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https://en.wikipedia.org/wiki/Steinberg%20formula | In mathematical representation theory, Steinberg's formula, introduced by , describes the multiplicity of an irreducible representation of a semisimple complex Lie algebra in a tensor product of two irreducible representations.
It is a consequence of the Weyl character formula, and for the Lie algebra sl2 it is essentially the Clebsch–Gordan formula.
Steinberg's formula states that the multiplicity of the irreducible representation of highest weight ν in the tensor product of the irreducible representations with highest weights λ and μ is given by
where W is the Weyl group, ε is the determinant of an element of the Weyl group, ρ is the Weyl vector, and P is the Kostant partition function giving the number of ways of writing a vector as a sum of positive roots. |
https://en.wikipedia.org/wiki/RNF114 | E3 ubiquitin-protein ligase RNF114 is a protein that in humans is encoded by the RNF114 gene. |
https://en.wikipedia.org/wiki/IBM%20Watson | IBM Watson is a question-answering computer system capable of answering questions posed in natural language, developed in IBM's DeepQA project by a research team led by principal investigator David Ferrucci. Watson was named after IBM's founder and first CEO, industrialist Thomas J. Watson.
The computer system was initially developed to answer questions on the quiz show Jeopardy! and in 2011, the Watson computer system competed on Jeopardy! against champions Brad Rutter and Ken Jennings, winning the first place prize of 1 million USD.
In February 2013, IBM announced that Watson's first commercial application would be for utilization management decisions in lung cancer treatment at Memorial Sloan Kettering Cancer Center, New York City, in conjunction with WellPoint (now Elevance Health)..
Description
Watson was created as a question answering (QA) computing system that IBM built to apply advanced natural language processing, information retrieval, knowledge representation, automated reasoning, and machine learning technologies to the field of open domain question answering.
IBM stated that Watson uses "more than 100 different techniques to analyze natural language, identify sources, find and generate hypotheses, find and score evidence, and merge and rank hypotheses."
In recent years, Watson's capabilities have been extended and the way in which Watson works has been changed to take advantage of new deployment models (Watson on IBM Cloud), evolved machine learning capabilities, and optimized hardware available to developers and researchers. It is no longer purely a question answering (QA) computing system designed from Q&A pairs but can now 'see', 'hear', 'read', 'talk', 'taste', 'interpret', 'learn' and 'recommend'.
Software
Watson uses IBM's DeepQA software and the Apache UIMA (Unstructured Information Management Architecture) framework implementation. The system was written in various languages, including Java, C++, and Prolog, and runs on the SUSE Linux En |
https://en.wikipedia.org/wiki/FLOSS%20Manuals | The FLOSS Manuals (FM) is a non-profit foundation founded in 2006 by Adam Hyde and based in the Netherlands. The foundation is focused on the creation of quality documentation about how to use free software.
Its web site is a wiki (previously using the TWiki and Booki programs, now using Booktype) focused on the collaborative authoring of manuals. The documentation is licensed under the GPL. Although initially the manuals were covered by the GFDL, the material was relicensed to the GPL due to concerns about the limitations of the GFDL.
Anyone can contribute to the material at FLOSS Manuals. Each manual has a maintainer – very much like the Debian maintainer system. The maintainer keeps an overview of the manual and discusses with those interested the structure, etc. The maintainer is also responsible for gathering new contributors together. Not all edits are 'live' – the edits are published to the manual when ready. This is to ensure the quality of the manuals is as high and as reliable as possible and that no new user encounters 'half finished' content.
Manuals are available as HTML online, or indexed PDF. Additionally manuals can be remixed so anyone can create their own manual and export to indexed PDF, HTML (ZIP/tar) or an 'Ajax' include.
In fall 2007, Floss manuals was awarded a 15,000 Euro prize by the Dutch Digital Pioneer fund. It has also been financially supported by Google and NLnet. FLOSS Manuals also received a Transmediale Award for its work on Booki and has also been featured in the Texas Linux Fest 2010.
List of manuals
FLOSS Manuals has manuals for all of the following.
Popularity
Some manuals have been selected for inclusion on the VALO-CD, a collection of the best software for Windows. |
https://en.wikipedia.org/wiki/Acoustic%20angiography | A specific branch of contrast-enhanced ultrasound, acoustic angiography is a minimally invasive and non-ionizing medical imaging technique used to visualize vasculature. Acoustic angiography was first developed by the Dayton Laboratory at North Carolina State University and provides a safe, portable, and inexpensive alternative to the most common methods of angiography such as Magnetic Resonance Angiography and Computed Tomography Angiography. Although ultrasound does not traditionally exhibit the high resolution of MRI or CT, high-frequency ultrasound (HFU) achieves relatively high resolution by sacrificing some penetration depth. HFU typically uses waves between 20 and 100 MHz and achieves resolution of 16-80μm at depths of 3-12mm. Although HFU has exhibited adequate resolution to monitor things like tumor growth in the skin layers, on its own it lacks the depth and contrast necessary for imaging blood vessels. Acoustic angiography overcomes the weaknesses of HFU by combining contrast-enhanced ultrasound with the use of a dual-element ultrasound transducer to achieve high resolution visualization of blood vessels at relatively deep penetration levels.
Acoustic angiography is performed by first injecting specially designed microbubbles with a low resonant frequency into the vessels. Next, a low-frequency transducer element with good depth penetration is used to send ultrasound waves into the sample at the resonant frequency of the microbubbles. This will generate a response from the microbubbles consisting of subharmonic, fundamental, and super-harmonic frequencies, as well as a response from the surrounding tissue consisting of only the fundamental and second-harmonic frequencies. Finally, a high-frequency transducer with high resolution is used to measure the super-harmonic frequencies, effectively removing any background signal from the microbubble signal, and allowing the vessels to be visualized
Background
Angiography, or the examination of blood vessels, i |
https://en.wikipedia.org/wiki/File%20synchronization | File synchronization (or syncing) in computing is the process of ensuring that computer files in two or more locations are updated via certain rules.
In one-way file synchronization, also called mirroring, updated files are copied from a source location to one or more target locations, but no files are copied back to the source location. In two-way file synchronization, updated files are copied in both directions, usually with the purpose of keeping the two locations identical to each other. In this article, the term synchronization refers exclusively to two-way file synchronization.
File synchronization is commonly used for home backups on external hard drives or updating for transport on USB flash drives. BitTorrent Sync, Dropbox, SKYSITE, Nextcloud, OneDrive, Google Drive and iCloud are prominent products. Some backup software also support real-time file sync. The automatic process prevents copying already identical files and thus can be faster and save much time versus a manual copy, and is less error prone. However this suffers from the limit that the synchronized files must physically fit in the portable storage device. Synchronization software that only keeps a list of files and the changed files eliminates this problem (e.g. the "snapshot" feature in Beyond Compare or the "package" feature in Synchronize It!). It is especially useful for mobile workers, or others that work on multiple computers.
It is possible to synchronize multiple locations by synchronizing them one pair at a time. The Unison Manual describes how to do this:
If you need to do this, the most reliable way to set things up is to organize the machines into a "star topology," with one machine designated as the "hub" and the rest as "spokes," and with each spoke machine synchronizing only with the hub. The big advantage of the star topology is that it eliminates the possibility of confusing "spurious conflicts" arising from the fact that a separate archive is maintained by Unison for every |
https://en.wikipedia.org/wiki/Moldable%20wood | Moldable wood is a strong and flexible cellulose-based material. Moldable wood can be folded into different shapes without breaking or snapping. The patented synthesis is based on the deconstruction and softening of the wood's lignin, then re-swelling the material in a rapid "water-shock" process that produces a wrinkled cell wall structure. The result of this unique structure is a flexible wood material that can be molded or folded, with the final shape locked in plate by simple air-drying. This discovery broadens the potential applications of wood as a sustainable structural material. This research, which was a collaborative effort between the University of Maryland, Yale University, Ohio State University, USDA Forest Service, University of Bristol, University of North Texas, ETH Zurich, and the Center for Materials Innovation, was published on the cover of Science in October 2021. |
https://en.wikipedia.org/wiki/Force%20density | In fluid mechanics, the force density is the negative gradient of pressure. It has the physical dimensions of force per unit volume. Force density is a vector field representing the flux density of the hydrostatic force within the bulk of a fluid. Force density is represented by the symbol f, and given by the following equation, where p is the pressure:
.
The net force on a differential volume element dV of the fluid is:
Force density acts in different ways which is caused by the boundary conditions. There are stick-slip boundary conditions and stick boundary conditions which affect force density.
In a sphere placed in an arbitrary non-stationary flow field of viscous incompressible fluid for stick boundary conditions where the force density's calculations leads to show the generalisation of Faxen's theorem to force multipole moments of arbitrary order.
In a sphere moving in an incompressible fluid in a non-stationary flow with mixed stick-slip boundary condition where the force of density shows an expression of the Faxén type for the total force, but the total torque and the symmetric force-dipole moment.
The force density at a point in a fluid, divided by the density, is the acceleration of the fluid at that point.
The force density f is defined as the force per unit volume, so that the net force can be calculated by:
.
The force density in an electromagnetic field is given in CGS by:
,
where is the charge density, E is the electric field, J is the current density, c is the speed of light, and B is the magnetic field.
See also
Pressure gradient
Gradient |
https://en.wikipedia.org/wiki/Contact%20scraping | In online advertising, contact scraping is the practice of obtaining access to a customer's e-mail account in order to retrieve contact information that is then used for marketing purposes.
The New York Times refers to the practices of Tagged, MyLife and desktopdating.net as "contact scraping".
Several commercial packages are available that implement contact scraping for their customers, including ViralInviter, TrafficXplode, and TheTsunamiEffect.
Contact scraping is one of the applications of web scraping, and the example of email scraping tools include Uipath, Import.io, and Screen Scraper. The alternative web scraping tools include UzunExt, R functions, and Python Beautiful Soup. The legal issues of contact scraping is under the legality of web scraping.
Web scraping tools
Following web scraping tools can be used as alternatives for contact scraping:
UzunExt is an approach of data scraping in which string methods and crawling process are applied to extract information without using a DOM Tree .
R functions data. rm() and data. rm.a() can be used as a web scraping strategy.
Python Beautiful Soup libraries can be used to scrape data and converted data into csv files.
Legal issues
United States
In the United States, there exists three most commonly legal claims related to web scraping: compilation copyright infringement, violation of the Computer Fraud and Abuse Act (CFAA), and electronic trespass to chattel claims. For example, the users of "scraping tools" may violate the electronic trespass to chattel claims. One of the well-known cases is Intel Corp. v. Hamidi, in which the US court decided that the computer context was not included in the common law trespass claims. However, the three legal claims have been changed doctrinally, and it is uncertain whether the claims will still exist in the future. For instance, the applicability of the CFAA has been narrowed due to the technical similarities between web scraping and web browsing. In the case of EF |
https://en.wikipedia.org/wiki/List%20of%20DVD%20authoring%20software | The following applications can be used to create playable DVDs.
Free software
Free software implementations often lack features such as encryption and region coding due to licensing restrictions issues, and depending on the demands of the DVD producer, may not be considered
suitable for mass-market use.
DeVeDe (Linux)
DVD Flick (Windows only)
DVDStyler (Windows, Mac OS X, and Linux using wxWidgets. Recent versions are bundled with Potentially Unwanted Programs that may accidentally be installed unless care is taken during installation.)
Professional studio software
MAGIX Vegas DVD Architect (previously known as Sony Creative Software's DVD Architect Pro) (discontinued)
Apple DVD Studio Pro (Mac) (discontinued)
Sonic DVDit Pro (formerly DVD Producer) (discontinued)
Adobe Encore (EOL / discontinued)
Sonic DVD Creator (discontinued)
Professional corporate software
MAGIX Vegas DVD Architect (previously known as Sony Creative Software's DVD Architect Pro) (discontinued)
Adobe Encore (Last version is CS6, bundled with Adobe Premiere Pro CS6 / EOL) (discontinued)
Sonic Scenarist SD/BD/UHj
MediaChance DVD-lab (discontinued)
Home
Apple iDVD (Mac) (discontinued)
CyberLink Media Suite
Nero Vision
Pinnacle Studio
Roxio Easy Media Creator
Roxio Toast (for Mac OS)
Sonic MyDVD
TMPGEnc DVD Author
Ulead DVD MovieFactory
Windows DVD Maker (discontinued)
WinDVD Creator
Ashampoo Burning Studio
See also
DVD-Video
DVD authoring
DVD ripper |
https://en.wikipedia.org/wiki/Windbelt | The Windbelt is a wind power harvesting device invented by Shawn Frayne in 2004 for converting wind power to electricity. It consists of a flexible polymer ribbon stretched between supports transverse to the wind direction, with magnets glued to it. When the wind blows across it, the ribbon vibrates due to vortex shedding, similar to the action of an aeolian harp. The vibrating movement of the magnets induces current in nearby pickup coils by electromagnetic induction.
One prototype has powered two LEDs, a radio, and a clock (separately) using wind generated from a household fan. The cost of the materials was well under US$10. $2–$5 for 40 mW is a cost of $50–$125 per watt.
There are three sizes in development:
The microBelt, a 12 cm version. This could be put into production in around six months. Its expected to produce 1 milliwatt average. To charge a pair of ideal rechargeable AA cells (2.5Ah 1.2v) this would take 6000 hours, or 250 days.
The Windcell, a 1-metre version that could be used to power meshed WiFi repeaters, charge cellphones, or run LED lights. This could go into production within 18 to 24 months. It is hoped that a square metre panel at 6 m/s average windspeed can generate 10 W average.
An experimental 10-metre model that has no production date.
The Windbelt's inventor, Shawn Frayn, was a winner of the 2007 Breakthrough Award from the publishers of the magazine, Popular Mechanics. He is trying to make the Windbelt cheaper.
The inventor's claims that the device is 10–30 times more efficient than small wind turbines have been refuted by tests. The microWindbelt could generate 0.2 mW at a wind speed of 3.5 m/s and 5 mW at 7.5 m/s, which represent efficiencies (ηCp) of 0.21 and 0.53 respectively. Wind turbines typically have efficiencies of 1% to 10%. Since the Windbelt a number of other "flutter" wind harvester devices have been designed, but like the Windbelt almost all have efficiencies below turbine machines.
Footnotes |
https://en.wikipedia.org/wiki/Succinyl%20coenzyme%20A%20synthetase | Succinyl coenzyme A synthetase (SCS, also known as succinyl-CoA synthetase or succinate thiokinase or succinate-CoA ligase) is an enzyme that catalyzes the reversible reaction of succinyl-CoA to succinate. The enzyme facilitates the coupling of this reaction to the formation of a nucleoside triphosphate molecule (either GTP or ATP) from an inorganic phosphate molecule and a nucleoside diphosphate molecule (either GDP or ADP). It plays a key role as one of the catalysts involved in the citric acid cycle, a central pathway in cellular metabolism, and it is located within the mitochondrial matrix of a cell.
Chemical reaction and enzyme mechanism
Succinyl CoA synthetase catalyzes the following reversible reaction:
Succinyl CoA + Pi + NDP ↔ Succinate + CoA + NTP
where Pi denotes inorganic phosphate, NDP denotes nucleotide diphosphate (either GDP or ADP), and NTP denotes nucleotide triphosphate (either GTP or ATP). As mentioned, the enzyme facilitates coupling of the conversion of succinyl CoA to succinate with the formation of NTP from NDP and Pi. The reaction has a biochemical standard state free energy change of -3.4 kJ/mol. The reaction takes place by a three-step mechanism which is depicted in the image below. The first step involves displacement of CoA from succinyl CoA by a nucleophilic inorganic phosphate molecule to form succinyl phosphate. The enzyme then utilizes a histidine residue to remove the phosphate group from succinyl phosphate and generate succinate. Finally, the phosphorylated histidine transfers the phosphate group to a nucleoside diphosphate, which generates the high-energy carrying nucleoside triphosphate.
Structure
Subunits
Bacterial and mammalian SCSs are made up of α and β subunits. In E. coli two αβ heterodimers link together to form an α2β2 heterotetrameric structure. However, mammalian mitochondrial SCSs are active as αβ dimers and do not form a heterotetramer.
The E. coli SCS heterotetramer has been crystallized and char |
https://en.wikipedia.org/wiki/Consumer%20Broadband%20and%20Digital%20Television%20Promotion%20Act | The Consumer Broadband and Digital Television Promotion Act (CBDTPA) () was a United States bill proposed in 2002 that would have prohibited any kind of technology that could be used to read digital content without digital rights management (DRM)—which prohibits copying and reading any content under copyright without permission of the copyright owner. The bill was known in early drafts as the Security Systems and Standards Certification Act (SSSCA) and was sometimes called the Consume But Don't Try Programming Act.
Legislation
The CBDTPA was proposed by South Carolina senator Fritz Hollings (D-SC). Senator Patrick Leahy (D-VT), chairman of the Senate Judiciary Committee, had stated that he could "not support" the proposed legislation and, as chairman, intended to block consideration of the controversial bill. This essentially killed the bill in 2002.
Proposed penalties for violating the CBDTPA ranged from five to twenty years in prison, and fines between $50,000 and $1 million.
Richard Stallman criticized this act due to the restrictions that it would place in the immediate and long-term future on free software, dubbing the bill the "Consume But Don't Try Programming Act."
Other U.S. senators named as sponsors of the CBDTPA bill include:
John Breaux (D-LA)
Dianne Feinstein (D-CA)
Daniel Inouye (D-HI)
Bill Nelson (D-FL)
Ted Stevens (R-AK)
See also
Trusted Computing
Trusted Computing Group
Trusted Platform Module |
https://en.wikipedia.org/wiki/Code%20page%20949%20%28IBM%29 | IBM code page 949 (IBM-949) is a character encoding which has been used by IBM to represent Korean language text on computers. It is a variable-width encoding which represents the characters from the Wansung code defined by the South Korean standard KS X 1001 in a format compatible with EUC-KR, but adds IBM extensions for additional hanja, additional precomposed Hangul syllables, and user-defined characters.
