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https://en.wikipedia.org/wiki/Complex%20conjugate%20line
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In complex geometry, the complex conjugate line of a straight line is the line that it becomes by taking the complex conjugate of each point on this line.
This is the same as taking the complex conjugates of the coefficients of the line. So if the equation of is , then the equation of its conjugate is .
The conjugate of a real line is the line itself.
The intersection point of two conjugated lines is always real.
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https://en.wikipedia.org/wiki/Sunning%20%28behaviour%29
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Sunning or basking, sometimes also known as sunbathing, is a thermoregulatory or comfort behaviour used by humans, animals, especially birds, reptiles, and insects, to help raise their body temperature, reduce the energy needed for temperature maintenance or to provide comfort. They may also have additional functions of ridding animals of ectoparasites, bacteria, or excess moisture.
Birds
Birds adopt special postures when sunning, these may include spreading out their feathers, flattening their body on soil, showing either their upper parts to the Sun or facing the Sun. Some authors separate the behaviours into sun-basking and sun-exposure - the former term used when the behaviour is strictly thermoregulatory in function while the latter term may be more appropriate if the behaviour serves functions other than raising body temperature.
In some species, the sunbathing posture is adopted in very hot weather and the birds sometimes stay in close contact with hot soil. Birds may fluff up their feathers, expose their preen-gland, lean to one side and so on. The wings may be turned inside out as in the boobies or held in delta-wing positions as in herons and storks or held outspread as by vultures. Swallows were observed to indulge in the activity for very short durations and this appeared to induce hyperthermia leading to them gaping to cool. Observers have suggested that the purpose might not be thermoregulation in these cases. A theory that birds obtained vitamin D by allowing precursors in the preen-gland secretions to be converted by ultraviolet radiation is considered to be unsupported. Large soaring birds such as Gyps vultures may use sun-bathing postures to help in stiffening their feathers as they used such postures only prior to flying and not during the early morning hours. Another theory is that ectoparasites may be killed or forced to move away from inaccessible parts of the body to more accessible areas where they can be removed through preening. This is
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https://en.wikipedia.org/wiki/Decision%20EXpert
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DEX (Decision EXpert) is a qualitative multi-criteria decision analysis (MCDA) method for decision making and is implemented in DEX software. This method was developed by a research team led by Bohanec, Bratko, and Rajkovič. The method supports decision makers in making complex decisions based on multiple, possibly conflicting, attributes. In DEX, all attributes are qualitative and can take values represented by words, such as “low” or “excellent”. Attributes are generally organized in a hierarchy. The evaluation of decision alternatives is carried out by utility functions, which are represented in the form of decision rules. All attributes (function arguments and outcomes) are assumed to be discrete. Additionally, they can be preferentially ordered, so that a higher ordinal value represents a better preference.
History
The origins of the DEX method can be traced back to the work of Efstathiou and Rajkovič (1979). Their idea was to use words instead of the numbers in multi-criteria decision models and to use tables to represent utility functions. The method was further developed by Slovenian researchers Vladislav Rajkovič and Marko Bohanec, who extended it to cope with hierarchies of attributes and to facilitate the acquisition and explanation of decision knowledge from experts and decision analysts. This method was called DECMAK. In 1987, after an implementation of a supporting computer program, the method was named DEX (Decision EXpert). In the 1990s, DEX was already used to solve complex decision making problems in industry, health-care, project evaluation, housing, and sports. In 2000, DEX was implemented as DEXi software. Updated versions of DEXi, as well as other DEX-related software tools, are accessible on the DEX Software website.
DEX Method
DEX (Decision EXpert) is a multi-criteria decision modelling method. Its main distinguishing characteristics are:
DEX is hierarchical: multi-criteria models developed by DEX consist of attributes, organized in a h
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https://en.wikipedia.org/wiki/Weyl%20sequence
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In mathematics, a Weyl sequence is a sequence from the equidistribution theorem proven by Hermann Weyl:
The sequence of all multiples of an irrational α,
0, α, 2α, 3α, 4α, ...
is equidistributed modulo 1.
In other words, the sequence of the fractional parts of each term will be uniformly distributed in the interval [0, 1).
In computing
In computing, an integer version of this sequence is often used to generate a discrete uniform distribution rather than a continuous one. Instead of using an irrational number, which cannot be calculated on a digital computer, the ratio of two integers is used in its place. An integer k is chosen, relatively prime to an integer modulus m. In the common case that m is a power of 2, this amounts to requiring that k is odd.
The sequence of all multiples of such an integer k,
0, k, 2k, 3k, 4k, …
is equidistributed modulo m.
That is, the sequence of the remainders of each term when divided by m will be uniformly distributed in the interval [0, m).
The term appears to originate with George Marsaglia’s paper "Xorshift RNGs".
The following C code generates what Marsaglia calls a "Weyl sequence":
d += 362437;
In this case, the odd integer is 362437, and the results are computed modulo because d is a 32-bit quantity. The results are equidistributed modulo 232.
See also
List of things named after Hermann Weyl
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https://en.wikipedia.org/wiki/Imitative%20learning
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Imitative learning is a type of social learning whereby new behaviors are acquired via imitation. Imitation aids in communication, social interaction, and the ability to modulate one's emotions to account for the emotions of others, and is "essential for healthy sensorimotor development and social functioning". The ability to match one's actions to those observed in others occurs in humans and animals; imitative learning plays an important role in humans in cultural development. Imitative learning is different from observational learning in that it requires a duplication of the behaviour exhibited by the model, whereas observational learning can occur when the learner observes an unwanted behaviour and its subsequent consequences and as a result learns to avoid that behaviour.
Imitative learning in animals
On the most basic level, research performed by A.L. Saggerson, David N. George, and R.C. Honey showed that pigeons were able to learn a basic process that would lead to the delivery of a reward by watching a demonstrator pigeon. A demonstrator pigeon was trained to peck a panel in response to one stimulus (e.g. a red light) and hop on the panel in response to a second stimulus (e.g. a green light). After proficiency in this task was established in the demonstrator pigeon, other learner pigeons were placed in a video-monitored observation chamber. After every second observed trial, these learner pigeons were then individually placed in the demonstrator pigeon's box and presented the same test. The learner pigeons displayed competent performance on the task, and thus it was concluded that the learner pigeons had formed a response-outcome association while observing. However, the researchers noted that an alternative interpretation of these results could be that the learner pigeons had instead acquired outcome-response associations that guided their behavior and that further testing was needed to establish if this was a valid alternative.
A similar study was
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https://en.wikipedia.org/wiki/HTTP%20Public%20Key%20Pinning
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HTTP Public Key Pinning (HPKP) is an obsolete Internet security mechanism delivered via an HTTP header which allows HTTPS websites to resist impersonation by attackers using misissued or otherwise fraudulent digital certificates. A server uses it to deliver to the client (e.g. web browser) a set of hashes of public keys that must appear in the certificate chain of future connections to the same domain name.
For example, attackers might compromise a certificate authority, and then mis-issue certificates for a web origin. To combat this risk, the HTTPS web server serves a list of “pinned” public key hashes valid for a given time; on subsequent connections, during that validity time, clients expect the server to use one or more of those public keys in its certificate chain. If it does not, an error message is shown, which cannot be (easily) bypassed by the user.
The technique does not pin certificates, but public key hashes. This means that one can use the key pair to get a certificate from any certificate authority, when one has access to the private key. Also the user can pin public keys of root or intermediate certificates (created by certificate authorities), restricting site to certificates issued by the said certificate authority.
Due to HPKP mechanism complexity and possibility of accidental misuse (potentially causing a lockout condition by system administrators), in 2017 browsers deprecated HPKP and in 2018 removed its support in favor of Certificate Transparency.
Mechanism
The server communicates the HPKP policy to the user agent via an HTTP response header field named Public-Key-Pins (or Public-Key-Pins-Report-Only for reporting-only purposes).
The HPKP policy specifies hashes of the subject public key info of one of the certificates in the website's authentic X.509 public key certificate chain (and at least one backup key) in pin-sha256 directives, and a period of time during which the user agent shall enforce public key pinning in max-age directive,
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https://en.wikipedia.org/wiki/Salpicon
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Salpicon (, meaning "hodgepodge" or "medley"; ) is a dish of one or more ingredients diced or minced and bound with a sauce or liquid. There are different versions found in Spanish and the broader Latin American cuisine. A salpicon is sometimes used as stuffing.
In Mexican cuisine and Central American cuisine, the term refers to a salad mixture containing thinly sliced or chopped flank steak, onion, oregano, chile serrano, avocado, tomatoes, and vinegar. The mixture is commonly served on tostadas, tacos or as a filling of poblano peppers. In Honduras, rabbit meat is used.
In Colombian cuisine, salpicón is a fruit cocktail beverage made with a base of watermelon and/or orange juice, which gives it its bright red color, and soda water.
Notes
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https://en.wikipedia.org/wiki/Armorial%20of%20Ukraine
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The following gallery displays the official coats of arms of the 27 oblasts, autonomous republics and cities with special status of Ukraine:
State
Regional
Historical
Coats of Arms of Kingdom of Galicia–Volhynia of Kievan Rus
Coats of Arms of Voivodeships of Polish-Lithuanian Commonwealth
Cossack Hetmanate
Coats of Arms of Governorates of Russian Empire in Ukraine
Coats of Arms of Crownlands of Austrian Empire in Ukraine
Oblasts
Cherkasy Oblast
Chernihiv Oblast
Chernivtsi Oblast
Dnipropetrovsk Oblast
Donetsk Oblast
Ivano-Frankivsk Oblast
Kharkiv Oblast
Kherson Oblast
Khmelnytskyi Oblast
Kyiv Oblast
Kirovohrad Oblast
Luhansk Oblast
Lviv Oblast
Mykolaiv Oblast
Odesa Oblast
Poltava Oblast
Rivne Oblast
Sumy Oblast
Ternopil Oblast
Vinnytsia Oblast
Volyn Oblast
Zakarpattia Oblast
Zaporizhzhia Oblast
Zhytomyr Oblast
See also
Armorial of Little Russia
Coat of arms of Ukraine
Flags of the regions of Ukraine
National symbols of Ukraine
Ukraine
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https://en.wikipedia.org/wiki/Ebadollah%20S.%20Mahmoodian
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Ebadollah S. Mahmoodian (born 18 May 1943 in Zanjan, Iran) is a retired professor of mathematics at the Mathematical Sciences Department of Sharif University of Technology.
He received his Bachelor of Science in 1965 at University of Tehran and his master's degree in 1968 at Shiraz University. He got a Master's and a PhD degree from the University of Pennsylvania in 1971 and 1975, respectively. His thesis advisor were Albert Nijenhuis and Herbert Wilf. He was a professor of mathematics at the Mathematical Sciences Department of Sharif University of Technology since 1983. He co-edited Combinatorics Advances.
Mahmoodian has contributions in graph theory, in particular graph colouring. He has also worked on combinatorial designs, in particular, defining sets, and the relations between all those areas. Mahmoodian is also known for mentoring and research collaborations with Maryam Mirzakhani during her studies at Sharif University.
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https://en.wikipedia.org/wiki/Clothing%20material
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Many materials have been used to make garments throughout history. Grasses, furs and much more complex and exotic materials have been used. Cultures like the Arctic Circle, make their wardrobes out of prepared and decorated furs and skins.[1] Different cultures have added cloth to leather and skins as a way to replace real leather. A wide range of fibers, including natural, cellulose, and synthetic fibers, can be used to weave or knit cloth.
Humans have shown extreme inventiveness in devising clothing solutions to environmental hazards and the distinction between clothing and other protective equipment is not always clear-cut; examples include space suit, air conditioned clothing, armor, diving suit, swimsuit, bee-keeper's protective clothing, motorcycle leathers, high-visibility clothing, and protective clothing in general.
Clothing
Cloth is especially used to make clothing. It is a fabric created through both the spinning and weaving process through which raw cotton is turned into thread via the spinning process and then that thread is woven into the cloth fabric via the weaving process. There are many different types of cloths with different names and uses. The main differences between the types of cloths are distinguished by its fiber art (woven, knitted, felted, and how those techniques were implemented), what fiber it is made from, and its weight. Based on the cloth’s weight, the properties of the fabric (thin or thick, rigid, etc.) can also be distinguished, allowing the differences among different cloths to be more easily detected. Different types of cloth may be used for different types of clothing. For example, a piece of clothing for cold weathers should be made with durable materials on the outside and soft materials on the inside. Clothing for the summer should be made with breathable materials where the wearer can feel cool and comfortable in it.
Examples of clothing materials
Common natural clothing materials are :
Linen
Cashmere
Cotton
Cellul
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https://en.wikipedia.org/wiki/Peter%20M.%20Gruber
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Peter Manfred Gruber (28 August 1941, Klagenfurt – 7 March 2017, Vienna) was an Austrian mathematician working in geometric number theory as well as in convex and discrete geometry.
Biography
Gruber obtained his PhD at the University of Vienna in 1966, under the supervision of Nikolaus Hofreiter. From 1971, he was Professor at the University of Linz, and from 1976, at the TU Wien. He was a member of the Austrian Academy of Sciences, a foreign member of the Russian Academy of Sciences, and a corresponding member of the Bavarian Academy of Sciences and Humanities.
His past doctoral students include Monika Ludwig.
Selected publications
Decorations and awards
1967: Prize of the Austrian Mathematical Society
1978, 1980 and 1982: Chairman of the Austrian Mathematical Society
1991: Full member of the Austrian Academy of Sciences (Corresponding member since 1988)
1996: Medal of the Union of Czech Mathematicians and Physicists
2001: Austrian Cross of Honour for Science and Art, 1st class
2001: Medal of the mathematical and physical faculty of Charles University in Prague
2003: Foreign member of the Russian Academy of Sciences
2008: Grand Silver Medal for Services to the Republic of Austria
2013: Fellow of the American Mathematical Society, for "contributions to the geometry of numbers and to convex and discrete geometry".
Honorary doctorates from the Universities of Siegen, Turin and Salzburg
Member of the Academies of Sciences in Messina and Modena
Corresponding member of the Bavarian Academy of Sciences
Notes
1941 births
2017 deaths
Scientists from Klagenfurt
Austrian mathematicians
Geometers
Number theorists
University of Vienna alumni
Academic staff of Johannes Kepler University Linz
Academic staff of TU Wien
Foreign Members of the Russian Academy of Sciences
Members of the Austrian Academy of Sciences
Recipients of the Austrian Cross of Honour for Science and Art, 1st class
Recipients of the Grand Decoration for Services to the Republic of Austria
Fel
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https://en.wikipedia.org/wiki/MAP3K15
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Mitogen-activated protein kinase kinase kinase 15 is a protein that in humans is encoded by the MAP3K15 gene.
Function
The protein encoded by this gene is a member of the mitogen-activated protein kinase (MAPK) family. These family members function in a protein kinase signal transduction cascade, where an activated MAPK kinase kinase (MAP3K) phosphorylates and activates a specific MAPK kinase (MAP2K), which then activates a specific MAPK. This MAP3K protein plays an essential role in apoptotic cell death triggered by cellular stresses.
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https://en.wikipedia.org/wiki/FKBP7
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FK506 binding protein 7 is a protein that in humans is encoded by the FKBP7 gene. The gene is also known as FKBP23 and PPIase. FKBP7 belongs to the FKBP-type peptidyl-prolyl cis/trans isomerase (PPIase) family. Members of this family exhibit PPIase activity and function as molecular chaperones. The orthologous protein in mouse is located in the endoplasmic reticulum and binds calcium.
Model organisms
Model organisms have been used in the study of FKBP7 function. A conditional knockout mouse line, called Fkbp7tm2a(KOMP)Wtsi was generated as part of the International Knockout Mouse Consortium program — a high-throughput mutagenesis project to generate and distribute animal models of disease to interested scientists — at the Wellcome Trust Sanger Institute.
Male and female animals underwent a standardized phenotypic screen to determine the effects of deletion.
Twenty three tests were carried out on mutant mice, but no significant abnormalities were observed.
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https://en.wikipedia.org/wiki/Johnny%20Lightning
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Johnny Lightning is a brand of diecast model cars launched in 1969 by Topper Corporation (owner of the "Topper Toys" brand), similar to the hugely successful Mattel's Hot Wheels cars. Their claim to fame at that time was that they were extremely fast compared to other brands of die-cast cars. Their most important technology was to mold in a small hook under the front axle so that they could be propelled by a lever-driven catapult, far faster than could be obtained by either gravity, or battery powered "supercharger" devices.
Al Unser Senior won the Indianapolis 500 in 1970 and 1971 in the "Johnny Lightning Special". Topper closed in 1973 and production of Johnny Lightning cars ceased for 23 years. The company made a total of 47 different models.
In 1994 Thomas Lowe of Cassopolis, Michigan became aware of the abandoned trademark and secured the rights to the Johnny Lightning name for his Playing Mantis toy company. He made replicas of his favorite 10 original Johnny Lightning cars. His first customers were Walmart and Toys R Us.
Playing Mantis produced the toy cars under the Johnny Lightning brand name from 1994 to June 2004. Over 600 different models, including replicas of all of the original 1969-71 cars, were produced over that time period.
In 2004 Mr. Lowe sold Playing Mantis (including the Johnny Lightning brand) to RC2 Corporation, which in turn was bought by the Japanese toy company Tomy in 2011. Tomy discontinued the Johnny Lightning line of diecast cars in 2013. The brand continued to maintain a following by a loyal group of collectors. In early 2016 Round 2 LLC, a toy company owned by Thomas Lowe (who also owned Playing Mantis), revived and reintroduced Johnny Lightning vehicles to the toy market for a second time.
