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https://en.wikipedia.org/wiki/Supplee%27s%20paradox
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In relativistic physics, Supplee's paradox (also called the submarine paradox) is a physical paradox that arises when considering the buoyant force exerted on a relativistic bullet (or in a submarine) immersed in a fluid subject to an ambient gravitational field. If a bullet has neutral buoyancy when it is at rest in a perfect fluid and then it is launched with a relativistic speed, observers at rest within the fluid would conclude that the bullet should sink, since its density will increase due to the length contraction effect. On the other hand, in the bullet's proper frame it is the moving fluid that becomes denser and hence the bullet would float. But the bullet cannot sink in one frame and float in another, so there is a paradox situation.
The paradox was first formulated by James M. Supplee (1989), where a non-rigorous explanation was presented. George Matsas has analysed this paradox in the scope of general relativity and also pointed out that these relativistic buoyancy effects could be important in some questions regarding the thermodynamics of black holes. A comprehensive explanation of Supplee's paradox through both the special and the general theory of relativity was presented by Vieira.
Hrvoje Nikolic noticed that rigidity of the submarine is not essential and presented a general relativistic analysis revealing that paradox resolves by the fact that the relevant velocity of the submarine is relative to Earth (which is the source of the gravitational field), not
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https://en.wikipedia.org/wiki/Computational%20cybernetics
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Computational cybernetics is the integration of cybernetics and computational intelligence techniques. Though the term Cybernetics entered the technical lexicon in the 1940s and 1950s, it was first used informally as a popular noun in the 1960s, when it became associated with computers, robotics, Artificial Intelligence and Science fiction.
The initial promise of cybernetics was that it would revolutionise the mathematical biologies (a blanket term that includes some kinds of AI) by its use of closed loop semantics rather than open loop mathematics to describe and control living systems and biological process behaviours. It is fair to say that this idealistic program goal remains generally unrealised.
While ‘philosophical’ treatments of cybernetics are common, especially in the biosciences, computational cybernetics has failed to gain traction in mainstream engineering and graduate education. This makes its specific achievements all the more remarkable. Feldman and Dyer (independently) discovered the true mechanism of somatic motor governance. This theory, called ‘equilibrium point theory’ by Feldman [1], and ‘neocybernetics’ by Dyer [2] debunks the concept of efference copy completely.
While Cybernetics is primarily concerned with the study of control systems, computational cybernetics focuses on their automatic (complex, autonomic, flexible, adaptive) operation. Furthermore, computational cybernetics covers not only mechanical, but biological (living), social and econom
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https://en.wikipedia.org/wiki/E.%20H.%20Moore
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Eliakim Hastings Moore (; January 26, 1862 – December 30, 1932), usually cited as E. H. Moore or E. Hastings Moore, was an American mathematician.
Life
Moore, the son of a Methodist minister and grandson of US Congressman Eliakim H. Moore, discovered mathematics through a summer job at the Cincinnati Observatory while in high school. He subsequently studied mathematics at Yale University, where he was a member of Skull and Bones and obtained a BA in 1883 and the PhD in 1885 with a thesis supervised by Hubert Anson Newton, on some work of William Kingdon Clifford and Arthur Cayley. Newton encouraged Moore to study in Germany, and thus he spent an academic year at the University of Berlin, attending lectures by Leopold Kronecker and Karl Weierstrass.
On his return to the United States, Moore taught at Yale and at Northwestern University. When the University of Chicago opened its doors in 1892, Moore was the first head of its mathematics department, a position he retained until his death in 1932. His first two colleagues were Oskar Bolza and Heinrich Maschke. The resulting department was the second research-oriented mathematics department in American history, after Johns Hopkins University.
Accomplishments
Moore first worked in abstract algebra, proving in 1893 the classification of the structure of finite fields (also called Galois fields). Around 1900, he began working on the foundations of geometry. He reformulated Hilbert's axioms for geometry so that points were the only
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https://en.wikipedia.org/wiki/List%20of%20geneticists
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This is a list of people who have made notable contributions to genetics. The growth and development of genetics represents the work of many people. This list of geneticists is therefore by no means complete. Contributors of great distinction to genetics are not yet on the list.