Giving values in hexadecimal, bytes 0x00 through 0x7F are used for single byte KS X 1003 (ISO 646:KR) characters, a similar set to ASCII but with a won sign rather than a backslash. Bytes 0x80 through 0x84 are used for IBM single byte extension characters. Lead bytes 0x8F through 0xA0 are used for IBM double byte extension characters. Lead bytes 0xA1 through 0xFE are used for Wansung code (KS X 1001 characters in EUC-KR form, double byte), but with some unused space opened up for user-defined use.
Although both are sometimes named "cp949", IBM-949 is different from Windows code page 949 (IBM-1363), which is Microsoft's Unified Hangul Code, a different extension of EUC-KR. It should also not be confused with IBM's implementation of plain EUC-KR (IBM-970). Code page 949 in OS/2 is the IBM code page; however, a third-party patch exists to change this.
Terminology and encoding labelling
Both IBM-949 and Unified Hangul Code (Windows-949) are known as "code page 949" (or "cp949") although they share only the EUC-KR subset in common. Neither has a standardised IANA-registered label to identify it. Although UHC is included in the WHATWG Encoding Standard, with labels including "windows-949", IBM-949 is not. IBM-949 therefore is not permitted in HTML5.
Although the meaning of the label "ibm-949" (and conversely "windows-949" and "ms949") is unambiguous where these labels are supported, the interpretation of the encoding labels "949" and "cp949" consequently varies between implementations. For example, International Components for Unicode uses "cp949", "949", "ibm-94 |
https://en.wikipedia.org/wiki/Cama%20%28animal%29 | A cama is a hybrid between a male dromedary camel and a female llama, and has been produced via artificial insemination at the Camel Reproduction Centre in Dubai. The first cama was born on January 14, 1998. The aim was to create an animal capable of higher wool production than the llama, with the size and strength of a camel and a cooperative temperament.
Breeding
The crossing was initially reported by The Ogdensburg Journal in 1871.
The dromedary has 74 diploid chromosomes, the same as other camelids. The autosomes consist of five pairs of small to medium-sized metacentrics and submetacentrics. The X chromosome is the largest in the metacentric and submetacentric group. There are 31 pairs of acrocentrics. The dromedary's karyotype is similar to that of the Bactrian camel.
As an adult dromedary camel can weigh up to six times as much as a llama, the hybrid needs to be produced by artificial insemination. Insemination of a female llama with sperm from a male dromedary camel has been the only successful combination. Inseminating a female camel with llama sperm has not produced viable offspring.
The first cama showed signs of becoming sexually mature at age four, when he showed a desire to breed with a female guanaco and a female llama. He was also a behavioral disappointment, displaying an extremely poor temperament. The second cama, a female named Kamilah, was successfully born in 2002. As of April 2008, five camas had been produced.
Food and drink
Much like camels, camas are herbivores that eat shrubs and other plant matter. As they can drink large amounts of water at a time, camas can survive with little or no water for long periods.
Comparison of camelids
The camelid family consists of the Old World camelids (the dromedary camels, Bactrian camels, and wild Bactrian camels) and the New World camelids (the llama, vicuna, suri alpaca, huacaya alpaca, and guanaco). Though there have been successful and fertile hybrids within each major groups of camelids, the |
https://en.wikipedia.org/wiki/Weak%20value | In quantum mechanics (and computation), a weak value is a quantity related to a shift of a measuring device's pointer when usually there is pre- and postselection. It should not be confused with a weak measurement, which is often defined in conjunction. The weak value was first defined by Yakir Aharonov, David Albert, and Lev Vaidman, published in Physical Review Letters 1988, and is related to the two-state vector formalism. There is also a way to obtain weak values without postselection.
Definition and Derivation
There are many excellent review articles on weak values (see e.g. ) here we briefly cover the basics.
Definition
We will denote the initial state of a system as , while the final state of the system is denoted as . We will refer to the initial and final states of the system as the pre- and post-selected quantum mechanical states. With respect to these states, the weak value of the observable is defined as:
Notice that if then the weak value is equal to the usual expected value in the initial state or the final state . In general the weak value quantity is a complex number. The weak value of the observable becomes large when the post-selected state, , approaches being orthogonal to the pre-selected state, , i.e. . If is larger than the largest eigenvalue of or smaller than the smallest eigenvalue of the weak value is said to be anomalous.
As an example consider a spin 1/2 particle. Take to be the Pauli Z operator with eigenvalues . Using the initial state
and the final state
we can calculate the weak value to be
For the weak value is anomalous.
Derivation
Here we follow the presentation given by Duck, Stevenson, and Sudarshan, (with some notational updates from Kofman et al. )which makes explicit when the approximations used to derive the weak value are valid.
Consider a quantum system that you want to measure by coupling an ancillary (also quantum) measuring device. The observable to be measured on the system is . The system and ancilla |
https://en.wikipedia.org/wiki/Chirp | A chirp is a signal in which the frequency increases (up-chirp) or decreases (down-chirp) with time. In some sources, the term chirp is used interchangeably with sweep signal. It is commonly applied to sonar, radar, and laser systems, and to other applications, such as in spread-spectrum communications (see chirp spread spectrum). This signal type is biologically inspired and occurs as a phenomenon due to dispersion (a non-linear dependence between frequency and the propagation speed of the wave components). It is usually compensated for by using a matched filter, which can be part of the propagation channel. Depending on the specific performance measure, however, there are better techniques both for radar and communication. Since it was used in radar and space, it has been adopted also for communication standards. For automotive radar applications, it is usually called linear frequency modulated waveform (LFMW).
In spread-spectrum usage, surface acoustic wave (SAW) devices are often used to generate and demodulate the chirped signals. In optics, ultrashort laser pulses also exhibit chirp, which, in optical transmission systems, interacts with the dispersion properties of the materials, increasing or decreasing total pulse dispersion as the signal propagates. The name is a reference to the chirping sound made by birds; see bird vocalization.
Definitions
The basic definitions here translate as the common physics quantities location (phase), speed (angular velocity), acceleration (chirpyness).
If a waveform is defined as:
then the instantaneous angular frequency, ω, is defined as the phase rate as given by the first derivative of phase,
with the instantaneous ordinary frequency, f, being its normalized version:
Finally, the instantaneous angular chirpyness (symbol γ) is defined to be the second derivative of instantaneous phase or the first derivative of instantaneous angular frequency,
Angular chirpyness has units of radians per square second (rad/s2); thus, i |
https://en.wikipedia.org/wiki/Gene%20H.%20Golub | Gene Howard Golub (February 29, 1932 – November 16, 2007), was an American numerical analyst who taught at Stanford University as Fletcher Jones Professor of Computer Science and held a courtesy appointment in electrical engineering.
Personal life
Born in Chicago, he was educated at the University of Illinois at Urbana-Champaign, receiving his B.S. (1953), M.A. (1954) and Ph.D. (1959) all in mathematics. His M.A. degree was more specifically in Mathematical Statistics. His PhD dissertation was entitled "The Use of Chebyshev Matrix Polynomials in the Iterative Solution of Linear Equations Compared to the Method of Successive Overrelaxation" and his thesis adviser was Abraham Taub. Gene Golub succumbed to acute myeloid leukemia on the morning of 16 November 2007 at the Stanford Hospital.
Stanford University
He arrived at Stanford in 1962 and became a professor there in 1970. He advised more than thirty doctoral students, many of whom have themselves achieved distinction. Gene Golub was an important figure in numerical analysis and pivotal to creating the NA-Net and the NA-Digest, as well as the International Congress on Industrial and Applied Mathematics.
One of his best-known books is Matrix Computations,
co-authored with Charles F. Van Loan. He was a major contributor to algorithms for matrix decompositions. In particular he published an algorithm together with William Kahan in 1970 that made the computation of the singular value decomposition (SVD) feasible and that is still used today. A survey of his work was published in 2007 by Oxford University Press as "Milestones in Matrix Computation".
Recognition
Golub was awarded the B. Bolzano Gold Medal for Merits in the Field of Mathematical Sciences and was one of the few elected to three national academies: the National Academy of Sciences (1993), the National Academy of Engineering (1990), and the American Academy of Arts and Sciences (1994). He was also a Foreign Member of the Royal Swedish Academy of Engineer |
https://en.wikipedia.org/wiki/Bessel%E2%80%93Maitland%20function | In mathematics, the Bessel–Maitland function, or Wright generalized Bessel function, is a generalization of the Bessel function, introduced by . The word "Maitland" in the name of the function seems to be the result of confusing Edward Maitland Wright's middle and last names. It is given by |
https://en.wikipedia.org/wiki/Selectron%20tube | The Selectron was an early form of digital computer memory developed by Jan A. Rajchman and his group at the Radio Corporation of America (RCA) under the direction of Vladimir K. Zworykin. It was a vacuum tube that stored digital data as electrostatic charges using technology similar to the Williams tube storage device. The team was never able to produce a commercially viable form of Selectron before magnetic-core memory became almost universal.
Development
Development of Selectron started in 1946 at the behest of John von Neumann of the Institute for Advanced Study, who was in the midst of designing the IAS machine and was looking for a new form of high-speed memory.
RCA's original design concept had a capacity of 4096 bits, with a planned production of 200 by the end of 1946. They found the device to be much more difficult to build than expected, and they were still not available by the middle of 1948. As development dragged on, the IAS machine was forced to switch to Williams tubes for storage, and the primary customer for Selectron disappeared. RCA lost interest in the design and assigned its engineers to improve televisions
A contract from the US Air Force led to a re-examination of the device in a 256-bit form. Rand Corporation took advantage of this project to switch their own IAS machine, the JOHNNIAC, to this new version of the Selectron, using 80 of them to provide 512 40-bit words of main memory. They signed a development contract with RCA to produce enough tubes for their machine at a projected cost of $500 per tube ($ in ).
Around this time IBM expressed an interest in the Selectron as well, but this did not lead to additional production. As a result, RCA assigned their engineers to color television development, and put the Selectron in the hands of "the mothers-in-law of two deserving employees (the Chairman of the Board and the President)."
Both the Selectron and the Williams tube were superseded in the market by the compact and cost-effectiv |
https://en.wikipedia.org/wiki/A.%20Hari%20Reddi | A. Hari Reddi (born October 20, 1942) is a Distinguished Professor and holder of the Lawrence J. Ellison Endowed Chair in Musculoskeletal Molecular Biology at the University of California, Davis. He was previously the Virginia M. and William A. Percy Chair and Professor in Orthopaedic Surgery, Professor of Biological Chemistry, and Professor of Oncology at the Johns Hopkins University School of Medicine. Professor Reddi's research played an indispensable role in the identification, isolation and purification of bone morphogenetic proteins (BMPs) that are involved in bone formation and repair. The molecular mechanism of bone induction studied by Professor Reddi led to the conceptual advance in tissue engineering that morphogens in the form of metabologens bound to an insoluble extracellular matrix scaffolding act in collaboration to stimulate stem cells to form cartilage and bone. The Reddi laboratory has also made important discoveries unraveling the role of the extracellular matrix in bone and cartilage tissue regeneration and repair.
Significant research accomplishments
Professor Reddi discovered that bone induction is a sequential multistep cascade involving chemotaxis, mitosis, and differentiation. Early studies in his laboratory at the University of Chicago and National Institutes of Health unraveled the sequence of events involved in bone matrix-induce bone morphogenesis. Using a battery of in vitro and in vivo bioassays for bone formation, a systematic study was undertaken in his laboratory to isolate and purify putative bone morphogenetic proteins. Reddi and colleagues were the first to identify BMPs as pleiotropic regulators, acting in a concentration dependent manner. They demonstrated first that BMPs bind the extracellular matrix, are present at the apical ectodermal ridge in the developing limb bud, are chemotactic for human monocytes, and have neurotropic potential. His laboratory pioneered the use of BMPs in regenerative orthopedics and dentist |
https://en.wikipedia.org/wiki/List%20of%20U.S.%20state%20fossils | Most American states have made a state fossil designation, in many cases during the 1980s. It is common to designate one species in which fossilization has occurred, rather than a single specimen, or a category of fossils not limited to a single species.
Some states that lack an explicit state fossil have nevertheless singled out a fossil for formal designation as a state dinosaur, rock, gem or stone.
Table of state fossils
States lacking a state fossil
Arkansas
Hawaii
Minnesota
The giant beaver was proposed in 2022.
Iowa
The crinoid was proposed in 2018.
New Hampshire
The American mastodon (Mammut americanum) was considered in 2015.
New Jersey
Rhode Island
Texas
The state dinosaur of Texas is Sauroposeidon proteles.
See also
List of U.S. state dinosaurs
List of U.S. state minerals, rocks, and gemstones
Lists of U.S. state insignia |
https://en.wikipedia.org/wiki/Gastrocolic%20reflex | The gastrocolic reflex or gastrocolic response is a physiological reflex that controls the motility, or peristalsis, of the gastrointestinal tract following a meal. It involves an increase in motility of the colon consisting primarily of giant migrating contractions, or migrating motor complexes, in response to stretch in the stomach following ingestion and byproducts of digestion entering the small intestine. Thus, this reflex is responsible for the urge to defecate following a meal. The small intestine also shows a similar motility response. The gastrocolic reflex's function in driving existing intestinal contents through the digestive system helps make way for ingested food.
The reflex was demonstrated by myoelectric recordings in the colons of animals and humans, which showed an increase in electrical activity within as little as 15 minutes after eating. The recordings also demonstrated that the gastrocolic reflex is uneven in its distribution throughout the colon. The sigmoid colon is more greatly affected than the rest of the colon in terms of a phasic response, recurring periods of contraction followed by relaxation, in order to propel food distally into the rectum; however, the tonic response across the colon is uncertain. These contractions are generated by the muscularis externa stimulated by the myenteric plexus. When pressure within the rectum becomes increased, the gastrocolic reflex acts as a stimulus for defecation. A number of neuropeptides have been proposed as mediators of the gastrocolic reflex. These include serotonin, neurotensin, cholecystokinin, prostaglandin E1, and gastrin.
Coffee can induce a significant response, with 29% of subjects in a study reporting an urge to defecate after ingestion, and manometry showing a reaction typically between 4 and 30 minutes after consumption and potentially lasting for more than 30 minutes. Decaffeinated coffee is also capable of generating a similar effect, albeit slightly weaker. Essentially, this m |
https://en.wikipedia.org/wiki/Ribosome-binding%20site | A ribosome binding site, or ribosomal binding site (RBS), is a sequence of nucleotides upstream of the start codon of an mRNA transcript that is responsible for the recruitment of a ribosome during the initiation of translation. Mostly, RBS refers to bacterial sequences, although internal ribosome entry sites (IRES) have been described in mRNAs of eukaryotic cells or viruses that infect eukaryotes. Ribosome recruitment in eukaryotes is generally mediated by the 5' cap present on eukaryotic mRNAs.
Prokaryotes
The RBS in prokaryotes is a region upstream of the start codon. This region of the mRNA has the consensus 5'-AGGAGG-3', also called the Shine-Dalgarno (SD) sequence. The complementary sequence (CCUCCU), called the anti-Shine-Dalgarno (ASD) is contained in the 3’ end of the 16S region of the smaller (30S) ribosomal subunit. Upon encountering the Shine-Dalgarno sequence, the ASD of the ribosome base pairs with it, after which translation is initiated.
Variations of the 5'-AGGAGG-3' sequence have been found in Archaea as highly conserved 5′-GGTG-3′ regions, 5 basepairs upstream of the start site. Additionally, some bacterial initiation regions, such as rpsA in E.coli completely lack identifiable SD sequences.
Effect on translation initiation rate
Prokaryotic ribosomes begin translation of the mRNA transcript while DNA is still being transcribed. Thus translation and transcription are parallel processes. Bacterial mRNA are usually polycistronic and contain multiple ribosome binding sites. Translation initiation is the most highly regulated step of protein synthesis in prokaryotes.
The rate of translation depends on two factors:
the rate at which a ribosome is recruited to the RBS
the rate at which a recruited ribosome is able to initiate translation (i.e. the translation initiation efficiency)
The RBS sequence affects both of these factors.
Factors affecting rate of ribosome recruitment
The ribosomal protein S1 binds to adenine sequences upstream of the |
https://en.wikipedia.org/wiki/Phototrophic%20biofilm | Phototrophic biofilms are microbial communities generally comprising both phototrophic microorganisms, which use light as their energy source, and chemoheterotrophs. Thick laminated multilayered phototrophic biofilms are usually referred to as microbial mats or phototrophic mats (see also biofilm). These organisms, which can be prokaryotic or eukaryotic organisms like bacteria, cyanobacteria, fungi, and microalgae, make up diverse microbial communities that are affixed in a mucous matrix, or film. These biofilms occur on contact surfaces in a range of terrestrial and aquatic environments. The formation of biofilms is a complex process and is dependent upon the availability of light as well as the relationships between the microorganisms. Biofilms serve a variety of roles in aquatic, terrestrial, and extreme environments; these roles include functions which are both beneficial and detrimental to the environment. In addition to these natural roles, phototrophic biofilms have also been adapted for applications such as crop production and protection, bioremediation, and wastewater treatment.
Biofilm formation
Biofilm formation is a complicated process which occurs in four general steps: attachment of cells, formation of the colony, maturation, and cell dispersal. These films can grow in sizes ranging from microns to centimeters in thickness. Most are green and/or brown, but can be more colorful.
Biofilm development is dependent on the generation of extracellular polymeric substances (EPS) by microorganisms. The EPS, which is akin to a gel, is a matrix which provides structure for the biofilm and is essential for growth and functionality. It consists of organic compounds such as polysaccharides, proteins, and glycolipids and may also include inorganic substances like silt and silica. EPS join cells together in the biofilm and transmits light to organisms in the lower zone. Additionally, EPS serves as an adhesive for surface attachment and facilitates digestion of nutr |
https://en.wikipedia.org/wiki/700%20%28number%29 | 700 (seven hundred) is the natural number following 699 and preceding 701.
It is the sum of four consecutive primes (167 + 173 + 179 + 181), the perimeter of a Pythagorean triangle (75 + 308 + 317) and a Harshad number.
Integers from 701 to 799
Nearly all of the palindromic integers between 700 and 800 (i.e. nearly all numbers in this range that have both the hundreds and units digit be 7) are used as model numbers for Boeing Commercial Airplanes.
