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https://en.wikipedia.org/wiki/Cofibration
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In mathematics, in particular homotopy theory, a continuous mapping between topological spaces
,
is a cofibration if it has the homotopy extension property with respect to all topological spaces . That is, is a cofibration if for each topological space , and for any continuous maps and with , for any homotopy from to , there is a continuous map and a homotopy from to such that for all and . (Here, denotes the unit interval .)
This definition is formally dual to that of a fibration, which is required to satisfy the homotopy lifting property with respect to all spaces; this is one instance of the broader Eckmann–Hilton duality in topology.
Cofibrations are a fundamental concept of homotopy theory. Quillen has proposed the notion of model category as a formal framework for doing homotopy theory in more general categories; a model category is endowed with three distinguished classes of morphisms called fibrations, cofibrations and weak equivalences satisfying certain lifting and factorization axioms.
Definition
Homotopy theory
In what follows, let denote the unit interval.
A map of topological spaces is called a cofibrationpg 51 if for any map such that there is an extension to , meaning there is a map such that , we can extend a homotopy of maps to a homotopy of maps , whereWe can encode this condition in the following commutative diagramwhere is the path space of equipped with the compact-open topology.
For the notion of a cofibration in a model cat
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https://en.wikipedia.org/wiki/GarageGames
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GarageGames was a game technology and software developer. GarageGames was the parent company of GG Interactive, developers of educational technology in the areas of computer science, video game development and programming. In addition, the company has been a video game developer and publisher. GarageGames created several game engines targeted for indie development. Founded in Eugene, Oregon, the company had offices in Las Vegas, Nevada, United States and its headquarters in Vancouver, Washington. In 2007, GarageGames was acquired by IAC and the company was renamed TorquePowered. In 2011, the company was purchased by Graham Software Development and reverted to the original name GarageGames.
History
GarageGames was founded in Eugene, Oregon in 2000 by Jeff Tunnell, Tim Gift, Rick Overman, and Mark Frohnmayer. Working in their garage on severance checks, the founders derived the name GarageGames as a play off the term "garage band", and is meant to evoke a similar attitude in game development. The stated goal of the original founders of GarageGames was to offer licensing of game engines to virtually anyone, allowing independent game-makers more options in developing and publishing video games. In 2001, GarageGames released the Torque game engine. It was used to create the Tribes game series and was released at an initial price point to allow independent game developers access. Later the company expanded its product lines with additional tools, and more advanced engines and
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https://en.wikipedia.org/wiki/Intercalation%20%28chemistry%29
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In chemistry, intercalation is the reversible inclusion or insertion of a molecule (or ion) into layered materials with layered structures. Examples are found in graphite and transition metal dichalcogenides.
Examples
Graphite
One famous intercalation host is graphite, which intercalates potassium as a guest. Intercalation expands the van der Waals gap between sheets, which requires energy. Usually this energy is supplied by charge transfer between the guest and the host solid, i.e., redox. Two potassium graphite compounds are KC8 and KC24. Carbon fluorides (e.g., (CF)x and (C4F)) are prepared by reaction of fluorine with graphitic carbon. The color is greyish, white, or yellow. The bond between the carbon and fluorine atoms is covalent, thus fluorine is not intercalated. Such materials have been considered as a cathode in various lithium batteries.
Treating graphite with strong acids in the presence of oxidizing agents causes the graphite to oxidise. Graphite bisulfate, [C24]+[HSO4]−, is prepared by this approach using sulfuric acid and a little nitric acid or chromic acid. The analogous graphite perchlorate can be made similarly by reaction with perchloric acid.
Metal dichalcogenides
Another well-known family of intercalation hosts are the layered metal dichalcogenides such as titanium disulfide. In characteristic manner, intercalation is analyzed by X-ray diffraction, since the spacing between sheets increases, and by electrical conductivity, since charge transfer al
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https://en.wikipedia.org/wiki/Inclusion%20compound
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In host–guest chemistry, an inclusion compound (also known as an inclusion complex) is a chemical complex in which one chemical compound (the "host") has a cavity into which a "guest" compound can be accommodated. The interaction between the host and guest involves purely van der Waals bonding. The definition of inclusion compounds is very broad, extending to channels formed between molecules in a crystal lattice in which guest molecules can fit.
Examples and case studies
Calixarenes
Calixarenes and related formaldehyde-arene condensates are one class of hosts that form inclusion compounds. One famous illustration is the adduct with cyclobutadiene, which otherwise is unstable.
Cyclodextrins
Cyclodextrins are well established hosts for the formation of inclusion compounds. Illustrative is the case of ferrocene which is inserted into the cyclodextrin at 100 °C under hydrothermal conditions.
Cyclodextrin also forms inclusion compounds with fragrances. As a result, the fragrance molecules have a reduced vapor pressure and are more stable towards exposure to light and air. When incorporated into textiles the fragrance lasts much longer due to the slow-release action.
Non-examples
Cryptands and crown ethers typically do not form inclusion complexes since the guest is bound by forces stronger than van der Waals bonding. If the guest is enclosed on all sides so that it is 'trapped', the compound is known as a clathrate, not an inclusion complex. In molecular encapsulation,
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https://en.wikipedia.org/wiki/Host%E2%80%93guest%20chemistry
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In supramolecular chemistry, host–guest chemistry describes complexes that are composed of two or more molecules or ions that are held together in unique structural relationships by forces other than those of full covalent bonds. Host–guest chemistry encompasses the idea of molecular recognition and interactions through non-covalent bonding. Non-covalent bonding is critical in maintaining the 3D structure of large molecules, such as proteins and is involved in many biological processes in which large molecules bind specifically but transiently to one another.
Although non-covalent interactions could be roughly divided into those with more electrostatic or dispersive contributions, there are few commonly mentioned types of non-covalent interactions: ionic bonding, hydrogen bonding, van der Waals forces and hydrophobic interactions.
Host-guest interaction has raised dramatical attention since it was discovered. It is an important field, because many biological processes require the host-guest interaction, and it can be useful in some material designs. There are several typical host molecules, such as, cyclodextrin, crown ether, et al. In this article, the author will briefly introduce some examples of the host-guest molecules, discuss the thermodynamic and kinetic parameters, and discuss some applications.
Overview
Although van der Waals postulated the intermolecular interaction in 1873, in 1894, Fischer built a philosophical root for supramolecular chemistry. He pointed out
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https://en.wikipedia.org/wiki/Abuse%20of%20notation
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In mathematics, abuse of notation occurs when an author uses a mathematical notation in a way that is not entirely formally correct, but which might help simplify the exposition or suggest the correct intuition (while possibly minimizing errors and confusion at the same time). However, since the concept of formal/syntactical correctness depends on both time and context, certain notations in mathematics that are flagged as abuse in one context could be formally correct in one or more other contexts. Time-dependent abuses of notation may occur when novel notations are introduced to a theory some time before the theory is first formalized; these may be formally corrected by solidifying and/or otherwise improving the theory. Abuse of notation should be contrasted with misuse of notation, which does not have the presentational benefits of the former and should be avoided (such as the misuse of constants of integration).
A related concept is abuse of language or abuse of terminology, where a term — rather than a notation — is misused. Abuse of language is an almost synonymous expression for abuses that are non-notational by nature. For example, while the word representation properly designates a group homomorphism from a group G to GL(V), where V is a vector space, it is common to call V "a representation of G". Another common abuse of language consists in identifying two mathematical objects that are different, but canonically isomorphic. Other examples include identifying a con
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https://en.wikipedia.org/wiki/Vocaloid
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is a singing voice synthesizer software product. Its signal processing part was developed through a joint research project led by Kenmochi Hideki at the Pompeu Fabra University in Barcelona, Spain, in 2000 and was not originally intended to be a full commercial project. Backed by the Yamaha Corporation, it developed the software into the commercial product "Vocaloid" that was released in 2004.
The software enables users to synthesize "singing" by typing in lyrics and melody and also "speech" by typing in the script of the required words. It uses synthesizing technology with specially recorded vocals of voice actors or singers. To create a song, the user must input the melody and lyrics. A piano roll type interface is used to input the melody and the lyrics can be entered on each note. The software can change the stress of the pronunciations, add effects such as vibrato, or change the dynamics and tone of the voice.
Various voice banks have been released for use with the Vocaloid synthesizer technology. Each is sold as "a singer in a box" designed to act as a replacement for an actual singer. As such, they are released under a moe anthropomorphism. These avatars are also referred to as Vocaloids, and are often marketed as virtual idols; some have gone on to perform at live concerts as an on-stage projection.
The software was originally only available in English starting with the first Vocaloids Leon, Lola and Miriam by Zero-G, and Japanese with Meiko and Kaito made by Yamah
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https://en.wikipedia.org/wiki/Mahadev%20Satyanarayanan
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Mahadev "Satya" Satyanarayanan is an Indian experimental computer scientist, an ACM and IEEE fellow, and the Carnegie Group Professor of Computer Science at Carnegie Mellon University (CMU).
He is credited with many advances in edge computing, distributed systems, mobile computing, pervasive computing, and Internet of Things. His research focus is around performance, scalability, availability, and trust challenges in computing systems from the cloud to the mobile edge.
His work on the Andrew File System (AFS) was recognized with the ACM Software System Award in 2016 and the ACM SIGOPS Hall of Fame Award in 2008 for its influence and impact. His work on disconnected operation in Coda File System received the ACM SIGOPS Hall of Fame Award in 2015 and the inaugural ACM SIGMOBILE Test-of-Time Award in 2016.
He served as the founding Program Chairman of the IEEE/ACM Symposium on Edge Computing and the HotMobile workshops, the founding Editor-in-Chief of IEEE Pervasive Computing, and the founding Area Editor for the Synthesis Series on Mobile and Pervasive Computing. In addition, he was the founding director of Intel Research Pittsburgh and an advisor to the company Maginatics, which was acquired by EMC in 2014.
Education
He has a bachelor's and master's degree from Indian Institute of Technology, Madras in 1975 and 1977, and his Ph.D. in computer science from CMU in 1983.
Andrew File System
Satya was a principal architect and implementer of the Andrew File System (AFS), t
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https://en.wikipedia.org/wiki/Friedrich%20Konrad%20Beilstein
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Friedrich Konrad Beilstein () (17 February 183818 October 1906), was a Russian chemist and founder of the famous Handbuch der organischen Chemie (Handbook of Organic Chemistry). The first edition of this work, published in 1881, covered 1,500 compounds in 2,200 pages. This handbook is now known as the Beilstein database.
Life
Beilstein was born in Saint Petersburg in a family of German descent. Although he mastered the Russian language, he was educated in a German school. At the age of 15, he left for the University of Heidelberg where he studied chemistry under the tuition of Robert Bunsen. After two years he moved to the University of Munich and became a pupil of Justus Liebig, but soon returned to Heidelberg. There he acquired an interest and preference for organic chemistry, which became his major. For his Ph.D., Beilstein joined Friedrich Wöhler at the University of Göttingen, receiving his doctorate in February 1858, two days before his twentieth birthday. To increase his skill and experience he went to Paris to work with Adolphe Wurtz and Charles Friedel. In autumn of 1859, he accepted an invitation for a post of laboratory assistant at the University of Breslau offered to him by Carl Jacob Löwig, but soon changed it for Göttingen. There he became Privatdozent and lectured in organic chemistry. In 1865 he received the title of "Professor Extraordinarius" (i.e. assistant professor). In addition, he became editor of the journal the Zeitschrift für anorganische und allg
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https://en.wikipedia.org/wiki/Homogeneous%20polynomial
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In mathematics, a homogeneous polynomial, sometimes called quantic in older texts, is a polynomial whose nonzero terms all have the same degree. For example, is a homogeneous polynomial of degree 5, in two variables; the sum of the exponents in each term is always 5. The polynomial is not homogeneous, because the sum of exponents does not match from term to term. The function defined by a homogeneous polynomial is always a homogeneous function.
An algebraic form, or simply form, is a function defined by a homogeneous polynomial. A binary form is a form in two variables. A form is also a function defined on a vector space, which may be expressed as a homogeneous function of the coordinates over any basis.
A polynomial of degree 0 is always homogeneous; it is simply an element of the field or ring of the coefficients, usually called a constant or a scalar. A form of degree 1 is a linear form. A form of degree 2 is a quadratic form. In geometry, the Euclidean distance is the square root of a quadratic form.
Homogeneous polynomials are ubiquitous in mathematics and physics. They play a fundamental role in algebraic geometry, as a projective algebraic variety is defined as the set of the common zeros of a set of homogeneous polynomials.
Properties
A homogeneous polynomial defines a homogeneous function. This means that, if a multivariate polynomial P is homogeneous of degree d, then
for every in any field containing the coefficients of P. Conversely, if the above relati
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https://en.wikipedia.org/wiki/Z-order%20curve
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In mathematical analysis and computer science, functions which are Z-order, Lebesgue curve, Morton space-filling curve, Morton order or Morton code map multidimensional data to one dimension while preserving locality of the data points. It is named in France after Henri Lebesgue, who studied it in 1904, and named in the United States after Guy Macdonald Morton, who first applied the order to file sequencing in 1966. The z-value of a point in multidimensions is simply calculated by interleaving the binary representations of its coordinate values. Once the data are sorted into this ordering, any one-dimensional data structure can be used, such as simple one dimensional arrays, binary search trees, B-trees, skip lists or (with low significant bits truncated) hash tables. The resulting ordering can equivalently be described as the order one would get from a depth-first traversal of a quadtree or octree.
Coordinate values
The figure below shows the Z-values for the two dimensional case with integer coordinates 0 ≤ x ≤ 7, 0 ≤ y ≤ 7 (shown both in decimal and binary). Interleaving the binary coordinate values (starting to the right with the x-bit (in blue) and alternating to the left with the y-bit (in red)) yields the binary z-values (tilted by 45° as shown). Connecting the z-values in their numerical order produces the recursively Z-shaped curve. Two-dimensional Z-values are also known as quadkey values.
The Z-values of the x coordinates are described as binary numbers from the
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https://en.wikipedia.org/wiki/Exon%20trapping
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Exon trapping is a molecular biology technique to identify potential exons in a fragment of eukaryote DNA of unknown intron-exon structure. This is done to determine if the fragment is part of an expressed gene.
The genomic fragment is inserted into the intron of a 'splicing vector' consisting of a known exon - intron - exon sequence of DNA, and the vector is then inserted into an eukaryotic cell. If the fragment does not contain exons (i.e., consists solely of intron DNA), it will be spliced out together with the vector's original intron. On the other hand, if exons are contained, they will be part of the mature mRNA after transcription (with all intron material removed). The presence of 'trapped exons' can be detected by an increase in size of the mRNA, or through RT-PCR to amplify the DNA of interest.