Topper
In 1969, Topper Corporation (owner of "Topper Toys" and other brands) introduced Johnny Lightning model cars and track sets in response to the growing 1:64 scale diecast market. New Jersey inventor and author Henry Orenstein owned To
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https://en.wikipedia.org/wiki/Cavendish%20experiment
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The Cavendish experiment, performed in 1797–1798 by English scientist Henry Cavendish, was the first experiment to measure the force of gravity between masses in the laboratory and the first to yield accurate values for the gravitational constant. Because of the unit conventions then in use, the gravitational constant does not appear explicitly in Cavendish's work. Instead, the result was originally expressed as the specific gravity of Earth, or equivalently the mass of Earth. His experiment gave the first accurate values for these geophysical constants.
The experiment was devised sometime before 1783 by geologist John Michell, who constructed a torsion balance apparatus for it. However, Michell died in 1793 without completing the work. After his death the apparatus passed to Francis John Hyde Wollaston and then to Cavendish, who rebuilt the apparatus but kept close to Michell's original plan. Cavendish then carried out a series of measurements with the equipment and reported his results in the Philosophical Transactions of the Royal Society in 1798.
The experiment
The apparatus consisted of a torsion balance made of a wooden rod horizontally suspended from a wire, with two , lead spheres, one attached to each end. Two massive , lead balls, suspended separately, could be positioned away from or to either side of the smaller balls, away. The experiment measured the faint gravitational attraction between the small and large balls, which deflected the torsion balance rod by about 0.16" (or only 0.03" with a stiffer suspending wire).
The two large balls could be positioned either away from or to either side of the torsion balance rod. Their mutual attraction to the small balls caused the arm to rotate, twisting the suspension wire. The arm rotated until it reached an angle where the twisting force of the wire balanced the combined gravitational force of attraction between the large and small lead spheres. By measuring the angle of the rod and knowing the twisting
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https://en.wikipedia.org/wiki/Global%20Design%20Effort
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The Global Design Effort (GDE) was an international team tasked with designing the International Linear Collider (ILC), a particle accelerator to succeed machines such as the Large Hadron Collider (LHC) and the Stanford Linear Accelerator (SLAC), with the endorsement of the International Committee for Future Accelerators. Between 2005–2013, the GDE led planning, research and development, and produced an ILC Technical Design Report.
The Global Design Effort was headed by Barry Barish of Caltech, former director of the LIGO laboratory.
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https://en.wikipedia.org/wiki/Liouville%20function
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The Liouville lambda function, denoted by λ(n) and named after Joseph Liouville, is an important arithmetic function.
Its value is +1 if n is the product of an even number of prime numbers, and −1 if it is the product of an odd number of primes.
Explicitly, the fundamental theorem of arithmetic states that any positive integer n can be represented uniquely as a product of powers of primes: where p1 < p2 < ... < pk are primes and the aj are positive integers. (1 is given by the empty product.) The prime omega functions count the number of primes, with (Ω) or without (ω) multiplicity:
ω(n) = k,
Ω(n) = a1 + a2 + ... + ak.
λ(n) is defined by the formula
.
λ is completely multiplicative since Ω(n) is completely additive, i.e.: Ω(ab) = Ω(a) + Ω(b). Since 1 has no prime factors, Ω(1) = 0 so λ(1) = 1.
It is related to the Möbius function μ(n). Write n as n = a2b where b is squarefree, i.e., ω(b) = Ω(b). Then
The sum of the Liouville function over the divisors of n is the characteristic function of the squares:
Möbius inversion of this formula yields
The Dirichlet inverse of Liouville function is the absolute value of the Möbius function, the characteristic function of the squarefree integers. We also have that .
Series
The Dirichlet series for the Liouville function is related to the Riemann zeta function by
Also:
The Lambert series for the Liouville function is
where is the Jacobi theta function.
Conjectures on weighted summatory functions
The Pólya problem is a question raised made by George Pólya in 1919. Defining
,
the problem asks whether for n > 1. The answer turns out to be no. The smallest counter-example is n = 906150257, found by Minoru Tanaka in 1980. It has since been shown that L(n) > 0.0618672 for infinitely many positive integers n, while it can also be shown via the same methods that L(n) < -1.3892783 for infinitely many positive integers n.
For any , assuming the Riemann hypothesis, we have that the summatory f
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https://en.wikipedia.org/wiki/The%20Secret%20%282006%20film%29
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The Secret is a 2006 Australian-American spirituality documentary consisting of a series of interviews designed to demonstrate the New Thought "law of attraction", the belief that everything one wants or needs can be satisfied by believing in an outcome, repeatedly thinking about it, and maintaining positive emotional states to "attract" the desired outcome.
The film and the subsequent publication of the book of the same name attracted interest from media figures such as Oprah Winfrey, Ellen DeGeneres and Larry King.
Synopsis
The Secret, described as a self-help film, uses a documentary format to present a concept titled "law of attraction". As described in the film, the "Law of Attraction" hypothesis posits that feelings and thoughts can attract events, feelings, and experiences, from the workings of the cosmos to interactions among individuals in their physical, emotional, and professional affairs. The film also suggests that there has been a strong tendency by those in positions of power to keep this central principle hidden from the public.
Foundations in New Thought ideas
The authors of The Secret cite the New Thought movement which began in the late 18th century as the historical basis for their ideas.
The New Thought book The Science of Getting Rich by Wallace Wattles, the source Rhonda Byrne cites as inspiration for the film, was preceded by numerous other New Thought books, including the 1906 book Thought Vibration or the law of attraction in the Thought World by William Walker Atkinson, editor of New Thought magazine. Other New Thought books Byrne is purported to have read include self-help authors like Prentice Mulford's 19th-century Thoughts Are Things; and Robert Collier's Secret of the Ages from 1926.
Carolyn Sackariason of the Aspen Times, when commenting about Byrne's intention to share The Secret with the world, identifies the Rosicrucians as keepers of The Secret.
Production
The film was created by Prime Time Productions of Melbourne, Austr
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https://en.wikipedia.org/wiki/Ice%20algae
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Ice algae are any of the various types of algal communities found in annual and multi-year sea, and terrestrial lake ice or glacier ice.
On sea ice in the polar oceans, ice algae communities play an important role in primary production. The timing of blooms of the algae is especially important for supporting higher trophic levels at times of the year when light is low and ice cover still exists. Sea ice algal communities are mostly concentrated in the bottom layer of the ice, but can also occur in brine channels within the ice, in melt ponds, and on the surface.
Because terrestrial ice algae occur in freshwater systems, the species composition differs greatly from that of sea ice algae. In particular, terrestrial glacier ice algae communities are significant in that they change the color of glaciers and ice sheets, impacting the reflectivity of the ice itself.
Sea ice algae
Adapting to the sea ice environment
Microbial life in sea ice is extremely diverse, and includes abundant algae, bacteria and protozoa. Algae in particular dominate the sympagic environment, with estimates of more than 1000 unicellular eukaryotes found to associate with sea ice in the Arctic. Species composition and diversity vary based on location, ice type, and irradiance. In general, pennate diatoms such as Nitschia frigida (in the Arctic) and Fragilariopsis cylindrus (in the Antarctic) are abundant. Melosira arctica, which forms up to meter-long filaments attached to the bottom of the ice, are also widespread in the Arctic and are an important food source for marine species.
While sea ice algae communities are found throughout the column of sea ice, abundance and community composition depends on the time of year. There are many microhabitats available to algae on and within sea ice, and different algal groups have different preferences. For example, in late winter/early spring, motile diatoms like N. frigida have been found to dominate the uppermost layers of the ice, as far as briny
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https://en.wikipedia.org/wiki/Data%20defined%20storage
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Data defined storage (also referred to as a data centric approach) is a marketing term for managing, protecting, and realizing value from data by combining application, information and storage tiers.
This is achieved through a process where users, applications, and devices gain access to a repository of captured metadata that allows them to access, query and manipulate the relevant data to transform it into information, while providing a flexible and scalable platform for storage of the underlying data. The technology abstracts the data entirely from the storage, allowing fully transparent access to users.
Core technology
Data defined storage focuses on metadata with an emphasis on the content, meaning and value of information over the media, type and location of data. Data centric management enables organizations to take a single, unified approach to managing data across large, distributed locations which includes the use of content and metadata indexing. The technology pillars include:
Media Independent Data Storage: Data defined storage removes media centric data storage boundaries within and across solid-state drive, hard disk drive, cloud storage and tape storage platforms, enables linear scale out functionality through a grid based Map Reduce architecture that leverages enterprise object storage technology and provides transparent data access across globally distributed repositories for high volume storage performance.
Data Security & Identity Management: Data defined storage allows organizations to gain end-to-end identity management down to the individual user and device level to address growing enterprise mobility requirements and enhanced data security and information governance.
Distributed metadata repository: Data defined storage enables organizations to virtualize aggregate file systems into a single global namespace. At ingestion; file, full text index and custom metadata is collected and stored in a distributed metadata repository. This repositor
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https://en.wikipedia.org/wiki/Divide-and-conquer%20algorithm
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In computer science, divide and conquer is an algorithm design paradigm. A divide-and-conquer algorithm recursively breaks down a problem into two or more sub-problems of the same or related type, until these become simple enough to be solved directly. The solutions to the sub-problems are then combined to give a solution to the original problem.
The divide-and-conquer technique is the basis of efficient algorithms for many problems, such as sorting (e.g., quicksort, merge sort), multiplying large numbers (e.g., the Karatsuba algorithm), finding the closest pair of points, syntactic analysis (e.g., top-down parsers), and computing the discrete Fourier transform (FFT).
Designing efficient divide-and-conquer algorithms can be difficult. As in mathematical induction, it is often necessary to generalize the problem to make it amenable to a recursive solution. The correctness of a divide-and-conquer algorithm is usually proved by mathematical induction, and its computational cost is often determined by solving recurrence relations.
Divide and conquer
The divide-and-conquer paradigm is often used to find an optimal solution of a problem. Its basic idea is to decompose a given problem into two or more similar, but simpler, subproblems, to solve them in turn, and to compose their solutions to solve the given problem. Problems of sufficient simplicity are solved directly.
For example, to sort a given list of n natural numbers, split it into two lists of about n/2 numbers each, sort each of them in turn, and interleave both results appropriately to obtain the sorted version of the given list (see the picture). This approach is known as the merge sort algorithm.
The name "divide and conquer" is sometimes applied to algorithms that reduce each problem to only one sub-problem, such as the binary search algorithm for finding a record in a sorted list (or its analogue in numerical computing, the bisection algorithm for root finding). These algorithms can be implemented mo
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https://en.wikipedia.org/wiki/Shit%20flow%20diagram
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A shit flow diagram (also called excreta flow diagram or SFD) is a high level technical drawing used to display how excreta moves through a location, and functions as a tool to identify where improvements are needed. The diagram has a particular focus on treatment of the waste, and its final disposal or use. SFDs are most often used in developing countries.
Development
In 2012–2013, the World Bank's Water and Sanitation Program sponsored a study on the fecal sludge management of twelve cities with the goal of developing tools for better understanding the flow of excreta through the cities. As a result, Isabel Blackett, Peter Hawkins, and Christiaan Heymans authored The missing link in sanitation service delivery: a review of fecal sludge management in 12 cities. Using this as a basis, a group of excreta management institutions began collaborating in June 2014 to continue development of SFDs.
In November 2014, the SFD Promotion Initiative was started with funding from the Bill & Melinda Gates Foundation. Initially funded as a one year project, it was extended in 2015. In September 2019, the focus of the program shifted to scaling up the current methods of producing SFDs to allow for citywide sanitation in South Asia and Africa. As of 2021 more than 140 shit flow diagram reports have been published. The initiative is managed as part of the Sustainable Sanitation Alliance and is supported by the Bill and Melinda Gates Foundation. It is partnered with many nonprofit organizations such as the Centre for Science and Environment, EAWAG, and the Global Water Security & Sanitation Partnership.
Use in developing countries
The great majority of those living in urban areas, especially the poor, use non-sewer sanitation systems. This poses environmental and health challenges for growing urban areas in developing countries, and many of these countries will need to change their sanitation strategies as their population grows. Using a shit flow diagram allows political leaders
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https://en.wikipedia.org/wiki/Polarizer
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A polarizer or polariser (see spelling differences) is an optical filter that lets light waves of a specific polarization pass through while blocking light waves of other polarizations. It can filter a beam of light of undefined or mixed polarization into a beam of well-defined polarization, that is polarized light. The common types of polarizers are linear polarizers and circular polarizers. Polarizers are used in many optical techniques and instruments, and polarizing filters find applications in photography and LCD technology. Polarizers can also be made for other types of electromagnetic waves besides visible light, such as radio waves, microwaves, and X-rays.
Linear polarizers
Linear polarizers can be divided into two general categories: absorptive polarizers, where the unwanted polarization states are absorbed by the device, and beam-splitting polarizers, where the unpolarized beam is split into two beams with opposite polarization states. Polarizers which maintain the same axes of polarization with varying angles of incidence are often called Cartesian polarizers, since the polarization vectors can be described with simple Cartesian coordinates (for example, horizontal vs. vertical) independent from the orientation of the polarizer surface. When the two polarization states are relative to the direction of a surface (usually found with Fresnel reflection), they are usually termed s and p. This distinction between Cartesian and s–p polarization can be negligible in many cases, but it becomes significant for achieving high contrast and with wide angular spreads of the incident light.
Absorptive polarizers
Certain crystals, due to the effects described by crystal optics, show dichroism, preferential absorption of light which is polarized in particular directions. They can therefore be used as linear polarizers. The best known crystal of this type is tourmaline. However, this crystal is seldom used as a polarizer, since the dichroic effect is strongly wavelen
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https://en.wikipedia.org/wiki/Hugo%20Hadwiger
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Hugo Hadwiger (23 December 1908 in Karlsruhe, Germany – 29 October 1981 in Bern, Switzerland) was a Swiss mathematician, known for his work in geometry, combinatorics, and cryptography.
Biography
Although born in Karlsruhe, Germany, Hadwiger grew up in Bern, Switzerland. He did his undergraduate studies at the University of Bern, where he majored in mathematics but also studied physics and actuarial science. He continued at Bern for his graduate studies, and received his Ph.D. in 1936 under the supervision of Willy Scherrer. He was for more than forty years a professor of mathematics at Bern.
Mathematical concepts named after Hadwiger
Hadwiger's theorem in integral geometry classifies the isometry-invariant valuations on compact convex sets in d-dimensional Euclidean space. According to this theorem, any such valuation can be expressed as a linear combination of the intrinsic volumes; for instance, in two dimensions, the intrinsic volumes are the area, the perimeter, and the Euler characteristic.
The Hadwiger–Finsler inequality, proven by Hadwiger with Paul Finsler, is an inequality relating the side lengths and area of any triangle in the Euclidean plane. It generalizes Weitzenböck's inequality and was generalized in turn by Pedoe's inequality. In the same 1937 paper in which Hadwiger and Finsler published this inequality, they also published the Finsler–Hadwiger theorem on a square derived from two other squares that share a vertex.
Hadwiger's name is also associated with several important unsolved problems in mathematics:
The Hadwiger conjecture in graph theory, posed by Hadwiger in 1943 and called by “one of the deepest unsolved problems in graph theory,” describes a conjectured connection between graph coloring and graph minors. The Hadwiger number of a graph is the number of vertices in the largest clique that can be formed as a minor in the graph; the Hadwiger conjecture states that this is always at least as large as the chromatic number.
The Hadwiger c
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https://en.wikipedia.org/wiki/Steerable%20filter
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In applied mathematics, a steerable filter
is an orientation-selective convolution kernel used for image enhancement and feature extraction that can be expressed via a linear combination of a small set of rotated versions of itself. As an example, the oriented first derivative of a 2D Gaussian is a steerable filter. The oriented first order derivative can be obtained by taking the dot product of a unit vector oriented in a specific direction with the gradient. The basis filters are the partial derivatives of a 2D Gaussian with respect to and .
The process by which the oriented filter is synthesized at any given angle is known as steering, which is used in similar sense as in beam steering for antenna arrays. Applications of steerable filters include edge detection, oriented texture analysis and shape from shading.
Steerable filters may be designed as approximations of a given filter shape up to a desired error or computational complexity.
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https://en.wikipedia.org/wiki/Erytholus
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Erytholus is a form genus for problematic fossils of Cambrian age in South Australia. It has been of special interest because of its morphological similarity with the Ediacaran fossil Ventogyrus, and may have been a late surviving vendobiont. It could be a slime mold.
Description
Erytholus is a globose, chambered fossil, with associated vertical tubular structures. Its preservation in sandstone is similar to the Ediacaran type preservation of the vendobiont Ventogyrus. It is found at depths of within paleosols. Its affinities are uncertain, although it bears a general resemblance to truffles.
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https://en.wikipedia.org/wiki/DMOZ
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DMOZ (from directory.mozilla.org, an earlier domain name, stylized in lowercase in its logo) was a multilingual open-content directory of World Wide Web links. The site and community who maintained it were also known as the Open Directory Project (ODP). It was owned by AOL (now a part of Verizon Media) but constructed and maintained by a community of volunteer editors.
DMOZ used a hierarchical ontology scheme for organizing site listings. Listings on a similar topic were grouped into categories which then included smaller categories.
DMOZ closed on March 17, 2017, because AOL no longer wished to support the project. The website became a single landing page on that day, with links to a static archive of DMOZ, and to the DMOZ discussion forum, where plans to rebrand and relaunch the directory were being discussed.
, a non-editable mirror remained available at dmoztools.net, and it was announced that while the DMOZ URL would not return, a successor version of the directory named Curlie would be provided.
