& {{\mathrm{polar}}}_{{r}{,}{\mathrm{θ}}}\\ {\mathrm{Root Point:}}& \left[{1}{,}\frac{{1}}{{2}}{}{\mathrm{π}}\right]\end{array}\right]$ (1)
> $\mathrm{rv}≔\mathrm{vs}:-\mathrm{Vector}\left(\left[1,1\right]\right):$
> $\mathrm{About}\left(\mathrm{rv}\right)$
$\left[\begin{array}{cc}{\mathrm{Type:}}& {\mathrm{Rooted Vector}}\\ {\mathrm{Components:}}& \left[{1}{,}{1}\right]\\ {\mathrm{Coordinates:}}& {{\mathrm{polar}}}_{{r}{,}{\mathrm{θ}}}\\ {\mathrm{Root Point:}}& \left[{1}{,}\frac{{1}}{{2}}{}{\mathrm{π}}\right]\end{array}\right]$ (2)
> $\mathrm{SetCoordinates}\left({\mathrm{spherical}}_{r,\mathrm{φ},\mathrm{θ}}\right)$
${{\mathrm{spherical}}}_{{r}{,}{\mathrm{φ}}{,}{\mathrm{θ}}}$ (3)
> $\mathrm{fv}≔⟨1,\frac{\mathrm{π}}{2},\mathrm{π}⟩:$
> $\mathrm{About}\left(\mathrm{fv}\right)$
$\left[\begin{array}{cc}{\mathrm{Type:}}& {\mathrm{Free Vector}}\\ {\mathrm{Components:}}& \left[{1}{,}\frac{{1}}{{2}}{}{\mathrm{π}}{,}{\mathrm{π}}\right]\\ {\mathrm{Coordinates:}}& {{\mathrm{spherical}}}_{{r}{,}{\mathrm{φ}}{,}{\mathrm{θ}}}\end{array}\right]$ (4)
> $\mathrm{SetCoordinates}\left({\mathrm{cartesian}}_{x,y}\right)$
${{\mathrm{cartesian}}}_{{x}{,}{y}}$ (5)
> $\mathrm{vf}≔\mathrm{VectorField}\left(⟨y,xy⟩\right):$
> $\mathrm{About}\left(\mathrm{vf}\right)$
$\left[\begin{array}{cc}{\mathrm{Type:}}& {\mathrm{Vector Field}}\\ {\mathrm{Components:}}& \left[{y}{,}{x}{}{y}\right]\\ {\mathrm{Coordinates:}}& {{\mathrm{cartesian}}}_{{x}{,}{y}}\end{array}\right]$ (6)
> $\mathrm{pv}≔\mathrm{PositionVector}\left(\left[3,4\right]\right):$
> $\mathrm{About}\left(\mathrm{pv}\right)$
$\left[\begin{array}{cc}{\mathrm{Type:}}& {\mathrm{Position Vector}}\\ {\mathrm{Components:}}& \left[{3}{,}{4}\right]\\ {\mathrm{Coordinates:}}& {{\mathrm{cartesian}}}_{{x}{,}{y}}\\ {\mathrm{Root Point:}}& \left[{0}{,}{0}\right]\end{array}\right]$ (7)
> $\mathrm{rv2}≔\mathrm{evalVF}\left(\mathrm{vf},⟨3,4⟩\right):$
> $\mathrm{About}\left(\mathrm{rv2}\right)$
$\left[\begin{array}{cc}{\mathrm{Type:}}& {\mathrm{Rooted Vector}}\\ {\mathrm{Components:}}& \left[{4}{,}{12}\right]\\ {\mathrm{Coordinates:}}& {{\mathrm{cartesian}}}_{{x}{,}{y}}\\ {\mathrm{Root Point:}}& \left[{3}{,}{4}\right]\end{array}\right]$ (8) | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 23, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 1, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.9810433387756348, "perplexity": 1363.9955215529003}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 20, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2016-26/segments/1466783393332.57/warc/CC-MAIN-20160624154953-00144-ip-10-164-35-72.ec2.internal.warc.gz"} |
https://www.lmfdb.org/ModularForm/GL2/Q/holomorphic/48/6/a/a/ | # Properties
Label 48.6.a.a Level 48 Weight 6 Character orbit 48.a Self dual yes Analytic conductor 7.698 Analytic rank 0 Dimension 1 CM no Inner twists 1
# Related objects
## Newspace parameters
Level: $$N$$ $$=$$ $$48 = 2^{4} \cdot 3$$ Weight: $$k$$ $$=$$ $$6$$ Character orbit: $$[\chi]$$ $$=$$ 48.a (trivial)
## Newform invariants
Self dual: yes Analytic conductor: $$7.69842335102$$ Analytic rank: $$0$$ Dimension: $$1$$ Coefficient field: $$\mathbb{Q}$$ Coefficient ring: $$\mathbb{Z}$$ Coefficient ring index: $$1$$ Twist minimal: no (minimal twist has level 3) Fricke sign: $$-1$$ Sato-Tate group: $\mathrm{SU}(2)$
## $q$-expansion
$$f(q)$$ $$=$$ $$q - 9q^{3} + 6q^{5} + 40q^{7} + 81q^{9} + O(q^{10})$$ $$q - 9q^{3} + 6q^{5} + 40q^{7} + 81q^{9} + 564q^{11} + 638q^{13} - 54q^{15} + 882q^{17} + 556q^{19} - 360q^{21} + 840q^{23} - 3089q^{25} - 729q^{27} + 4638q^{29} - 4400q^{31} - 5076q^{33} + 240q^{35} - 2410q^{37} - 5742q^{39} - 6870q^{41} - 9644q^{43} + 486q^{45} + 18672q^{47} - 15207q^{49} - 7938q^{51} + 33750q^{53} + 3384q^{55} - 5004q^{57} + 18084q^{59} + 39758q^{61} + 3240q^{63} + 3828q^{65} + 23068q^{67} - 7560q^{69} + 4248q^{71} - 41110q^{73} + 27801q^{75} + 22560q^{77} - 21920q^{79} + 6561q^{81} - 82452q^{83} + 5292q^{85} - 41742q^{87} - 94086q^{89} + 25520q^{91} + 39600q^{93} + 3336q^{95} + 49442q^{97} + 45684q^{99} + O(q^{100})$$
## Embeddings
For each embedding $$\iota_m$$ of the coefficient field, the values $$\iota_m(a_n)$$ are shown below.
For more information on an embedded modular form you can click on its label.
Label $$\iota_m(\nu)$$ $$a_{2}$$ $$a_{3}$$ $$a_{4}$$ $$a_{5}$$ $$a_{6}$$ $$a_{7}$$ $$a_{8}$$ $$a_{9}$$ $$a_{10}$$
1.1
0
0 −9.00000 0 6.00000 0 40.0000 0 81.0000 0
$$n$$: e.g. 2-40 or 990-1000 Significant digits: Format: Complex embeddings Normalized embeddings Satake parameters Satake angles
## Inner twists
This newform does not admit any (nontrivial) inner twists.
## Twists
By twisting character orbit
Char Parity Ord Mult Type Twist Min Dim
1.a even 1 1 trivial 48.6.a.a 1
3.b odd 2 1 144.6.a.f 1
4.b odd 2 1 3.6.a.a 1
8.b even 2 1 192.6.a.l 1
8.d odd 2 1 192.6.a.d 1
12.b even 2 1 9.6.a.a 1
16.e even 4 2 768.6.d.h 2
16.f odd 4 2 768.6.d.k 2
20.d odd 2 1 75.6.a.e 1
20.e even 4 2 75.6.b.b 2
24.f even 2 1 576.6.a.s 1
24.h odd 2 1 576.6.a.t 1
28.d even 2 1 147.6.a.a 1
28.f even 6 2 147.6.e.k 2
28.g odd 6 2 147.6.e.h 2
36.f odd 6 2 81.6.c.c 2
36.h even 6 2 81.6.c.a 2
44.c even 2 1 363.6.a.d 1
52.b odd 2 1 507.6.a.b 1
60.h even 2 1 225.6.a.a 1
60.l odd 4 2 225.6.b.b 2
68.d odd 2 1 867.6.a.a 1
76.d even 2 1 1083.6.a.c 1
84.h odd 2 1 441.6.a.i 1
132.d odd 2 1 1089.6.a.b 1
By twisted newform orbit
Twist Min Dim Char Parity Ord Mult Type
3.6.a.a 1 4.b odd 2 1
9.6.a.a 1 12.b even 2 1
48.6.a.a 1 1.a even 1 1 trivial
75.6.a.e 1 20.d odd 2 1
75.6.b.b 2 20.e even 4 2
81.6.c.a 2 36.h even 6 2
81.6.c.c 2 36.f odd 6 2
144.6.a.f 1 3.b odd 2 1
147.6.a.a 1 28.d even 2 1
147.6.e.h 2 28.g odd 6 2
147.6.e.k 2 28.f even 6 2
192.6.a.d 1 8.d odd 2 1
192.6.a.l 1 8.b even 2 1
225.6.a.a 1 60.h even 2 1
225.6.b.b 2 60.l odd 4 2
363.6.a.d 1 44.c even 2 1
441.6.a.i 1 84.h odd 2 1
507.6.a.b 1 52.b odd 2 1
576.6.a.s 1 24.f even 2 1
576.6.a.t 1 24.h odd 2 1
768.6.d.h 2 16.e even 4 2
768.6.d.k 2 16.f odd 4 2
867.6.a.a 1 68.d odd 2 1
1083.6.a.c 1 76.d even 2 1
1089.6.a.b 1 132.d odd 2 1
## Atkin-Lehner signs
$$p$$ Sign
$$2$$ $$-1$$
$$3$$ $$1$$
## Hecke kernels
This newform subspace can be constructed as the kernel of the linear operator $$T_{5} - 6$$ acting on $$S_{6}^{\mathrm{new}}(\Gamma_0(48))$$.
## Hecke characteristic polynomials
$p$ $F_p(T)$
$2$ 1
$3$ $$1 + 9 T$$
$5$ $$1 - 6 T + 3125 T^{2}$$
$7$ $$1 - 40 T + 16807 T^{2}$$
$11$ $$1 - 564 T + 161051 T^{2}$$
$13$ $$1 - 638 T + 371293 T^{2}$$
$17$ $$1 - 882 T + 1419857 T^{2}$$
$19$ $$1 - 556 T + 2476099 T^{2}$$
$23$ $$1 - 840 T + 6436343 T^{2}$$
$29$ $$1 - 4638 T + 20511149 T^{2}$$
$31$ $$1 + 4400 T + 28629151 T^{2}$$
$37$ $$1 + 2410 T + 69343957 T^{2}$$
$41$ $$1 + 6870 T + 115856201 T^{2}$$
$43$ $$1 + 9644 T + 147008443 T^{2}$$
$47$ $$1 - 18672 T + 229345007 T^{2}$$
$53$ $$1 - 33750 T + 418195493 T^{2}$$
$59$ $$1 - 18084 T + 714924299 T^{2}$$
$61$ $$1 - 39758 T + 844596301 T^{2}$$
$67$ $$1 - 23068 T + 1350125107 T^{2}$$
$71$ $$1 - 4248 T + 1804229351 T^{2}$$
$73$ $$1 + 41110 T + 2073071593 T^{2}$$
$79$ $$1 + 21920 T + 3077056399 T^{2}$$
$83$ $$1 + 82452 T + 3939040643 T^{2}$$
$89$ $$1 + 94086 T + 5584059449 T^{2}$$
$97$ $$1 - 49442 T + 8587340257 T^{2}$$ | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 1, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.904830813407898, "perplexity": 21998.527267875204}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2020-34/segments/1596439738727.76/warc/CC-MAIN-20200811025355-20200811055355-00595.warc.gz"} |
https://docs.welsim.com/welsim/theory/contact/ | # Structures with contact¶
As contact occurs among multiple bodies, the contact force $$\mathbf{t}_{c}$$ is transmitted via the contact surface. The principle equation of the virtual work can be rewritten as follows
\begin{align} \label{eq:ch5_contact_gov1} \intop_{^{t'}V}\thinspace^{t'}\sigma\colon\delta^{t'}\mathbf{A}_{(L)}d^{t'}v=\intop_{^{t'}S_{t}}\thinspace^{t'}\mathbf{t}\cdot\delta\mathbf{u}d^{t'}s+\intop_{V}\thinspace^{t'}\mathbf{b}\cdot\delta\mathbf{u}d^{t'}v+\intop_{^{t'}S\text{c}}\thinspace^{t'}\mathbf{t}_{c}[\delta\mathbf{u}^{(1)}-\delta\mathbf{u}^{(2)}] \end{align}
where notation $$s_{c}$$ represents the contact area, $$\mathbf{u}^{(1)}$$ and $$\mathbf{u}^{(2)}$$ denotes the displacement of the contact object 1 and 2, respectively.
In the contact analysis, the surfaces involve contact are paired. One of these surfaces is called the master surface, and another type of surface is target surface. We also assume
• The target nodes do not penetrate the master surface
• When contact occurs, the target nodes become the contact position, the master surface and the target surface mutually transmit the contact force and the frictional force through the points of contact.
The governing equations with contact term can be reduced to the finite element formation
$\intop_{^{t'}S_{c}}\thinspace^{t'}\mathbf{t}_{c}[\delta\mathbf{u}^{(1)}-\delta\mathbf{u}^{(2)}]\approx\delta\mathbf{UK}_{C}\triangle\mathbf{U}+\delta\mathbf{UF}_{C}$
where $$\mathbf{K}_{c}$$ and $$\mathbf{F}_{c}$$ are contact rigid matrix, and the contact forces, respectively.
Remember that we introduced total Lagrange and update Lagrange methods, those formulation can be extended with the consideration of contact factors. The total Lagrange and updated Lagrange formulation with contact terms are given below
$\delta\mathbf{U}^{T}(_{0}^{t}\mathbf{K}_{L}+_{0}^{t}\mathbf{K}_{NL}+\mathbf{K}_{c})\triangle\mathbf{U}=\delta\mathbf{U}^{T}\thinspace_{0}^{t'}\mathbf{F}-\delta\mathbf{U}^{T}\thinspace_{0}^{t}\mathbf{Q}+\delta\mathbf{U}^{T}\mathbf{F}_{c}$
$\delta\mathbf{U}^{T}(_{t}^{t}\mathbf{K}_{L}+_{t}^{t}\mathbf{K}_{NL}+\mathbf{K}_{c})\triangle\mathbf{U}=\delta\mathbf{U}^{T}\thinspace_{t}^{t'}\mathbf{F}-\delta\mathbf{U}^{T}\thinspace_{t}^{t}\mathbf{Q}+\delta\mathbf{U}^{T}\mathbf{F}_{c}$ | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 1, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 1, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.18300676345825195, "perplexity": 862.7140840132834}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2022-33/segments/1659882570651.49/warc/CC-MAIN-20220807150925-20220807180925-00547.warc.gz"} |
https://physics.stackexchange.com/questions/456150/how-can-an-object-with-zero-potential-and-kinetic-energy-ever-move | # How can an object with zero potential and kinetic energy ever move?
I am not sure how to ask this question but I am learning about potential energy in my high school physics class. From the definition of potential energy, (energy stored in an object with the potential to convert into other type of energy), I don't understand how an object (let's say a ball) on the ground, which has zero kinetic energy and zero potential energy, can fall off a cliff and gain kinetic energy when it had no potential energy. How can it now be gaining energy? Also, another question that was already discussed in SE (but I didn't find my answer there), is why do we talk about the potential energy of a system (ball+Earth) but kinetic energy of an object (ball)?
Thanks.
Where we define the potential energy to be $$0$$ in classical mechanics is arbitrary. All that matters is the change in potential energy. Since you are just learning this stuff I will assume you are in an algebra based physics class, so I will avoid using calculus here.