The technique has largely been supplanted by the approach of sequencing cDNA generated from mRNA and then using bioinformatics tools such as NCBI's BLAST server to determine the source of the sequence, thereby identifying the appropriate exon-intron splice sites.
References
Gene expression
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https://en.wikipedia.org/wiki/Pseudoscalar%20meson
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In high-energy physics, a pseudoscalar meson is a meson with total spin 0 and odd parity (usually notated as
Pseudoscalar mesons are commonly seen in proton-proton scattering and proton-antiproton annihilation, and include the pion (), kaon (), eta (), and eta prime () particles, whose masses are known with great precision.
Among all of the mesons known to exist, in some sense, the pseudoscalars are the most well studied and understood.
History
The pion () was first proposed to exist by Yukawa in the 1930s as the primary force carrying boson of the Yukawa potential in nuclear interactions, and was later observed at nearly the same mass that he originally predicted for it. In the 1950s and 1960s, the pseudoscalar mesons began to proliferate, and were eventually organized into a multiplet according to Murray Gell-Mann's so-called "Eightfold Way".
Gell-Mann further predicted the existence of a ninth resonance in the pseudoscalar multiplet, which he originally called . Indeed, this particle was later found and is now known as the eta prime meson (). The structure of the pseudoscalar meson multiplet, and also the ground state baryon multiplets, led Gell-Mann (and Zweig, independently) to create the well known quark model.
The puzzle
Despite the pseudoscalar mesons' masses being known to high precision, and being the most well studied and understood mesons, the decay properties of the pseudoscalar mesons, particularly of eta () and eta-prime (), are somewhat contradictory t
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https://en.wikipedia.org/wiki/Scalar%20meson
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In high energy physics, a scalar meson is a meson with total spin 0 and even parity (usually noted as JP=0+). Compare to pseudoscalar meson. The first known scalar mesons have been observed since the late 1950s, with observations of numerous light states and heavier states proliferating since the 1980s.
Scalar mesons are most often observed in proton-antiproton annihilation, radiative decays of vector mesons, and meson-meson scattering.
Groups
The light (unflavored) scalar mesons may be divided into three groups:
mesons having a mass below 1 GeV/c2
mesons having a mass between 1 GeV/c2 and 2 GeV/c2
other radially-excited unflavored scalar mesons above 2 GeV/c2
Lower mass range
Since the late 1950s, the lightest scalar mesons were often interpreted within the framework of the linear sigma model, and many theorists still choose this interpretation of the scalar mesons as the chiral partners of the pseudoscalar meson multiplet.
With the re-introduction of the σ meson as an acceptable candidate for a light scalar meson in 1996 by Tornqvist and Roos, in-depth studies into the lightest scalar mesons were conducted with renewed interest.
Ever since Jaffe first suggested the existence of tetraquark multiplets in 1977, the lightest scalar mesons have been interpreted by some theorists to be possible tetraquark or meson-meson "molecule" states. The tetraquark interpretation works well with the MIT Bag Model of QCD, where the scalar tetraquarks are actually predicted to have low
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https://en.wikipedia.org/wiki/Vector%20meson
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In high energy physics, a vector meson is a meson with total spin 1 and odd parity (usually noted as ). Vector mesons have been seen in experiments since the 1960s, and are well known for their spectroscopic pattern of masses.
The vector mesons contrast with the pseudovector mesons, which also have a total spin 1 but instead have even parity. The vector and pseudovector mesons are also dissimilar in that the spectroscopy of vector mesons tends to show nearly pure states of constituent quark flavors, whereas pseudovector mesons and scalar mesons tend to be expressed as composites of mixed states.
Uniquely pure flavor states
Since the development of the quark model by Murray Gell-Mann (and also independently by George Zweig), the vector mesons have demonstrated the spectroscopy of pure states. The fact that the rho meson (ρ) and omega meson (ω) have nearly equal mass centered on 770–, while the phi meson (φ) has a higher mass around , indicates that the light-quark vector mesons appear in nearly pure states, with the φ meson having a nearly 100 percent amplitude of hidden strangeness.
These nearly pure states characteristic of the vector mesons are not at all evident in the pseudoscalar meson or scalar meson multiplets, and may be only slightly realized among the tensor meson and pseudovector meson multiplets. This fact makes the vector mesons an excellent probe of the quark flavor content of other types of mesons, measured through the respective decay rates of non-vector
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https://en.wikipedia.org/wiki/Pseudovector%20meson
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In high energy physics, a pseudovector meson or axial vector meson is a meson with total spin 1 and even parity (+) (usually noted as
Compare to a vector meson, which has a total spin 1 and odd parity
Charge parity (C) in addition to spatial parity (P)
The known pseudovector mesons fall into two different classes, all have even spatial parity ( P = "+" ), but they differ in another kind of parity called charge parity (C) which can be either even (+) or odd (−). The two types of pseudovector meson are:
those with odd charge parity
those with even charge parity
The 1 group has no intrinsic spin excitation , but do gain spin from angular momentum of the orbits of the two constituent quarks around their mutual center. The second group (1) have both intrinsic spin and with and coupling to
Pseudovector, or axial vector, mesons in the 1 category are most readily be seen in proton‑antiproton annihilation and pion‑nucleon scattering. The mesons in the 1 category are normally seen in proton-proton and pion-nucleon scattering.
Discrepant mass estimates
The difference between the two groups gives them slightly different masses, from the spin‑orbit coupling rule. Theoretically, the and mesons are in the 1 group, and should have heavier masses, according to the spin-orbit mass splitting. However, the measured masses of the mesons do not appear to follow the rule, as evidenced by the and mesons being heavier. There are considerable uncertainties in experim
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https://en.wikipedia.org/wiki/Geosynthetics
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Geosynthetics are synthetic products used to stabilize terrain. They are generally polymeric products used to solve civil engineering problems. This includes eight main product categories: geotextiles, geogrids, geonets, geomembranes, geosynthetic clay liners, geofoam, geocells and geocomposites. The polymeric nature of the products makes them suitable for use in the ground where high levels of durability are required. They can also be used in exposed applications. Geosynthetics are available in a wide range of forms and materials. These products have a wide range of applications and are currently used in many civil, geotechnical, transportation, geoenvironmental, hydraulic, and private development applications including roads, airfields, railroads, embankments, retaining structures, reservoirs, canals, dams, erosion control, sediment control, landfill liners, landfill covers, mining, aquaculture and agriculture.
History
Inclusions of different sorts mixed with soil have been used for thousands of years. They were used in roadway construction in Roman days to stabilize roadways and their edges. These early attempts were made of natural fibres, fabrics or vegetation mixed with soil to improve road quality, particularly when roads were built on unstable soil. They were also used to build steep slopes as with several pyramids in Egypt and walls as well. A fundamental problem with using natural materials (wood, cotton, etc.) in a buried environment is the biodegradation that oc
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https://en.wikipedia.org/wiki/School%20Mathematics%20Study%20Group
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The School Mathematics Study Group (SMSG) was an American academic think tank focused on the subject of reform in mathematics education. Directed by Edward G. Begle and financed by the National Science Foundation, the group was created in the wake of the Sputnik crisis in 1958 and tasked with creating and implementing mathematics curricula for primary and secondary education, which it did until its termination in 1977.
The efforts of the SMSG yielded a reform in mathematics education known as New Math which was promulgated in a series of reports, culminating in a series published by Random House called the New Mathematical Library (Vol. 1 is Ivan Niven's Numbers: Rational and Irrational). In the early years, SMSG also produced a set of draft textbooks in typewritten paperback format for elementary, middle and high school students.
Perhaps the most authoritative collection of materials from the School Mathematics Study Group is now housed in the Archives of American Mathematics in the University of Texas at Austin's Center for American History.
See also
Foundations of geometry
Further reading
1958 Letter from Ralph A. Raimi to Fred Quigley concerning the New Math
Whatever Happened to the New Math by Ralph A. Raimi
Some Technical Commentaries on Mathematics Education and History by Ralph A. Raimi
External links
The SMSG Collection at The Center for American History at UT
Archives of American Mathematics at the Center for American History at UT
Mathematics edu
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https://en.wikipedia.org/wiki/Sewall%20Wright
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Sewall Green Wright FRS(For) Honorary FRSE (December 21, 1889March 3, 1988) was an American geneticist known for his influential work on evolutionary theory and also for his work on path analysis. He was a founder of population genetics alongside Ronald Fisher and J. B. S. Haldane, which was a major step in the development of the modern synthesis combining genetics with evolution. He discovered the inbreeding coefficient and methods of computing it in pedigree animals. He extended this work to populations, computing the amount of inbreeding between members of populations as a result of random genetic drift, and along with Fisher he pioneered methods for computing the distribution of gene frequencies among populations as a result of the interaction of natural selection, mutation, migration and genetic drift. Wright also made major contributions to mammalian and biochemical genetics.
Biography
Sewall Wright was born in Melrose, Massachusetts, to Philip Green Wright and Elizabeth Quincy Sewall Wright. His parents were first cousins, an interesting fact in light of Wright's later research on inbreeding. The family moved three years later after Philip accepted a teaching job at Lombard College, a Universalist college in Galesburg, Illinois.
As a child, Wright helped his father and brother print and publish an early book of poems by his father's student Carl Sandburg. At the age of seven, in 1897, he wrote his first "book", entitled Wonders of Nature, and he published his last pa
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https://en.wikipedia.org/wiki/Sol%E2%80%93gel%20process
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In materials science, the sol–gel process is a method for producing solid materials from small molecules. The method is used for the fabrication of metal oxides, especially the oxides of silicon (Si) and titanium (Ti). The process involves conversion of monomers into a colloidal solution (sol) that acts as the precursor for an integrated network (or gel) of either discrete particles or network polymers. Typical precursors are metal alkoxides. Sol-gel process is used to produce ceramic nanoparticles.
Stages
In this chemical procedure, a "sol" (a colloidal solution) is formed that then gradually evolves towards the formation of a gel-like diphasic system containing both a liquid phase and solid phase whose morphologies range from discrete particles to continuous polymer networks. In the case of the colloid, the volume fraction of particles (or particle density) may be so low that a significant amount of fluid may need to be removed initially for the gel-like properties to be recognized. This can be accomplished in any number of ways. The simplest method is to allow time for sedimentation to occur, and then pour off the remaining liquid. Centrifugation can also be used to accelerate the process of phase separation.
Removal of the remaining liquid (solvent) phase requires a drying process, which is typically accompanied by a significant amount of shrinkage and densification. The rate at which the solvent can be removed is ultimately determined by the distribution of porosity i
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https://en.wikipedia.org/wiki/Sequence%20space
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In functional analysis and related areas of mathematics, a sequence space is a vector space whose elements are infinite sequences of real or complex numbers. Equivalently, it is a function space whose elements are functions from the natural numbers to the field K of real or complex numbers. The set of all such functions is naturally identified with the set of all possible infinite sequences with elements in K, and can be turned into a vector space under the operations of pointwise addition of functions and pointwise scalar multiplication. All sequence spaces are linear subspaces of this space. Sequence spaces are typically equipped with a norm, or at least the structure of a topological vector space.
The most important sequence spaces in analysis are the spaces, consisting of the -power summable sequences, with the p-norm. These are special cases of Lp spaces for the counting measure on the set of natural numbers. Other important classes of sequences like convergent sequences or null sequences form sequence spaces, respectively denoted c and c0, with the sup norm. Any sequence space can also be equipped with the topology of pointwise convergence, under which it becomes a special kind of Fréchet space called FK-space.
Definition
A sequence in a set is just an -valued map whose value at is denoted by instead of the usual parentheses notation
Space of all sequences
Let denote the field either of real or complex numbers. The set of all sequences of elements of
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https://en.wikipedia.org/wiki/Meanings%20of%20minor%20planet%20names%3A%2077001%E2%80%9378000
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77001–77100
|-id=044
| 77044 Galera-Rosillo || || Rebeca Galera-Rosillo (1988–2020) was a promising young Spanish scientist who earned her master's degree in astrophysics from the University of La Laguna. At the time of her death, she was close to defending her doctoral research on planetary nebulae at the Instituto de Astrofisica de Canarias. ||
|}
77101–77200
|-id=136
| 77136 Mendillo || || Michael Mendillo (born 1944), American professor of astronomy and electrical engineering at Boston University ||
|-id=138
| 77138 Puiching || 2001 EN || Pui Ching Middle School, Hong Kong. It was founded in 1889. ||
|-id=185
| 77185 Cherryh || || C. J. Cherryh (born 1942), an American science fiction and fantasy writer ||
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77201–77300
|-bgcolor=#f2f2f2
| colspan=4 align=center |
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77301–77400
|-id=318
| 77318 Danieltsui || || Daniel C. Tsui (born 1939), Chinese-American physicist and Nobelist, a graduate of Pui Ching Middle School in Hong Kong (see ) ||
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77401–77500
|-id=441
| 77441 Jouve || 2001 HU || Jacques Jouve (born 1929), involved in the construction of the Observatory of Saint-Veran, a station of the Paris Observatory that studies the solar corona, in the French Alps ||
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77501–77600
|-id=560
| 77560 Furusato || || Furusato is a well-known song in Japan. The word also means "country home". ||
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77601–77700
|-id=621
| 77621 Koten || || Pavel Koten (born 1972), a staff astronomer at the Astronomical Institute of the Academy of Sciences of
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https://en.wikipedia.org/wiki/Sturmian%20word
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In mathematics, a Sturmian word (Sturmian sequence or billiard sequence), named after Jacques Charles François Sturm, is a certain kind of infinitely long sequence of characters. Such a sequence can be generated by considering a game of English billiards on a square table. The struck ball will successively hit the vertical and horizontal edges labelled 0 and 1 generating a sequence of letters. This sequence is a Sturmian word.
Definition
Sturmian sequences can be defined strictly in terms of their combinatoric properties or geometrically as cutting sequences for lines of irrational slope or codings for irrational rotations. They are traditionally taken to be infinite sequences on the alphabet of the two symbols 0 and 1.
Combinatorial definitions
Sequences of low complexity
For an infinite sequence of symbols w, let σ(n) be the complexity function of w; i.e., σ(n) = the number of distinct contiguous subwords (factors) in w of length n. Then w is Sturmian if σ(n) = n + 1 for all n.
Balanced sequences
A set X of binary strings is called balanced if the Hamming weight of elements of X takes at most two distinct values. That is, for any |s|1 = k or |s|1 = k where |s|1 is the number of 1s in s.
Let w be an infinite sequence of 0s and 1s and let denote the set of all length-n subwords of w. The sequence w is Sturmian if is balanced for all n and w is not eventually periodic.