700s
701 = prime number, sum of three consecutive primes (229 + 233 + 239), Chen prime, Eisenstein prime with no imaginary part
702 = 2 × 33 × 13, pronic number, nontotient, Harshad number
703 = 19 × 37, triangular number, hexagonal number, smallest number requiring 73 fifth powers for Waring representation, Kaprekar number, area code for Northern Virginia along with 571, a number commonly found in the formula for body mass index
704 = 26 × 11, Harshad number, lazy caterer number , area code for the Charlotte, NC area.
705 = 3 × 5 × 47, sphenic number, smallest Bruckman-Lucas pseudoprime
706 = 2 × 353, nontotient, Smith number
707 = 7 × 101, sum of five consecutive primes (131 + 137 + 139 + 149 + 151), palindromic number, number of lattice paths from (0,0) to (5,5) with steps (0,1), (1,0) and, when on the diagonal, (1,1).
708 = 22 × 3 × 59, number of partitions of 28 that do not contain 1 as a part
709 = prime number; happy number. It is the seventh in the series 2, 3, 5, 11, 31, 127, 709 where each number is the nth prime with n being the number proceeding it in the series, therefore, it is a prime index number.
710s
710 = 2 × 5 × 71, sphenic number, nontotient, number of forests with 11 vertices
711 = 32 × 79, Harshad number, number of planar Berge perfect graphs on 7 nodes. Also the phone number of Telecommunications Relay Service, commonly used by the deaf and hard-of-hearing.
712 = 23 × 89, refactorable number, sum of the first twenty-one primes, totient sum for first 48 integers. It is the largest k |
https://en.wikipedia.org/wiki/Apostrophe | The apostrophe ( or ) is a punctuation mark, and sometimes a diacritical mark, in languages that use the Latin alphabet and some other alphabets. In English, the apostrophe is used for two basic purposes:
The marking of the omission of one or more letters, e.g. the contraction of "do not" to "don't".
The marking of possessive case of nouns (as in "the eagle's feathers", "in one month's time", "the twins' coats").
It is also used in a few distinctive cases for the marking of plurals, e.g. "p's and q's" or Oakland A's.
The word "apostrophe" comes ultimately from Greek (, '[the accent of] turning away or elision'), through Latin and French.
Usage in English
Historical development
The apostrophe was first used by Pietro Bembo in his edition of De Aetna (1496). It was introduced into English in the 16th century in imitation of French practice.
French practice
Introduced by Geoffroy Tory (1529), the apostrophe was used in place of a vowel letter to indicate elision (as in in place of ). It was also frequently used in place of a final "e" (which was still pronounced at the time) when it was elided before a vowel, as in . Modern French orthography has restored the spelling .
Early English practice
From the 16th century, following French practice, the apostrophe was used when a vowel letter was omitted either because of incidental elision ("I'm" for "I am") or because the letter no longer represented a sound ("lov'd" for "loved"). English spelling retained many inflections that were not pronounced as syllables, notably verb endings ("-est", "-eth", "-es", "-ed") and the noun ending "-es", which marked either plurals or possessives, also known as genitives . An apostrophe followed by "s" was often used to mark a plural; specifically, the Oxford Companion to the English Language notes that
There was formerly a respectable tradition (17th to 19th centuries) of using the apostrophe for noun plurals, especially in loanwords ending in a vowel (as in ... Comma's are used |
https://en.wikipedia.org/wiki/Kim%20Thomas | Kim Susannah Thomas (born 10 October 1967) is a former competitive rower from Great Britain.
Early life
Thomas was born in 1967 in Wandsworth, Great Britain. She is a member of the Leander Club at Henley-on-Thames. She received her education at Surbiton High School in Surbiton, and then studied engineering at Durham University. She then trained as a teacher concentrating on physics, but later focussed on mathematics.
Rowing career
She competed at the World Rowing Junior Championships in 1983, 1984, and 1985. In 1983 in Vichy, France, she came fifth with the junior women's eight. In 1984 in Jönköping, Sweden, she came sixth in the junior women's coxed four. A year later in the same boat class but with a different team, she came fifth.
In 1987, Thomas competed at senior level and was part of the coxless pairs with Alison Bonner that won the national title rowing for a Kingston and Weybridge Ladies composite, at the 1987 National Championships and at that year's World Rowing Championships, she competed in the women's pair with Alison Bonner and they came seventh. Thomas and Bonner competed at the 1988 Summer Olympics in the coxless pair and came eighths. At the 1989 World Rowing Championships at Lake Bled near Bled in SR Slovenia, Yugoslavia, she teamed up with Catherine Miller in the women's pair and they came in eleventh (and last) place.
At the 1992 Summer Olympics, she was a member of Great Britain's coxless four, and the team came eighths in the competition. She was a member of the Durham University Boat Club from 1989 to 1991.
In 1989, Thomas was the second recipient of The Sunday Times Sportswoman of the Year award.
Professional career
Thomas' first teaching role was at Kingston Grammar School, where she joined their mathematics department. Where she taught the son of Richard Henry Biffa of BIffa bins. After two years in that role, she went to Pangbourne College as head of mathematics.
At present, she is a teacher at Albyn School in Aberdeen, Scotland, an |
https://en.wikipedia.org/wiki/Claudia%20Wilds%20Award | The ABA Claudia Wilds Award for Distinguished Service is an award given by the American Birding Association to a member who has given "long and useful service to the organization," either as a volunteer or as compensated staff, in recognition of the member's dedicated energy and years of service.
One of five awards presented by the ABA for contributions to birding, the award is named in honor of Claudia Wilds (1931-1997), who made many contributions to ornithology and the ABA. Wilds was author of an important birdfinding guide to the mid-Atlantic states and co-author of a handbook of the world's terns and skimmers, completed after her death. Wilds served on the board of the ABA, was an associate editor of Birding magazine, wrote articles for The Audubon Society Master Guide to Birding, and was a consultant in the preparation of the National Geographic Society's field guide. She herself was posthumously awarded the ABA's Ludlow Griscom Award in 1998.
The Claudia Wilds Award was first bestowed on Larry Balch.
List of recipients
The award was introduced in 2000.
Source:
See also
List of ornithology awards |
https://en.wikipedia.org/wiki/Cistercian%20numerals | The medieval Cistercian numerals, or "ciphers" in nineteenth-century parlance, were developed by the Cistercian monastic order in the early thirteenth century at about the time that Arabic numerals were introduced to northwestern Europe. They are more compact than Arabic or Roman numerals, with a single glyph able to indicate any integer from 1 to 9,999.
Digits are based on a horizontal or vertical stave, with the position of the digit on the stave indicating its place value (units, tens, hundreds or thousands). These digits are compounded on a single stave to indicate more complex numbers. The Cistercians eventually abandoned the system in favor of the Arabic numerals, but marginal use outside the order continued until the early twentieth century.
History
The digits and idea of forming them into ligatures were apparently based on a two-place (1–99) numeral system introduced into the Cistercian Order by John of Basingstoke, archdeacon of Leicester, who it seems based them on a twelfth-century English shorthand (ars notaria). In its earliest attestations, in the monasteries of the County of Hainaut, the Cistercian system was not used for numbers greater than 99, but it was soon expanded to four places, enabling numbers up to 9,999.
The two dozen or so surviving Cistercian manuscripts that use the system date from the thirteenth to the fifteenth century, and cover an area from England to Italy, Normandy to Sweden. The numbers were not used for arithmetic, fractions or accounting, but indicated years, foliation (numbering pages), divisions of texts, the numbering of notes and other lists, indexes and concordances, arguments in Easter tables, and the lines of a staff in musical notation.
Although mostly confined to the Cistercian order, there was some usage outside it. A late-fifteenth-century Norman treatise on arithmetic used both Cistercian and Indo-Arabic numerals. In one known case, Cistercian numerals were inscribed on a physical object, indicating the cale |
https://en.wikipedia.org/wiki/Confusion%20of%20the%20inverse | Confusion of the inverse, also called the conditional probability fallacy or the inverse fallacy, is a logical fallacy whereupon a conditional probability is equated with its inverse; that is, given two events A and B, the probability of A happening given that B has happened is assumed to be about the same as the probability of B given A, when there is actually no evidence for this assumption. More formally, P(A|B) is assumed to be approximately equal to P(B|A).
Examples
Example 1
In one study, physicians were asked to give the chances of malignancy with a 1% prior probability of occurring. A test can detect 80% of malignancies and has a 10% false positive rate. What is the probability of malignancy given a positive test result? Approximately 95 out of 100 physicians responded the probability of malignancy would be about 75%, apparently because the physicians believed that the chances of malignancy given a positive test result were approximately the same as the chances of a positive test result given malignancy.
The correct probability of malignancy given a positive test result as stated above is 7.5%, derived via Bayes' theorem:
Other examples of confusion include:
Hard drug users tend to use marijuana; therefore, marijuana users tend to use hard drugs (the first probability is marijuana use given hard drug use, the second is hard drug use given marijuana use).
Most accidents occur within 25 miles from home; therefore, you are safest when you are far from home.
Terrorists tend to have an engineering background; so, engineers have a tendency towards terrorism.
For other errors in conditional probability, see the Monty Hall problem and the base rate fallacy. Compare to illicit conversion.
Example 2
In order to identify individuals having a serious disease in an early curable form, one may consider screening a large group of people. While the benefits are obvious, an argument against such screenings is the disturbance caused by false positive screening |
https://en.wikipedia.org/wiki/Thermodynamic%20cycle | A thermodynamic cycle consists of linked sequences of thermodynamic processes that involve transfer of heat and work into and out of the system, while varying pressure, temperature, and other state variables within the system, and that eventually returns the system to its initial state. In the process of passing through a cycle, the working fluid (system) may convert heat from a warm source into useful work, and dispose of the remaining heat to a cold sink, thereby acting as a heat engine. Conversely, the cycle may be reversed and use work to move heat from a cold source and transfer it to a warm sink thereby acting as a heat pump. If at every point in the cycle the system is in thermodynamic equilibrium, the cycle is reversible. Whether carried out reversible or irreversibly, the net entropy change of the system is zero, as entropy is a state function.
During a closed cycle, the system returns to its original thermodynamic state of temperature and pressure. Process quantities (or path quantities), such as heat and work are process dependent. For a cycle for which the system returns to its initial state the first law of thermodynamics applies:
The above states that there is no change of the internal energy () of the system over the cycle. represents the total work and heat input during the cycle and would be the total work and heat output during the cycle. The repeating nature of the process path allows for continuous operation, making the cycle an important concept in thermodynamics. Thermodynamic cycles are often represented mathematically as quasistatic processes in the modeling of the workings of an actual device.
Heat and work
Two primary classes of thermodynamic cycles are power cycles and heat pump cycles. Power cycles are cycles which convert some heat input into a mechanical work output, while heat pump cycles transfer heat from low to high temperatures by using mechanical work as the input. Cycles composed entirely of quasistatic processes can operate |
https://en.wikipedia.org/wiki/Diethylcarbamazine | Diethylcarbamazine is a medication used in the treatment of filariasis including lymphatic filariasis, tropical pulmonary eosinophilia, and loiasis. It may also be used for prevention of loiasis in those at high risk. While it has been used for onchocerciasis (river blindness), ivermectin is preferred. It is taken by mouth.
Common side effects include itching, facial swelling, headaches, and feeling tired. Other side effects include vision loss and dizziness. It is a recommended treatment in pregnancy and appears to be safe for the baby. The World Health Organization; however, recommends waiting until after pregnancy for treatment when feasible. It is made from 4-methyl-piperazine.
Diethylcarbamazine was discovered in 1947 by Yellapragada Subbarow. It is on the World Health Organization's List of Essential Medicines. It is not commercially available in the United States but can be acquired from the Centers for Disease Control and Prevention.
Medical uses
Diethylcarbamazine is indicated for the treatment of people with certain filarial diseases, including lymphatic filariasis caused by infection with Wuchereria bancrofti, Brugia malayi, or Brugia timori; loiasis and tropical pulmonary eosinophilia.The WHO recommends prescribing diethylcarbamazine to people who are infected with microfilariae of filarial parasites and also to control transmission of infection in filariasis-endemic areas.
In India and China, diethylcarbamazine has been added to salt to combat lymphatic filariasis.
Contraindications
Contraindications are previous history of heart problems, gastrointestinal problems, and allergies.
Diethylcarbamazine is contraindicated in patients who may have onchocerciasis, due to the risk of the Mazzotti reaction.
Mechanism
Diethylcarbamazine is an inhibitor of arachidonic acid metabolism in microfilariae. This makes the microfilariae more susceptible to innate immune attack, but does not kill the parasites outright.
Society and culture
Brand names
Brand na |
https://en.wikipedia.org/wiki/Cathode-ray%20tube%20amusement%20device | The cathode-ray tube amusement device is the earliest known interactive electronic game as well as the first game to incorporate an electronic display. The device simulates an artillery shell arcing towards targets on a cathode-ray tube (CRT) screen, which is controlled by the player by adjusting knobs to change the trajectory of a CRT beam spot on the display in order to reach plastic targets overlaid on the screen. Thomas T. Goldsmith Jr. and Estle Ray Mann constructed the game from analog electronics and filed for a patent in 1947, which was issued the following year. The gaming device was never manufactured or marketed to the public, so it had no effect on the future video game industry. Under many definitions, the device is not considered a video game, as while it had an electronic display it did not run on a computing device. Therefore, despite its relevance to the early history of video games, it is not generally considered a candidate for the title of the first video game.
Gameplay
The cathode-ray tube amusement device consists of a cathode-ray tube (CRT) connected to basic oscilloscope type circuitry with a set of knobs and switches. The device also incorporates very simple analog circuitry and does not use any digital computer or memory device or execute a program. The CRT projects a spot on the display screen, which traces a curved arc across the screen when a switch is activated by the player. This beam spot represents the trajectory of an artillery shell. The curved path is produced by the CRT, which is not of conventional design, deflecting the beam of electrons as the spot moves across the screen. Overlaid on the screen are transparent plastic targets representing objects such as airplanes. At the end of the spot's trajectory, the beam defocuses, resulting in the spot expanding and blurring. This represents the shell exploding as if detonated by a time fuze. The goal of the game is to have the beam defocus when it is within the bounds of a target. P |
https://en.wikipedia.org/wiki/Farthest-first%20traversal | In computational geometry, the farthest-first traversal of a compact metric space is a sequence of points in the space, where the first point is selected arbitrarily and each successive point is as far as possible from the set of previously-selected points. The same concept can also be applied to a finite set of geometric points, by restricting the selected points to belong to the set or equivalently by considering the finite metric space generated by these points. For a finite metric space or finite set of geometric points, the resulting sequence forms a permutation of the points, also known as the greedy permutation.
Every prefix of a farthest-first traversal provides a set of points that is widely spaced and close to all remaining points. More precisely, no other set of equally many points can be spaced more than twice as widely, and no other set of equally many points can be less than half as far to its farthest remaining point. In part because of these properties, farthest-point traversals have many applications, including the approximation of the traveling salesman problem and the metric -center problem. They may be constructed in polynomial time, or (for low-dimensional Euclidean spaces) approximated in near-linear time.
Definition and properties
A farthest-first traversal is a sequence of points in a compact metric space, with each point appearing at most once. If the space is finite, each point appears exactly once, and the traversal is a permutation of all of the points in the space. The first point of the sequence may be any point in the space. Each point after the first must have the maximum possible distance to the set of points earlier than in the sequence, where the distance from a point to a set is defined as the minimum of the pairwise distances to points in the set. A given space may have many different farthest-first traversals, depending both on the choice of the first point in the sequence (which may be any point in the space) and on ties fo |
https://en.wikipedia.org/wiki/Old%20Weather | Old Weather is an online weather data project that currently invites members of the public to assist in digitising weather observations recorded in US log books dating from the mid-19th century onwards. It is an example of citizen science that enlists members of the public to help in scientific research. It contributes to the Atmospheric Circulation Reconstructions over the Earth initiative. Data collected by Old Weather has been used by at least five different climate reanalysis projects, including HURDAT, SODA and ECMWF. In February 2013, the project was awarded the Royal Meteorological Society IBM Award for Meteorological Innovation that Matters.
Origins
Old Weather is a Zooniverse project and is a collaboration between researchers at many institutions, including the University of Oxford, Oxford Martin School, ACRE (International Atmospheric Circulation Reconstructions over the Earth), Naval-History.Net of Penarth, Jisc which encourages UK colleges and universities in the innovative use of digital technologies, the National Maritime Museum at Maritime Greenwich, London, and the UK National Archives, Kew, London.
Importance of volunteers
In the past, computer programs have proved unable to read handwriting reliably.
However, it may be worth exploring the current status
of automatic and computer-assisted transcription
and probabilistic indexing
technologies for handwritten text images—also called Handwriting Text Recognition (HTR), Computer Assisted Transcription of Text Images (CATTI) and Keyword Spotting (KWS), respectively).
In any case, the task is much better performed by the human brain and the results transferred to a digital form.
In the site's tutorial, would-be volunteers are shown how to digitise a weather record. Further instructions on how to transcribe the logs are available on the associated Old Weather forum.
It is intended that the pages of the logs are digitised by at least three people. The results will be used to make climate model projectio |
https://en.wikipedia.org/wiki/TomSym | The TomSym MATLAB symbolic modeling engine is a platform for modeling applied optimization and optimal control problems.
Description
TomSym is complete modeling environment in Matlab with support for most built-in mathematical operators in Matlab. It is a combined modeling, compilation and interface to the TOMLAB solvers. The matrix derivative of a matrix function is a fourth rank tensor - that is, a matrix each of whose entries is a matrix. Rather than using four-dimensional matrices to represent this, TomSym continues to work in two dimensions. This makes it possible to take advantage of the very efficient handling of sparse matrices in Matlab, which is not available for higher-dimensional matrices.
TomSym has a variety of functions, among them:
Ability to transform expressions and generate analytical first and second order derivatives, including sparsity patterns.
Interfaced and compatible with MAD, i.e. MAD can be used when symbolic modeling is not suitable.
Numerical differentiation can be used to parts of the model.
Functionality for plotting and computing a variety of information for the solution to the problem.
Support for if, then, else statements.
Ability to analyze p-coded Matlab files.