History
DMOZ was founded in the United States as Gnuhoo by Rich Skrenta and Bob Truel in 1998 while they were both working as engineers for Sun Microsystems. Chris Tolles, who worked at Sun Microsystems as the head of marketing for network security products, also signed on in 1998 as a co-founder of Gnuhoo along with co-founders Bryn Dole and Jeremy Wenokur. Skrenta had developed TASS, an ancestor of tin, the popular threaded Usenet newsreader for Unix systems. The original category structure of the Gnuhoo directory was based loosely on the structure of Usenet newsgroups then in existence.
The Gnuhoo directory went live on June 5, 1998. After Richard Stallman and the Free Software Foundation objected to the use of Gnu in the name, Gnuhoo was changed to NewHoo. Yahoo! then objected to the use of Hoo in the name, prompting a proposed name change to ZURL. Prior to switching to ZURL, NewHoo was acquired by Netscape Communications Corporation in October 1998 and becam
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https://en.wikipedia.org/wiki/Twipsy
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Twipsy was the official Mascot of the EXPO 2000 World's Fair held in Hannover. The character was created by the Spanish designer Javier Mariscal. His draft was selected in 1995 by an international jury out of 17 proposals in total. During the course of the Expo, Twipsy could be acquired on the EXPO area on forms of merchandise, ranging from a stuffed plush toy, to apparel such as on T-shirts, mugs, watches and other souvenirs, in addition to those with the EXPO logo. Apart from that, stamps showing Twipsy were released, and full-sized versions of Twipsy were running around on the EXPO area and advertising for the EXPO in other countries.
Appearance
Twipsy has a drop-shaped, colourfully striped body and a demilune yellow head with a large turquoise-colored nose. The area around the eyes, the extension at the back of the head and the chin are black. He's wearing a pointed, high-heeled shoe as well as a rounded flat one. He also has a "normal" thin and an oversized orange arm (which resembles a wing). The colour scheme may vary depending on the version.
Selection
During a design contest in 1995 to elect the ideal official mascot for the Expo 2000 in Hannover, Twipsy was chosen out of 17 proposals in total by an international jury, despite receiving only 1% of the public vote.
According to Mariscal, Twipsy is a burst of energy who came "...from a distant past such as is the Big Bang, a spark in expansion that became a star, a cell, an invertebrate, a reptile, a bird, a mammal..." and into his present form.
Additionally, Mariscal stated that it was his intention to "...embody the triangular aspects of the key theme "Humankind - Nature - Technology" in one figure... therefore [Twipsy] resembles a new type of being, a new human-animal-technological species." Additionally, Twipsy "...harmonise[d] with the corporate design of [the EXPO],", and was also "...adaptable in terms of shape and colour, and [therefore] a suitable playful and informative partner for the EXPO log
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https://en.wikipedia.org/wiki/Landau%27s%20problems
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At the 1912 International Congress of Mathematicians, Edmund Landau listed four basic problems about prime numbers. These problems were characterised in his speech as "unattackable at the present state of mathematics" and are now known as Landau's problems. They are as follows:
Goldbach's conjecture: Can every even integer greater than 2 be written as the sum of two primes?
Twin prime conjecture: Are there infinitely many primes p such that p + 2 is prime?
Legendre's conjecture: Does there always exist at least one prime between consecutive perfect squares?
Are there infinitely many primes p such that p − 1 is a perfect square? In other words: Are there infinitely many primes of the form n2 + 1?
, all four problems are unresolved.
Progress toward solutions
Goldbach's conjecture
Goldbach's weak conjecture, every odd number greater than 5 can be expressed as the sum of three primes, is a consequence of Goldbach's conjecture. Ivan Vinogradov proved it for large enough n (Vinogradov's theorem) in 1937, and Harald Helfgott extended this to a full proof of Goldbach's weak conjecture in 2013.
Chen's theorem, another weakening of Goldbach's conjecture, proves that for all sufficiently large n, where p is prime and q is either prime or semiprime. Bordignon, Johnston, and Starichkova, correcting and improving on Yamada, proved an explicit version of Chen's theorem: every even number greater than is the sum of a prime and a product of at most two primes. Bordignon & Starichkova reduce this to assuming the Generalized Riemann hypothesis for Dirichlet L-functions. Johnson and Starichkova give a version working for all n >= 4 at the cost of using a number which is the product of at most 369 primes rather than a prime or semiprime; under GRH they improve 369 to 33.
Montgomery and Vaughan showed that the exceptional set of even numbers not expressible as the sum of two primes was of density zero, although the set is not proven to be finite. The best current bounds on th
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https://en.wikipedia.org/wiki/Robert%20Ingpen
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Robert Roger Ingpen AM, FRSA (born 13 October 1936) is an Australian graphic designer, illustrator, and writer. For his "lasting contribution" as a children's illustrator he received the biennial, international Hans Christian Andersen Medal in 1986.
Early life
Ingpen was born in Geelong, Victoria, and attended Geelong College to 1957. He graduated with a Diploma of Graphic Art from RMIT in 1958, where he studied with Harold Freedman.
Career
In 1958, Ingpen was appointed by the Commonwealth Scientific and Industrial Research Organisation (CSIRO) as an artist to interpret and communicate the results of scientific research. From 1968 Ingpen worked as a freelance designer, illustrator and author. He was also a member of a United Nations team in Mexico and Peru until 1975, where he designed pamphlets on fisheries and was involved in "a number of Australian conservation and environmental projects". He left the CSIRO to work full-time as a freelance writer in 1968. Ingpen's interest in conservation issues continued, and he was one of the founding members of the Australian Conservation Foundation.
Work
Ingpen has written or illustrated more than 100 published books. These include children's picture books and fictional stories for all ages. His nonfiction books mostly relate to history, conservation, environment and health issues. His most frequent collaborator has been the author and editor Michael Page.
Ingpen has designed many postage stamps for Australia, as well as the flag and coat of arms for the Northern Territory. Ingpen has created a number of public murals in Geelong, Melbourne, Canberra and the Gold Coast in Queensland. He also has designed bronze statues, which include the Poppykettle Fountain in the Geelong Steam Packet Gardens (currently dry due to drought restrictions) and the bronze doors to the Melbourne Cricket Club. His most recent work is the design and working drawings for a tapestry, which was woven by The Victorian Tapestry Workshop, to celebra
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https://en.wikipedia.org/wiki/Crypt%20%28Unix%29
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In Unix computing, crypt or enigma is a utility program used for encryption. Due to the ease of breaking it, it is considered to be obsolete.
The program is usually used as a filter, and it has traditionally been implemented using a "rotor machine" algorithm based on the Enigma machine. It is considered to be cryptographically far too weak to provide any security against brute-force attacks by modern, commodity personal computers.
Some versions of Unix shipped with an even weaker version of the crypt(1) command in order to comply with contemporaneous laws and regulations that limited the exportation of cryptographic software. Some of these were simply implementations of the Caesar cipher (effectively no more secure than ROT13, which is implemented as a Caesar cipher with a well-known key).
History
Cryptographer Robert Morris wrote a M-209-based , which first appeared in Version 3 Unix, to encourage codebreaking experiments; Morris managed to break by hand. Dennis Ritchie automated decryption with a method by James Reeds, and a new Enigma-based version appeared in Version 7, which Reeds and Peter J. Weinberger also broke.
crypt(1) under Linux
Linux distributions generally do not include a Unix compatible version of the crypt command. This is largely due to a combination of three major factors:
crypt is relatively obscure and rarely used for e-mail attachments nor as a file format
crypt is considered to be cryptographically far too weak to withstand brute-force attacks by modern computing systems (Linux systems generally ship with GNU Privacy Guard which is considered to be reasonably secure by modern standards)
During the early years of Linux development and adoption there was some concern that even as weak as the algorithm used by crypt was, that it might still run afoul of ITAR's export controls; so mainstream distribution developers in the United States generally excluded it, leaving their customers to fetch GnuPG or other strong cryptographic software fr
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https://en.wikipedia.org/wiki/European%20Federation%20of%20Clinical%20Chemistry%20and%20Laboratory%20Medicine
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The European Federation of Clinical Chemistry and Laboratory Medicine (EFLM) (formerly EFCC) is a federation of national member societies of clinical chemistry and laboratory medicine from Europe. EFLM has its registered office in Brussels and administrative office in Milan. EFLM is the European Region member of the International Federation of Clinical Chemistry and Laboratory Medicine (IFCC)
History
EFLM was created from the merger of two precursor organisations, The Federation of European Societies of Clinical Chemistry (FESCC), (a European representative of the International Federation of Clinical Chemistry and Laboratory Medicine, IFCC) and the European Community Confederation of Clinical Chemistry (EC4) at the EuroMedlab meeting in Amsterdam in 2007.
Both precursor organizations arose in the 1970s. The increasing overlap between the European Union, represented by EC4 and FESCC, representing geographical Europe, meant that merger was appropriate.
Operations
EFLM has an Executive Board and a range of committees for: science, education and training, quality and regulations, communication and professional representation. Each committee has working groups with a Chair and three full members, there is also a Young Scientist member and they may also have corresponding members, but only one member form each country is permitted.
The Science Committee develops collaborative science in Laboratory Medicine between member organisations or individuals and guidelines to set standards of practice to assist member societies in providing quality patient care. The output of the scientific working groups is scientific papers and presentations which contribute to the science of laboratory medicine internationally; a list of publications can be found on the EFLM web-site (link below). Typically publications are peer-reviewed and published in the journal Clinical Chemistry and Laboratory Medicine. The Working Groups are overseen by the Chair of the Science Committee and their ac
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https://en.wikipedia.org/wiki/Simmondsin
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Simmondsin is a component of jojoba seeds (pronounced "ho-HO-bah") (Simmondsia chinensis). While it had been considered toxic due to jojoba seed meal causing weight loss in animals, in recent years its appetite suppressant effect has also been researched as a potential treatment for obesity. It is thought to reduce appetite by increasing levels of cholecystokinin.
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https://en.wikipedia.org/wiki/NetBIOS
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NetBIOS () is an acronym for Network Basic Input/Output System. It provides services related to the session layer of the OSI model allowing applications on separate computers to communicate over a local area network. As strictly an API, NetBIOS is not a networking protocol. Operating systems of the 1980s (DOS and Novell Netware primarily) ran NetBIOS over IEEE 802.2 and IPX/SPX using the NetBIOS Frames (NBF) and NetBIOS over IPX/SPX (NBX) protocols, respectively. In modern networks, NetBIOS normally runs over TCP/IP via the NetBIOS over TCP/IP (NBT) protocol. NetBIOS is also used for identifying system names in TCP/IP (Windows). Simply stated, it is a protocol that allows communication of data for files and printers through the Session Layer of the OSI Model in a LAN.
History and terminology
NetBIOS is an operating system-level API that allows applications on computers to communicate with one another over a local area network (LAN). The API was created in 1983 by Sytek Inc. for software communication over IBM PC Network LAN technology. On IBM PC Network, as an API alone, NetBIOS relied on proprietary Sytek networking protocols for communication over the wire.
In 1985, IBM went forward with the Token Ring network scheme and produced an emulator of Sytek's NetBIOS API to allow NetBIOS-aware applications from the PC-Network era to work over IBM's new Token Ring hardware. This IBM emulator, named NetBIOS Extended User Interface (NetBEUI), expanded the base NetBIOS API created by Sytek with, among other things, the ability to deal with the greater node capacity of Token Ring. A new networking protocol, NBF, was simultaneously produced by IBM to allow its NetBEUI API (their enhanced NetBIOS API) to provide its services over Token Ring – specifically, at the IEEE 802.2 Logical Link Control layer.
In 1985, Microsoft created its own implementation of the NetBIOS API for its MS-Net networking technology. As in the case of IBM's Token Ring, the services of Microsoft's NetB
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https://en.wikipedia.org/wiki/Chemturion
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The Chemturion is a multi-use, positive pressure totally encapsulating protective suit, manufactured by ILC Dover. It is currently used by Public Health Canada, Boston University, USAMRIID and AI Signal Research, the Center for Disease Control in Atlanta, and many industrial companies such as DuPont, Dow, and Georgia Pacific.
The Chemturion is based on technology developed by ILC Dover as part of the development of the Demilitarization Protective Ensemble, a one-piece disposable suit used in chemical weapons disposal.
The Chemturion is commonly used in biohazard environments, including BSL4 environments, and is sometimes known as the "blue suit" because of its colour. Other suits used in BSL4 environments include Honeywell Safety's Delta suits, and HVO suits manufactured by HVO-ISSI-Deutschland GmbH.
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https://en.wikipedia.org/wiki/Locanto
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locanto is a worldwide Locanto only network with areas dedicated to jobs, personals, for rent, for sale, services, community, real estate, vehicles, and pets.
Background
The Locanto Classifieds sites are operated by the German startup company Yalwa located in Wiesbaden, Germany. Locanto was launched in July 2006 with a local classifieds site for New York City. One month later, on August 21, 2006, the service was extended to the U.S. cities of Boston, Chicago, Los Angeles and San Francisco. As of 2007, every major U.S. city has its own accessible site for the Locanto classifieds service.
Locanto was created by the German start-up company, Yalwa. Klaus P. Gapp, CEO and founder of Yalwa, previously founded and operated OpusForum.org, a local classifieds site for the German speaking market. OpusForum.org was bought by eBay in 2005 and merged with its classifieds site Kijiji one year later.
Safety
In regards to internet safety, Locanto has established an independent blog on Safer Trading in which safety tips for online trading are shared with users.
Mobile and Apps
Since February 2010, the Locanto classifieds sites have also been available in mobile version for mobile web users. Browsing and searching classified ads as well as posting a free ad is enabled in the mobile version.
Adsdistrict.in mobile site has been blamed for copying Locanto mobile site.
In 2012, the Locanto iPhone App was launched and in 2014, the Locanto Android App was made available. In 2015, the Locanto Classifieds 2.0 iPhone app was released.
Criticism
In January 2010, several Indian media channels reported a story about Kannada actress Sanchita Padukone's pictures having been misused in a personals services ad on Locanto India, naming Locanto a "porn site".
While there is a dedicated version of this site for the Indian market over 60% of the traffic of the American version of the site comes from India.
In 2023 the Irish state broadcaster RTÉ investigated claims that accommodation wa
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https://en.wikipedia.org/wiki/Opaque%20set
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In discrete geometry, an opaque set is a system of curves or other set in the plane that blocks all lines of sight across a polygon, circle, or other shape. Opaque sets have also been called barriers, beam detectors, opaque covers, or (in cases where they have the form of a forest of line segments or other curves) opaque forests. Opaque sets were introduced by Stefan Mazurkiewicz in 1916, and the problem of minimizing their total length was posed by Frederick Bagemihl in 1959.
For instance, visibility through a unit square can be blocked by its four boundary edges, with length 4, but a shorter opaque forest blocks visibility across the square with length . It is unproven whether this is the shortest possible opaque set for the square, and for most other shapes this problem similarly remains unsolved. The shortest opaque set for any bounded convex set in the plane has length at most the perimeter of the set, and at least half the perimeter. For the square, a slightly stronger lower bound than half the perimeter is known. Another convex set whose opaque sets are commonly studied is the unit circle, for which the shortest connected opaque set has length . Without the assumption of connectivity, the shortest opaque set for the circle has length at least and at most .
Several published algorithms claiming to find the shortest opaque set for a convex polygon were later shown to be incorrect. Nevertheless, it is possible to find an opaque set with a guaranteed approximation ratio in linear time, or to compute the subset of the plane whose visibility is blocked by a given system of line segments in polynomial time.
Definitions
Every set in the plane blocks the visibility through a superset of , its coverage . consists of points for which all lines through the point intersect . If a given set forms a subset of the coverage of , then is said to be an opaque set, barrier, beam detector, or opaque cover for . If, additionally, has a special form, consisting of finitely
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https://en.wikipedia.org/wiki/Institute%20of%20Applied%20Physics%20and%20Computational%20Mathematics
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The Institute of Applied Physics and Computational Mathematics (IAPCM) was established in 1958 in Beijing in the People's Republic of China. The institution conducts research on nuclear warhead design computations for the Chinese Academy of Engineering Physics (CAEP) in Mianyang, Sichuan and focuses on applied theoretical research and on the study of fundamental theories. Its main research fields include: Theoretical physics, nuclear fusion, plasma physics, nuclear physics, atomic molecular physics, laser physics, fluid dynamics, applied mathematics, and arms control science and technology.
The Federal Bureau of Investigation has stated that IAPCM has targeted U.S. defense labs for industrial espionage.
From August 2012, the director of the institute was LI Hua.
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https://en.wikipedia.org/wiki/Atkinson%20dithering
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Atkinson dithering is a variant of Floyd-Steinberg dithering designed by Bill Atkinson at Apple Computer, and used in the original Macintosh computer.
Implementation
The algorithm achieves dithering using error diffusion, meaning it pushes (adds) the residual quantization error of a pixel onto its neighboring pixels, to be dealt with later. It spreads the debt out according to the distribution (shown as a map of the neighboring pixels):
The pixel indicated with a star (*) indicates the pixel currently being scanned, and the blank pixels are the previously scanned pixels.
The algorithm scans the image from left to right, top to bottom, quantizing pixel values one by one. Each time the quantization error is transferred to the neighboring pixels, while not affecting the pixels that already have been quantized. Hence, if a number of pixels have been rounded downwards, it becomes more likely that the next pixel is rounded upwards, such that on average, the quantization error is reduced.
Unlike Floyd-Steinberg dithering, only 3/4 of the error is diffused outward. This leads to a more localized dither, at the cost of lower performance on near-white and near-black areas, but the increase in contrast on those areas may be regarded as more visually desirable for some purposes.
