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https://en.wikipedia.org/wiki/Spherical%20shell | In geometry, a spherical shell is a generalization of an annulus to three dimensions. It is the region of a ball between two concentric spheres of differing radii.
Volume
The volume of a spherical shell is the difference between the enclosed volume of the outer sphere and the enclosed volume of the inner sphere:
where is the radius of the inner sphere and is the radius of the outer sphere.
Approximation
An approximation for the volume of a thin spherical shell is the surface area of the inner sphere multiplied by the thickness of the shell:
when is very small compared to ().
The total surface area of the spherical shell is .
See also
Spherical pressure vessel
Ball
Solid torus
Bubble
Sphere |
https://en.wikipedia.org/wiki/Subbase | In topology, a subbase (or subbasis, prebase, prebasis) for a topological space with topology is a subcollection of that generates in the sense that is the smallest topology containing as open sets. A slightly different definition is used by some authors, and there are other useful equivalent formulations of the definition; these are discussed below.
Definition
Let be a topological space with topology A subbase of is usually defined as a subcollection of satisfying one of the two following equivalent conditions:
The subcollection generates the topology This means that is the smallest topology containing : any topology on containing must also contain
The collection of open sets consisting of all finite intersections of elements of together with the set forms a basis for This means that every proper open set in can be written as a union of finite intersections of elements of Explicitly, given a point in an open set there are finitely many sets of such that the intersection of these sets contains and is contained in
(If we use the nullary intersection convention, then there is no need to include in the second definition.)
For subcollection of the power set there is a unique topology having as a subbase. In particular, the intersection of all topologies on containing satisfies this condition. In general, however, there is no unique subbasis for a given topology.
Thus, we can start with a fixed topology and find subbases for that topology, and we can also start with an arbitrary subcollection of the power set and form the topology generated by that subcollection. We can freely use either equivalent definition above; indeed, in many cases, one of the two conditions is more useful than the other.
Alternative definition
Less commonly, a slightly different definition of subbase is given which requires that the subbase cover In this case, is the union of all sets contained in This means that there can be no confusion regardin |
https://en.wikipedia.org/wiki/ATRAC%20CD | An ATRAC CD is an optical disc containing compressed digital audio in the ATRAC3 or ATRAC3plus formats, which are part of Sony's ATRAC (Adaptive Transform Acoustic Coding) family of proprietary audio compression algorithms.
Description
ATRAC CD was used with SonicStage Simple Burner software (Ver.1.0 / 1.1) in February 2003, and was subsequently replaced with SonicStage in 2004. The new CD Walkman product was called "ATRAC CD Walkman". In the following year (2004-2005), ATRAC CD boombox was introduced as a new product.
*1 "ATRAC" here refers to the SP mode used in the MD format.
Software for burning ATRAC CD
The ATRAC CD can be burned with SonicStage Simple Burner Ver.1.1, SonicStage 2.x to 3.x and SonicStage CP. This software is able to create a disk image from MP3 files and compact discs, and can be burned with the included CD-R/RW drive on a computer.
See also
Walkman
SonicStage
ATRAC
OpenMG
Hi-MD |
https://en.wikipedia.org/wiki/Brownout%20%28software%20engineering%29 | Brownout in software engineering is a technique that involves disabling certain features of an application.
Description
Brownout is used to increase the robustness of an application to computing capacity shortage. If too many users are simultaneously accessing an application hosted online, the underlying computing infrastructure may become overloaded, rendering the application unresponsive. Users are likely to abandon the application and switch to competing alternatives, hence incurring long-term revenue loss. To better deal with such a situation, the application can be given brownout capabilities: The application will disable certain features – e.g., an online shop will no longer display recommendations of related products – to avoid overload. Although reducing features generally has a negative impact on the short-term revenue of the application owner, long-term revenue loss can be avoided.
The technique is inspired by brownouts in power grids, which consists in reducing the power grid's voltage in case electricity demand exceeds production. Some consumers, such as incandescent light bulbs, will dim – hence originating the term – and draw less power, thus helping match demand with production. Similarly, a brownout application helps match its computing capacity requirements to what is available on the target infrastructure.
Brownout complements elasticity. The former can help the application withstand short-term capacity shortage, but does so without changing the capacity available to the application. In contrast, elasticity consists of adding (or removing) capacity to the application, preferably in advance, so as to avoid capacity shortage altogether. The two techniques can be combined; e.g., brownout is triggered when the number of users increases unexpectedly until elasticity can be triggered, the latter usually requiring minutes to show an effect.
Brownout is relatively non-intrusive for the developer, for example, it can be implemented as an advice in asp |
https://en.wikipedia.org/wiki/Coarea%20formula | In the mathematical field of geometric measure theory, the coarea formula expresses the integral of a function over an open set in Euclidean space in terms of integrals over the level sets of another function. A special case is Fubini's theorem, which says under suitable hypotheses that the integral of a function over the region enclosed by a rectangular box can be written as the iterated integral over the level sets of the coordinate functions. Another special case is integration in spherical coordinates, in which the integral of a function on Rn is related to the integral of the function over spherical shells: level sets of the radial function. The formula plays a decisive role in the modern study of isoperimetric problems.
For smooth functions the formula is a result in multivariate calculus which follows from a change of variables. More general forms of the formula for Lipschitz functions were first established by Herbert Federer , and for functions by .
A precise statement of the formula is as follows. Suppose that Ω is an open set in and u is a real-valued Lipschitz function on Ω. Then, for an L1 function g,
where Hn−1 is the (n − 1)-dimensional Hausdorff measure. In particular, by taking g to be one, this implies
and conversely the latter equality implies the former by standard techniques in Lebesgue integration.
More generally, the coarea formula can be applied to Lipschitz functions u defined in taking on values in where k ≤ n. In this case, the following identity holds
where Jku is the k-dimensional Jacobian of u whose determinant is given by
Applications
Taking u(x) = |x − x0| gives the formula for integration in spherical coordinates of an integrable function f:
Combining the coarea formula with the isoperimetric inequality gives a proof of the Sobolev inequality for W1,1 with best constant:
where is the volume of the unit ball in
See also
Sard's theorem
Smooth coarea formula |
https://en.wikipedia.org/wiki/Ethoxyquin | Ethoxyquin (EMQ) is a quinoline-based antioxidant used as a food preservative in certain countries and originally to control scald on pears after harvest (under commercial names such as "Stop-Scald"). It is used as a preservative in some pet foods to slow the development of rancidity of fats. Ethoxyquin is also used in some spices to prevent color loss due to oxidation of the natural carotenoid pigments.
Regulation
Ethoxyquin was developed by Monsanto in the 1950s. Ethoxyquin was initially registered as a pesticide in 1965 as an antioxidant used as a deterrent of scald in pears through post-harvest indoor application via a drench and/or impregnated wrap.
As an antioxidant to control the browning of pears, ethoxyquin is approved in the United States and in the European Union.
In the United States, it is approved for use as an animal feed additive and is limited as a food additive to use only in the spices chili powder, paprika, and ground chili. Ethoxyquin is not permitted for use as food additive in Australia nor within the European Union.
Ethoxyquin is allowed in the fishing industry in Norway and France as a feed stabilizer, so is commonly used in food pellets fed to farmed salmon.
Norway made this practice illegal when the EU suspended authorization in 2017 and in accordance with the suspension utilized a transition period which allowed the sale of feed containing ethoxyquin until December 31st 2019, after this date it was illegal to sell feed containing ethoxyquin. Feed containing ethoxyquin had to be used by June 20th 2020.
Ethoxyquin is used in pellets fed to chickens on chicken farms.
In 2017 the EU suspended authorization for use as a feed additive, with various dates between 2017 and 2019 for final allowance of sale of goods so that alternatives may be phased in.
Safety
Some speculation exists that ethoxyquin in pet foods might be responsible for multiple health problems. To date, the U.S. Food and Drug Administration has only found a verifiable |
https://en.wikipedia.org/wiki/Xilinx%20ISE | Xilinx ISE (Integrated Synthesis Environment) is a discontinued software tool from Xilinx for synthesis and analysis of HDL designs, which primarily targets development of embedded firmware for Xilinx FPGA and CPLD integrated circuit (IC) product families. It was succeeded by Xilinx Vivado. Use of the last released edition from October 2013 continues for in-system programming of legacy hardware designs containing older FPGAs and CPLDs otherwise orphaned by the replacement design tool, Vivado Design Suite.
ISE enables the developer to synthesize ("compile") their designs, perform timing analysis, examine RTL diagrams, simulate a design's reaction to different stimuli, and configure the target device with the programmer. Other components shipped with the Xilinx ISE include the Embedded Development Kit (EDK), a Software Development Kit (SDK) and ChipScope Pro. The Xilinx ISE is primarily used for circuit synthesis and design, while ISIM or the ModelSim logic simulator is used for system-level testing.
As commonly practiced in the commercial electronic design automation sector, Xilinx ISE is tightly-coupled to the architecture of Xilinx's own chips (the internals of which are highly proprietary) and cannot be used with FPGA products from other vendors. Given the highly proprietary nature of the Xilinx hardware product lines, it is rarely possible to use open source alternatives to tooling provided directly from Xilinx, although as of 2020, some exploratory attempts are being made.
Legacy status
Since 2012, Xilinx ISE has been discontinued in favor of Vivado Design Suite that serves the same roles as ISE with additional features for system on a chip development.
Xilinx released the last version of ISE in October 2013 (version 14.7), and states that "ISE has moved into the sustaining phase of its product life cycle, and there are no more planned ISE releases."
User Interface
The primary user interface of the ISE is the Project Navigator, which includes the design hie |
https://en.wikipedia.org/wiki/Tetrachlorodecaoxide | "Tetrachlorodecaoxide" (TCDO) is a chlorite-containing substance with claimed immunomodulatory, macrophage-activating properties. WF10 (Macrokine, Immunokine, Oxoferin) is an aqueous solution of tetrachlorodecaoxide designed for intravenous injection. Tetrachlorodecaoxide/WF10 were originally developed by Oxo Chemie. The chemical formula is given as Cl4H2O114-. This incomplete formula shows a mixture of chlorite ion, water, and molecular oxygen: "Cl4H2O114-" = 4ClO2− + H2O + O2. Oxoferin was found to be equivalent with aqueous sodium chlorite.
Tetrachlorodecaoxide / WF10 is used in the management of radiation cystitis, is effective in the treatment of diabetic foot ulcers, and is used in wound healing, where the mechanism of action is activation of the macrophage system, and increasing the partial pressure of oxygen in the wound. |
https://en.wikipedia.org/wiki/Legacy%20port | In computing, a legacy port is a computer port or connector that is considered by some to be fully or partially superseded. The replacement ports usually provide most of the functionality of the legacy ports with higher speeds, more compact design, or plug and play and hot swap capabilities for greater ease of use. Modern PC motherboards use separate Super I/O controllers to provide legacy ports, since current chipsets do not offer direct support for them. A category of computers called legacy-free PCs omits these ports, typically retaining only USB for external expansion.
USB adapters are often used to provide legacy ports if they are required on systems not equipped with them.
Common legacy ports
See also
Legacy encoding
Legacy system |
https://en.wikipedia.org/wiki/Magnetic%20Drum%20Digital%20Differential%20Analyzer | The MADDIDA (Magnetic Drum Digital Differential Analyzer) was a special-purpose digital computer used for solving systems of ordinary differential equations. It was the first computer to represent bits using voltage levels and whose entire logic was specified in Boolean algebra.
Invented by Floyd Steele, MADDIDA was developed at Northrop Aircraft Corporation between 1946 and 1949 to be used as a guidance system for the Snark missile. No guidance system, however, resulted from the work on the MADDIDA, and rather it was used for aeronautical research. In 1952, the MADDIDA became the world's top-selling commercial digital computer (albeit a special-purpose machine), six units having been sold. (The general-purpose UNIVAC I delivered its seventh unit in 1954.)
Development
Development on the project began in March 1946 at Northrop Corporation with the goal of producing a subsonic cruise missile designated "MX-775", which came to be called the Snark. Northrop's parameters for this project were to create a guidance system that would allow a missile to hit a target at a distance of up to with a precision that would be better than the German "vengeance" weapons V1 and V2. However, the MADDIDA was never used in weaponry, and Northrop ultimately used a different analog computer as the guidance system for the Snark missile.
Part of the project parameters involved developing the first digital data analyzer (DIDA).
Physicist Floyd Steele, who had reportedly in 1946 already demonstrated a working DIDA before the press in 1946 in his Los Angeles home, was hired as conceptual leader of the design group. Steele developed the concept for the DIDA, which would entail implementing an analog computer using only digital elements. When the decision was made to use magnetic drum memory (MAD) for the DIDA, the name was lengthened to MADDIDA (pronounced "Mad Ida").
In his design for MADDIDA, Steele was influenced by the analog computer invented in 1927 by Vannevar Bush, which had |
https://en.wikipedia.org/wiki/Nakayama%27s%20conjecture | In mathematics, Nakayama's conjecture is a conjecture about Artinian rings, introduced by . The generalized Nakayama conjecture is an extension to more general rings, introduced by . proved some cases of the generalized Nakayama conjecture.
Nakayama's conjecture states that if all the modules of a minimal injective resolution of an Artin algebra R are injective and projective, then R is self-injective. |
https://en.wikipedia.org/wiki/Wilhelm%20Ahrens | Wilhelm Ahrens (3 March 1872 – 23 May 1927) was a German mathematician and writer on recreational mathematics.
Biography
Ahrens was born in Lübz at the Elde in Mecklenburg and studied from 1890 to 1897 at the University of Rostock, Humboldt University of Berlin, and the University of Freiburg. In 1895 at the University of Rostock he received his Promotion (Ph.D.), summa cum laude, under the supervision of Otto Staude with dissertation entitled Über eine Gattung n-fach periodischer Functionen von n reellen Veränderlichen. From 1895 to 1896 he taught at the German school in Antwerp and then studied another semester under Sophus Lie in Leipzig. In 1897 Ahrens was a teacher in Magdeburg at the Baugewerkeschule, from 1901 at the engineering school. Inspired by Sophus Lie, he wrote "On transformation groups, all of whose subgroups are invariant" (Hamburger Math Society Vol 4, 1902).
He worked a lot on the history of mathematics and mathematical games (recreational mathematics), about which he wrote a great work and also contributed to the Encyclopedia of mathematical sciences His predecessors were the great Jacques Ozanam in France, where the number theorist Édouard Lucas (1842–1891) in the 19th century wrote similar books, and Walter William Rouse Ball (1850–1925) in England (Mathematical recreations and essays 1892), Sam Loyd (1841–1901) in the U.S. and Henry Dudeney (1857–1930) in England. In this sense Martin Gardner (1914-2010) and Ian Stewart, the editor of the math column in Scientific American, might be regarded as his successors. He also wrote a book of quotations and anecdotes about mathematicians. He was the author of numerous journal articles.
Scherz und Ernst in der Mathematik
According to R. C. Archibald:
Bibliography
Mathematische Unterhaltungen und Spiele [Mathematical Recreations and Games], 1901
Mathematische Spiele [Mathematical Games], 1902
Scherz und Ernst in der Mathematik; geflügelte und ungeflügelte Worte [Fun and seriousness in mathem |
https://en.wikipedia.org/wiki/Recurrence%20relation | In mathematics, a recurrence relation is an equation according to which the th term of a sequence of numbers is equal to some combination of the previous terms. Often, only previous terms of the sequence appear in the equation, for a parameter that is independent of ; this number is called the order of the relation. If the values of the first numbers in the sequence have been given, the rest of the sequence can be calculated by repeatedly applying the equation.
In linear recurrences, the th term is equated to a linear function of the previous terms. A famous example is the recurrence for the Fibonacci numbers,
where the order is two and the linear function merely adds the two previous terms. This example is a linear recurrence with constant coefficients, because the coefficients of the linear function (1 and 1) are constants that do not depend on . For these recurrences, one can express the general term of the sequence as a closed-form expression of . As well, linear recurrences with polynomial coefficients depending on are also important, because many common elementary and special functions have a Taylor series whose coefficients satisfy such a recurrence relation (see holonomic function).
Solving a recurrence relation means obtaining a closed-form solution: a non-recursive function of .
The concept of a recurrence relation can be extended to multidimensional arrays, that is, indexed families that are indexed by tuples of natural numbers.
Definition
A recurrence relation is an equation that expresses each element of a sequence as a function of the preceding ones. More precisely, in the case where only the immediately preceding element is involved, a recurrence relation has the form
where
is a function, where is a set to which the elements of a sequence must belong. For any , this defines a unique sequence with as its first element, called the initial value.
It is easy to modify the definition for getting sequences starting from the term of index 1 |
https://en.wikipedia.org/wiki/White%20sapote | The white sapote, scientific name Casimiroa edulis, also called casimiroa and Mexican apple, and known as cochitzapotl in the Nahuatl language (meaning "sleep-sapote") is a species of tropical fruiting tree in the family Rutaceae, native to eastern Mexico and Central America south to Costa Rica. The genus is named for "an Otomi Indian, Casimiro Gómez, from the town of Cardonal in Hidalgo, Mexico, who fought and died in Mexico's war of independence."
Description
Mature C. edulis trees range from tall and are evergreen. The leaves are alternate, palmately compound with three to five leaflets, the leaflets 6–13 cm long and 2.5–5 cm broad with an entire margin, and the leaf petiole 10–15 cm long.