Potential energies are nice because they tell us how much work is done by a conservative force. More specifically, the work done by a conservative force is given by $$W_{cons}=-\Delta U$$ where $$U$$ is the potential energy associated with that conservative force. This is useful because we also know that the net work done on an object determines its change in kinetic energy $$W_{net}=\Delta K$$
So, if we consider your case where we just have one conservative force acting on the object, we can conclude that $$\Delta K=-\Delta U$$
And so we see here that the only thing that determines how the motion of our object changes is just the change in potential energy. If we define the zero-point to be at the top of the cliff, then as the object falls its kinetic energy will grow and its potential energy will decrease and be negative when it hits the bottom of the cliff. If we define the zero-point to be at the bottom of the cliff then as the object falls its kinetic energy will grow and its potential energy will decrease to $$0$$ when it hits the bottom of the cliff. In either case the same thing happens because we have the same change in potential energy.
Also another question that was already discussed in SE (but i didn't find my answer there) is why do we talk about the potential energy of a system (ball+Earth) but kinetic energy of an object (ball)?
Typically in introductory physics classes we just consider the ball being in a uniform gravitational field and we don't even consider the Earth. However if you want to include the Earth in your system then when the ball falls the Earth will actually move slightly upwards to meet the ball. It will still be the case though that the work done by gravity on each object is related to the change in the potential energy of each object, which results in a change of kinetic energy.
• "All that matters is the change in potential energy". That is true when calculating kinetic energy gained, but two balls at equal heights in the air, one above high ground an one above a cliff still have the same potential energy. Does a ball on top of a mountain have potential energy? Yes because the potential energy it accumulated while being lifted up there, even thou it is standing still. Jan 23, 2019 at 17:51
• @AlexDoe You can say that the potential energy increased as you lifted the ball to the top of the mountain, but if you set $h=0$ at the top then you can say the ball's potential energy is $0$. That is why it is better to say "the ball's potential energy increased" Jan 23, 2019 at 18:40
• I see your point. I think the opinion differences are in terminology. The way I was looking at it is like if I go to the mall and I set a limit as to how much I want to spend there (arbitrary). That doesn't mean that that's all the money (potential energy) that I have. Thanks for the input thou. Seems like I am a minority/alone on this side of the isle thou :) Jan 23, 2019 at 19:10
• @AlexDoe In your analogy it doesn't matter where you set your spending limit. You could spend more or less money than your limit and have "positive or negative" cash relative to that limit, but either way the new shirt you buy will change the amount of cash you have in your account by the same amount no matter what you decide your spending limit is. Jan 23, 2019 at 19:14
• @AlexDoe: I agree with you; I think it would be better to say "All that matters is differences in potential energy" (rather than specifically change). The "zero" is arbitrary, but you need to fix it once and stick with it for a whole calculation -- you can't just keep resetting your arbitrary zero and expect everything to work out. Jan 23, 2019 at 20:04
The energy of an object consists of its internal energy (kinetic and potential energy possessed internally to an object at the atomic or molecular level) and external kinetic and potential energy. Its external kinetic and potential energy is always with respect to some external frame of reference.
The ball on the surface of the earth may have zero potential energy with respect to the surface of the earth, but has gravitational potential energy with respect to the center of the earth. It doesn’t move because the force of gravity downward on the ball is equal and opposite to the force exerted upward on it by the ground. But imagine if there was a trench that went from one side of the earth to the other. If the ball were positioned over the hole and allowed to fall, it would accelerate toward the center of the earth losing potential energy and gaining kinetic energy, the latter being a maximum at the center where its potential energy is zero. Then it would decelerate as it goes past the center as it gains potential energy and loses kinetic energy, ultimately stopping at the other side (ignoring air resistance).
Even the kinetic energy of the object is relative to the frame of reference where the velocity is measured. If you are in a car moving at velocity $$v$$ with respect to the road, it has zero kinetic energy in your frame of reference. It is not “moving” in your frame of reference, but is moving in the frame of reference of a person standing on the road. To that person the car has kinetic energy. The person standing on the road is “moving” with respect to your frame of reference in the car, so that person has kinetic energy with respect to you in the car. The person standing on the road has kinetic energy with respect to a frame of reference other than the earth (since the earth is rotating). And so on…
Bottom line, everything can be considered to have kinetic energy (be moving) with respect to some frame of reference and have potential energy (due to its position) with respect to some frame of reference.
Hope this help.
• I like how you mention the arbitrariness of the "zero-point" of kinetic energy. I knew this was the case, but never realized how they are kind of the same idea. In a sense, just like how we define where $h=0$ for the zero-point of potential energy, we can also define what constitutes as $v=0$ for a sort of "zero-point" of kinetic energy. Jan 23, 2019 at 16:56
• Thanks. I like the way you call it "zero point" kinetic and potential energy. Jan 23, 2019 at 17:02
• Yeah it is probably not the most accurate terminology considering the use of "zero-point energy" in QM, but since we are in the classical realm for this question I think I will keep it haha Jan 23, 2019 at 17:03
• @Ed999 Bob never said anything contradicting what you just explained Jan 23, 2019 at 18:44
• @Ed999 I thought that's what I said. Jan 23, 2019 at 19:18
I am not sure how to ask this question but I am learning about potential energy (high school physics) and from the deffinition of a potential energy (energy stored in an object with the potential to convert into other type of energy)
this definition of potential energy, sounds more like the energy itself. More below
i don't understand how for eg. when we have an object (let's say a ball) on the ground, it has zero kinetic energy and also zero potential energy and now let's say the ball starts falling of a cliff so it will be gaining kinetic energy but when it had no potential energy, how can it be now gaining energy?
indeed, in the planet+object system, the true 0 potential, would be better put at the center of gravity the earth if the reference frame is attached to the earth, if the reference frame is attached to the object, then it should be on the center of gravity of the object, and if the reference frame is neither, the 0 potential should be at the center of gravity of the object+earth system.
Also another question that was already discussed in SE (but i didn't find my answer there) is why do we talk about the potential energy of a system (ball+Earth) but kinetic energy of an object (ball)?
Because you need to define what type of potential energy we are talking about, in this case it's gravity (could be electrical for example)
We now see that potential energy is relative to a type of force (gravity), reference frame, and the final nail in the coffin of your definition of potential energy, is that it's not "stored in the object" . Potential energies depend on the spacial position of the object in the force field.
I hope all these elements will help you understand potential energy. Meanwhile your teacher probably gave you a simplified version of this that is enough to solve the problems you are supposed to solve for now. The main idea the teacher probably wants to convey is that energy is conserved, and that like voltage, we are more interested in differences in potential than absolute potentials.
A moving object, due to its inertia, has an energy (that could do damage in case it impacts something :) We call that energy "Kinetic"
A system (like the earth and ball) can potentially (if allowed) cause one or both objects to move because of the gravity (in this case).
If the force of gravity is perpendicular to the surface where the ball meets the earth, that hard surface prevents the ball from going anywhere so we are saying that the ball can potentially gain no speed thus it has "no potential energy".
This is where the confusion starts, because in fact that ball had potential energy (if only allowed to move). The only place where the ball could really have zero potential energy would be at the lowest point on the surface of the earh (or that of the surface of the ocean floor depending on the density of the ball) If we move the ball to the side making available a cliff where the ball could potentially roll down on, we realise that the ball (or the system) did have potential energy, we just said it didn't, for practical reasons.
• Your answer seems to put a lot of importance on where we actually define potential energy to be $0$, when in fact the $0$ point is arbitrary. Jan 23, 2019 at 16:28
• But then I don't get what the potential energy represents or why do we even need it when we can choose the point where potential energy is 0, then the value of potential energy will be different for the same object (position) everytime we choose a different 0 point. Like for eg if you compared two velocities one with the magnitude 0m/s and one 10m/s you know the other object is faster, but with PE the same object in one position can have different magnitude/value depending on the zero point. So the value doen't represent anything in my opinion, or what does it represent? Jan 23, 2019 at 16:32
• @LaurenSin What really matters is changes in potential energy. The absolute value of it does not matter. Also when comparing two objects you still use the same zero-point for each object, so it is still relevant to say which object has more potential energy that could be converted to kinetic energy should both objects end up with the same potential energy while they move. But the same thing will happen to an object going from potential energies of $5\ \rm J$ to $3\ \rm J$ as one going from $2\ \rm J$ to $0\ \rm J$ Jan 23, 2019 at 16:36
• You need to avoid these kind of abstract concepts, because they will lead you nowhere. Unless we have a machine which can convert gravitational energy into some other kind of energy, there is no practical value in calculating gravitational potential energy. Actually, we do have such a machine, it's called a waterwheel. Hydroelectric dams use this principle too. You might find that in these more concrete examples, the frame of reference defines itself. The water has a defined volume and mass,and a defined distance to fall at 1G acceleration, to convert its potential energy into kinetic energy. Jan 23, 2019 at 18:23
When An object is on a cliff at rest then relative to ground ,it will have 0 kinetic energy.we can take the surface of the cliff at 0 potential. When it is on surface of cliff,Two forces are working on it, The gravitational force of earth and the normal force of surface.Net force is zero, So it is in equilibrium.As net force is zero,so change in it's kinetic energy or its potential energy is also zero ($$F=-dU/dx$$).
When it is falling from the cliff ,we removed the normal force ,so net force is acting that is gravitational force. This will change its potential (kinetic)energy. We assumed the cliff at 0 potential energy ,so the force will decrease the potential energy in negative as wolframe johny said.
The “energy” is just an abstract accounting tool that we use to describe the results of those interactions in terms of the work being done.
We talk about the potential energy of system ,because we need force that will cause change in potential energy,but kinetic energy is just because of the relative motion of the object
If the ball was on top of a cliff, then it already had gravitational potential energy. This comes from the fact that if the ball fell off the cliff, if would gain kinetic energy (while losing the potential energy it had from being on top of the cliff).
Gravitational potential energy is usually discussed with respect to a system because there needs to be other mass(es) exerting gravity on an object to give it said potential energy. However, there are other types of potential energy internal to an object (e.g., chemical potential energy), that has no reliance on an external system.
The main thing to remember is that potential energy is how much kinetic energy an object could potentially exert. An object being on top of a cliff has potential energy since it has the potential to drop off the cliff and gain kinetic energy.
• I think there's something missing here about the arbitrariness of the zero point of kinetic/potential energy. Whatever numerical value we choose to assign to the potential energy of a ball at the top of a cliff is rather meaningless. Suppose the ball falls to the bottom of the cliff, gaining a certain amount of KE before it lands. Now it turns out the ball landed on a trap door and falls through, gaining even more KE, even though in the frame of reference we started in, the ball didn't ever have that much PE. All that matters is the change in KE and PE, but not the actual numerical values. Jan 23, 2019 at 20:39 | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 8, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.7972953915596008, "perplexity": 210.2492182090859}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 20, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2022-21/segments/1652662541747.38/warc/CC-MAIN-20220521205757-20220521235757-00712.warc.gz"} |
http://tex.stackexchange.com/questions/48842/shifting-the-subcaption-in-subfigure | # Shifting the subcaption in subfigure [closed]
I have a subfigure in which I want to shift one of the figures to the left, but when I shift it the caption is in its place. what should I do?
Here is what I have in latex:
\begin{figure*}[ht]
\hspace{-4cm}
\subfigure[1]{
\includegraphics[scale=1]{1.eps}
\label{fig:1}
}
\\
\subfigure[2]{
\hspace{-4cm}
\includegraphics[scale=1]{2.eps}
\label{fig:2}
}
\label{fig:fig}
\caption[fig:fig]{caption}
\end{figure*}
The problem is with figure 2
-
## closed as too localized by lockstep, percusse, egreg, Marco Daniel, SeamusMay 10 '12 at 10:47
This question is unlikely to help any future visitors; it is only relevant to a small geographic area, a specific moment in time, or an extraordinarily narrow situation that is not generally applicable to the worldwide audience of the internet. For help making this question more broadly applicable, visit the help center.If this question can be reworded to fit the rules in the help center, please edit the question.
It's quite unclear why you should use \hskip{-4cm} to begin with. – egreg Mar 21 '12 at 16:03
Your problem is better understood if you provide a complete MWE (instead of snippets). You are using \begin{figure*}. Are you using 2 column format? Do you want figures to come one below the other? Are you using subfigure package? If so, kindly consider using subfig instead as the former is obsolete. Bottom line: MWE please. – Harish Kumar Mar 21 '12 at 17:07 | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 1, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.7666663527488708, "perplexity": 1698.6571089122367}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 20, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2014-52/segments/1418802769373.55/warc/CC-MAIN-20141217075249-00114-ip-10-231-17-201.ec2.internal.warc.gz"} |
https://www.zonakamu.com/2016/06/lirik-lagu-why-dont-we-go-there-one.html | I know you want, know you wanna take it slow
But think about all the places we could go
If you give in tonight
Just let me set you free
We'll touch the other side,
Just give me the key
'Cause we got all night
And we're going nowhere
Why don't you stay?
Why don't we go there?
Let's take a ride
Out in the cold air
I know the way.
Why don't you go there with me?
Say the word, say the word but don't say "No"
Skydive, you and I, with just these clothes
The secret's safe with me
There's no right time or place
'Cause anyone could see
We'll do it anyway
'Cause we got all night
We're going nowhere
Why don't you stay?
Why don't we go there?
Let's take a ride
Out in the cold air
I know the way.
Why don't you go there with me?
Hey, I don't want you to be the one that got away
I wanna get addicted to you, yeah
You're rushing through my mind,
I wanna feel the high
I wanna be addicted, don't say "No"
Just let go
'Cause we got all night
And we're going nowhere
Why don't you stay?
Why don't we go there?
Let's take a ride (let's take a ride)
Out in the cold air
I know the way (I know the way).
Why don't you go there with me?
With me, with me
Why don't you go there with me? | {"extraction_info": {"found_math": false, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.8007717132568359, "perplexity": 8243.655441533178}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2023-14/segments/1679296949035.66/warc/CC-MAIN-20230329213541-20230330003541-00465.warc.gz"} |
https://arbital.greaterwrong.com/p/googol?l=42m | # A googol
$$10^{100},$$ i.e., 10000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000.
The search engine Google is named after the number googol. (The difference for the spelling, as the apocryphal story goes, comes from the fact that one of the early Google investors misspelled the name on a check.)
Parents: | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 1, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.25535959005355835, "perplexity": 3624.952776803592}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2021-31/segments/1627046150264.90/warc/CC-MAIN-20210724094631-20210724124631-00573.warc.gz"} |
http://mathhelpforum.com/pre-calculus/196864-limits-sum.html | Math Help - limits sum
1. limits sum
i have a problem in the sum below as attachment
Attached Thumbnails
2. Re: limits sum
Try to approximate the product using Riemann sums. | {"extraction_info": {"found_math": false, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.9998120665550232, "perplexity": 6412.038159439667}, "config": {"markdown_headings": false, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2014-10/segments/1394678693350/warc/CC-MAIN-20140313024453-00060-ip-10-183-142-35.ec2.internal.warc.gz"} |
https://www.physicsforums.com/threads/quick-question.273334/ | # Quick Question
1. Nov 19, 2008
### Ninjarzz
1. The problem statement, all variables and given/known data
So we did a lab this week in my physics class.
We had a car on a horizontal table, that was attached to a string with weights (The weights were over the edge of the table.) We then calculated the experimental acceleration and the calculated acceleration. These numbers were different.
My teacher asked us "What was causing the difference between the calculated acceleration and experimental acceleration..."
He also mentioned something to do with Newton's laws.
Do you know the answer/Can help me out?
HUMAN ERROR IS NOT THE ANSWER...And the the time was taken by a electronic device.
2. Relevant equations
g = 9.8 m/s
3. The attempt at a solution
I really dont know how to start! whats causing the difference!
Last edited: Nov 19, 2008
2. Nov 19, 2008
### unscientific
Friction, human reaction time. F = d(mv)/dt
Since friction affects net force, reaction affects time, one wouldnt expect to get the exact answer..
3. Nov 19, 2008
### Ninjarzz
I'm not really sure what you mean by human reaction time?
Elaborate? like ... the time that i calculated forit to go? because it was takeen by a stop watch
4. Nov 19, 2008
### unscientific
ok, human has a reaction time of about 0.19s. Which means you could have pressed the time too late, which means the time u measure is more than the the theoretically calculated time.