Geometric definitions
Cutting sequence of irrational
Let w be an infinite sequence of 0s
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https://en.wikipedia.org/wiki/ZbMATH%20Open
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zbMATH Open, formerly Zentralblatt MATH, is a major reviewing service providing reviews and abstracts for articles in pure and applied mathematics, produced by the Berlin office of FIZ Karlsruhe – Leibniz Institute for Information Infrastructure GmbH. Editors are the European Mathematical Society, FIZ Karlsruhe, and the Heidelberg Academy of Sciences. zbMATH is distributed by Springer Science+Business Media. It uses the Mathematics Subject Classification codes for organising reviews by topic.
History
Mathematicians Richard Courant, Otto Neugebauer, and Harald Bohr, together with the publisher Ferdinand Springer, took the initiative for a new mathematical reviewing journal. Harald Bohr worked in Copenhagen. Courant and Neugebauer were professors at the University of Göttingen. At that time, Göttingen was considered one of the central places for mathematical research, having appointed mathematicians like David Hilbert, Hermann Minkowski, Carl Runge, and Felix Klein, the great organiser of mathematics and physics in Göttingen. His dream of a building for an independent mathematical institute with a spacious and rich reference library was realised four years after his death. The credit for this achievement is particularly due to Richard Courant, who convinced the Rockefeller Foundation to donate a large amount of money for the construction.
The service was founded in 1931, by Otto Neugebauer as Zentralblatt für Mathematik und ihre Grenzgebiete. It contained the bibliographical
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https://en.wikipedia.org/wiki/Convergent%20synthesis
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In chemistry a convergent synthesis is a strategy that aims to improve the efficiency of multistep synthesis, most often in organic synthesis. In this type of synthesis several individual pieces of a complex molecule are synthesized in stage one, and then in stage two these pieces are combined to form the final product. In linear synthesis the overall yield quickly drops with each reaction step:
A → B → C → D
Suppose the yield is 50% for each reaction; the overall yield of D is only 12.5% from A.
In a convergent synthesis
A → B (50%)
C → D (50%)
B + D → E (25%)
the overall yield of E (25%) looks much better. Convergent synthesis is applied in the synthesis of complex molecules and involves fragment coupling and independent synthesis. This technique is more useful if the compound is large and symmetric, where at least two aspects of the molecule can be formed separately and still come together.
Examples:
Convergent synthesis is encountered in dendrimer synthesis where branches (with the number of generations preset) are connected to the central core.
Proteins of up to 300 amino acids are produced by a convergent approach using chemical ligation.
An example of its use in total synthesis is the final step (photochemical [2+2]cycloaddition) towards the compound biyouyanagin A:
See also
Divergent synthesis
References
Chemical synthesis
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https://en.wikipedia.org/wiki/Divergent%20synthesis
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In chemistry a divergent synthesis is a strategy with the aim to improve the efficiency of chemical synthesis. It is often an alternative to convergent synthesis or linear synthesis.
In one strategy divergent synthesis aims to generate a library of chemical compounds by first reacting a molecule with a set of reactants. The next generation of compounds is generated by further reactions with each compound in generation 1. This methodology quickly diverges to large numbers of new compounds
A generates A1, A2, A3, A4, A5 in generation 1
A1 generates A11, A12, A13 in generation 2 and so on.
An entire library of new chemical compounds, for instance saccharides, can be screened for desirable properties. In another strategy divergent synthesis starts from a molecule as a central core from which successive generations of building blocks are added. A good example is the divergent synthesis of dendrimers, for example, where in each generation a new monomer reacts to the growing surface of the sphere.
Diversity oriented synthesis
Diversity oriented synthesis or DOS is a strategy for quick access to molecule libraries with an emphasis on skeletal diversity. In one such application a Petasis reaction product (1) is functionalized with propargyl bromide leading to a starting compound (2) having 5 functional groups. This molecule can be subjected to a range of reagents yielding unique molecular skeletons in one generation.
DOS Drugs
Dosabulin
Gemmacin B
ML238
Robotnikinin
Reference
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https://en.wikipedia.org/wiki/Hubbard%20model
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The Hubbard model is an approximate model used to describe the transition between conducting and insulating systems. It is particularly useful in solid-state physics. The model is named for John Hubbard.
The Hubbard model states that each electron experiences competing forces: one pushes it to tunnel to neighboring atoms, while the other pushes it away from its neighbors. Its Hamiltonian thus has two terms: a kinetic term allowing for tunneling ("hopping") of particles between lattice sites and a potential term reflecting on-site interaction. The particles can either be fermions, as in Hubbard's original work, or bosons, in which case the model is referred to as the "Bose–Hubbard model".
The Hubbard model is a useful approximation for particles in a periodic potential at sufficiently low temperatures, where all the particles may be assumed to be in the lowest Bloch band, and long-range interactions between the particles can be ignored. If interactions between particles at different sites of the lattice are included, the model is often referred to as the "extended Hubbard model". In particular, the Hubbard term, most commonly denoted by U, is applied in first principles based simulations using Density Functional Theory, DFT. The inclusion of the Hubbard term in DFT simulations is important as this improves the prediction of electron localisation and thus it prevents the incorrect prediction of metallic conduction in insulating systems.
The Hubbard model introduces short-ran
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https://en.wikipedia.org/wiki/777%20%28number%29
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777 (seven hundred [and] seventy-seven) is the natural number following 776 and preceding 778. The number 777 is significant in numerous religious and political contexts.
In mathematics
777 is an odd, composite, palindromic repdigit. It is also a sphenic number, with 3, 7, and 37 as its prime factors. Its largest prime factor is a concatenation of its smaller two; the only other number below 1000 with this property is 138.
777 is also:
An extravagant number, a lucky number, a polite number, and an amenable number.
A deficient number, since the sum of its divisors is less than 2n.
A congruent number, as it is possible to make a right triangle with a rational number of sides whose area is 777.
An arithmetic number, since the average of its positive divisors is also an integer (152).
A repdigit in senary.
Religious significance
According to the Bible, Lamech, the father of Noah lived for 777 years. Some of the known religious connections to 777 are noted in the sections below.
Judaism
The numbers 3 and 7 both are considered "perfect numbers" under Hebrew tradition.
Christianity
According to the American publication, the Orthodox Study Bible, 777 represents the threefold perfection of the Trinity.
Thelema
777 is also found in the title of the book 777 and Other Qabalistic Writings of Aleister Crowley pertaining to the law of thelema.
Political significance
Afrikaner Weerstandsbeweging
The Afrikaner Resistance Movement (Afrikaner Weerstandsbeweging, AWB), a Boer-natio
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https://en.wikipedia.org/wiki/Fredrik%20Rosing%20Bull
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Fredrik Rosing Bull (25 December 1882 – 7 June 1925) was a Norwegian scientist, information technology pioneer, known for his work on improved punched card machines.
Bull was born in Kristiania (Oslo, Norway). In 1907 he finished his studies in civil engineering at the Technical School of Kristiania (Kristiania Tekniske Skole). In 1916 he was hired as a technical inspector for the insurance company Storebrand, where he developed an interest for punched card machines technology and began developing one of his own. In 1919 he obtained a patent for the machine, and in 1921 he prepared a team that took over the implementation of the machine at the company where Bull worked at that time, Storebrand. This team provided several new ideas for improving the Bull machine, rendering it superior to Hollerith's device - the precursor to the IBM punched card machine - in use at that time. Bull continued to develop his ideas, improving the machine, which became a success throughout Europe. He was diagnosed with cancer at an early age and died in 1925 when he was 42 years old. His patents were later sold in 1931 and constituted the basis for the founding of the French company Groupe Bull, a large information technology company operating in over 100 countries.
Family
Fredrik Bull was born in Kristiania (the present-day Oslo) to Dr. Ole Bornemann Bull (1842–1916) and his first wife Marie Cathrine Lund (1843–1884). Dr. Ole Bull was a renowned eye doctor. He collaborated with Gerhard Armauer
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https://en.wikipedia.org/wiki/Nearest%20neighbor
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Nearest neighbor may refer to:
Nearest neighbor search in pattern recognition and in computational geometry
Nearest-neighbor interpolation for interpolating data
Nearest neighbor graph in geometry
Nearest neighbor function in probability theory
Nearest neighbor decoding in coding theory
The k-nearest neighbor algorithm in machine learning, an application of generalized forms of nearest neighbor search and interpolation
The nearest neighbour algorithm for approximately solving the travelling salesman problem
The nearest neighbor method for determining the thermodynamics of nucleic acids
The nearest neighbor method for calculating distances between clusters in hierarchical clustering.
See also
Moore neighborhood
Von Neumann neighborhood
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https://en.wikipedia.org/wiki/Site-specific
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Site-specific may refer to:
Site-specific art
Site-specific recombination, in molecular biology
Site-specific theatre
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https://en.wikipedia.org/wiki/Andreas%20Sigismund%20Marggraf
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Andreas Sigismund Marggraf (; 3 March 1709 – 7 August 1782) was a German chemist from Berlin, then capital of the Margraviate of Brandenburg, and a pioneer of analytical chemistry. He isolated zinc in 1746 by heating calamine and carbon. Though he was not the first to do so, Marggraf is credited with carefully describing the process and establishing its basic theory. In 1747, Marggraf announced his discovery of sugar in beets and devised a method using alcohol to extract it. His student Franz Achard later devised an economical industrial method to extract the sugar in its pure form.
Life
Andreas Sigismund Marggraf was the son of the pharmacist Henning Christian Marggraf (1680–1754), who owned a pharmacy in Berlin and lectured at the Collegium Medico-Chirurgicum (medical/surgical school). Andreas came in contact with the pharmaceutical and medical business early and started studying at the medical school in 1725. He studied with Caspar Neumann in Berlin, Germany but he also visited pharmacies in other cities, including Frankfurt am Main and Strassbourg. He also attended lectures at the University of Halle. Andreas worked in his father's pharmacy and focused his work on chemistry. Later in his life he helped to reorganize the Societät der Wissenschaften into the Akademie der Wissenschaften (Prussian Academy of Science) and became the director of the physics section in 1760.
Even after a stroke in 1774, he continued work in the laboratories of the Akademie until his retirement
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https://en.wikipedia.org/wiki/MPS
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MPS, M.P.S., MPs, or mps may refer to:
Science and technology
Mucopolysaccharidosis, genetic lysosomal storage disorder
Mononuclear phagocyte system, cells in mammalian biology
Myofascial pain syndrome
Metallopanstimulin
Potassium peroxymonosulfate, oxidizer commonly used for pools and spas
Metre per second (m/s)
Matrix product state, method to describe quantum many-body states
Marginal propensity to save
Mean-preserving spread, in probability and statistics
Mail Preference Service, the Robinson list direct mail opt-out system
Master Production Schedule, plan for individual commodities to be produced
Method Performance Specifications, for analytical validation/verification of laboratory tests and systems required by the College of American Pathologists
Computing
Mobile Programming System, by William Waite in the 1960s
JetBrains MPS, Meta Programming System
MPS (format), the Mathematical Programming System, a computer file format used to describe mathematical programming problems
MultiProcessor Specification, Intel specification for multi-processor computers of x86 architecture
Moving Particle Semi-implicit Method, a computational method for the simulation of incompressible free surface flows
Messages per second, sent or received by a market data system; See Options Price Reporting Authority
Minimum Population Search, a computational method that optimizes a problem by iteratively trying to improve a set of candidate solutions
Language
Mandarin Phonetic S
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https://en.wikipedia.org/wiki/Eta%20Kappa%20Nu
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Eta Kappa Nu () or IEEE-HKN is the international honor society of the Institute of Electrical and Electronics Engineers (IEEE). Joining HKN is by invitation only. Membership is a lifelong designation for individuals who have distinguished themselves as students or as professionals in electrical engineering, computer engineering, computer science, and other fields of IEEE interest.
About HKN/IEEE-HKN
Eta Kappa Nu was founded in 1904 as an independent honor society for electrical engineering. It has expanded its scope through the years and it became an organizational unit within IEEE in 2010. Over 260 collegiate chapters have been chartered world-wide and more than 200,000 members have been elected to membership. These chapters recognize high scholarship through membership and foster a culture of service and volunteerism within their host departments. They are noted for student-led engagement with peers, faculty, and industry through tutoring, maker-space management, networking events, etc. Most members are inducted as students, but distinguished professionals may be inducted as well. The guiding ideals for membership eligibility of scholarship, character, and attitude have remained unchanged since the early years.
The corporate IEEE-HKN supports the chapters and the profession with a variety of signature activities. An annual Founders Day promotion during October encourages chapters to celebrate HKN and to engage in service in their local community in recognition of HKN's
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https://en.wikipedia.org/wiki/Scale%20space
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Scale-space theory is a framework for multi-scale signal representation developed by the computer vision, image processing and signal processing communities with complementary motivations from physics and biological vision. It is a formal theory for handling image structures at different scales, by representing an image as a one-parameter family of smoothed images, the scale-space representation, parametrized by the size of the smoothing kernel used for suppressing fine-scale structures. The parameter in this family is referred to as the scale parameter, with the interpretation that image structures of spatial size smaller than about have largely been smoothed away in the scale-space level at scale .
The main type of scale space is the linear (Gaussian) scale space, which has wide applicability as well as the attractive property of being possible to derive from a small set of scale-space axioms. The corresponding scale-space framework encompasses a theory for Gaussian derivative operators, which can be used as a basis for expressing a large class of visual operations for computerized systems that process visual information. This framework also allows visual operations to be made scale invariant, which is necessary for dealing with the size variations that may occur in image data, because real-world objects may be of different sizes and in addition the distance between the object and the camera may be unknown and may vary depending on the circumstances.
Definition
The no
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https://en.wikipedia.org/wiki/Binomial
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Binomial may refer to:
In mathematics
Binomial (polynomial), a polynomial with two terms
Binomial coefficient, numbers appearing in the expansions of powers of binomials
Binomial QMF, a perfect-reconstruction orthogonal wavelet decomposition
Binomial theorem, a theorem about powers of binomials
Binomial type, a property of sequences of polynomials
In probability and statistics
Binomial distribution, a type of probability distribution
Binomial process
Binomial test, a test of significance
In computing science
Binomial heap, a data structure
In linguistics
Binomial pair, a sequence of two or more words or phrases in the same grammatical category, having some semantic relationship and joined by some syntactic device
In biology
Binomial nomenclature, a Latin two-term name for a species, such as Sequoia sempervirens
In finance
Binomial options pricing model, a numerical method for the valuation of options
In politics
Binomial voting system, a voting system used in the parliamentary elections of Chile between 1989 and 2013
See also
List of factorial and binomial topics
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https://en.wikipedia.org/wiki/MusikCube
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musikcube is a free and open-source cross-platform, terminal-based audio player software and streaming server.