Automated code simplification for generated models, for example.
Multiplication by 1 or the identity matrix is eliminated: 1*A = A
Addition/subtraction of 0 is eliminated: 0+A = A
All-same matrices are reduced to scalars: [3;3;3]+x = 3+x
Scalars are moved to the left in addition/subtraction: A-y = -y+A
Inverse operations cancel: sqrt(x)^2 = x
Modeling
The TomSym symbolic source transformation makes it possible to define any the set of decision variables (both continuous and integer) and any type of constraint as well as scalars and constant parameters.
Linear programming
An example linear programming problem would look like this:
c = [-7; -5];
A = [ 1 2
4 1 ];
b_U = [ 6; 12 ];
x_L = [ 0; 0 ];
toms 2x1 x
solution = ezsolve(c'*x, {A*x |
https://en.wikipedia.org/wiki/Zona%20pellucida-like%20domain | The Zona pellucida-like domain (ZP domain / ZP-like domain / ZP module) is a large protein region of about 260 amino acids. It has been recognised in a variety of receptor-like eukaryotic glycoproteins. All of these molecules are mosaic proteins with a large extracellular region composed of various domains, often followed by either a transmembrane region and a very short cytoplasmic region or by a GPI-anchor.
Functional and crystallographic studies revealed that the "ZP domain" region common to all these proteins is a protein polymerization module that consists of two distinct but structurally related immunoglobulin-like domains, ZP-N and ZP-C. The ZP module is located in the C-terminal portion of the extracellular region and – with the exception of non-polymeric family member ENG – contains 8 or 10 conserved Cys residues involved in disulfide bonds.
The first 3D structure of a ZP module protein filament, native human uromodulin (UMOD), was determined by cryo-EM.
Additional copies of isolated ZP-N domains are found in the N-terminal region of egg coat protein subunits involved in fertilization in both vertebrates and invertebrates, such as human zona pellucida components ZP1, ZP2 and ZP4 and mollusk vitelline envelope receptor for egg lysin (VERL).
Examples
Humans genes encoding proteins containing this domain include:
CUZD1
DMBT1
ENG
GP2
OIT3
POMZP3
TECTA, TECTB, TGFBR3
UMOD, UMODL1
ZP1, ZP2, ZP3, ZP4, ZPLD1 |
https://en.wikipedia.org/wiki/Forma%20specialis | Forma specialis (plural: formae speciales), abbreviated f. sp. (plural ff. spp.) without italics, is an informal taxonomic grouping allowed by the International Code of Nomenclature for algae, fungi, and plants, that is applied to a parasite (most frequently a fungus) which is adapted to a specific host. This classification may be applied by authors who do not feel that a subspecies or variety name is appropriate, and it is therefore not necessary to specify morphological differences that distinguish this form. The literal meaning of the term is 'special form', but this grouping does not correspond to the more formal botanical use of the taxonomic rank of forma or form.
An example is Puccinia graminis f. sp. avenae, which affects oats.
An alternative term in contexts not related to biological nomenclature is physiological race (sometimes also given as biological race, and in that context treated as synonymous with biological form), except in that the name of a race is added after the binomial scientific name (and may be arbitrary, e.g. an alphanumeric code, usually with the word "race"), e.g. "Podosphaera xanthii race S". A forma specialis is used as part of the infraspecific scientific name (and follows Latin-based scientific naming conventions), inserted after the interpolation "f. sp.", as in the "Puccinia graminis f. sp. avenae" example.
History, and use with "pathotype"
The forma specialis category was introduced and recommended in the International Code of Botanical Nomenclature of 1930, but was not widely adopted. Fungal pathogens within Alternaria alternata species have also been called pathotypes (not to be confused with pathotype as used in bacteriology) by author Syoyo Nishimura who stated:"[E]ach pathogen should be called a distinct pathotype of A. alternata"
Some authors have subsequently used forma specialis and "pathotype" together for the species A. alternata: "Currently there are seven pathotypes of A. alternata described ..., but this term is |
https://en.wikipedia.org/wiki/Engineered%20cellular%20magmatic | Engineered cellular magmatics (ECMs) are synthetic stone of glass and ceramic. ECMs replicate rare, naturally occurring volcanic materials, and exhibit useful structural and chemical properties of those materials. The US Department of Energy has recognized ECMs as an advanced material, funding further research into the manufacture and application of ECMs through ARPA-E and Savannah River National Laboratory.
Properties
ECMs can be engineered to include a broad range of silicate species, with various reactivity. Their physical structure can range from closed to open cell, resembling pumice or porous ceramic. They can be composed of internal pore and vesicular structures with individual cross sections that can measure from millimeter down to nanometer scale. Open cell varieties exhibit extensive surface areas which amplify ion exchange capabilities (both cationic and anionic). These features make them well suited for various cement construction filtration and remediation applications. They typically contain both amorphous and crystalline structures.
Application
Known uses for ECMs include air and water filtration, biological and chemical remediation, microbial habitat, soil and cementitious amendments. They can also be used in the manufacture of various forms of zeolite due to the resulting silicate lattice, and in various reactors for chemical separation. They meet and exceed the ASTM Standard Specification for Lightweight Aggregates for Structural Concrete, and exceed ASTM standards for vegetative green roof media.
History
ECMs share a history with foam glass, but are engineered for specific chemical reactivity and structural properties not generally considered the domain of foam glass. The term engineered cellular magmatic was adopted to describe the material in late 2019 by inventor Robert Hust. Other named inventors include Gene Ramsey, Cory Trivelpiece, Gert Nielsen, and Philip Galland.
Manufacture
ECMs can be manufactured from raw materials (minerals w |
https://en.wikipedia.org/wiki/Abel%20equation | The Abel equation, named after Niels Henrik Abel, is a type of functional equation of the form
or
.
The forms are equivalent when is invertible. or control the iteration of .
Equivalence
The second equation can be written
Taking , the equation can be written
For a known function , a problem is to solve the functional equation for the function , possibly satisfying additional requirements, such as .
The change of variables , for a real parameter , brings Abel's equation into the celebrated Schröder's equation, .
The further change into Böttcher's equation, .
The Abel equation is a special case of (and easily generalizes to) the translation equation,
e.g., for ,
. (Observe .)
The Abel function further provides the canonical coordinate for Lie advective flows (one parameter Lie groups).
History
Initially, the equation in the more general form
was reported. Even in the case of a single variable, the equation is non-trivial, and admits special analysis.
In the case of a linear transfer function, the solution is expressible compactly.
Special cases
The equation of tetration is a special case of Abel's equation, with .
In the case of an integer argument, the equation encodes a recurrent procedure, e.g.,
and so on,
Solutions
The Abel equation has at least one solution on if and only if for all and all , , where , is the function iterated times.
Analytic solutions (Fatou coordinates) can be approximated by asymptotic expansion of a function defined by power series in the sectors around a parabolic fixed point. The analytic solution is unique up to a constant.
See also
Functional equation
Schröder's equation
Böttcher's equation
Infinite compositions of analytic functions
Iterated function
Shift operator
Superfunction |
https://en.wikipedia.org/wiki/Jane%20Poynter | Jane Poynter is an American aerospace executive, author and speaker. She is founder, co-CEO and CXO of Space Perspective, a luxury space travel company. She was co-founder and former CEO of World View Enterprises, a private near-space exploration and technology company headquartered in Tucson, Arizona. Poynter was also a founding member of the Biosphere 2 design team and a crew member from the original two-year mission inside the materially closed ecological system.
Prior to World View, Poynter served as co-founder, Chairwoman and President of Paragon Space Development Corporation, a designer and manufacturer of hazardous environment life support equipment.
Business ventures
Space Perspective
Space Perspective is a high-altitude flight tourism company, founded and incorporated in 2019 by Poynter and Taber MacCallum, with plans to launch its nine-person Spaceship Neptune crewed balloon from NASA Kennedy Space Center.
On June 18, 2020, Space Perspective announced plans to balloon passengers to nearly above the Earth. The tickets are US$125,000 per seat.
On 2 December 2020, Space Perspective closed its seed funding round. US$7 million of funding had been gathered. The company planned the first uncrewed test flight in the first half of 2021 and crewed operational flights by end of 2024.
World View Enterprises
World View Enterprises, doing business as World View, is a private American near-space exploration and technology company headquartered in Tucson, Arizona, founded with the goal of increasing access to and the utilization of the stratosphere for scientific, commercial, and economic purposes.
World View was founded and incorporated in 2012 by a team of aerospace and life support veterans, including Biosphere 2 crew-members Poynter and Taber MacCallum, Alan Stern (the principal investigator of the New Horizons mission to Pluto), and former NASA astronaut Mark Kelly. The company designs, manufactures and operates stratospheric flight technology for a variety o |
https://en.wikipedia.org/wiki/Read-copy-update | In computer science, read-copy-update (RCU) is a synchronization mechanism that avoids the use of lock primitives while multiple threads concurrently read and update elements that are linked through pointers and that belong to shared data structures (e.g., linked lists, trees, hash tables).
Whenever a thread is inserting or deleting elements of data structures in shared memory, all readers are guaranteed to see and traverse either the older or the new structure, therefore avoiding inconsistencies (e.g., dereferencing null pointers).
It is used when performance of reads is crucial and is an example of space–time tradeoff, enabling fast operations at the cost of more space. This makes all readers proceed as if there were no synchronization involved, hence they will be fast, but also making updates more difficult.
Name and overview
The name comes from the way that RCU is used to update a linked structure in place. A thread wishing to do this uses the following steps:
create a new structure,
copy the data from the old structure into the new one, and save a pointer to the old structure,
modify the new, copied, structure,
update the global pointer to refer to the new structure,
sleep until the operating system kernel determines that there are no readers left using the old structure, for example, in the Linux kernel, by using ,
once awakened by the kernel, deallocate the old structure.
So the structure is read concurrently with a thread copying in order to do an update, hence the name "read-copy update". The abbreviation "RCU" was one of many contributions by the Linux community. Other names for similar techniques include passive serialization and MP defer by VM/XA programmers and generations by K42 and Tornado programmers.
Detailed description
A key property of RCU is that readers can access a data structure even when it is in the process of being updated: RCU updaters cannot block readers or force them to retry their accesses. This overview starts by showing |
https://en.wikipedia.org/wiki/Ralph%20Duncan%20James | Ralph Duncan James (8 February 1909, Liverpool, England – 19 May 1979, Salt Spring Island, British Columbia, Canada) was a Canadian mathematician working on number theory and mathematical analysis.
Born in Liverpool, Ralph moved with his parents to Vancouver, British Columbia when he was 10 years old. After graduating from high school, Ralph attended University of British Columbia. After graduating, he continued in mathematics, writing a master’s thesis on Tangential Coordinates. Proceeding to University of Chicago, he studied number theory and Waring's problem under L. E. Dickson. In 1932 he was a awarded a Ph.D. on the strength of his dissertation Analytical Investigations of Waring's Theorem. He continued post-graduate study, first with E. T. Bell at California Institute of Technology, then in 1934 with G. H. Hardy at Cambridge University. He published in the Transactions of the American Mathematical Society and extended some work of Viggo Brun in 1938.
Ralph James was a professor of mathematics at University of California, Berkeley from 1934 to 1939. He was then called to University of Saskatchewan where he became Head of the mathematics department. In 1943 he began his long tenure at University of British Columbia, becoming Head of the department in 1948. James made contributions to the theory of the Perron integral and to solution of Goldbach's conjecture.
Since 1978, the Canadian Mathematical Society have awarded the Coxeter–James Prize in his honor.
Papers
Ralph Duncan James published the following papers in the course of his career:
1934: Mathematische Annalen "On the representation of integers as sums of pyramidal numbers"
1934: Transactions of the American Mathematical Society 36(2):395–444 "The value of the number g(k) in Waring's problem"
1938: Transactions of the American Mathematical Society 43(2):296–302 "A problem in additive number theory"
1939: Duke Mathematical Journal 5:948–62 "Integers which are not represented by certain ternary qu |
https://en.wikipedia.org/wiki/Centre%20for%20Food%20Safety | Centre for Food Safety (CFS; ) is the food safety authority of the Hong Kong government. Its mission is to ensure food is safe and fit for consumption through tripartite collaboration among the government, food trade, and consumers. The CFS was created in May 2006 under the Food and Environmental Hygiene Department of the Environment and Ecology Bureau.
History
Plans to form a separate agency to specifically tackle food safety were proposed in 2005, following multiple food safety incidents including an outbreak of Streptococcus suis and freshwater fish contaminated with malachite green. At its initial conception, the centre was expected to take a similar structure as the Centre for Health Protection, and bring together experts from various fields to tackle food safety issues.
A proposal for the centre was rejected by the Legislative Council on 18 January 2006, citing concerns of marginalising veterinarians and lacking clarity.
Within the first months after the centre is set up, legislators complained that the centre had been doing too little to effective control food safety in Hong Kong.
Logo
The department's orange colour is adopted in the Centre logo plus the green colour representing "safety and hope". The letters 'C', 'F' and 'S' are abbreviation for Centre for Food Safety. |
https://en.wikipedia.org/wiki/Master%20of%20Monsters%20%28video%20game%29 | Master of Monsters is a turn-based strategy game developed by SystemSoft for the MSX and NEC PC8801. It was ported to a variety of consoles and PCs including the PC Engine CD, NEC PC9801, and Sega Genesis/Mega Drive. While it never had the same success as its SystemSoft stablemate Daisenryaku, the game garnered a loyal following. Its success in the North American market on the Sega Genesis proved sufficient for a sequel on the Sega Saturn, and an anime art-style enhanced Sony PlayStation version titled Disciples of Gaia with a Japanese role-playing game feel. Master of Monsters: Disciples of Gaia was released in 1998.
Gameplay
Gameplay engages players by permitting them to summon and move monsters around a board in an effort to capture towers and to eventually defeat the opponents (which are controlled either by other humans or by the computer program). Moves are based on a hexagonal board structure, such that every tile on the board is adjacent to six other tiles. Other notable features were the large variety of monsters, upgrading ("leveling up") of veteran units and control of a "Master" character who, if killed, can end the game for that player.
The focus of the game is strategic, despite the fantasy-type characters that might imply an RPG element. Other than the existence of the Master character and magic in the game, the gameplay is very similar to System Soft's more hardcore modern warfare strategic wargame series Daisenryaku, with the exception that some versions of the Master of Monsters (such as Master of Monsters – Final) series allow equippable items, weapons and armor.
Comparisons
The later Lords of Chaos by Julian Gollop of Mythos Games shares many of the same elements of summoning and tactics, along with the earlier title Chaos from 1985. David White, creator of the open-source turn-based strategy game The Battle for Wesnoth, cited Master of Monsters as an inspiration. Master of Monsters was also compared to later games such as the role-playing |
https://en.wikipedia.org/wiki/Neanderthal%20extinction | Neanderthals became extinct around 40,000 years ago. Hypotheses on the causes of the extinction include violence, transmission of diseases from modern humans which Neanderthals had no immunity to, competitive replacement, extinction by interbreeding with early modern human populations, natural catastrophes, climate change and inbreeding depression. It is likely that multiple factors caused the demise of an already low population.
Possible coexistence before extinction
In research published in Nature in 2014, an analysis of radiocarbon dates from forty Neanderthal sites from Spain to Russia found that the Neanderthals disappeared in Europe between 41,000 and 39,000 years ago with 95% probability. The study also found with the same probability that modern humans and Neanderthals overlapped in Europe for between 2,600 and 5,400 years. Modern humans reached Europe between 45,000 and 43,000 years ago. Improved radiocarbon dating published in 2015 indicates that Neanderthals disappeared around 40,000 years ago, which overturns older carbon dating which indicated that Neanderthals may have lived as recently as 24,000 years ago, including in refugia on the south coast of the Iberian peninsula such as Gorham's Cave.
Zilhão et al. (2017) argue for pushing this date forward by some 3,000 years, to 37,000 years ago.
Inter-stratification of Neanderthal and modern human remains has been suggested, but is disputed. Stone tools that have been proposed to be linked to Neanderthals have been found at Byzovya (:ru:Бызовая) in the polar Urals, and dated to 31,000 to 34,000 years ago, but is also disputed.
Possible cause of extinction
Violence
Kwang Hyun Ho discusses the possibility that Neanderthal extinction was either precipitated or hastened by violent conflict with Homo sapiens. Violence in early hunter-gatherer societies usually occurred as a result of resource competition following natural disasters. It is therefore plausible to suggest that violence, including primitive wa |
https://en.wikipedia.org/wiki/Multiscale%20geometric%20analysis | Multiscale geometric analysis or geometric multiscale analysis is an emerging area of high-dimensional signal processing and data analysis.
See also
Wavelet
Scale space
Multi-scale approaches
Multiresolution analysis
Singular value decomposition
Compressed sensing
Further reading
Signal processing
Spatial analysis |
https://en.wikipedia.org/wiki/%CE%95-net%20%28computational%20geometry%29 | In computational geometry, an ε-net (pronounced epsilon-net) is the approximation of a general set by a collection of simpler subsets. In probability theory it is the approximation of one probability distribution by another.
Background
Let X be a set and R be a set of subsets of X; such a pair is called a range space or hypergraph, and the elements of R are called ranges or hyperedges. An ε-net of a subset P of X is a subset N of P such that any range r ∈ R with |r ∩ P| ≥ ε|P| intersects N. In other words, any range that intersects at least a proportion ε of the elements of P must also intersect the ε-net N.
For example, suppose X is the set of points in the two-dimensional plane, R is the set of closed filled rectangles (products of closed intervals), and P is the unit square [0, 1] × [0, 1]. Then the set N consisting of the 8 points shown in the adjacent diagram is a 1/4-net of P, because any closed filled rectangle intersecting at least 1/4 of the unit square must intersect one of these points. In fact, any (axis-parallel) square, regardless of size, will have a similar 8-point 1/4-net.
For any range space with finite VC dimension d, regardless of the choice of P, there exists an ε-net of P of size
because the size of this set is independent of P, any set P can be described using a set of fixed size.