The fruit is an ovoid drupe, 5–10 cm in diameter, with a thin, inedible skin turning from green to yellow when ripe, and an edible pulp, which can range in flavor from bland to banana-like to peach to pear to vanilla flan. The pulp can be creamy-white in green-skin varieties or a beige-yellow in yellow-skin varieties and has a smooth texture similar to ripe avocado. It contains from one to five seeds that are said to have narcotic properties.
Chemical constituents
In the past 40 years, experiments carried out on the white sapote's seeds have identified many pharmacologically active compounds, including: N-methylhistamine, N,N-dimethylhistamine, and histamine. It also contains 2,5,6-trimethoxyflavone, 2, 6',5,6,-tetramethoxyflavone (zapotin), and 5-hydroxy-2,6,7-trimethoxyflavone (zapotinin).
Health effects
Several in vitro studies have shown that zapotin has potential anticarcinogenic effects against isolated colon cancer cells.
The fruit has long been thought to produce drowsiness, as claimed by Francisco Hernández de Toledo in the 16th century, but this may be a misinterpretation of the Nahuatl name of the plant, cochitzapotl (meaning '"sleep-sapote"), as its seeds were processed to produce a poison by the Aztecs, and the seeds and leaves, but not fruit pulp of the |
https://en.wikipedia.org/wiki/Whitley%20Professor%20of%20Biochemistry | The position of Whitley Professor of Biochemistry at the University of Oxford is one of the permanent chairs of the university, and the first in the field of biochemistry at the university. It is associated with a fellowship at Trinity College, Oxford, and was established with an endowment of £10,000 by Edward Whitley of Trinity College. Benjamin Moore was nominated by Whitley, a former student of Moore, as the first professor. Since its creation, the position has been held by:
Benjamin Moore 1920–22
Sir Rudolph Peters 1923–54
Sir Hans Adolf Krebs 1954–67
Rodney Robert Porter 1967–85
Sir Edwin Southern 1985–2005
Kim Nasmyth 2006-2022
Dame Amanda Fisher 2023 onwards |
https://en.wikipedia.org/wiki/Pinball%20FX%203 | Pinball FX 3 is a pinball simulator video game developed and published by Zen Studios and is the sequel to Pinball FX 2. It was released for Microsoft Windows, Xbox One, PlayStation 4 in September 2017 and then released for the Nintendo Switch in December 2017. A followup called Pinball FX was released in February 16, 2023.
Gameplay
Pinball FX 3 allows players to play one of several simulated pinball tables, and includes online scoreboard support for informal competition with other players. The game is aimed to provide a more engaging multiplayer experience than previous titles; the game will provide support for asynchronous competitive multiplayer options, and tournament-style play. There will be shared leaderboards and multiplayer options among platforms, although PlayStation 4 players can only compete with users playing through Steam on Windows due to Sony's initial decision to prohibit cross-platform play between its PlayStation 4 and other consoles.
Development
Zen's prior games have been split across consoles. The Pinball FX games typically have been released on Microsoft platforms, while the Zen Pinball games were released on non-Microsoft platforms. Pinball FX 3 will be the first game in the series to target both Microsoft and non-Microsoft platforms, and Zen intends that any future titles in the series will do so as well. Zen has stated that a "majority" of the previous downloadable content pinball tables that a player has purchased for either Pinball FX 2 or Zen Pinball 2 will be available in Pinball FX 3 at no cost; Zen cited issues with licensing that prevents some tables from being brought to the new version. Zen Studios has affirmed that more than fifty tables will carry over, with only about half a dozen that will not.
Pinball FX 3 launched with three new tables based on movie properties from Universal Pictures that includes E.T. the Extra-Terrestrial, Back to the Future, and Jaws. Additional tables are in development with new intellectual prope |
https://en.wikipedia.org/wiki/Phalaenopsis%20%C3%97%20leucorrhoda | Phalaenopsis × leucorrhoda is a species of orchid native to the Philippines. It is a natural hybrid of Phalaenopsis aphrodite and Phalaenopsis schilleriana.
Etymology
The specific epithet leucorrhoda, composed of leuco meaning white and rhodo meaning rose-coloured, is derived from the floral colouration.
Taxonomy
It has been confused with Phalaenopsis philippinensis, from which it differs in regard to the morphology of the callus of the labellum. |
https://en.wikipedia.org/wiki/Heptadecagon | In geometry, a heptadecagon, septadecagon or 17-gon is a seventeen-sided polygon.
Regular heptadecagon
A regular heptadecagon is represented by the Schläfli symbol {17}.
Construction
As 17 is a Fermat prime, the regular heptadecagon is a constructible polygon (that is, one that can be constructed using a compass and unmarked straightedge): this was shown by Carl Friedrich Gauss in 1796 at the age of 19. This proof represented the first progress in regular polygon construction in over 2000 years. Gauss's proof relies firstly on the fact that constructibility is equivalent to expressibility of the trigonometric functions of the common angle in terms of arithmetic operations and square root extractions, and secondly on his proof that this can be done if the odd prime factors of , the number of sides of the regular polygon, are distinct Fermat primes, which are of the form for some nonnegative integer . Constructing a regular heptadecagon thus involves finding the cosine of in terms of square roots. Gauss's book Disquisitiones Arithmeticae gives this (in modern notation) as
Constructions for the regular triangle, pentagon, pentadecagon, and polygons with 2h times as many sides had been given by Euclid, but constructions based on the Fermat primes other than 3 and 5 were unknown to the ancients. (The only known Fermat primes are Fn for n = 0, 1, 2, 3, 4. They are 3, 5, 17, 257, and 65537.)
The explicit construction of a heptadecagon was given by Herbert William Richmond in 1893. The following method of construction uses Carlyle circles, as shown below. Based on the construction of the regular 17-gon, one can readily construct n-gons with n being the product of 17 with 3 or 5 (or both) and any power of 2: a regular 51-gon, 85-gon or 255-gon and any regular n-gon with 2h times as many sides.
Another construction of the regular heptadecagon using straightedge and compass is the following:
T. P. Stowell of Rochester, N. Y., responded to Query, by W.E. Heal, Wheeli |
https://en.wikipedia.org/wiki/One%20Through%20Zero%20%28The%20Ten%20Numbers%29 | One Through Zero (The Ten Numbers) is a monumental series of sculptures by the American artist Robert Indiana. The work depicts the numerical digits 1, 2, 3, 4, 5, 6, 7, 8, and 9 and 0. The work was created between 1980 and 2001. The numbers are made from polychrome aluminium with each measuring 72 x 72 x 36 in. (182.9 x 182.9 x 91.4 cm.).
The use of numbers became prominent in Indiana's artworks from the end of the 1950s and became an established part of his style in the 1960s. The design of the numbers was inspired by a printer's calendar Indiana found in his loft in Coenties Slip. The piece was first created for a property developer in Indianapolis; the work was then donated to the Indianapolis Museum of Art. The work was subsequently created for a siting in Park Avenue in New York City in 2003 as part of the 'Art on the Park' series, outside Beverly Hills City Hall in 2005, and on Lime Street, London from 2013 as part of the City of London's 'Sculpture in the City' series. An edition of One Through Zero (The Ten Numbers) made from COR-TEN steel was displayed in London's Regent's Park in 2019.
Indiana had previously created a work with the poet Robert Creeley of a book of poems with poems about each number facing Indiana's screen printed coloured numbers.
Interpretation and meaning
The digits can be arranged in any order to generate new meanings and interpretations.
Indiana ascribed particular meanings to the colours that he chose for each digit.
Indiana's website ascribes the meanings as:
One: Red and blue, associated with birth
Two: Green and blue, signifying infancy
Three: Orange and blue representing youth
Four: Yellow and red, connected to adolescence
Five: White and blue signifying the 'pre-prime' of life
Six: Green and red signifying the prime of life
Seven: Blue and orange suggesting the 'early autumn' of life
Eight: Purple and red signalling autumn
Nine: Black and yellow conveying a sense of warning
Ten: The use of grey signals the end of the biolo |
https://en.wikipedia.org/wiki/Pollen-presenter | A pollen-presenter is an area on the tip of the style in flowers of plants of the family Proteaceae on which the anthers release their pollen prior to anthesis. To ensure pollination, the style grows during anthesis, sticking out the pollen-presenter prominently, and so ensuring that the pollen easily contacts the bodies of potential pollination vectors such as bees, birds and nectarivorous mammals. The systematic depositing of pollen on the tip of the style implies the plants have some strategy to avoid excessive self-pollination. |
https://en.wikipedia.org/wiki/MAFA | MAFA (Mast cell function-associated antigen) is a type II membrane glycoprotein, first identified on the surface of rat mucosal-type mast cells of the RBL-2H3 line. More recently, human and mouse homologues of MAFA have been discovered yet also (or only) expressed by NK and T-cells. MAFA is closely linked with the type 1 Fcɛ receptors in not only mucosal mast cells of humans and mice but also in the serosal mast cells of these same organisms.
It has the ability to function as both a channel for calcium ions along with interact with other receptors to inhibit certain cell processes. It function is based on its specialized structure, which contains many specialized motifs and sequences that allow its functions to take place.
Discovery
Experimental discovery
MAFA was initially discovered by Enrique Ortega and Israel Pecht in 1988 while studying the type 1 Fcɛ receptors (FcɛRI) and the unknown Ca2+ channels that allowed these receptors to work in the cellular membrane. Ortega and Pecht experimented through using a series of monoclonal antibodies on the RBL -2H3 line of rat mast cells. While experimenting and trying to find a specific antibody that would raise a response, the G63 monoclonal antibody was shown to raise a response by inhibiting the cellular secretions linked to the FcɛRI receptors in these rat mucosal mast cells. The G63 antibody attached to a specific membrane receptor protein that caused the inhibition process to occur. Specifically, the inhibition occurred by the G63 antibody and glycoprotein cross-linking so that the processes of inflammation mediator formation, Ca2+ intake into the cell, and the hydrolysis of phosphatidylinositides were all stopped. This caused biochemical inhibition of the normal FcɛRI response. The identified receptor protein was then isolated and studied where it was found that when cross-linked, the protein actually had a conformational change that localized the FcɛRI receptors. Based on these results, both Ortega and Pecht na |
https://en.wikipedia.org/wiki/Extremal%20optimization | Extremal optimization (EO) is an optimization heuristic inspired by the Bak–Sneppen model of self-organized criticality from the field of statistical physics. This heuristic was designed initially to address combinatorial optimization problems such as the travelling salesman problem and spin glasses, although the technique has been demonstrated to function in optimization domains.
Relation to self-organized criticality
Self-organized criticality (SOC) is a statistical physics concept to describe a class of dynamical systems that have a critical point as an attractor. Specifically, these are non-equilibrium systems that evolve through avalanches of change and dissipations that reach up to the highest scales of the system. SOC is said to govern the dynamics behind some natural systems that have these burst-like phenomena including landscape formation, earthquakes, evolution, and the granular dynamics of rice and sand piles. Of special interest here is the Bak–Sneppen model of SOC, which is able to describe evolution via punctuated equilibrium (extinction events) – thus modelling evolution as a self-organised critical process.
Relation to computational complexity
Another piece in the puzzle is work on computational complexity, specifically that critical points have been shown to exist in NP-complete problems, where near-optimum solutions are widely dispersed and separated by barriers in the search space causing local search algorithms to get stuck or severely hampered. It was the evolutionary self-organised criticality model by Bak and Sneppen and the observation of critical points in combinatorial optimisation problems that lead to the development of Extremal Optimization by Stefan Boettcher and Allon Percus.
The technique
EO was designed as a local search algorithm for combinatorial optimization problems. Unlike genetic algorithms, which work with a population of candidate solutions, EO evolves a single solution and makes local modifications to the worst comp |
https://en.wikipedia.org/wiki/Remote%20diagnostics | Remote diagnostics is the act of diagnosing a given symptom, issue or problem from a distance. Instead of the subject being co-located with the person or system done diagnostics, with remote diagnostics the subjects can be separated by physical distance (e.g., Earth-Moon). Important information is exchanged either through wire or wireless.
When limiting to systems, a general accepted definition is:
"To improve reliability of vital or capital-intensive installations and reduce the maintenance costs by avoiding unplanned maintenance, by monitoring the condition of the system remotely."
Process elements for remote diagnostics
Remotely monitor selected vital system parameters
Analysis of data to detect trends
Comparison with known or expected behavior data
After detected performance degradation, predict the failure moment by extrapolation
Order parts and/or plan maintenance, to be executed when really necessary, but in time to prevent a failure or stop
Typical uses
Medical use (see Remote guidance)
Formula One racecars
Space (Apollo project and others)
Telephone systems like a PABX
Connected Cars (https://en.wikipedia.org/wiki/Connected_car)
Reasons for use
Limit local personnel to a minimum (Gemini, Apollo capsules: too tight to fit all technicians)
Limit workload of local personnel
Limit risks (exposure to dangerous environments)
Central expertise (locally solve small problems, remotely/centralized solve complex problems by experts)
Efficiency: reduce travel time to get expert and system or subject together
Remote diagnostics and maintenance
Remote diagnostics and maintenance refers to both diagnoses of the fault or faults and taking corrective (maintenance) actions, like changing settings to improve performance or prevent problems like breakdown, wear and tear. RDM can replace manpower at location by experts on a central location, in order to save manpower or prevent hazardous situations (space for instance). Increasing globalisation and more an |
https://en.wikipedia.org/wiki/Single-ended%20triode | A single-ended triode (SET) is a vacuum tube electronic amplifier that uses a single triode to produce an output, in contrast to a push-pull amplifier which uses a pair of devices with antiphase inputs to generate an output with the wanted signals added and the distortion components subtracted. Single-ended amplifiers normally operate in Class A; push-pull amplifiers can also operate in Classes AB or B without excessive net distortion, due to cancellation.
The term single-ended triode amplifier is mainly used for output stages of audio power amplifiers.
The phrase directly heated triode single-ended triode amplifier (abbreviated to DHT SET) is used when directly heated triodes are used.
There are also single-ended tetrode, beam tetrode/beam power tube/kinkless tetrode, and pentode amplifiers with the same functionality and similar circuitry; e.g. this Mullard design.
Audio power amplifiers
A typical triode audio power amplifier will have a driver that provides voltage gain, coupled to a triode (like 2A3 and 300B) or a pentode or kinkless tetrode such as EL34 or KT88 connected as a triode, connected to the loudspeaker through an audio transformer in a common cathode arrangement. The triode is biased to Class A operation by applying a suitable negative bias voltage to its input control grid (see diagram), or by raising the cathode potential with biasing components.
In traditional SET amp, the direct current of output triode (from 30 mA for triode-strapped 6V6 to 250 mA for 6C33C) flows continuously through the primary winding of a transformer. This requires inserting a gap in the transformer core to prevent core saturation by DC current; adding a gap decreases primary inductance and limits bass response; the inductance and bass response can be restored by using a larger transformer than if the DC were not present.
An alternative schematic, parafeed amplifier, solves bandwidth problem by blocking direct current from output transformer (which does not need to be |
https://en.wikipedia.org/wiki/Requirements%20analysis | In systems engineering and software engineering, requirements analysis focuses on the tasks that determine the needs or conditions to meet the new or altered product or project, taking account of the possibly conflicting requirements of the various stakeholders, analyzing, documenting, validating and managing software or system requirements.
Requirements analysis is critical to the success or failure of a systems or software project.<ref>{{cite book
|editor1= Alain Abran |editor2=James W. Moore |editor3=Pierre Bourque |editor4=Robert Dupuis
| title = Guide to the software engineering body of knowledge|url = http://www.swebok.org
|access-date = 2007-02-08|edition=2004 |date=March 2005
| publisher = IEEE Computer Society Press | location = Los Alamitos, CA | isbn = 0-7695-2330-7
| chapter = Chapter 2: Software Requirements | chapter-url = http://www.computer.org/portal/web/swebok/html/ch2
| quote = It is widely acknowledged within the software industry that software engineering projects are critically vulnerable when these activities are performed poorly.
}}</ref> The requirements should be documented, actionable, measurable, testable, traceable, related to identified business needs or opportunities, and defined to a level of detail sufficient for system design.
Overview
Conceptually, requirements analysis includes three types of activities:
Eliciting requirements: (e.g. the project charter or definition), business process documentation, and stakeholder interviews. This is sometimes also called requirements gathering or requirements discovery.
Recording requirements: Requirements may be documented in various forms, usually including a summary list and may include natural-language documents, use cases, user stories, process specifications and a variety of models including data models.
Analyzing requirements: determining whether the stated requirements are clear, complete, unduplicated, concise, valid, consistent and unambiguous, and resolving any apparent confl |
https://en.wikipedia.org/wiki/Spin%20echo%20small%20angle%20neutron%20scattering | Spin echo small angle neutron scattering (SESANS) measures structures from around 20 to 2000 nm in size. The information is presented as a real-space (similar to g(r)) as opposed to a reciprocal space (q(r)) mapping. This can simplify the interpretation for some systems.
SESANS is useful for studying processes that occur over relatively long time scales, as data collection is often slow, but large length scales. Aggregation of colloids, block copolymer micelles, Stöber silica particles being a prime examples.