Features
musikcube is based on a modular plug-in architecture, and uses plug-ins written in C++. Plug-ins provide core functionality for audio decoding, data streaming, output device handling, metadata parsing, digital signal processing, and more. Plugins currently exist to provide support for many popular audio codecs, including MP3, M4A, Ogg Vorbis, and FLAC.
Internally, musikcube uses the SQLite database library for storing track and playlist metadata.
There is currently no support for Digital rights management.
musikcube is capable of streaming audio via an integrated server. An Android client also exists, allowing music to be streamed over local and wide-area networks.
Licensing
musikcube (and official plugins) are licensed under the BSD-3-Clause license.
See also
cmus
Music Player Daemon
Music on Console
Comparison of audio player software
External links
Free software programmed in C++
Linux media players
Windows media players
Free media players
2004 software
Free software that uses ncurses
Software using the BSD license
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https://en.wikipedia.org/wiki/Cycle%20decomposition
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In mathematics, the term cycle decomposition can mean:
Cycle decomposition (graph theory), a partitioning of the vertices of a graph into subsets, such that the vertices in each subset lie on a cycle
Cycle decomposition (group theory), a useful convention for expressing a permutation in terms of its constituent cycles
In commutative algebra and linear algebra, cyclic decomposition refers to writing a finitely generated module over a principal ideal domain as the direct sum of cyclic modules and one free module.
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https://en.wikipedia.org/wiki/Dephosphorylation
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In biochemistry, dephosphorylation is the removal of a phosphate (PO43−) group from an organic compound by hydrolysis. It is a reversible post-translational modification. Dephosphorylation and its counterpart, phosphorylation, activate and deactivate enzymes by detaching or attaching phosphoric esters and anhydrides. A notable occurrence of dephosphorylation is the conversion of ATP to ADP and inorganic phosphate.
Dephosphorylation employs a type of hydrolytic enzyme, or hydrolase, which cleaves ester bonds. The prominent hydrolase subclass used in dephosphorylation is phosphatase, which removes phosphate groups by hydrolysing phosphoric acid monoesters into a phosphate ion and a molecule with a free hydroxyl (-OH) group.
The reversible phosphorylation-dephosphorylation reaction occurs in every physiological process, making proper function of protein phosphatases necessary for organism viability. Because protein dephosphorylation is a key process involved in cell signalling, protein phosphatases are implicated in conditions such as cardiac disease, diabetes, and Alzheimer's disease.
History
The discovery of dephosphorylation came from a series of experiments examining the enzyme phosphorylase isolated from rabbit skeletal muscle. In 1955, Edwin Krebs and Edmond Fischer used radiolabeled ATP to determine that phosphate is added to the serine residue of phosphorylase to convert it from its b to a form via phosphorylation. Subsequently, Krebs and Fischer showed that this pho
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https://en.wikipedia.org/wiki/Data%20validation
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In computer science, data validation is the process of ensuring data has undergone data cleansing to confirm they have data quality, that is, that they are both correct and useful. It uses routines, often called "validation rules", "validation constraints", or "check routines", that check for correctness, meaningfulness, and security of data that are input to the system. The rules may be implemented through the automated facilities of a data dictionary, or by the inclusion of explicit application program validation logic of the computer and its application.
This is distinct from formal verification, which attempts to prove or disprove the correctness of algorithms for implementing a specification or property.
Overview
Data validation is intended to provide certain well-defined guarantees for fitness and consistency of data in an application or automated system. Data validation rules can be defined and designed using various methodologies, and be deployed in various contexts. Their implementation can use declarative data integrity rules, or procedure-based business rules.
The guarantees of data validation do not necessarily include accuracy, and it is possible for data entry errors such as misspellings to be accepted as valid. Other clerical and/or computer controls may be applied to reduce inaccuracy within a system.
Different kinds
In evaluating the basics of data validation, generalizations can be made regarding the different kinds of validation according to their sco
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https://en.wikipedia.org/wiki/E.%20J.%20Conway
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Edward Joseph Conway FRS (3 July 1894 – 29 December 1968) was an Irish biochemist known for works pertaining to electrolyte physiology and analytical chemistry.
Education
Conway was born in Nenagh, North Tipperary and educated at Blackrock College and University College Dublin, graduating M.Sc.. After winning a studentship to the University of Frankfurt am Main, where he was awarded D.Sc., he returned to Ireland to become the first Professor of Biochemistry and Pharmacology at University College Dublin in 1932, a post he held until 1963.
Research
Conway was one of Ireland's most distinguished scientists; he was a world authority on electrolyte physiology, and in general on the physiology of the inorganic constituents of living tissue. He published over 120 papers, as well as two books: Microdiffusion Analysis and Volumetric Error and The Biochemistry of Gastric Acid Secretion.
Awards
Conway was elected a Fellow of the Royal Society in 1947, his application citation stating that he was "Distinguished for investigations of chemical and physiochemical processes in living tissues, including a quantitative interpretation of the processes underlying potassium accumulation in isolated muscle, with applications to resting potentials and related questions; the exact determination of blood ammonia, the ammonia increase in shed blood, and studies of the deaminase involved; general structural relations of the mammalian kidney, and studies of diffusion rates through tissues; biochemica
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https://en.wikipedia.org/wiki/Raney%20nickel
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Raney nickel , also called spongy nickel, is a fine-grained solid composed mostly of nickel derived from a nickel–aluminium alloy. Several grades are known, of which most are gray solids. Some are pyrophoric, but most are used as air-stable slurries. Raney nickel is used as a reagent and as a catalyst in organic chemistry. It was developed in 1926 by American engineer Murray Raney for the hydrogenation of vegetable oils.
Raney is a registered trademark of W. R. Grace and Company. Other major producers are Evonik and Johnson Matthey.
Preparation
Alloy preparation
The Ni–Al alloy is prepared by dissolving nickel in molten aluminium followed by cooling ("quenching"). Depending on the Ni:Al ratio, quenching produces a number of different phases.
During the quenching procedure, small amounts of a third metal, such as zinc or chromium, are added to enhance the activity of the resulting catalyst. This third metal is called a "promoter". The promoter changes the mixture from a binary alloy to a ternary alloy, which can lead to different quenching and leaching properties during activation.
Activation
In the activation process, the alloy, usually as a fine powder, is treated with a concentrated solution of sodium hydroxide. The simplified leaching reaction is given by the following chemical equation:
2 Al + 2 NaOH + 6 H2O → 2 Na[Al(OH)4] + 3 H2
The formation of sodium aluminate (Na[Al(OH)4]) requires that solutions of high concentration of sodium hydroxide be used to avoid the fo
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https://en.wikipedia.org/wiki/Rado%27s%20theorem%20%28Ramsey%20theory%29
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Rado's theorem is a theorem from the branch of mathematics known as Ramsey theory. It is named for the German mathematician Richard Rado. It was proved in his thesis, Studien zur Kombinatorik.
Statement
Let be a system of linear equations, where is a matrix with integer entries. This system is said to be -regular if, for every -coloring of the natural numbers 1, 2, 3, ..., the system has a monochromatic solution. A system is regular if it is r-regular for all r ≥ 1.
Rado's theorem states that a system is regular if and only if the matrix A satisfies the columns condition. Let ci denote the i-th column of A. The matrix A satisfies the columns condition provided that there exists a partition C1, C2, ..., Cn of the column indices such that if , then
s1 = 0
for all i ≥ 2, si can be written as a rational linear combination of the cjs in all the Ck with k < i. This means that si is in the linear subspace of Q'm spanned by the set of the cj's.
Special cases
Folkman's theorem, the statement that there exist arbitrarily large sets of integers all of whose nonempty sums are monochromatic, may be seen as a special case of Rado's theorem concerning the regularity of the system of equations
where T ranges over each nonempty subset of the set
Other special cases of Rado's theorem are Schur's theorem and Van der Waerden's theorem. For proving the former apply Rado's theorem to the matrix . For Van der Waerden's theorem with m chosen to be length of the monochromati
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https://en.wikipedia.org/wiki/Edward%20Norton%20Lorenz
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Edward Norton Lorenz (May 23, 1917 – April 16, 2008) was an American mathematician and meteorologist who established the theoretical basis of weather and climate predictability, as well as the basis for computer-aided atmospheric physics and meteorology. He is best known as the founder of modern chaos theory, a branch of mathematics focusing on the behavior of dynamical systems that are highly sensitive to initial conditions.
His discovery of deterministic chaos "profoundly influenced a wide range of basic sciences and brought about one of the most dramatic changes in mankind's view of nature since Sir Isaac Newton," according to the committee that awarded him the 1991 Kyoto Prize for basic sciences in the field of earth and planetary sciences.
Biographical information
Lorenz was born in 1917 in West Hartford, Connecticut. He acquired an early love of science from both sides of his family. His father, Edward Henry Lorenz (1882-1956), majored in mechanical engineering at the Massachusetts Institute of Technology, and his maternal grandfather, Lewis M. Norton, developed the first course in chemical engineering at MIT in 1888. Meanwhile, his mother, Grace Peloubet Norton (1887-1943), instilled in Lorenz a deep interest in games, particularly chess.
Later in life, Lorenz lived in Cambridge, Massachusetts with his wife, Jane Loban, and their three children, Nancy, Cheryl, and Edward. He was an avid outdoorsman, who enjoyed hiking, climbing, and cross-country skiing. He kept up
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https://en.wikipedia.org/wiki/One-pot%20synthesis
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In chemistry a one-pot synthesis is a strategy to improve the efficiency of a chemical reaction in which a reactant is subjected to successive chemical reactions in just one reactor. This is much desired by chemists because avoiding a lengthy separation process and purification of the intermediate chemical compounds can save time and resources while increasing chemical yield.
An example of a one-pot synthesis is the total synthesis of tropinone or the Gassman indole synthesis. Sequential one-pot syntheses can be used to generate even complex targets with multiple stereocentres, such as oseltamivir, which may significantly shorten the number of steps required overall and have important commercial implications.
A sequential one-pot synthesis with reagents added to a reactor one at a time and without work-up is also called a telescoping synthesis.
In one such procedure the reaction of 3-N-tosylaminophenol I with acrolein II affords a hydroxyl substituted quinoline III through 4 sequential steps without workup of the intermediate products (see image). The addition of acrolein (blue) is a Michael reaction catalyzed by N,N-diisopropylamine, the presence of ethanol converts the aldehyde group to an acetal but this process is reversed when hydrochloric acid is introduced (red). The enolate reacts as an electrophile in a Friedel-Crafts reaction with ring-closure. The alcohol group is eliminated in presence of potassium hydroxide (green) and when in the final step the reaction mediu
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https://en.wikipedia.org/wiki/Joseph%20Proudman
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Joseph Proudman (30 December 1888 – 26 June 1975), CBE, FRS was a distinguished British mathematician and oceanographer of international repute. His theoretical studies into the oceanic tides not only "solved practically all the remaining tidal problems which are soluble within the framework of classical hydrodynamics and analytical mathematics" but laid the basis of a tidal prediction service developed with Arthur Doodson of great international importance.
Education
Proudman was born in the village of Unsworth, near Bury, Lancashire on 30 December 1888. He attended primary schools at Unsworth and Bold and from 1902 to 1907 he was a pupil-teacher at Farnworth primary school. He augmented his secondary schooling by having extra lessons before school officially started in the morning and also by attending evening classes at Widnes Technical School studying art, mathematics and physiography. He was awarded the Tate Technical Science entrance scholarship and entered the University of Liverpool in 1907. He graduated with first class honours in 1910 winning the Hudson prize for geometry and the Derby scholarship. With this and the award of an entrance exhibition, he had a second brilliant undergraduate career, studying pure and applied mathematics at Trinity College, Cambridge where he became a Wrangler with distinction graduating in 1912.
Career
It was his tutor Rev. E. W. Barnes who suggested that Proudman write to Horace Lamb at Manchester for a suitable topic of research. Thi
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https://en.wikipedia.org/wiki/Mapping%20cone%20%28topology%29
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In mathematics, especially homotopy theory, the mapping cone is a construction of topology, analogous to a quotient space. It is also called the homotopy cofiber, and also notated . Its dual, a fibration, is called the mapping fibre. The mapping cone can be understood to be a mapping cylinder , with one end of the cylinder collapsed to a point. Thus, mapping cones are frequently applied in the homotopy theory of pointed spaces.
Definition
Given a map , the mapping cone is defined to be the quotient space of the mapping cylinder with respect to the equivalence relation , . Here denotes the unit interval [0, 1] with its standard topology. Note that some authors (like J. Peter May) use the opposite convention, switching 0 and 1.
Visually, one takes the cone on X (the cylinder with one end (the 0 end) identified to a point), and glues the other end onto Y via the map f (the identification of the 1 end).
Coarsely, one is taking the quotient space by the image of X, so ; this is not precisely correct because of point-set issues, but is the philosophy, and is made precise by such results as the homology of a pair and the notion of an n-connected map.
The above is the definition for a map of unpointed spaces; for a map of pointed spaces (so ), one also identifies all of ; formally, Thus one end and the "seam" are all identified with
Example of circle
If is the circle , the mapping cone can be considered as the quotient space of the disjoint union of Y with the disk f
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https://en.wikipedia.org/wiki/Ted%20Selker
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Edwin Joseph Selker, better known as Ted Selker, is an American computer scientist known for his user interface inventions.
Biography
Selker graduated from Brown University in 1979 with a BS in Applied Mathematics, and from the University of Massachusetts Amherst with an MS in Computer and Information Sciences in 1981. From June 1981 to 1983 he worked as research assistant in the Stanford University, Robotics Laboratory. One of his projects was a collaborative display system for the WAITS system of the Stanford Artificial Intelligence Laboratory (SAIL).
He worked for Atari for a year, then returned to Stanford to teach for a year.
Selker joined IBM in August 1985, first at the Thomas J. Watson Research Center. He graduated with a PhD from City University of New York in 1992. His thesis was titled "A Framework for Proactive Interactive Adaptive Computer Help".
He then moved to the IBM Almaden Research Center where he founded and directed the User Systems Ergonomics Research lab.
He was made an IBM Fellow in 1996. Selker holds 67 US patents. He developed the pointing stick (known as TrackPoint) technology which are the distinctive feature of the ThinkPad line of laptop computers (designed, developed and sold by IBM but produced by Lenovo since 2005).
Selker joined the MIT faculty in September 1999. He headed the Context Aware Computing group at the MIT Media Lab and was the MIT director of The Voting Technology Project and Design Intelligence.