A
Dagfinn Aarskog (1928–2014), Norwegian pediatrician and geneticist, described Aarskog–Scott syndrome
Jon Aase (born 1936), US dysmorphologist, described Aase syndrome, expert on fetal alcohol syndrome
John Abelson (born c. 1939), US biochemist, studies of machinery and mechanism of RNA splicing
Susan L. Ackerman, US neurogeneticist, genes controlling brain development and neuron survival
Jerry Adams (born 1940), US molecular biologist in Australia, hematopoietic genetics and cancer
Bruce Alberts (born 1938), US biochemist, phage worker, studied DNA replication and cell division
William Allan (1881–1943), US country doctor, pioneered human genetics
C. David Allis (born 1951), US biologist with a fascination for chromatin
Robin Allshire (born 1960), UK-based Irish molecular biologist/geneticist and expert in formation of heterochromatin and centromeres
Carl-Henry Alström (1907–1993), Swedish psychiatrist, described genetic disease: Alström syndrome
Frederick Alt, American geneticist known for research on maintenance of genome stability in the cells of the mammalian immunological system
Russ Altman, US geneticist and bioengineer known for his work in pharmacogenomics
Sidney Altman (1939–2022), Ca
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https://en.wikipedia.org/wiki/Triplet%20state
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In quantum mechanics, a triplet state, or spin triplet, is the quantum state of an object such as an electron, atom, or molecule, having a quantum spin S = 1. It has three allowed values of the spin's projection along a given axis mS = −1, 0, or +1, giving the name "triplet".
Spin, in the context of quantum mechanics, is not a mechanical rotation but a more abstract concept that characterizes a particle's intrinsic angular momentum. It is particularly important for systems at atomic length scales, such as individual atoms, protons, or electrons.
A triplet state occurs in cases where the spins of two unpaired electrons, each having spin s = 1/2, align to give S = 1, in contrast to the more common case of two electrons aligning oppositely to give S = 0, a spin singlet. Most molecules encountered in daily life exist in a singlet state because all of their electrons are paired, but molecular oxygen is an exception. At room temperature, O2 exists in a triplet state, which can only undergo a chemical reaction by making the forbidden transition into a singlet state. This makes it kinetically nonreactive despite being thermodynamically one of the strongest oxidants. Photochemical or thermal activation can bring it into the singlet state, which makes it kinetically as well as thermodynamically a very strong oxidant.
Two spin-1/2 particles
In a system with two spin-1/2 particlesfor example the proton and electron in the ground state of hydrogenmeasured on a given axis, each parti
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https://en.wikipedia.org/wiki/Photoelasticity
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In materials science, photoelasticity describes changes in the optical properties of a material under mechanical deformation. It is a property of all dielectric media and is often used to experimentally determine the stress distribution in a material.
History
The photoelastic phenomenon was first discovered by the Scottish physicist David Brewster, who immediately recognized it as stress-induced birefringence. That diagnosis was confirmed in a direct refraction experiment by Augustin-Jean Fresnel. Experimental frameworks were developed at the beginning of the twentieth century with the works of E. G. Coker and L. N. G. Filon of University of London. Their book Treatise on Photoelasticity, published in 1930 by Cambridge Press, became a standard text on the subject. Between 1930 and 1940, many other books appeared on the subject, including books in Russian, German and French. Max M. Frocht published the classic two volume work, Photoelasticity, in the field. At the same time, much development occurred in the field – great improvements were achieved in technique, and the equipment was simplified. With refinements in the technology, photoelastic experiments were extended to determining three-dimensional states of stress. In parallel to developments in experimental technique, the first phenomenological description of photoelasticity was given in 1890 by Friedrich Pockels, however this was proved inadequate almost a century later by Nelson & Lax as the description by Pockels only
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https://en.wikipedia.org/wiki/Reactive%20intermediate
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In chemistry, a reactive intermediate or an intermediate is a short-lived, high-energy, highly reactive molecule. When generated in a chemical reaction, it will quickly convert into a more stable molecule. Only in exceptional cases can these compounds be isolated and stored, e.g. low temperatures, matrix isolation. When their existence is indicated, reactive intermediates can help explain how a chemical reaction takes place.