The technique offers some advantages over SANS but there are fewer SESANS instruments available than SANS instruments. Facilities for SESANS exist at TUDelft (Netherlands) and Rutherford Appleton Laboratory (UK). |
https://en.wikipedia.org/wiki/Tripod%20stance | A tripod stance is a behaviour in which quadruped animals rear up on their hind legs and use their tail to support this position. Several animals use this behaviour to improve observation or surveillance, and during feeding, grooming, thermoregulation, or fighting.
In mammals
The common dwarf mongoose (Helogale parvula) adopts a tripod stance when being vigilant for predators. In a similar mammal, the thirteen-lined ground squirrel
(Spermophilus tridecemlineatus), vigilance behaviour includes four postures: (1) quadrupedal alert (all four feet on the ground with head above the horizontal); (2) semiupright alert (on hind feet with a distinctive slouch); (3) upright alert (on hind feet with back straight and mostly perpendicular to the ground); (4) extended upright alert (similar to upright alert except that the squirrel extends its hind legs, (see image of meerkats). In meerkats (Suricata suricatta), the tripod stance may be adopted relatively briefly during foraging, in which case it is termed guarding behaviour, or for substantially longer periods when the animal is not foraging, in which case it is termed sentinel behaviour.
Macropods can stand erect on their hind legs, supported by their tail as the third leg of the tripod. Macropods also engage in "pentapedal locomotion," an energy-inefficient gait used at slow speed, in which "the tail is used, with the forelimbs, as the third leg of a tripod to support the animal while the large hind limbs are moved forward."
Giant armadillos (Priodontes maximus) have a well-developed sense of smell but poor eyesight. When approached by a potential threat, they rise up onto their hind legs, supported by the tail and begin to sniff from side to side. This tripod stance is similar to the defensive position adopted by anteaters and enables them to strike out with their sharply-hooked claws if suddenly attacked.
It has been reported that the desert woodrat (Neotoma lepida) gives birth "...in a bipedal position supported by th |
https://en.wikipedia.org/wiki/Mir-615%20microRNA%20precursor%20family | mir-615 microRNA is a short non-coding RNA molecule belonging both to the family of microRNAs and to that of small interfering RNAs (siRNAs). MicroRNAs function to regulate the expression levels of other genes by several mechanisms, whilst siRNAs are involved primarily with the RNA interference (RNAi) pathway. siRNAs have been linked through some members to the regulation of cancer cell growth, specifically in prostate adenocarcinoma.
miR-615 and NGX6
Nasopharyngeal carcinoma-associated gene 6 (NGX6) acts as a tumour suppressor gene in colon cancer. miR-615 has been found to be downregulated in NGX6-transfected cells, although identification of its target genes has not yet been achieved.
Hox cluster conservation
miR-615 has been found to reside within Hox gene clusters, alongside Hox genes other miRNAs. Hox genes are involved in anterior-posterior axis patterning. miR-615 is located at the HOXC5 (encdoing the HOXC5 homeobox protein) intron in mammals.
See also
MicroRNA |
https://en.wikipedia.org/wiki/Antigenic%20drift | Antigenic drift is a kind of genetic variation in viruses, arising from the accumulation of mutations in the virus genes that code for virus-surface proteins that host antibodies recognize. This results in a new strain of virus particles that is not effectively inhibited by the antibodies that prevented infection by previous strains. This makes it easier for the changed virus to spread throughout a partially immune population. Antigenic drift occurs in both and viruses.
(Confusion can arise with two very similar terms, antigenic shift and genetic drift. Antigenic shift is a closely related process; it refers to the more dramatic changes in the virus's surface proteins when the genetic material from two or more viruses mix together. Genetic drift is very different and much more broadly applicable; it refers to the gradual accumulation in any DNA sequence of random mutational changes that do not interfere with the DNA's function and thus that are not seen by natural selection.)
The immune system recognizes viruses when antigens on the surfaces of virus particles bind to immune receptors that are specific for these antigens. These receptors can be antibodies in the bloodstream or similar proteins on the surfaces of immune-system cells. This recognition is quite precise, like a key recognizing a lock. After an infection or after vaccination, the body produces many more of these virus-specific immune receptors, which prevent re-infection by this particular strain of the virus; this is called acquired immunity. However, viral genomes are constantly mutating, producing new forms of these antigens. If one of these new forms of an antigen is sufficiently different from the old antigen, it will no longer bind to the antibodies or immune-cell receptors, allowing the mutant virus to infect people who were immune to the original strain of the virus because of prior infection or vaccination.
In 1940s, Maurice Hilleman discovered antigenic drift, which is the most common |
https://en.wikipedia.org/wiki/Halloween%20genes | The halloween genes are a set of genes identified in Drosophila melanogaster that influence embryonic development. All of the genes code for cytochrome P450 enzymes in the ecdysteroidogenic pathway (biosynthesis of ecdysone from cholesterol). Ecdysteroids such as 20-hydroxyecdysone and ecdysone influence many of the morphological, physiological, biochemical changes that occur during molting in insects.
Steroid hormones control many aspects of reproduction, development, and homeostasis in higher organisms. In arthropods, steroid hormones play equal or even more vital developmental roles, especially in controlling the patterns of gene expression between developmental stages. The forerunner of steroid hormones is cholesterol that vertebrates can synthesize. In contrast, insects need to take up cholesterol in their diet. In 20E biosynthesis, a series of hydroxylation takes place and the genes that encoded the enzymes for catalyzing the hydroxylation were first identified in Drosphilia. Insects have been around since about 500 million years before the first mammal and have continued to be evolutionarily successful. This suggests that exogenous cholesterol was required for the mechanism for steroid hormone biosynthesis.
First elaborated by research groups led by Wieschaus and Nüsslein-Volhard in the early 1980s, the name was coined to collectively name a series of Drosophila embryonic lethal mutations associated with defective exoskeleton formation. Early research showed that when one of the Halloween genes was mutated, fly embryos would die before the exoskeleton was created. Mutants in the halloween gene series include the spook, spookier, phantom (or phm), disembodied (or dib), shadow (or sad), and shade genes.
The mutant homozygous embryos appear phenotypically normal until mid-embryonic development where the embryos exhibit abnormal developmental characters. Some abnormal characteristics include undifferentiated cuticle, a failure of head involution, dorsal closu |
https://en.wikipedia.org/wiki/Martin%20Hairer | Sir Martin Hairer (born 14 November 1975) is an Austrian-British mathematician working in the field of stochastic analysis, in particular stochastic partial differential equations. He is Professor of Mathematics at EPFL (École Polytechnique Fédérale de Lausanne) and at Imperial College London. He previously held appointments at the University of Warwick and the Courant Institute of New York University. In 2014 he was awarded the Fields Medal, one of the highest honours a mathematician can achieve. In 2020 he won the 2021 Breakthrough Prize in Mathematics.
Early life and education
Hairer was born in Geneva, Switzerland. He attended the Collège Claparède Geneva where he received his high school diploma in 1994. He entered a school science competition with sound editing software that was developed into Amadeus,
and later continued to maintain the software in addition to his academic work; it continued to be widely used . He then attended the University of Geneva, where he obtained his Bachelor of Science degree in Mathematics in July 1998, Master of Science in Physics in October 1998 and PhD in Physics under the supervision of Jean-Pierre Eckmann in November 2001.
Research and career
Hairer is active in the field of stochastic partial differential equations in particular, and in stochastic analysis and stochastic dynamics in general. He has worked on variants of Hörmander's theorem, systematisation of the construction of Lyapunov functions for stochastic systems, development of a general theory of ergodicity for non-Markovian systems, multiscale analysis techniques, theory of homogenisation, theory of path sampling and theory of rough paths and, in 2014, on his theory of regularity structures.
Under the name HairerSoft, he develops Macintosh software.
Affiliations
Regius Professor of Mathematics, University of Warwick (2014–2017)
Member of the scientific steering committee of ETHZ-ITS (2013–2019)
Institut Henri Poincaré, member of scientific steering committee |
https://en.wikipedia.org/wiki/Agnes%20Pockels | Agnes Luise Wilhelmine Pockels (14 February 1862 – 21 November 1935) was a German chemist whose research was fundamental in establishing the modern discipline known as surface science, which describes the properties of liquid and solid surfaces and interfaces.
Pockels became interested in fundamental research in surface science through observations of soaps and soapy water in her own home while washing dishes. She devised a surface film balance technique to study the behavior of molecules such as soaps and surfactants at air-liquid interfaces. From these studies, Pockels defined the "Pockels Point" which is the minimum area that a single molecule can occupy in monomolecular films.
Pockels was an autodidact. She was not a paid, professional scientist and had no institutional affiliation and so is an example of a citizen scientist.
Early life and education
Pockels was born in Venice, Austrian Empire, in 1862. At the time, Venice was under Austrian rule, and Pockels' father served in the Austrian Army. When he fell sick, the family moved in 1871 to Brunswick, which was part of the nascent German Empire. There, Pockels attended the Municipal High School for Girls. Agnes was interested in chemistry as a child. However, women were not allowed to enter universities to study. Pockels stated that "I had a passionate interest in natural science, especially physics, and would have liked to study.“ (Agnes Pockels, as translated by Giles from Autobiographical Notes in W. Ostwald, 1932.)
As a child, Pockels was interested in science, especially physics. In those days, women in Germany had no access to universities. Pockels studied science at home while caring for her parents. Pockels' younger brother Friedrich Carl Alwin Pockels studied physics at the University of Göttingen, completing his degree there. Friedrich shared textbooks from the university with Agnes Pockels in order to help her study from home. He later shared academic literature with Agnes Pockels to advance her |
https://en.wikipedia.org/wiki/Worms%3F | Worms? is a software toy written by David Maynard for the Atari 8-bit family and ported to the Commodore 64. Published by Electronic Arts in 1983, it was one of initial batch of releases from the company. Worms? is an interactive version of Paterson's Worms.
Maynard later worked on the 8-bit word processor from Electronic Arts, Cut & Paste. On March 17, 2021, the source code to Worms? was made available under the MIT License.
Gameplay
The game is abstract, like Conway's Game of Life, but the player's ostensible goal is to optimally program one or more worms (each a sort of cellular automaton) to grow and survive as long as possible. The game area is divided up into hexagonal cells, and the worms are programmed to move in a particular direction for each combination of filled-in and empty frame segments in their immediate vicinity. Over the course of a game, the player needs to give the worm less and less input, and more and more moves by the worm results in the encountering of a familiar situation for which the worm has already been trained. As the worms move, they generate aleatoric music.
Development
When David Maynard finished developing the game for his Atari 800 in the fall of 1982, it was titled Sumo Worms. It was written in the Forth programming language.
Reception
Allen Doum reviewed the game for Computer Gaming World, and stated that "Worms? can be played competitively, either by teams or individuals or can be used solitaire as a pattern drawing puzzle. Its sound and graphics are excellent, and some of the graphics elements and the speed of the game can be varied." Orson Scott Card in Compute! gave complimentary reviews to the EA games Worms?, M.U.L.E., and Archon: The Light and the Dark. He said of the trio that "they are original; they do what they set out to do very, very well; they allow the player to take part in the creativity; they do things that only computers can do". William Michael Brown for Electronic Fun with Computers & Games praised its o |
https://en.wikipedia.org/wiki/Pertechnetate | The pertechnetate ion () is an oxyanion with the chemical formula . It is often used as a convenient water-soluble source of isotopes of the radioactive element technetium (Tc). In particular it is used to carry the 99mTc isotope (half-life 6 hours) which is commonly used in nuclear medicine in several nuclear scanning procedures.
A technetate(VII) salt is a compound containing this ion. Pertechnetate compounds are salts of technetic(VII) acid. Pertechnetate is analogous to permanganate but it has little oxidizing power. Pertechnetate has higher oxidation power than perrhenate.
Understanding pertechnetate is important in understanding technetium contamination in the environment and in nuclear waste management.
Chemistry
is the starting material for most of the chemistry of technetium. Pertechnetate salts are usually colorless. is produced by oxidizing technetium with nitric acid or with hydrogen peroxide. The pertechnetate anion is similar to the permanganate anion but is a weaker oxidizing agent. It is tetrahedral and diamagnetic. The standard electrode potential for / is only +0.738 V in acidic solution, as compared to +1.695 V for /. Because of its diminished oxidizing power, is stable in alkaline solution. is more similar to . Depending on the reducing agent, can be converted to derivatives containing Tc(VI), Tc(V), and Tc(IV). In the absence of strong complexing ligands, is reduced to a +4 oxidation state via the formation of hydrate.
Preparation of 99mTcO4−
is conveniently available in high radionuclidic purity from molybdenum-99, which decays with 87% probability to . The subsequent decay of leads to either or . can be produced in a nuclear reactor via irradiation of either molybdenum-98 or naturally occurring molybdenum with thermal neutrons, but this is not the method currently in use today. Currently, is recovered as a product of the nuclear fission reaction of , separated from other fission products via a multistep process and loaded ont |
https://en.wikipedia.org/wiki/IP%20set | In mathematics, an IP set is a set of natural numbers which contains all finite sums of some infinite set.
The finite sums of a set D of natural numbers are all those numbers that can be obtained by adding up the elements of some finite nonempty subset of D.
The set of all finite sums over D is often denoted as FS(D). Slightly more generally, for a sequence of natural numbers (ni), one can consider the set of finite sums FS((ni)), consisting of the sums of all finite length subsequences of (ni).
A set A of natural numbers is an IP set if there exists an infinite set D such that FS(D) is a subset of A. Equivalently, one may require that A contains all finite sums FS((ni)) of a sequence (ni).
Some authors give a slightly different definition of IP sets: They require that FS(D) equal A instead of just being a subset.
The term IP set was coined by Hillel Furstenberg and Benjamin Weiss to abbreviate "infinite-dimensional parallelepiped". Serendipitously, the abbreviation IP can also be expanded to "idempotent" (a set is an IP if and only if it is a member of an idempotent ultrafilter).
Hindman's theorem
If is an IP set and , then at least one is an IP set.
This is known as Hindman's theorem or the finite sums theorem. In different terms, Hindman's theorem states that the class of IP sets is partition regular.
Since the set of natural numbers itself is an IP set and partitions can also be seen as colorings, one can reformulate a special case of Hindman's theorem in more familiar terms: Suppose the natural numbers are "colored" with n different colors; each natural number gets one and only one color. Then there exists a color c and an infinite set D of natural numbers, all colored with c, such that every finite sum over D also has color c.
Hindman's theorem is named for mathematician Neil Hindman, who proved it in 1974.
The Milliken–Taylor theorem is a common generalisation of Hindman's theorem and Ramsey's theorem.
Semigroups
The definition of being IP has be |
https://en.wikipedia.org/wiki/Oscheius%20tipulae | Oscheius tipulae is a species of nematodes, described in association of the leatherjacket, the larva of Tipula paludosa.
O. tipulae is a satellite developmental genetic model organism used to study vulva formation. It is an androdioecious species characterized by the coexistence of males and hermaphrodites. |
https://en.wikipedia.org/wiki/Coumarin | Coumarin () or 2H-chromen-2-one is an aromatic organic chemical compound with formula . Its molecule can be described as a benzene molecule with two adjacent hydrogen atoms replaced by an unsaturated lactone ring , forming a second six-membered heterocycle that shares two carbons with the benzene ring. It belongs to the benzopyrone chemical class and considered as a lactone.
Coumarin is a colorless crystalline solid with a sweet odor resembling the scent of vanilla and a bitter taste. It is found in many plants, where it may serve as a chemical defense against predators. By inhibiting synthesis of vitamin K, a related compound is used as the prescription drug warfarin – an anticoagulant – to inhibit formation of blood clots, deep vein thrombosis, and pulmonary embolism.
Etymology
Coumarin is derived from coumarou, the French word for the tonka bean. The word tonka for the tonka bean is taken from the Galibi (Carib) tongue spoken by natives of French Guiana (one source for the plant); it also appears in Old Tupi, another language of the same region, as the name of the tree. The old genus name, Coumarouna, was formed from another Tupi name for tree, kumarú.
History
Coumarin was first isolated from tonka beans in 1820 by A. Vogel of Munich, who initially mistook it for benzoic acid.
Also in 1820, Nicholas Jean Baptiste Gaston Guibourt (1790–1867) of France independently isolated coumarin, but he realized that it was not benzoic acid. In a subsequent essay he presented to the pharmacy section of the Académie Royale de Médecine, Guibourt named the new substance coumarine.
In 1835, the French pharmacist A. Guillemette proved that Vogel and Guibourt had isolated the same substance. Coumarin was first synthesized in 1868 by the English chemist William Henry Perkin.
Coumarin has been an integral part of the fougère genre of perfume since it was first used in Houbigant's Fougère Royale in 1882.
Synthesis
Coumarin can be prepared by a number of name reactions, with |
https://en.wikipedia.org/wiki/Impromptu%20%28programming%20environment%29 | Impromptu is a Mac OS X programming environment for live coding. Impromptu is built around the Scheme language, which is a member of the Lisp family of languages. The source code of its core has been opened as the Extempore project.
Description
The environment allows to make changes to a program at runtime, so variables and functions may be redefined and the changes take effect immediately. A programmer can also create and schedule code for future execution, as well as data events such as notes and graphics objects. Once an event is scheduled, execution continues. Looping is performed by using an idiom called "temporal recursion" which works by having a function asynchronously schedule a future call to itself as its final action.