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https://en.wikipedia.org/wiki/Circular%20error%20probable
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In the military science of ballistics, circular error probable (CEP) (also circular error probability or circle of equal probability) is a measure of a weapon system's precision. It is defined as the radius of a circle, centered on the mean, whose perimeter is expected to enclose the landing points of 50% of the rounds; said otherwise, it is the median error radius. That is, if a given munitions design has a CEP of 100 m, when 100 munitions are targeted at the same point, 50 will fall within a circle with a radius of 100 m around their average impact point. (The distance between the target point and the average impact point is referred to as bias.)
There are associated concepts, such as the DRMS (distance root mean square), which is the square root of the average squared distance error, and R95, which is the radius of the circle where 95% of the values would fall in.
The concept of CEP also plays a role when measuring the accuracy of a position obtained by a navigation system, such as GPS or older systems such as LORAN and Loran-C.
Concept
The original concept of CEP was based on a circular bivariate normal distribution (CBN) with CEP as a parameter of the CBN just as μ and σ are parameters of the normal distribution. Munitions with this distribution behavior tend to cluster around the mean impact point, with most reasonably close, progressively fewer and fewer further away, and very few at long distance. That is, if CEP is n metres, 50% of shots land within n metres of the mean impact, 43.7% between n and 2n, and 6.1% between 2n and 3n metres, and the proportion of shots that land farther than three times the CEP from the mean is only 0.2%.
CEP is not a good measure of accuracy when this distribution behavior is not met. Precision-guided munitions generally have more "close misses" and so are not normally distributed. Munitions may also have larger standard deviation of range errors than the standard deviation of azimuth (deflection) errors, resulting in an el
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https://en.wikipedia.org/wiki/Last%20geometric%20statement%20of%20Jacobi
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In differential geometry the last geometric statement of Jacobi is a conjecture named after Carl Gustav Jacob Jacobi, which states:
Every caustic from any point on an ellipsoid other than umbilical points has exactly four cusps.
Numerical experiments had indicated the statement is true before it was proven rigorously in 2004 by Itoh and Kiyohara. It has since been extended to a wider class of surfaces beyond the ellipsoid.
See also
Four-vertex theorem
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https://en.wikipedia.org/wiki/Schl%C3%B6milch%27s%20series
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Schlömilch's series is a Fourier series type expansion of twice continuously differentiable function in the interval in terms of the Bessel function of the first kind, named after the German mathematician Oskar Schlömilch, who derived the series in 1857. The real-valued function has the following expansion:
where
Examples
Some examples of Schlömilch's series are the following:
Null functions in the interval can be expressed by Schlömilch's Series, , which cannot be obtained by Fourier Series. This is particularly interesting because the null function is represented by a series expansion in which not all the coefficients are zero. The series converges only when ; the series oscillates at and diverges at . This theorem is generalized so that when and and also when and . These properties were identified by Niels Nielsen.
If are the cylindrical polar coordinates, then the series is a solution of Laplace equation for .
See also
Kapteyn series
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https://en.wikipedia.org/wiki/List%20of%20conversion%20factors
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This article gives a list of conversion factors for several physical quantities. A number of different units (some only of historical interest) are shown and expressed in terms of the corresponding SI unit.
Conversions between units in the metric system are defined by their prefixes (for example, 1 kilogram = 1000 grams, 1 milligram = 0.001 grams) and are thus not listed in this article. Exceptions are made if the unit is commonly known by another name (for example, 1 micron = 10−6 metre). Within each table, the units are listed alphabetically, and the SI units (base or derived) are highlighted.
The following quantities are considered: length, area, volume, plane angle, solid angle, mass, density, time, frequency, velocity, volumetric flow rate, acceleration, force, pressure (or mechanical stress), torque (or moment of force), energy, power (or heat flow rate), action, dynamic viscosity, kinematic viscosity, electric current, electric charge, electric dipole, electromotive force (or electric potential difference), electrical resistance, capacitance, magnetic flux, magnetic flux density, inductance, temperature, information entropy, luminous intensity, luminance, luminous flux, illuminance, radiation.
Length
Area
Volume
Plane angle
Solid angle
Mass
Notes:
See Weight for detail of mass/weight distinction and conversion.
Avoirdupois is a system of mass based on a pound of 16 ounces, while Troy weight is the system of mass where 12 troy ounces equals one troy pound.
The symbol is used to denote standard gravity in order to avoid confusion with the (upright) g symbol for gram.
Density
Time
Frequency
Speed or velocity
A velocity consists of a speed combined with a direction; the speed part of the velocity takes units of speed.
Flow (volume)
Acceleration
Force
Pressure or mechanical stress
Torque or moment of force
Energy
Power or heat flow rate
Action
Dynamic viscosity
Kinematic viscosity
Electric current
Electric charge
Electric dipole
Elec
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https://en.wikipedia.org/wiki/Poly1305
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Poly1305 is a universal hash family designed by Daniel J. Bernstein for use in cryptography.
As with any universal hash family, Poly1305 can be used as a one-time message authentication code to authenticate a single message using a secret key shared between sender and recipient,
similar to the way that a one-time pad can be used to conceal the content of a single message using a secret key shared between sender and recipient.
Originally Poly1305 was proposed as part of Poly1305-AES,
a Carter–Wegman authenticator
that combines the Poly1305 hash with AES-128 to authenticate many messages using a single short key and distinct message numbers.
Poly1305 was later applied with a single-use key generated for each message using XSalsa20 in the NaCl crypto_secretbox_xsalsa20poly1305 authenticated cipher,
and then using ChaCha in the ChaCha20-Poly1305 authenticated cipher
deployed in TLS on the internet.
Description
Definition of Poly1305
Poly1305 takes a 16-byte secret key and an -byte message and returns a 16-byte hash .
To do this, Poly1305:
Interprets as a little-endian 16-byte integer.
Breaks the message into consecutive 16-byte chunks.
Interprets the 16-byte chunks as 17-byte little-endian integers by appending a 1 byte to every 16-byte chunk, to be used as coefficients of a polynomial.
Evaluates the polynomial at the point modulo the prime .
Reduces the result modulo encoded in little-endian return a 16-byte hash.
The coefficients of the polynomial , where , are:
with the exception that, if , then:
The secret key is restricted to have the bytes , i.e., to have their top four bits clear; and to have the bytes , i.e., to have their bottom two bits clear.
Thus there are distinct possible values of .
Use as a one-time authenticator
If is a secret 16-byte string interpreted as a little-endian integer, then
is called the authenticator for the message .
If a sender and recipient share the 32-byte secret key in advance, chosen uniformly at random, th
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https://en.wikipedia.org/wiki/Tommaso%20Toffoli
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Tommaso Toffoli () is an Italian-American professor of electrical and computer engineering at Boston University where he joined the faculty in 1995. He has worked on cellular automata and the theory of artificial life (with Edward Fredkin and others), and is known for the invention of the Toffoli gate.
Early life and career
He was born in June, 1943 in Montereale Valcellina, in northeastern Italy, to Francesco and Valentina (Saveri) Toffoli and was raised in Rome. He received his laurea in physics (equivalent to a Master's degree) from the University of Rome La Sapienza in 1967.
Toffoli moved to the United States in 1969.
In 1976 he received a Ph.D. in computer and communication science from the University of Michigan, then in 1978 he joined the faculty of Massachusetts Institute of Technology as a principal research scientist, where he remained until 1995, when he joined the faculty of Boston University.
Books
Cellular Automata Machines: A New Environment for Modeling, MIT Press (1987), with Norman Margolus. .
See also
Billiard-ball computer
Block cellular automaton
CAM-6
Computronium
Critters (cellular automaton)
Programmable matter
Reversible cellular automaton
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https://en.wikipedia.org/wiki/NcRNA%20therapy
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A majority of the human genome is made up of non-protein coding DNA. It infers that such sequences are not commonly employed to encode for a protein. However, even though these regions do not code for protein, they have other functions and carry necessary regulatory information.They can be classified based on the size of the ncRNA. Small noncoding RNA is usually categorized as being under 200 bp in length, whereas long noncoding RNA is greater than 200bp. In addition, they can be categorized by their function within the cell; Infrastructural and Regulatory ncRNAs. Infrastructural ncRNAs seem to have a housekeeping role in translation and splicing and include species such as rRNA, tRNA, snRNA.Regulatory ncRNAs are involved in the modification of other RNAs.
RNA Classification
Long non-coding RNA
Long non-coding RNA (LncRNA) are a type of RNA which is usually defined as transcripts which are greater than 200 base-pairs in length and not translated into proteins. This limitation distinguishes lncRNA from small non-coding RNAs which encompasses microRNAs (miRNAs), small interfering RNAs (siRNAs), Piwi-interacting RNAs (piRNAs), small nucleolar RNAs (snoRNAs), and other short RNAs. Long non-coding RNAs include lincRNAs, intronic ncRNAs, circular and linear ncRNA.
Long intergenic Non-coding RNA
Long intergenic Non-coding RNA (LincRNA) is defined as RNA transcripts that are longer than 200 nucleotides. These RNAs must not have open reading frames that encode proteins. The term “intergenic” refers to the identification of these transcripts from regions of the genome that do not contain protein-encoding genes. LncRNAs also contain promoter - or enhancer-associated RNAs that are gene proximal and can be either in the sense or antisense orientation.
Circular RNA
Circular RNA (CircRNA) are a novel class of endogenous noncoding RNAs and are characterized by their covalently closed loop structures. This class of ncRNA does not have a 5’ cap or 3’ Poly A tail. It has be
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https://en.wikipedia.org/wiki/Crespi%20effect
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The Crespi effect is a behavioural contrast phenomenon observed in classical conditioning in which a conditioned response changes disproportionately to a suddenly changed reinforcement. It was first observed in rats by American psychologist Leo P. Crespi in 1942.
He found that in a repeatedly carried out task such as finding food in a maze, the running speed of the rat is proportional to the size of the reward it obtained on the previous trial. The more food reward that was given to it last time upon completion of the task, the faster it will run when attempting to complete the same task. The effect also works in reverse: when rats were shifted from a larger to a smaller reward, they ran more slowly than the control rats that had always received the small reward.
It is important to note that the size of the reward has little or no influence on the speed of learning, but that it does have an influence on the performance of tasks already learned.
Scholars have been only partially able to replicate Crespi's studies, which remains controversial.
See also
Contrast effect
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https://en.wikipedia.org/wiki/List%20of%20possible%20dwarf%20planets
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The number of dwarf planets in the Solar System is unknown. Estimates have run as high as 200 in the Kuiper belt and over 10,000 in the region beyond.
However, consideration of the surprisingly low densities of many large trans-Neptunian objects suggests that the number of dwarf planets may be much lower, perhaps only eight or nine among bodies known so far. The International Astronomical Union (IAU) defines dwarf planets as being in hydrostatic equilibrium, and notes five bodies in particular: in the inner Solar System and four in the trans-Neptunian region: , , , and . Only Pluto and Ceres have been confirmed to be in hydrostatic equilibrium, due to the results of the New Horizons and Dawn missions. Eris is generally assumed to be a dwarf planet because it is similar in size to Pluto and even more massive. Haumea and Makemake were accepted as dwarf planets by the IAU for naming purposes and will keep their names if it turns out they are not dwarf planets. Smaller trans-Neptunian objects have been called dwarf planets if they appear to be solid bodies, which is a prerequisite for hydrostatic equilibrium: planetologists generally include at least , , , and sometimes . (In practice the requirement for hydrostatic equilibrium is always loosened anyway, even by the IAU, as otherwise even Mercury would not be a planet.)
Limiting values
Beside directly orbiting the Sun, the qualifying feature of a dwarf planet is that it have "sufficient mass for its self-gravity to overcome rigid-body forces so that it assumes a hydrostatic equilibrium (nearly round) shape". Current observations are generally insufficient for a direct determination as to whether a body meets this definition. Often the only clues for trans-Neptunian objects (TNO) is a crude estimate of their diameters and albedos. Icy satellites as large as 1,500 km in diameter have proven to not be in equilibrium, whereas dark objects in the outer solar system often have low densities that imply they are not even s
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https://en.wikipedia.org/wiki/V.%20Lakshmibai
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Venkatraman Lakshmibai is an Indian mathematician who is a professor emerita of mathematics at Northeastern University in Boston. Her research concerns algebraic geometry, the theory of algebraic groups, and representation theory, including in particular the theory of flag varieties and Schubert varieties.
Lakshmibai earned her PhD in 1976 from the Tata Institute of Fundamental Research.
With Sara Billey she is the co-author of the monograph Singular Loci of Schubert Varieties (Progress in Mathematics 182, Birkhäuser, 2000).
She has also co-authored two monographs with Justin Brown: Flag Varieties: An Interplay of Geometry, Combinatorics, and Representation Theory (Texts and Readings in Mathematics 53, Hindustan Book Agency, 2009) and The Grassmannian Variety: Geometric and Representation-Theoretic Aspects (Developments in Mathematics 42, Springer, 2015).
In 2012 she was selected as one of the inaugural fellows of the American Mathematical Society.
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https://en.wikipedia.org/wiki/Immobilized%20whole%20cell
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The immobilized whole cell system is an alternative to enzyme immobilization. Unlike enzyme immobilization, where the enzyme is attached to a solid support (such as calcium alginate or activated PVA or activated PEI), in immobilized whole cell systems, the target cell is immobilized. Such methods may be implemented when the enzymes required are difficult or expensive to extract, an example being intracellular enzymes. Also, if a series of enzymes are required in the reaction; whole cell immobilization may be used for convenience. This is only done on a commercial basis when the need for the product is more justified.
Multiple enzymes may be introduced into the reaction, thus eliminating the need for immobilization of multiple enzymes. Furthermore, intracellular enzymes need not be extracted prior to the reaction; they may be used directly. However, some enzymes may be used for the metabolic needs of the cell, leading to reduced yield of the cell.
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https://en.wikipedia.org/wiki/Adapter%20molecule%20crk
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Adapter molecule crk also known as proto-oncogene c-Crk is a protein that in humans is encoded by the CRK gene.
The CRK protein participates in the Reelin signaling cascade downstream of DAB1.
Function
Adapter molecule crk is a member of an adapter protein family that binds to several tyrosine-phosphorylated proteins. This protein has several SH2 and SH3 domains (src-homology domains) and is involved in several signaling pathways, recruiting cytoplasmic proteins in the vicinity of tyrosine kinase through SH2-phosphotyrosine interaction. The N-terminal SH2 domain of this protein functions as a positive regulator of transformation whereas the C-terminal SH3 domain functions as a negative regulator of transformation. Two alternative transcripts encoding different isoforms with distinct biological activity have been described.
Crk together with CrkL participates in the Reelin signaling cascade downstream of DAB1.
v-Crk, a transforming oncoprotein from avian sarcoma viruses, is a fusion of viral "gag" protein with the SH2 and SH3 domains of cellular Crk. The name Crk is from "CT10 Regulator of Kinase" where CT10 is the avian virus from which was isolated a protein, lacking kinase domains, but capable of stimulating phosphorylation of tyrosines in cells.
Crk should not be confused with Src, which also has cellular (c-Src) and viral (v-Src) forms and is involved in some of the same signaling pathways but is a protein tyrosine-kinase.
Interactions
CRK (gene) has been shown to interact with:
BCAR1,
Cbl gene,
Dock180,
EPS15,
Epidermal growth factor receptor,
Grb2,
IRS4,
MAP4K1,
MAPK8,
NEDD9,
PDGFRA,
PDGFRB,
PTK2,
Paxillin
RAPGEF1,
RICS,
SH3KBP1, and
SOS1.
See also
CrkL, "Crk-like" protein
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https://en.wikipedia.org/wiki/HRU%20%28security%29
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The HRU security model (Harrison, Ruzzo, Ullman model) is an operating system level computer security model which deals with the integrity of access rights in the system. It is an extension of the Graham-Denning model, based around the idea of a finite set of procedures being available to edit the access rights of a subject on an object . It is named after its three authors, Michael A. Harrison, Walter L. Ruzzo and Jeffrey D. Ullman.
Along with presenting the model, Harrison, Ruzzo and Ullman also discussed the possibilities and limitations of proving the safety of systems using an algorithm.
Description of the model
The HRU model defines a protection system consisting of a set of generic rights R and a set of commands C. An instantaneous description of the system is called a configuration and is defined as a tuple of current subjects , current objects and an access matrix . Since the subjects are required to be part of the objects, the access matrix contains one row for each subject and one column for each subject and object. An entry for subject and object is a subset of the generic rights .
The commands are composed of primitive operations and can additionally have a list of pre-conditions that require certain rights to be present for a pair of subjects and objects.
The primitive requests can modify the access matrix by adding or removing access rights for a pair of subjects and objects and by adding or removing subjects or objects. Creation of a subject or object requires the subject or object not to exist in the current configuration, while deletion of a subject or object requires it to have existed prior to deletion. In a complex command, a sequence of operations is executed only as a whole. A failing operation in a sequence makes the whole sequence fail, a form of database transaction.
Discussion of safety
Harrison, Ruzzo and Ullman discussed whether there is an algorithm that takes an arbitrary initial configuration and answers the following que
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https://en.wikipedia.org/wiki/External%20sorting
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External sorting is a class of sorting algorithms that can handle massive amounts of data. External sorting is required when the data being sorted do not fit into the main memory of a computing device (usually RAM) and instead they must reside in the slower external memory, usually a disk drive. Thus, external sorting algorithms are external memory algorithms and thus applicable in the external memory model of computation.
External sorting algorithms generally fall into two types, distribution sorting, which resembles quicksort, and external merge sort, which resembles merge sort. External merge sort typically uses a hybrid sort-merge strategy. In the sorting phase, chunks of data small enough to fit in main memory are read, sorted, and written out to a temporary file. In the merge phase, the sorted subfiles are combined into a single larger file.