He joined the faculty of Carne
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https://en.wikipedia.org/wiki/Restriction%20digest
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A restriction digest is a procedure used in molecular biology to prepare DNA for analysis or other processing. It is sometimes termed DNA fragmentation, though this term is used for other procedures as well. In a restriction digest, DNA molecules are cleaved at specific restriction sites of 4-12 nucleotides in length by use of restriction enzymes which recognize these sequences.
The resulting digested DNA is very often selectively amplified using polymerase chain reaction (PCR), making it more suitable for analytical techniques such as agarose gel electrophoresis, and chromatography. It is used in genetic fingerprinting, plasmid subcloning, and RFLP analysis.
Restriction site
A given restriction enzyme cuts DNA segments within a specific nucleotide sequence, at what is called a restriction site. These recognition sequences are typically four, six, eight, ten, or twelve nucleotides long and generally palindromic (i.e. the same nucleotide sequence in the 5' – 3' direction). Because there are only so many ways to arrange the four nucleotides that compose DNA (Adenine, Thymine, Guanine and Cytosine) into a four- to twelve-nucleotide sequence, recognition sequences tend to occur by chance in any long sequence. Restriction enzymes specific to hundreds of distinct sequences have been identified and synthesized for sale to laboratories, and as a result, several potential "restriction sites" appear in almost any gene or locus of interest on any chromosome. Furthermore, almost all
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https://en.wikipedia.org/wiki/Bernhard%20Rensch
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Bernhard Rensch (21 January 1900 – 4 April 1990) was a German evolutionary biologist and ornithologist who did field work in Indonesia and India. Starting his scientific career with pro-Lamarckian views, he shifted to selectionism and became one of the architects of the modern synthesis in evolutionary biology, which he popularised in Germany. Besides his work on how environmental factors influenced the evolution of geographically isolated populations and on evolution above the species level, which contributed to the modern synthesis, he also worked extensively in the area of animal behavior (ethology) and on philosophical aspects of biological science. His education and scientific work were interrupted by service in the German military during both World War I and World War II.
Biography
Rensch was born in Thale and as a young boy, he took an interest in observing the natural world and discovered a talent for drawing and painting. He served in the German army from 1917–1920 and began to observe natural phenomena while he was held prisoner in France. He returned to Germany and began his studies on feather structure under Valentin Haecker (1864–1927) who had himself studied under August Weismann. Until the 1930s Rensch held anti-Darwinian and Lamarckian views. Rensch also took an interest in the philosophy of science and was fascinated by Theodor Ziehen (1862–1950). Rensch also studied expressionist painting and in later life examined the biological roots of art. He received h
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https://en.wikipedia.org/wiki/Quantum%201/f%20noise
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Quantum 1/f noise is an intrinsic and fundamental part of quantum mechanics. Fighter pilots, photographers, and scientists all appreciate the higher quality of images and signals resulting from the consideration of quantum 1/f noise. Engineers have battled unwanted 1/f noise since 1925, giving it poetic names (such as flicker noise, funkelrauschen, bruit de scintillation, etc.) due to its mysterious nature. The Quantum 1/f noise theory was developed about 50 years later, describing the nature of 1/f noise, allowing it the be explained and calculated via straightforward engineering formulas. It allows for the low-noise optimization of materials, devices and systems of most high-technology applications of modern industry and science. The theory includes the conventional and coherent quantum 1/f effects (Q1/fE). Both effects are combined in a general engineering formula, and present in Q1/f noise, which is itself most of fundamental 1/f noise. The latter is defined as the result of the simultaneous presence of nonlinearity and a certain type of homogeneity in a system, and can be quantum or classical.
The conventional Q1/fE represents 1/f fluctuations caused by bremsstrahlung, decoherence and interference in the scattering of charged particles off one another, in tunneling or in any other process in solid state physics and in general.
Other noise data sets
It has also recently been claimed that 1/f noise has been seen in higher ordered self constructing functions, as well
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https://en.wikipedia.org/wiki/Denaturation
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Denaturation may refer to:
Denaturation (biochemistry), a structural change in macromolecules caused by extreme conditions
Denaturation (fissile materials), transforming fissile materials so that they cannot be used in nuclear weapons
Denaturation (food), intentional adulteration of food or drink rendering it unfit for consumption while remaining suitable for other uses
See also
Denatured alcohol, also known as methylated spirit
Denaturalization, the reverse of naturalization, when a state deprives one of its citizens of his or her citizenship
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https://en.wikipedia.org/wiki/IVC
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IVC can refer to:
Places
Invercargill Airport, New Zealand, IATA code
Ivory Coast, UNDP country code
Oflag IV-C, a German World War II prisoner-of-war camp in Colditz Castle
Education
Impington Village College
Irvine Valley College
Imperial Valley College
Medicine and biology
Involuntary commitment
Inferior vena cava
Inferior vena cava filter
Intravenous Vitamin C
In vitro compartmentalization
Music
International Vocal Competition 's-Hertogenbosch, a competition for opera, oratorio and lied singers
Science and technology
Indus Valley Civilisation, a Bronze Age civilisation centralized along the Indus River
Internet Video Coding, a "free-of-charge" MPEG video coding standard
Inter-vehicle communication
Other uses
Ignatian Volunteer Corps
International Video Corporation, a manufacturer of videotape recorders in the 1960s and 70s
Individually ventilated cage
Invacare
International Vale Tudo Championship
In-vessel composting
See also
4C (disambiguation)
C4 (disambiguation)
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https://en.wikipedia.org/wiki/Robert%20van%20de%20Geijn
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Robert A. van de Geijn is a Professor of Computer Sciences at the University of Texas at Austin. He received his B.S. in Mathematics and Computer Science (1981) from the University of Wisconsin–Madison and his Ph.D. in Applied Mathematics (1987) from the University of Maryland, College Park. His areas of interest include numerical analysis and parallel processing.
Major work
Van de Geijn's has turned toward the theoretical, in particular with his development of the Formal Linear Algebra Method (FLAME). FLAME is an original effort at formalizing the efficient derivation of linear algebra algorithms that are provably correct. This approach benefits from his less theoretical experience; it is designed to ultimately lead to the efficient design and implementation of these algorithms.
He is the principal author of the widely cited book. Using PLAPACK—parallel linear algebra package. Scientific and engineering computation. Cambridge, Mass: MIT Press, 1997.
Personal
Robert van de Geijn was born on August 14, 1962, in the Netherlands. He later moved to the United States, where he enrolled at the University of Wisconsin-Madison in 1978. He is married to a fellow academic, Margaret Myers. They have three children, and now live in a historic house in downtown Pflugerville, Texas.
References
External links
Robert A. van de Geijn
Year of birth missing (living people)
Living people
American computer scientists
Geijn, Robert
Geijn, Robert
University of Texas at Austin faculty
Univ
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https://en.wikipedia.org/wiki/Michael%20Garey
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Michael Randolph Garey (born November 19, 1945) is a computer science researcher, and co-author (with David S. Johnson) of Computers and Intractability: A Guide to the Theory of NP-completeness. He and Johnson received the 1979 Frederick W. Lanchester Prize from the Operations Research Society of America for the book. Garey earned his PhD in computer science in 1970 from the University of Wisconsin–Madison. He was employed by AT&T Bell Laboratories in the Mathematical Sciences Research Center from 1970 until his retirement in 1999. For his last 11 years with the organization, he served as its director. His technical specialties included discrete algorithms and computational complexity, approximation algorithms, scheduling theory, and graph theory. From 1978 until 1981 he served as Editor-in-Chief of the Journal of the Association for Computing Machinery. In 1995, Garey was inducted as a Fellow of the Association for Computing Machinery.
References
External links
Garey's personal web page
University of Wisconsin–Madison College of Letters and Science alumni
American computer scientists
Fellows of the Association for Computing Machinery
Theoretical computer scientists
Living people
1945 births
American textbook writers
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https://en.wikipedia.org/wiki/Metric%20dimension
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In mathematics, metric dimension may refer to:
Metric dimension (graph theory), the minimum number of vertices of an undirected graph G in a subset S of G such that all other vertices are uniquely determined by their distances to the vertices in S
Minkowski–Bouligand dimension (also called the metric dimension), a way of determining the dimension of a fractal set in a Euclidean space by counting the number of fixed-size boxes needed to cover the set as a function of the box size
Equilateral dimension of a metric space (also called the metric dimension), the maximum number of points at equal distances from each other
Hausdorff dimension, an extended non-negative real number associated with any metric space that generalizes the notion of the dimension of a real vector space
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https://en.wikipedia.org/wiki/Indentation%20hardness
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Indentation hardness tests are used in mechanical engineering to determine the hardness of a material to deformation. Several such tests exist, wherein the examined material is indented until an impression is formed; these tests can be performed on a macroscopic or microscopic scale.
When testing metals, indentation hardness correlates roughly linearly with tensile strength, but it is an imperfect correlation often limited to small ranges of strength and hardness for each indentation geometry. This relation permits economically important nondestructive testing of bulk metal deliveries with lightweight, even portable equipment, such as hand-held Rockwell hardness testers.
Material hardness
Different techniques are used to quantify material characteristics at smaller scales. Measuring mechanical properties for materials, for instance, of thin films, cannot be done using conventional uniaxial tensile testing. As a result, techniques testing material "hardness" by indenting a material with a very small impression have been developed to attempt to estimate these properties.
Hardness measurements quantify the resistance of a material to plastic deformation. Indentation hardness tests compose the majority of processes used to determine material hardness, and can be divided into three classes: macro, micro and nanoindentation tests. Microindentation tests typically have forces less than . Hardness, however, cannot be considered to be a fundamental material property. Classical ha
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https://en.wikipedia.org/wiki/David%20Rubincam
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David Perry Rubincam (born February 27, 1947) is an American geophysicist with specialties in solid-earth geophysics, planetary geodynamics and celestial mechanics. He has worked as a civilian scientist for the National Aeronautics and Space Administration since 1978. The main-belt asteroid 9921 Rubincam was named in his honor.
Education
He received a B.S. in Physics (1970), M.S. in Physics (1972), and Ph.D. in Physics (1973) from the University of Maryland, College Park.
Career
From 1974-1976 he served as a Resident Research Associate at the National Academy of Sciences and National Research Council.
From 1976-1978 he served as Lead Analyst in Geophysics at Wolf Research and Development Group, EG&G, Inc.
From 1978 to present, he has served as a Geophysicist in the Laboratory for Terrestrial Physics, National Aeronautics and Space Administration (NASA), Goddard Space Flight Center in Greenbelt, Maryland. He studies secular effects in the solar system such as tidal friction, the Yarkovsky effect, and the Yarkovsky–O'Keefe–Radzievskii–Paddack effect (YORP) effect. One of his many contributions while at NASA was conducting research to understand the dynamics of orbital decay of artificial Earth satellites. Current interests include asteroids and asteroid pairs.
Society memberships
Rubincam is a member of the American Geophysical Union and the American Association for the Advancement of Science.
Bibliography
2000 "Dynamical Evolution of Main Belt Meteoroids: Numeri
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https://en.wikipedia.org/wiki/Microwave%20chemistry
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Microwave chemistry is the science of applying microwave radiation to chemical reactions. Microwaves act as high frequency electric fields and will generally heat any material containing mobile electric charges, such as polar molecules in a solvent or conducting ions in a solid. Polar solvents are heated as their component molecules are forced to rotate with the field and lose energy in collisions. Semiconducting and conducting samples heat when ions or electrons within them form an electric current and energy is lost due to the electrical resistance of the material. Microwave heating in the laboratory began to gain wide acceptance following papers in 1986, although the use of microwave heating in chemical modification can be traced back to the 1950s. Although occasionally known by such acronyms as MAOS (microwave-assisted organic synthesis), MEC (microwave-enhanced chemistry) or MORE synthesis (microwave-organic reaction enhancement), these acronyms have had little acceptance outside a small number of groups.
Heating effect
Conventional heating usually involves the use of a furnace or oil bath, which heats the walls of the reactor by convection or conduction. The core of the sample takes much longer to achieve the target temperature, e.g. when heating a large sample of ceramic bricks.
Acting as internal heat source, microwave absorption is able to heat the target compounds without heating the entire furnace or oil bath, which saves time and energy. It is also able to hea
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https://en.wikipedia.org/wiki/Dry%20media%20reaction
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A dry media reaction or solid-state reaction or solventless reaction is a chemical reaction system in the absence of a solvent. The drive for the development of dry media reactions in chemistry is
economics (save money on solvents)
ease of purification (no solvent removal post-synthesis)
high reaction rate (due to high concentration of reactants)
environmentally friendly (solvent is not required), see green chemistry
Drawbacks to overcome:
reactants should mix to a homogeneous system
high viscosity in reactant system
unsuitable for solvent assisted chemical reactions
problems with dissipating heat safely; risk of thermal runaway
side reactions accelerated
if reagents are solids, very high energy consumption from milling
In one type of solventless reaction a liquid reactant is used neat, for instance the reaction of 1-bromonaphthalene with Lawesson's reagent is done with no added liquid solvent, but the 1-bromonaphthalene acts as a solvent.
A reaction which is closer to a true solventless reaction is a Knoevenagel condensation of ketones with (malononitrile) where a 1:1 mixture of the two reactants (and ammonium acetate) is irradiated in a microwave oven.
Colin Raston's research group have been responsible for a number of new solvent free reactions. In some of these reactions all the starting materials are solids, they are ground together with some sodium hydroxide to form a liquid, which turns into a paste which then hardens to a solid.
In another development
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https://en.wikipedia.org/wiki/Particle%20acceleration
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In a compressible sound transmission medium - mainly air - air particles get an accelerated motion: the particle acceleration or sound acceleration with the symbol a in metre/second2. In acoustics or physics, acceleration (symbol: a) is defined as the rate of change (or time derivative) of velocity. It is thus a vector quantity with dimension length/time2. In SI units, this is m/s2.
To accelerate an object (air particle) is to change its velocity over a period. Acceleration is defined technically as "the rate of change of velocity of an object with respect to time" and is given by the equation
where
a is the acceleration vector
v is the velocity vector expressed in m/s
t is time expressed in seconds.
This equation gives a the units of m/(s·s), or m/s2 (read as "metres per second per second", or "metres per second squared").
An alternative equation is:
where
is the average acceleration (m/s2)
is the initial velocity (m/s)
is the final velocity (m/s)
is the time interval (s)
Transverse acceleration (perpendicular to velocity) causes change in direction. If it is constant in magnitude and changing in direction with the velocity, we get a circular motion. For this centripetal acceleration we have
One common unit of acceleration is g-force, one g being the acceleration caused by the gravity of Earth.
In classical mechanics, acceleration is related to force and mass (assumed to be constant) by way of Newton's second law:
Equations in terms of other measurements
Th
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https://en.wikipedia.org/wiki/Interlink%20Computer%20Sciences
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Interlink Computer Sciences, of Fremont, California, was a developer of hardware and software that allowed IBM mainframe computers running the MVS operating system to be connected to non-IBM networks.