The library allows communicating with Audio Units for audio synthesis, and with graphics layers such as QuickTime, Quartz, Core Image, OpenGL for video composition. Code written in Objective-C can be called from the editor, and also Objective-C frameworks can perform calls to the Scheme interpreter.
Impromptu's Scheme interpreter was initially built from the TinyScheme 1.35 baseline, but it has been substantially modified since to better suit the live coding context. A real-time garbage collector, and Objective-C integration were added. Also, a new statically typed language called the Extempore Language has been integrated to the system. This language is syntactically Scheme-like, but semantically closer to C, and is designed for real-time sound synthesis and other computationally heavy tasks. It provides type inference and is compiled to machine language by LLVM.
Sample performance
A Study in Keith is a live coding performance in Impromptu by Andrew Sorensen. The first two minutes (1:56) are silent, while the performer writes the program that will produce the introduction of the piece. From then on, he modifies the code on the fly to evolve the composition.
Extempore
The core of Impromptu has been released as Extempore under a |
https://en.wikipedia.org/wiki/ActiveVOS | ActiveVOS is a business process management suite. Business processes are designed using the graphical BPMN 2.0 notation. The process engine implements the WS-BPEL 2.0 standard as well as BPEL4People for processes that require people to perform tasks from a task list. |
https://en.wikipedia.org/wiki/Double-well%20potential | The so-called double-well potential is one of a number of quartic potentials of considerable interest in quantum mechanics, in quantum field theory and elsewhere for the exploration of various physical phenomena or mathematical properties since it permits in many cases explicit calculation without over-simplification.
Thus the "symmetric double-well potential" served for many years as a model to illustrate the concept of instantons as a pseudo-classical configuration in a Euclideanised field theory. In the simpler quantum mechanical context this potential served as a model for the evaluation of Feynman path integrals. or the solution of the Schrödinger equation by various methods for the purpose of obtaining explicitly the energy eigenvalues.
The "inverted symmetric double-well potential", on the other hand, served as a nontrivial potential in the Schrödinger equation for the calculation of decay rates and the exploration of the large order behavior of asymptotic expansions.
The third form of the quartic potential is that of a "perturbed simple harmonic oscillator" or ″pure anharmonic oscillator″ having a purely discrete energy spectrum.
The fourth type of possible quartic potential is that of "asymmetric shape" of one of the first two named above.
The double-well and other quartic potentials can be treated by a variety of methods—the main methods being (a) a perturbation method (that of B. Dingle and H.J.W. Müller-Kirsten) which requires the imposition of boundary conditions, (b) the WKB method and (c) the path integral method..
All cases are treated in detail in the book of H.J.W. Müller-Kirsten. The large order behavior of asymptotic expansions of Mathieu functions and their eigenvalues (also called characteristic numbers) has been derived in a further paper of R.B. Dingle and H.J.W. Müller.
The symmetric double-well
The main interest in the literature has (for reasons related to field theory) focused on the symmetric double-well (potential), and there on t |
https://en.wikipedia.org/wiki/Garou%3A%20Mark%20of%20the%20Wolves | is a 1999 fighting game produced by SNK, originally for the Neo Geo system and then as Fatal Fury: Mark of the Wolves for the Dreamcast. It is the eighth (or ninth if one counts Fatal Fury: Wild Ambition) installment of the Fatal Fury series.
Gameplay
The two-plane system in which characters would fight from two different planes was removed from the game. The game introduces the "Tactical Offense Position" (T.O.P.), which is a special area on the life gauge. When the gauge reaches this area, the character enters the T.O.P. mode, granting the player's character the ability to use a T.O.P. attack, gradual life recovery, and increased attack damage. The game also introduces the "Just Defend" system, which rewards the player who successfully blocks an attack at the last moment with a small amount of health recovery and the ability to immediately counterattack out of block stun. Just Defend was later added as a feature of the K-Groove in Capcom's Capcom vs. SNK 2. Similar to previous titles, the player is given a fighting rank after every round. If the player manages to win all rounds from the Arcade Mode with at least an "AAA" rank, they will face the boss Kain R. Heinlein, which unlocks an ending after he is defeated. If the requirements are not met, then Grant will be the final boss and there will be no special endings. Additionally, through Arcade Mode, before facing Grant, the player will face a mid-boss which can be any character from the cast depending on the character they use.
Playable characters
Plot
Ten years after crime lord Geese Howard's death, the city of Southtown has become more peaceful, leading it to be known as the Second Southtown in reference to having formerly been corrupted by Geese. A new fighting tournament called "King of Fighters: Maximum Mayhem" starts in the area, and several characters related with the fighters from the previous King of Fighters tournaments participate in it.
Development
Multiple changes to Garou were made to show a |
https://en.wikipedia.org/wiki/Neuronal%20calcium%20sensor | Neuronal Calcium Sensor is a large family of proteins which work as calcium dependent molecular switches and includes members like Frequenin (NCS1), recoverin, GCAP, neurocalcin, visinin etc. All the members carry 4 EF hand motifs (out of which only 2 or 3 bind calcium) and an N-myristoyl group.
Members of NCS family
Highly evolutionarily conserved
NCS1 (Frequenin)
VILIP-1 (Visinin-like-protein-1)
HPCAL4 (Visinin-like-protein-2)
HPCAL1 (Visinin-like-protein-3)
hippocalcin
neurocalcin
recoverin
Guanylate cyclase activator proteins (GCAPs)
Potassium Channel interacting proteins (KChIPs 1–4), including:
KCNIP1,
KCNIP2,
Calsenilin or DREAM/KChIP-3/KCNIP3 (downstream regulatory element antagonist modulator/potassium channel interacting protein),
KCNIP4 |
https://en.wikipedia.org/wiki/Chorion | The chorion is the outermost fetal membrane around the embryo in mammals, birds and reptiles (amniotes). It develops from an outer fold on the surface of the yolk sac, which lies outside the zona pellucida (in mammals), known as the vitelline membrane in other animals. In insects it is developed by the follicle cells while the egg is in the ovary. Some mollusks also have chorions as part of their eggs. For example fragile octopus eggs have only a chorion as their envelope.
Structure
In humans and other mammals (excluding monotremes), the chorion is one of the fetal membranes that exist during pregnancy between the developing fetus and mother. The chorion and the amnion together form the amniotic sac. In humans it is formed by extraembryonic mesoderm and the two layers of trophoblast that surround the embryo and other membranes; the chorionic villi emerge from the chorion, invade the endometrium, and allow the transfer of nutrients from maternal blood to fetal blood.
Layers
The chorion consists of two layers: an outer formed by the trophoblast, and an inner formed by the somatic mesoderm.
The trophoblast is made up of an internal layer of cubical or prismatic cells, the cytotrophoblast or layer of Langhans, and an external multinucleated layer, the syncytiotrophoblast.
Growth
The chorion undergoes rapid proliferation and forms numerous processes, the chorionic villi, which invade and destroy the uterine decidua, while simultaneously absorbing nutritive materials from it for the growth of the embryo.
The chorionic villi are at first small and non-vascular, and consist of the trophoblast only, but they increase in size and ramify, whereas the mesoderm, carrying branches of the umbilical vessels, grows into them, and they are vascularized.
Blood is carried to the villi by the paired umbilical arteries, which branch into chorionic arteries and enter the chorionic villi as cotyledon arteries. After circulating through the capillaries of the villi, the blood is |
https://en.wikipedia.org/wiki/Kaplan%E2%80%93Yorke%20conjecture | In applied mathematics, the Kaplan–Yorke conjecture concerns the dimension of an attractor, using Lyapunov exponents. By arranging the Lyapunov exponents in order from largest to smallest , let j be the largest index for which
and
Then the conjecture is that the dimension of the attractor is
This idea is used for the definition of the Lyapunov dimension.
Examples
Especially for chaotic systems, the Kaplan–Yorke conjecture is a useful tool in order to estimate the fractal dimension
and the Hausdorff dimension of the corresponding attractor.
The Hénon map with parameters a = 1.4 and b = 0.3 has the ordered Lyapunov exponents and . In this case, we find j = 1 and the dimension formula reduces to
The Lorenz system shows chaotic behavior at the parameter values , and . The resulting Lyapunov exponents are {2.16, 0.00, −32.4}. Noting that j = 2, we find |
https://en.wikipedia.org/wiki/Raphael%20Douady | Raphael Douady (born 15 November 1959) is a French mathematician and economist. He holds the Robert Frey Endowed Chair for Quantitative Finance at Stony Brook, New York. He is a fellow of the Centre d’Economie de la Sorbonne (Economic Centre of Sorbonne), Paris 1 Pantheon-Sorbonne University, and academic director of the Laboratory of Excellence on Financial Regulation (Labex Refi).
Early life and education
Douady is the son of mathematician Adrien Douady (1935–2006). He is an alumnus of Ecole Normale Supérieure, where he placed first in the entrance exam. He later ranked first in the Agrégation de mathématiques in 1980. He earned his PhD in the fields of Hamiltonian systems in 1982 at the Paris Diderot University (Paris 7), while still a student at ENS, under the guidance of Michael Herman.
Career
In 1983, Douady was appointed to the Centre National de la Recherche Scientifique (CNRS). He was affiliated with Ecole Polytechnique (1983–87), Ecole Normale Supérieure (1987–95), the Courant Institute at New York University (1995–97), Ecole Normale Supérieure of Cachan (1997–2001), and a former visiting professor at New York University Polytechnic Institute. In 2001, he founded Riskdata, a private software company, remaining with them until 2011 since when he has been affiliated to Paris 1 Pantheon-Sorbonne University.
In 1994, he created and animated the Bachelier Seminar of mathematical finance at Institut Henri Poincaré in Paris. He is also the co-founder, with Marco Avellaneda, of the Seminar of Mathematical Finance held at the Courant Institute of Mathematical Science, New York University. He has advised financial institutions including Société Générale, National Westminster Bank, Canadian Imperial Bank of Commerce and Citibank.
In 1999, along with Ingmar Adlerberg, a computer scientist from the French Institute for Research in Computer Science and Automation (INRIA) and the Massachusetts Institute of Technology (MIT), Douady co-founded Riskdata, a company produ |
https://en.wikipedia.org/wiki/RFQ%20beam%20cooler | A radio-frequency quadrupole (RFQ) beam cooler is a device for particle beam cooling, especially suited for ion beams. It lowers the temperature of a particle beam by reducing its energy dispersion and emittance, effectively increasing its brightness (brilliance). The prevalent mechanism for cooling in this case is buffer-gas cooling, whereby the beam loses energy from collisions with a light, neutral and inert gas (typically helium). The cooling must take place within a confining field in order to counteract the thermal diffusion that results from the ion-atom collisions.
The quadrupole mass analyzer (a radio frequency quadrupole used as a mass filter) was invented by Wolfgang Paul in the late 1950s to early 60s at the University of Bonn, Germany. Paul shared the 1989 Nobel Prize in Physics for his work. Samples for mass analysis are ionized, for example by laser (matrix-assisted laser desorption/ionization) or discharge (electrospray or inductively coupled plasma) and the resulting beam is sent through the RFQ and "filtered" by scanning the operating parameters (chiefly the RF amplitude). This gives a mass spectrum, or fingerprint, of the sample. Residual gas analyzers use this principle as well.
Applications of ion cooling to nuclear physics
Despite its long history, high-sensitivity high-accuracy mass measurements of atomic nuclei continue to be very important areas of research for many branches of physics. Not only do these measurements provide a better understanding of nuclear structures and nuclear forces but they also offer insight into how matter behaves in some of Nature's harshest environments. At facilities such as ISOLDE at CERN and TRIUMF in Vancouver, for instance, measurement techniques are now being extended to short-lived radionuclei that only occur naturally in the interior of exploding stars. Their short half-lives and very low production rates at even the most powerful facilities require the very highest in sensitivity of such measurements. |
https://en.wikipedia.org/wiki/Tate%E2%80%93Shafarevich%20group | In arithmetic geometry, the Tate–Shafarevich group of an abelian variety (or more generally a group scheme) defined over a number field consists of the elements of the Weil–Châtelet group , where is the absolute Galois group of , that become trivial in all of the completions of (i.e., the real and complex completions as well as the -adic fields obtained from by completing with respect to all its Archimedean and non Archimedean valuations ). Thus, in terms of Galois cohomology, can be defined as
This group was introduced by Serge Lang and John Tate and Igor Shafarevich. Cassels introduced the notation , where is the Cyrillic letter "Sha", for Shafarevich, replacing the older notation or .
Elements of the Tate–Shafarevich group
Geometrically, the non-trivial elements of the Tate–Shafarevich group can be thought of as the homogeneous spaces of that have -rational points for every place of , but no -rational point. Thus, the group measures the extent to which the Hasse principle fails to hold for rational equations with coefficients in the field . Carl-Erik Lind gave an example of such a homogeneous space, by showing that the genus 1 curve has solutions over the reals and over all -adic fields, but has no rational points.
Ernst S. Selmer gave many more examples, such as .
The special case of the Tate–Shafarevich group for the finite group scheme consisting of points of some given finite order of an abelian variety is closely related to the Selmer group.
Tate-Shafarevich conjecture
The Tate–Shafarevich conjecture states that the Tate–Shafarevich group is finite. Karl Rubin proved this for some elliptic curves of rank at most 1 with complex multiplication. Victor A. Kolyvagin extended this to modular elliptic curves over the rationals of analytic rank at most 1 (The modularity theorem later showed that the modularity assumption always holds).
Cassels–Tate pairing
The Cassels–Tate pairing is a bilinear pairing , where is an abelian variety and is i |
https://en.wikipedia.org/wiki/Euclidean%20topology | In mathematics, and especially general topology, the Euclidean topology is the natural topology induced on -dimensional Euclidean space by the Euclidean metric.
Definition
The Euclidean norm on is the non-negative function defined by
Like all norms, it induces a canonical metric defined by The metric induced by the Euclidean norm is called the Euclidean metric or the Euclidean distance and the distance between points and is
In any metric space, the open balls form a base for a topology on that space.
The Euclidean topology on is the topology by these balls.
In other words, the open sets of the Euclidean topology on are given by (arbitrary) unions of the open balls defined as for all real and all where is the Euclidean metric.
Properties
When endowed with this topology, the real line is a T5 space.
Given two subsets say and of with where denotes the closure of there exist open sets and with and such that
See also |
https://en.wikipedia.org/wiki/Momentum%20transfer | In particle physics, wave mechanics, and optics, momentum transfer is the amount of momentum that one particle gives to another particle. It is also called the scattering vector as it describes the transfer of wavevector in wave mechanics.
In the simplest example of scattering of two colliding particles with initial momenta , resulting in final momenta , the momentum transfer is given by
where the last identity expresses momentum conservation. Momentum transfer is an important quantity because is a better measure for the typical distance resolution of the reaction than the momenta themselves.
Wave mechanics and optics
A wave has a momentum and is a vectorial quantity. The difference of the momentum of the scattered wave to the incident wave is called momentum transfer. The wave number k is the absolute of the wave vector and is related to the wavelength . Momentum transfer is given in wavenumber units in reciprocal space
Diffraction
The momentum transfer plays an important role in the evaluation of neutron, X-ray, and electron diffraction for the investigation of condensed matter. Laue-Bragg diffraction occurs on the atomic crystal lattice, conserves the wave energy and thus is called elastic scattering, where the wave numbers final and incident particles, and , respectively, are equal and just the direction changes by a reciprocal lattice vector with the relation to the lattice spacing . As momentum is conserved, the transfer of momentum occurs to crystal momentum.
The presentation in reciprocal space is generic and does not depend on the type of radiation and wavelength used but only on the sample system, which allows to compare results obtained from many different methods. Some established communities such as powder diffraction employ the diffraction angle as the independent variable, which worked fine in the early years when only a few characteristic wavelengths such as Cu-K were available. The relationship to -space is
with and basically states tha |
https://en.wikipedia.org/wiki/Carlos%20Matheus | Carlos Matheus Silva Santos (born May 1, 1984 in Aracaju) is a Brazilian mathematician working in dynamical systems, analysis and geometry. He currently works at the CNRS, in Paris.
He earned his Ph.D. from the Instituto de Matemática Pura e Aplicada (IMPA) in 2004 under the supervision of Marcelo Viana, at the age of 19.
Selected publications
with G. Forni, and A. Zorich: "Square-tiled cyclic covers", Journal of Modern Dynamics, vol. 5, no. 2, pp. 285–318 (2011).
with A. Avila, and J.-C. Yoccoz: "SL(2,R)-invariant probability measures on the moduli spaces of translation surfaces are regular", Geometric and Functional Analysis, vol. 23, no. 6, pp. 1705–1729 (2013).
with M. Möller, and J.-C. Yoccoz: "A criterion for the simplicity of the Lyapunov spectrum of square-tiled surfaces", ''Inventiones mathematicae (2014).
Further reading
Época – Os segredos das ilhas de excelência (by Carlos Rydlewski, in Portuguese) |
https://en.wikipedia.org/wiki/Surgery%20structure%20set | In mathematics, the surgery structure set is the basic object in the study of manifolds which are homotopy equivalent to a closed manifold X. It is a concept which helps to answer the question whether two homotopy equivalent manifolds are diffeomorphic (or PL-homeomorphic or homeomorphic). There are different versions of the structure set depending on the category (DIFF, PL or TOP) and whether Whitehead torsion is taken into account or not.