Model
External sorting algorithms can be analyzed in the external memory model. In this model, a cache or internal memory of size and an unbounded external memory are divided into blocks of size , and the running time of an algorithm is determined by the number of memory transfers between internal and external memory. Like their cache-oblivious counterparts, asymptotically optimal external sorting algorithms achieve a running time (in Big O notation) of .
External merge sort
One example of external sorting is the external merge sort algorithm, which is a K-way merge algorithm. It sorts chunks that each fit in RAM, then merges the sorted chunks together.
The algorithm first sorts items at a time and puts the sorted lists back into external memory. It then recursively does a -way merge on those sorted lists. To do this merge, elements from each sorted list are loaded into internal memory, and the minimum is repeatedly outputted.
For example, for sorting 900 megabytes of data using only 100 megabytes of RAM:
Read 100 MB of the data in main memory and sort by some conventional method, like quicksort.
Write the s
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https://en.wikipedia.org/wiki/ATAPI
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ATAPI (ATA Packet Interface) is a protocol used with the Parallel ATA (IDE) and Serial ATA standards so that a greater variety of devices can be connected to a computer than with the ATA command set alone. It carries SCSI commands and responses through the ATA interface.
ATAPI devices include CD-ROM and DVD-ROM drives, tape drives, magneto-optical drives, and large-capacity floppy drives such as the Zip drive and SuperDisk drive.
History
ATA was originally designed for, and worked only with, hard disks and devices that could emulate them. A group called the Small Form Factor committee (SFF) introduced ATAPI to be used for a variety of other devices that require functions beyond those necessary for hard disks. For example, any removable media device needs a "media eject" command, and a way for the host to determine whether the media is present, and these were not provided in the ATA protocol.
The Small Form Factor committee approached this problem by defining ATAPI as part of the fourth generation of ATA. ATAPI carries SCSI commands through ATA, so ATAPI devices are "speaking SCSI" other than at the electrical interface. In fact, some early ATAPI devices were simply SCSI devices with an ATA/ATAPI to SCSI protocol converter added on. The SCSI commands and responses are embedded in "packets" (hence "ATA Packet Interface") for transmission on the ATA cable. This interfaces ATA with any device class for which a SCSI command set has been defined. ATAPI devices are also "speaking ATA" because the ATA physical interface and protocol are still being used to send the packets.
The Direct Memory Access feature for the ATA interface was introduced along with ATAPI.
Specification
The SCSI commands and responses used by each class of ATAPI device (CD-ROM, tape, etc.) are described in other documents or specifications specific to those device classes and are not within ATA/ATAPI or the T13 committee's purview. One commonly used set is defined in the MMC SCSI command set.
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https://en.wikipedia.org/wiki/Kitrinoviricota
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Kitrinoviricota is a phylum of RNA viruses that includes all positive-strand RNA viruses that infect eukaryotes and are not members of the phylum Pisuviricota or Lenarviricota. The name of the group derives from Greek κίτρινος (kítrinos), which means yellow (a reference to yellow fever virus), and -viricota, which is the suffix for a virus phylum.
Classes
The following classes are recognized:
Alsuviricetes
Flasuviricetes
Magsaviricetes
Tolucaviricetes
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https://en.wikipedia.org/wiki/Tinker%20Bell%20%28Disney%20character%29
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Tinker Bell is a fictional fairy based on the same name character created by Scottish novelist and playwright J. M. Barrie, and one of the most popular characters adapted for film and television by The Walt Disney Company. She first appear in the 1953 Disney animated film, Peter Pan, and has since become a widely recognized unofficial mascot of Disney, next to the company's official mascot Mickey Mouse. She is generally known as "a symbol of 'the magic of Disney'".
Adaptation and development by Disney
As with previous Disney animated features, a live-action version was filmed to serve as an aid to animators with the actors performing to a prerecorded dialogue track. Actress Margaret Kerry received a call to audition to serve as the live-action reference for Tinker Bell.
There is a myth that the original animated version of Tinker Bell was modelled after Marilyn Monroe. However, Disney animator Marc Davis's primary reference was Margaret Kerry. He illustrated Tinker Bell as an attractive, blonde blue-eyed young white female, with an exaggerated hourglass figure. She is dressed in a bright green strapless dress and wears green slippers with white puffs. A trail of pixie dust follows her when she moves.
Davis' first model for the character was 19-year-old Ginni Mack, who had previously been used as the face of the company's Ink and Paint Department for promotional material, and served as a facial expression model. For the character's body, Davis worked at first with Kathryn Beaumont, who had served as his model for Alice. Looking for someone more "adult" who was "sexy" and shapely they turned to Margaret Kerry, who had been named “World’s Most Beautiful Legs” in Hollywood in 1949, and whose experience as a dancer helped convey the character's emotions.
Since 1954, Tinker Bell has featured as a hostess for much of Disney's live-action television programming and in every Disney film advertisements flying over Disneyland with her magic wand and her fairy dust, beginn
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https://en.wikipedia.org/wiki/Outline%20of%20control%20engineering
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The following outline is provided as an overview of and topical guide to control engineering:
Control engineering – engineering discipline that applies control theory to design systems with desired behaviors. The practice uses sensors to measure the output performance of the device being controlled and those measurements can be used to give feedback to the input actuators that can make corrections toward desired performance. When a device is designed to perform without the need of human inputs for correction it is called automatic control (such as cruise control for regulating a car's speed).
Branches
Adaptive control
Control theory – interdisciplinary branch of engineering and mathematics that deals with the behavior of dynamical systems. The usual objective of control theory is to calculate solutions for the proper corrective action from the controller that result in system stability.
Digital control
Energy-shaping control
Fuzzy control
Hybrid control
Intelligent control
Model predictive control
Multivariable control
Neural control
Nonlinear control
Optimal control
Real-time control
Robust control
Stochastic control
Mathematical concepts
Complex analysis
Differential equations
Linear algebra
Mathematical system theory
Matrices
Real analysis
Variational calculus
System properties
Bode plot
Block diagram
Closed-loop transfer function
Controllability
Fourier transform
Frequency response
Laplace transform
Negative feedback
Observability
Performance
Positive feedback
Root locus method
Servomechanism
Signal-flow graph
State space representation
Stability theory
Steady state analysis & design
System dynamics
Transfer function
Digital control
Discrete-time signal
Digital signal processing
Quantization
Real-time software
sampled data
System identification
Z transform
Advanced techniques
Artificial neural networks
Coefficient diagram method
Control reconfiguration
Distributed parameter systems
Fractional-order cont
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https://en.wikipedia.org/wiki/Angle-sensitive%20pixel
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An angle-sensitive pixel (ASP) is a CMOS sensor with a sensitivity to incoming light that is sinusoidal in incident angle.
Principles of operation
ASPs are typically composed of two gratings (a diffraction grating and an analyzer grating) above a single photodiode. ASPs exploit the moire effect and the Talbot effect to gain their sinusoidal light sensitivity. According to the moire effect, if light acted as a particle, at certain incident angles the gaps in the diffraction and analyzer gratings line up, while at other incident angles light passed by the diffraction grating is blocked by the analyzer grating. The amount of light reaching the photodiode would be proportional to a sinusoidal function of incident angle, as the two gratings come in and out of phase with each other with shifting incident angle. The wave nature of light becomes important at small scales such as those in ASPs, meaning a pure-moire model of ASP function is insufficient. However, at half-integer multiples of the Talbot depth, the periodicity of the diffraction grating is recapitulated, and the moire effect is rescued. By building ASPs where the vertical separation between the gratings is approximately equal to a half-integer multiple of the Talbot depth, the sinusoidal sensitivity with incident angle is observed.
Applications
ASPs can be used in miniature imaging devices. They do not require any focusing elements to achieve sinusoidal incident angle sensitivity, meaning that they can be deployed without a lens to image the near field, or the far field using a Fourier-complete planar Fourier capture array. They can also be used in conjunction with a lens, in which case they perform a depth-sensitive, physics-based wavelet transform of the far-away scene, allowing single-lens 3D photography similar to that of the Lytro camera.
See also
Planar Fourier capture array
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https://en.wikipedia.org/wiki/Test%20data
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Test data plays a crucial role in software development by providing inputs that are used to verify the correctness, performance, and reliability of software systems. Test data encompasses various types, such as positive and negative scenarios, edge cases, and realistic user scenarios, and it aims to exercise different aspects of the software to uncover bugs and validate its behavior. By designing and executing test cases with appropriate test data, developers can identify and rectify defects, improve the quality of the software, and ensure it meets the specified requirements. Moreover, test data can also be used for regression testing to validate that new code changes or enhancements do not introduce any unintended side effects or break existing functionalities. Overall, the effective utilization of test data in software development significantly contributes to the production of reliable and robust software systems.
Background
Some data may be used in a confirmatory way, typically to verify that a given set of inputs to a given function produces some expected result. Other data may be used in order to challenge the ability of the program to respond to unusual, extreme, exceptional, or unexpected input.
Test data may be produced in a focused or systematic way (as is typically the case in domain testing), or by using other, less-focused approaches (as is typically the case in high-volume randomized automated tests). Test data may be produced by the tester, or by a program or function that aids the tester. Test data may be recorded for reuse or used only once. Test data can be created manually, by using data generation tools (often based on randomness), or be retrieved from an existing production environment. The data set can consist of synthetic (fake) data, but preferably it consists of representative (real) data.
Limitations
Due to privacy rules and regulations like GDPR, PCI and HIPAA it is not allowed to use privacy sensitive personal data for testing. But an
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https://en.wikipedia.org/wiki/Symmetric%20tensor
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In mathematics, a symmetric tensor is a tensor that is invariant under a permutation of its vector arguments:
for every permutation σ of the symbols Alternatively, a symmetric tensor of order r represented in coordinates as a quantity with r indices satisfies
The space of symmetric tensors of order r on a finite-dimensional vector space V is naturally isomorphic to the dual of the space of homogeneous polynomials of degree r on V. Over fields of characteristic zero, the graded vector space of all symmetric tensors can be naturally identified with the symmetric algebra on V. A related concept is that of the antisymmetric tensor or alternating form. Symmetric tensors occur widely in engineering, physics and mathematics.
Definition
Let V be a vector space and
a tensor of order k. Then T is a symmetric tensor if
for the braiding maps associated to every permutation σ on the symbols {1,2,...,k} (or equivalently for every transposition on these symbols).
Given a basis {ei} of V, any symmetric tensor T of rank k can be written as
for some unique list of coefficients (the components of the tensor in the basis) that are symmetric on the indices. That is to say
for every permutation σ.
The space of all symmetric tensors of order k defined on V is often denoted by Sk(V) or Symk(V). It is itself a vector space, and if V has dimension N then the dimension of Symk(V) is the binomial coefficient
We then construct Sym(V) as the direct sum of Symk(V) for k = 0,1,2,...
Examples
There are many examples of symmetric tensors. Some include, the metric tensor, , the Einstein tensor, and the Ricci tensor, .
Many material properties and fields used in physics and engineering can be represented as symmetric tensor fields; for example: stress, strain, and anisotropic conductivity. Also, in diffusion MRI one often uses symmetric tensors to describe diffusion in the brain or other parts of the body.
Ellipsoids are examples of algebraic varieties; and so, for general rank,
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https://en.wikipedia.org/wiki/Green%20flag
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A green flag has various meanings.
National flags
The Flag of the Great Socialist People's Libyan Arab Jamahiriya was a plain green flag.
The Flag of Saudi Arabia has a field of green, which represents Islam.
Irish nationalism was traditionally represented with a green flag. The current flag of Ireland is a tricolour with green representing the Irish Catholics, orange representing the Irish Protestants, and white in the middle to represent peace.
The former Flag of Mauritania.
Various green-striped American flags flew during the Revolutionary War, with green representing the 'color of hope'.
Other
A green flag is part of a set of racing flags and indicates the beginning or resumption of an auto race.
The actual flags flown in parks and gardens that have received the Green Flag Award.
On rail transport in Great Britain and Ireland, green flags are sometimes used (less often than in the past) by railway guards as a signal to engine drivers that they can proceed.
See also
White flag
Red flag (disambiguation)
Action Party (Italy)
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https://en.wikipedia.org/wiki/Killian%27s%20dehiscence
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Killian's dehiscence (also known as Killian's triangle) is a triangular area in the wall of the pharynx between the cricopharyngeus and thyropharyngeus which are the two parts of the inferior constrictors(also see Pharyngeal pouch). It can be seen as a locus minoris resistentiae.
Similar triangular area between circular fibres of cricopharyngeus and longitudinal fibres of esophagus is Lamier's triangle or Lamier-hackermann's area.
Clinical significance
It represents a potentially weak spot where a pharyngoesophageal diverticulum (Zenker's diverticulum) is more likely to occur.
Eponym
It is named after the German ENT surgeon Gustav Killian.
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https://en.wikipedia.org/wiki/History%20of%20probability
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Probability has a dual aspect: on the one hand the likelihood of hypotheses given the evidence for them, and on the other hand the behavior of stochastic processes such as the throwing of dice or coins. The study of the former is historically older in, for example, the law of evidence, while the mathematical treatment of dice began with the work of Cardano, Pascal, Fermat and Christiaan Huygens between the 16th and 17th century.
Probability deals with random experiments with a known distribution, Statistics deals wirh inference from the data about the unknown distribution.
Etymology
Probable and probability and their cognates in other modern languages derive from medieval learned Latin probabilis, deriving from Cicero and generally applied to an opinion to mean plausible or generally approved. The form probability is from Old French (14 c.) and directly from Latin (nominative ) "credibility, probability," from (see probable).
The mathematical sense of the term is from 1718. In the 18th century, the term chance was also used in the mathematical sense of "probability" (and probability theory was called Doctrine of Chances). This word is ultimately from Latin cadentia, i.e. "a fall, case".
The English adjective likely is of Germanic origin, most likely from Old Norse (Old English had with the same sense), originally meaning "having the appearance of being strong or able" "having the similar appearance or qualities", with a meaning of "probably" recorded mid-15c. The derived noun likelihood had a meaning of "similarity, resemblance" but took on a meaning of "probability" from the mid 15th century. The meaning "something likely to be true" is from 1570s.
Origins
Ancient and medieval law of evidence developed a grading of degrees of proof, credibility, presumptions and half-proof to deal with the uncertainties of evidence in court.
In Renaissance times, betting was discussed in terms of odds such as "ten to one" and maritime insurance premiums were estimated ba
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https://en.wikipedia.org/wiki/Journal%20of%20the%20Royal%20Statistical%20Society
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The Journal of the Royal Statistical Society is a peer-reviewed scientific journal of statistics. It comprises three series and is published by Oxford University Press for the Royal Statistical Society.
History
The Statistical Society of London was founded in 1834, but would not begin producing a journal for four years. From 1834 to 1837, members of the society would read the results of their studies to the other members, and some details were recorded in the proceedings. The first study reported to the society in 1834 was a simple survey of the occupations of people in Manchester, England. Conducted by going door-to-door and inquiring, the study revealed that the most common profession was mill-hands, followed closely by weavers.
When founded, the membership of the Statistical Society of London overlapped almost completely with the statistical section of the British Association for the Advancement of Science. In 1837 a volume of Transactions of the Statistical Society of London were written, and in May 1838 the society began its journal. The first editor-in-chief of the journal was Rawson W. Rawson. In the early days of the society and the journal, there was dispute over whether or not opinions should be expressed, or merely the numbers. The symbol of the society was a wheatsheaf, representing a bundle of facts, and the motto Aliis exterendum, Latin for "to be threshed out by others." Many early members chafed under this prohibition, and in 1857 the motto was dropped.
From 1838 to 1886, the journal was published as the Journal of the Statistical Society of London (). In 1887 it was renamed the Journal of the Royal Statistical Society () when the society was granted a Royal Charter.
On its centenary in 1934, the society inaugurated a Supplement to the Journal of the Royal Statistical Society to publish work on industrial and agricultural applications. In 1948 the society reorganised its journals and the main journal became the Journal of the Royal Statistical
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https://en.wikipedia.org/wiki/Nerve%20fascicle
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A nerve fascicle, is a bundle of nerve fibers belonging to a nerve in the peripheral nervous system. A nerve fascicle is also called a fasciculus, as is a nerve tract in the central nervous system.
A nerve fascicle is enclosed by perineurium, a layer of fascial connective tissue. Each enclosed nerve fiber in the fascicle is enclosed by a connective tissue layer of endoneurium. Bundles of nerve fascicles are called fasciculi and are constituents of a nerve trunk. A main nerve trunk may contain a great many fascicles enclosing many thousands of axons.
In the central nervous system a bundle of nerve fibers is called a nerve tract, and in neuroanatomy different tracts in the spinal cord are bundled into fasciculi such as the medial longitudinal fasciculus. In the spinal cord fasciculi are bundled into columns called funiculi such as the anterior funiculus.
See also
Epineurium
Nervous tissue
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https://en.wikipedia.org/wiki/Ryll-Nardzewski%20fixed-point%20theorem
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In functional analysis, a branch of mathematics, the Ryll-Nardzewski fixed-point theorem states that if is a normed vector space and is a nonempty convex subset of that is compact under the weak topology, then every group (or equivalently: every semigroup) of affine isometries of has at least one fixed point. (Here, a fixed point of a set of maps is a point that is fixed by each map in the set.)
This theorem was announced by Czesław Ryll-Nardzewski. Later Namioka and Asplund gave a proof based on a different approach. Ryll-Nardzewski himself gave a complete proof in the original spirit.
Applications
The Ryll-Nardzewski theorem yields the existence of a Haar measure on compact groups.