Similar Discussions: Quick Question | {"extraction_info": {"found_math": false, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.8342982530593872, "perplexity": 2321.0513277009136}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2017-22/segments/1495463607593.1/warc/CC-MAIN-20170523083809-20170523103809-00308.warc.gz"} |
https://www.physicsforums.com/threads/finding-limitations-for-matrix.799488/ | # Finding limitations for matrix
1. Feb 23, 2015
### nuuskur
1. The problem statement, all variables and given/known data
Let $A\in Mat_{3,4}(K)$. Find all matrices X such that $\forall X| A\cdot X = A'$, where A' is the same as A with 2nd and 4th column swapped.
2. Relevant equations
3. The attempt at a solution
First we determine the size of matrix X. By definition the first factor must have as many columns as the second has rows and the end product is $A_{m,n}\cdot B_{n,p} = C_{m,p}$. X must be 4 x 4. Let $a'_{i,j}\in A', a_{i,j}\in A$
Haven't been able to (in my opinion) come up with anything sensible. Essentially, I have noticed that if we denote rows of A and columns of X as vectors, such that $a_1 = (a_{1,1},a_{1,2},a_{1,3},a_{1,4})$(by row up to a3) and $x_1 = (x_{1,1},x_{2,1},x_{3,1},x_{4,1})$(by column up to x4)
Then the dot products equal to the corresponding element of A except when we multiply by either x2 or x4. Problem is, where do I find the conditions for matrix X?
I can also write out the dot products individually, but then I have 3 equations and 4 variables..
I have concluded that:
$$\begin{cases} a'_{i,j} = a_{i,j}= \sum_{k=1}^4 a_{i,k}\cdot x_{k,j},& j\in\{1,3\}\\ a'_{i,2} = \sum_{k=1}^4 a_{i,k}\cdot x_{k, 2} = a_{i,4}\\ a'_{i,4} = \sum_{k=1}^4 a_{i,k}\cdot x_{k, 4} = a_{i,2} \end{cases}$$
THIS LOOKS UGLY! I can't think of any other way to show conditions for all x in X :s
This definitely is not acceptable, suggestions?
(I want to avoid writing out individual x - what if the dimensions of the matrix are countible? Would take a long time to write them out xD)
2. Feb 23, 2015
### Svein
If X were the identity matrix it would look like this: $\begin{matrix} 1 & 0 & 0 & 0 \\ 0 & 1 & 0 & 0\\ 0 & 0 & 1 & 0 \\ 0 & 0 & 0 & 1 \\ \end{matrix}$. The second row controls the second column in the product, and the fourth row controls the fourth column.
3. Feb 23, 2015
### Ray Vickson
Google 'matrix column operations'; for example, see
http://stattrek.com/matrix-algebra/elementary-operations.aspx
or
https://unapologetic.wordpress.com/2009/08/27/elementary-row-and-column-operations/
These show explicitly how to find the matrix X. (They leave unanswered the question of whether X is unique---they just show how to find one possible X.)
4. Feb 24, 2015
### nuuskur
Okay, if I approach this deductively, then
$a'_{11} = a_{11}\cdot x_{11} + a_{12}\cdot x_{21} + a_{13}\cdot x_{31} + a_{14}\cdot x_{41} = a_{11}$ if x11 = 1, then the other three summands would sum to 0 and the resulting matrix is very similar to the identity matrix, BUT
x11 does not have to be 1 in which case everything breaks.
Intuitively I am quite sure that the X is the identity matrix with 2, 4 column swapped - but this is all deduction based math. I am not satisfied.
5. Feb 24, 2015
### Ray Vickson
What is unsatisfactory about it? What is wrong with building on past knowledge developed by others? | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 1, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.8979381322860718, "perplexity": 587.3430091899867}, "config": {"markdown_headings": true, "markdown_code": false, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2017-34/segments/1502886104560.59/warc/CC-MAIN-20170818024629-20170818044629-00417.warc.gz"} |
https://www.beckmann.pro/pubtype/conference/ | ### Publication Types:
#### Total Search Problems in Bounded Arithmetic and Improved Witnessing
conference
Arnold Beckmann and Jean-Jose Razafindrakoto
24th International Workshop on Logic, Language, Information, and Computation (WoLLiC), 2017. Pages: 31 - 47
Publication year: 2017
We define a new class of total search problems as a subclass of Megiddo and Papadimitriou’s class of total $\NP$ search problems, in which solutions are verifiable in $\AC^0$. We denote this class $\forall\exists\AC^0$. We show that all total $\NP$ search problems are equivalent wrt. $\AC^0$-many-one reductions to search problems in $\forall\exists\AC^0$. Furthermore, we show that $\forall\exists\AC^0$ contains well-known problems such as the Stable Marriage and the Maximal Independent Set problems. We introduce the class of Inflationary Iteration problems in $\forall\exists\AC^0$ and show that it characterizes the provably total $\NP$ search problems of the bounded arithmetic theory corresponding to polynomial-time. Cook and Nguyen introduced a generic way of defining a bounded arithmetic theory $\VC$ for complexity classes $\C$ which can be obtained using a complete problem. For such $C$ we will define a new class $\KPT[C]$ of $\forall\exists\AC^0$ search problems based on Student-Teacher games in which the student has computing power limited to $\AC^0$. We prove that $\KPT[C]$ characterizes the provably total $\NP$ search problems of the bounded arithmetic theory corresponding to $\C$. All our characterizations are obtained via “new-style” witnessing theorems, where reductions are provable in a theory corresponding to $\AC^0$.
#### Hyper Natural Deduction
conference
Arnold Beckmann and Norbert Preining
Symposium on Logic in Computer Science (LICS), 2015, 30th Annual ACM/IEEE. Pages: 547 - 558
Publication year: 2015
We introduce a Hyper Natural Deduction system as an extension of Gentzen’s Natural Deduction system. A Hyper Natural Deduction consists of a finite set of derivations which may use, beside typical Natural Deduction rules, additional rules providing means for communication between derivations. We show that our Hyper Natural Deduction system is sound and complete for infinite-valued propositional Gödel Logic, by giving translations to and from Avron’s Hyper sequent Calculus. We also provide conversions for normalisation and prove the existence of normal forms for our Hyper Natural Deduction system.
#### Parity Games and Propositional Proofs
conference
Arnold Beckmann, Pavel Pudlák and Neil Thapen
38th International Symposium on Mathematical Foundations of Computer Science, MFCS 2013, Klosterneuburg, Austria, August 26-30, 2013. LNCS 8087. Pages: 111-122
Publication year: 2013
A propositional proof system is weakly automatizable if there is a polynomial time algorithm which separates satisfiable formulas from formulas which have a short refutation in the system, with respect to a given length bound. We show that if the resolution proof system is weakly automatizable, then parity games can be decided in polynomial time. We also define a combinatorial game and prove that resolution is weakly automatizable if and only if one can separate, by a set decidable in polynomial time, the games in which the first player has a positional winning strategy from the games in which the second player has a positional winning strategy.
#### Using Domain Specific Languages to Support Verification in the Railway Domain
conference
Phillip James, Arnold Beckmann, Markus Roggenbach
Hardware and Software: Verification and Testing. 8th International Haifa Verification Conference, HVC 2012 Haifa, Israel, November 6-8, 2012. Pages: 274 -275
Publication year: 2012
We explore the support of automatic verification via careful design of a domain specific language (DSL) in the context of algebraic specification. Formally a DSL is a loose specification the logical closure of which we regard as implicitly encoded “domain knowledge”. We systematically exploit this “domain knowledge” for automatic verification. We illustrate these ideas within the Railway Domain using the algebraic specification language Casl and an existing DSL, designed by Bjøerner, for modelling railways. Empirical evidence to the benefit of our approach is given in the form of the successful automatic verification of four railway track plans of real world complexity.
#### A Characterisation of Definable NP Search Problems in Peano Arithmetic
conference
Arnold Beckmann
Logic, Language, Information and Computation. 16th International Workshop, WoLLIC 2009, Tokyo, Japan, June 21-24, 2009. Pages: 1 - 12
Publication year: 2009
The complexity class of $\prec$-bounded local search problems with goals is introduced for well-orderings $\prec$, and is used to give a characterisation of definable NP search problems in Peano Arithmetic.
#### On the computational complexity of cut-reduction
conference
Klaus T Aehlig and Arnold Beckmann
Logic in Computer Science, 2008. LICS '08. 23rd Annual IEEE Symposium on 24-27 June 2008. Pages: 284 - 293
Publication year: 2008
Using appropriate notation systems for proofs, cut-reduction can often be rendered feasible on these notations, and explicit bounds can be given. Developing a suitable notation system for Bounded Arithmetic, and applying these bounds, all the known results on definable functions of certain such theories can be reobtained in a uniform way.
#### On the complexity of parity games
conference
Arnold Beckmann and Faron G Moller
Visions of Computer Science — BCS International Academic Conference Imperial College, London, UK - 22 - 24 September 2008. Pages: 237 - 247
Publication year: 2008
Parity games underlie the model checking problem for the modal μ-calculus, the complexity of which remains unresolved after more than two decades of intensive research. The community is split into those who believe this problem – which is known to be both in NP and coNP – has a polynomial-time solution (without the assumption that P=NP) and those who believe that it does not. (A third, pessimistic, faction believes that the answer to this question will remain unknown in their lifetime.)
In this paper we explore the possibility of employing Bounded Arithmetic to resolve this question, motivated by the fact that problems which are both NP and coNP, and where the equivalence between their NP and coNP description can be formulated and proved within a certain fragment of Bounded Arithmetic, necessarily admit a polynomial-time solution. While the problem remains unresolved by this paper, we do proposed another approach, and at the very least provide a modest refinement to the complexity of parity games (and in turn the μ-calculus model checking problem): that they lie in the class of Polynomial Local Search problems. This result is based on a new proof of memoryless determinacy which can be formalised in Bounded Arithmetic.
The approach we propose may offer a route to a polynomial-time solution. Alternatively, there may be scope in devising a reduction between the problem and some other problem which is hard with respect to PLS, thus making the discovery of a polynomial-time solution unlikely according to current wisdom.
#### Propositional Logic for Circuit Classes
conference
Klaus T Aehlig and Arnold Beckmann
21st International Workshop, CSL 2007, 16th Annual Conference of the EACSL, Lausanne, Switzerland, September 11-15, 2007. Pages: 512 - 526
Publication year: 2007
By introducing a parallel extension rule that is aware of independence of the introduced extension variables, a calculus for quantified propositional logic is obtained where heights of derivations correspond to heights of appropriate circuits. Adding an uninterpreted predicate on bit-strings (analog to an oracle in relativised complexity classes) this statement can be made precise in the sense that the height of the most shallow proof that a circuit can be evaluated is, up to an additive constant, the height of that circuit.
The main tool for showing lower bounds on proof heights is a variant of an iteration principle studied by Takeuti. This reformulation might be of independent interest, as it allows for polynomial size formulae in the relativised language that require proofs of exponential height.
#### Resolution Refutations and Propositional Proofs with Height-Restrictions
conference
Arnold Beckmann
In: Bradfield J. (eds) Computer Science Logic. CSL 2002. Lecture Notes in Computer Science, vol 2471. Springer, Berlin, Heidelberg, Pages 599 - 612.
Publication year: 2002
Height restricted resolution (proofs or refutations) is a natural restriction of resolution where the height of the corresponding proof tree is bounded. Height restricted resolution does not distinguish between tree- and sequence-like proofs. We show that polylogarithmic-height resolution is strongly connected to the bounded arithmetic theory S^1_2(\alpha) . We separate polylogarithmic-height resolution from quasi-polynomial size tree-like resolution. Inspired by this we will study infinitely many sub-linear-height restrictions given by functions n → 2_i((log^(i+1) n)^O(1)) for i ≥ 0 . We show that the resulting resolution systems are connected to certain bounded arithmetic theories, and that they form a strict hierarchy of resolution proof systems. To this end we will develop some proof theory for height restricted proofs.
#### A note on universal measures for weak implicit computational complexity
conference
Arnold Beckmann
9th International Conference, LPAR 2002, Tbilisi, Georgia, October 14-18, 2002, Pages: 53 - 67
Publication year: 2002
This note is a case study for finding universal measures for weak implicit complexity. We will instanciate “universal measures” by “dynamic ordinals”, and “weak implicit complexity” by “bounded arithmetic”. Concretely, we will describe the connection between dynamic ordinals and witness oracle Turing machines for bounded arithmetic theories. | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.7496330142021179, "perplexity": 1303.6344629072105}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2020-40/segments/1600402093104.90/warc/CC-MAIN-20200929221433-20200930011433-00497.warc.gz"} |
https://www.gradesaver.com/textbooks/math/other-math/thinking-mathematically-6th-edition/chapter-11-counting-methods-and-probability-theory-11-1-the-fundamental-counting-principle-exercise-set-11-1-page-693/10 | Thinking Mathematically (6th Edition)
The number of ways in which a series of successive things can occur is found by multiplying the number of ways in which each thing can occur. ---------- 1. The number of bedrooms can be chosen in 3 ways. 2. The number of bathrooms can be chosen in 2 ways. 3. The floor can be chosen in 2 ways. 4. The view can be chosen in 3 ways. Applying the Principle, the total number of apartment options is 3$\times$2$\times$2$\times$3$=36$ Sample apartment options: One bedroom - one bathroom - first floor - lake view. One bedroom - one bathroom - first floor - golf course view. | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.793459415435791, "perplexity": 741.8201016426832}, "config": {"markdown_headings": false, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2018-17/segments/1524125948617.86/warc/CC-MAIN-20180426222608-20180427002608-00062.warc.gz"} |
https://docs.wavesenterprise.com/en/latest/get-started/private-network/additional/additional-tls.html | Installation and usage of the platform
# Precise platform configuration: TLS¶
To work with smart contracts, the node uses two connection types, for each of which you can configure TLS: docker-TLS and API connection
You can configure TLS for gRPC and REST API for each node using the gRPC and REST API operation parameters in the api section of the node configuration file. To configure TLS, use the TLS parameter in the rest block and in the grpc block.
To work with TLS for API:
1. obtain TLS artefacts:
• obtain keystore file named we.jks;
• issue we.cert client certificate;
• import the client certificate into the trusted certificates storage.
An example of the preparation of these artifacts is given in the following section:
1. specify the relative path to the we.jks keystore file in the tls section of the node configuration file.
## tls section of the node configuration file¶
The tls section contains the following parameters:
tls {
type = EMBEDDED
keystore-path = ${node.directory}"/we_tls.jks" keystore-password =${TLS_KEYSTORE_PASSWORD}
private-key-password = ${TLS_PRIVATE_KEY_PASSWORD} } • type – TLS mode status. Possible options: • DISABLED – disabled, in this case other options should be excluded or commented out and • EMBEDDED – enabled, the certificate is signed by a node provider and packed within a JKS file (keystore); the certificate directory and keystore access parameters should be stated by a user in the fields below. • keystore-path – keystore relative path within the node directory: ${node.directory}"/we_tls.jks".
• keystore-password – password for the node keystore. Specify the password you set earlier with the storepass flag for the keytool utility.
• private-key-password – password for the private key. Specify the password you set earlier with the keypass flag for the keytool utility. | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 0, "mathjax_asciimath": 1, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.39091363549232483, "perplexity": 11365.977274136769}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2022-40/segments/1664030334802.16/warc/CC-MAIN-20220926051040-20220926081040-00530.warc.gz"} |
https://es.mathworks.com/help/phased/ug/examine-the-response-of-a-focused-array.html | Main Content
# Examine the Response of a Focused Phased Array
### Introduction
This example introduces the concept of a focused beam, and shows how to use `phased.FocusedSteeringVector` to generate the required element weights for a phased array. It also shows how to use `phased.SphericalWavefrontArrayResponse` to compute the array response of an array at a given angle and range. First you will look at the response when a single beam is formed and examine characteristics of the focal region, then emulate a collection strategy commonly used in ultrasound imaging to see how a focused beam appears in an image.
### Focused Beamforming
#### Spherical Wavefront Delay-and-Sum
Beamforming under the typical far-field assumption enables modeling the signal wavefront as a plane which is propagating along its normal direction. When the signal is incident on an array, the wavefront intersects individual elements with a relative time delay that is proportional to the distance of the element along the wave's propagation direction. Under this model, a delay (or phase shift, in the narrowband case) can be applied to each element such that the outputs across elements (whether on transmit or receive) have constructive phase when coherently summed.