Definition
Let X be a closed smooth (or PL- or topological) manifold of dimension n. We call two homotopy equivalences from closed manifolds of dimension to () equivalent if there exists a cobordism together with a map such that , and are homotopy equivalences.
The structure set is the set of equivalence classes of homotopy equivalences from closed manifolds of dimension n to X.
This set has a preferred base point: .
There is also a version which takes Whitehead torsion into account. If we require in the definition above the homotopy equivalences F, and to be simple homotopy equivalences then we obtain the simple structure set .
Remarks
Notice that in the definition of resp. is an h-cobordism resp. an s-cobordism. Using the s-cobordism theorem we obtain another description for the simple structure set , provided that n>4: The simple structure set is the set of equivalence classes of homotopy equivalences from closed manifolds of dimension n to X with respect to the following equivalence relation. Two homotopy equivalences (i=0,1) are equivalent if there exists a
diffeomorphism (or PL-homeomorphism or homeomorphism) such that is homotopic to .
As long as we are dealing with differential manifolds, there is in general no canonical group structure on . If we deal with topological manifolds, it is possible to endow with a preferred structure of an abelian group (see chapter 18 in the book of Ranicki).
Notice that a manifold M is diffeomorphic (or PL-homeomorphic or homeomorphic) to a closed manifold X |
https://en.wikipedia.org/wiki/George%20F.%20D.%20Duff | George Francis Denton Duff (July 29, 1926 – March 2, 2001) was a Canadian mathematician who did research in partial differential equations and wave phenomena. He took an interest in harnessing the extraordinarily large tides in the Bay of Fundy for generating electricity.
While studying at the University of Toronto, Duff became a Putnam fellow in 1948. After that, Duff was a PhD student of Solomon Lefschetz at Princeton University. He became a professor at the University of Toronto in 1952. There, he supervised the Ph.D. theses of 13 students and served as chair of the Mathematics Department from 1968 to 1975.
Duff was the president of the Canadian Mathematical Society from 1971 to 1973. He was an Invited Plenary speaker at International Congress of Mathematicians in Vancouver in 1974. |
https://en.wikipedia.org/wiki/Rexx | Rexx (Restructured Extended Executor) is a programming language that can be interpreted or compiled. It was developed at IBM by Mike Cowlishaw. It is a structured, high-level programming language designed for ease of learning and reading. Proprietary and open source Rexx interpreters exist for a wide range of computing platforms; compilers exist for IBM mainframe computers.
Rexx is a full language that can be used as a scripting, macro language, and application development language. It is often used for processing data and text and generating reports; this means that Rexx works well in Common Gateway Interface (CGI) programming and is used for this purpose, like later languages such as Perl. Rexx is the primary scripting language in some operating systems, e.g. OS/2, MVS, VM, AmigaOS, and is also used as an internal macro language in some other software, such as SPF/PC, KEDIT, THE and the ZOC terminal emulator. Additionally, the Rexx language can be used for scripting and macros in any program that uses Windows Scripting Host ActiveX scripting engines languages (e.g. VBScript and JScript) if one of the Rexx engines is installed.
Rexx is supplied with VM/SP Release 3 on up, TSO/E Version 2 on up, OS/2 (1.3 and later, where it is officially named Procedures Language/2), AmigaOS Version 2 on up, PC DOS (7.0 or 2000), ArcaOS, and Windows NT 4.0 (Resource Kit: Regina). REXX scripts for CMS share the filetype EXEC with EXEC and EXEC2, and the first line of the script specifies the interpreter to be used. REXX scripts for MVS may be recognized by the low level qualifier EXEC or may be recognized by context and the first line. REXX scripts for OS/2 share the filename extension .cmd with other scripting languages, and the first line of the script specifies the interpreter to be used. REXX macros for REXX-aware applications use extensions determined by the application. In the late 1980s, Rexx became the common scripting language for IBM Systems Application Architecture, wh |
https://en.wikipedia.org/wiki/IEC%2062264 | IEC 62264 is an international standard for enterprise control system integration. This standard is based upon ANSI/ISA-95.
Current parts of IEC 62264
IEC 62264 consists of the following parts detailed in separate IEC 62264 standard documents:
Part 1:2013 Object Models and Attributes of Manufacturing Operations (Second edition 2013-05)
Part 2:2013 Object model attributes (Second edition 2013-06)
Part 3:2016 Activity models of manufacturing operations management (Second edition 2016-12)
Part 4:2015 Objects models attributes for manufacturing operations management integration
Part 5:2016 Business to manufacturing transactions
Publicly Available Specification - Pre-standard Part 6:2016 Messaging Service Model |
https://en.wikipedia.org/wiki/Vector%20measuring%20current%20meter | A vector measuring current meter (VMCM) is an instrument used for obtaining measurements of horizontal velocity in the upper ocean, which exploits two orthogonal cosine response propeller sensors that directly measure the components of horizontal velocity.
VMCM was developed in the late 1970s by Drs. Robert Weller and Russ Davis and commercially produced by EG&G Sealink System (currently EdgeTech).
The instrument has the capability of one year long deployment at depths of up to 5000 m. Both laboratory and field test results show that the VMCM is capable of making accurate measurements of horizontal velocity in the upper ocean. The VMCM is the current standard for making high quality velocity measurements in near-surface regions and it has been used for benchmarking other current meters.
Equipment
The main components of a VMCM are its two orthogonal cosine response propeller sensors, that directly measure the components of horizontal velocity parallel to their axes. The orientation of the instrument with respect to magnetic north is sensed with a flux-gate compass, which permits to evaluate the direction of flux, providing the angle of the Y axis with respect to the magnetic North.
A microprocessor rotates the X-Y coordinates in the conventional east–west and north–south components of velocity. This is done once each sample interval and, at the end of the record interval, the conventional components of velocity are averaged and the averages are stored on a cassette magnetic tape. Other components of the system are a bearing retainer, an end cap, an outer bearing race, a ball retainer and bearing balls, an encoder and an epoxy or Noryl plastic disk with four magnets, pressure window, an aluminum disk, two magnetodiodes mounted asymmetrically on a printed circuit ring, a hub, and a shaft with inner races machined in it. The function of the magnetodiodes is detecting the rotation of the propeller sensors.
Incorporated in the system there is the vector averaging elec |
https://en.wikipedia.org/wiki/Electrical%20reactance | In electrical circuits, reactance is the opposition presented to alternating current by inductance and capacitance. Along with resistance, it is one of two elements of impedance; however, while both elements involve transfer of electrical energy, no dissipation of electrical energy as heat occurs in reactance; instead, the reactance stores energy until a quarter-cycle later when the energy is returned to the circuit. Greater reactance gives smaller current for the same applied voltage.
Reactance is used to compute amplitude and phase changes of sinusoidal alternating current going through a circuit element. Like resistance, reactance is measured in ohms, with positive values indicating inductive reactance and negative indicating capacitive reactance. It is denoted by the symbol . An ideal resistor has zero reactance, whereas ideal inductors and capacitors have zero resistance. As frequency increases, inductive reactance increases and capacitive reactance decreases.
Comparison to resistance
Reactance is similar to resistance in that larger reactance leads to smaller currents for the same applied voltage. Further, a circuit made entirely of elements that have only reactance (and no resistance) can be treated the same way as a circuit made entirely of resistances. These same techniques can also be used to combine elements with reactance with elements with resistance but complex numbers are typically needed. This is treated below in the section on impedance.
There are several important differences between reactance and resistance, though. First, reactance changes the phase so that the current through the element is shifted by a quarter of a cycle relative to the phase of the voltage applied across the element. Second, power is not dissipated in a purely reactive element but is stored instead. Third, reactances can be negative so that they can 'cancel' each other out. Finally, the main circuit elements that have reactance (capacitors and inductors) have a frequency |
https://en.wikipedia.org/wiki/Average%20human%20height%20by%20country | Below are two tables which report the average adult human height by country or geographical region. With regard to the first table, original studies and sources should be consulted for details on methodology and the exact populations measured, surveyed, or considered. With regard to the second table, these estimated figures for said countries and territories in 2019 and the declared sources may conflict with the findings of the first table.
First table: individual surveys and studies
Accuracy
As with any statistical data, the accuracy of the findings may be challenged. In this case, for the following reasons:
Some studies may allow subjects to self-report values. Generally speaking, self-reported height tends to be taller than measured height, although the overestimation of height depends on the reporting subject's height, age, gender and region.
Test subjects may have been invited instead of chosen at random, resulting in sampling bias.
Some countries may have significant height gaps between different regions. For instance, one survey shows there is gap between the tallest state and the shortest state in Germany. Under such circumstances, the mean height may not represent the total population unless sample subjects are appropriately taken from all regions with using weighted average of the different regional groups.
Different social groups can show different mean height. According to a study in France, executives and professionals are taller, and university students are taller than the national average. As this case shows, data taken from a particular social group may not represent a total population in some countries.
Height can vary over the course of a day, due to factors such as a decrease from exercise done directly before measurement (i.e. inversely correlated), or an increase since lying down for a significant period of time (i.e. positively correlated). For example, one study revealed a mean decrease of in the heights of 100 children from gettin |
https://en.wikipedia.org/wiki/Advanced%20Vector%20Extensions | Advanced Vector Extensions (AVX) are extensions to the x86 instruction set architecture for microprocessors from Intel and Advanced Micro Devices (AMD). They were proposed by Intel in March 2008 and first supported by Intel with the Sandy Bridge processor shipping in Q1 2011 and later by AMD with the Bulldozer processor shipping in Q3 2011. AVX provides new features, new instructions, and a new coding scheme.
AVX2 (also known as Haswell New Instructions) expands most integer commands to 256 bits and introduces new instructions. They were first supported by Intel with the Haswell processor, which shipped in 2013.
AVX-512 expands AVX to 512-bit support using a new EVEX prefix encoding proposed by Intel in July 2013 and first supported by Intel with the Knights Landing co-processor, which shipped in 2016. In conventional processors, AVX-512 was introduced with Skylake server and HEDT processors in 2017.
Advanced Vector Extensions
AVX uses sixteen YMM registers to perform a single instruction on multiple pieces of data (see SIMD). Each YMM register can hold and do simultaneous operations (math) on:
eight 32-bit single-precision floating point numbers or
four 64-bit double-precision floating point numbers.
The width of the SIMD registers is increased from 128 bits to 256 bits, and renamed from XMM0–XMM7 to YMM0–YMM7 (in x86-64 mode, from XMM0–XMM15 to YMM0–YMM15). The legacy SSE instructions can be still utilized via the VEX prefix to operate on the lower 128 bits of the YMM registers.
AVX introduces a three-operand SIMD instruction format called VEX coding scheme, where the destination register is distinct from the two source operands. For example, an SSE instruction using the conventional two-operand form can now use a non-destructive three-operand form , preserving both source operands. Originally, AVX's three-operand format was limited to the instructions with SIMD operands (YMM), and did not include instructions with general purpose registers (e.g. EAX). I |
https://en.wikipedia.org/wiki/Axial%20ratio | Axial ratio, for any structure or shape with two or more axes, is the ratio of the length (or magnitude) of those axes to each other - the longer axis divided by the shorter.
In chemistry or materials science, the axial ratio (symbol P) is used to describe rigid rod-like molecules. It is defined as the length of the rod divided by the rod diameter.
In physics, the axial ratio describes electromagnetic radiation with elliptical, or circular, polarization. The axial ratio is the ratio of the magnitudes of the major and minor axis defined by the electric field vector.
See also
Aspect ratio
Degree of polarization
Ratios
Polymer physics |
https://en.wikipedia.org/wiki/List%20of%20hardware%20and%20software%20that%20supports%20FLAC | This is a list of computer hardware and software which supports FLAC (Free Lossless Audio Codec), a file format designed for lossless compression of digital audio.
Hardware support
Car devices
Alpine CDE-163BT
Alpine UTE-62BT
Citroën DS5
Hyundai Ioniq
Hyundai Kona
Kenwood KMM-100U
Peugeot 208 Blue Lion
Pioneer Avic-4100 -> 8100NEX
Pioneer DEH-X8700BH
Power Acoustik PD-622NB
Renault Espace
SEAT León
Sony MEX-N5100BT
Sony MEX-XB100BT
Sony XAV-AX1000
Tesla Models S/X/3/Y
DJ players
Pioneer CDJ-2000nexus2
Pioneer CDJ-TOUR1
Pioneer XDJ-1000mk2
Pioneer CDJ-3000
Pioneer XDJ-RX3
Pioneer XDJ-XZ (After firmware vers. 1.10)
Portable stereo / boombox
Active speakers
Fenda F&D A140X, F&D A180X
Logitech Z607 5.1
Home audio AV receivers / amplifiers
Bang and Olufsen BeoSound 5
Denon AVR-1612, AVR-2313, AVR-3310, AVR-3808, AVR-4308, AVR-4310, AVR-4311, AVR-4520A, AVR-4810, AVR-5308, AVP-A1HDCI, AVR-X1000, AVR-X2000, AVR-X3000, AVR-X4000, NP-720AE*Escient
Onkyo TX-8050, TX-SR309, TX-SR333, TX-NR535, TX-NR626, TX-NR636, TX-NR737, TX-NR838, TX-NR1030, TX-NR3030
Pioneer SC-05, SC-07, SC-25, SC-27, SC-35, SC-37, SC-09TX, X-HM76B, XC-HM86
Sonos 16-bit max.
Sony's High-Res Audio Players
Yamaha RX-A1000/A2000/A3000 AV Receiver, RX-V477, RX-V671, RX-V673 (RX-V773, RX-V671, RX-V673 – up to 96 kHz streaming and 192 kHz external link) AV Receivers, RX-V773, RX-V795, RX-V1067, RX-V2065 AV Receiver, RX-V2067, RX-V3067 AV Receivers
Home media servers and clients
Cambridge Audio CXN Network Player | Azur 851N Network Player
Dvico TVIX HD M-6500, N1 (cafe), HD M-6600A/N Plus, HD M-7000
Linn Klimax DS, Renew DS, Akurate DS, Majik DS and Sneaky Music DS
Logitech Squeezebox and Transporter network music players from Logitech. Current products decode natively, old v1 units transcode to PCM on the server. (discontinued)
Naim Audio HDX Hard Disk Player, NaimUniti, UnitiQute, DAC, NDX, UnitiServe
Meridian Sooloos
Pixel Magic Systems' HD Mediabox (with firmware 1 |
https://en.wikipedia.org/wiki/ISO%2019092-2 | ISO 19092 Financial Services - Biometrics - Part 2: Message syntax and cryptographic requirements is an ISO standard that describes the techniques, protocols, cryptographic requirements, and syntax for using biometrics as an identification and verification mechanism in a wide variety of security applications in the financial industry. This standard provides support for policy based matching decisions for remote authentication and allows biometrics to be used securely with the ISO 8583 retail transaction messaging standard. A secure review and audit event journal syntax is provided that allows many of the security controls specified in ISO 19092-1 to be implemented.
Cryptography standards
19092-2 |
https://en.wikipedia.org/wiki/Ideal%20%28set%20theory%29 | In the mathematical field of set theory, an ideal is a partially ordered collection of sets that are considered to be "small" or "negligible". Every subset of an element of the ideal must also be in the ideal (this codifies the idea that an ideal is a notion of smallness), and the union of any two elements of the ideal must also be in the ideal.
More formally, given a set an ideal on is a nonempty subset of the powerset of such that:
if and then and
if then
Some authors add a fourth condition that itself is not in ; ideals with this extra property are called .
Ideals in the set-theoretic sense are exactly ideals in the order-theoretic sense, where the relevant order is set inclusion. Also, they are exactly ideals in the ring-theoretic sense on the Boolean ring formed by the powerset of the underlying set. The dual notion of an ideal is a filter.
Terminology
An element of an ideal is said to be or , or simply or if the ideal is understood from context. If is an ideal on then a subset of is said to be (or just ) if it is an element of The collection of all -positive subsets of is denoted
If is a proper ideal on and for every either or then is a .
Examples of ideals
General examples
For any set and any arbitrarily chosen subset the subsets of form an ideal on For finite all ideals are of this form.
The finite subsets of any set form an ideal on
For any measure space, subsets of sets of measure zero.
For any measure space, sets of finite measure. This encompasses finite subsets (using counting measure) and small sets below.
A bornology on a set is an ideal that covers
A non-empty family of subsets of is a proper ideal on if and only if its in which is denoted and defined by is a proper filter on (a filter is if it is not equal to ). The dual of the power set is itself; that is, Thus a non-empty family is an ideal on if and only if its dual is a dual ideal on (which by definition is either the power |
https://en.wikipedia.org/wiki/Limit%20load%20%28physics%29 | Limit load is the maximum load that a structure can safely carry. It's the load at which the structure is in a state of incipient plastic collapse. As the load on the structure increases, the displacements increases linearly in the elastic range until the load attains the yield value. Beyond this, the load-displacement response becomes non-linear and the plastic or irreversible part of the displacement increases steadily with the applied load. Plasticity spreads throughout the solid and at the limit load, the plastic zone becomes very large and the displacements become unbounded and the component is said to have collapsed.
Any load above the limit load will lead to the formation of plastic hinge in the structure. Engineers use limit states to define and check a structure's performance.