This facilitates the development of efficient approximation algorithms. For example, suppose we wish to estimate an upper bound on the area of a given region, that falls inside a particular rectangle P. One can estimate this to within an additive factor of ε times the area of P by first finding an ε-net of P, counting the proportion of elements in the ε-net falling inside the region with respect to the rectangle P, and then multiplying by the area of P. The runtime of the algorithm depends only on ε and not P. One straightforward way to compute an ε-net with high probability is to take a sufficient number of random points, where the number of random points |
https://en.wikipedia.org/wiki/Graphical%20Data%20Display%20Manager | GDDM (Graphical Data Display Manager) is a computer graphics system for the IBM System/370 which was developed in IBM's Hursley lab, and first released in 1979. GDDM was originally designed to provide programming support for the IBM 3279 colour display terminal and the associated 3287 colour printer. The 3279 was a colour graphics terminal designed to be used in a general business environment.
GDDM was extended in the early 1980s to provide graphics support for all of IBM's display terminals and printers, and ran on all of IBM's mainframe operating systems.
GDDM also provided support for the (then current) international standards for interactive computer graphics: GKS and PHIGS. Both GKS and PHIGS were designed around the requirements of CAD systems.
GDDM is also available on the IBM i midrange operating system, as well as its predecessor, the AS/400.
GDDM comprises a number of components:
Graphics primitives - lines, circles, boxes etc.
Graphing - through the Presentation Graphics Feature (PGF)
Language support - PL/I, REXX, COBOL etc.
Conversion capabilities - for example to GIF format.
Interactive Chart Utility (ICU).
GDDM remains in widespread use today, embedded in many z/OS applications, as well as in system programs.
GDDM and OS/2 Presentation Manager
IBM and Microsoft began collaborating on the design of OS/2 in 1986. The Graphics Presentation Interface (GPI), the graphics API in the OS/2 Presentation Manager, was based on IBM's GDDM and the Graphics Control Program (GCP). GCP was originally developed in Hursley for the 3270/PC-G and 3270/PC-GX terminals.
The GPI was the primary graphics API for the OS/2 operating system.
At the time (1980s), the graphical user interface (GUI) was still in its early stages of popularity, but already it was clear that the foundation of a good GUI was a graphics API with strong real-time interactive capabilities. Unfortunately, the design of GDDM was closer to (at the time) traditional graphics APIs like GKS, wh |
https://en.wikipedia.org/wiki/Software%20law | Software law refers to the legal remedies available to protect software-based assets. Software may, under various circumstances and in various countries, be restricted by patent or copyright or both. Most commercial software is sold under some kind of software license agreement.
See also
Legal aspects of computing
Software copyright
Software patent
Software license
Software license agreement
Proprietary software
Free and open source software |
https://en.wikipedia.org/wiki/Loss%20reserving | Loss reserving is the calculation of the required reserves for a tranche of insurance business, including outstanding claims reserves.
Typically, the claims reserves represent the money which should be held by the insurer so as to be able to meet all future claims arising from policies currently in force and policies written in the past.
Methods of calculating reserves in general insurance are different from those used in life insurance, pensions and health insurance since general insurance contracts are typically of a much shorter duration. Most general insurance contracts are written for a period of one year, and typically there is only one payment of premium at the start of the contract in exchange for coverage over the year. Reserves are calculated differently from contracts of a longer duration with multiple premium payments since there are no future premiums to consider in this case. The reserves are calculated by forecasting future losses from past losses.
Methods
The most popular methods of claims reserving include the chain-ladder method and the Bornhuetter–Ferguson method.
Another method is frequency-severity approach, used mainly when data is sparse.
The chain-ladder method, also known as the development method, assumes that past experience is an indicator of future experience. Loss development patterns in the past are used to estimate how claim amounts will increase (or decrease) in the future.
The Bornhuetter–Ferguson method uses both past loss development as well as an independently derived prior estimate of ultimate expected losses.
Outstanding claims reserves
Outstanding claims reserves in general insurance are a type of technical reserve or accounting provision in the financial statements of an insurer. They seek to quantify the loss liabilities for insurance claims which have been reported and not yet settled
(RBNS) or which have been incurred but not yet reported (IBNR) reserves. This is a technical reserve of an insurance company, and is es |
https://en.wikipedia.org/wiki/Rise%20and%20Resurrection%20of%20the%20American%20Programmer | Rise and Resurrection of the American Programmer is a book written by Edward Yourdon in 1996. It is the sequel to Decline and Fall of the American Programmer. In the original, written at the beginning of the 1990s, Yourdon warned American programmers that their business was not sustainable against foreign competition. By the middle of the decade Microsoft had released Windows 95, which marked a groundbreaking new direction for the operating system, the internet was beginning to rise as a serious consumer marketplace, and the Java software platform had made its first public release.
Due to such large changes in the state of the software industry, Yourdon reversed some of his original predictions. Notably absent from the book is any significant consideration of the open source software movement, particularly the development of the Linux kernel and the GNU operating system, which would come to have increasing significance in the coming decade in shaping the software industry. Both the internet, Microsoft's business strategy, and Java, which all feature significantly in Yourdon's thesis, would come to be heavily influenced by this phenomenon.
1996 non-fiction books
Software development books
Software quality
Software industry
Science and technology in the United States
Prentice Hall books |
https://en.wikipedia.org/wiki/Creamery | A creamery is a place where milk and cream are processed and where butter and cheese is produced. Cream is separated from whole milk; pasteurization is done to the skimmed milk and cream separately. Whole milk for sale has had some cream returned to the skimmed milk.
The creamery is the source of butter from a dairy. Cream is an emulsion of fat-in-water; the process of churning causes a phase inversion to butter which is an emulsion of water-in-fat. Excess liquid as buttermilk is drained off in the process. Modern creameries are automatically controlled industries, but the traditional creamery needed skilled workers. Traditional tools included the butter churn and Scotch hands.
The term "creamery" is sometimes used in retail trade as a place to buy milk products such as yogurt and ice cream. Under the banner of a creamery one might find a store also stocking pies and cakes or even a coffeehouse with confectionery.
See also
List of cheesemakers
List of dairy products |
https://en.wikipedia.org/wiki/Agarose%20gel%20electrophoresis | Agarose gel electrophoresis is a method of gel electrophoresis used in biochemistry, molecular biology, genetics, and clinical chemistry to separate a mixed population of macromolecules such as DNA or proteins in a matrix of agarose, one of the two main components of agar. The proteins may be separated by charge and/or size (isoelectric focusing agarose electrophoresis is essentially size independent), and the DNA and RNA fragments by length. Biomolecules are separated by applying an electric field to move the charged molecules through an agarose matrix, and the biomolecules are separated by size in the agarose gel matrix.
Agarose gel is easy to cast, has relatively fewer charged groups, and is particularly suitable for separating DNA of size range most often encountered in laboratories, which accounts for the popularity of its use. The separated DNA may be viewed with stain, most commonly under UV light, and the DNA fragments can be extracted from the gel with relative ease. Most agarose gels used are between 0.7–2% dissolved in a suitable electrophoresis buffer.
Properties of agarose gel
Agarose gel is a three-dimensional matrix formed of helical agarose molecules in supercoiled bundles that are aggregated into three-dimensional structures with channels and pores through which biomolecules can pass. The 3-D structure is held together with hydrogen bonds and can therefore be disrupted by heating back to a liquid state. The melting temperature is different from the gelling temperature, depending on the sources, agarose gel has a gelling temperature of 35–42 °C and a melting temperature of 85–95 °C. Low-melting and low-gelling agaroses made through chemical modifications are also available.
Agarose gel has large pore size and good gel strength, making it suitable as an anticonvection medium for the electrophoresis of DNA and large protein molecules. The pore size of a 1% gel has been estimated from 100 nm to 200–500 nm, and its gel strength allows gels as dilute |
https://en.wikipedia.org/wiki/Motzkin%E2%80%93Taussky%20theorem | The Motzkin–Taussky theorem is a result from operator and matrix theory about the representation of a sum of two bounded, linear operators (resp. matrices). The theorem was proven by Theodore Motzkin and Olga Taussky-Todd.
The theorem is used in perturbation theory, where e.g. operators of the form
are examined.
Statement
Let be a finite-dimensional complex vector space. Furthermore, let be such that all linear combinations
are diagonalizable for all . Then all eigenvalues of are of the form
(i.e. they are linear in und ) and are independent of the choice of .
Here stands for an eigenvalue of .
Comments
Motzkin and Taussky call the above property of the linearity of the eigenvalues in property L.
Bibliography
Kato, Tosio (1995). Perturbation Theory for Linear Operators. Berlin, Heidelberg: Springer. p. 86. ISBN 978-3-540-58661-6, doi:10.1007/978-3-642-66282-9.
Friedland, Shmuel (1981). A generalization of the Motzkin-Taussky theorem. Linear Algebra and its Applications. Vol. 36. pp. 103–109. doi:10.1016/0024-3795(81)90223-8.
Notes
Mathematical theorems
Linear algebra
Perturbation theory
Linear operators |
https://en.wikipedia.org/wiki/Pythagorean%20theorem | In mathematics, the Pythagorean theorem or Pythagoras' theorem is a fundamental relation in Euclidean geometry between the three sides of a right triangle. It states that the area of the square whose side is the hypotenuse (the side opposite the right angle) is equal to the sum of the areas of the squares on the other two sides.
The theorem can be written as an equation relating the lengths of the sides a, b and the hypotenuse c, sometimes called the Pythagorean equation:
The theorem is named for the Greek philosopher Pythagoras, born around 570 BC. The theorem has been proved numerous times by many different methods – possibly the most for any mathematical theorem. The proofs are diverse, including both geometric proofs and algebraic proofs, with some dating back thousands of years.
When Euclidean space is represented by a Cartesian coordinate system in analytic geometry, Euclidean distance satisfies the Pythagorean relation: the squared distance between two points equals the sum of squares of the difference in each coordinate between the points.
The theorem can be generalized in various ways: to higher-dimensional spaces, to spaces that are not Euclidean, to objects that are not right triangles, and to objects that are not triangles at all but n-dimensional solids. The Pythagorean theorem has attracted interest outside mathematics as a symbol of mathematical abstruseness, mystique, or intellectual power; popular references in literature, plays, musicals, songs, stamps, and cartoons abound.
Proofs using constructed squares
Rearrangement proofs
In one rearrangement proof, two squares are used whose sides have a measure of and which contain four right triangles whose sides are a, b and c, with the hypotenuse being c. In the square on the right side, the triangles are placed such that the corners of the square correspond to the corners of the right angle in the triangles, forming a square in the center whose sides are length c. Each outer square has an ar |
https://en.wikipedia.org/wiki/Golo%20%28programming%20language%29 | Golo is computer software, a programming language for the Java virtual machine (JVM). It is simple, with dynamic, weak typing. It was created in 2012 as part of the research activities of the DynaMid group of the Centre of Innovation in Telecommunications and Integration of service (CITI) Laboratory at Institut national des sciences appliquées de Lyon (INSA). It is distributed as free and open-source software under the Eclipse Public License 2.0.
History
It has been built as a showcase on how to build a language runtime with invokedynamic. Golo is largely interoperable with the programming language Java and other JVM languages (e.g., numeric types are boxing classes from java.lang, and collection literals leverage java.util classes), that runs on the JVM.
In June 2015, Golo became an official Eclipse Foundation project. The project was terminated in September 2022.
Technical details
The language features have been initially designed around the abilities of invokedynamic – JSR 292 that appeared in Java SE 7. Golo uses ahead-of-time compilation of bytecode. While the bytecode remains stable over a program execution, the invokedynamic-based reconfigurable call sites support the adaptive dispatch mechanisms put in place for helping the HotSpot just-in-time compiler (JIT) to extract reasonable performance.
Publications
Baptiste Maingret, Frédéric Le Mouël, Julien Ponge, Nicolas Stouls, Jian Cia and Yannick Loiseau. Towards a Decoupled Context-Oriented Programming Language for the Internet of Things. To appear in the 7th International Workshop on Context-Oriented Programming hosted at ECOOP 2015. Prague, Czech Republic. July 2015.
Julien Ponge, Frédéric Le Mouël, Nicolas Stouls, Yannick Loiseau. Opportunities for a Truffle-based Golo Interpreter. Technical report arXiv:1505.06003 (cs.PL) and HAL-INRIA deposit
Julien Ponge, Frédéric Le Mouël and Nicolas Stouls. Golo, a Dynamic, Light and Efficient Language for Post-Invokedynamic JVM. In Procs. of PPPJ'13. Stuttga |
https://en.wikipedia.org/wiki/Descriptional%20Complexity%20of%20Formal%20Systems | DCFS, the International Workshop on Descriptional Complexity of Formal Systems is an annual academic conference in the
field of computer science.
Beginning with the 2011 edition, the proceedings of the workshop appear in the series Lecture Notes in Computer Science. Already since the very beginning, extended versions of selected papers are published as special issues of the International Journal of Foundations of Computer Science, the Journal of Automata, Languages and Combinatorics, of Theoretical Computer Science, and of Information and Computation In 2002 DCFS was the result of the merger of the workshops DCAGRS (Descriptional Complexity of Automata, Grammars and Related Structures) and FDSR (Formal Descriptions and Software Reliability). The workshop is often collocated with international conferences in related fields, such as ICALP, DLT and CIAA.
Topics of the workshop
Typical topics include:
various measures of descriptional complexity of automata, grammars, languages and of related systems
trade-offs between descriptional complexity and mode of operation
circuit complexity of Boolean functions and related measures
succinctness of description of (finite) objects
state complexity of finite automata
descriptional complexity in resource-bounded or structure-bounded environments
structural complexity
descriptional complexity of formal systems for applications (e.g. software reliability, software and hardware testing, modelling of natural languages)
descriptional complexity aspects of nature-motivated (bio-inspired) architectures and unconventional models of computing
Kolmogorov–Chaitin complexity and descriptional complexity
As such, the topics of the conference overlap with those of the International Federation for Information Processing Working Group 1.2 on descriptional complexity.
Significance
In a survey on descriptional complexity, state that "since more than a decade the Workshop on 'Descriptional Complexity of Formal Systems' (DCFS), [...] |
https://en.wikipedia.org/wiki/Digital%20buffer | A digital buffer (or a voltage buffer) is an electronic circuit element used to isolate an input from an output. The buffer's output state mirrors the input state. The buffer's input impedance is high. It draws little current, to avoid disturbing the input circuit. Also called a unity gain buffer, a digital buffer does not intentionally amplify or attenuate the input signal.
The digital buffer is important in data transmission, translating voltage pulses between connected systems. Buffers are used in registers (data storage device) and buses (data transferring device). A tri-state digital buffer can connect a device to a digital bus. The tri-state buffer's output is either high, low, or disconnected.
Functionality
A digital buffer transfers a voltage from a high output impedance circuit to a second circuit with low input impedance. Directly connecting a low impedance load to a power source draws current according to Ohm's law. The high current affects the source. Digital buffer inputs are high impedance. A buffered load effectively does not affect the source circuit. The buffer's output current is generated within the buffer. In this way, a buffer provides isolation between a power source and a low impedance input.
Types
Single input voltage buffer
Inverting buffer
This buffer's output state is the opposite of the input state. If the input is high, the output is low, and vice versa. Graphically, an inverting buffer is represented by a triangle with a small circle at the output, with the circle signifying inversion. The inverter is a basic building block in digital electronics. Decoders, state machines, and other sophisticated digital devices often include inverters.
Non-inverting buffer
This kind of buffer performs no inversion or decision-making possibilities. A single input digital buffer is different from an inverter. It does not invert or alter its input signal in any way. It reads an input and outputs a value. Usually, the input side reads either HIGH |
https://en.wikipedia.org/wiki/Gallon%20per%20watt-hour | The gallon per watt-hour or (G/Wh) is a formula used to test the efficiency of a pool pump or sump pump.
California Title 20
California's Appliance Efficiency Regulations were established in 1976 in response to a legislative mandate to reduce California's energy consumption. Through that "Title 20" was born.
Over time with the increase of pools and their complexity, the potential energy savings from residential pool pumps has become huge.
Residential pool pumps were first included in the 2005 Title-20 appliance standards that were adopted at the end of 2005.
California has a limited ability to produce electricity. When California electrical demand exceeds its production capacity the utility companies must purchase electricity, usually form out of state companies at a much higher cost. The cost of building power plants and the environmental issues they bring make it difficult to build power plants quick enough to keep up with California's energy needs. This makes conservation the most feasible and economical solution for the utility companies.
There are approximately 1.5 million pools in California that consume an average of 2,000 watts when running. Those 2,000 watts can be reduced by controlling the size and performance of the pool and spa filter pump.
How it's calculated
G/Wh makes it easy for homeowners and plumbing professionals to quickly determine the energy efficiency of a pump. Simply stated G/Wh links efficiency and performance by illustrating how many gallons of water are pumped using one watt hour of electricity.
To calculate G/Wh, take the gallons per hour (GPH) pumped, divided by the power the pump consumes in watts. GPH/W = G/Wh
California Title 24
California Code of Regulations (CCR), Title 24, also known as the California Building Standards Code, is a compilation of three types of building standards from three different origins:
Building standards that have been adopted by state agencies without change from building standards contained in |
https://en.wikipedia.org/wiki/Nibrin | Nibrin, also known as NBN or NBS1, is a protein which in humans is encoded by the NBN gene.
Function
Nibrin is a protein associated with the repair of double strand breaks (DSBs) which pose serious damage to a genome. It is a 754 amino acid protein identified as a member of the NBS1/hMre11/RAD50(N/M/R, more commonly referred to as MRN) double strand DNA break repair complex. This complex recognizes DNA damage and rapidly relocates to DSB sites and forms nuclear foci. It also has a role in regulation of N/M/R (MRN) protein complex activity which includes end-processing of both physiological and mutagenic DNA double strand breaks (DSBs).
Cellular response to DSBs
Cellular response is performed by damage sensors, effectors of lesion repair and signal transduction. The central role is carried out by ataxia telangiectasia mutated (ATM) by activating the DSB signaling cascade, phosphorylating downstream substrates such as histone H2AX and NBS1. NBS1 relocates to DSB sites by interaction of FHA/BRCT domains with phosphorylated histone H2AX. Once it interacts with nibrin c-terminal hMre11-binding domain, hMre11 and hRad50 relocate from the cytoplasm to the nucleus then to sites of DSBs. They finally relocate to N/M/R where they form the foci at the site of damage.