Interlink was founded in 1983 by Lambert Onuma, Fred Wright, Karl Johnson and Greg Thompson, formerly of Digital Equipment Corporation. The company's first product, called simply Interlink, allowed IBM MVS mainframes to be connected to VAX computers on a DECnet network. Later a VM/DECnet product was developed in cooperation with Dupont to link IBM VM/CMS systems with a DECnet network interconnecting e-mail, file, tape, and storage access, terminal emulation, a program-to-program API, and enabling DECnet to be tunneled over an SNA LU6.2 network.
In 1990, Interlink acquired a product called ACCES/MVS from Advanced Computer Communications, which implemented a native TCP/IP protocol stack on the MVS and VM operating systems and within CICS regions. First released in 1986, ACCES/MVS had been the first commercial TCP/IP implementation for MVS mainframes. Interlink developed and marketed this product as SNS/TCPaccess. The prefix was later dropped, and TCPaccess became the company's main focus of development by the mid-1990s.
Meanwhile, in 1989, IBM had introduced its own TCP/IP offering on MVS. This product had been ported from the VM operating system, and required expensive and inefficient protocol conversions. Interlink was able to successfully sell TCPaccess as a more eff
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https://en.wikipedia.org/wiki/Analyte
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An analyte, component (in clinical chemistry), titrand (in titrations), or chemical species is a substance or chemical constituent that is of interest in an analytical procedure. The purest substances are referred to as analytes, such as 24 karat gold, NaCl, water, etc. In reality, no substance has been found to be 100% pure in its quality, so a substance that is found to be most pure (for some metals, 99% after electrolysis) is called an analyte.
See also
Analytical chemistry
Immunoassay
Magnetic immunoassay
References
Analytical chemistry
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https://en.wikipedia.org/wiki/Ap%C3%A9ry%27s%20theorem
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In mathematics, Apéry's theorem is a result in number theory that states the Apéry's constant ζ(3) is irrational. That is, the number
cannot be written as a fraction where p and q are integers. The theorem is named after Roger Apéry.
The special values of the Riemann zeta function at even integers () can be shown in terms of Bernoulli numbers to be irrational, while it remains open whether the function's values are in general rational or not at the odd integers () (though they are conjectured to be irrational).
History
Leonhard Euler proved that if n is a positive integer then
for some rational number . Specifically, writing the infinite series on the left as , he showed
where the are the rational Bernoulli numbers. Once it was proved that is always irrational, this showed that is irrational for all positive integers n.
No such representation in terms of π is known for the so-called zeta constants for odd arguments, the values for positive integers n. It has been conjectured that the ratios of these quantities
are transcendental for every integer .
Because of this, no proof could be found to show that the zeta constants with odd arguments were irrational, even though they were (and still are) all believed to be transcendental. However, in June 1978, Roger Apéry gave a talk titled "Sur l'irrationalité de ζ(3)." During the course of the talk he outlined proofs that and were irrational, the latter using methods simplified from those used to tackle the former r
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https://en.wikipedia.org/wiki/TCPaccess
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TCPaccess is a software product which implements the TCP/IP protocol suite on IBM mainframe computers using the MVS operating system. It was developed in 1986 by Advanced Computer Communications under the name ACCES/MVS, and was the first commercial TCP/IP implementation for MVS mainframes. It is usually associated with Interlink Computer Sciences, which developed and marketed the product from 1990 until 1999, and is frequently referred to as "the Interlink stack".
The product was marketed by Cisco Systems as Cisco IOS for S/390. It is currently offered by Computer Associates as Unicenter TCPaccess Communications Server.
External links
Cisco IOS for S/390 – From Cisco Systems.
Internet Protocol based network software
IBM mainframe software
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https://en.wikipedia.org/wiki/Wurtz%20reaction
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In organic chemistry, the Wurtz reaction, named after Charles Adolphe Wurtz, is a coupling reaction whereby two alkyl halides are treated with sodium metal to form a higher alkane.
2 R−X + 2 Na → R−R + 2 NaX
The reaction is of little value except for intramolecular versions. A related reaction, which combines alkyl halides with aryl halides is called the Wurtz–Fittig reaction.
Mechanism
The reaction proceeds by an initial metal–halogen exchange, which is described with the following idealized stoichiometry:
R−X + 2 M → RM + MX
This step may involve the intermediacy of radical species R·. The conversion resembles the formation of a Grignard reagent. The RM intermediates have been isolated in several cases. The radical is susceptible to diverse reactions.
The organometallic intermediate (RM) next reacts with the alkyl halide (RX) forming a new carbon–carbon covalent bond.
RM + RX → R−R + MX
The process resembles an SN2 reaction, but the mechanism is probably complex.
Examples and reaction conditions
The reaction is intolerant of a range of functional groups which would be attacked by sodium. For similar reasons, the reaction is conducted in unreactive solvents such as ethers. In efforts to improve the reaction yields, other metals have also been tested to effect the Wurtz-like couplings: silver, zinc, iron, activated copper, indium, as well as mixture of manganese and copper chloride.
Wurtz coupling is useful in closing small, especially three-membered, rings. In
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https://en.wikipedia.org/wiki/Coupling%20reaction
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In organic chemistry, a coupling reaction is a type of reaction in which two reactant molecules are bonded together. Such reactions often require the aid of a metal catalyst. In one important reaction type, a main group organometallic compound of the type R-M (where R = organic group, M = main group centre metal atom) reacts with an organic halide of the type R'-X with formation of a new carbon-carbon bond in the product R-R'. The most common type of coupling reaction is the cross coupling reaction.
Richard F. Heck, Ei-ichi Negishi, and Akira Suzuki were awarded the 2010 Nobel Prize in Chemistry for developing palladium-catalyzed cross coupling reactions.
Broadly speaking, two types of coupling reactions are recognized:
Homocouplings joining two identical partners. The product is symmetrical
Heterocouplings joining two different partners. These reactions are also called cross-coupling reactions. The product is unsymmetrical, .
Homo-coupling types
Coupling reactions are illustrated by the Ullmann reaction:
Cross-coupling types
Applications
Coupling reactions are routinely employed in the preparation of pharmaceuticals. Conjugated polymers are prepared using this technology as well.
References
Organometallic chemistry
Carbon-carbon bond forming reactions
Catalysis
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https://en.wikipedia.org/wiki/National%20Renewable%20Energy%20Laboratory
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The National Renewable Energy Laboratory (NREL) in the US specializes in the research and development of renewable energy, energy efficiency, energy systems integration, and sustainable transportation. NREL is a federally funded research and development center sponsored by the Department of Energy and operated by the Alliance for Sustainable Energy, a joint venture between MRIGlobal and Battelle. Located in Golden, Colorado, NREL is home to the National Center for Photovoltaics, the National Bioenergy Center, and the National Wind Technology Center.
History
The Solar Energy Research, Development and Demonstration Act of 1974 established the Solar Energy Research Institute, which opened in 1977 and was operated by MRIGlobal. Under the Jimmy Carter administration, its activities went beyond research and development in solar energy as it tried to popularize knowledge about already existing technologies, like passive solar. During the Ronald Reagan administration the institute's budget was cut by nearly 90%; many employees were "reduced in force", and the institute's activities were reduced to R&D. In September 1991, the institute was designated a national laboratory of the U.S. Department of Energy by President George H.W. Bush ,and its name was changed to the National Renewable Energy Laboratory.
Renewed interest in energy problems improved the laboratory's position, but funding has fluctuated over the years. In 2011, anticipated congressional budget shortfalls led to a vol
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https://en.wikipedia.org/wiki/Viability
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Viability or viable may refer to:
Biology, medicine or ecology
Viability selection, the selection of individual organisms who can survive until they are able to reproduce
Fetal viability, the ability of a fetus to survive outside of the uterus
Genetic viability, chance of a population of plants or animals to avoid the problems of inbreeding
Minimum viable population, a lower bound on the population of a species, such that it can survive in the wild
Population viability analysis, a species-specific method of risk assessment frequently used in conservation biology
Viable count, of viable cells
Business
Viability study, a study of the profitability of a business concept which is to be converted into a business
Minimum viable product, in product development, a strategy used for fast and quantitative market testing of a product or product feature
Other uses
Viable Paradise, an annual one-week writing workshop held each autumn on Martha's Vineyard
Viable system model, a scientific model by Stafford Beer of the organization of a viable or autonomous system
Viable system theory, a modelling approach that enables complex strategic and operative business and financial systems to be modelled and explored.
Viability theory, an area of mathematics that studies the evolution of dynamical systems under constraints to the system's state
See also
Viability assay, an assay to determine the ability of cells or tissues to maintain or recover its viability
Via (disambiguation)
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https://en.wikipedia.org/wiki/Radiological%20and%20Environmental%20Sciences%20Laboratory
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The Radiological and Environmental Sciences Laboratory (RESL) is a government-owned and government-operated laboratory operated by the U.S. Department of Energy Idaho Operations Office. It reports directly to the DOE-ID Assistant Manager for Technical Programs and Operations, and is located at the IRC in Idaho Falls, Idaho. RESL and its predecessor organizations have been part of the DOE-ID since 1949.
RESL provides an unbiased technical component to DOE oversight of contractor operations at DOE facilities and sites. As a reference laboratory, it conducts cost-effective measurement quality assurance programs that help assure that key DOE missions are completed in a safe and environmentally responsible manner. By assuring the quality and stability of key laboratory measurement systems throughout DOE, and by providing expert technical assistance to improve those systems and programs, it assures the reliability of data on which decisions are based. As a result, customers and stakeholders have greater confidence that those programs protect workers, the public, and the environment.
RESL's core scientific capabilities are in analytical chemistry and radiation calibrations and measurements. The RESL staff includes professional chemists, physicists, health physicists, engineers, computer programmers, and technicians, many of whom have advanced degrees. Their professional involvement includes participating in professional society activities, acting as reviewers and participating on
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https://en.wikipedia.org/wiki/M%C3%A4rklin%20Digital
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Märklin Digital was among the earlier digital model railway control systems. It was a comprehensive system including locomotive decoders (based on a Motorola chip), central control (Märklin 6020/6021), a computer interface (Märklin 6050), turnout decoders (Märklin 6083), digital relays (Märklin 6084) and feedback modules (Märklin s88/6088). The initial system was presented at the 1979 Nürnberg International Toy Fair, released in Europe in 1985 and the USA in 1986 under the name Digital H0.
Operation
Conventional analog control of model railways works by varying the track power and any locomotive on the track will respond by running at a speed roughly proportional to the power. For multiple trains, sidings must have a switch to isolate trains standing there and leave the track dead. For multiple controllers, the layout must be divided into sections isolated from each other and each with its own controller and current supply. All accessories such as signals and turnouts require individual switches and cables, making wiring very complex.
With analog systems, fine control of locomotives requires knowledge of the individual characteristics; gradients and curves require constant adjustment and low speed running is both difficult and liable to stalling. Any train lighting will vary in intensity with the power and be off when the locomotive is stopped.
Digital control supplies constant power to the track with the power being switched many times a second to provide the "bits" of da
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https://en.wikipedia.org/wiki/Bjarte%20Breiteig
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Bjarte Breiteig (born 17 March 1974) is a Norwegian short story writer.
Background
Bjarte Breiteig was born in Kristiansand, 1974. He studied physics at NTNU in Trondheim, but dropped out after two years to study literature at the same place. He has studied at the Skrivekunstakademiet and the University of Bergen. He now resides in Oslo.
Work
Published in 1998, Bjarte Breiteig's first short story collection, Fantomsmerter, received glowing reviews and Aschehougs debutantpris. His next collection of short stories, Surrogater was published in 2000. In 2003, Bjarte Breiteig was one of five young authors whose work was included in a collection of short stories published under the title of Borders by the European literary project Scritture Giovani. This means Breiteig's short story Fremover was translated into Welsh, German, English and Italian. He received the Anders Jahres pris for yngre kunstnere (Anders Jahre's prize for young artists) in 2004. In 2006, his third short story collection, Folk har begynt å banke på, was published and resulted in his being awarded the Max Wiel Nygaards legat (Max Wiel Nygaards Endowment). He was also awarded the Mads Wiel Nygaards Endowment in 2006.
Bibliography
Fantomsmerter (Phantom pains), 1998
Surrogater (Surrogates), 2000
Folk har begynt å banke på (Someone is knocking at the door), 2006
Île Sainte-Marie, 2013
Mine fem år som far, 2014
Den andre viljen, 2016
External links
Breiteig, Bjarte - Official homepage (Norwegian)
Breiteig, B
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https://en.wikipedia.org/wiki/John%20Henry%20Holland
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John Henry Holland (February 2, 1929 – August 9, 2015) was an American scientist and professor of psychology and electrical engineering and computer science at the University of Michigan, Ann Arbor. He was a pioneer in what became known as genetic algorithms.
Biography
John Henry Holland was born on 2 February 1929 in Fort Wayne, Allen County, Indiana, son of Gustave A. Holland (b. 24 July 1896 in Russian Poland; only son of Christopher Holland and Appolonia Greiber / Graeber; three sisters) and Mildred P. Gfroerer (b. 1 July 1901
in Columbus Grove, Ohio; the second of three daughters of John Joseph Gfroerer and Ila Savilla "Ily S." Kiefer). He had one younger sister, Shirley Ann "Hollie" Holland (b. about 1931; m1. c.1955 John William Ringgenberg (div. bef. 3 Aug 1968, d. 1982), had issue; m2. 2003 to Albert Vernon "Vern" Kinner (d. 2015)).
Holland studied physics at the Massachusetts Institute of Technology and received a B.S. degree in 1950. He then studied Mathematics at the University of Michigan, receiving an M.A. in 1954. In 1959, he received the first computer science Ph.D. from the University of Michigan. He was a Professor of psychology and Professor of electrical engineering and computer science at the University of Michigan, Ann Arbor. He held visiting positions at the Rowland Institute for Science and the University of Bergen.