Without the far-field assumption, the wavefront emanating from a point source is modeled as a spherical surface centered at that soure. This wavefront intersects the elements of the phased array with relative time delay dictated by the hyperbolic range across colinear elements. While this model would simply add unneccessary computation cost to the generation of a far-field pattern, the spherical wavefront model is necessary to understand near-field beamforming and focusing.
The function `helperPlotULAWavefronts` is provided to demonstrate the difference in element delays and wavefront shape between a steered beam with and without focusing. Element delays are relative to the array center.
```figure helperPlotULAWavefronts(14,1e6,1540,20,inf) title('Steered Wavefront')```
```figure helperPlotULAWavefronts(14,1e6,1540,20,0.01) title('Steered and Focused Wavefront')```
#### The Focal Region and Near/Far Boundary
In the far field, a steered array has a well-defined pattern in angle space, which is not dependent on range. In the near field, a steered (but unfocused) array has no discernabe lobe structure at all. Thanks to the nonlinear phase relationship between elements, a response that has equal magnitude at all ranges in a given direction is not possible. Instead, by focusing a beam one can obtain a small region, bounded in both angle and range, in which the response resembles a far-field response, known as the focal region. The angular position of the focal region may be controlled as easily as with a far-field beam. The position of the focal region in range is determined by the focal range, and the depth of field (DoF), which is the range extent of the region.
The figures below shows the progression of beam shape with range for focused uniform and rectangular arrays. The function `helperPlotResponseSlices` is provided to demonstrate how to generate this type of figure.
At the focal range, our beam in angle space closely resembles that of a far-field pattern.
The near/far boundary, similar in concept to other near-field/far-field boundaries, is the boundary past which focusing is not possible. Conversely, a steered but unfocused beam is not possible on the near side of the boundary. The figure below demonstrates this fact. Notice that the steered beam only begins to take shape on the far side, and the focused beam is only focused on the near side.
The range where this boundary can be found is well-documented in the medical imaging literature as ${\mathit{L}}_{\mathrm{array}}^{2}/4\lambda$, where ${\mathit{L}}_{\mathrm{array}}$ is the length of the array. For a simple uniform linear array with $\mathit{N}$ critically-spaced elements, this can be expressed as ${\mathit{N}}^{2}\lambda /16$.
#### Generating the Response for a Single Beam
This sections shows how to generate and plot a single beam. Start by setting up the phased array and other System objects. Common medical imaging ultrasound systems operate between 2 and 20 MHz, and the commonly-accepted average propagation speed of sound in soft tissue is 1540 m/s.
```rng('default') freq = 4e6; c = 1540; lambda = c/freq;```
Ultrasound transducers come in a wide variety of topologies suited for specific activities. This example simply uses a uniform linear array with critical element spacing.
```numElems = 256; elemSpacing = lambda/2; array = phased.ULA(numElems,elemSpacing);```
The System objects `phased.FocusedSteeringVector` and `phased.SphericalWavefrontArrayResponse` are used in tandem to generate steered and focused element weights, and to compute the response over some domain. Pass the array and propagation speed specification from above to the constructors. For the array response, also turn on the weights input port.
```SV = phased.FocusedSteeringVector('SensorArray',array,'PropagationSpeed',c); AR = phased.SphericalWavefrontArrayResponse('SensorArray',array,'PropagationSpeed',c,'WeightsInputPort',true);```
Now you have the minimal setup required to form and inspect a focused beam. Use a 10 degree steer in azimuth and a focal range of 40 mm.
```azSteer = 10; focalRange = 0.04;```
Use a domain that starts in front of the array and extends out to twice the focal range, and covers the length of the array in the lateral direction. The array elements lie along the Y axis, and the array normal direction is +X.
```arrayLength = numElems*elemSpacing; x = linspace(1e-3,2*focalRange,200); y = linspace(-arrayLength/2,arrayLength/2,200);```
Convert to spherical coordinates for input to the steering vector and response computation.
```[az,el,rng] = cart2sph(x,y',0); ang = rad2deg([az(:) el(:)]'); rng = rng(:)';```
Now compute the response of the focused array over the specified domain.
```weights = SV(freq,[azSteer;0],focalRange); beam = AR(freq,ang,rng,weights);```
Reshape, normalize, and use log-scale.
```beam = reshape(beam,numel(y),numel(x)); beam = beam/max(abs(beam(:))); beam = mag2db(abs(beam));```
Use the provided function `helperPlotResponse` to plot the result. The positions of the array elements are indicated by red markers.
```figure helperPlotResponse(beam,x,y,array) title('Single Steered and Focused Beam')```
The focal region is clearly visible at the specified range and angle. As with the far-field response (pattern), the magnitude of the spherical wavefront response takes into account the varying phase across elements but, unlike the far-field response, the spherical wavefront response also includes the effect of varying free-space propagation loss across elements. This is essentially a slight amplitude modulation across elements, the effect of which is visible in the beam's sidelobes. A flat gain equal to the focal range is applied to each element, so that the overall amplitude weighting on an element is the ratio of the distance between the response point and the array center to the distance from the response point to the individual element: ${\mathit{R}}_{\mathrm{resp}}/{\mathit{R}}_{\mathrm{elem}}$. For example, the contribution to the sum beam from an element located at the origin would have unit magnitude.
#### Focal Region
For a focal region to be bounded in range, the focal range must be small enough that the entire region (with extent determined by the DoF) must be closer than the near/far boundary. DoF can be expressed as a function of a related quantity, commonly seen in optics, known as the F-number, which is the ratio of the focal range to the length of the array: $\mathit{F}={\mathit{R}}_{\mathrm{foc}}/{\mathit{L}}_{\mathrm{array}}$. From this quantity, a good estimate of the DoF is ${\mathit{d}}_{\mathit{F}}=\mathrm{7}.1\lambda \text{\hspace{0.17em}}{\mathit{F}}^{2}$. For a fixed array and frequency, the DoF increases with the square of the focal range.
This section takes a look at how the DoF changes with focal range. Generate the response over an interval of focal ranges, and examine the changing DoF. The function `helperPlotBeamMarkers` will display an indication of the DoF for each focal range. The focal region is roughly elliptical, and is not centered on the focal range. Another rule of thumb can be used to find the offset from the focal range to the center of the region: ${\mathit{d}}_{\mathit{F}}/4$.
```nearField = arrayLength^2/(4*lambda); % Near/far boundary range x = linspace(1e-3,nearField*1.2,100); y = linspace(-0.01,0.01,100); coeff = 0.1:0.1:0.9; % Proportion of near/far boundary focalRanges = coeff*nearField; fnum = focalRanges/arrayLength; dof = 7.1*lambda*fnum.^2; focalRegionCenter = focalRanges + dof/4; figure for ind = 1:numel(focalRanges) beam = helperMakeSingleBeam( SV,AR,freq,0,focalRanges(ind),x,y ); helperPlotResponse(beam,x,y) caxis([-6 0]) % only view the greatest 6 dB of the beam helperPlotBeamMarkers(focalRanges(ind),focalRegionCenter(ind),nearField,dof(ind),0.001) title(sprintf('Focal Range = %d%% of Near/Far Boundary',round(coeff(ind)*100))) drawnow end```
By the time the focal range has increased to 60% of the near/far boundary, the eccentricity of the focal region has become quite large. By 80%, the focal region has intersected the near/far boundary and has essentially become an unfocused beam.
Beamwidth in the focal region, as with a far-field response, may still be roughly computed with the usual $\lambda \text{\hspace{0.17em}}/{\mathit{L}}_{\mathrm{array}}$, the ratio of wavelength to array length. Thus the width (in the lateral direction) of the focal region can be approximated with ${\mathit{R}}_{\mathrm{foc}}\lambda /{\mathit{L}}_{\mathrm{array}}$.
### Single-Line Acquisition with Linear Subarray Shifting
#### A-scans and Image Formation
Unlike radar systems, where direction of arrival can be estimated efficiently through beamforming of far-field signals, the near-field beamforming and latency requirements of ultrasound systems often necessitate a simpler strategy to locate the source of returned energy. A common class of collection strategy involves multiple A-scans, reflectivity profiles along a given line segment. The placement of these lines within the formed image is determined simply by the known position of the beam.
To form a rectangular image, as is done in this example, lineary subarray shifting can be used. With this method a subset of the array elements (a subarray) is used for each pulse, with no steering, to get a range profile originating at the center of the subarray and extending in the axial direction. Successive lines are formed by shifting the subarray selection to a different set of elements.
The choice of focal range can be considered separately from beam pointing. Some systems may keep a fixed focal range, or use dynamic focusing on receive along with apodization or windowing to generate a broad image that covers much of the near-field region. In this example focal range is kept fixed while the lateral position of the subarray is varied.
The helper class `helperSubarray` is provided to emulate subarray selection and simplify the simulation loop. This class keeps track of which elements belong to the current subarray and handles the necessary transforms between the global and subarray frames.
#### Image Formation
In order to demonstrate the effects of focused beamforming, this example uses a simple image formation strategy that constructs each range profile by quantizing and accumulating the response at each pulse, then inserting that profile into the completed image based on the location of the subarray. This simulates an ideal delta pulse in free space, which allows for a comparison of lateral resolution inside and outside the focal region. This method disregards the effects of waveform choice and multipath reflections, and treats scatterers as perfect point isotropic reflectors.
#### Simulation
The same system parameters will be used as in the previous section. Each subarray will consist of 64 elements. The subarray starts at the end of the array and is shifted by one element on each pulse.
```numSubElems = 64; subarray = helperSubarray(array,numSubElems);```
If subarray is shifted by one element on each pulse and all contiguous subarrays are covered, the total number of pulses will be
`numPulses = numElems - numSubElems + 1`
```numPulses = 193 ```
Following the analysis in the previous section, check the focal region parameters for this subarray. Get the subarray length, near/far boundary, DoF, and lateral width of the focal region.
```subarrayLength = numSubElems*elemSpacing; nearFieldSub = subarrayLength^2/(4*lambda); % Near/far boundary for the subarray fnumSub = focalRange/subarrayLength; dofSub = 7.1*lambda*fnumSub.^2```
```dofSub = 0.0288 ```
`widthSub = lambda/subarrayLength*focalRange`
```widthSub = 0.0013 ```
The subarray beam has a DoF of about 28.8 mm, and the lateral width of the focal region is about 1.3 mm. Check that the focal region is well within the near/far boundary
`boundedFocalRegion = focalRange + dofSub < nearFieldSub`
```boundedFocalRegion = logical 1 ```
To demonstrate the primary usefulness of a focused beam, decreased beamwidth in the focal region, use multiple parallel lines of scatterers along the axial direction (depth lines). Specify the desired max depth of scatterers, and use the provided helper function, `helperGetResponsePoints`, to get the scatterer positions. Let all scatterers have reflectivity with unit amplitude. The scatterer positions are perturbed to avoid artifacting due to symmetry.
For the lateral spacing of the lines, use 4 times the calculated focal region width. Because the subarray is simply shifted by one element at a time, which is a shorter distance than our beam width in the focal region, return from each line of scatterers shows up in more than one row of the image, making them appear to have greater width.
```maxDepth = nearFieldSub; lineSpacing = 4*widthSub; [sx,sy] = helperGetResponsePoints(maxDepth,arrayLength,lambda,lineSpacing);```
To visualize the scene, plot the scatterer positions along with the array elements.
```figure plot(subarray) hold on plot(sx,sy,'.') hold off legend('Array Elements','Initial Subarray','Scatterers') xlabel('Axial Distance') ylabel('Lateral Position')```
To form a range profile and capture the effects of interference from sidelobe return, range sampling parameters must be defined. Modern ultrasound systems use a relatively high sampling frequency, on the same order as the center frequency of the transmitted waveform. Use a range bin size of 1 mm, corresponding to a sampling rate of about 1.5 MHz. The provided helper function `helperFormRangeProfile` is used to form the range profile from the array response data.
```rangeBinSize = 1e-3; Fs = c/rangeBinSize; rangeBins = 0:rangeBinSize:maxDepth; numRangeSamples = numel(rangeBins);```
Get the scatterer positions in spherical coordinates (angles in degrees) for input to `SphericalWavefrontArrayResponse`.
```[respAng,~,respRng] = cart2sph(sx,sy,0); respAng = rad2deg(respAng(:)'); respRng = respRng(:)';```
Each loop of the simulation involves computing weights for the current subarray, computing the response, forming a range profile, and forming the image line by line. We'll also apply range-dependent gain for uniform brightness (see `helperFormRangeProfile`).
```im = zeros(numPulses,numRangeSamples); center = zeros(3,numPulses); for pulse = 1:numPulses center(:,pulse) = subarray.center; % Center position of our current subarray [focAzGlobal,~,focRngGlobal] = subarray.localToGlobalSph( 0,0,focalRange ); % Angle and range to current focal point weights = SV(freq,[focAzGlobal;0],focRngGlobal); weights(~subarray.selection) = 0; % Zero-out weights for unused elements resp = AR(freq,respAng,respRng,weights); resp = resp./respRng(:); % Undo normalization to use actual propagation loss im(pulse,:) = helperFormRangeProfile(resp,sx,sy,center(:,pulse),rangeBins); % Add line to image if pulse < numPulses subarray.shift(1) % Shift subarray if there are pulses remaining end end```
Normalize and plot the image, along with an overlay of the scatterer positions.
```im = im/max(abs(im(:))); figure subplot(1,2,1) helperPlotResponse(mag2db(abs(im)),rangeBins,center(2,:)) title('Linear Subarray Shift Image') subplot(1,2,2) helperPlotResponse(mag2db(abs(im)),rangeBins,center(2,:)) hold on plot(sx,sy,'.r','markersize',1) hold off title('Scatterer Overlay') set(gcf,'Position',get(gcf,'Position')+[0 0 560 0]);```
The depth lines are resolvable about the focal range, over a range interval roughly equal to the computed DoF for the subarray beam. Away from the focal point, the parallel lines of scatterers quickly become indistinguishable thanks to the wide angular spread of the beam outside the focal region.
Note that, though all the scatterers were used to compute energy return, not all lines are visible due to the clipping between the full array size and the extent of subarray center positions. A wider total field of view would be obtainable with a shorter subarray, at the cost of reduced lateral resolution.
### Conclusion
This example introduced two System objects for computing focused weights and for computing the non-far-field response of an array with spherical wavefronts. It showed how to examine some basic characteristics of a focused beam, and how to generate a basic image to visualize the effect of a focused beam on lateral resolution with a linear subarray shift collection method.
### References
[1] Demi, Libertario. “Practical Guide to Ultrasound Beam Forming: Beam Pattern and Image Reconstruction Analysis.” Applied Sciences 8, no. 9 (September 3, 2018): 1544. https://doi.org/10.3390/app8091544
[2] Ramm, O. T. Von, and S. W. Smith. “Beam Steering with Linear Arrays.” IEEE Transactions on Biomedical Engineering BME-30, no. 8 (August 1983): 438–52.