Bounding Theorems of Plastic-Limit Load Analysis:
Plastic limit theorems provide a way to calculate limit loads without having to solve the boundary value problem in continuum mechanics. Finite element analysis provides an alternative way to estimate limit loads. They are:
The Upper Bound Plastic Collapse Theorem
The Lower Bound Plastic Collapse Theorem
The Lower Bound Shakedown Theorem
The Upper Bound Shakedown Theorem
The Upper Bound Plastic Collapse Theorem states that an upper bound to the collapse loads can be obtained by postulating a collapse mechanism and computing the ratio of its plastic dissipation to the work done by the applied loads. |
https://en.wikipedia.org/wiki/Circuit%20satisfiability%20problem | In theoretical computer science, the circuit satisfiability problem (also known as CIRCUIT-SAT, CircuitSAT, CSAT, etc.) is the decision problem of determining whether a given Boolean circuit has an assignment of its inputs that makes the output true. In other words, it asks whether the inputs to a given Boolean circuit can be consistently set to 1 or 0 such that the circuit outputs 1. If that is the case, the circuit is called satisfiable. Otherwise, the circuit is called unsatisfiable. In the figure to the right, the left circuit can be satisfied by setting both inputs to be 1, but the right circuit is unsatisfiable.
CircuitSAT is closely related to Boolean satisfiability problem (SAT), and likewise, has been proven to be NP-complete. It is a prototypical NP-complete problem; the Cook–Levin theorem is sometimes proved on CircuitSAT instead of on the SAT, and then CircuitSAT can be reduced to the other satisfiability problems to prove their NP-completeness. The satisfiability of a circuit containing arbitrary binary gates can be decided in time .
Proof of NP-Completeness
Given a circuit and a satisfying set of inputs, one can compute the output of each gate in constant time. Hence, the output of the circuit is verifiable in polynomial time. Thus Circuit SAT belongs to complexity class NP. To show NP-hardness, it is possible to construct a reduction from 3SAT to Circuit SAT.
Suppose the original 3SAT formula has variables , and operators (AND, OR, NOT) . Design a circuit such that it has an input corresponding to every variable and a gate corresponding to every operator. Connect the gates according to the 3SAT formula. For instance, if the 3SAT formula is the circuit will have 3 inputs, one AND, one OR, and one NOT gate. The input corresponding to will be inverted before sending to an AND gate with and the output of the AND gate will be sent to an OR gate with
Notice that the 3SAT formula is equivalent to the circuit designed above, hence their output is same f |
https://en.wikipedia.org/wiki/Lenia | Lenia is a family of cellular automata created by Bert Wang-Chak Chan. It is intended to be a continuous generalization of Conway's Game of Life, with continuous states, space and time. As a consequence of its continuous, high-resolution domain, the complex autonomous patterns ("lifeforms" or "spaceships") generated in Lenia are described as differing from those appearing in other cellular automata, being "geometric, metameric, fuzzy, resilient, adaptive, and rule-generic".
Lenia won the 2018 Virtual Creatures Contest at the Genetic and Evolutionary Computation Conference in Kyoto, an honorable mention for the ALIFE Art Award at ALIFE 2018 in Tokyo, and Outstanding Publication of 2019 by the International Society for Artificial Life (ISAL).
Rules
Iterative updates
Let be the lattice or grid containing a set of states . Like many cellular automata, Lenia is updated iteratively; each output state is a pure function of the previous state, such that
where is the initial state and is the global rule, representing the application of the local rule over every site . Thus .
If the simulation is advanced by at each timestep, then the time resolution .
State sets
Let with maximum . This is the state set of the automaton and characterizes the possible states that may be found at each site. Larger correspond to higher state resolutions in the simulation. Many cellular automata use the lowest possible state resolution, i.e. . Lenia allows for much higher resolutions. Note that the actual value at each site is not in but rather an integer multiple of ; therefore we have for all . For example, given , .
Neighborhoods
Mathematically, neighborhoods like those in Game of Life may be represented using a set of position vectors in . For the classic Moore neighborhood used by Game of Life, for instance, ; i.e. a square of size 3 centered on every site.
In Lenia's case, the neighborhood is instead a ball of radius centered on a site, , which may include the original |
https://en.wikipedia.org/wiki/Wavelet%20transform%20modulus%20maxima%20method | The wavelet transform modulus maxima (WTMM) is a method for detecting the fractal dimension of a signal.
More than this, the WTMM is capable of partitioning the time and scale domain of a signal into fractal dimension regions, and the method is sometimes referred to as a "mathematical microscope" due to its ability to inspect the multi-scale dimensional characteristics of a signal and possibly inform about the sources of these characteristics.
The WTMM method uses continuous wavelet transform rather than Fourier transforms to detect singularities – that is discontinuities, areas in the signal that are not continuous at a particular derivative.
In particular, this method is useful when analyzing multifractal signals, that is, signals having multiple fractal dimensions.
Description
Consider a signal that can be represented by the following equation:
where is close to and is a non-integer quantifying the local singularity. (Compare this to a Taylor series, where in practice only a limited number of low-order terms are used to approximate a continuous function.)
Generally, a continuous wavelet transform decomposes a signal as a function of time, rather than assuming the signal is stationary (For example, the Fourier transform). Any continuous wavelet can be used, though the first derivative of the Gaussian distribution and the Mexican hat wavelet (2nd derivative of Gaussian) are common. Choice of wavelet may depend on characteristics of the signal being investigated.
Below we see one possible wavelet basis given by the first derivative of the Gaussian:
Once a "mother wavelet" is chosen, the continuous wavelet transform is carried out as a continuous, square-integrable function that can be scaled and translated. Let be the scaling constant and be the translation of the wavelet along the signal:
where is a continuous function in both the time domain and the frequency domain called the mother wavelet and represents the operation of complex conjug |
https://en.wikipedia.org/wiki/Peridinin-chlorophyll-protein%20complex | The peridinin-chlorophyll-protein complex (PCP or PerCP) is a soluble molecular complex consisting of the peridinin-chlorophyll a-protein bound to peridinin, chlorophyll, and lipids. The peridinin molecules absorb light in the blue-green wavelengths (470 to 550 nm) and transfer energy to the chlorophyll molecules with extremely high efficiency. PCP complexes are found in many photosynthetic dinoflagellates, in which they may be the primary light-harvesting complexes.
Structure
The PCP protein has been identified in dinoflagellate genomes in at least two forms, a homodimeric form composed of two 15-kD monomers, and a monomeric form of around 32kD believed to have evolved from the homodimeric form via gene duplication. The monomeric form consists of two pseudosymmetrical eight-helix domains in which the helices are packed in a complex topology resembling that of the beta sheets in a jelly roll fold. The three-dimensional arrangement of helices forms a boat-shaped molecule with a large central cavity in which the pigments and lipids are bound. Each eight-helix segment typically binds four peridinin molecules, one chlorophyll a molecule, and one lipid molecule such as digalactosyl diacyl glycerol; however, this stoichiometry varies among species and among PCP isoforms. The most common 4:1 peridinin:chlorophyll ratio was predicted by spectroscopy in the 1970s, but was unconfirmed until the crystal structure of the Amphidinium carterae PCP complex was solved in the 1990s. Whether formed from a protein monomer or dimer, the assembled protein-pigment complex is sometimes known as bPCP (for "building block") and is the minimal stable unit. In at least some PCP forms, including that from A. carterae, these building blocks assemble into a trimer thought to be the biologically functional state.
When the X-ray crystallography structure of PCP was solved in 1997, it represented a novel protein fold, and its topology remains unique among known proteins. The structure is referr |
https://en.wikipedia.org/wiki/Paleofauna%20of%20the%20Eocene%20Okanagan%20Highlands | The paleofauna of the Eocene Okanagan Highlands is comprised of Early Eocene arthropods, vertebrates, plus rare nematodes and molluscs found in geological formations of the northwestern North American Eocene Okanagan Highlands. The highlands lake bed series' as a whole are considered one of the great Canadian Lagerstätten. The paleofauna represents that of a late Ypresian upland temperate ecosystem immediately after the Paleocene-Eocene thermal maximum, and before the increased cooling of the middle and late Eocene to Oligocene. The fossiliferous deposits of the region were noted as early as 1873, with small amounts of systematic work happening in the 1880-90s on British Columbian sites, and 1920-30s for Washington sites. Focus and more detailed descriptive work on the Okanagan Highlands site started in the last 1970's. Most of the highlands sites are preserved as compression-impression fossils in "shales", but also includes a rare permineralized biota and an amber biota.
Extent
The series of lacustrine deposits are located across the Central British Columbia, Canada southeast to northern central Washington state, United States. grouped informally into "Northern", "Central", and "Southern" sites. The Northern sites consist of unnamed Ootsa Group formations which outcrop as the "Driftwood shales" near Smithers, British Columbia, the "Horsefly shales", of an unnamed formation and unnamed group which outcrop around Horsefly, British Columbia, and possibly sites now considered lost in the Quesnel, British Columbia area, The Central sites represent Kamloops Group formations with the McAbee Fossil Beds, Tranquille River site and Falkland site, all in the Tranquille Formation, the Quichena site and Stump Lake site in the Coldwater Beds and outcrops of the Chu Chua Formation near Barriere, British Columbia. The Southern sites include the Princeton Group Allenby Formation sites surrounding Princeton, British Columbia, such as "Nine Mile Creek", "One Mile Creek", "Plea |
https://en.wikipedia.org/wiki/Nextbio | NextBio is a privately owned software company that provides a platform for drug companies and life science researchers to search, discover, and share knowledge across public and proprietary data. It was co-founded by Saeid Akhtari, Ilya Kupershmidt, and Mostafa Ronaghi in 2004, and based in Cupertino, California, United States.
The NextBio Platform is an ontology-based semantic framework that connects highly heterogeneous data and textual information. The semantic framework is based on gene, tissue, disease, and compound ontologies. This framework contains information from different organisms, platforms, data types. and research areas that is integrated into and correlated within a single searchable environment using proprietary algorithms. It provides a unified interface for researchers to formulate and test new hypotheses across vast collections of experimental data.
According to the company, the enterprise version of the NextBio platform is being used in life science research and development and drug development by researchers and clinicians at: Merck Pharmaceutical, Johnson & Johnson Pharmaceutical Research & Development, L.L.C., Celgene, Genzyme, Eli Lilly and Company, and Regeneron Pharmaceuticals. This enterprise version allows internal, proprietary data to be uploaded and integrated into the NextBio database of publicly available data. According to the company, scientists are using NextBio to improve their ability to identify relevant prognostic and predictive molecular signatures which are significant in their research. In October 2013, Illumina acquired NextBio. |
https://en.wikipedia.org/wiki/HackBB | HackBB was a Tor hidden service Internet forum specializing in buying stolen credit cards, skimming ATMs, and hacking computers, servers and accounts. The site was often a destination for hacked and stolen data dumps. At some point the site was hosted by Tor hosting company Freedom Hosting.
The site was founded by 'OptimusCrime' in the earlier days of Tor. In June 2012, user 'Boneless' was promoted to an administrator role, who went on to handle site escrow. However, in March 2013 Boneless's account was used to destroy the site's database, and again in May by some accounts he secretly created. The site initially recovered from this, but shut down sometime afterwards due to the loss of faith in the site's administration and the raid on its host Freedom Hosting in August 2013. |
https://en.wikipedia.org/wiki/NCKIPSD | NCK-interacting protein with SH3 domain is a protein that in humans is encoded by the NCKIPSD gene.
The protein encoded by this gene is localized exclusively in the cell nucleus. It plays a role in signal transduction, and may function in the maintenance of sarcomeres and in the assembly of myofibrils into sarcomeres. It also plays an important role in stress fiber formation. The gene is involved in therapy-related leukemia by a chromosomal translocation t(3;11)(p21;q23) that involves this gene and the myeloid/lymphoid leukemia gene. Alternative splicing occurs in this locus and two transcript variants encoding distinct isoforms have been identified.
Interactions
NCKIPSD has been shown to interact with Grb2 and NCK1. |
https://en.wikipedia.org/wiki/International%20Principles%20on%20the%20Application%20of%20Human%20Rights%20to%20Communications%20Surveillance | The International Principles on the Application of Human Rights to Communications Surveillance (also called the "Necessary and Proportionate Principles" or just "the Principles") is a document which attempts to "clarify how international human rights law applies in the current digital environment".
Communications surveillance (that is to say, mass surveillance of communications) conflicts with a number of international human rights, mainly that of privacy. As a result, communications surveillance may only occur when prescribed by law necessary to achieve legitimate aim, and proportionate to the aim used.
The document consists of 13 principles developed to provide society groups, industry, governments, and others with a framework to assess whether current and proposed surveillance laws or statutes conflict with International Human Rights law.
History
The inception of the principles occurred as a result of a meeting between over 40 experts in privacy and security in Brussels, October 2012. After the initial consultation, a second meeting in Rio de Janeiro took place in December 2012 with the participation of the United Nations Special Rapporteur. Global consultation followed via conference calls every month between January and May 2013.
The drafting process, led by Access Now, EFF and Privacy International, along with several NGO's, Criminal Lawyers, Human rights advocates and privacy advocates were finalized and published for the first time on 10 July 2013 online at www.necessaryandproportionate.org.
In September 2013 at the 24th session of the UN Human Rights Council in Geneva, they were launched officially.
The principles have now been adopted globally by more than 400 organizations. The global adoption necessitated a number of primarily superficial textual changes in the language of the document for the purposes of translation. This occurred between March and May 2014.
The effect and intention of the principles remained the same, and the final and authorita |
https://en.wikipedia.org/wiki/Bulletin%20of%20the%20Atomic%20Scientists | The Bulletin of the Atomic Scientists is a nonprofit organization concerning science and global security issues resulting from accelerating technological advances that have negative consequences for humanity. The Bulletin publishes content at both a free-access website and a bi-monthly, nontechnical academic journal. The organization has been publishing continuously since 1945, when it was founded by Albert Einstein and former Manhattan Project scientists as the Bulletin of the Atomic Scientists of Chicago immediately following the atomic bombings of Hiroshima and Nagasaki. The organization is also the keeper of the symbolic Doomsday Clock, the time of which is announced each January.
Background
One of the driving forces behind the creation of the Bulletin was the amount of public interest surrounding atomic energy and rapid technological change at the dawn of the Atomic Age. In 1945 the public interest in atomic warfare and weaponry inspired contributors to the Bulletin to attempt to inform those interested about the dangers of the nuclear arms race they knew was coming and about the destruction that atomic war could bring about. To convey the particular peril posed by nuclear weapons, the Bulletin devised the Doomsday Clock in 1947, with an original setting of seven minutes to midnight.
The minute hand of the Clock first moved closer to midnight in response to changing world events in 1949, following the first Soviet nuclear test. The Clock has been set forward and back over the years as circumstances have changed; , it is set at 90 seconds to midnight. The Doomsday Clock is used to represent threats to humanity from a variety of sources: nuclear and other weapons of mass destruction, climate change, and disruptive technologies.
In 2015, the Bulletin unveiled its Doomsday Dashboard, an interactive infographic that illustrates some of the data the Bulletin Science and Security Board takes into account when deciding the time of the Clock each year. As of August |
https://en.wikipedia.org/wiki/Euclidean%20distance | In mathematics, the Euclidean distance between two points in Euclidean space is the length of a line segment between the two points.
It can be calculated from the Cartesian coordinates of the points using the Pythagorean theorem, therefore occasionally being called the Pythagorean distance. These names come from the ancient Greek mathematicians Euclid and Pythagoras, although Euclid did not represent distances as numbers, and the connection from the Pythagorean theorem to distance calculation was not made until the 18th century.
The distance between two objects that are not points is usually defined to be the smallest distance among pairs of points from the two objects. Formulas are known for computing distances between different types of objects, such as the distance from a point to a line. In advanced mathematics, the concept of distance has been generalized to abstract metric spaces, and other distances than Euclidean have been studied. In some applications in statistics and optimization, the square of the Euclidean distance is used instead of the distance itself.
Distance formulas
One dimension
The distance between any two points on the real line is the absolute value of the numerical difference of their coordinates, their absolute difference. Thus if and are two points on the real line, then the distance between them is given by:
A more complicated formula, giving the same value, but generalizing more readily to higher dimensions, is:
In this formula, squaring and then taking the square root leaves any positive number unchanged, but replaces any negative number by its absolute value.
Two dimensions
In the Euclidean plane, let point have Cartesian coordinates and let point have coordinates . Then the distance between and is given by:
This can be seen by applying the Pythagorean theorem to a right triangle with horizontal and vertical sides, having the line segment from to as its hypotenuse. The two squared formulas inside the square root give t |
https://en.wikipedia.org/wiki/Ethyl%20maltol | Ethyl maltol is an organic compound that is a common flavourant in some confectioneries. It is related to the more common flavorant maltol by replacement of the methyl group by an ethyl group. It is a white solid with a sweet smell that can be described as caramelized sugar or as caramelized fruit.
The conjugate base derived from ethylmaltol, again like maltol, has a high affinity for iron, forming a red coordination complex. In such compounds, the heterocycle is a bidentate ligand.
Original patent: |
https://en.wikipedia.org/wiki/F-test | An F-test is any statistical test in which the test statistic has an F-distribution under the null hypothesis. It is most often used when comparing statistical models that have been fitted to a data set, in order to identify the model that best fits the population from which the data were sampled. Exact "F-tests" mainly arise when the models have been fitted to the data using least squares. The name was coined by George W. Snedecor, in honour of Ronald Fisher. Fisher initially developed the statistic as the variance ratio in the 1920s.