See also
Fixed-point theorems
Fixed-point theorems in infinite-dimensional spaces
Markov-Kakutani fixed-point theorem - abelian semigroup of continuous affine self-maps on compact convex set in a topological vector space has a fixed point
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https://en.wikipedia.org/wiki/Tachymetric%20anti-aircraft%20fire%20control%20system
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A tachymetric anti-aircraft fire control system generates target position, speed, direction, and rate of target range change, by computing these parameters directly from measured data.
The target's range, height and observed bearing data are fed into a computer which uses the measured change in range, height and bearing from successive observations of the target to compute the true range, direction, speed and rate of climb or descent of the target. The computer then calculates the required elevation and bearing of the AA guns to hit the target based upon its predicted movement.
The computers were at first entirely mechanical analog computers utilizing gears and levers to physically perform the calculations of protractors and slide rules, using moving graph charts and markers to provide an estimate of speed and position. Variation of target position over time was accomplished with constant-drive motors to run the mechanical simulation.
The term tachymetric should more properly be spelled as "tachometric" which comes from the Greek "takhos" = speed, and "metric" = measure, hence tachometric, to measure speed.
An alternative, non-tachometric, gonometric method of AA prediction is for specially trained observers to estimate the course and speed of the target manually and feed these estimates, along with the measured bearing and range data, into the AA fire control computer which then generates change of bearing rate and change of range data, and passes them back to the observer, typically by a "follow the pointer", indicator of predicted target elevation and bearing or by remote power control of the observer's optical instruments. The observer then corrects the estimate, creating a feed back loop, by comparing the observed target motion against the computer generated motion of his optical sights. When the sights stay on the target, the estimated speed, range, and change of rate data can be considered correct.
An example of tachometric AA fire control would be the
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https://en.wikipedia.org/wiki/4DCT
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Four-dimensional computed tomography (4DCT) is a type of CT scanning which records multiple images over time. It allows playback of the scan as a video, so that physiological processes can be observed and internal movement can be tracked. The name is derived from the addition of time (as the fourth dimension) to traditional 3D computed tomography. Alternatively, the phase of a particular process, such as respiration, may be considered the fourth dimension.
Fluoroscopy is a similar technique to 4DCT, however it refers to the introduction of a time element to 2D planar radiography, rather than to 3D CT.
Applications
Radiotherapy
4DCT is used in radiation therapy planning to reduce doses to healthy organs such as the heart or lungs. Most radiation therapy is planned using the results of a 3D CT scan. A 3D scan largely presents a snapshot of the body at a particular point in time, however due to the time of the acquisition, in which the patient is likely to have moved in some way (even if only breathing), there will be an element of blurring or averaging in the 3D scan. When it comes to treatment planning, this motion can mean there is less accuracy in the positioning of treatment beams, and reduce the likelihood of a repeatable set-up on the linear accelerator when it comes to treatment.
To minimise physical movements of the patient, some sort of immobilisation is typically used. To overcome physiological motion, such as breathing, 4DCT acquires images at a range of times and positions, allowing the extent of motion to be visualised (e.g. from maximum inspiration to maximum exhalation). The treatment plan can then be designed with a knowledge of the full range of possible positions of important organs, and the tumour (target) itself.
4DCT will usually involve a gating technique, such as breathing tracking, so that image acquisition is automatically triggered at set points. This gating can also be applied at treatment, where the radiotherapy beam is only switched o
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https://en.wikipedia.org/wiki/Everything%20is%20a%20file
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Everything is a file is an idea that Unix, and its derivatives, handle input/output to and from resources such as documents, hard-drives, modems, keyboards, printers and even some inter-process and network communications as simple streams of bytes exposed through the filesystem name space. Exceptions include semaphores, processes and threads.
The advantage of this approach is that the same set of tools, utilities and APIs can be used on a wide range of resources and a number of file types. When a file is opened, a file descriptor is created, using the file path as an addressing system. The file descriptor is then a byte stream I/O interface on which file operations are performed. Additionally, file descriptors are also created for objects such as anonymous pipes and network sockets - and therefore a more accurate description of this feature is Everything is a file descriptor.
Additionally, a range of pseudo and virtual filesystems exists which exposes information about processes and other system information in a hierarchical file-like structure. These are mounted into the single file hierarchy.
An example of this purely virtual filesystem is under /proc that exposes many system properties as files. All of these files, in the broader sense of the word, have standard Unix file attributes such as an owner and access permissions, and can be queried by the same classic Unix tools and filters. However, this is not universally considered a fast or portable approach. Some operating systems do not even mount /proc by default due to security or speed concerns. It is, though, used heavily by both the widely installed BusyBox on embedded systems and by procps, which is used on most Linux systems. In both cases it is used in implementations of process-related POSIX shell commands. It is similarly used on Android systems in the operating system's Toolbox program.
See also
Device file
Synthetic file system
Unix architecture
https://www.kernel.org/doc/gorman/html/under
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https://en.wikipedia.org/wiki/Menthofuran
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Menthofuran is an organic compound found in a variety of essential oils including that of pennyroyal (Mentha pulegium). It is highly toxic and believed to be the primary toxin in pennyroyal responsible for its potentially fatal effects. After ingestion of menthofuran, it is metabolically activated to chemically reactive intermediates that are hepatotoxic.
Biosynthesis
Menthofuran is produced biosynthetically from pulegone by the enzyme menthofuran synthase.
Chemistry
Synthesis
Menthofuran can be synthesized from 5-methylcyclohexane-1,3-dione and allenyldimethylsulfonium bromide in two steps via a furannulation strategy consisting of enolate addition and rearrangement.
Pharmacology
Menthofuran is a metabolite of pulegone. Both in vitro and in vivo studies have found the pulegone metabolite menthofuran to be an inhibitor of CYP2A6.
Menthofuran may deplete glutathione levels, leaving hepatocytes vulnerable to free radical damage.
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https://en.wikipedia.org/wiki/F.lux
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f.lux (pronounced "flux") is a cross-platform computer program that adjusts a display's color temperature according to location and time of day, offering functional respite for the eyes. The program is designed to reduce eye strain during night-time use, helping to reduce disruption of sleep patterns.
Functionality
On installation, the user can choose a location based on geographic coordinates, a ZIP code, or the name of a location. The program then automatically calibrates the device display's color temperature to account for time of day, based on sunrise and sunset at the chosen location. At sunset, it will gradually change the color temperature to a warmer color and restore the original color at sunrise.
f.lux offers a variety of color profiles and pre-defined temperature values, modifying program behaviour for specific programs or activities; including a mode for film watching, decreasing red tinge (for 2.5 hours), and a darkroom mode that does not affect night-adapted vision. Times can be inverted on f.lux for PC to provide warm lighting during the daytime (for people who work at night). The program can control Philips Hue LED lighting, so that the color temperature of house lights follows f.lux's settings.
Platforms
The program is available for Microsoft Windows, macOS and Linux (except for Ubuntu 18.04 LTS). It is also available for Apple iOS devices, although it requires the device to be jailbroken. Apple has not allowed the application in its App Store due to its use of restricted developer tools. The developer briefly hosted an Xcode project on GitHub, allowing iOS 9 users to sideload the application onto their devices, but retracted it at the request of Apple. Following Apple's announcement of a similar function, called Night Shift, in iOS 9.3, the developer called upon Apple to provide developer tools and to allow their application into the App Store. A preview version for Google's Android system is available.
Efficacy
Reducing exposure to bright (
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https://en.wikipedia.org/wiki/Punjab%20Breweries%20Workers%20Union
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Punjab Breweries Workers Union, a trade union of brewery workers in Punjab, India. PBWU is affiliated to the All India Trade Union Congress. The president of PBWU is Gurbir Singh and the general secretary Kishan Chand.
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https://en.wikipedia.org/wiki/Bond%20order%20potential
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Bond order potential is a class of empirical (analytical) interatomic potentials which is used in molecular dynamics and molecular statics simulations. Examples include the Tersoff potential, the EDIP potential, the Brenner potential, the Finnis–Sinclair potentials,
ReaxFF,
and the second-moment tight-binding potentials.
They have the advantage over conventional molecular mechanics force fields in that they can, with the same parameters, describe several different bonding states of an atom, and thus to some extent may be able to describe chemical reactions correctly. The potentials were developed partly independently of each other, but share the common idea that the strength of a chemical bond depends on the bonding environment, including the number of bonds and possibly also angles and bond lengths. It is based on the Linus Pauling bond order concept
and can be written in the form
This means that the potential is written as a simple pair potential depending on the distance between two atoms , but the strength of this bond is modified by the environment of the atom via the bond order . is a function that in Tersoff-type potentials depends inversely on the number of bonds to the atom , the bond angles between sets of three atoms , and optionally on the relative bond lengths , . In case of only one atomic bond (like in a diatomic molecule), which corresponds to the strongest and shortest possible bond. The other limiting case, for increasingly many number of bonds within some interaction range, and the potential turns completely repulsive (as illustrated in the figure to the right).
Alternatively, the potential energy can be written in the embedded atom model form
where is the electron density at the location of atom . These two forms for the energy can be shown to be equivalent (in the special case that the bond-order function contains no angular dependence).
A more detailed summary of how the bond order concept can be motivated by the second-moment ap
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https://en.wikipedia.org/wiki/Menudo%20%28stew%29
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Menudo, also known as ginamay or ginagmay (Cebuano: "[chopped into] smaller pieces"), is a traditional stew from the Philippines made with pork and sliced liver in tomato sauce with carrots and potatoes. Unlike the Mexican dish of the same name, it does not use tripe or red chili sauce.
Description
The dish is made with garlic, onions, tomatoes, pork, liver (pork or beef), diced potatoes, raisins, diced carrots, green bell peppers, soy sauce, vinegar or calamansi, and tomato sauce, and seasoned with salt and pepper.
It is one of the most common offerings in carinderias or karinderyas (small eateries that offer budget-friendly meals to local residents) and is also commonly served in potlucks or buffets due to the inexpensive ingredients used in the dish.
Waknatoy
Waknatoy, also called Marikina menudo, is a Filipino pork stew with pickles. It is a variant of the Filipino menudo stew originating from Marikina. It is made with cubed pork and pork liver with sausages (typically Chorizo de Bilbao), red and green bell peppers, tomatoes, garlic, onions, and distinctively, pickle relish, cooked in a tomato-based sauce with salt, pepper, fish sauce, and bay leaves. Waknatoy does not traditionally include other vegetables like potatoes and carrots, like menudo, but they can be included.
See also
Afritada
Igado
Everlasting
Guisantes
List of pork dishes
List of stews
Mechado
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https://en.wikipedia.org/wiki/Viable%20count
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Viable count is a method used in cell culture to determine the number of living cells in a culture. This is different from other cell counting techniques because it makes a distinction between live and dead cells.
Method
A dilution of the cells to be counted is prepared and mixed with Trypan blue, this is normally the stain of choice because it is taken up by dead cells and actively excluded from live cells. Once the cells have been stained they are counted using a Hemocytometer, then a calculation is carried out to determine the original concentration of live cells.
Use in Cell Culture
Determining the viable cell count is important for calculating dilutions required for the passaging of cells, as well as determining the size and number of flasks needed during growth time. It is also vital when seeding plates for assays, such as the plaque assay, because the plates need a known number of live replicating cells for the virus to attach to and replicate in, in order to get an accurate result.
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https://en.wikipedia.org/wiki/Molality
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In chemistry, molality is a measure of the amount of solute in a solution relative to a given mass of solvent. This contrasts with the definition of molarity which is based on a given volume of solution.
A commonly used unit for molality is the moles per kilogram (mol/kg). A solution of concentration 1 mol/kg is also sometimes denoted as 1 molal. The unit mol/kg requires that molar mass be expressed in kg/mol, instead of the usual g/mol or kg/kmol.
Definition
The molality (b), of a solution is defined as the amount of substance (in moles) of solute, nsolute, divided by the mass (in kg) of the solvent, msolvent:
In the case of solutions with more than one solvent, molality can be defined for the mixed solvent considered as a pure pseudo-solvent. Instead of mole solute per kilogram solvent as in the binary case, units are defined as mole solute per kilogram mixed solvent.
Origin
The term molality is formed in analogy to molarity which is the molar concentration of a solution. The earliest known use of the intensive property molality and of its adjectival unit, the now-deprecated molal, appears to have been published by G. N. Lewis and M. Randall in the 1923 publication of Thermodynamics and the Free Energies of Chemical Substances. Though the two terms are subject to being confused with one another, the molality and molarity of a dilute aqueous solution are nearly the same, as one kilogram of water (solvent) occupies the volume of 1 liter at room temperature and a small amount of solute has little effect on the volume.
Unit
The SI unit for molality is moles per kilogram of solvent.
A solution with a molality of 3 mol/kg is often described as "3 molal", "3 m" or "3 m". However, following the SI system of units, the National Institute of Standards and Technology, the United States authority on measurement, considers the term "molal" and the unit symbol "m" to be obsolete, and suggests mol/kg or a related unit of the SI.
Usage considerations
Advantages
The pri
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https://en.wikipedia.org/wiki/Colin%20McLarty
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Colin McLarty (born July 12, 1951) is an American logician whose publications have ranged widely in philosophy and the foundations of mathematics, as well as in the history of science and of mathematics.
Research
Category theory
He has written papers about Saunders Mac Lane, one of the founders of category theory.
McLarty's Elementary Categories and Elementary Toposes describes category theory and topos theory at an elementary level.
McLarty worked on establishing that Fermat's Last Theorem can be proven in a setting with much weaker assumptions than the ones used in Wiles' proof, which makes use of involved category theoretical constructions.
History of Mathematics
He is a member of the Grothendieck Circle, which provides on-line and open access to many writings about the mathematician Alexandre Grothendieck, who revolutionized Banach-space theory and algebraic geometry and whose life has fascinated many biographers and mathematical scientists.
McLarty has also written about the German algebraist Emmy Noether and her involvement with German political history.
Positions
At Case Western Reserve University (CWRU), Colin McLarty is the Truman P. Handy Professor of Philosophy and the current Chair of the Philosophy Department.
At CWRU, he is also a professor of mathematics.
Bibliography
Colin McLarty, The Uses and Abuses of the History of Topos Theory, Br. J. Philos. Sci, 41 (1990) p 355.
Colin McLarty, 'Emmy Noether’s ‘Set Theoretic’ Topology: From Dedekind to the rise of functors' in The Architecture of Modern Mathematics: Essays in history and philosophy (edited by Jeremy Gray and José Ferreirós), Oxford University Press (2006) p. 187–208.
McLarty, Colin, 2005, "Saunders Mac Lane (1909–2005): His Mathematical Life and Philosophical Works," Philosophia Mathematica 13: 237–51. With selected bibliography emphasizing Mac Lane's philosophical writings.
--------, 2007, "The Last Mathematician from Hilbert's Göttingen: Saunders Mac Lane as Philosopher of M
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https://en.wikipedia.org/wiki/NEC%20SX
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NEC SX describes a series of vector supercomputers designed, manufactured, and marketed by NEC. This computer series is notable for providing the first computer to exceed 1 gigaflop, as well as the fastest supercomputer in the world between 1992–1993, and 2002–2004. The current model, as of 2018, is the SX-Aurora TSUBASA.
History
The first models, the SX-1 and SX-2, were announced in April 1983, and released in 1985. The SX-2 was the first computer to exceed 1 gigaflop. The SX-1 and SX-1E were less powerful models offered by NEC.
The SX-3 was announced in 1989, and shipped in 1990. The SX-3 allows parallel computing using both SIMD and MIMD. It also switched from the ACOS-4 based SX-OS, to the AT&T System V UNIX-based SUPER-UX operating system. In 1992 an improved variant, the SX-3R, was announced. A SX-3/44 variant was the fastest computer in the world between 1992-1993 on the TOP500 list. It had LSI integrated circuits with 20,000 gates per IC with a per-gate delay time of 70 picoseconds, could house 4 arithmetic processors with up to 4 sharing the same main memory, and up to several processors to achieve up to 22 GFLOPS of performance, with 1.37 GFLOPS of performance with a single processor. 100 LSI ICs were housed in a single multi chip module to achieve 2 million gates per module. The modules were watercooled.
The SX-4 series was announced in 1994, and first shipped in 1995. Since the SX-4, SX series supercomputers are constructed in a doubly parallel manner. A number of central processing units (CPUs) are arranged into a parallel vector processing node. These nodes are then installed in a regular SMP arrangement.
The SX-5 was announced and shipped in 1998, with the SX-6 following in 2001, and the SX-7 in 2002. Starting in 2001, Cray marketed the SX-5 and SX-6 exclusively in the US, and non-exclusively elsewhere for a short time.
The Earth Simulator, built from SX-6 nodes, was the fastest supercomputer from June 2002 to June 2004 on the LINPACK benchmark
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https://en.wikipedia.org/wiki/Gopher%20wood
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Gopher wood or gopherwood is a term used once in the Bible for the material used to construct Noah's ark. states that Noah was instructed to build the Ark of (), commonly transliterated as wood, a word not otherwise used in the Bible or the Hebrew language in general. Although some English Bibles attempt a translation, older English translations such as the King James Version (17th century) leave it untranslated. The word is unrelated to the North American animal known as the gopher.
Identity
The Greek Septuagint (3rd–1st centuries BC) translated the phrase mentioning gopher wood as (), 'out of squared timber', translating gofer as squared. Similarly, the Latin Vulgate (5th century AD) rendered it as (, in the spelling of the Clementine Vulgate), 'of timber planks'.
The Jewish Encyclopedia states that it was most likely a translation of the Babylonian , 'cedar beams', or the Assyrian , 'reeds'. The Aramaic Targum Onkelos, considered by many Jews to be an authoritative translation of the Hebrew scripture, renders this word as , 'cedar'. The Syriac Peshitta translates this word as , 'box'.