### Helper Functions
#### helperMakeSingleBeam
```function [beam,x,y] = helperMakeSingleBeam( SV,AR,freq,azSteer,focalRange,x,y ) % Get the element weighting for a single beam and compute the response weights = SV(freq,[azSteer;0],focalRange); % Domain of response if nargin < 6 x = linspace(1e-3,2*focalRange,200); end if nargin < 7 pos = SV.SensorArray.getElementPosition; halfy = max(pos(2,:))*1.2; y = linspace(-halfy,halfy,200); end [az,el,rng] = cart2sph(x,y',0); ang = rad2deg([az(:) el(:)]'); rng = rng(:)'; % Generate response beam = AR(freq,ang,rng,weights); beam = reshape(beam,numel(y),numel(x)); % Normalize and use log scale beam = beam/max(abs(beam(:))); beam = mag2db(abs(beam)); end```
#### helperPlotResponse
```function helperPlotResponse(R,x,y,array) % Plot the response, R, on the domain defined by x and y. imagesc(x,y,R) set(gca,'ydir','normal') caxis([-32 0]) xlabel('Axial Distance') ylabel('Lateral Position') if nargin > 3 pos = getElementPosition(array); hold on h = plot(pos(1,:),pos(2,:),'.r'); hold off xl = xlim; xlim([min(pos(1,:)) xl(2)]) legend(h,'Array Elements','Location','southeast','AutoUpdate','off') end end```
#### helperPlotBeamMarkers
```function helperPlotBeamMarkers(focalRange,center,nearField,dof,offset) % Put informative markers on a beam plot line([center-dof/2 center+dof/2],[offset offset],'color','white') line([center-dof/2 center-dof/2],[0 offset],'color','white') line([center+dof/2 center+dof/2],[0 offset],'color','white') line([focalRange focalRange],ylim,'color','red') line([nearField nearField],ylim,'color','cyan') end```
#### helperGetResponsePoints
```function [sx,sy] = helperGetResponsePoints( maxDepth,arrayLength,lambda,dy ) % Make parallel lines of scatterers along X sx = linspace(0.001,maxDepth,400); sy = -arrayLength/2:dy:arrayLength/2; [sx,sy] = meshgrid(sx,sy); sx = sx(:); sy = sy(:); sx = sx + (rand(size(sx))-1/2)*lambda; sy = sy + (rand(size(sy))-1/2)*lambda; end```
#### helperFormRangeProfile
```function rangeProf = helperFormRangeProfile(resp,sx,sy,center,rangeBins) % This helper function quantizes a response in range, coherently % accumulates the return in each bin, and applies amplitude weighting per % range bin rangeBinSize = rangeBins(2) - rangeBins(1); numRangeSamples = numel(rangeBins); % Range of scatterers relative to subarray center scatRngRel = sqrt((center(1)-sx).^2 + (center(2)-sy).^2); % Quantize scatterer ranges into fast-time sampling vector scatRidx = 1 + floor(scatRngRel/rangeBinSize); % Only keep samples below max depth I = scatRidx <= numRangeSamples; scatRidx = scatRidx(I); resp = resp(I); % Accumulate return into fast-time sampling grid rangeProf = accumarray(scatRidx,resp,[numRangeSamples 1]); rangeProf = rangeProf'; % Apply range-dependent gain rangeProf = rangeProf.*rangeBins; end```
#### helperPlotULAWavefronts
```function helperPlotULAWavefronts( numElems,f,c,az,r ) % Plot the wavefronts for the given ULA with ArrayAxis 'y', for the given % azimuth angle and focal range. % % For the far-field wavefront, use inf for focal range lambda = c/f; array = phased.ULA(numElems,lambda/2); pos = getElementPosition(array); arrayLength = max(pos(2,:)) - min(pos(2,:)); % get relative path lengths if isinf(r) L = phased.internal.elemdelay(pos,c,[az;0])*c; else L = phased.internal.sphericalelemdelay(pos,c,[az;0],r)*c; end % plot element positions plot(pos(1,:),pos(2,:),'oblue'); hold on; % if near field, plot source if ~isinf(r) [src(1,1),src(2,1),src(3,1)] = sph2cart(az*pi/180,0,r); plot(src(1),src(2),'*r','markersize',10); end % wavefront marker width s = lambda/6; % far field prop path if isinf(r) [los(1,1),los(2,1),los(3,1)] = sph2cart(az*pi/180,0,1); end for ind = 1:size(pos,2) % for each element p = pos(:,ind); if isinf(r) src = p + los*arrayLength; end path = src - p; path = path/norm(path); wp = p + path*L(ind); % position of wavefront % prop path line([wp(1) src(1)],[wp(2) src(2)],'color','black','linestyle','--'); % wavefront marker u = cross([0;0;1],path)*s; line([wp(1)-u(1) wp(1)+u(1)],[wp(2)-u(2) wp(2)+u(2)],'color','magenta'); end hold off; grid on; axis equal; if isinf(r) legend('Elements','Prop Path','Wavefronts','Location','SouthEast'); else legend('Elements','Focal Point','Prop Path','Wavefronts','Location','SouthEast'); end end```
#### helperPlotResponseSlices
```function helperPlotResponseSlices % Demonstrates how to visualize range slices of a spherical wavefront response f = 2e6; c = 1540; lambda = freq2wavelen(f,c); array = phased.URA([32 32],lambda/2); elemPos = array.getElementPosition; focalRange = 0.03; sampleRanges = .01:.01:.05; % domain of each slice azSteer = -20; elSteer = 20; az = azSteer + (-30:.1:30); el = elSteer + (-30:.1:30); [az,el] = meshgrid(az,el); ang = [az(:) el(:)]'; [x,y,z] = sph2cart(az*pi/180,el*pi/180,1); SV = phased.FocusedSteeringVector('SensorArray',array,'PropagationSpeed',c); AR = phased.SphericalWavefrontArrayResponse('SensorArray',array,'PropagationSpeed',c,'WeightsInputPort',true); w = SV(f,[azSteer;elSteer],focalRange); for ind = 1:numel(sampleRanges) resp = AR(f,ang,sampleRanges(ind),w); resp = resp / array.getNumElements; resp = reshape(resp,size(x)); alpha = 1 - (abs(sampleRanges(ind) - focalRange)/(max(sampleRanges)-min(sampleRanges))); % transparency surf(x*sampleRanges(ind),y*sampleRanges(ind),z*sampleRanges(ind),mag2db(abs(resp)),'FaceAlpha',alpha) hold on shading flat end % plot element positions and boresight vector caxis([-32 0]) plot3(elemPos(1,:),elemPos(2,:),elemPos(3,:),'.black','markersize',4); [b(1),b(2),b(3)] = sph2cart(azSteer*pi/180,elSteer*pi/180,max(sampleRanges)*1.2); quiver3(0,0,0,b(1),b(2),b(3),'black','autoscale','off') axis equal axis off hold off set(gca,'view',[-70 22]) end ``` | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 10, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.6474094986915588, "perplexity": 957.6633636054457}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": false}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2022-49/segments/1669446710473.38/warc/CC-MAIN-20221128034307-20221128064307-00279.warc.gz"} |
https://arabianautos.qa/challis-fabric-xini/b34f1b-how-to-find-orthogonal-matrix | To nd the matrix of the orthogonal projection onto V, the way we rst discussed, takes three steps: (1) Find a basis ~v 1, ~v 2, ..., ~v m for V. (2) Turn the basis ~v i into an orthonormal basis ~u i, using the Gram-Schmidt algorithm. To test whether a matrix is an orthogonal matrix, we multiply the matrix to its transpose. , Then we multiply the transpose with given matrix. You can also try to input your own matrix to test whether it is an orthogonal matrix or not. Title: Finding the Nearest Orthonormal Matrix Author: Berthold K.P. Orthogonal matrix is important in many applications because of its properties. We can define an inner product on the vector space of all polynomials of degree at most 3 by setting. Orthogonal matrix is an important matrix in linear algebra, it is also widely used in machine learning. 2. Video transcript. Es ist offensichtlich, dass Q orthogonal ist, da die beiden Spaltenvektoren orthogonal sind. of the Damit ist die Inverse einer orthogonalen Matrix gleichzeitig ihre Transponierte. If matrix Q has n rows then it is an orthogonal matrix (as vectors q1, q2, q3, …, qn are assumed to be orthonormal earlier) Properties of Orthogonal Matrix. Orthogonal matrix multiplication can be used to represent rotation, there is an equivalence with quaternion multiplication as described here. Find the inverse matrix of … An orthogonal matrix is the real specialization of a unitary matrix, and thus always a normal matrix.Although we consider only real matrices here, the definition can be used for matrices with entries from any field.However, orthogonal matrices arise naturally from dot products, and for matrices of complex numbers that leads instead to the unitary requirement. A matrix can be tested to see if it is orthogonal using the Wolfram Language code: OrthogonalMatrixQ[m_List?MatrixQ] := (Transpose[m].m == IdentityMatrix @ Length @ m) The rows of an orthogonal matrix are an orthonormal basis. >. Index If, it is 1 then, matrix A may be the orthogonal matrix. Some important properties of orthogonal matrix are, See also Let W be a subspace of R n and let x be a vector in R n. spectral decomposition, Rate this tutorial or give your comments about this tutorial, The row vector and the column vector of matrix, Both Hermitian and Unitary matrix (including. If you are at an office or shared network, you can ask the network administrator to run a scan across the network looking for misconfigured or infected devices. What is Orthogonal Matrix? The eigenvalues of the orthogonal matrix will always be $$\pm{1}$$. Die Matrix ist also orthogonal, weil die Multiplikation der Matrix mit der transponierten Matrix die Einheitsmatrix ergibt. Orthogonal Matrix Example. Another way to prevent getting this page in the future is to use Privacy Pass. From introductory exercise problems to linear algebra exam problems from various universities. Diese Matrix beschreibt eine Drehung um den Winkel −θ. That is, if and only if . The matrix in problem statement (not step one) is for the previous problem. To test whether a matrix is an orthogonal matrix, we multiply the matrix to its transpose. < Orthogonal matrices preserve angles and lengths. So let me call my set B. Vocabulary words: orthogonal decomposition, orthogonal projection. An orthogonal matrix … This is true because d vectors will always be sufficient be needed to span a d-dimensional vector space. are orthogonal matrices. This can be generalized and extended to 'n' dimensions as described in group theory. Performance & security by Cloudflare, Please complete the security check to access. One way to think about a 3x3 orthogonal matrix is, instead of a 3x3 array of scalars, as 3 vectors. Solution: The orthogonal projection matrix is also detailed and many examples are given. Calculate and verify the orthonormal basis vectors for the range of a full rank matrix. Problems of Orthogonal Bases. To check for its orthogonality steps are: Find the determinant of A. Es gilt detQ = cos2 ϕ +sin2 ϕ = 1. Your IP: 78.47.248.67 0 0 1 0 1 0 For example, if Q =1 0 then QT=0 0 1. Finally we check if the matrix obtained is identity or not. Next Cloudflare Ray ID: 60a7cf86683fdfbf Eigen vectors inverse The concept of two matrices being orthogonal is not defined. Let given square matrix is A. Q⋅QT = E Q ⋅ Q T = E Die Determinante einer orthogonalem Matrix nimmt entweder den Wert +1 oder -1 an. Example 1. To create random orthogonal matrix as in the interactive program below, I created random | matrix and compute the modal matrix from Pictures: orthogonal decomposition, orthogonal projection. Let W be a subspace of R4 with a basis {[1011],[0111]}. Simple Solution : The idea is simple, we first find transpose of matrix. This covers about orthogonal matrix Its definition and properties. Note that this is an n n matrix, we are multiplying a column vector by a row vector instead of the other way around. Comment(8) Anonymous. Gram-Schmidt example with 3 basis vectors. Stack Exchange network consists of 176 Q&A communities including Stack Overflow, the largest, most trusted online community for developers to learn, share their knowledge, and build their careers.. Visit Stack Exchange Find an orthonormal basis of W. (The Ohio State University, Linear Algebra Midterm) Add to solve later Sponsored Links If n>d, regardless of the size, as long as n>d, we can never find a set of n vectors in a d-dimensional space that are orthogonal. If we try the orth trick, it will produce an array of size d by d, thus a SQUARE matrix. Please enable Cookies and reload the page. symmetric Recipes: orthogonal projection onto a line, orthogonal decomposition by solving a system of equations, orthogonal projection via a complicated matrix product. Spiegelung. The concept of orthogonality for a matrix is defined for just one matrix: A matrix is orthogonal if each of its column vectors is orthogonal to all other column vectors and has norm 1. transpose Singular Value Decomposition A matrix is orthogonal if the In this tutorial, we will dicuss what it is and how to create a random orthogonal matrix with pyhton. If a matrix A is an orthogonal matrix, it shoud be n*n. The feature of an orthogonal matrix A. b. A square orthonormal matrix Q is called an orthogonal matrix. Overview. In fact, given any … If the result is an identity matrix, then the input matrix is an orthogonal matrix. You can imagine, let's say that we have some vector that is a linear combination of these guys right here. 7 Finding stationary distribution of a markov process given a transition probability matrix The Gram-Schmidt process. Therefore, the value of determinant for orthogonal matrix will be either +1 or -1. concatenation Suppose that is an orthogonal basis for the column space of . The 1/0 indicate where values are allowed in the result matrix. 2. • is equal to its The vectors in are orthogonal while are not. Let us see an example of the orthogonal matrix. . That is, each row has length one, and are mutually perpendicular. Similarly, the columns are also an orthonormal basis. Orthogonal Complements and Projections Recall that two vectors in are perpendicular or orthogonal provided that their dot product vanishes. How to fill in a matrix given diagonal and off-diagonal elements in r? , that is So let's say vector w is equal to some linear combination of these vectors right here. Fact 5.3.3 Orthogonal transformations and orthonormal bases a. • Let. Thus, matrix Basic to advanced level. The concept of orthogonality for a matrix is defined for just one matrix: A matrix is orthogonal if each of its column vectors is orthogonal to all other column vectors and has norm 1. orthogonal vector Basis vectors. Eigen-everything. Define a matrix and find the rank. Previous , When you click Random Example button, it will create random input matrix to provide you with many examples of both orthogonal and non-orthogonal matrices. Um eine orthogonale Matrix bestimmen zu können, überprüfst du die Formel von oben. is an orthogonal matrix. Eine orthogonale Matrix ist in der linearen Algebra eine quadratische, reelle Matrix, deren Zeilen- und Spaltenvektoren orthonormal bezüglich des Standardskalarprodukts sind. Horn Subject: Painful Way to Solve Photogrammetric Problems Keywords: Orthonormal matrix, Rotation, Photogrammetry, Least Squares Fitting, Projective Geometry, Matrix Square Root, Two step … I need to find an orthogonal matrix Q, so that when applying M_2 = Q M_1 Q^-1 the matrix M_2 does not contain any values at the zero positions of P. The other way is possible, M_2 may contain a zero, where P is one. Demzufolge gilt Q−1 = QT = cosϕ sinϕ −sinϕ cosϕ . Also given a symmetric prototype matrix P, containing ones and zeroes. Dafür musst du zunächst die transponierte Matrix berechnen und diese dann mit multiplizieren. If the result is an identity matrix, then the input matrix is an orthogonal matrix. How to find an orthogonal matrix? If you are on a personal connection, like at home, you can run an anti-virus scan on your device to make sure it is not infected with malware. Orthogonal Matrix (1) The Definition of The Orthogonal Basis. If Q is an orthogonal matrix, then, |Q| = ±1. Thus, matrix is an orthogonal matrix. Orthogonale Matrizen k¨onnen auch Spiegelungen an Geraden beschreiben. A linear transformation T from Rn to Rn is orthogonal iff the vectors T(e~1), T(e~2),:::,T(e~n) form an orthonormal basis of Rn. Since computing matrix inverse is rather difficult while computing matrix transpose is straightforward, orthogonal matrix make difficult operation easier. Example using orthogonal change-of-basis matrix to find transformation matrix. : We study orthogonal transformations and orthogonal matrices. Suppose we have a set of vectors {q1, q2, …, qn}, which is orthogonal if, then this basis is called an orthogonal basis. An n £ n matrix A is orthogonal iff its columns form an orthonormal basis of Rn. Example: Prove Q = $$\begin{bmatrix} cosZ & sinZ \\ -sinZ & cosZ\\ \end{bmatrix}$$ is orthogonal matrix. Next lesson. You may need to download version 2.0 now from the Chrome Web Store. Proof Part(a):) If T is orthogonal, then, by definition, the Let's say I've got me a set of vectors. Completing the CAPTCHA proves you are a human and gives you temporary access to the web property. . The objective is to find an orthogonal basis for the column space of the following matrix: Use Gram-Schmidt Process to find an orthogonal basis for the column space of segregate the columns of the matrix as . The interactive program below is designed to answers the question whether the given input matrix is an orthogonal matrix. If Q is square, then QTQ = I tells us that QT= Q−1. Gram-Schmidt process example. Well, if you're orthogonal to all of these members, all of these rows in your matrix, you're also orthogonal to any linear combination of them. | The concept of two matrices being orthogonal is not defined. (3) Your answer is P = P ~u i~uT i. 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( not step one ) is for the column space of all polynomials of degree at most by! | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 1, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.8998816609382629, "perplexity": 1265.716874724164}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 5, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2021-17/segments/1618038067400.24/warc/CC-MAIN-20210412113508-20210412143508-00320.warc.gz"} |
https://www.mockbank.com/bulletin/computer-knowledge-quiz-october-28th-2015/ | The Computer Knowledge (CK) Section is covered in many banking/recruitment exams.