Common examples
Common examples of the use of F-tests include the study of the following cases:
The hypothesis that the means of a given set of normally distributed populations, all having the same standard deviation, are equal. This is perhaps the best-known F-test, and plays an important role in the analysis of variance (ANOVA).
The hypothesis that a proposed regression model fits the data well. See Lack-of-fit sum of squares.
The hypothesis that a data set in a regression analysis follows the simpler of two proposed linear models that are nested within each other.
In addition, some statistical procedures, such as Scheffé's method for multiple comparisons adjustment in linear models, also use F-tests.
F-test of the equality of two variances
The F-test is sensitive to non-normality. In the analysis of variance (ANOVA), alternative tests include Levene's test, Bartlett's test, and the Brown–Forsythe test. However, when any of these tests are conducted to test the underlying assumption of homoscedasticity (i.e. homogeneity of variance), as a preliminary step to testing for mean effects, there is an increase in the experiment-wise Type I error rate.
Formula and calculation
Most F-tests arise by considering a decomposition of the variability in a collection of data in terms of sums of squares. The test statistic in an F-test is the ratio of two scaled sums of squares reflecting different sources of variability. These sums of s |
https://en.wikipedia.org/wiki/Buyer%20decision%20process | As part of consumer behavior, the buying decision process is the decision-making process used by consumers regarding the market transactions before, during, and after the purchase of a good or service. It can be seen as a particular form of a cost–benefit analysis in the presence of multiple alternatives.
Common examples include shopping and deciding what to eat. Decision-making is a psychological construct. This means that although a decision cannot be "seen", we can infer from observable behavior that a decision has been made. Therefore, we conclude that a psychological "decision-making" event has occurred. It is a construction that imputes a commitment to action. That is, based on observable actions, we assume that people have made a commitment to effect the action.
Nobel laureate Herbert A. Simon sees economic decision-making as a vain attempt to be rational. Simon claimed (in 1947 and 1957) that if a complete analysis is to be done, a decision will be immensely complex. Simon also wrote that peoples' information processing ability is limited. The assumption of a perfectly rational economic actor is unrealistic. Consumers are influenced by emotional and nonrational considerations making attempts to be rational only partially successful. He called for replacing the perfect rationality assumptions of homo economicus with a conception of rationality tailored to cognitively limited agents. Even if the buyer decision process was highly rational, the required product information and/or knowledge is often substantially limited in quality or extent, as is the availability of potential alternatives. Factors such as cognitive effort and decision-making time also play a role.
Stages
The five stages of a decision process were first introduced by philosopher John Dewey in How We Think in 1910. Later studies expanded upon Dewey's initial work and are seen as foundational for analysis of consumer purchasing decision-making. Dewey did not refer in How We Think specifically |
https://en.wikipedia.org/wiki/Frans%20Oort | Frans Oort (born 17 July 1935) is a Dutch mathematician who specializes in algebraic geometry.
Career
Oort studied from 1952 to 1958 at Leiden University, where he graduated with a thesis on elliptic curves. He received his doctorate in 1961 in Leiden from and Jaap Murre with thesis Reducible and Multiple Algebraic Curves, but had previously studied under Jean-Pierre Serre in Paris and Aldo Andreotti in Pisa. Oort was from 1961 at the University of Amsterdam, where he became a professor in 1967. In 1977, until his retirement in 2000, he was a professor at Utrecht University.
He was a visiting scholar at several academic institutions, including Harvard University (1966/67) and Aarhus University (1972/73). In 2008 he was the Eilenberg Professor at Columbia University.
His doctoral students include Bas Edixhoven, Michiel Hazewinkel, Aise Johan de Jong, Hendrik Lenstra and Joseph Steenbrink.
Research
Oort's research deals with, among other topics, abelian varieties and their modules. In 1994, he formulated what is now known as the André–Oort conjecture (generalizing a conjecture made in 1989 by Yves André). In 2000 Oort proved a conjecture made by Grothendieck in 1970.
Awards and honors
In 1962, Oort made a short contribution Multiple algebraic curves at the International Congress of Mathematicians in Stockholm, but was not an invited speaker. In 2011 he was elected a member of Academia Europaea. In July 2013, he gave a talk at the International Congress of Chinese Mathematicians in Taipei.
Personal life
Oort married and later divorced author (1936–2020).
Selected publications
Commutative group schemes, Springer 1966;
as editor: Algebraic Geometry, Oslo 1970, Wolters-Noordhoff 1972
with Ke-Zheng Li: Moduli of supersingular abelian varieties, Springer 1998
as editor with Steenbrink and van der Geer: Arithmetic algebraic geometry , Birkhäuser 1991;
as editor with Carel Faber and Gerard van der Geer: Moduli of abelian varieties, Birkhäuser 2001
with Chi |
https://en.wikipedia.org/wiki/Work%20%28thermodynamics%29 | Thermodynamic work is one of the principal processes by which a thermodynamic system can interact with its surroundings and exchange energy. This exchange results in externally measurable macroscopic forces on the system's surroundings, which can cause mechanical work, to lift a weight, for example, or cause changes in electromagnetic, or gravitational variables. The surroundings also can perform work on a thermodynamic system, which is measured by an opposite sign convention.
For thermodynamic work, appropriately chosen externally measured quantities are exactly matched by values of or contributions to changes in macroscopic internal state variables of the system, which always occur in conjugate pairs, for example pressure and volume or magnetic flux density and magnetization.
In the International System of Units (SI), work is measured in joules (symbol J). The rate at which work is performed is power, measured in joules per second, and denoted with the unit watt (W).
History
1824
Work, i.e. "weight lifted through a height", was originally defined in 1824 by Sadi Carnot in his famous paper Reflections on the Motive Power of Fire, where he used the term motive power for work. Specifically, according to Carnot:
We use here motive power to express the useful effect that a motor is capable of producing. This effect can always be likened to the elevation of a weight to a certain height. It has, as we know, as a measure, the product of the weight multiplied by the height to which it is raised.
1845
In 1845, the English physicist James Joule wrote a paper On the mechanical equivalent of heat for the British Association meeting in Cambridge. In this paper, he reported his best-known experiment, in which the mechanical power released through the action of a "weight falling through a height" was used to turn a paddle-wheel in an insulated barrel of water.
In this experiment, the motion of the paddle wheel, through agitation and friction, heated the body of water, s |
https://en.wikipedia.org/wiki/Toy%20forts%20and%20castles | A toy fort is a miniature fortress or castle that is used as a setting to stage battles using toy soldiers. Toy forts come in many shapes and sizes; some are copies of existing historical structures, while others are imagined with specific elements to enable realistic play, such as moats, drawbridges, and battlements. Toy fort designs range from the châteaux of Europe to the stockade forts of the American wild west.
History
Toy forts and castles first appeared at the beginning of the nineteenth century in Germany, a country that dominated the world of toy manufacturing up until WW1. The earliest examples came as a set of generic wooden blocks which could be configured in many different ways. As time went on, some of these sets were designed to portray specific structures associated with real battles.
Around 1850 dollhouse manufacturers started to apply their production methods and capabilities towards the production of toy forts and castles. Sets would consist of wooden components, some blocks and some flat, painted to depict details such as stone, brick, windows, arches and vegetation. The parts would be shipped in a box which was designed to be inverted and then used as the base for the toy fort. This design became the standard design for toy forts and castles for the next 100 years.
The Germans dominated the toy fort market until about 1900 when other manufacturers from France, Denmark, Britain, and the USA started to appear on the scene. As technology progressed, new materials were used in the manufacturing of toy forts including tin, zinc alloy, composition, cardboard, hardboard, MDF, and finally plastics.
Manufacturers
The three best-known manufacturers of toy forts were Moritz Gottschalk (Germany), O. and M. Hausser (Germany), and Lines Bros. (Great Britain).
Germany
Christian Hacker
Moritz Gottschalk (1840—1905) started his career as a bookbinder, but by the age of 25 had branched off into children's toys which would eventually lead to him becoming |
https://en.wikipedia.org/wiki/Hilbert%20metric | In mathematics, the Hilbert metric, also known as the Hilbert projective metric, is an explicitly defined distance function on a bounded convex subset of the n-dimensional Euclidean space Rn. It was introduced by as a generalization of Cayley's formula for the distance in the Cayley–Klein model of hyperbolic geometry, where the convex set is the n-dimensional open unit ball. Hilbert's metric has been applied to Perron–Frobenius theory and to constructing Gromov hyperbolic spaces.
Definition
Let Ω be a convex open domain in a Euclidean space that does not contain a line. Given two distinct points A and B of Ω, let X and Y be the points at which the straight line AB intersects the boundary of Ω, where the order of the points is X, A, B, Y. Then the Hilbert distance d(A, B) is the logarithm of the cross-ratio of this quadruple of points:
The function d is extended to all pairs of points by letting d(A, A) = 0 and defines a metric on Ω. If one of the points A and B lies on the boundary of Ω then d can be formally defined to be +∞, corresponding to a limiting case of the above formula
when one of the denominators is zero.
A variant of this construction arises for a closed convex cone K in a Banach space V (possibly, infinite-dimensional). In addition, the cone K is assumed to be pointed, i.e. K ∩ (−K) = {0} and thus K determines a partial order on V. Given any vectors v and w in K \ {0}, one first defines
The Hilbert pseudometric on K \ {0} is then defined by the formula
It is invariant under the rescaling of v and w by positive constants and so descends to a metric on the space of rays of K, which is interpreted as the projectivization of K (in order for d to be finite, one needs to restrict to the interior of K). Moreover, if K ⊂ R × V is the cone over a convex set Ω,
then the space of rays of K is canonically isomorphic to Ω. If v and w are vectors in rays in K corresponding to the points A, B ∈ Ω then these two formulas for d yield the same va |
https://en.wikipedia.org/wiki/Validity%20%28logic%29 | In logic, specifically in deductive reasoning, an argument is valid if and only if it takes a form that makes it impossible for the premises to be true and the conclusion nevertheless to be false. It is not required for a valid argument to have premises that are actually true, but to have premises that, if they were true, would guarantee the truth of the argument's conclusion. Valid arguments must be clearly expressed by means of sentences called well-formed formulas (also called wffs or simply formulas).
The validity of an argument can be tested, proved or disproved, and depends on its logical form.
Arguments
In logic, an argument is a set of statements expressing the premises (whatever consists of empirical evidences and axiomatic truths) and an evidence-based conclusion.
An argument is valid if and only if it would be contradictory for the conclusion to be false if all of the premises are true. Validity does not require the truth of the premises, instead it merely necessitates that conclusion follows from the formers without violating the correctness of the logical form. If also the premises of a valid argument are proven true, this is said to be sound.
The corresponding conditional of a valid argument is a logical truth and the negation of its corresponding conditional is a contradiction. The conclusion is a logical consequence of its premises.
An argument that is not valid is said to be "invalid".
An example of a valid (and sound) argument is given by the following well-known syllogism:
All men are mortal. (True)
Socrates is a man. (True)
Therefore, Socrates is mortal. (True)
What makes this a valid argument is not that it has true premises and a true conclusion, but the logical necessity of the conclusion, given the two premises. The argument would be just as valid were the premises and conclusion false. The following argument is of the same logical form but with false premises and a false conclusion, and it is equally valid:
All cups are gre |
https://en.wikipedia.org/wiki/A%20Primer%20of%20Real%20Functions | A Primer of Real Functions is a revised edition of a classic Carus Monograph on the theory of functions of a real variable. It is authored by R. P. Boas, Jr and updated by his son Harold P. Boas. |
https://en.wikipedia.org/wiki/Mary%20Louisa%20White | Mary Louisa White (2 September 1866 – January 1935) was a British composer, pianist, and educator who invented a Letterless Method of musical notation. Her parents were Robert and Louisa Makin White. Mary Louisa, known to her family as "Louie," was the oldest of their four children. She also had a half brother and a half sister from her father's first marriage.
White studied music with John Farmer in London, and gave frequent concerts in London and Paris, including at the Steinway Hall in London. She taught piano at Kensington High School at the turn of the 20th century, and worked at the Girls' Day School Trust with her sisters Jessie and Winnie from 1902 to 1903. At the time, Kensington High School was administered by the Girls' Day School Trust.
White invented the "Letterless Method" of teaching music to beginners. The Letterless Method used metal clefs, rings, disks, and black and white buttons for notes, which children could manipulate for tactile learning.
White's papers, including scrapbooks about her musical career created by her mother and sisters, are archived at University College, London. Her compositions were published by Joseph Williams and Alfred Novello, both of London.
White's compositions include:
Operetta
Babes in the Woods, opus 42
Beauty and the Beast, opus 41
Orchestra
Transvaal War Symphony
Piano
Ballade in G flat
Dances No 1 and 2, Opus 47
Impromptu in E flat, Opus 54 No 2
Minuet in A flat
Nocturne in D flat
Novelette in c minor, Opus 36 No 2
Prelude in D flat
Rhapsody in b flat minor
Short Lyrics
Sketch Book (Gavotte, Hunting Song, March, Minuet, Pastorale, Waltz)
Spinning Wheel
Tiny Tunes for Young Musicians
Two Waltzes
Without Octaves
Vocal
Hush-a-bye
Jubilate (trio for treble voices)
Maypole
Night's Rhapsody (duet)
Prelude of Spring
School Song for Girls
Secret of the Sea
Sleep, Little Baby, Sleep
Sleep, Sweetly Sleep
Song of the Water Sprite
There be None of Beauty's Daughters
To the River
Twelve Easy Duets
When First I S |
https://en.wikipedia.org/wiki/Dog%20intelligence | Dog intelligence or dog cognition is the process in dogs of acquiring information and conceptual skills, and storing them in memory, retrieving, combining and comparing them, and using them in new situations.
Studies have shown that dogs display many behaviors associated with intelligence. They have advanced memory skills, and are able to read and react appropriately to human body language such as gesturing and pointing, and to understand human voice commands. Dogs demonstrate a theory of mind by engaging in deception.
Evolutionary perspective
Dogs have often been used in studies of cognition, including research on perception, awareness, memory, and learning, notably research on classical and operant conditioning. In the course of this research, behavioral scientists uncovered a surprising set of social-cognitive abilities in the domestic dog, abilities that are neither possessed by dogs' closest canine relatives nor by other highly intelligent mammals such as great apes. Rather, these skills resemble some of the social-cognitive skills of human children. This may be an example of convergent evolution, which happens when distantly related species independently evolve similar solutions to the same problems. For example, fish, penguins and dolphins have each separately evolved flippers as solution to the problem of moving through the water. With dogs and humans, we may see psychological convergence; that is, dogs have evolved to be cognitively more similar to humans than we are to our closest genetic relatives.
However, it is questionable whether the cognitive evolution of humans and animals may be called "independent". The cognitive capacities of dogs have inevitably been shaped by millennia of contact with humans. As a result of this physical and social evolution, many dogs readily respond to social cues common to humans, quickly learn the meaning of words, show cognitive bias and exhibit emotions that seem to reflect those of humans.
Research suggests that dom |
https://en.wikipedia.org/wiki/Kiesselbach%27s%20plexus | Kiesselbach's plexus is an anastomotic arterial network (plexus) of four or five arteries in the nose supplying the nasal septum. It lies in the anterior inferior part of the septum known as Little's area, Kiesselbach's area, or Kiesselbach's triangle. It is a common site for nosebleeds.
Structure
Kiesselbach's plexus is an anastomosis of four or five arteries:
the anterior ethmoidal artery, a branch of the ophthalmic artery.
the sphenopalatine artery, a terminal branch of the maxillary artery.
the greater palatine artery, a branch of the maxillary artery.
a septal branch of the superior labial artery, a branch of the facial artery.
a posterior ethmoidal artery, a branch of the ophthalmic artery. There is contention as whether this is truly part of Kiesselbach's plexus. Most sources quote that it is not part of the plexus, but rather one of the blood supplies for the nasal septum itself.
It runs vertically downwards just behind the columella, and crosses the floor of the nose. It joins the venous plexus on the lateral nasal wall.
Function
Kiesselbach's plexus supplies blood to the nasal septum.
Clinical significance
Ninety percent of nosebleeds (epistaxis) occur in Kiesselbach's plexus. It is exposed to the drying effect of inhaled air. It can also be damaged by trauma from a finger nail (nose picking), as it is fragile. It is the usual site for nosebleeds in children and young adults. A physician may use a nasal speculum to see that an anterior nosebleed comes from Kiesselbach's plexus.
History
James Lawrence Little (1836–1885), an American surgeon, first described the area in detail in 1879. Little described the area as being "about half an inch ... from the lower edge of the middle of the column [septum]".
Kiesselbach's plexus is named after Wilhelm Kiesselbach (1839–1902), a German otolaryngologist who published a paper on the area in 1884. The area may be called Little's area, Kiesselbach's area, or Kiesselbach's triangle.
See also
Anatomical |
https://en.wikipedia.org/wiki/Flag%20of%20the%20Black%20Country | The Black Country flag is the flag of the Black Country region of England. It was registered with the Flag Institute as a regional flag in 2012.
History
The design was the winner of a competition run by the Black Country Living Museum in response to a campaign by the Parliamentary Flags & Heraldry Committee encouraging communities and regions to develop their own flags to celebrate the Diamond Jubilee of Elizabeth II and the 2012 Summer Olympics.