Many modern English translations favor cypress (otherwise referred to in Biblical Hebrew as ). This was espoused (among others) by Adam Clarke, a Methodist theologian famous for his commentary on the Bible: Clarke cited a resemblance between the Greek word for cypress, , and the Hebrew word . Likewise, the (20th century) has it as ('out of cypress wood').
Others, noting the visual similarity between the Hebrew letters g (gimel ) and k (kaf ), suggest that the word may actually be , the Hebrew word meaning 'pitch'; thus wood would be 'pitched wood'. Recent suggestions have included a lamination process (to strengthen the Ark), or a now-lost type of tree, but there is no consensus.
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https://en.wikipedia.org/wiki/Biochemical%20systems%20theory
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Biochemical systems theory is a mathematical modelling framework for biochemical systems, based on ordinary differential equations (ODE), in which biochemical processes are represented using power-law expansions in the variables of the system.
This framework, which became known as Biochemical Systems Theory, has been developed since the 1960s by Michael Savageau, Eberhard Voit and others for the systems analysis of biochemical processes. According to Cornish-Bowden (2007) they "regarded this as a general theory of metabolic control, which includes both metabolic control analysis and flux-oriented theory as special cases".
Representation
The dynamics of a species is represented by a differential equation with the structure:
where Xi represents one of the nd variables of the model (metabolite concentrations, protein concentrations or levels of gene expression). j represents the nf biochemical processes affecting the dynamics of the species. On the other hand, ij (stoichiometric coefficient), j (rate constants) and fjk (kinetic orders) are two different kinds of parameters defining the dynamics of the system.
The principal difference of power-law models with respect to other ODE models used in biochemical systems is that the kinetic orders can be non-integer numbers. A kinetic order can have even negative value when inhibition is modeled. In this way, power-law models have a higher flexibility to reproduce the non-linearity of biochemical systems.
Models using power-law expansions have been used during the last 35 years to model and analyze several kinds of biochemical systems including metabolic networks, genetic networks and recently in cell signalling.
See also
Dynamical systems
Ludwig von Bertalanffy
Systems theory
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https://en.wikipedia.org/wiki/Geranium%20%C3%97%20cantabrigiense
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Geranium × cantabrigiense is a hybrid flowering plant in the cranesbill family Geraniaceae. It is an hybrid between Geranium dalmaticum and G. macrorrhizum.
Etymology
The name cantabrigiense comes from Cantabrigia, the Latin name for Cambridge, England.
Origin
Geranium × cantabrigiense was originally obtained in cultivation in 1974, when Dr. Helen Kiefer of the Cambridge University Botanic Garden used pollen of G. dalmaticum to fertilise G. macrorrhizum. The resulting plant is sterile, producing long-lasting pink flowers that do not set seed, but spreads vegetatively through trailing stems.
This hybrid has since been found in the wild, having formed through natural hybridisation where both parents co-occur. One naturally occurring form discovered in the Biokovo mountains of Croatia has been introduced in cultivation as the cultivar 'Biokovo'.
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https://en.wikipedia.org/wiki/Convex%20geometry
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In mathematics, convex geometry is the branch of geometry studying convex sets, mainly in Euclidean space. Convex sets occur naturally in many areas: computational geometry, convex analysis, discrete geometry, functional analysis, geometry of numbers, integral geometry, linear programming, probability theory, game theory, etc.
Classification
According to the Mathematics Subject Classification MSC2010, the mathematical discipline Convex and Discrete Geometry includes three major branches:
general convexity
polytopes and polyhedra
discrete geometry
(though only portions of the latter two are included in convex geometry).
General convexity is further subdivided as follows:
axiomatic and generalized convexity
convex sets without dimension restrictions
convex sets in topological vector spaces
convex sets in 2 dimensions (including convex curves)
convex sets in 3 dimensions (including convex surfaces)
convex sets in n dimensions (including convex hypersurfaces)
finite-dimensional Banach spaces
random convex sets and integral geometry
asymptotic theory of convex bodies
approximation by convex sets
variants of convex sets (star-shaped, (m, n)-convex, etc.)
Helly-type theorems and geometric transversal theory
other problems of combinatorial convexity
length, area, volume
mixed volumes and related topics
valuations on convex bodies
inequalities and extremum problems
convex functions and convex programs
spherical and hyperbolic convexity
Historical note
Convex geometry is a relatively young mathematical discipline. Although the first known contributions to convex geometry date back to antiquity and can be traced in the works of Euclid and Archimedes, it became an independent branch of mathematics at the turn of the 20th century, mainly due to the works of Hermann Brunn and Hermann Minkowski in dimensions two and three. A big part of their results was soon generalized to spaces of higher dimensions, and in 1934
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https://en.wikipedia.org/wiki/Ofer%20Zeitouni
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Ofer Zeitouni (עפר זיתוני, born 23 October 1960, Haifa) is an Israeli mathematician, specializing in probability theory.
Biography
Zeitouni received his bachelor's degree in electrical engineering in 1980 from the Technion.
He obtained in 1986 his doctorate in electrical engineering under the supervision of
Moshe Zakai with the thesis Bounds on the Conditional Density and Maximum a posteriori Estimators for the Nonlinear Filtering Problem. As a postdoc he was a visiting assistant professor at Brown University and at the Laboratory for Information and Decision Systems at MIT. He joined the Technion in 1989 as senior lecturer, and was promoted in 1991 to associate professor, and in 1997 to full professor in the department of electrical engineering. He is now a professor of Mathematics at the Weizmann Institute and at the Courant Institute, and was from 2002 to 2013 a part-time professor at the University of Minnesota.
His research deals with stochastic processes and filtering theory with applications to control theory (electrical engineering), the spectral theory of random matrices, the theory of large deviations in probability theory, motion in random media,
and extremes of logarithmically correlated fields.
He was Invited Speaker with the talk Random Walks in Random Environments at the ICM in Beijing in 2002. Zeitouni is a Fellow of the American Mathematical Society, member
of the American Academy of Arts and Sciences, the
National Academy of Sciences, and the Israel Academy of Sciences and Humanities.
He is married and has two children.
Selected publications
Articles
with Ildar Abdulovich Ibragimov:
with Amir Dembo, Yuval Peres, and Jay Rosen:
with Amir Dembo, Bjorn Poonen, and Qi-Man Shao:
with Amir Dembo, Yuval Peres, and Jay Rosen:
Books
with Greg W. Anderson and Alice Guionnet: Introduction to Random Matrices, Cambridge University Press 2010
with Amir Dembo: Large Deviations Techniques and Applications, Springer 1998,
Sources
Zhan Shi: Problème
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https://en.wikipedia.org/wiki/Robert%20Koch%20Medal%20and%20Award
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The Robert Koch Medal and Award are two prizes awarded annually by the German for excellence in the biomedical sciences. These awards grew out of early attempts by German physician Robert Koch to generate funding to support his research into the cause and cure for tuberculosis. Koch discovered the bacteria (Mycobacterium tuberculosis) responsible for the dreaded disease and rapidly acquired international support, including 500,000 gold marks from the Scottish-American philanthropist Andrew Carnegie.
The Robert Koch Prize
Since 1970, the Robert Koch Foundation has awarded prizes for major advances in the biomedical sciences, particularly in the fields of microbiology and immunology. The prestige of this award has grown over the past decades so that it is now widely regarded as the leading international scientific prize in microbiology. As has been described by a jury member for the prize, the committee often asks, "What would Robert Koch work on today?” to decide on research that should be granted recognition.
The more specific Robert Koch Prize is commonly considered one of the stepping-stones (along with other prizes such as the Lasker Award) to eventual Nobel Prize recognition for scientists in the fields of microbiology and immunology, and a number of Robert Koch Prize winners subsequently became Nobel laureates, such as César Milstein, Susumu Tonegawa and Harald zur Hausen. Other notable awardees include Albert Sabin, Jonas Salk and John Enders for their pioneering work on the development of polio vaccines. Only Enders was recognized with a Nobel Prize, together with Thomas Huckle Weller and Frederick Chapman Robbins.
Two separate Robert Koch Awards are presented annually: The Gold Robert Koch Gold Medal for accumulated excellence in biomedical research and the Robert Koch Prize, worth €120,000, for a major discovery in biomedical science.
Robert Koch Prize Winners since 1960
Source:
1960 (Germany), René Dubos (USA), (Japan), (Germany), (German
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https://en.wikipedia.org/wiki/Inverse-square%20law
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In science, an inverse-square law is any scientific law stating that a specified physical quantity is inversely proportional to the square of the distance from the source of that physical quantity. The fundamental cause for this can be understood as geometric dilution corresponding to point-source radiation into three-dimensional space.
Radar energy expands during both the signal transmission and the reflected return, so the inverse square for both paths means that the radar will receive energy according to the inverse fourth power of the range.
To prevent dilution of energy while propagating a signal, certain methods can be used such as a waveguide, which acts like a canal does for water, or how a gun barrel restricts hot gas expansion to one dimension in order to prevent loss of energy transfer to a bullet.
Formula
In mathematical notation the inverse square law can be expressed as an intensity (I) varying as a function of distance (d) from some centre. The intensity is proportional (see ∝) to the reciprocal of the square of the distance thus:
It can also be mathematically expressed as:
or as the formulation of a constant quantity:
The divergence of a vector field which is the resultant of radial inverse-square law fields with respect to one or more sources is proportional to the strength of the local sources, and hence zero outside sources. Newton's law of universal gravitation follows an inverse-square law, as do the effects of electric, light, sound, and radiation phenomena.
Justification
The inverse-square law generally applies when some force, energy, or other conserved quantity is evenly radiated outward from a point source in three-dimensional space. Since the surface area of a sphere (which is 4πr2) is proportional to the square of the radius, as the emitted radiation gets farther from the source, it is spread out over an area that is increasing in proportion to the square of the distance from the source. Hence, the intensity of radiation pas
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https://en.wikipedia.org/wiki/Sofosbuvir
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Sofosbuvir, sold under the brand name Sovaldi among others, is a medication used to treat hepatitis C. It is taken by mouth.
Common side effects include fatigue, headache, nausea, and trouble sleeping. Side effects are generally more common in interferon-containing regimens. Sofosbuvir may reactivate hepatitis B in those who have been previously infected. In combination with ledipasvir, daclatasvir or simeprevir, it is not recommended with amiodarone due to the risk of an abnormally slow heartbeat. Sofosbuvir is in the nucleotide analog family of medications and works by blocking the hepatitis C NS5B protein.
Sofosbuvir was discovered in 2007 and approved for medical use in the United States in 2013. It is on the World Health Organization's List of Essential Medicines.
Medical uses
Initial HCV treatment
In 2016, the American Association for the Study of Liver Diseases and the Infectious Diseases Society of America jointly published a recommendation for the management of hepatitis C. In this recommendation, sofosbuvir used in combination with other drugs is part of all first-line treatments for HCV genotypes 1, 2, 3, 4, 5, and 6, and is also part of some second-line treatments. Sofosbuvir in combination with velpatasvir is recommended for all genotypes with a cure rate greater than 90%, and close to 100% in most cases. The duration of treatment is typically 12 weeks.
Sofosbuvir is also used with other medications and longer treatment durations, depending on specific circumstances, genotype and cost-effectiveness–based perspective. For example, for the treatment of genotypes 1, 4, 5, and 6 hepatitis C infections, sofosbuvir can be used in combination with the viral NS5A inhibitor ledipasvir. In genotype 2 and 3 HCV infections, sofosbuvir can be used in combination with daclatasvir. For the treatment of cases with cirrhosis or liver transplant patients, weight-based ribavirin is sometimes added. Peginterferon with or without sofosbuvir is not recommended in an in
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https://en.wikipedia.org/wiki/Synthetic%20geometry
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Synthetic geometry (sometimes referred to as axiomatic geometry or even pure geometry) is geometry without the use of coordinates. It relies on the axiomatic method for proving all results from a few basic properties initially called postulate, and at present called axioms.
The term "synthetic geometry" was coined only after the 17th century, and the introduction by René Descartes of the coordinate method, which was called analytic geometry. So the term "synthetic geometry" was introduced to refer to the older methods that were, before Descartes, the only known ones.
According to Felix Klein
Synthetic geometry is that which studies figures as such, without recourse to formulae, whereas analytic geometry consistently makes use of such formulae as can be written down after the adoption of an appropriate system of coordinates.
The first systematic approach for synthetic geometry is Euclid's Elements. However, it appeared at the end of the 19th century that Euclid's postulates were not sufficient for characterizing geometry. The first complete axiom system for geometry was given only at the end of the 19th century by David Hilbert. At the same time, it appeared that both synthetic methods and analytic methods can be used to build geometry. The fact that the two approches are equivalent has been proved by Emil Artin in his book Geometric Algebra.
Because of this equivalence, the distinction between synthetic and analytic geometry is no more in use, except at elementary level, or for geometries that are not related to any sort of numbers, such as some finite geometries and non-Desarguesian geometry.
Logical synthesis
The process of logical synthesis begins with some arbitrary but definite starting point. This starting point is the introduction of primitive notions or primitives and axioms about these primitives:
Primitives are the most basic ideas. Typically they include both objects and relationships. In geometry, the objects are things such as points, lines and
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https://en.wikipedia.org/wiki/Diamond%20norm
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In quantum information, the diamond norm, also known as completely bounded trace norm, is a norm on the space of quantum operations, or more generally on any linear map that acts on complex matrices. Its main application is to measure the "single use distinguishability" of two quantum channels. If an agent is randomly given one of two quantum channels, permitted to pass one state through the unknown channel, and then measures the state in an attempt to determine which operation they were given, then their maximal probability of success is determined by the diamond norm of the difference of the two channels.
Although the diamond norm can be efficiently computed via semidefinite programming, it is in general difficult to obtain analytical expressions and those are known only for a few particular cases.
Definition
The diamond norm is the trace norm of the output of a trivial extension of a linear map, maximized over all possible inputs with trace norm at most one. More precisely, let be a linear transformation, where denotes the complex matrices, let be the identity map on matrices, and . Then the diamond norm of is given by
where denotes the trace norm.
The diamond norm induces the diamond distance, which in the particular case of completely positive, trace non-increasing maps is given by
where the maximization is done over all density matrices of dimension .
Discrimination of quantum channels
In the task of single-shot discrimination of quantum channels, an agent is given one of the channels with probabilities p and 1-p, respectively, and attempts to guess which channel they received by preparing a state , passing it through the unknown channel, and making a measurement on the resulting state. The maximal probability that the agent guesses correctly is given by
Semidefinite programming formulation
The diamond norm can be efficiently calculated via semidefinite programming. Let be a linear map, as before, and its Choi state, defined as
.
Th
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https://en.wikipedia.org/wiki/Soil%20biodiversity
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Soil biodiversity refers to the relationship of soil to biodiversity and to aspects of the soil that can be managed in relative to biodiversity. Soil biodiversity relates to some catchment management considerations.
Biodiversity
According to the Australian Department of the Environment and Water Resources, biodiversity is "the variety of life: the different plants, animals and micro-organisms, their genes and the ecosystems of which they are a part." Biodiversity and soil are strongly linked, because soil is the medium for a large variety of organisms, and interacts closely with the wider biosphere. Conversely, biological activity is a primary factor in the physical and chemical formation of soils.
Soil provides a vital habitat, primarily for microbes (including bacteria and fungi), but also for microfauna (such as protozoa and nematodes), mesofauna (such as microarthropods and enchytraeids), and macrofauna (such as earthworms, termites, and millipedes). The primary role of soil biota is to recycle organic matter that is derived from the "above-ground plant-based food web".
Soil is in close cooperation with the wider biosphere. The maintenance of fertile soil is "one of the most vital ecological services the living world performs", and the "mineral and organic contents of soil must be replenished constantly as plants consume soil elements and pass them up the food chain".
The correlation of soil and biodiversity can be observed spatially. For example, both natural and agricultural vegetation boundaries correspond closely to soil boundaries, even at continental and global scales.
A "subtle synchrony" is how Baskin (1997) describes the relationship that exists between the soil and the diversity of life, above and below the ground. It is not surprising that soil management has a direct effect on biodiversity. This includes practices that influence soil volume, structure, biological, and chemical characteristics, and whether soil exhibits adverse effects such as re
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https://en.wikipedia.org/wiki/Marsden%20square
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Marsden square mapping or Marsden squares is a system that divides a world map with latitude-longitude gridlines (e.g. plate carrée projection, Mercator or other) between 80°N and 70°S latitudes (or 90°N and 80°S: refer chart at Ocean Teacher’s Ocean Geography page) into grid cells of 10° latitude by 10° longitude, each with a geocode, a unique numeric identifier. The method was devised by William Marsden (b. 1754, d. 1836), when first secretary of the British Admiralty, for collecting and combining geographically based information about the oceans.
Structure and design
On the plate carrée projection the grid cells appear square, although if the Mercator projection is used, the grid cells appear "stretched" vertically nearer the tops and bottoms of the map. On the actual surface of the globe, the cells are approximately "square" only adjacent to the equator, and become progressively narrower and tapered (also with curved northern and southern boundaries) as they approach the poles, and cells adjoining the poles are unique in possessing three faces rather than four. Each of the 540 10°x10° squares is allocated a unique number from 1 to 288 and from 300 to 551 (see image to the right), plus the sequence extends to 936 in higher latitudes; individual squares can also be subdivided into 100 one-degree squares numbered from 00 to 99 in order to improve precision.
Use
Marsden squares have mostly been used for identifying the geographic position of meteorological data, and are described further in various publications of the World Meteorological Organization (WMO). The 10°x10° square identifiers typically use a minimal number of characters (between 1 and 3 digits) which was/is an operational advantage for low bandwidth transmission systems.