The following quiz helps you brush up your computer knowledge skills.
Computer Knowledge section consists of following categories: Windows, Microsoft Office (Word, Excel), Networking, Basic Hardware and Software, DBMS etc.ut
Today’s quiz is on Microsoft Windows
Answer the quiz wisely and remember to post your scores in the comments below. Any questions or related information is welcome.
1. In Windows operating system after you double-click a character on the grid of characters, keyboard shortcut DOWN ARROW is used for
Question 1 of 10
2. In Windows operating system after you double-click a character on the grid of characters, keyboard shortcut PAGE UP is used for
Question 2 of 10
3. In Windows operating system after you double-click a character on the grid of characters, keyboard shortcut PAGE DOWN is used for
Question 3 of 10
4. In Windows operating system after you
double-click a character on the grid of characters,
keyboard shortcut HOME is used for
Question 4 of 10
5. In Windows operating system after you double-click a character on the grid of characters, keyboard shortcut END is used for
Question 5 of 10
6. In Windows operating system after you
double-click a character on the grid of characters,
keyboard shortcut CTRL+HOME is
used for
Question 6 of 10
7. In Windows operating system after you
double-click a character on the grid of characters,
keyboard shortcut CTRL+END is
used for
Question 7 of 10
8. In Windows operating system after you
double-click a character on the grid of characters,
keyboard shortcut SPACEBAR is used
for
Question 8 of 10
9. In Windows operating system to copy something
the following shortcut is used
Question 9 of 10
10. In Windows operating system to cut something
the following shortcut is used-
Question 10 of 10 | {"extraction_info": {"found_math": false, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.8305133581161499, "perplexity": 4489.019942959612}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2021-10/segments/1614178367949.58/warc/CC-MAIN-20210303230849-20210304020849-00183.warc.gz"} |
https://www.calculatoratoz.com/en/intake-air-density-calculator/Calc-37496 | ## Intake air density Solution
STEP 0: Pre-Calculation Summary
Formula Used
Air density at intake = Intake air pressure/([R]*Intake air temperature)
ρa = Pa/([R]*Ta)
This formula uses 1 Constants, 3 Variables
Constants Used
[R] - Universal gas constant Value Taken As 8.31446261815324 Joule / Kelvin * Mole
Variables Used
Air density at intake - (Measured in Kilogram per Cubic Meter) - Air density at intake is defined as the density of air recorded at intake manifold at atmospheric pressure and room temperature.
Intake air pressure - (Measured in Pascal) - Intake air pressure is defined as the pressure of the air drawn at intake manifold.
Intake air temperature - (Measured in Kelvin) - Intake air temperature is defined as the temperature of the drawn air at inlet manifold.
STEP 1: Convert Input(s) to Base Unit
Intake air pressure: 150000 Pascal --> 150000 Pascal No Conversion Required
Intake air temperature: 313 Kelvin --> 313 Kelvin No Conversion Required
STEP 2: Evaluate Formula
Substituting Input Values in Formula
ρa = Pa/([R]*Ta) --> 150000/([R]*313)
Evaluating ... ...
ρa = 57.6385088064182
STEP 3: Convert Result to Output's Unit
57.6385088064182 Kilogram per Cubic Meter --> No Conversion Required
57.6385088064182 Kilogram per Cubic Meter <-- Air density at intake
(Calculation completed in 00.016 seconds)
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## Credits
Ramaiah University of Applied Sciences (RUAS), bangalore
Syed Adnan has created this Calculator and 100+ more calculators!
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## < 10+ For 4 Stroke Engine Calculators
Indicated Power of Four-stroke Engine
## Indicated Power of Four-stroke Engine
Formula
"IP" = ("k"*"MEP"*"L"*"A"*("N"))/(2)
Example
"0.001106kW"=("4"*"0.005kPa"*"8.8cm"*"30cm²"*("4000r/"min""))/(2)
Calculator
LaTeX
Indicated Power = (Number of Cylinders*Mean Effective Pressure*Stroke Length*Area of Cross Section*(Engine Speed))/(2)
Volumetric Efficiency for 4S engines
## Volumetric Efficiency for 4S engines
Formula
"VE" = ((2*"m"_{"af"})/("ρ"_{"a"}*"V"_{"s"}*("N")))*100
Example
"0.00179"=((2*"0.9kg/s")/("1.20kg/cm³"*"200cm³"*("4000r/"min"")))*100
Calculator
LaTeX
Volumetric Efficiency = ((2*Air Mass Flow Rate)/(Intake Air Density*Piston swept volume*(Engine Speed)))*100
Brake Mean Effective Pressure of 4S Engines given Brake power
## Brake Mean Effective Pressure of 4S Engines given Brake power
Formula
"P"_{"mb"} = (2*"BP")/("L"*"A"*("N"))
Example
"0.144686kPa"=(2*"0.008kW")/("8.8cm"*"30cm²"*("4000r/"min""))
Calculator
LaTeX
Brake Mean Effective Pressure = (2*Brake Power)/(Stroke Length*Area of Cross Section*(Engine Speed))
Work done per cycle in ic engine
## Work done per cycle in ic engine
Formula
"W" = ("P"*"n"_{"R"})/"N"
Example
"0.4kJ"=("100kW"*"2")/"500"
Calculator
LaTeX
Work done per cycle in ic engine = (Indicated engine power*Crankshaft revolutions per power stroke)/Engine Speed in rpm
Fuel conversion efficiency
## Fuel conversion efficiency
Formula
"η"_{"f"} = "W"/("m"_{"f"}*"Q"_{"HV"})
Example
"0.4"="100kJ"/("0.005"*"50000kJ/kg")
Calculator
LaTeX
Fuel conversion efficiency = Work done per cycle in ic engine/(Mass of fuel added per cycle*Heating value of the fuel)
Combustion efficiency
## Combustion efficiency
Formula
"η"_{"c"} = "Q"_{"in"}/("m"_{"f"}*"Q"_{"HV"})
Example
"0.6"="150kJ/kg"/("0.005"*"50000kJ/kg")
Calculator
LaTeX
Combustion efficiency = Heat added by combustion per cycle/(Mass of fuel added per cycle*Heating value of the fuel)
Bmep given engine torque
## Bmep given engine torque
Formula
"Bmep" = (2*pi*"T"*"N")/"s"_{"p"}
Example
"81881.16Pa"=(2*pi*"140000N*mm"*"4000r/"min"")/"4.5m/s"
Calculator
LaTeX
Bmep = (2*pi*Engine torque*Engine Speed)/Mean Piston Speed
Thermal efficiency of IC engine
## Thermal efficiency of IC engine
Formula
"η"_{"th"} = "W"/"Q"_{"in"}
Example
"0.666667"="100kJ"/"150kJ/kg"
Calculator
LaTeX
Thermal efficiency of ic engine = Work done per cycle in ic engine/Heat added by combustion per cycle
Fuel conversion efficiency given thermal conversion efficiency
## Fuel conversion efficiency given thermal conversion efficiency
Formula
"η"_{"f"} = "η"_{"c"}*"η"_{"t"}
Example
"0.4"="0.80"*"0.50"
Calculator
LaTeX
Fuel conversion efficiency = Combustion efficiency*Thermal conversion efficiency
Horsepower of engine
## Horsepower of engine
Formula
"HP" = ("T"*"E"_{"rpm"})/5252
Example
"13.95732"=("140000N*mm"*"5000r/"min"")/5252
Calculator
LaTeX
Horsepower of engine = (Engine torque*Engine rpm)/5252
## Intake air density Formula
Air density at intake = Intake air pressure/([R]*Intake air temperature)
ρa = Pa/([R]*Ta)
## What is intake air density?
Intake air density is the density of air recorded at intake manifold at atmospheric pressure and room temperature.
## How to Calculate Intake air density?
Intake air density calculator uses Air density at intake = Intake air pressure/([R]*Intake air temperature) to calculate the Air density at intake, The Intake air density formula is defined as the density of air recorded at intake manifold at atmospheric pressure and room temperature. Air density at intake is denoted by ρa symbol.
How to calculate Intake air density using this online calculator? To use this online calculator for Intake air density, enter Intake air pressure (Pa) & Intake air temperature (Ta) and hit the calculate button. Here is how the Intake air density calculation can be explained with given input values -> 57.63851 = 150000/([R]*313).
### FAQ
What is Intake air density?
The Intake air density formula is defined as the density of air recorded at intake manifold at atmospheric pressure and room temperature and is represented as ρa = Pa/([R]*Ta) or Air density at intake = Intake air pressure/([R]*Intake air temperature). Intake air pressure is defined as the pressure of the air drawn at intake manifold & Intake air temperature is defined as the temperature of the drawn air at inlet manifold.
How to calculate Intake air density?
The Intake air density formula is defined as the density of air recorded at intake manifold at atmospheric pressure and room temperature is calculated using Air density at intake = Intake air pressure/([R]*Intake air temperature). To calculate Intake air density, you need Intake air pressure (Pa) & Intake air temperature (Ta). With our tool, you need to enter the respective value for Intake air pressure & Intake air temperature and hit the calculate button. You can also select the units (if any) for Input(s) and the Output as well.
Let Others Know | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 1, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.8063032031059265, "perplexity": 8813.829402229429}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2023-06/segments/1674764499911.86/warc/CC-MAIN-20230201045500-20230201075500-00842.warc.gz"} |
https://marcofrasca.wordpress.com/2009/04/28/ | ## A sound confirmation of Yang-Mills scenario
28/04/2009
Today arxiv contains a very interesting paper by Attilio Cucchieri and Tereza Mendes (see here). They do a significant lattice computation for a SU(2) Yang-Mills theory in 3 and 4 dimensions. Quarks are absent (quenched approximation). Their aim is to verify the current emerging scenario in a particular situation where the coupling on the lattice is taken to go to infinity ($\beta=0$). This case, as pointed out by the authors, is unphysical but is a quite interesting test-bed for the behavior of the two-point functions of the theory (gluon and ghost propagators). They do not aim to check the running coupling as this, currently, is matter of hot debate yet.
I would like to remember what is at stake today about this question. For some years there has been the strong conviction that the gluon propagator should go to zero and ghost propagator should go to infinity faster than the free propagator (conformal solution). This was needed to confirm two confining scenarios that were commonly accepted by the community. Most of these results emerged from an idea due to Gribov that there remains an ambiguity in the gauge also after it is fixed. Taking into account Gribov ambiguity provoked a flourishing of papers all reaching similar conclusions. At that time, due to the small achievable volumes, lattice computations were not able to clarify the situation even if the gluon propagator was never seen to tend to zero in a significant way. As increasing volumes made available a completely new scenario emerged. People obtained that the gluon propagator indeed reaches a finite value at zero momentum while the ghost propagator is seen to behave as that of a free particle (decoupling solution). A commonly accepted definition of running coupling was seen to converge to zero making the theory trivial.
This emerging data prompted several explanations. People started to criticize these lattice computations as maybe there was an accumulation of Gribov copies that modify the right results into the observed ones. Maybe the fixing gauge algorithms should be better analyzed and so on. People from Australia (see here and here) claimed that low energy data should not be trusted. Discarding them one finds again the conformal solution. Cucchieri and Mendes give a sound answer to all these doubts. Indeed, it is not clear why in 2 dimensions one gets the conformal solutions but not in 3 and 4 dimensions, notwithstanding the code used to do these computations is always the same. Further, any reason adduced by Australian group to remove low energy data is proved substantially unfounded and the results obtained by Cucchieri and Mendes represent a correct picture of the case $\beta=0$ for 3 and 4 dimensions. Indeed, Cucchieri and Mendes show that Gribov copies play no role in the scenario seen at low energies for Yang-Mills theory. This is a crucial point that has been source for misleading research for a lot of years.
So, let us take a look at the scenario found by Cucchieri and Mendes. These authors consider a maximum lattice dimensions of $100^3$ for 3 dimensions and $64^4$ for 4 dimensions. They show without any doubt that one gets the decoupling solution: The gluon propagator reaches a finite value at zero momentum and the ghost propagator is that of a free particle. What is more interesting here are the fits. For the propagator they fit to a sum of Stingl-forms
$D(x)=\sum_{i=1,2}c_i\cos(b_i+\lambda_i x)e^{-\lambda_i x}$
and for the ghost propagator
$G(p)=[a-b\log(p^2+m^2)]/p^2$
being m the gluon mass. The authors tried to avoid to fix the values of their computations with experimental data. As you know, the relevant parameter here is $\sqrt{\sigma}$, the string tension. Notwithstanding this operative choice, they get for the gluon mass the following values
$m=0.499 GeV$
using only data with $p^2<4 GeV$ and
$m=0.466 GeV$
using all data. I hope that now some bell is ringing for you as this is the mass of the $\sigma$ resonance. This resonance is not seen by people doing quenched computations to obtain the spectrum of a pure Yang-Mills theory. Why? What are they missing with respect to Cucchieri and Mendes? This should not become a longstanding question. We need an answer right now.
Now, take a look at the fit of the gluon propagator. Try to do a Fourier transform and you will get back something like
$D(p)=\frac{A}{(p+\lambda_1)^2+\lambda_1^2}+\frac{B}{(p+\lambda_2)^2+\lambda_2^2}$
and this is shockingly similar to my propagator having the general form
$D(p)=\sum_nB_n\frac{1}{p^2+m_n^2},$
that is a sum of free particle propagators!
I should say that I am somewhat impressed by Cucchieri and Mendes results. They showed that the decoupling scenario is the right one in the physical case of 4 dimensions. My view is that we should move on from the current position and try to find the theoretical framework that better fits the data. It goes without saying what is the one I am supporting. | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 13, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.8320116400718689, "perplexity": 506.9316440759026}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2022-21/segments/1652662526009.35/warc/CC-MAIN-20220519074217-20220519104217-00203.warc.gz"} |
http://www.opensource.apple.com/source/MITKerberosShim/MITKerberosShim-54/PrivateKerberos/kim_types.h | # kim_types.h [plain text]
/*
* Copyright 2005-2006 Massachusetts Institute of Technology.
*
* Export of this software from the United States of America may
* require a specific license from the United States Government.
* It is the responsibility of any person or organization contemplating
* export to obtain such a license before exporting.
*
* WITHIN THAT CONSTRAINT, permission to use, copy, modify, and
* distribute this software and its documentation for any purpose and
* without fee is hereby granted, provided that the above copyright
* notice appear in all copies and that both that copyright notice and
* this permission notice appear in supporting documentation, and that
* the name of M.I.T. not be used in advertising or publicity pertaining
* to distribution of the software without specific, written prior
* permission. Furthermore if you modify this software you must label
* your software as modified software and not distribute it in such a
* fashion that it might be confused with the original M.I.T. software.
* M.I.T. makes no representations about the suitability of
* this software for any purpose. It is provided "as is" without express
* or implied warranty.
*/
#ifndef KIM_TYPES_H
#define KIM_TYPES_H
#include <stdint.h>
#ifdef __cplusplus
extern "C" {
#endif
/*!
* \defgroup kim_types_reference KIM Types and Constants
* @{
*/
/*!
* The KIM Error type.
*/
typedef int32_t kim_error;
/*!
* No error value for the kim_error type.
*/
#define KIM_NO_ERROR ((kim_error) 0)
/*!
* A time value represented in seconds since January 1, 1970.
*/
typedef int64_t kim_time;
/*!
* A duration represented in seconds.
*/
/*!
* An quantity, usually used to return the number of elements in an array.
*/
typedef uint64_t kim_count;
/*!
* A boolean value. 0 means false, all other values mean true.
*/
typedef int kim_boolean;
/*!
* A comparison between two sortable objects.
* \li Less than 0 means the first object is less than the second.
* \li 0 means the two objects are identical.