Most chemical reactions take more than one elementary step to complete, and a reactive intermediate is a high-energy, yet stable, product that exists only in one of the intermediate steps. The series of steps together make a reaction mechanism. A reactive intermediate differs from a reactant or product or a simple reaction intermediate only in that it cannot usually be isolated but is sometimes observable only through fast spectroscopic methods. It is stable in the sense that an elementary reaction forms the reactive intermediate and the elementary reaction in the next step is needed to destroy it.
When a reactive intermediate is not observable, its existence must be inferred through experimentation. This usually involves changing reaction conditions such as temperature or concentration and applying the techniques of chemical kinetics, chemical thermodynamics, or spectroscopy. Reactive intermediates based on carbon are radicals, carbenes, carbocations, carbanions, arynes, and carbynes.
Common features
Reactive intermediates have several features in co
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https://en.wikipedia.org/wiki/Cage%20effect
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In chemistry, the cage effect (also known as geminate recombination) describes how the properties of a molecule are affected by its surroundings. First introduced by James Franck and Eugene Rabinowitch in 1934, the cage effect suggests that instead of acting as an individual particle, molecules in solvent are more accurately described as an encapsulated particle. The encapsulated molecules or radicals are called cage pairs or geminate pairs. In order to interact with other molecules, the caged particle must diffuse from its solvent cage. The typical lifetime of a solvent cage is 10 seconds. Many manifestations of the cage effect exist.
In free radical polymerization, radicals formed from the decomposition of an initiator molecule are surrounded by a cage consisting of solvent and/or monomer molecules. Within the cage, the free radicals undergo many collisions leading to their recombination or mutual deactivation. This can be described by the following reaction:
After recombination, free radicals can either react with monomer molecules within the cage walls or diffuse out of the cage. In polymers, the probability of a free radical pair to escape recombination in the cage is 0.1 – 0.01 and 0.3-0.8 in liquids. In unimolecular chemistry, geminate recombination has first been studied in the solution phase using iodine molecules and heme proteins. In the solid state, geminate recombination has been demonstrated with small molecules trapped in noble gas solid matrices and in tri
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https://en.wikipedia.org/wiki/Interval%20tree
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In computer science, an interval tree is a tree data structure to hold intervals. Specifically, it allows one to efficiently find all intervals that overlap with any given interval or point. It is often used for windowing queries, for instance, to find all roads on a computerized map inside a rectangular viewport, or to find all visible elements inside a three-dimensional scene. A similar data structure is the segment tree.
The trivial solution is to visit each interval and test whether it intersects the given point or interval, which requires time, where is the number of intervals in the collection. Since a query may return all intervals, for example if the query is a large interval intersecting all intervals in the collection, this is asymptotically optimal; however, we can do better by considering output-sensitive algorithms, where the runtime is expressed in terms of , the number of intervals produced by the query. Interval trees have a query time of and an initial creation time of , while limiting memory consumption to . After creation, interval trees may be dynamic, allowing efficient insertion and deletion of an interval in time. If the endpoints of intervals are within a small integer range (e.g., in the range ), faster and in fact optimal data structures exist with preprocessing time and query time for reporting intervals containing a given query point (see for a very simple one).
Naive approach
In a simple case, the intervals do not overlap and they can be
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https://en.wikipedia.org/wiki/Maria%20McRae
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Maria McRae (born c. 1966 in Sudbury, Ontario) is a lawyer and politician. She represented the River Ward on Ottawa City Council, covering some of the city's southern suburbs. Born in Sudbury, Ontario McRae has an undergraduate degree in biology and a law degree from the University of Western Ontario. She moved to Ottawa in 2000 working as a legal consultant and teaching at Algonquin College. In the 2003 Ottawa election ran to replace the departing Wendy Stewart. McRae, who was endorsed by Stewart, won a large victory against two opponents in the November 10 election. She was re-elected in 2010, but announced that she would not run again in 2014. On council, she was considered a centrist. She lives in the Hunt Club area with her husband, Paul.
First mandate
She ran on a fiscally conservative platform opposing tax hikes and voted against a tax increase the first year, but faced with the significant budget shortfall she was forced to abandon this pledge. She also was criticized for paying Stewart $4000 in consulting fees.