After 1,500 votes were cast by members of the public, a design by 11-year old Gracie Sheppard of Redhill School, Stourbridge was announced as the winning entry at the museum's Festival of Steam, celebrating 300 years of the Newcomen atmospheric engine.
The flag was flown at Eland House, the headquarters of the Department for Communities and Local Government on 14 July 2013 to celebrate 'Black Country Day' and also Britain's role in leading the Industrial Revolution.
Design
The flag features a chain to represent the manufacturing heritage of the area whilst the upright triangular shape in the background recalls the iconic glass cones and iron furnaces that featured in the architectural landscape of the area. The red and black colours recall the famous description of the Black Country by Elihu Burritt that it was "black by day and red by night" owing to the smoke and fires of industry.
The Pantone colours for the flag are:
Black
White
Red 186 C
Flying the flag
The flag is one of very few regional, non-historic county flags that may be flown without consent of a local planning authority, providing the flag is "maintained in a condition that does not impair the overall visual appearance of the site" and does not block official signs (such as road signs).
Controversy
In July 2015, Wolverhampton-born historian and anti-racism campaigner Patrick Vernon OBE called for the design of the flag to be replaced, saying that "the Black Country factories and foundries made chains, shackles and manacles during slavery tha |
https://en.wikipedia.org/wiki/Maintenance%20release | A maintenance release (also minor release or Maintenance Pack or MP) is a release of a product that does not add new features or content. For instance, in computer software, maintenance releases are typically intended to solve minor problems, typically "bugs" or security issues.
Example of minor version numbering
The somewhat unusual version number "3.0.5a" was used for a minor release of KDE because of a lack of version numbers. Work on KDE 3.1 had already started and, up to that day, the release coordinator used version numbers such as 3.0.5, 3.0.6 internally in the main CVS repository to mark snapshots of the upcoming 3.1. Then after 3.0.3, a number of important and unexpected bug fixes (starting from 3.0.4) suddenly became necessary, leading to a conflict, because 3.0.5 was at this time already in use. More recent KDE release cycles have tagged pre-release snapshots with large revision numbers, such as 3.1.95, to avoid such conflicts.
See also
Patch (computing)
Software versioning
Software release life cycle
Point release
Software release |
https://en.wikipedia.org/wiki/Categorical%20logic |
Categorical logic is the branch of mathematics in which tools and concepts from category theory are applied to the study of mathematical logic. It is also notable for its connections to theoretical computer science.
In broad terms, categorical logic represents both syntax and semantics by a category, and an interpretation by a functor. The categorical framework provides a rich conceptual background for logical and type-theoretic constructions. The subject has been recognisable in these terms since around 1970.
Overview
There are three important themes in the categorical approach to logic:
Categorical semantics Categorical logic introduces the notion of structure valued in a category C with the classical model theoretic notion of a structure appearing in the particular case where C is the category of sets and functions. This notion has proven useful when the set-theoretic notion of a model lacks generality and/or is inconvenient. R.A.G. Seely's modeling of various impredicative theories, such as System F, is an example of the usefulness of categorical semantics.
It was found that the connectives of pre-categorical logic were more clearly understood using the concept of adjoint functor, and that the quantifiers were also best understood using adjoint functors.
Internal languages This can be seen as a formalization and generalization of proof by diagram chasing. One defines a suitable internal language naming relevant constituents of a category, and then applies categorical semantics to turn assertions in a logic over the internal language into corresponding categorical statements. This has been most successful in the theory of toposes, where the internal language of a topos together with the semantics of intuitionistic higher-order logic in a topos enables one to reason about the objects and morphisms of a topos "as if they were sets and functions". This has been successful in dealing with toposes that have "sets" with properties incompatible with classical lo |
https://en.wikipedia.org/wiki/Digraphia | In sociolinguistics, digraphia refers to the use of more than one writing system for the same language. Synchronic digraphia is the coexistence of two or more writing systems for the same language, while diachronic digraphia (or sequential digraphia) is the replacement of one writing system by another for a particular language.
Hindustani, with an Urdu literary standard written in Urdu alphabet and a High Hindi standard written in Devanagari, is one of the 'textbook examples' of synchronic digraphia, cases where writing systems are used contemporaneously. An example of diachronic digraphia, where one writing system replaces another, occurs in the case of Turkish, for which the traditional Arabic writing system was replaced with a Latin-based system in 1928.
Digraphia has implications in language planning, language policy, and language ideology.
Terminology
Etymology
English digraphia, like French digraphie, etymologically derives from Greek di- δι- "twice" and -graphia -γραφία "writing".
Digraphia was modeled upon diglossia "the coexistence of two languages or dialects among a certain population", which derives from Greek diglossos δίγλωσσος "bilingual." Charles A. Ferguson, a founder of sociolinguistics, coined diglossia in 1959. Grivelet analyzes how the influence of diglossia on the unrelated notion of digraphia has "introduced some distortion in the process of defining digraphia," such as distinguishing "high" and "low" varieties. Peter Unseth notes one usage of "digraphia" that most closely parallels Ferguson's "diglossia," situations where a language uses different scripts for different domains; for instance, "shorthand in English, pinyin in Chinese for alphabetizing library files, etc. or several scripts which are replaced by Latin script during e-mail usage."
History
The Oxford English Dictionary, which does not yet include digraphia, enters two terms, digraph and digraphic. First, the linguistic term digraph is defined as, "A group of two letters ex |
https://en.wikipedia.org/wiki/Yap%20%28company%29 | Yap Speech Cloud was a multimodal speech recognition system developed by American technology company Yap Inc. It offered a fully cloud-based speech-to-text transcription platform that was used by customers such as Microsoft.
The Company was a contestant at the inaugural TechCrunch conference and was subsequently acquired by Amazon in September 2011 to help develop products such as Alexa Voice Service, Echo, and Fire TV.
See also
List of speech recognition software |
https://en.wikipedia.org/wiki/Conditional%20random%20field | Conditional random fields (CRFs) are a class of statistical modeling methods often applied in pattern recognition and machine learning and used for structured prediction. Whereas a classifier predicts a label for a single sample without considering "neighbouring" samples, a CRF can take context into account. To do so, the predictions are modelled as a graphical model, which represents the presence of dependencies between the predictions. What kind of graph is used depends on the application. For example, in natural language processing, "linear chain" CRFs are popular, for which each prediction is dependent only on its immediate neighbours. In image processing, the graph typically connects locations to nearby and/or similar locations to enforce that they receive similar predictions.
Other examples where CRFs are used are: labeling or parsing of sequential data for natural language processing or biological sequences, part-of-speech tagging, shallow parsing, named entity recognition, gene finding, peptide critical functional region finding, and object recognition and image segmentation in computer vision.
Description
CRFs are a type of discriminative undirected probabilistic graphical model.
Lafferty, McCallum and Pereira define a CRF on observations and random variables as follows:
Let be a graph such that , so that is indexed by the vertices of .
Then is a conditional random field when each random variable , conditioned on , obeys the Markov property with respect to the graph; that is, its probability is dependent only on its neighbours in G:
, where means
that and are neighbors in .
What this means is that a CRF is an undirected graphical model whose nodes can be divided into exactly two disjoint sets and , the observed and output variables, respectively; the conditional distribution is then modeled.
Inference
For general graphs, the problem of exact inference in CRFs is intractable. The inference problem for a CRF is basically the same as for an MR |
https://en.wikipedia.org/wiki/Luna%27s%20slice%20theorem | In mathematics, Luna's slice theorem, introduced by , describes the local behavior of an action of a reductive algebraic group on an affine variety. It is an analogue in algebraic geometry of the theorem that a compact Lie group acting on a smooth manifold X has a slice at each point x, in other words a subvariety W such that X looks locally like G×Gx W. (see slice theorem (differential geometry).) |
https://en.wikipedia.org/wiki/Pesticide%20drift | Pesticide drift refers to the unintentional diffusion of pesticides and the potential negative effects of pesticide application, including off-target contamination due to spray drift as well as runoff from plants or soil. This can lead to damage in human health, environmental contamination, and property damage. Some pesticides are more likely to drift than others which can mean it is more harmful in some cases. For example, fumigants which are gaseous pesticides move easily through air and will drift if not contained. Some pesticides look like a cloud when they drift while others can be invisible and odorless.
Types
With placement (localised) spraying of broad spectrum pesticides, wind drift must be minimised, and considerable efforts have been made to quantify and control spray drift from hydraulic nozzles. Conversely, wind drift is also an efficient mechanism for moving droplets of an appropriate size range to their targets over a wide area with ultra-low volume (ULV) spraying.
Himel (1974) made a distinction between exo-drift (the transfer of spray out of the target area) and endo-drift, where the active ingredient (AI) in droplets falls into the target area, but does not reach the biological target. Endo-drift is volumetrically more significant and may therefore cause greater ecological contamination (e.g. where chemical pesticides pollute ground water).
Bystander exposure describes the event when individuals unintentionally come in contact with airborne pesticides. Bystanders include workers working in an area separate to the pesticide application area, individuals living in the surrounding areas of an application area, or individuals passing by fields as they are being treated with a pesticide.
Herbicide volatilisation
Herbicide volatilisation refers to evaporation or sublimation of a volatile herbicide. The effect of a gaseous chemical is lost at its intended place of application and may move downwind and affect other plants not intended to be affected ca |
https://en.wikipedia.org/wiki/Essential%20systems%20analysis | Essential systems analysis was a new methodology for software specification published in 1984 by Stephen M. McMenamin and John F. Palmer for performing structured systems analysis based on the concept of event partitioning.
The essence of a system is "its required behavior independent of the technology used to implement the system". It is an abstract model of what the system must do without describing how it will do it.
The methodology proposed that finding the true requirements for an information system entails the development of an essential model for the system, based on the concepts of a perfect internal technology, composed of:
a perfect memory, that is infinitely fast and big, and
a perfect processor, that is infinitely potent and fast.
Edward Yourdon later adapted it to develop modern structured analysis.
The main result was a new and more systematic way to develop the data-flow diagrams, which are the most characteristic tool of structured analysis.
Essential analysis, as adopted in Yourdon's modern structured analysis, was the main software development methodology until object-oriented analysis became mainstream. |
https://en.wikipedia.org/wiki/Limit%20comparison%20test | In mathematics, the limit comparison test (LCT) (in contrast with the related direct comparison test) is a method of testing for the convergence of an infinite series.
Statement
Suppose that we have two series and with for all .
Then if with , then either both series converge or both series diverge.
Proof
Because we know that for every there is a positive integer such that for all we have that , or equivalently
As we can choose to be sufficiently small such that is positive.
So and by the direct comparison test, if converges then so does .
Similarly , so if diverges, again by the direct comparison test, so does .
That is, both series converge or both series diverge.
Example
We want to determine if the series converges. For this we compare it with the convergent series
As we have that the original series also converges.
One-sided version
One can state a one-sided comparison test by using limit superior. Let for all . Then if with and converges, necessarily converges.
Example
Let and for all natural numbers . Now
does not exist, so we cannot apply the standard comparison test. However,
and since converges, the one-sided comparison test implies that converges.
Converse of the one-sided comparison test
Let for all . If diverges and converges, then necessarily
, that is,
. The essential content here is that in some sense the numbers are larger than the numbers .
Example
Let be analytic in the unit disc and have image of finite area. By Parseval's formula the area of the image of is proportional to . Moreover,
diverges. Therefore, by the converse of the comparison test, we have
, that is,
.
See also
Convergence tests
Direct comparison test |
https://en.wikipedia.org/wiki/AIDS%20Research%20and%20Human%20Retroviruses | AIDS Research and Human Retroviruses is a peer-reviewed scientific journal focusing on HIV/AIDS research, as well as on human retroviruses and their related diseases. The journal was founded in 1983 as AIDS Research, and acquired its current name in 1987. It is published by Mary Ann Liebert, and edited by R. Keith Reeves and Lish Ndhlovu.
It is the official journal of the International Retrovirology Association.
Indexing and abstracting
AIDS Research and Human Retroviruses is indexed and abstracted in the following databases:
External links
AIDS Research and Human Retroviruses website
International Retrovirology Association website
Academic journals established in 1983
Immunology journals
Mary Ann Liebert academic journals
English-language journals
HIV/AIDS journals
Academic journals associated with learned and professional societies |
https://en.wikipedia.org/wiki/Timeline%20of%20quantum%20computing%20and%20communication | This is a timeline of quantum computing.
1960s
1968
Stephen Wiesner invented conjugate coding (published in ACM SIGACT News 15(1):78–88).
1970s
1970
James Park articulated the no-cloning theorem.
1973
Alexander Holevo published a paper showing that n qubits can carry more than n classical bits of information, but at most n classical bits are accessible (a result known as "Holevo's theorem" or "Holevo's bound").
Charles H. Bennett showed that computation can be done reversibly.
1975
R. P. Poplavskii published "Thermodynamical models of information processing" (in Russian) which showed the computational infeasibility of simulating quantum systems on classical computers, due to the superposition principle.
1976
Polish mathematical physicist Roman Stanisław Ingarden published the paper "Quantum Information Theory" in Reports on Mathematical Physics, vol. 10, 43–72, 1976 (The paper was submitted in 1975). It is one of the first attempts at creating a quantum information theory, showing that Shannon information theory cannot directly be generalized to the quantum case, but rather that it is possible to construct a quantum information theory, which is a generalization of Shannon's theory, within the formalism of a generalized quantum mechanics of open systems and a generalized concept of observables (the so-called semi-observables).
1980s
1980
Paul Benioff described the first quantum mechanical model of a computer. In this work, Benioff showed that a computer could operate under the laws of quantum mechanics by describing a Schrödinger equation description of Turing machines, laying a foundation for further work in quantum computing. The paper was submitted in June 1979 and published in April 1980.
Yuri Manin briefly motivated the idea of quantum computing.
Tommaso Toffoli introduced the reversible Toffoli gate, which (together with initialized ancilla bits) is functionally complete for reversible classical computation.
1981
At the First Conference on |
https://en.wikipedia.org/wiki/Chairman%20Mao%20badge | Chairman Mao badge () is the name given to a type of pin badge displaying an image of Mao Zedong that was ubiquitous in the People's Republic of China during the active phase of the Cultural Revolution, from 1966 to 1971. The term is also used for badges associated with Mao that do not actually have a picture of him on them. It is estimated that several billion Chairman Mao badges were produced during the period of the Cultural Revolution.
History
Badges depicting Mao Zedong first appeared at the Chinese People's Anti-Japanese Military and Political College () at Yan'an during the 1930s. These early badges were homemade, usually being constructed out of the metal from used toothpaste tubes.
By the 1940s badges showing Mao by himself or together with other important people were being produced in small numbers as commemorative medals or as awards for service to the Chinese Communist Party or to the army. Unlike the later Cultural Revolution period badges, which normally portrayed Mao by himself, these badges frequently portrayed Mao side by side with other Chinese revolutionary figures such as Zhu De, Chen Yi, He Long, Lin Biao and Lu Xun, or showed Mao with communist leaders from other countries, such as Stalin and Kim Il Sung. During this period badges were smaller but more robust than the Cultural Revolution period badges, and some badges produced during the 1950s were even made of gold (initially 22 carat, but later reduced to 13 or 14 carat).
After the establishment of the People's Republic of China in 1949, and throughout the 1950s and early 1960s, badges showing an image of Mao were produced mainly for special occasions, for example Chinese soldiers were given star-shaped badges with a portrait of Mao when they returned to China from the Korean War, and labourers working on the Sichuan-Tibet Highway were given gold-plated copper badges with a bilingual inscription in Chinese and Tibetan on completion of the road in December 1954. By the mid-1960s Mao badge |
https://en.wikipedia.org/wiki/CyTOF | Cytometry by time of flight, or CyTOF, is an application of mass cytometry used to quantify labeled targets on the surface and interior of single cells. CyTOF allows the quantification of multiple cellular components simultaneously using an ICP-MS detector.
CyTOF takes advantage of immunolabeling to quantify proteins, carbohydrates or lipids in a cell. Targets are selected to answer a specific research question and are labeled with lanthanide metal tagged antibodies. Labeled cells are nebulized and mixed with heated argon gas to dry the cell containing particles. The sample-gas mixture is focused and ignited with an argon plasma torch. This breaks the cells into their individual atoms and creates an ion cloud. Abundant low weight ions generated from environmental air and biological molecules are removed using a quadrupole mass analyzer. The remaining heavy ions from the antibody tags are quantified by Time-of-flight mass spectrometry. Ion abundances correlate with the amount of target per cell and can be used to infer cellular qualities.
Mass spectrometry's sensitivity to detect different ions allows measurements of upwards of 50 targets per cell while avoiding issues with spectral overlap seen when using fluorescent probes. However, this sensitivity also means trace heavy metal contamination is a concern. Using large numbers of probes creates new problems in analyzing the high dimensional data generated.
History
In 1994 Tsutomu Nomizu and colleagues at Nagoya University performed the first mass spectrometry experiments of single cells. Nomizu realized that single cells could be nebulized, dried, and ignited in plasma to generate clouds of ions which could be detected by emission spectrometry. In this type of experiment elements such as calcium within the cell could be quantified. Inspired by Flow cytometry, in 2007 Scott D. Tanner built upon this ICP-MS with the first multiplexed assay using lanthanide metals to label DNA and cell surface markers. In 2008 Tann |
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