* \li Greater than 0 means the first object is greater than the second.
* \note Convenience macros are provided for interpreting #kim_comparison
* values to improve code readability.
* See #kim_comparison_is_less_than(), #kim_comparison_is_equal_to() and
* #kim_comparison_is_greater_than()
*/
typedef int kim_comparison;
/*!
* Convenience macro for interpreting #kim_comparison.
*/
#define kim_comparison_is_less_than(c) (c < 0)
/*!
* Convenience macro for interpreting #kim_comparison.
*/
#define kim_comparison_is_equal_to(c) (c == 0)
/*!
* Convenience macro for interpreting #kim_comparison.
*/
#define kim_comparison_is_greater_than(c) (c > 0)
/*!
*/
typedef const char *kim_string;
struct kim_identity_opaque;
/*!
*/
typedef struct kim_identity_opaque *kim_identity;
struct kim_options_opaque;
/*!
*/
typedef struct kim_options_opaque *kim_options;
struct kim_selection_hints_opaque;
/*!
* A KIM Selection Hints object. See \ref kim_selection_hints_overview for more information.
*/
typedef struct kim_selection_hints_opaque *kim_selection_hints;
struct kim_preferences_opaque;
/*!
*/
typedef struct kim_preferences_opaque *kim_preferences;
struct kim_ccache_iterator_opaque;
/*!
* A KIM CCache Iterator object. See \ref kim_credential_cache_collection for more information.
*/
typedef struct kim_ccache_iterator_opaque *kim_ccache_iterator;
struct kim_ccache_opaque;
/*!
*/
typedef struct kim_ccache_opaque *kim_ccache;
struct kim_credential_iterator_opaque;
/*!
* A KIM Credential Iterator object. See \ref kim_credential_iterator for more information.
*/
typedef struct kim_credential_iterator_opaque *kim_credential_iterator;
struct kim_credential_opaque;
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https://simons.berkeley.edu/talks/victoria-kostina-5-1-18 | Talks
Spring 2018
# Exact Minimum Number of Bits to Stabilize a Linear System
Tuesday, May 1st, 2018 3:10 pm3:50 pm
We consider an unstable scalar linear stochastic system, $X_{n+1}=a X_n + Z_n - U_n$, where $a \geq 1$ is the system gain, $Z_n$'s are random variables with bounded $\alpha$-th moments, and $U_n$'s are the control actions that are chosen by a controller who receives a single element of a finite set $\{1, \ldots, M\}$ as its only information about system state $X_i$. We show that $M = \lfloor a + 1 \rfloor$ is necessary and sufficient for $\beta$-moment stability, for any $\beta < \alpha$. The converse is shown using information-theoretic techniques. The matching achievability scheme is a uniform quantizer of zoom-in / zoom-out type whose performance is analyzed using probabilistic arguments. | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.9131394624710083, "perplexity": 728.4745533047202}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2019-18/segments/1555578529606.64/warc/CC-MAIN-20190420100901-20190420122901-00392.warc.gz"} |
https://proceedings.neurips.cc/paper/2017/hash/4da04049a062f5adfe81b67dd755cecc-Abstract.html | Michael Habeck
#### Abstract
<p>The marginal likelihood, or model evidence, is a key quantity in Bayesian parameter estimation and model comparison. For many probabilistic models, computation of the marginal likelihood is challenging, because it involves a sum or integral over an enormous parameter space. Markov chain Monte Carlo (MCMC) is a powerful approach to compute marginal likelihoods. Various MCMC algorithms and evidence estimators have been proposed in the literature. Here we discuss the use of nonequilibrium techniques for estimating the marginal likelihood. Nonequilibrium estimators build on recent developments in statistical physics and are known as annealed importance sampling (AIS) and reverse AIS in probabilistic machine learning. We introduce estimators for the model evidence that combine forward and backward simulations and show for various challenging models that the evidence estimators outperform forward and reverse AIS.</p> | {"extraction_info": {"found_math": false, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.9755285978317261, "perplexity": 698.9020276624898}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2020-50/segments/1606141723602.80/warc/CC-MAIN-20201203062440-20201203092440-00056.warc.gz"} |
https://arxiv.org/abs/math/0607250 | math
# Title:Properties of generalized univariate hypergeometric functions
Abstract: Based on Spiridonov's analysis of elliptic generalizations of the Gauss hypergeometric function, we develop a common framework for 7-parameter families of generalized elliptic, hyperbolic and trigonometric univariate hypergeometric functions. In each case we derive the symmetries of the generalized hypergeometric function under the Weyl group of type E_7 (elliptic, hyperbolic) and of type E_6 (trigonometric) using the appropriate versions of the Nassrallah-Rahman beta integral, and we derive contiguous relations using fundamental addition formulas for theta and sine functions. The top level degenerations of the hyperbolic and trigonometric hypergeometric functions are identified with Ruijsenaars' relativistic hypergeometric function and the Askey-Wilson function, respectively. We show that the degeneration process yields various new and known identities for hyperbolic and trigonometric special functions. We also describe an intimate connection between the hyperbolic and trigonometric theory, which yields an expression of the hyperbolic hypergeometric function as an explicit bilinear sum in trigonometric hypergeometric functions.
Comments: 46 pages Subjects: Classical Analysis and ODEs (math.CA) DOI: 10.1007/s00220-007-0289-0 Cite as: arXiv:math/0607250 [math.CA] (or arXiv:math/0607250v1 [math.CA] for this version)
## Submission history
From: Jasper V. Stokman [view email]
[v1] Tue, 11 Jul 2006 07:50:46 UTC (50 KB) | {"extraction_info": {"found_math": false, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.9388773441314697, "perplexity": 1635.8262383038143}, "config": {"markdown_headings": true, "markdown_code": false, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2019-22/segments/1558232255562.23/warc/CC-MAIN-20190520041753-20190520063753-00171.warc.gz"} |
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# Calling UCLA Fall 2009 Applicants
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Calling UCLA Fall 2009 Applicants [#permalink]
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02 Jun 2008, 14:07
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All, I am planning to apply to Anderson this Fall and wanted to start a thread for everyone else out there with the same idea. I actually just got back from a visit last Thursday and had a fantastic time. I will post more in a follow up later on.
I hope with some help from everyone here we can have the best year for Anderson admits yet, and certainly better than the non-GMAT Club admit rate of 11%.
UCLA Total Stats:
Applicants:
Round 1
Submitted = 16
11 Interview Invites - 73.3%
Waitlists = 5
5 Unknown
nomsg7111 - Waitlisted 1/8 Withdrew for Ross
prospect - Waitlisted 1/8
rjacobs - Waitlisted 1/8
devansh_god - Waitlisted 1/8
Mim3 - Waitlisted 1/8
Unknown Still:
jb32 - Submitted 10/5
tarmac - Submitted 10/8
nutty2010 - Submitted 10/8, Interview Invite 10/16
tritium6 - Submitted 10/?
svarma0305 - Submitted 10/?
Round 1
Submitted = ??
Last edited by jb32 on 02 Jun 2008, 14:37, edited 1 time in total.
Joined: 31 Dec 1969
Location: Russian Federation
Concentration: Entrepreneurship, Technology
GMAT 1: 710 Q49 V0
GMAT 2: 700 Q V
GMAT 3: 740 Q40 V50
GMAT 4: 700 Q48 V38
GMAT 5: 710 Q45 V41
GMAT 6: 680 Q47 V36
GMAT 7: Q42 V44
GMAT 8: Q42 V44
GMAT 9: 740 Q49 V42
GMAT 10: 740 Q V
GMAT 11: 500 Q47 V33
GMAT 12: 670 Q V
GPA: 3.3
WE: Engineering (Manufacturing)
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Re: Calling UCLA Fall 2009 Applicants [#permalink]
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03 Feb 2009, 12:41
2
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Here is some fellowship information from the UCLA adcom:
For those who were not yet awarded a merit fellowship (i.e.
scholarship), please note that we make awards on a rolling basis
throughout the admissions season, depending on who else has been
admitted and who accepts our offers. We will let you know directly
if you get selected for a fellowship at any point.
We generally offer merit fellowships to the top third or so of the
incoming class, based on the overall strength of the applications in
contribution to the school, etc. Such students come here and enhance
the experience of us all.
Other sources of funding do exist, and we will keep admits updated on
developments in the outside private loan market. The team in the
Financial Aid office has more details, and you can learn more from
them after visiting their website at:
http://www.anderson.ucla.edu/x2938.xml
Also, second-year fellowships are awarded based on contributions in
and out of the classroom during the first year. There are some
research- and teaching-assistantships which second-year students
often use to supplement their funding too. These positions are filled
by the professors after they have the chance to get to know the first-
year students on campus.
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Re: Calling UCLA Fall 2009 Applicants [#permalink]
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09 Oct 2008, 10:45
1
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Travel09 wrote:
jb32 wrote:
Well, it's the optional essay and I have to essentially explain two failing grades in two seperate semesters. I used 132 words for the first grade and then 157 for the second and 38 to wrap it up = 327 total. The problem is that I have actual reasons around my grades that I need to explain.
I attended an info session at UCLA last week and adcom mentioned that exceeding the word limit by around 10% is fine. I'm not sure if she was joking when she mentioned that it's better to go over the word limit then to be under the limit by even few words.
So, exceeding the word count by 10% is fine for sure? Is this the total word count across all essays, or you can exceed by 10% each one?
I'll shoot for R2. I'm glad I won't be competing against you guys
Travel09 wrote:
BTW: Anybody from San Diego here?
Yes.
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Re: Calling UCLA Fall 2009 Applicants [#permalink]
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02 Dec 2008, 08:49
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Hello folks! I visited the UCLA Fully Employed MBA (FEMBA) info session yesterday. I must say i am very impressed by a few things: 1) All courses are taught by the SAME professors that teach the full time courses. I know this is not always the case with other part time MBA programs. Even HASS has adjuncts and part time professors teach their Weekend and Evening MBA courses. 2) UCLA offers schedule options, including all day Saturday, weeknights, and combination of a weeknight and Saturday morning. 3) The cost is reasonable ($30k per year for 3 years), especially if your employer will foot part of the bill. 4) As an alum you can take electives for life without paying the course fee (you must pay for books and parking); I think this is a wonderful idea....especially for a nerd like me! 5) Their global access program, its kind of like a thesis one has to do in a group, sounds great.....very practical. 6) They offer half courses in intensive week long, 3 hr a day, sessions. Just thought I share this. Senior Manager Joined: 24 Feb 2008 Posts: 348 Schools: UCSD ($) , UCLA, USC (\$), Stanford
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Re: Calling UCLA Fall 2009 Applicants [#permalink]
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26 Mar 2009, 09:16
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Waitlisted. Yawn....
As usual, the UCLA brilliant strategy and forseeing to improve yield seems to have led to admitting just a few people who are already committed elsewhere or do not have UCLA as their #1 choice, and waitlist a bigger portion.
On the other hand, it was my top choice and had I gotten admitted I probably would've committed quickly, but with this wl, not any more..
Congrats to the admits! I hope you don't waste it. My rant was based mostly on posts read on another forum.
Rjacobs, I seem to be following your steps ...which means next up is a ding from Stanford.
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Re: Calling UCLA Fall 2009 Applicants [#permalink]
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15 Apr 2009, 09:41
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chineseburned wrote:
Withdrew from the WL...this agonizing wait would just not be healthy...and since I'd not go there without a schollie, what's the point to play it nice and potentially waste an admit when someone else might need it desperately?
Good luck chineseburned - didn't know you got money from USC. Congrats!
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Re: Calling UCLA Fall 2009 Applicants [#permalink]
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02 Jun 2008, 14:10
I was about to create this thread today as well. Count me in
By the way, they have a new Director of Admissions who started mid way through the 2008 application season. I really wonder how this will affect selectivity, as well as the essay questions this year.
UCLA's essay questions have historically remained very similar over the years. Additionally, I believe UCLA has historically had a higher admit rate in R2 than in R1 - which is sort of backwards. This may change.
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Re: Calling UCLA Fall 2009 Applicants [#permalink]
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02 Jun 2008, 14:36
I'm not sure how this will change as I was not allowed to meet with anyone for a '1-on-1 counseling session' while I was there. She's from Wharton, so I am hoping the overall feel of the office will be more friendly and helpful.
My real questions are in regards to the expected changes in the curriculum for 2009. From the website, it looks like the following will be under evaluation "...pre-skilling, orientation, timing, sequence, number and content of core courses, start date of the quarter, and other developmental experiences that might add to the learning foundation of the MBA."
This could lead to some big changes, as one of the things I'm not crazy about is the October start date for classes. Anderson students start recruiting later than all of the other schools and then finish classes later than everyone else. One student told me he had to take a final during his internship because classes do not finish until the middle of June. Not the best thing if you are joining a formal internship program at a major bank or consulting firm.
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Re: Calling UCLA Fall 2009 Applicants [#permalink]
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02 Jun 2008, 17:07
Good to see you guys being proactive. I will also be applying to Anderson in the fall. I tried to visit last April, but the admissions office was less than helpful (in late March, they informed me that they hadn't finalized their class visit schedules yet...). I'll be making a return trip in October (hopefully when I'm being interviewed early for USC-Marshall, hehe).
I'm going to entertainment marketing/consulting, so there's really no better place than LA.
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Re: Calling UCLA Fall 2009 Applicants [#permalink]
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02 Jun 2008, 20:24
I'm seriously considering applying to UCLA. I just moved to Southern California, hopefully I will be able to do a school visit once classes start.
BTW: Anybody from San Diego here?
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Re: Calling UCLA Fall 2009 Applicants [#permalink]
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03 Jun 2008, 06:57
Hey guys,
Count me in too. I'll be applying in fall 09.
Good to have this thread up and running. I was thinking of starting the same for the last 3 days, but held back, coz no admission info is available at this point of time.
Best of luck everybody..... May we all land into DBS (Dream Business School )
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Re: Calling UCLA Fall 2009 Applicants [#permalink]
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03 Jun 2008, 12:52
Count me in. I'm a college senior though, so it will be an uphill battle.
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Re: Calling UCLA Fall 2009 Applicants [#permalink]
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04 Jun 2008, 20:04
So I wanted to post my thoughts from my visit to UCLA last week. It was a great visit overall and UCLA is definitely near the top of my list.
I stayed with my girlfriends parents out in Temecula which is a 1.5 hour drive to Westwood on a normal day. With traffic on a weekday it is over 3 hours and bumper to bumper a large part of the way. Needless to say even leaving at 6:45 am, I was about a minute late to my Business Strategy class. Overall, the class was wonderful. We started off discussing a case about Walt Disney and basically the question was what would you divest if the year was 2000? Of course the groups were not allowed to use events that had transpired since then and it was great to hear groups justify their decisions. One of the students had worked as an Imagineer at Disney and could provide some great insights on the management style of one of the executives we discussed in class. I was really impressed at that point.
After class I had a meeting that I had pre-arranged with a student from the Finance Club. I gained some valuable insights on the Finance program at Anderson as well as some information about investment banking recruiting. Basically there are some great professors at Anderson, maybe not as many as at Wharton or Chicago, but some are really top of their field. Only about 45-60 students really want to do I-Banking each year out of 350 or so in the program, so the competition is a little less than other M7 schools. All of the major banks come to campus, roughly about 18-20 each year. They mostly recruit for the LA, SF, and NYC offices. Two things that I learned: first, GMAT matters only if it is below 700, otherwise it doesn't and two, UG GPA really only matters to top banks like Goldman and Lehman. If you have a strong MBA GPA in your first year, then UG GPA probably won't matter as much.
The Finance Club does a tremendous amount for students, including: arranging trips to NY and SF, interview prep by 2nd years, case study presentations by banks, and modeling workshops. Pretty standard at most top finance schools, but I was cool to see they offer their memebers a lot of services.
Another cool thing about UCLA is they allow you to take classes outside Anderson, including Law classes. One class that was offered last year as an elective was a 'Deal' class offered in partnership with the law school. All the class did was analyze past deals with the actual deal bankers and lawyers presenting the material. I thought this was really, really cool.