"Holland is best known for his role as a founding father of the complex systems approach. In particular, he developed genetic algorithm
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https://en.wikipedia.org/wiki/AGT
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AGT may refer to:
Arts and entertainment
A Global Threat, an American street punk band (1997–2007)
Adventure Game Toolkit, a 1987 text-based gaming system
America's Got Talent, an NBC reality TV show
Australia's Got Talent, a Seven Network reality TV show
Biology and medicine
Agaritine, a hydrazine derivative
AGT, a codon for the amino acid Serine
Angiotensinogen, a protein
Antiglobulin test, also known as Coombs test
O-6-methylguanine-DNA methyltransferase, a protein
Government
Alberta Government Telephones, a Canadian public utility (1906–1991)
Attorney General of Tanzania
Attorney-General of Tasmania
Attorney General of Texas
Attorney General of Tonga
Places
Aldrington railway station, Sussex, England (CRS code: AGT)
Guaraní International Airport, Paraguay (IATA code: AGT)
AGT Tower, Edmonton, Alberta, Canada
Vehicular technologies
Automated guideway transit, a driverless rail system
Honeywell AGT1500, a gas turbine engine—oft used in military tanks
Other uses
Advanced Global Trading, a Dubai firm
Central Cagayan Agta language of the Philippines (by ISO code)
Dries van Agt, Dutch Prime Minister 1977–1982
See also
Agta (disambiguation)
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https://en.wikipedia.org/wiki/Neighbourhood%20system
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In topology and related areas of mathematics, the neighbourhood system, complete system of neighbourhoods, or neighbourhood filter for a point in a topological space is the collection of all neighbourhoods of
Definitions
Neighbourhood of a point or set
An of a point (or subset) in a topological space is any open subset of that contains
A is any subset that contains open neighbourhood of ;
explicitly, is a neighbourhood of in if and only if there exists some open subset with .
Equivalently, a neighborhood of is any set that contains in its topological interior.
Importantly, a "neighbourhood" does have to be an open set; those neighbourhoods that also happen to be open sets are known as "open neighbourhoods."
Similarly, a neighbourhood that is also a closed (respectively, compact, connected, etc.) set is called a (respectively, , , etc.).
There are many other types of neighbourhoods that are used in topology and related fields like functional analysis.
The family of all neighbourhoods having a certain "useful" property often forms a neighbourhood basis, although many times, these neighbourhoods are not necessarily open. Locally compact spaces, for example, are those spaces that, at every point, have a neighbourhood basis consisting entirely of compact sets.
Neighbourhood filter
The neighbourhood system for a point (or non-empty subset) is a filter called the The neighbourhood filter for a point is the same as the neighbourhood filter of the sin
|
https://en.wikipedia.org/wiki/Theon%20of%20Smyrna
|
Theon of Smyrna ( Theon ho Smyrnaios, gen. Θέωνος Theonos; fl. 100 CE) was a Greek philosopher and mathematician, whose works were strongly influenced by the Pythagorean school of thought. His surviving On Mathematics Useful for the Understanding of Plato is an introductory survey of Greek mathematics.
Life
Little is known about the life of Theon of Smyrna. A bust created at his death, and dedicated by his son, was discovered at Smyrna, and art historians date it to around 135 CE. Ptolemy refers several times in his Almagest to a Theon who made observations at Alexandria, but it is uncertain whether he is referring to Theon of Smyrna. The lunar impact crater Theon Senior is named for him.
Works
Theon wrote several commentaries on the works of mathematicians and philosophers of the time, including works on the philosophy of Plato. Most of these works are lost. The one major survivor is his On Mathematics Useful for the Understanding of Plato. A second work concerning the order in which to study Plato's works has recently been discovered in an Arabic translation.
On Mathematics Useful for the Understanding of Plato
His On Mathematics Useful for the Understanding of Plato is not a commentary on Plato's writings but rather a general handbook for a student of mathematics. It is not so much a groundbreaking work as a reference work of ideas already known at the time. Its status as a compilation of already-established knowledge and its thorough citation of earlier sources is part
|
https://en.wikipedia.org/wiki/Sergei%20Chetverikov
|
Sergei Sergeevich Chetverikov (; 6 May 1880 – 2 July 1959) was a Russian biologist and one of the early contributors to the development of the field of genetics. His research showed how early genetic theories applied to natural populations, and has therefore contributed towards the modern synthesis of evolutionary theory.
Between the two World Wars, Soviet biological research managed to connect genetics with field research on natural populations. Chetverikov lead a team at the Nikolai Koltsov Institute of Experimental Biology in Moscow, and in 1926 produced what should have been one of the landmark papers of the modern synthesis. However, published only in Russian, it was largely ignored in the English-speaking world (though J.B.S. Haldane possessed a translation).
Chetverikov influenced several Russian geneticists who later came to work in the West, such as Theodosius Dobzhansky and Nikolay Timofeev-Ressovsky, both of whom continued to work in a similar style. The significance of Chetverikov's work came to light much later, by which time the evolutionary synthesis was virtually complete.
He was arrested by OGPU in 1929 and sent to exile to Yekaterinburg for five years. He later moved to Nizhny Novgorod and organized the Department of Genetics at Gorky University. He was dismissed from his post at the behest of Lysenko in 1948.
References
External links
The Synthesis Of S. S. Chetverikov
Article about him (Russian)
His biography (Russian)
Population geneticists
Russi
|
https://en.wikipedia.org/wiki/Harmonic%20%28mathematics%29
|
In mathematics, a number of concepts employ the word harmonic. The similarity of this terminology to that of music is not accidental: the equations of motion of vibrating strings, drums and columns of air are given by formulas involving Laplacians; the solutions to which are given by eigenvalues corresponding to their modes of vibration. Thus, the term "harmonic" is applied when one is considering functions with sinusoidal variations, or solutions of Laplace's equation and related concepts.
Mathematical terms whose names include "harmonic" include:
Projective harmonic conjugate
Cross-ratio
Harmonic analysis
Harmonic conjugate
Harmonic form
Harmonic function
Harmonic mean
Harmonic mode
Harmonic number
Harmonic series
Alternating harmonic series
Harmonic tremor
Spherical harmonics
Mathematical terminology
Harmonic analysis
|
https://en.wikipedia.org/wiki/Proper
|
Proper may refer to:
Mathematics
Proper map, in topology, a property of continuous function between topological spaces, if inverse images of compact subsets are compact
Proper morphism, in algebraic geometry, an analogue of a proper map for algebraic varieties
Proper transfer function, a transfer function in control theory in which the degree of the numerator does not exceed the degree of the denominator
Proper equilibrium, in game theory, a refinement of the Nash equilibrium
Proper subset
Proper space
Proper complex random variable
Other uses
Proper (liturgy), the part of a Christian liturgy that is specific to the date within the Liturgical Year
Proper frame, such system of reference in which object is stationary (non moving), sometimes also called a co-moving frame
Proper (heraldry), in heraldry, means depicted in natural colors
Proper Records, a UK record label
Proper (album), an album by Into It. Over It. released in 2011
Proper (often capitalized PROPER), a corrected release in response to a previously released online video or movie that contains transcoding or other playback errors
See also
Acceptable (disambiguation)
|
https://en.wikipedia.org/wiki/Peter%20Coveney
|
Coveney is a Professor of Physical Chemistry, Honorary Professor of Computer Science, and the Director of the Centre for Computational Science (CCS) and Associate Director of the Advanced Research Computing Centre at University College London (UCL). He is also a Professor of Applied High Performance Computing at University of Amsterdam (UvA) and Professor Adjunct at the Yale School of Medicine, Yale University. He is a Fellow of the Royal Academy of Engineering and Member of Academia Europaea. Coveney is active in a broad area of interdisciplinary research including condensed matter physics and chemistry, materials science, as well as life and medical sciences in all of which high performance computing plays a major role. The citation about Coveney on his election as a FREng says: Coveney "has made outstanding contributions across a wide range of scientific and engineering fields, including physics, chemistry, chemical engineering, materials, computer science, high performance computing and biomedicine, much of it harnessing the power of supercomputing to conduct original research at unprecedented space and time scales. He has shown outstanding leadership across these fields, manifested through running multiple initiatives and multi-partner interdisciplinary grants, in the UK, Europe and the US. His achievements at national and international level in advocacy and enablement are exceptional".
Education
Coveney was awarded a Doctor of Philosophy degree from the University
|
https://en.wikipedia.org/wiki/Photocatalysis
|
In chemistry, photocatalysis is the acceleration of a photoreaction in the presence of a photocatalyst, the excited state of which "repeatedly interacts with the reaction partners forming reaction intermediates and regenerates itself after each cycle of such interactions." In many cases, the catalyst is a solid that upon irradiation with UV- or visible light generates electron–hole pairs that generate free radicals. Photocatalysts belong to three main groups; heterogeneous, homogeneous, and plasmonic antenna-reactor catalysts. The use of each catalysts depends on the preferred application and required catalysis reaction.
History
Early mentions (1911–1938)
The earliest mention came in 1911, when German chemist Dr. Alexander Eibner integrated the concept in his research of the illumination of zinc oxide (ZnO) on the bleaching of the dark blue pigment, Prussian blue. Around this time, Bruner and Kozak published an article discussing the deterioration of oxalic acid in the presence of uranyl salts under illumination, while in 1913, Landau published an article explaining the phenomenon of photocatalysis. Their contributions led to the development of actinometric measurements, measurements that provide the basis of determining photon flux in photochemical reactions. After a hiatus, in 1921, Baly et al. used ferric hydroxides and colloidal uranium salts as catalysts for the creation of formaldehyde under visible light.
In 1938 Doodeve and Kitchener discovered that , a highly-st
|
https://en.wikipedia.org/wiki/Frobenius%20group
|
In mathematics, a Frobenius group is a transitive permutation group on a finite set, such that no non-trivial element
fixes more than one point and some non-trivial element fixes a point.
They are named after F. G. Frobenius.
Structure
Suppose G is a Frobenius group consisting of permutations of a set X. A subgroup H of G fixing a point of X is called a Frobenius complement. The identity element together with all elements not in any conjugate of H form a normal subgroup called the Frobenius kernel K. (This is a theorem due to ; there is still no proof of this theorem that does not use character theory, although see .) The Frobenius group G is the semidirect product of K and H:
.
Both the Frobenius kernel and the Frobenius complement have very restricted structures. proved that the Frobenius kernel K is a nilpotent group. If H has even order then K is abelian. The Frobenius complement H has the property that every subgroup whose order is the product of 2 primes is cyclic; this implies that its Sylow subgroups are cyclic or generalized quaternion groups. Any group such that all Sylow subgroups are cyclic is called a Z-group, and in particular must be a metacyclic group: this means it is the extension of two cyclic groups. If a Frobenius complement H is not solvable then Zassenhaus showed that it
has a normal subgroup of index 1 or 2 that is the product of SL(2,5) and a metacyclic group of order coprime to 30. In particular, if a Frobenius complement coincides with its de
|
https://en.wikipedia.org/wiki/James%20Martin%20%28author%29
|
James Martin (19 October 1933 – 24 June 2013) was an English information technology consultant and author, known for his work on information technology engineering.
Biography
James Martin was born on 19 October 1933 in Ashby-de-la-Zouch, England. He earned a degree in physics at Keble College, Oxford.
Martin joined IBM in 1959, and from the 1980s on, established several IT consultancy firms. Starting in 1981 with Dixon Doll and Tony Carter he established DMW (Doll Martin Worldwide) in London, UK, which was later renamed James Martin Associates (JMA), which was (partly) bought by Texas Instruments Software in 1991. He later co-founded Database Design Inc. (DDI), in Ann Arbor, Michigan, to promulgate his database design techniques and to develop tools to help implement them. After becoming the market leader in information technology engineering software, DDI was renamed KnowledgeWare and eventually purchased by Fran Tarkenton, who took it public.
Martin was awarded an honorary fellowship by Keble College, Oxford and an honorary Doctor of Science degree by the University of Warwick in July 2009. He gave the Turing Lecture in 2008. According to Computerworld'''s 25th anniversary issue, he was ranked fourth among the 25 individuals who have most influenced the world of computer science.
Personal life
From the 1990s onwards, Martin lived on his own private island, Agar's Island, in Bermuda, where he died on 24 June 2013, apparently in a swimming accident.
Work
Martin was a
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https://en.wikipedia.org/wiki/Physical%20paradox
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A physical paradox is an apparent contradiction in physical descriptions of the universe. While many physical paradoxes have accepted resolutions, others defy resolution and may indicate flaws in theory. In physics as in all of science, contradictions and paradoxes are generally assumed to be artifacts of error and incompleteness because reality is assumed to be completely consistent, although this is itself a philosophical assumption. When, as in fields such as quantum physics and relativity theory, existing assumptions about reality have been shown to break down, this has usually been dealt with by changing our understanding of reality to a new one which remains self-consistent in the presence of the new evidence.
Paradoxes relating to false assumptions
Certain physical paradoxes defy common sense predictions about physical situations. In some cases, this is the result of modern physics correctly describing the natural world in circumstances which are far outside of everyday experience. For example, special relativity has traditionally yielded two common paradoxes: the twin paradox and the ladder paradox. Both of these paradoxes involve thought experiments which defy traditional common sense assumptions about time and space. In particular, the effects of time dilation and length contraction are used in both of these paradoxes to create situations which seemingly contradict each other. It turns out that the fundamental postulate of special relativity that the speed of ligh
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https://en.wikipedia.org/wiki/R62
|
R62 may refer to:
R62 (New York City Subway car)
R62 (South Africa), a road
HD 32034, a star
, a destroyer of the Royal Navy
, an aircraft carrier of the Royal Navy
R62: Possible risk of impaired fertility, a risk phrase in chemistry
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https://en.wikipedia.org/wiki/Priestley%20Medal
|
The Priestley Medal is the highest honor conferred by the American Chemical Society (ACS) and is awarded for distinguished service in the field of chemistry. Established in 1922, the award is named after Joseph Priestley, one of the discoverers of oxygen, who immigrated to the United States of America in 1794. The ACS formed in 1876, spearheaded by a group of chemists who had met two years previously in Priestley's home.
The Priestley Medal is among the most distinguished awards in the chemical sciences, behind the Wolf Prize in Chemistry and the Nobel Prize in Chemistry. Consequently, it is commonly awarded to scientists who are advanced in their fields, as it is intended to commemorate lifetime achievement. When the ACS started presenting the Priestley Medal in 1923, they intended to award it every three years. This continued until 1944, when it became an annual award.