However the rules for allocating numbers to squares do not follow a consistent pattern, so that reverse-engineering (decoding) the relevant square boundaries from any particular Marsden Square identifier is not particularly straig
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https://en.wikipedia.org/wiki/Animal%20trypanosomiasis
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Animal trypanosomiasis, also known as nagana and nagana pest, or sleeping sickness, is a disease of vertebrates. The disease is caused by trypanosomes of several species in the genus Trypanosoma such as T. brucei. T. vivax causes nagana mainly in West Africa, although it has spread to South America. The trypanosomes infect the blood of the vertebrate host, causing fever, weakness, and lethargy, which lead to weight loss and anemia; in some animals the disease is fatal unless treated. The trypanosomes are transmitted by tsetse flies.
An interesting feature is the remarkable tolerance to nagana pathology shown by some breeds of cattle, notably the N'Dama – a West African Bos taurus breed. This contrasts with the susceptibility shown by East African B. indicus cattle such as the zebu.
Transmission
Most trypanosomes develop in tsetse flies (Glossina spp.), its biological vector, in about one to a few weeks. When an infected tsetse fly bites an animal, the parasites are transmitted through its saliva. It can also be spread by fomites such as surgical instruments, needles, and syringes. The most important vectors are thought to be horseflies (Tabanidae spp.) and stable flies (Stomoxys spp.).
The immune response of animals may be unable to eliminate trypanosomes completely, and the host may become an inapparent carrier. These inapparent infections can be reactivated if the animal is stressed. Transplacental transmission can also occur.
Transmission was successfully halted on Zanzibar by sterile insect technique (SIT) of the vector Glossina austeni.
Signs and symptoms
The incubation period ranges from four days to approximately eight weeks. The infection leads to significant weight loss and anemia. Various symptoms are observed, including fever, oedema, adenitis, dermatitis and nervous disorders. The disease cannot be diagnosed with certainty except physically detecting parasites by blood microscopic examination or various serological reactions.
Vectors
Control meas
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https://en.wikipedia.org/wiki/UNIVAC%201100/2200%20series
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The UNIVAC 1100/2200 series is a series of compatible 36-bit computer systems, beginning with the UNIVAC 1107 in 1962, initially made by Sperry Rand. The series continues to be supported today by Unisys Corporation as the ClearPath Dorado Series. The solid-state 1107 model number was in the same sequence as the earlier vacuum-tube computers, but the early computers were not compatible with the solid-state successors.
Architecture
Data formats
Fixed-point, either integer or fraction
Whole word – 36-bit (ones' complement)
Half word – two 18-bit fields per word (unsigned or ones' complement)
Third word – three 12-bit fields per word (ones' complement)
Quarter word – four 9-bit fields per word (unsigned)
Sixth word – six 6-bit fields per word (unsigned)
Floating point
Single precision – 36 bits: sign bit, 8-bit characteristic, 27-bit mantissa
Double precision – 72 bits: sign bit, 11-bit characteristic, 60-bit mantissa
Alphanumeric
FIELDATA – UNIVAC 6-bit code variant (no lower case characters) six characters in each 36-bit word. (FIELDATA was originally a seven-bit code of which only 64 code positions (occupying six bits) were formally defined.)
ASCII – 9 bits per character (right-most eight used for an ASCII character) four characters in each 36-bit word
Instruction format
Instructions are 36 bits long with the following fields:
f (6 bits) - function designator (opcode),
j (4 bits) - partial word designator, J-register designator, or minor function designator,
a (4 bits) - register (A, X, or R) designator or I/O designator,
x (4 bits) - index register (X) designator,
h (1 bit ) - index register increment designator,
i (1 bit) - indirect address designator,
u (16 bits) - address or operand designator.
Registers
The 128 registers of the high-speed "general register stack" ("integrated circuit registers" on the UNIVAC 1108 and UNIVAC 1106 models), map to the current data space in main storage starting at memory address zero. These registers include both user and exec
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https://en.wikipedia.org/wiki/One%20UI
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One UI is a user interface (UI) developed by Samsung Electronics for its Android devices running Android 9 "Pie" and later. Succeeding Samsung Experience and TouchWiz, it is designed to make using larger smartphones easier and be more visually appealing. To provide more clarity, some elements of the UI are tweaked to match colors that are based on the color of the user's phone. It was announced at Samsung Developer Conference in 2018, and was unveiled in Galaxy Unpacked in February 2019 alongside the Galaxy S10 series, Galaxy Buds and the Galaxy Fold.
It is also the software layer for their smartwatch Tizen and Wear OS platform, which Samsung co-developed with Google. As of 2021, it is also the software layer for the Microsoft Windows platform on Galaxy Book devices.
Features
One UI was designed as part of a goal to make Samsung's hardware and software "work together in perfect harmony" and provide a more "natural" experience on large-screen smartphones. One UI displays most of the features that were in the Samsung Experience UX. A prominent design pattern in many of Samsung's system applications is to intentionally place common features and user interface elements along the middle of the screen rather than near the top. This makes them easier to reach with a user's thumb when using the device one-handed.
For similar reasons, apps utilise large headers to push their main content towards the vertical centre of the screen. The navigation bar supports the use of gestures and the usual 3-button system, while a system-wide "night mode" was also added (which gives UI elements and supported applications a darkened color scheme). As with Android Pie upstream, the Overview screen of recent apps uses a horizontal layout, as opposed to the vertical layout of previous versions.
One UI Core
One UI Core is a slimmed down version of the original One UI feature set aimed towards the budget-friendly A, F, and M series low and mid-range devices. These variants of the system usu
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https://en.wikipedia.org/wiki/Index%20of%20physics%20articles%20%28H%29
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The index of physics articles is split into multiple pages due to its size.
To navigate by individual letter use the table of contents below.
H
H-1NF
H-alpha
H-stable potential
H-theorem
H. Dieter Zeh
H. Eugene Stanley
H. J. Round
H. Jay Melosh
H. Pierre Noyes
H. Richard Crane
H. Stanley Allen
H1 (particle detector)
HEPnet
HERA-B
HERMES experiment
HITRAP
HLX-1
HT-7
High-temperature engineering test reactor
Haag's theorem
Haag–Lopuszanski–Sohnius theorem
Hadamard–Rybczynski equation
Hadron
Hadron Elektron Ring Anlage
Hadron epoch
Hadron spectroscopy
Hadronization
Hafele–Keating experiment
Hafnium controversy
Hagedorn temperature
Hagen Kleinert
Hagen–Poiseuille equation
Hagen–Poiseuille flow from the Navier–Stokes equations
Haidinger fringe
Haim Harari
Hajo Meyer
Hal Anger
Halbach array
Halden Boiling Water Reactor
Halden Reactor
Half-life
Half-metal
Half-value layer
Half time (physics)
Hall effect
Hall effect sensor
Hall effect thruster
Hall probe
Halo (optical phenomenon)
Halo Occupation Distribution
Halo nucleus
Halothermal circulation
Halpin–Tsai model
Halton Arp
Hamilton's principal function
Hamilton's principle
Hamiltonian (quantum mechanics)
Hamiltonian constraint
Hamiltonian fluid mechanics
Hamiltonian lattice gauge theory
Hamiltonian mechanics
Hamiltonian system
Hamiltonian vector field
Hamilton–Jacobi equation
Hammar experiment
Hampson–Linde cycle
Hanany–Witten transition
Hanbury Brown and Twiss effect
Hand boiler
Handbook of Porphyrin Science
Hang gliding
Hanna Nasser (academic)
Hannay angle
Hannes Alfvén
Hannes Alfvén Prize
Hanns Hörbiger
Hannspeter Winter
Hans-Arwed Weidenmüller
Hans-Dieter Betz
Hans-Hermann Hupfeld
Hans-Joachim Queisser
Hans-Peter Dürr
Hans Albert Einstein
Hans Benndorf
Hans Bethe
Hans Breuer (physicist)
Hans Christian von Baeyer
Hans Christian Ørsted
Hans Eduard Suess
Hans Ferdinand Mayer
Hans Frauenfelder
Hans G. Hornung
Hans Geiger
Hans Georg Dehmelt
Hans Grassmann
Hans Hellmann
Hans Henrik Andersen
Hans Hollmann
Hans K. Ziegler
Ha
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https://en.wikipedia.org/wiki/Ground%20conductivity
|
Ground conductivity refers to the electrical conductivity of the subsurface of the earth. In the International System of Units (SI) it is measured in millisiemens per meter (mS/m).
Radio propagation
Ground conductivity is an extremely important factor in determining the field strength and propagation of surface wave (ground wave) radio transmissions. Low frequency (30–300 kHz) and medium frequency (300–3000 kHz) radio transmissions are particularly reliant on good ground conductivity as their primary propagation is by surface wave. It also affects the real world radiation pattern of high frequency (3-30 MHz) antennas, as the so called "takeoff angle" is not an inherent property of the antenna but a result of a ground reflection. For this reason ITU publishes an extensive world atlas of ground conductivities.
Other uses
Ground conductivity is sometimes used in determining the efficiency of a septic tank, using electromagnetic induction, so that contaminants do not reach the surface or nearby water supplies.
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https://en.wikipedia.org/wiki/Clifford%20Cocks
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Clifford Christopher Cocks (born 28 December 1950) is a British mathematician and cryptographer.
In 1973, while working at the United Kingdom Government Communications Headquarters (GCHQ), he invented a public-key cryptography algorithm equivalent to what would become (in 1977) the RSA algorithm.
The idea was classified information and his insight remained hidden for 24 years, although it was independently invented by Ronald Rivest, Adi Shamir, and Leonard Adleman in 1977. Public-key cryptography using prime factorisation is now part of nearly every Internet transaction.
Education
Cocks was educated at Manchester Grammar School and went on to study the Mathematical Tripos as an undergraduate at King's College, Cambridge. He continued as a PhD student at the University of Oxford, where he specialised in number theory under Bryan Birch, but left academia without finishing his doctorate.
Career
Non-secret encryption
Cocks left Oxford to join Communications-Electronics Security Group (CESG), an arm of GCHQ, in September 1973. Soon after, Nick Patterson told Cocks about James H. Ellis' non-secret encryption, an idea which had been published in 1969 but never successfully implemented. Several people had attempted creating the required one-way functions, but Cocks, with his background in number theory, decided to use prime factorization, and did not even write it down at the time. With this insight, he quickly developed what later became known as the RSA encryption algorithm.
GCHQ was not able to find a way to use the algorithm, and treated it as classified information. The scheme was also passed to the NSA. With a military focus, financial considerations, and low computing power, the power of public-key cryptography was unrealised in both organisations:
I judged it most important for military use. In a fluid military situation you may meet unforeseen threats or opportunities.
... if you can share your key rapidly and electronically, you have a major advantage over
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https://en.wikipedia.org/wiki/Chromatin%20immunoprecipitation
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Chromatin immunoprecipitation (ChIP) is a type of immunoprecipitation experimental technique used to investigate the interaction between proteins and DNA in the cell. It aims to determine whether specific proteins are associated with specific genomic regions, such as transcription factors on promoters or other DNA binding sites, and possibly define cistromes. ChIP also aims to determine the specific location in the genome that various histone modifications are associated with, indicating the target of the histone modifiers. ChIP is crucial for the advancements in the field of epigenomics and learning more about epigenetic phenomena.
Briefly, the conventional method is as follows:
DNA and associated proteins on chromatin in living cells or tissues are crosslinked (this step is omitted in Native ChIP).
The DNA-protein complexes (chromatin-protein) are then sheared into ~500 bp DNA fragments by sonication or nuclease digestion.
Cross-linked DNA fragments associated with the protein(s) of interest are selectively immunoprecipitated from the cell debris using an appropriate protein-specific antibody.
The associated DNA fragments are purified and their sequence is determined. Enrichment of specific DNA sequences represents regions on the genome that the protein of interest is associated with in vivo.
Typical ChIP
There are mainly two types of ChIP, primarily differing in the starting chromatin preparation. The first uses reversibly cross-linked chromatin sheared by sonication called cross-linked ChIP (XChIP). Native ChIP (NChIP) uses native chromatin sheared by micrococcal nuclease digestion.
Cross-linked ChIP (XChIP)
Cross-linked ChIP is mainly suited for mapping the DNA target of transcription factors or other chromatin-associated proteins, and uses reversibly cross-linked chromatin as starting material. The agent for reversible cross-linking could be formaldehyde or UV light. Then the cross-linked chromatin is usually sheared by sonication, providing fragments
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https://en.wikipedia.org/wiki/Mr.%20Peanut
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Mr. Peanut is the advertising logo and mascot of Planters, an American snack-food company owned by Hormel. He is known for dying in January of 2020, but revived a couple days later. He is depicted as an anthropomorphic peanut in its shell, wearing the formal clothing of an old-fashioned gentleman, with a top hat, monocle, white gloves, spats, and cane. He is reported of British heritage and has the proper name of Bartholomew Richard Fitzgerald-Smythe.
History
Planters Peanut Company was founded in 1906 in Wilkes-Barre, Pennsylvania by Amedeo Obici, and incorporated two years later as the Planters Nut and Chocolate Company. In 1916, a young schoolboy, Antonio Gentile submitted drawings of an anthropomorphic peanut to a design contest. When his design was chosen, commercial artist Andrew S. Wallach added the monocle, top hat, and cane to create the iconic image. Gentile's family originally received five dollars for winning the contest. Obici befriended them and paid Antonio’s, and four of his siblings', way through college. After Obici paid Antonio's way through medical school as well, Antonio became a doctor in Newport News, where he died of a heart attack in 1939.
There is a disputed claim that Frank P. Krize Sr., a Wilkes-Barre artist and head of the Suffolk plant, made the additions of the monocle, top hat, and cane. Wallach's daughter, Virginia, maintains that Krize joined the project after Mr. Peanut was created. However, neither Planters' history nor other sources still in circulation positively identify the artist.
By the mid-1930s, the raffish figure had come to symbolize the entire peanut industry. Mr. Peanut has appeared on almost every Planters package and advertisement and is one of the best-known icons in advertising history.
He has appeared in many TV commercials as an animated cartoon character. More recent commercials have shown him stop-motion animated in a real-world setting.
In 2005, Mr. Peanut was shown in MasterCard's "Icons" commercial dur
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https://en.wikipedia.org/wiki/777%20%28number%29
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777 (seven hundred [and] seventy-seven) is the natural number following 776 and preceding 778. The number 777 is significant in numerous religious and political contexts.
In mathematics
777 is an odd, composite, palindromic repdigit. It is also a sphenic number, with 3, 7, and 37 as its prime factors. Its largest prime factor is a concatenation of its smaller two; the only other number below 1000 with this property is 138.
777 is also:
An extravagant number, a lucky number, a polite number, and an amenable number.
A deficient number, since the sum of its divisors is less than 2n.
A congruent number, as it is possible to make a right triangle with a rational number of sides whose area is 777.
An arithmetic number, since the average of its positive divisors is also an integer (152).
A repdigit in senary.
Religious significance
According to the Bible, Lamech, the father of Noah lived for 777 years. Some of the known religious connections to 777 are noted in the sections below.
Judaism
The numbers 3 and 7 both are considered "perfect numbers" under Hebrew tradition.
Christianity
According to the American publication, the Orthodox Study Bible, 777 represents the threefold perfection of the Trinity.
Thelema
777 is also found in the title of the book 777 and Other Qabalistic Writings of Aleister Crowley pertaining to the law of thelema.
Political significance
Afrikaner Weerstandsbeweging
The Afrikaner Resistance Movement (Afrikaner Weerstandsbeweging, AWB), a Boer-nationalist, neo-Nazi, and white supremacist movement in South Africa, used the number 777 as part of their emblem.
The number refers to a triumph of "God's number" 7 over the Devil's number 666. On the AWB flag, the numbers are arranged in a triskelion shape, resembling the Nazi swastika.
Computing
In Unix's chmod, change-access-mode command, the octal value 777 grants all file-access permissions to all user types in a file.
Commercial
Aviation
Boeing, the largest manufacturer of airliners in
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https://en.wikipedia.org/wiki/Akkermansia
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Akkermansia is a genus in the phylum Verrucomicrobiota (Bacteria). The genus was first proposed by Derrien et al. (2004), with the type species Akkermansia muciniphila (gen. nov., sp. nov).
Etymology
The name Akkermansia derives from:Neo-Latin feminine gender noun Akkermansia, named after Anton Dirk Louis Akkermans (28 October 1940 – 21 August 2006), a Dutch microbiologist recognized for his contribution to microbial ecology.
Until 2016 the genus contained a single known species, namely A. muciniphila (Derrien et al. 2004, (type species of the genus).; Neo-Latin neuter gender noun mucinum, mucin; Neo-Latin adjective philus from Greek adjective philos (φίλος) meaning friend, loving; Neo-Latin feminine gender adjective muciniphila, mucin-loving). However, de Vos et al. isolated a novel species in the feces of a reticulated python, Akkermansia glycaniphila.
Description of Akkermansia gen. nov.
Akkermansia (Ak.ker.man'si.a. N.L. fem. n. Akkermansia derived from Antoon Akkermans, a Dutch microbiologist recognized for his contribution to microbial ecology). Cells are oval-shaped, non-motile and stain Gram-negative. Strictly anaerobic organism. Chemo-organotrophic. Mucolytic in pure culture.
Phylogeny
The currently accepted taxonomy is based on the List of Prokaryotic names with Standing in Nomenclature (LPSN) and National Center for Biotechnology Information (NCBI)
Human metabolism
Akkermansia muciniphila can reside in the human intestinal tract and is currently being studied for its effects on human metabolism and health.
See also
Bacterial taxonomy
Human microbiota
Microbiology
List of bacterial orders
List of bacteria genera
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