After lunch, I visited a 1st year core class, Managing & Leading Organizations. The professor really kept the class interesting during the lecture portion of the class. During my visit they discussed negotiation techniques, which I really enjoyed learning. I was impressed how Anderson teaches soft skills such as leadership and negotiation during the core classes. These are really valuable skills for luse ater in life. The professor left me with one piece of wisdom that I will share with you: "Never learn the cynical lesson when the outcome is not in your favor". I thought this was a great lesson for b-school applicants. Even if you don't get in this year, learn where you went wrong and come back stronger next year.
Overall, I thought Anderson was amazing. The facilities were top notch and overall UCLA is a beautiful campus!! I like how the business school is right on campus and doesn't feel isolated like at some other schools I have visited. The students seemed really bright and engaging. Several were tremendously helpful, although the admissions office lived up to its prior reputation. I went in to ask to speak with someone about the new curriculum changes the administration is currently discussing. I was politely told I could not have a 1-on-1 counseling session and was handed the UCLA guidebook instead. The student who helped me obviously had no idea about the new changes.
One final negative I heard from students was the start and end date of classes. Most b-schools start at the beginning of September and recruiting starts almost immediately, while Anderson starts in the beginning of October. This is a slight disadvantage in recruiting, although not that big of a deal. Most students at other schools have already had a full semester of classes by the time 1st year interviews start and students at Anderson have only had fall quarter. Also, Anderson ends classes in the middle of June, when most formal internship programs are already under way.
Hope this helps anyone thinking of applying. Let me know if I can answer any questions about Anderson (as if I'm some kind of expert ) or my provide any additional information about my experience.
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Re: Calling UCLA Fall 2009 Applicants [#permalink]
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04 Jun 2008, 20:23
jb32 wrote:
So I wanted to post my thoughts from my visit to UCLA last week. It was a great visit overall and UCLA is definitely near the top of my list.
I stayed with my girlfriends parents out in Temecula which is a 1.5 hour drive to Westwood on a normal day. With traffic on a weekday it is over 3 hours and bumper to bumper a large part of the way. Needless to say even leaving at 6:45 am, I was about a minute late to my Business Strategy class. Overall, the class was wonderful. We started off discussing a case about Walt Disney and basically the question was what would you divest if the year was 2000? Of course the groups were not allowed to use events that had transpired since then and it was great to hear groups justify their decisions. One of the students had worked as an Imagineer at Disney and could provide some great insights on the management style of one of the executives we discussed in class. I was really impressed at that point.
After class I had a meeting that I had pre-arranged with a student from the Finance Club. I gained some valuable insights on the Finance program at Anderson as well as some information about investment banking recruiting. Basically there are some great professors at Anderson, maybe not as many as at Wharton or Chicago, but some are really top of their field. Only about 45-60 students really want to do I-Banking each year out of 350 or so in the program, so the competition is a little less than other M7 schools. All of the major banks come to campus, roughly about 18-20 each year. They mostly recruit for the LA, SF, and NYC offices. Two things that I learned: first, GMAT matters only if it is below 700, otherwise it doesn't and two, UG GPA really only matters to top banks like Goldman and Lehman. If you have a strong MBA GPA in your first year, then UG GPA probably won't matter as much.
The Finance Club does a tremendous amount for students, including: arranging trips to NY and SF, interview prep by 2nd years, case study presentations by banks, and modeling workshops. Pretty standard at most top finance schools, but I was cool to see they offer their memebers a lot of services.
Another cool thing about UCLA is they allow you to take classes outside Anderson, including Law classes. One class that was offered last year as an elective was a 'Deal' class offered in partnership with the law school. All the class did was analyze past deals with the actual deal bankers and lawyers presenting the material. I thought this was really, really cool.
After lunch, I visited a 1st year core class, Managing & Leading Organizations. The professor really kept the class interesting during the lecture portion of the class. During my visit they discussed negotiation techniques, which I really enjoyed learning. I was impressed how Anderson teaches soft skills such as leadership and negotiation during the core classes. These are really valuable skills for luse ater in life. The professor left me with one piece of wisdom that I will share with you: "Never learn the cynical lesson when the outcome is not in your favor". I thought this was a great lesson for b-school applicants. Even if you don't get in this year, learn where you went wrong and come back stronger next year.
Overall, I thought Anderson was amazing. The facilities were top notch and overall UCLA is a beautiful campus!! I like how the business school is right on campus and doesn't feel isolated like at some other schools I have visited. The students seemed really bright and engaging. Several were tremendously helpful, although the admissions office lived up to its prior reputation. I went in to ask to speak with someone about the new curriculum changes the administration is currently discussing. I was politely told I could not have a 1-on-1 counseling session and was handed the UCLA guidebook instead. The student who helped me obviously had no idea about the new changes.
One final negative I heard from students was the start and end date of classes. Most b-schools start at the beginning of September and recruiting starts almost immediately, while Anderson starts in the beginning of October. This is a slight disadvantage in recruiting, although not that big of a deal. Most students at other schools have already had a full semester of classes by the time 1st year interviews start and students at Anderson have only had fall quarter. Also, Anderson ends classes in the middle of June, when most formal internship programs are already under way.
Hope this helps anyone thinking of applying. Let me know if I can answer any questions about Anderson (as if I'm some kind of expert ) or my provide any additional information about my experience.
I'm located in LA so I have visited a couple of times. I have similar thoughts to you. The school seems to be a gem for Finance/Investment Banking recruiting on the West Coast, and there are not very many students interested in it, so the competition is slim. The faculty and the facilities are both top notch - and it feels like a private school at a public school price. Unlike Columbia and Chicago, which are located in average at best neighborhoods in NYC/Chicago, Anderson is located smack dab in the best part of LA. There are internship opportunities abound within literally a 5 mile radius and the Westside is also the most happening area for 20/30 something young professionals.
One last thing to consider is that private equity/venture capital firms are plentiful on the West Coast and they are a major backbone of the entrepeneurial economy here. It seems very possible to break into a smaller PE/VC firm in Southern California out of Anderson - as it's the highest ranked school in SoCal. It is a step below Stanford for California PE/VC, but I would consider it to be on the same level as Haas.
I'll admit that one big weakness I see in Anderson is consulting recruiting. MBB seem to prefer Haas grads over Anderson, and a lot of the Anderson people interested in consulting seem to end up at 2nd tier firms. I have no interest in consulting - so this won't affect me in the slightest.
In general, I don't think you can go wrong with being a financier on the West Coast. Just looking at simple supply and demand - top investment bankers and financiers are almost a commodity in NYC. There are far fewer of them in California, and the booming economy here still warrants and will continue to warrant a lot of demand for their services.
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Re: Calling UCLA Fall 2009 Applicants [#permalink]
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04 Jun 2008, 20:50
terp06 wrote:
I'm located in LA so I have visited a couple of times. I have similar thoughts to you. The school seems to be a gem for Finance/Investment Banking recruiting on the West Coast, and there are not very many students interested in it, so the competition is slim. The faculty and the facilities are both top notch - and it feels like a private school at a public school price. Unlike Columbia and Chicago, which are located in average at best neighborhoods in NYC/Chicago, Anderson is located smack dab in the best part of LA. There are internship opportunities abound within literally a 5 mile radius and the Westside is also the most happening area for 20/30 something young professionals.
One last thing to consider is that private equity/venture capital firms are plentiful on the West Coast and they are a major backbone of the entrepeneurial economy here. It seems very possible to break into a smaller PE/VC firm in Southern California out of Anderson - as it's the highest ranked school in SoCal. It is a step below Stanford for California PE/VC, but I would consider it to be on the same level as Haas.
In general, I don't think you can go wrong with being a financier on the West Coast. Just looking at simple supply and demand - top investment bankers and financiers are almost a commodity in NYC. There are far fewer of them in California, and the booming economy here still warrants and will continue to warrant a lot of demand for their services.
I completely agree that the location is absolutely top-notch. I love Westwood and the West L.A. area. I think something can be said for being a financier on the West Coast, especially in Southern California. There are plenty of small PE/VC firms that might be willing to hire an Anderson MBA. It could be a great opportunity, but I really don't want to go that route just yet. I really want to go into banking and while I may do recruiting for a VC/PE, I think I have a lot to learn before I can make a real contribution to a VC/PE firm. One day after 3-5 years at a bulge bracket would be ideal for me.
One other concern of mine is the brand recognition of Anderson on the East Coast. I know Wharton, Chicago, Columbia, etc. have a better brand across the country than UCLA. If I want to stay on the West Coast, then UCLA is great, but if I want to go to NYC, then the brand isn't quite as strong. I'm not sure how this will ultimately play into my decision as one of my dreams has always been to work on Wall Street. Maybe not right out of b-school, but sometime down the road.
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Re: Calling UCLA Fall 2009 Applicants [#permalink]
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04 Jun 2008, 21:26
jb32 wrote:
terp06 wrote:
I'm located in LA so I have visited a couple of times. I have similar thoughts to you. The school seems to be a gem for Finance/Investment Banking recruiting on the West Coast, and there are not very many students interested in it, so the competition is slim. The faculty and the facilities are both top notch - and it feels like a private school at a public school price. Unlike Columbia and Chicago, which are located in average at best neighborhoods in NYC/Chicago, Anderson is located smack dab in the best part of LA. There are internship opportunities abound within literally a 5 mile radius and the Westside is also the most happening area for 20/30 something young professionals.
One last thing to consider is that private equity/venture capital firms are plentiful on the West Coast and they are a major backbone of the entrepeneurial economy here. It seems very possible to break into a smaller PE/VC firm in Southern California out of Anderson - as it's the highest ranked school in SoCal. It is a step below Stanford for California PE/VC, but I would consider it to be on the same level as Haas.
In general, I don't think you can go wrong with being a financier on the West Coast. Just looking at simple supply and demand - top investment bankers and financiers are almost a commodity in NYC. There are far fewer of them in California, and the booming economy here still warrants and will continue to warrant a lot of demand for their services.
I completely agree that the location is absolutely top-notch. I love Westwood and the West L.A. area. I think something can be said for being a financier on the West Coast, especially in Southern California. There are plenty of small PE/VC firms that might be willing to hire an Anderson MBA. It could be a great opportunity, but I really don't want to go that route just yet. I really want to go into banking and while I may do recruiting for a VC/PE, I think I have a lot to learn before I can make a real contribution to a VC/PE firm. One day after 3-5 years at a bulge bracket would be ideal for me.
One other concern of mine is the brand recognition of Anderson on the East Coast. I know Wharton, Chicago, Columbia, etc. have a better brand across the country than UCLA. If I want to stay on the West Coast, then UCLA is great, but if I want to go to NYC, then the brand isn't quite as strong. I'm not sure how this will ultimately play into my decision as one of my dreams has always been to work on Wall Street. Maybe not right out of b-school, but sometime down the road.
I'm having trouble making the same decision that you are - i.e. should I go into banking first for a few years. It'll be something to think about and worry about in a years time I guess
As far as NYC placement - if you want to be a banker in NYC, you will have that opportunity from Anderson. Several students at Anderson told me that the BBs have far more demand than availability for spots in the West Coast offices. Once everyone comes to Anderson, they mostly want to stay in California. If you want to go to NYC, they will gladly accomodate you and place you out in NYC. NYC banking jobs are a dime a dozen compared to the relatively few number of spots in the California offices. You are correct that the brand is not as strong, and the Ivy League network dominates Wall Street and NYC, but you will certainly have the opportunity to recruit for NYC jobs and be placed there out of school if that is your desire.
Several experienced bankers say that if you want to make a career in investment banking at a bulge bracket, you would be wise to spend a few years in New York City and build your network/connections there before moving to a regional office. The main decision makers are in NYC, and it is good for them to know you well. Personally, if I attended Anderson, I would take this with a grain of salt as I don't think I'm cut out to be a career banker - I think it's just a great training ground for any finance career.
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Re: Calling UCLA Fall 2009 Applicants [#permalink]
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06 Jun 2008, 12:52
Thanks for posting your UCLA visit recap! Lots of good information there.
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Re: Calling UCLA Fall 2009 Applicants [#permalink]
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06 Jun 2008, 13:01
I went to UCLA undergrad and plan on applying for bschool. My time at UCLA weret the best years of my life (I was born and raised on the westside of LA), and I would not mind living in the Westwood bubble for another 2 years. I was actually supposed to go to the diversity workshop that they held last year, but I couldn't make it, so I can't quite speak of class/professor quaity. All I can comment on are the secondary aspects associated with the school. One thing to keep in mind...despite what everyone may tell you, if you go to UCLA, you don't need a car if you live in Westwood village. And if you do bring a car, be prepared to pay high parking fees, get numerous parking tickets, not find parking at all, or get a campus parking pass to a lot that is on the other side of the school (campus is huge). There is a good bus line that will take you directly to Santa Monica/Venice (beach, 3rd st promenade, venice boardwalk etc), and when it comes to partying on the weekends (there are only two bars in the village), you either stay local, take a cab, or get a friend to drive. Everything else you might need, groceries, movie theatre, restaurants, coffee, movie rentals, clothes...even electronics to furniture can be found within walking distance. Just something for you out of staters to keep in mind.
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06 Jun 2008, 19:26
From what I've been seeing, the Anderson network in San Francisco's investment banking community is really something to be reckoned with. I think you'll find just as many Anderson grads in SF I-Banking as you will M7 grads.
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Re: Calling UCLA Fall 2009 Applicants [#permalink]
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06 Jun 2008, 22:27
terp06 wrote:
From what I've been seeing, the Anderson network in San Francisco's investment banking community is really something to be reckoned with. I think you'll find just as many Anderson grads in SF I-Banking as you will M7 grads.
I hear you, but as a career-switcher to banking I'm a little concerned about going to SF. I've been talking to several people about the value of the network you develop starting out in NY. I think if you went to a mid-tier like JMP or Thomas Weisel that is based in SF you'd be fine, but I'm wondering how great an advantage you would have at Goldman or Morgan Stanley being in NY over SF.
I love Anderson and would be very happy to get an acceptance there this fall, but after thinking about it a little deeper, I see why a lot of people have UCLA as a backup to the other top finance schools. It's not a knock against Anderson per se, but more a result of their alumni's geographic concentration on the West Coast. The brand just isn't as strong nationally and that is a fact. People always talk about the best school by ranking, but I think it's really more about the best brand. What school has that certain Je-ne-sais-quoi? What school makes everyone else on this board jealous when you get an admittance? That is the power of the brand.
Re: Calling UCLA Fall 2009 Applicants [#permalink] 06 Jun 2008, 22:27
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https://www.studyadda.com/sample-papers/neet-sample-test-paper-51_q29/644/351119 | • # question_answer 29) A sphere and a cube of same material and same volume are heated upto the same temperature and allowed to cool in the same surroundings. The ratio of the amounts of radiations emitted will be- A) $1\,\,:\,\,1$ B) $\frac{4\pi }{3}\,\,:\,\,1$C) ${{\left( \frac{\pi }{6} \right)}^{1/3}}\,:\,\,1\,$ D) $\frac{1}{2}{{\left( \frac{4\pi }{3} \right)}^{2/3}}\,:\,\,1\,$
${{V}_{1}}={{V}_{2}}$ $\frac{4}{3}\pi {{r}^{3}}\,\,=\,\,{{\ell }^{3}}$ $r={{\left( \frac{3}{4\pi } \right)}^{1/3}}\,\,\ell \Rightarrow {{r}^{2}}\,\,=\,\,{{\left( \frac{3}{4\pi } \right)}^{2/3}}{{\ell }^{2}}$ $\frac{dQ}{dt}\,\,\,\propto \,\,A$ $\Rightarrow \,\,\frac{{{R}_{{{h}_{1}}}}}{{{R}_{{{h}_{2}}}}}\,=\,\frac{4\pi {{r}^{2}}}{6{{t}^{2}}}$ $=\frac{4\pi }{6}\,{{\left( \frac{3}{4\pi } \right)}^{2/3}}\,\,=\,\,\frac{1}{2}\left( \frac{4\pi }{3} \right){{\,}^{1/3}}:1$ | {"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.9175395965576172, "perplexity": 965.8525989603684}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2019-30/segments/1563195524522.18/warc/CC-MAIN-20190716095720-20190716121720-00492.warc.gz"} |