Recipients
1920s
1923 Ira Remsen
1926 Edgar Fahs Smith
1929 Francis P. Garvan
1930s
1932 Charles L. Parsons
1935 William A. Noyes
1938 Marston T. Bogert
1940s
1941 Thomas Midgley, Jr.
1944 James Bryant Conant
1945 Ian Heilbron
1946 Roger Adams
1947 Warren K. Lewis
1948 Edward R. Weidlein
1949 Arthur B. Lamb
1950s
1950 Charles A. Kraus
1951 E. J. Crane
1952 Samuel C. Lind
1953 Sir Robert Robinson
1954 W. Albert Noyes, Jr. (son of William A. Noyes)
1955 Charles A. Thomas
1956 Carl S. Marvel
1957 Farrington Daniels
1958 Ernest H. Volwiler
1959 Hermann Irving Schlesinger
1960s
19
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https://en.wikipedia.org/wiki/Termination
|
Termination may refer to:
Science
Termination (geomorphology), the period of time of relatively rapid change from cold, glacial conditions to warm interglacial condition
Termination factor, in genetics, part of the process of transcribing RNA
Termination type, in lithic reduction, a characteristic indicating the manner in which the distal end of a lithic flake detaches from a core
Chain termination, in chemistry, a chemical reaction which halts polymerization
Termination shock, in solar studies, a feature of the heliosphere
Terminating computation, in computer science
Termination analysis, a form of program analysis in computer science
Termination proof, a mathematical proof concerning the termination of a program
Termination (term rewriting), in particular for term rewriting systems
Technology
Electrical termination, ending a wire or cable properly to prevent interference
Termination of wires to a
Crimp connection
Electrical connector
Solder joint
Abort (computing), ending a processing activity
Other
Termination (album), by Japanese band 9mm Parabellum Bullet
Indian termination policy, U.S. government policy affecting status of Native Americans, implemented in 1953
Terminate with extreme prejudice, a euphemism for assassination
Abortion, as the termination of a pregnancy
"Termination", a song by Iron Butterfly on their 1968 album In-A-Gadda-Da-Vida
Cancellation (television), the termination of a television program
Termination of employment
Dismissal (employment), the te
|
https://en.wikipedia.org/wiki/Robert%20Altenkirch
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Robert A. Altenkirch was the President of University of Alabama in Huntsville and the New Jersey Institute of Technology.
Life
Altenkirch holds a B.S. from Purdue University, a M.S. from the University of California, Berkeley, and a Ph.D. from Purdue University, all in Mechanical Engineering. He is the author of over 50 publications and nearly 100 presentations in combustion and heat transfer and served as principal investigator for ten Space Shuttle experiments investigating the spread of fire in reduced gravity. He is a Fellow of the American Society of Mechanical Engineers. While an undergraduate at Purdue, Altenkirch became a member of the Sigma Alpha Epsilon fraternity.
From 1988 to 1995, Altenkirch was professor of mechanical engineering and dean of the College of Engineering at Mississippi State University (MSU). While dean of engineering at MSU, he led the effort to secure National Science Foundation (NSF) funding for the establishment of the MSU Engineering Research Center for Computational Field Simulation in 1990. He also served as professor and chair of mechanical engineering at the University of Kentucky. He served as professor of mechanical and materials engineering and dean of the College of Engineering and Architecture at Washington State University.
He was vice president for research at Mississippi State University. During his tenure as vice president, science and engineering expenditures, as reported to NSF, increased by 75 percent from 1997 to 2001.
|
https://en.wikipedia.org/wiki/Familial
|
Familial may refer to:
Familial (album), a 2010 studio album by Phil Selway
Family, a group of people affiliated by consanguinity, affinity, or co-residence
Family (biology), one of the eight major taxonomic ranks, classified between order and genus
Heredity, passing of genetic traits to offspring
Genetic disorder, more specifically
List of genetic disorders
See also
Family (disambiguation)
|
https://en.wikipedia.org/wiki/Ralph%20Tate
|
Ralph Tate (11 March 1840 – 20 September 1901) was a British-born botanist and geologist, who was later active in Australia.
Early life
Tate was born at Alnwick in Northumberland, the son of Thomas Turner Tate (1807–1888), a teacher of mathematics and science, and his wife Frances (née Hunter). He was nephew to George Tate (1805–1871), naturalist and archaeologist, an active member of the Berwickshire Naturalists' Club. Tate was educated at the Cheltenham Training College and at the Royal School of Mines.
Scientific career
In 1861 Tate was appointed teacher of natural science at the Philosophical Institution in Belfast. There he studied botany, publishing his Flora Belfastiensis in 1863, while also investigating the Cretaceous and Triassic rocks of Antrim, the results of which he presenting to the Geological Society of London. In 1864 Tate was appointed assistant at the museum of that society. In 1866 he wrote three botanical papers, and also published A Plain and Easy Account of the Land and Freshwater Mollusks of Great Britain. In 1867 he went on an exploring expedition to Nicaragua and Venezuela. In 1871 he was appointed to the mining school established by the Cleveland ironmasters first at Darlington and later at Redcar. Here he made a special study of the Lias and its fossils, in conjunction with the Rev. J. F. Blake, the results being published in an important work, The Yorkshire Lias (1876), in which the life-history of the strata was first worked out in detail.
In
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https://en.wikipedia.org/wiki/Four-gradient
|
In differential geometry, the four-gradient (or 4-gradient) is the four-vector analogue of the gradient from vector calculus.
In special relativity and in quantum mechanics, the four-gradient is used to define the properties and relations between the various physical four-vectors and tensors.
Notation
This article uses the metric signature.
SR and GR are abbreviations for special relativity and general relativity respectively.
indicates the speed of light in vacuum.
is the flat spacetime metric of SR.
There are alternate ways of writing four-vector expressions in physics:
The four-vector style can be used: , which is typically more compact and can use vector notation, (such as the inner product "dot"), always using bold uppercase to represent the four-vector, and bold lowercase to represent 3-space vectors, e.g. . Most of the 3-space vector rules have analogues in four-vector mathematics.
The Ricci calculus style can be used: , which uses tensor index notation and is useful for more complicated expressions, especially those involving tensors with more than one index, such as .
The Latin tensor index ranges in and represents a 3-space vector, e.g. .
The Greek tensor index ranges in and represents a 4-vector, e.g. .
In SR physics, one typically uses a concise blend, e.g. , where represents the temporal component and represents the spatial 3-component.
Tensors in SR are typically 4D -tensors, with upper indices and lower indices, with the 4D indicating 4
|
https://en.wikipedia.org/wiki/SIRT
|
SIRT can refer to :
Selective internal radiation therapy for cancer
Serious Incident Response Team, Nova Scotia, Canada
Sirtuin, a class of proteins (enzymes) related to genetics
Staten Island Railway (from abbreviation Staten Island Rapid Transit)
See also
Siirt, a city in Turkey
Sirt, another name for Sirte, a city in Libya
Sirte (disambiguation)
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https://en.wikipedia.org/wiki/Stack%20%28computer%20science%29
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{{safesubst:#invoke:RfD||2=Stack (computer science)|month = October
|day = 15
|year = 2023
|time = 01:09
|timestamp = 20231015010935
|content=
REDIRECT Stack (abstract data type)
}}
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https://en.wikipedia.org/wiki/Wear%20%28disambiguation%29
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Wear is surface erosion or deformation by friction.
Wear may also refer to:
Wearing clothes
Wear (journal), in materials science
Wear (surname), includes a list of people
River Wear, in northeast England
WEAR-TV, a T.V. station in Florida, U.S.
World Engineering Anthropometry Resource, (WEAR), a global non-profit
Wearing ship or jibe, a sailing maneuver
See also
Wear and tear, damage that naturally occurs as a result of use or aging
Wear Valley (disambiguation)
Weare (disambiguation)
Wearing (disambiguation)
Ware (disambiguation)
Wair (disambiguation)
Weir (disambiguation)
Were (disambiguation)
Where (disambiguation)
Whir (disambiguation)
Whirr, an American band
|
https://en.wikipedia.org/wiki/Call%20stack
|
In computer science, a call stack is a stack data structure that stores information about the active subroutines of a computer program. This kind of stack is also known as an execution stack, program stack, control stack, run-time stack, or machine stack, and is often shortened to just "the stack". Although maintenance of the call stack is important for the proper functioning of most software, the details are normally hidden and automatic in high-level programming languages. Many computer instruction sets provide special instructions for manipulating stacks.
A call stack is used for several related purposes, but the main reason for having one is to keep track of the point to which each active subroutine should return control when it finishes executing. An active subroutine is one that has been called, but is yet to complete execution, after which control should be handed back to the point of call. Such activations of subroutines may be nested to any level (recursive as a special case), hence the stack structure. For example, if a subroutine DrawSquare calls a subroutine DrawLine from four different places, DrawLine must know where to return when its execution completes. To accomplish this, the address following the instruction that jumps to DrawLine, the return address, is pushed onto the top of the call stack with each call.
Description
Since the call stack is organized as a stack, the caller pushes the return address onto the stack, and the called subroutine, when it fi
|
https://en.wikipedia.org/wiki/Local%20variable
|
In computer science, a local variable is a variable that is given local scope. A local variable reference in the function or block in which it is declared overrides the same variable name in the larger scope. In programming languages with only two levels of visibility, local variables are contrasted with global variables. On the other hand, many ALGOL-derived languages allow any number of nested levels of visibility, with private variables, functions, constants and types hidden within them, either by nested blocks or nested functions. Local variables are fundamental to procedural programming, and more generally modular programming: variables of local scope are used to avoid issues with side-effects that can occur with global variables.
Scope
Local variables may have a lexical or dynamic scope, though lexical (static) scoping is far more common. In lexical scoping (or lexical scope; also called static scoping or static scope), if a variable name's scope is a certain block, then its scope is the program text of the block definition: within that block's text, the variable name exists, and is bound to the variable's value, but outside that block's text, the variable name does not exist. By contrast, in dynamic scoping (or dynamic scope), if a variable name's scope is a certain block, then its scope is that block and all functions transitively called by that block (except when overridden again by another declaration); after the block ends, the variable name does not exist. Som
|
https://en.wikipedia.org/wiki/Sergei%20Navashin
|
Sergei Gavrilovich Navashin (); (14 December 1857 – 10 December 1930) was a Russian Empire and Soviet biologist. He discovered double fertilization in plants in 1898.
Biography
1874 — enters the Medical Surgical Academy in St. Petersburg, works on chemistry in the laboratory of A. Borodin
1878 — moves to the Moscow University, obtains Candidate degree in 1881 in Biology. Under the influence of K. Timiryazev and V. Zinger starts to study Botany. Receives a position of a laboratory assistant at the chair of Plant Physiology and later (1885) in the Petrovskaya Agricultural Academy.
1894 — is invited to work at the chair of Systematics and Morphology of the Kiev University.
During 1894-1914 works as a director of the Botanical Garden of Kiev University
1896 — defends his doctoral thesis at Odessa University
1918-1923—professor of Tbilisi University (Georgia)
1923—founds the Timiryazev Biological Institute in Moscow. Heads it till 1929.
References
External links
Sergei Gavrilovich Navashin at www.cybertruffle.org.uk
1857 births
1930 deaths
Biologists from the Russian Empire
Soviet biologists
Corresponding members of the Saint Petersburg Academy of Sciences
Full Members of the Russian Academy of Sciences (1917–1925)
Full Members of the USSR Academy of Sciences
Members of the Royal Society of Sciences in Uppsala
Full Members of the All-Ukrainian Academy of Sciences
Russian scientists
|
https://en.wikipedia.org/wiki/Georgii%20Nadson
|
Georgii Adamovich Nadson (, Kiev – April 15, 1939) was a Soviet biologist, "one of the pioneers of radioecology in Russia" He became professor at St. Petersburg University in 1900. In 1930, he founded the Laboratory of Microbiology of the Russian Academy of Sciences (which in 1934 was transferred from Leningrad to Moscow and later transformed into the Institute of Microbiology). He was director of the institute until 1937, when he was "falsely accused of participating in so-called anti-Soviet sabotage and terrorism and arrested" On April 14, 1939, he was found guilty of participation in a terrorist organization, and on the next day he was shot and buried at the Kommunarka shooting ground. The real reason for his execution was his opposition to Lysenkoism.
Ulvella nadsonii, a species of algae, is named for him.
References
I. E. Mishustina. History of Marine Microbiology in Russia (the Soviet Union) in the Second Half of the 20th Century. https://doi.org/10.1023%2FA%3A1025863006270
External links
Georgii Adamovich Nadson at www.cybertruffle.org.uk
1867 births
1939 deaths
Scientists from Kyiv
People from Kievsky Uyezd
Botanists from the Russian Empire
Soviet botanists
Soviet geneticists
Soviet microbiologists
Saint Petersburg State University alumni
Full Members of the USSR Academy of Sciences
Great Purge victims from Ukraine
Soviet rehabilitations
|
https://en.wikipedia.org/wiki/Nikolay%20Timofeev-Ressovsky
|
Nikolaj Vladimirovich Timofeev-Resovskij (also Timofeyeff-Ressovsky; ; – 28 March 1981) was a Soviet biologist. He conducted research in radiation genetics, experimental population genetics, and microevolution. His life was highlighted by scientific achievements in the face of severe personal hardship, including his imprisonment and working in secret scientific facilities of Soviet Gulag.
Timofeev-Ressovsky was a descendant of the old Russian school of scientists, characterised by broad naturalistic views on the world, simultaneously combined with exact analysis of causes and consequences and establishment of elementary phenomena. He widely collaborated with physicists. Known for his influential personality, he was a talented story-teller and teacher.
Education
Nikolaj Vladimirovich Timofeev-Resovski, began his university education from 1916 to 1917 at the Moscow City People's University named after A. L. Shanyavskij. From 1917 to 1922, he studied at the First Moscow State University.
The First World War and the consequences of the Russian Revolution of 1917 interrupted his education for periods of time. At the outbreak of the Russian Civil War, Timofeev-Resovskij was a follower of the anarchist Peter Kropotkin. In 1918, he volunteered to serve in a small anarchist cavalry unit, which was part of the Green army, i.e., they were neither supporters of the Bolshevik Red army nor the White army of General Anton Ivanovich Denikin. Eventually, in 1919, the anarchists joined
|
https://en.wikipedia.org/wiki/Non-perturbative
|
In mathematics and physics, a non-perturbative function or process is one that cannot be described by perturbation theory. An example is the function
which does not have a Taylor series at x = 0. Every coefficient of the Taylor expansion around x = 0 is exactly zero, but the function is non-zero if x ≠ 0.
In physics, such functions arise for phenomena which are impossible to understand by perturbation theory, at any finite order. In quantum field theory, 't Hooft–Polyakov monopoles, domain walls, flux tubes, and instantons are examples. A concrete, physical example is given by the Schwinger effect, whereby a strong electric field may spontaneously decay into electron-positron pairs. For not too strong fields, the rate per unit volume of this process is given by,
which cannot be expanded in a Taylor series in the electric charge , or the electric field strength . Here is the mass of an electron and we have used units where .
In theoretical physics, a non-perturbative solution is one that cannot be described in terms of perturbations about some simple background, such as empty space. For this reason, non-perturbative solutions and theories yield insights into areas and subjects that perturbative methods cannot reveal.
See also
Lattice QCD
Soliton
Sphaleron
Instanton
BCFW recursion
Operator product expansion
Conformal bootstrap
Loop quantum gravity
Causal dynamical triangulation
References
Perturbation theory
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