Double strand breaks (DSBs)
DSBs occur during V(D)J recombination during early B and T cell development. This is at the point when the cells of the immune system are developing and the DSBs affect the development of lymphoid cells. DSBs also occur in immunoglobulin class switch in mature B cells. More frequently, however, DSBs are caused by mutagenic agents like radiomimetic chemicals and ionizing radiation(IR).
DSB mutations
As mentioned, DSBs cause extreme damage to DNA. Mutations that cause defective repair of DSBs tend to accumulate un-repaired DSBs. One such mutation is associated with Nijmegen breakage syndrome (NBS), a radiation hyper-sensitive disease. It is a rare inherited autosomal |
https://en.wikipedia.org/wiki/Auxiliary%20power%20unit | An auxiliary power unit (APU) is a device on a vehicle that provides energy for functions other than propulsion. They are commonly found on large aircraft and naval ships as well as some large land vehicles. Aircraft APUs generally produce 115 V AC voltage at 400 Hz (rather than 50/60 Hz in mains supply), to run the electrical systems of the aircraft; others can produce 28 V DC voltage. APUs can provide power through single or three-phase systems.
Transport aircraft
History
During World War I, the British Coastal class blimps, one of several types of airship operated by the Royal Navy, carried a ABC auxiliary engine. These powered a generator for the craft's radio transmitter and, in an emergency, could power an auxiliary air blower. One of the first military fixed-wing aircraft to use an APU was the British, World War 1, Supermarine Nighthawk, an anti-Zeppelin night fighter.
During World War II, a number of large American military aircraft were fitted with APUs. These were typically known as putt–putts, even in official training documents. The putt-putt on the B-29 Superfortress bomber was fitted in the unpressurised section at the rear of the aircraft. Various models of four-stroke, Flat-twin or V-twin engines were used. The engine drove a P2, DC generator, rated 28.5 Volts and 200 Amps (several of the same P2 generators, driven by the main engines, were the B-29's DC power source in flight). The putt-putt provided power for starting the main engines and was used after take-off to a height of . The putt-putt was restarted when the B-29 was descending to land.
Some models of the B-24 Liberator had a putt–putt fitted at the front of the aircraft, inside the nose-wheel compartment. Some models of the Douglas C-47 Skytrain transport aircraft carried a putt-putt under the cockpit floor.
As mechanical "startup" APUs for jet engines
The first German jet engines built during the Second World War used a mechanical APU starting system designed by the German engineer |
https://en.wikipedia.org/wiki/GABRQ | Gamma-aminobutyric acid receptor subunit theta is a protein that in humans is encoded by the GABRQ gene. The protein encoded by this gene is a subunit of the GABAA receptor.
The θ subunit has highest sequence similarity with the β1 subunit. This subunit coassembles with:
α2, β1, and γ1
α3 and β1
α3, β1, and ε. |
https://en.wikipedia.org/wiki/Klinefelter%20syndrome | Klinefelter syndrome (KS), also known as 47,XXY, is an aneuploid genetic condition where a male has an additional copy of the X chromosome. The primary features are infertility and small, poorly functioning testicles. Usually, symptoms are subtle and subjects do not realize they are affected. Sometimes, symptoms are more evident and may include weaker muscles, greater height, poor motor coordination, less body hair, breast growth, and less interest in sex. Often, these symptoms are noticed only at puberty. Intelligence is usually average, but reading difficulties and problems with speech are more common.
Klinefelter syndrome occurs randomly. The extra X chromosome comes from the father and mother nearly equally. An older mother may have a slightly increased risk of a child with KS. The syndrome is defined by the presence of at least one extra X chromosome in addition to a Y chromosome yielding a total of 47 or more chromosomes rather than the usual 46. KS is diagnosed by the genetic test known as a karyotype.
While no cure is known, a number of treatments may help. Physical therapy, occupational therapy, speech and language therapy, counselling, and adjustments of teaching methods may be useful. Testosterone replacement may be used in those who have significantly lower levels. Enlarged breasts may be removed by surgery. Approximately half of affected males have a chance of fathering children with the help of assisted reproductive technology, but this is expensive and not risk free. XXY males have a ~15-fold higher risk of developing breast cancer than typical males, but still lower than that of females. People with the condition have a nearly normal life expectancy.
Klinefelter syndrome is one of the most common chromosomal disorders, occurring in one to two per 1,000 live male births. It is named after American endocrinologist Harry Klinefelter, who identified the condition in the 1940s. In 1956, the extra X chromosome was identified as the cause. Mice can als |
https://en.wikipedia.org/wiki/Hypoxanthine | Hypoxanthine is a naturally occurring purine derivative. It is occasionally found as a constituent of nucleic acids, where it is present in the anticodon of tRNA in the form of its nucleoside inosine. It has a tautomer known as 6-hydroxypurine. Hypoxanthine is a necessary additive in certain cells, bacteria, and parasite cultures as a substrate and nitrogen source. For example, it is commonly a required reagent in malaria parasite cultures, since Plasmodium falciparum requires a source of hypoxanthine for nucleic acid synthesis and energy metabolism.
In August 2011, a report, based on NASA studies with meteorites found on Earth, was published suggesting hypoxanthine and related organic molecules, including the DNA and RNA components adenine and guanine, may have been formed extraterrestrially in outer space.
The Pheretima aspergillum worm, used in Chinese medicine preparations, contains hypoxanthine.
Reactions
It is one of the products of the action of xanthine oxidase on xanthine. However, more frequently in purine degradation, xanthine is formed from oxidation of hypoxanthine by xanthine oxidoreductase.
Hypoxanthine-guanine phosphoribosyltransferase converts hypoxanthine into IMP in nucleotide salvage.
Hypoxanthine is also a spontaneous deamination product of adenine. Because of its resemblance to guanine, the spontaneous deamination of adenine can lead to an error in DNA transcription/replication, as it base pairs with cytosine. Hypoxanthine is removed from DNA by base excision repair, initiated by N-methylpurine glycosylase (MPG), also known as alkyl adenine glycosylase (Aag).
Additional images |
https://en.wikipedia.org/wiki/Meglumine%20antimoniate | Meglumine antimoniate is a medicine used to treat leishmaniasis. This includes visceral, mucocutaneous, and cutaneous leishmaniasis. It is given by injection into a muscle or into the area infected.
Side effects include loss of appetite, nausea, abdominal pain, cough, feeling tired, muscle pain, irregular heartbeat, and kidney problems. It should not be used in people with significant heart, liver, or kidney problems. It is not recommended during breastfeeding. It belongs to a group of medications known as the pentavalent antimonials.
Meglumine antimoniate came into medical use in 1946. It is on the World Health Organization's List of Essential Medicines. It is available in Southern Europe and Latin America but not the United States.
Society and culture
It is manufactured by Aventis and sold as Glucantime in France, and Glucantim in Italy.
See also
Meglumine |
https://en.wikipedia.org/wiki/Victor%20Andreevich%20Toponogov | Victor Andreevich Toponogov (; March 6, 1930 – November 21, 2004) was an outstanding Russian mathematician, noted for his contributions to differential geometry and so-called Riemannian geometry "in the large".
Biography
After finishing secondary school in 1948, Toponogov entered the department of Mechanics and Mathematics at Tomsk State University, graduated with honours in 1953, and continued as a graduate student there until 1956. He moved to an institution in Novosibirsk in 1956 and lived in that city for the rest of his career. Since the institution at Novosibirsk had not yet been fully credentialed, he had defended his Ph.D. thesis at Moscow State University in 1958, on a subject in Riemann spaces. Novosibirsk State University was established in 1959. In 1961 Toponogov became a professor at a newly created Institute of Mathematics and Computing in Novosibirsk affiliated with the state university.
Toponogov's scientific interests were influenced by his advisor Abram Fet, who taught at Tomsk and later at Novosibirsk. Fet was a well-recognized topologist and specialist in variational calculus in the large. Toponogov's work was also strongly influenced by the work of Aleksandr Danilovich Aleksandrov. Later, the class of metric spaces known as CAT(k) spaces would be named after Élie Cartan, Aleksandrov and Toponogov.
Toponogov published over forty papers and some books during his career. His works are concentrated in Riemannian geometry "in the large". A significant number of his students also made notable contributions in this field.
Conjecture on Complete Convex Surfaces
In 1995 Toponogov made the conjecture:
On a complete convex surface S homeomorphic to a plane the following equality holds:
where and are the principal curvatures of S.
In words, it states that every complete convex surface homeomorphic to a plane must have an umbilic point which may lie at infinity. As such, it is the natural open analog of the Carathéodory conjecture for closed conve |
https://en.wikipedia.org/wiki/Plurisubharmonic%20function | In mathematics, plurisubharmonic functions (sometimes abbreviated as psh, plsh, or plush functions) form an important class of functions used in complex analysis. On a Kähler manifold, plurisubharmonic functions form a subset of the subharmonic functions. However, unlike subharmonic functions (which are defined on a Riemannian manifold) plurisubharmonic functions can be defined in full generality on complex analytic spaces.
Formal definition
A function
with domain
is called plurisubharmonic if it is upper semi-continuous, and for every complex line
with
the function is a subharmonic function on the set
In full generality, the notion can be defined on an arbitrary complex manifold or even a complex analytic space as follows. An upper semi-continuous function
is said to be plurisubharmonic if and only if for any holomorphic map
the function
is subharmonic, where denotes the unit disk.
Differentiable plurisubharmonic functions
If is of (differentiability) class , then is plurisubharmonic if and only if the hermitian matrix , called Levi matrix, with
entries
is positive semidefinite.
Equivalently, a -function f is plurisubharmonic if and only if is a positive (1,1)-form.
Examples
Relation to Kähler manifold: On n-dimensional complex Euclidean space , is plurisubharmonic. In fact, is equal to the standard Kähler form on up to constant multiples. More generally, if satisfies
for some Kähler form , then is plurisubharmonic, which is called Kähler potential. These can be readily generated by applying the ddbar lemma to Kähler forms on a Kähler manifold.
Relation to Dirac Delta: On 1-dimensional complex Euclidean space , is plurisubharmonic. If is a C∞-class function with compact support, then Cauchy integral formula says
which can be modified to
.
It is nothing but Dirac measure at the origin 0 .
More Examples
If is an analytic function on an open set, then is plurisubharmonic on that open set.
Convex functions are plurisubh |
https://en.wikipedia.org/wiki/TetGen | TetGen is a mesh generator developed by Hang Si which is designed to partition any 3D geometry into tetrahedrons by employing a form of Delaunay triangulation whose algorithm was developed by the author.
TetGen has since been incorporated into other software packages such as Mathematica and Gmsh.
Some improvements by speed in quality in Version 1.6 were introduced.
See also
Gmsh
Salome (software) |
https://en.wikipedia.org/wiki/Chain%20of%20survival | The chain of survival refers to a series of actions that, properly executed, reduce the mortality associated with sudden cardiac arrest. Like any chain, the chain of survival is only as strong as its weakest link. The six interdependent links in the chain of survival are early recognition of sudden cardiac arrest and access to emergency medical care, early CPR, early defibrillation, early advanced cardiac life support, and physical and emotional recovery. The first three links in the chain can be performed by lay bystanders, while the second three links are designated to medical professionals. Currently, between 70 and 90% of cardiac arrest patients die before they reach the hospital. However, a cardiac arrest does not have to be lethal if bystanders can take the right steps immediately.
Background
According to the American Heart Association, out-of-hospital cardiac arrest can affect more than 300,000 people in the United States each year. Three minutes after the onset of cardiac arrest, a lack of blood flow starts to damage the brain, and 10 minutes after, the chances of survival are low. Therefore, bystanders have only a few minutes to act to optimize a person's chances of survival and recovery.
To improve survival outcomes for people who have experienced out-of-hospital cardiac arrest, the American Heart Association–International Liaison Committee on Resuscitation recommended the chain of survival concept in the early 2000s. Originally, the chain consisted of four steps: early access to emergency medical care was the first link, the second link was early CPR, early defibrillation was the third link, and the final link was early advanced cardiac life support. Over the years, the American Heart Association has added two new links to the chain: post-resuscitation care in 2010, and physical and emotional recovery in 2020. Also in 2020, the American Heart Association issued a new pediatric chain of survival for infants, children, and adolescents.
Mary M. Newman, |
https://en.wikipedia.org/wiki/Immunochemistry | Immunochemistry is the study of the chemistry of the immune system. This involves the study of the properties, functions, interactions and production of the chemical components (antibodies/immunoglobulins, toxin, epitopes of proteins like CD4, antitoxins, cytokines/chemokines, antigens) of the immune system. It also include immune responses and determination of immune materials/products by immunochemical assays.
In addition, immunochemistry is the study of the identities and functions of the components of the immune system. Immunochemistry is also used to describe the application of immune system components, in particular antibodies, to chemically labelled antigen molecules for visualization.
Various methods in immunochemistry have been developed and refined, and used in scientific study, from virology to molecular evolution. Immunochemical techniques include: enzyme-linked immunosorbent assay, immunoblotting (e.g., Western blot assay), precipitation and agglutination reactions, immunoelectrophoresis, immunophenotyping, immunochromatographic assay and cyflometry.
One of the earliest examples of immunochemistry is the Wasserman test to detect syphilis. Svante Arrhenius was also one of the pioneers in the field; he published Immunochemistry in 1907 which described the application of the methods of physical chemistry to the study of the theory of toxins and antitoxins.
Immunochemistry is also studied from the aspect of using antibodies to label epitopes of interest in cells (immunocytochemistry) or tissues (immunohistochemistry). |
https://en.wikipedia.org/wiki/Whyte%20notation | The Whyte notation is a classification method for steam locomotives, and some internal combustion locomotives and electric locomotives, by wheel arrangement. It was devised by Frederick Methvan Whyte, and came into use in the early twentieth century following a December 1900 editorial in American Engineer and Railroad Journal.
The notation was adopted and remains in use in North America and the United Kingdom to describe the wheel arrangements of steam locomotives, but for modern locomotives, multiple units and trams it has been supplanted by the UIC system in Europe and by the AAR system (essentially a simplification of the UIC system) in North America.
Structure of the system
Basic form
The notation in its basic form counts the number of leading wheels, then the number of driving wheels, and finally the number of trailing wheels, numbers being separated by dashes. For example, a locomotive with two leading axles (four wheels) in front, then three driving axles (six wheels) and then one trailing axle (two wheels) is classified as a locomotive, and is commonly known as a Pacific.
Denotion of other locomotives
Articulated locomotives
For articulated locomotives that have two wheelsets, such as Garratts, which are effectively two locomotives joined by a common boiler, each wheelset is denoted separately, with a plus sign (+) between them. Thus a "double Pacific" type Garratt is a . For Garratt locomotives, the plus sign is used even when there are no intermediate unpowered wheels, e.g. the LMS Garratt . This is because the two engine units are more than just power bogies. They are complete engines, carrying fuel and water tanks. The plus sign represents the bridge (carrying the boiler) that links the two engines.
Simpler articulated types, such as Mallets, have a jointed frame under a common boiler where there are no unpowered wheels between the sets of powered wheels. Typically, the forward frame is free to swing, whereas the rear frame is rigid with the bo |
https://en.wikipedia.org/wiki/Aprotinin | The drug aprotinin (Trasylol, previously Bayer and now Nordic Group pharmaceuticals), is a small protein bovine pancreatic trypsin inhibitor (BPTI), or basic trypsin inhibitor of bovine pancreas, which is an antifibrinolytic molecule that inhibits trypsin and related proteolytic enzymes. Under the trade name Trasylol, aprotinin was used as a medication administered by injection to reduce bleeding during complex surgery, such as heart and liver surgery. Its main effect is the slowing down of fibrinolysis, the process that leads to the breakdown of blood clots. The aim in its use was to decrease the need for blood transfusions during surgery, as well as end-organ damage due to hypotension (low blood pressure) as a result of marked blood loss. The drug was temporarily withdrawn worldwide in 2007 after studies suggested that its use increased the risk of complications or death; this was confirmed by follow-up studies. Trasylol sales were suspended in May 2008, except for very restricted research use. In February 2012 the European Medicines Agency (EMA) scientific committee reverted its previous standpoint regarding aprotinin, and has recommended that the suspension be lifted. Nordic became distributor of aprotinin in 2012.
Chemistry
Aprotinin is a monomeric (single-chain) globular polypeptide derived from bovine lung tissue. It has a molecular weight of 6512 Da and consists of 16 different amino acid types arranged in a chain 58 residues long that folds into a stable, compact tertiary structure of the 'small SS-rich" type, containing 3 disulfides, a twisted β-hairpin and a C-terminal α-helix.
The amino acid sequence for bovine BPTI is RPDFC LEPPY TGPCK ARIIR YFYNA KAGLC QTFVY GGCRA KRNNF KSAED CMRTC GGA. There are 10 positively charged lysine (K) and arginine (R) side chains and only 4 negative aspartate (D) and glutamates (E), making the protein strongly basic, which accounts for the basic in its name. (Because of the usual source organism, BPTI is sometimes refer |
https://en.wikipedia.org/wiki/Animal%20Crossing%20Plaza | Animal Crossing Plaza was a discontinued free to play social networking service developed and published by Nintendo for the Wii U. A spin-off of Animal Crossing: New Leaf of the Animal Crossing series, Plaza was released as a tie-in to Miiverse, Nintendo's now-defunct social networking service. The application is no longer actively supported by Nintendo, and was removed from the Nintendo eShop on December 22, 2014.
Gameplay
Animal Crossing Plaza allowed users to interact with other players of the Nintendo 3DS game Animal Crossing: New Leaf. The application was similar to Nintendo's Wara Wara Plaza, and allowed users to post messages for other players, receive news and updates about New Leaf, and participate in polls. The game connected with New Leaf via SD card, allowing players to post and archive New Leaf screenshots, and share in-game clothing designs using QR codes. Users could also upload Plaza posts directly to Nintendo's Miiverse social networking service. The game's overworld was populated by non-player characters from the Animal Crossing series, who users could interact with.
Development
Animal Crossing Plaza was announced in a Nintendo Direct on August 7, 2013, and was released digitally on the Nintendo eShop that same day. Plaza was planned as a limited-time application, with Nintendo stating in its announcement of the application that it would only be supported through the end of 2014.
On December 8, 2014, Nintendo released a statement confirming that it would cease ongoing support for Plaza. The application was removed from the Nintendo eShop on December 22, 2014, and the ability to create new posts within the application was removed on December 31, 2014. Plaza remains accessible to users who downloaded the application prior to its removal from eShop, though its social features are no longer usable. |
https://en.wikipedia.org/wiki/Mischa%20Dohler | Mischa Dohler is a Fellow of the Royal Academy of Engineering, Fellow of the Institute of Electrical and Electronics Engineers (IEEE) and Fellow of the Royal Society of Arts (RSA).
He was a Chair Professor of Wireless Communications at King's College London, where he worked on 6G and the Internet of Skills. He has been appointed to the Spectrum Advisory Board of Ofcom.
Career
He was a CTO at Worldsensing. He was a CTO at Sirius Insight. |
https://en.wikipedia.org/wiki/Ion%20transport%20number | In chemistry, ion transport number, also called the transference number, is the fraction of the total electric current carried in an electrolyte by a given ionic species :
Differences in transport number arise from differences in electrical mobility. For example, in an aqueous solution of sodium chloride, less than half of the current is carried by the positively charged sodium ions (cations) and more than half is carried by the negatively charged chloride ions (anions) because the chloride ions are able to move faster, i.e., chloride ions have higher mobility than sodium ions. The sum of the transport numbers for all of the ions in solution always equals unity:
The concept and measurement of transport number were introduced by Johann Wilhelm Hittorf in the year 1853. Liquid junction potential can arise from ions in a solution having different ion transport numbers.
At zero concentration, the limiting ion transport numbers may be expressed in terms of the limiting molar conductivities of the cation (), anion (), and electrolyte ():
and
where and are the numbers of cations and anions respectively per formula unit of electrolyte. In practice the molar ionic conductivities are calculated from the measured ion transport numbers and the total molar conductivity. For the cation , and similarly for the anion. In solutions, where ionic complexation or associaltion are important, two different tramsport/tramsference numbers can be defined.
The practical importance of high (i.e. close to 1) transference numbers of the charge-shuttling ion (i.e. Li+ in lithium-ion batteries) is related to the fact, that in single-ion devices (such as lithium-ion batteries) electrolytes with the transfer number of the ion near 1, concentration gradients do not develop. A constant electrolyte concentration is maintained during charge-discharge cycles. In case of porous electrodes a more complete utilization of solid electroactive materials at high current densities is possible, even |
https://en.wikipedia.org/wiki/Genetic%20Alliance | Genetic Alliance is a nonprofit organization, founded in 1986 by Joan O. Weiss, working with Victor A. McKusick, to advocate for health benefits in the accelerating field of genomic research. This organization is a network of over 1,000 disease advocacy organizations, universities, government organizations, private companies, and public policy organizations. They aim to advance genetic research agendas toward health benefit by engaging a broad range of stakeholders, including healthcare providers, researchers, industry professionals, public policy leaders, as well as individuals, families and communities. They create programs using a collaborative approach, and aim to increase efficiency and reduce obstacles in genetic research, while ensuring that voices from the involved disease communities are heard. They also promote public policies to advance healthcare. Genetic Alliance provides technical support and informational resources to guide disease-specific advocacy organizations in being their own research advocates. They also maintain a biobank as a central storage facility for several organizations who otherwise would not have the infrastructure to maintain their own repository.
History
The organization was founded in 1986 by Joan O. Weiss, working with Victor A. McKusick, to advocate for health benefits in the accelerating field of genomic research. The organisation is an umbrella organisation for a number of charities dealing with genetic diseases. The founding chair of the Genetic Alliance in 1989 was Ann Mercy Hunt who had founded the Tuberous Sclerosis Association.
Genetic Alliance Registry and Biobank
Genetic Alliance manages a biobank, the Genetic Alliance Registry and Biobank (GARB), which is a cooperatively-managed clinical data and tissue sample repository. GARB was established in 2003, and combines its standardized infrastructure with the interests and motivations of disease advocacy groups to develop effective diagnostic tools and treatments, to “ |
https://en.wikipedia.org/wiki/Allium%20oleraceum | Allium oleraceum, the field garlic, is a Eurasian species of wild onion. It is a bulbous perennial that grows wild in dry places, reaching in height. It reproduces by seed, bulbs and by the production of small bulblets in the flower head (similarly to Allium vineale). Unlike A. vineale, it is very rare with A. oleraceum to find flower-heads containing bulbils only. In addition, the spathe in A. oleraceum is in two parts.
Its specific epithet oleraceum means "vegetable/herbal" in Latin and is a form of ().
Description
Allium oleraceum grows to a height of about . The underground bulb is up to in diameter. The main stem is usually rounded, but is occasionally flattened, and bears two to four leaves and a terminal inflorescence composed of a number of small, stalked, pinkish-brown flowers and sometimes a few bulblets. The papery bracts have long points which often much overtop the flowers, the stamens of which do not protrude.
Distribution
Allium oleraceum is widespread across most of Europe, with additional populations in Turkey and the Caucasus. It is sparingly naturalised in scattered locations in North America.
In the United Kingdom, A. oleraceum is found in dry, grassy places, usually steeply sloping and calcareous soils, and on open sunny banks in river floodplains. A. oleraceum is scattered throughout England and very scattered in Wales, Scotland and Ireland. Erosion of coastal areas leads to a reduction in the available habitat for this species, leading to population declines. The highest altitude from which it has been recorded in Britain is in Dovedale, Derbyshire.
Allium oleraceum subsp. girerdii was formerly included, but is now classified as Allium oporinanthum.
See also
Allium vineale
Allium monanthum |
https://en.wikipedia.org/wiki/Flag%20of%20convenience | Flag of convenience (FOC) is a business practice whereby a ship's owners register a merchant ship in a ship register of a country other than that of the ship's owners, and the ship flies the civil ensign of that country, called the flag state. The term is often used pejoratively, and although common, the practice is sometimes regarded as contentious.
Each merchant ship is required by international law to be registered in a registry created by a country, and a ship is subject to the laws of that country, which are used also if the ship is involved in a case under admiralty law. A ship's owners may elect to register a ship in a foreign country so as to avoid the regulations of the owners' country, which may, for example, have stricter safety standards. They may also select a jurisdiction to reduce operating costs, avoiding higher taxes in the owners' country and bypassing laws that protect the wages and working conditions of mariners. The term "flag of convenience" has been used since the 1950s. A registry which does not have a nationality or residency requirement for ship registration is often described as an open registry. Panama, for example, offers advantages such as easier registration (often online), the ability to employ cheaper foreign labour, and an exemption on income taxes.
The modern practice of ships being registered in a foreign country began in the 1920s in the United States when shipowners seeking to serve alcohol to passengers during Prohibition registered their ships in Panama. Owners soon began to perceive advantages in terms of avoiding increased regulations and rising labor costs and continued to register their ships in Panama even after Prohibition ended. The use of open registries steadily increased, and in 1968, Liberia grew to surpass the United Kingdom with the world's largest ship register.
, more than half the world's merchant ships were registered with open registries, and almost 40% of the entire world fleet, in terms of deadweight t |
https://en.wikipedia.org/wiki/Graphisoft%20MEP%20Modeler | Graphisoft MEP Modeler (where MEP stands for Mechanical/Electrical/Plumbing) is an extension to Archicad, Graphisoft's architectural design tool to create three-dimensional models of ductwork, piping and electrical networks in order to make the building information model of the designed building more detailed an accurate.
Since Archicad is primarily used by architects, the building parts which are usually modeled in 3D with Archicad are walls, columns, slabs, roofs, etc. and some other objects like furniture. But when detailed plans are to be elaborated especially if the project is a medium or large-sized building, collision detection and constructibility are becoming more and more important in order to minimize design errors and unnecessary delays during construction. This is where MEP Modeler can help building engineers and architects to create a more detailed building model with ductworks and other HVAC systems modeled in 3D in order to achieve a better coordination between the different trades such as building engineers, structural engineers and architects.
Features
Graphisof MEP Modeler supports both the creation of MEP models from scratch — based on 2D plans provided by engineers — and the import of 3D data created with other MEP software products such as AutoCAD MEP or Revit MEP. The software provides three basic features:
MEP Toolbox is a set of dedicated tools (just like the Wall Tool or Window Tool) for modeling and editing ducts, pipes and other system components.
MEP Library is a library of parametric objects representing different parts of MEP systems with smart connections and other additional parameters needed for building engineering.
MEP Systems is a feature which helps the organization of various MEP systems beyond a simple grouping feature. |
https://en.wikipedia.org/wiki/List%20of%20linear%20ordinary%20differential%20equations | This is a list of named linear ordinary differential equations.
A–Z
{| class="wikitable sortable" style="background: white; color: black; text-align: left"
|-style="background: #eee"
!Name
!Order
!Equation
!Applications
|-
|Airy
|2
|
|Optics
|-
|Bessel
|2
|
|Wave propagation
|-
|Cauchy-Euler
|n
|
|
|-
|Chebyshev
|2
|
|Orthogonal polynomials
|-
|Damped harmonic oscillator
|2
|
|Damping
|-
|Frenet-Serret
|1
|
|Differential geometry
|-
|General Laguerre
|2
|
|Hydrogen atom
|-
|General Legendre
|2
|
|
|-
|Harmonic oscillator
|2
|
|Simple harmonic motion
|-
|Heun
|2
|
|
|-
|Hill
|2
|, (f periodic)
|Physics
|-
|Hypergeometric
|2
|
|
|-
|Kummer
|2
|
|
|-
|Laguerre
|2
|
|
|-
|Legendre
|2
|
|Orthogonal polynomials
|-
|Matrix
|1
|
|
|-
|Picard-Fuchs
|2
|
|Elliptic curves
|-
|Riemann
|2
|
|
|-
|Quantum harmonic oscillator
|2
|
|Quantum mechanics
|-
|Sturm-Liouville
|2
|
|Applied mathematics
|}
See also
List of nonlinear ordinary differential equations
List of nonlinear partial differential equations
List of named differential equations
Equations, differential, ordinary, linear |
https://en.wikipedia.org/wiki/SPT20 | Transcription factor SPT20 is a regulator of transcription. It can recruit TATA binding protein (TBP) and possible other base factors to bind to TATA box. The model of its action by example Saccharomyces cerevisiae was studied. It functions as a component of the transcriptional regulatory complex histone-acetylation a (HAT) SAGA, SALSA and FIG. SAGA is involved in the regulation of transcription-dependent RNA polymerase II about 10% of the yeast gene. In promoter, SAGA is required to engage basal transcription mechanisms. Affects RNA polymerase II transcription activity through various activities, such as TBP interaction (SPT3, SPT8 and SPT20) and promoter selectivity, interaction with transcription activators (GCN5, ADA2, ADA3 and TRA1) and modification chromatin by histone acetylation (GCN5) and ubiquitin deacetylation (UBP8). SAGA acetylates nucleosome or histone H3 to some extent (to form H3K9ac, H3K14ac, H3K18ac, and H3K23ac).
SAGA interacts with DNA via upstream activation sequences (UAS). SALSA, an altered form of SAGA, may be involved in positive regulation transcription. It is suggested that SLIK has partially overlapping functions with SAGA. Preferably acetylation methylated histone H3, at least after activation at the GAL1-10 locus. "ADA5 / SPT20 links the ADA and SPT genes, which are involved in the transcription of yeast". |
https://en.wikipedia.org/wiki/Tamilla%20Nasirova | Tamilla Nasirova (; 20 October 1936 – 12 April 2023) was an Azerbaijani mathematician. She specialized in probability theory and is known for her discoveries pertaining to the semi-Markov process. She was a professor at Baku State University from 1980 to 2018 and at the Karadeniz Technical University from 1996 to 2000. Nasirova was the first woman to earn a doctorate in mathematics in Azerbaijan and the first Azerbaijani woman to become a professor of mathematics.
Biography
Tamilla Nasirova was born in Nəvahı, Azerbaijan on 20 October 1936. She attended School No. 176 in Baku and graduated in 1953. She enrolled at Azerbaijan State University (now Baku State University) and graduated in 1958. After studying at the Ukrainian Academy of Sciences and Moscow State University, she earned a Doctor of Philosophy at the Tashkent University of Information Technologies in 1964. In 1980, Nasirova was given a position as an associate professor of mathematics at Baku State University, becoming the first woman to hold such a position in Azerbaijan. She became a full professor in 1995. She also taught at the Karadeniz Technical University in Turkey from 1996 to 2000. Nasirova continued teaching at Baku State University until 2018, teaching probability theory and mathematical statistics.
Nasirova worked in probability theory and is known for her work involving semi-Markov processes, proving the ergodic theorem of semi-Markov processes and advancing several related developments that influenced their study. Nasirova was a researcher for the Azerbaijan National Academy of Sciences Institute of Control Systems for much of her life, beginning in 1958, continuing until 1980, and resuming her work in 1994. During her career, she published a total of 96 scientific works and trained ten doctoral students. She was awarded three Azerbaijani Certificates of Honor: two from Baku State University in 2007 and 2016, and one from the National Academy of Sciences in 2016. She was also recognized a |
https://en.wikipedia.org/wiki/Adenoma | An adenoma is a benign tumor of epithelial tissue with glandular origin, glandular characteristics, or both. Adenomas can grow from many glandular organs, including the adrenal glands, pituitary gland, thyroid, prostate, and others. Some adenomas grow from epithelial tissue in nonglandular areas but express glandular tissue structure (as can happen in familial polyposis coli). Although adenomas are benign, they should be treated as pre-cancerous. Over time adenomas may transform to become malignant, at which point they are called adenocarcinomas. Most adenomas do not transform. However, even though benign, they have the potential to cause serious health complications by compressing other structures (mass effect) and by producing large amounts of hormones in an unregulated, non-feedback-dependent manner (causing paraneoplastic syndromes). Some adenomas are too small to be seen macroscopically but can still cause clinical symptoms.
Histopathology
Adenoma is a benign tumor of glandular tissue, such as the mucosa of stomach, small intestine, and colon, in which tumor cells form glands or gland like structures.
In hollow organs (digestive tract), the adenoma grows into the lumen - adenomatous polyp or polypoid adenoma. Adenomatous polyps may be classified based on morphology in order to identify lesions at increased risk of malignant transformation. For example, adenomatous polyps in the colon may be pedunculated (lobular head with a long slender stalk) or sessile (broad base).
The adenomatous proliferation is characterized by different degrees of cell dysplasia (atypia or loss of normal differentiation of epithelium) irregular cells with hyperchromatic nuclei, stratified or pseudostratified nuclei, nucleolus, decreased mucosecretion, and mitosis. The architecture may be tubular, villous, or tubulo-villous. Basement membrane and muscularis mucosae are intact.
Locations
Colon
Adenomas of the colon, also called adenomatous polyps, are quite prevalent. They are found |
https://en.wikipedia.org/wiki/Sonic%20black%20hole | A sonic black hole, sometimes called a dumb hole or acoustic black hole, is a phenomenon in which phonons (sound perturbations) are unable to escape from a region of a fluid that is flowing more quickly than the local speed of sound. They are called sonic, or acoustic, black holes because these trapped phonons are analogous to light in astrophysical (gravitational) black holes. Physicists are interested in them because they have many properties similar to astrophysical black holes and, in particular, emit a phononic version of Hawking radiation. This Hawking radiation can be spontaneously created by quantum vacuum fluctuations, in close analogy with Hawking radiation from a real black hole. On the other hand, the Hawking radiation can be stimulated in a classical process. The boundary of a sonic black hole, at which the flow speed changes from being greater than the speed of sound to less than the speed of sound, is called the event horizon.
A rotating sonic black hole was used in 2010 to give the first laboratory testing of superradiance, a process whereby energy is extracted from a black hole.
Sonic black holes are possible because phonons in perfect fluids exhibit the same properties of motion as fields, such as gravity, in space and time. For this reason, a system in which a sonic black hole can be created is called a gravity analogue. Nearly any fluid can be used to create an acoustic event horizon, but the viscosity of most fluids creates random motion that makes features like Hawking radiation nearly impossible to detect. The complexity of such a system would make it very difficult to gain any knowledge about such features even if they could be detected. Many nearly perfect fluids have been suggested for use in creating sonic black holes, such as superfluid helium, one–dimensional degenerate Fermi gases, and Bose–Einstein condensate. Gravity analogues other than phonons in a fluid, such as slow light and a system of ions, have also been proposed for studyin |
https://en.wikipedia.org/wiki/Cognitive%20radio | A cognitive radio (CR) is a radio that can be programmed and configured dynamically to use the best wireless channels in its vicinity to avoid user interference and congestion. Such a radio automatically detects available channels in wireless spectrum, then accordingly changes its transmission or reception parameters to allow more concurrent wireless communications in a given spectrum band at one location. This process is a form of dynamic spectrum management.
Description
In response to the operator's commands, the cognitive engine is capable of configuring radio-system parameters. These parameters include "waveform, protocol, operating frequency, and networking". This functions as an autonomous unit in the communications environment, exchanging information about the environment with the networks it accesses and other cognitive radios (CRs). A CR "monitors its own performance continuously", in addition to "reading the radio's outputs"; it then uses this information to "determine the RF environment, channel conditions, link performance, etc.", and adjusts the "radio's settings to deliver the required quality of service subject to an appropriate combination of user requirements, operational limitations, and regulatory constraints".
Some "smart radio" proposals combine wireless mesh network—dynamically changing the path messages take between two given nodes using cooperative diversity; cognitive radio—dynamically changing the frequency band used by messages between two consecutive nodes on the path; and software-defined radio—dynamically changing the protocol used by message between two consecutive nodes.
History
The concept of cognitive radio was first proposed by Joseph Mitola III in a seminar at KTH Royal Institute of Technology in Stockholm in 1998 and published in an article by Mitola and Gerald Q. Maguire, Jr. in 1999. It was a novel approach in wireless communications, which Mitola later described as:
The point in which wireless personal digital assistants ( |
https://en.wikipedia.org/wiki/Exposed.su | Exposed.su was a website run by Russian hackers focused on the listing of personal information of celebrities, and other high-profile figures. Among the high-profile victims include Michelle Obama, Donald Trump, Arnold Schwarzenegger, Kim Kardashian, Joe Biden, Hillary Clinton, Beyonce and Robert Mueller. The "doxed" documents, which are hosted on the website, include Social Security numbers, credit histories, loan documents and mortgage information of the individuals.
The credit history information appears to have been obtained through the hacking of 3 US credit history databases, Equifax, Experian and TransUnion, by the hacker CosmoTheGod.
In April 2013 Brian Krebs linked his swatting incident to the coverage of this site.
In 2017, a teenager named Eric Taylor, also known by his hacker handle CosmoTheGod, was sentenced to 36 months by United States District Court for the District of Columbia on charges of cybercrime with regards to a conspiracy that resulted in the disclosure of personal information of Trump, John Brennan, Obama, among others on the website. Previously in 2016, a New Yorker named Mir Islam was also arrested by the federal agents for posting CIA director John Brennan's confidential information to Exposed.su and "swatting" 50 people including Michelle Obama and Robert Mueller.
The site was shut down in March 2013 before jumping to other domains and has since been mirrored on a Tor hidden service. |
https://en.wikipedia.org/wiki/75th%20meridian%20east | The meridian 75° east of Greenwich is a line of longitude that extends from the North Pole across the Arctic Ocean, Asia, the Indian Ocean, the Southern Ocean, and Antarctica to the South Pole.
The 75th meridian east forms a great circle with the 105th meridian west.
From Pole to Pole
Starting at the North Pole and heading south to the South Pole, the 75th meridian east passes through:
{| class="wikitable plainrowheaders"
! scope="col" width="125" | Co-ordinates
! scope="col" | Country, territory or sea
! scope="col" | Notes
|-
| style="background:#b0e0e6;" |
! scope="row" style="background:#b0e0e6;" | Arctic Ocean
| style="background:#b0e0e6;" |
|-valign="top"
| style="background:#b0e0e6;" |
! scope="row" style="background:#b0e0e6;" | Kara Sea
| style="background:#b0e0e6;" | Passing just east of Shokalsky Island, Yamalo-Nenets Autonomous Okrug,
|-
|
! scope="row" |
| Yamalo-Nenets Autonomous Okrug — Gydan Peninsula
|-
| style="background:#b0e0e6;" |
! scope="row" style="background:#b0e0e6;" | Gulf of Ob
| style="background:#b0e0e6;" |
|-
|
! scope="row" |
| Yamalo-Nenets Autonomous Okrug — Gydan Peninsula
|-
| style="background:#b0e0e6;" |
! scope="row" style="background:#b0e0e6;" | Taz Estuary
| style="background:#b0e0e6;" |
|-valign="top"
|
! scope="row" |
| Yamalo-Nenets Autonomous Okrug Khanty-Mansi Autonomous Okrug — from Tyumen Oblast — from Omsk Oblast — from
|-
|
! scope="row" |
| Passing through Lake Balkhash
|-
|
! scope="row" |
|
|-valign="top"
|
! scope="row" |
| Xinjiang
|-
|
! scope="row" |
|
|-valign="top"
|
! scope="row" |
| Xinjiang
|-valign="top"
|
! scope="row" |
| Gilgit-Baltistan — claimed by Azad Kashmir — from , claimed by
|-
|
! scope="row" |
|Jammu and Kashmir
|-
|
! scope="row" |
| Punjab
|-valign="top"
|
! scope="row" |
| Punjab Haryana— from Rajasthan — from Madhya Pradesh — from Maharashtra — from Karnataka — from Kerala — from Karnataka — from Kerala — from
|-
| style="background:#b0e0e6;" |
https://en.wikipedia.org/wiki/Hausdorff%20Medal | The Hausdorff medal is a mathematical prize awarded every two years by the European Set Theory Society. The award recognises the work considered to have had the most impact within set theory among all articles published in the previous five years. The award is named after the German mathematician Felix Hausdorff (1868–1942).
Winners
2013: Hugh Woodin for his articles "Suitable extender models I" (J. Math. Log. 10 (2010), no. 1–2, pp. 101–339) and "Suitable extender models II: beyond ω-huge" (J. Math. Log. 11 (2011), no. 2, pp. 115–436).
2015: Ronald Jensen and John R. Steel for their article " without the measurable" (The Journal of Symbolic Logic, Volume 78, Issue 3 (2013), pp. 708–734).
2017: Maryanthe Malliaris and Saharon Shelah for their article "General topology meets model theory, on 𝔭 and 𝔱" (Proc. Natl. Acad. Sci. USA 110 (2013), no. 33, 13300–13305).
2019: Itay Neeman for his work on "the new method of iterating forcing using side conditions and the tree property".
2022: David Asperó and Ralf Schindler for their positive solution to the long standing conjecture that MM++, a strong form of Martin’s Maximum, implies Woodin’s Axiom (*).
See also
List of mathematics awards |
https://en.wikipedia.org/wiki/Wyckoff%20positions | In crystallography, a Wyckoff position is any point in a set of points whose site symmetry groups (see below) are all conjugate subgroups one of another. Crystallography tables give the Wyckoff positions for different space groups.
History
The Wyckoff positions are named after Ralph Walter Graystone Wyckoff, an American X-ray crystallographer who authored several books in the field. His 1922 book, The Analytical Expression of the Results of the Theory of Space Groups, contained tables with the positional coordinates, both general and special, permitted by the symmetry elements. This book was the forerunner of International Tables for X-ray Crystallography, which first appeared in 1935.
Definition
For any point in a unit cell, given by fractional coordinates, one can apply a symmetry operation to the point. In some cases it will move to new coordinates, while in other cases the point will remain unaffected. For example, reflecting across a mirror plane will switch all the points left and right of the mirror plane, but points exactly on the mirror plane itself will not move. We can test every symmetry operation in the crystal's point group and keep track of whether the specified point is invariant under the operation or not. The (finite) list of all symmetry operations which leave the given point invariant taken together make up another group, which is known as the site symmetry group of that point. By definition, all points with the same site symmetry group, or a conjugate site symmetry group, are assigned the same Wyckoff position.
The Wyckoff positions are designated by a letter, often preceded by the number of positions that are equivalent to a given position with that letter, in other words the number of positions in the unit cell to which the given position is moved by applying all the elements of the space group. For instance, 2a designates the positions left where they are by a certain subgroup, and indicates that other symmetry elements move the point to |
https://en.wikipedia.org/wiki/Trusted%20timestamping | Trusted timestamping is the process of securely keeping track of the creation and modification time of a document. Security here means that no one—not even the owner of the document—should be able to change it once it has been recorded provided that the timestamper's integrity is never compromised.
The administrative aspect involves setting up a publicly available, trusted timestamp management infrastructure to collect, process and renew timestamps.
History
The idea of timestamping information is centuries old. For example, when Robert Hooke discovered Hooke's law in 1660, he did not want to publish it yet, but wanted to be able to claim priority. So he published the anagram ceiiinosssttuv and later published the translation ut tensio sic vis (Latin for "as is the extension, so is the force"). Similarly, Galileo first published his discovery of the phases of Venus in the anagram form.
Sir Isaac Newton, in responding to questions from Leibniz in a letter in 1677, concealed the details of his "fluxional technique" with an anagram:
The foundations of these operations is evident enough, in fact; but because I cannot proceed with the explanation of it now, I have preferred to conceal it thus: 6accdae13eff7i3l9n4o4qrr4s8t12ux. On this foundation I have also tried to simplify the theories which concern the squaring of curves, and I have arrived at certain general Theorems.
Trusted digital timestamping has first been discussed in literature by Stuart Haber and W. Scott Stornetta.
Classification
There are many timestamping schemes with different security goals:
PKI-based – timestamp token is protected using PKI digital signature.
Linking-based schemes – timestamp is generated in such a way that it is related to other timestamps.
Distributed schemes – timestamp is generated in cooperation of multiple parties.
Transient key scheme – variant of PKI with short-living signing keys.
MAC – simple secret key based scheme, found in ANSI ASC X9.95 Standard.
Database – |
https://en.wikipedia.org/wiki/Centered%20decagonal%20number | A centered decagonal number is a centered figurate number that represents a decagon with a dot in the center and all other dots surrounding the center dot in successive decagonal layers. The centered decagonal number for n is given by the formula
Thus, the first few centered decagonal numbers are
1, 11, 31, 61, 101, 151, 211, 281, 361, 451, 551, 661, 781, 911, 1051, ...
Like any other centered k-gonal number, the nth centered decagonal number can be reckoned by multiplying the (n − 1)th triangular number by k, 10 in this case, then adding 1. As a consequence of performing the calculation in base 10, the centered decagonal numbers can be obtained by simply adding a 1 to the right of each triangular number. Therefore, all centered decagonal numbers are odd and in base 10 always end in 1.
Another consequence of this relation to triangular numbers is the simple recurrence relation for centered decagonal numbers:
where
Relation to other sequences
N is a Centered decagonal number iff 20N + 5 is a Square number.
Generating Function
The generating function of the centered decagonal number is
Continued fraction forms
has the continued fraction expansion [5n-3;{2,2n-2,2,10n-6}].
See also
[ordinary] decagonal number |
https://en.wikipedia.org/wiki/Animal%20embryonic%20development | In developmental biology, animal embryonic development, also known as animal embryogenesis, is the developmental stage of an animal embryo. Embryonic development starts with the fertilization of an egg cell (ovum) by a sperm cell, (spermatozoon). Once fertilized, the ovum becomes a single diploid cell known as a zygote. The zygote undergoes mitotic divisions with no significant growth (a process known as cleavage) and cellular differentiation, leading to development of a multicellular embryo after passing through an organizational checkpoint during mid-embryogenesis. In mammals, the term refers chiefly to the early stages of prenatal development, whereas the terms fetus and fetal development describe later stages.
The main stages of animal embryonic development are as follows:
The zygote undergoes a series of cell divisions (called cleavage) to form a structure called a morula.
The morula develops into a structure called a blastula through a process called blastulation.
The blastula develops into a structure called a gastrula through a process called gastrulation.
The gastrula then undergoes further development, including the formation of organs (organogenesis).
The embryo then transforms into the next stage of development, the nature of which varies between different animal species (examples of possible next stages include a fetus and a larva).
Fertilization and the zygote
The egg cell is generally asymmetric, having an animal pole (future ectoderm).
It is covered with protective envelopes, with different layers. The first envelope – the one in contact with the membrane of the egg – is made of glycoproteins and is known as the vitelline membrane (zona pellucida in mammals). Different taxa show different cellular and acellular envelopes englobing the vitelline membrane.
Fertilization is the fusion of gametes to produce a new organism. In animals, the process involves a sperm fusing with an ovum, which eventually leads to the development of an embryo. Depen |
https://en.wikipedia.org/wiki/Letterlike%20Symbols | Letterlike Symbols is a Unicode block containing 80 characters which are constructed mainly from the glyphs of one or more letters. In addition to this block, Unicode includes full styled mathematical alphabets, although Unicode does not explicitly categorize these characters as being "letterlike."
Symbols
Glyph variants
Variation selectors may be used to specify chancery (U+FE00) vs roundhand (U+FE01) forms, if the font supports them:
The remainder of the set is at Mathematical Alphanumeric Symbols.
Block
Emoji
The Letterlike Symbols block contains two emoji:
U+2122 and U+2139.
The block has four standardized variants defined to specify emoji-style (U+FE0F VS16) or text presentation (U+FE0E VS15) for the
two emoji, both of which default to a text presentation.
History
The following Unicode-related documents record the purpose and process of defining specific characters in the Letterlike Symbols block:
See also
Greek in Unicode
Latin script in Unicode
Unicode symbols
Mathematical operators and symbols in Unicode
Mathematical Alphanumeric Symbols (Unicode block)
Currency Symbols (Unicode block) |
https://en.wikipedia.org/wiki/B%C3%A9zout%20matrix | In mathematics, a Bézout matrix (or Bézoutian or Bezoutiant) is a special square matrix associated with two polynomials, introduced by and and named after Étienne Bézout. Bézoutian may also refer to the determinant of this matrix, which is equal to the resultant of the two polynomials. Bézout matrices are sometimes used to test the stability of a given polynomial.
Definition
Let and be two complex polynomials of degree at most n,
(Note that any coefficient or could be zero.) The Bézout matrix of order n associated with the polynomials f and g is
where the entries result from the identity
It is an n × n complex matrix, and its entries are such that if we let for each , then:
To each Bézout matrix, one can associate the following bilinear form, called the Bézoutian:
Examples
For n = 3, we have for any polynomials f and g of degree (at most) 3:
Let and be the two polynomials. Then:
The last row and column are all zero as f and g have degree strictly less than n (which is 4). The other zero entries are because for each , either or is zero.
Properties
is symmetric (as a matrix);
;
;
is a bilinear function;
is a real matrix if f and g have real coefficients;
is nonsingular with if and only if f and g have no common roots.
with has determinant which is the resultant of f and g.
Applications
An important application of Bézout matrices can be found in control theory. To see this, let f(z) be a complex polynomial of degree n and denote by q and p the real polynomials such that f(iy) = q(y) + ip(y) (where y is real). We also denote r for the rank and σ for the signature of . Then, we have the following statements:
f(z) has n − r roots in common with its conjugate;
the left r roots of f(z) are located in such a way that:
(r + σ)/2 of them lie in the open left half-plane, and
(r − σ)/2 lie in the open right half-plane;
f is Hurwitz stable if and only if is positive definite.
The third statement gives a necessary and sufficient |
https://en.wikipedia.org/wiki/231%20%28number%29 | 231 (two hundred [and] thirty-one) is the natural number following 230 and preceding 232.
Two hundred [and] thirty-one 231 = 3·7·11, sphenic number, triangular number, doubly triangular number, hexagonal number, octahedral number, centered octahedral number, the number of integer partitions of 16, Mertens function returns 0, and is the number of cubic inches in a U.S. liquid gallon. |
https://en.wikipedia.org/wiki/BBC%20Player | BBC Player is an authenticated multi-genre subscription video on demand service operated by BBC Studios, formerly BBC Worldwide, for the Asia market. It is available online and as an app.
The service debuted in Singapore in summer 2016 to StarHub subscribers, in Malaysia in March 2017 with Telekom Malaysia, in Poland in June 2022 with Canal+, and most recently in Taiwan in August 2023 with Taiwan Mobile myVideo.
BBC Player offers curated content from BBC global brands – BBC Earth, BBC First, BBC Lifestyle, CBeebies and BBC World News. Although not available to watch on linear TV in Asia, BBC Brit is available to watch on BBC Player.
The most popular British programmes are available through the service, including Top Gear, Doctor Who, The Great British Bake Off and Sherlock. |
https://en.wikipedia.org/wiki/List%20of%20Facebook%20features | Facebook is a social-network service website launched on February 4, 2004, by Mark Zuckerberg. The following is a list of software and technology features that can be found on the Facebook website and mobile app and are available to users of the social media site.
Facebook structure
News Feed
The news feed is the primary system through which users are exposed to content posted on the network. Using a secret method (initially known as EdgeRank), Facebook selects a handful of updates to actually show users every time they visit their feed, out of an average of 1500 updates they can potentially receive.
On September 6, 2006, Ruchi Sanghvi announced a new home page feature called News Feed. Originally, when users logged into Facebook, they were presented with a customizable version of their own profile. The new layout, by contrast, created an alternative home page in which users saw a constantly updated list of their friends' Facebook activity. News Feed highlights information that includes profile changes, upcoming events, and birthdays, among other updates. This has enabled spammers and other users to manipulate these features by creating illegitimate events or posting fake birthdays to attract attention to their profile or cause. News Feed also shows conversations taking place between the walls of a user's friends. An integral part of the News Feed interface is the Mini Feed, a news stream on the user's profile page that shows updates about that user. Unlike in the News Feed, the user can delete events from the Mini Feed after they appear so that they are no longer visible to profile visitors. In 2011, Facebook updated the News Feed to show top stories and most recent stories in one feed, and the option to highlight stories to make them top stories, as well as to un-highlight stories. In response to users' criticism, Facebook later updated the News Feed to allow users to view recent stories first.
Initially, the addition of the News Feed caused some discontent |
https://en.wikipedia.org/wiki/C.%20Thomas%20Elliott | Charles Thomas Elliott (known as Tom Elliott), (born 16 January 1939), is a scientist in the fields of narrow gap semiconductor and infrared detector research.
Early life
Hailing from County Durham, he attended Washington Grammar Technical School. After gaining his Ph.D. he worked at the University of Manchester
Career
He joined RRE in Malvern, Worcestershire in the late 1960s. In the 1970s he invented the SPRITE detector (Signal PRocessing In The Element) which was also known as the TED (Tom Elliott's Detector). This was a photoconductor device in which the infrared scene was scanned across the detector (made from HgCdTe) at the same rate as the carriers drifted under an applied controlled constant bias current. This device became part of TICM - the standard UK thermal imaging common module used since the 1980s by UK armed forces. Tom Elliott received a Rank Prize in 1982 for this work and was elected a Fellow of the Royal Society in 1988. He was appointed CBE in the 1994 Birthday Honours.
He won the Clifford Paterson Medal and Prize in 1997.
Tom Elliott also contributed to the development of the semiconductor indium antimonide (InSb) as an infrared detector, magnetic sensor and fast, low voltage transistor material. He was involved in the exploitation of negative luminescence in diode structures.
He retired from the successor to RRE, DERA in 1999 and is an honorary professor at Heriot-Watt University.
Personal life
A conference centre at DERA Malvern (by 2007 QinetiQ) was named 'The Tom Elliott Centre' in his honour when opened by the Princess Royal in 2007. He lives in Malvern.
Bibliography
Infrared Detectors and Emitters: Materials and Devices, edited by Peter Capper and C T Elliott, Springer (2000)
An infrared detector with integrated signal processing, C. T. Elliott, Electron Devices Meeting, 1982 International, Vol. 28 Page(s): 132 - 135 (1982)
Uncooled InSb/In1–xAlxSb mid-infrared emitter, T. Ashley, C. T. Elliott, N. T. Gordon, R. S. Hall, A |
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