On November 9, 2005, McRae did not vote in favour of a pesticide bylaw that was promoted by the Canadian Cancer Society and the Children's Hospital of Eastern Ontario (CHEO). In the period leading up to the vote, McRae was implicated in email incident. It was the daughter of a woman retired federal intelligence analyst who discovered McRae's wrongdoing, when the daughter received an acknowledgement from Councillor Cullen on which the content of her pro-by
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https://en.wikipedia.org/wiki/Univalent%20function
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In mathematics, in the branch of complex analysis, a holomorphic function on an open subset of the complex plane is called univalent if it is injective.
Examples
The function is univalent in the open unit disc, as implies that . As the second factor is non-zero in the open unit disc, must be injective.
Basic properties
One can prove that if and are two open connected sets in the complex plane, and
is a univalent function such that (that is, is surjective), then the derivative of is never zero, is invertible, and its inverse is also holomorphic. More, one has by the chain rule
for all in
Comparison with real functions
For real analytic functions, unlike for complex analytic (that is, holomorphic) functions, these statements fail to hold. For example, consider the function
given by ƒ(x) = x3. This function is clearly injective, but its derivative is 0 at x = 0, and its inverse is not analytic, or even differentiable, on the whole interval (−1, 1). Consequently, if we enlarge the domain to an open subset G of the complex plane, it must fail to be injective; and this is the case, since (for example) f(εω) = f(ε) (where ω is a primitive cube root of unity and ε is a positive real number smaller than the radius of G as a neighbourhood of 0).
See also
Biholomorphic mapping
De Branges's theorem
Koebe quarter theorem
Riemann mapping theorem
Schlicht function
Note
References
Analytic functions
is:Eintæk vörpun
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https://en.wikipedia.org/wiki/Parity%20anomaly
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In theoretical physics a quantum field theory is said to have a parity anomaly if its classical action is invariant under a change of parity of the universe, but the quantum theory is not invariant.
This kind of anomaly can occur in odd-dimensional gauge theories with fermions whose gauge groups have odd dual Coxeter numbers. They were first introduced by Antti J. Niemi and Gordon Walter Semenoff in the letter Axial-Anomaly-Induced Fermion Fractionization and Effective Gauge-Theory Actions in Odd-Dimensional Space-Times and by A. Norman Redlich in the letter Gauge Noninvariance and Parity Nonconservation of Three-Dimensional Fermions and the article Parity violation and gauge noninvariance of the effective gauge field action in three dimensions. It is in some sense an odd-dimensional version of Edward Witten's SU(2) anomaly in 4-dimensions, and in fact Redlich writes that his demonstration follows Witten's.
The anomaly in 3-dimensions
Consider a classically parity-invariant gauge theory whose gauge group G has dual Coxeter number h in 3-dimensions. Include n Majorana fermions which transform under a real representation of G. This theory naively suffers from an ultraviolet divergence. If one includes a gauge-invariant regulator then the quantum parity invariance of the theory will be broken if h and n are odd.
Sketch of the demonstration
The anomaly can only be a choice of sign
Consider for example Pauli–Villars regularization. One needs to add n massive Majorana
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https://en.wikipedia.org/wiki/Hartry%20Field
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Hartry H. Field (born November 30, 1946) is an American philosopher. He is Silver Professor of Philosophy at New York University; he is a notable contributor to philosophy of science, philosophy of mathematics, epistemology, and philosophy of mind.
Early life and education
Hartry Hamlin Field was born on November 30, 1946 in Boston, Massachusetts to Adelaide () and Donald Field. Field earned a B.A. in mathematics from the University of Wisconsin–Madison in 1967 and an M.A. in philosophy from Harvard University in 1968. He earned his Ph.D. in philosophy from Harvard in 1972 under the direction of Hilary Putnam and Richard Boyd.
Academic career
He taught first at Princeton University, and then at the University of Southern California and City University of New York Graduate Center before joining the NYU faculty in 1997, where he is currently Silver Professor of Philosophy.
Field was elected Fellow of the American Academy of Arts and Sciences in 2003 and is also a past winner of the Lakatos Prize in 1986. He delivered the 2008 John Locke Lectures at the University of Oxford. In 2012, he was appointed Distinguished Research Professor at the University of Birmingham in the UK.
Philosophical work
Field's first work was a commentary on Alfred Tarski's theory of truth, which he has worked on since 1972. His current view on this matter is in favor of a deflationary theory of truth. His most influential work produced in this period is probably "Theory Change and the Indeterminacy
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https://en.wikipedia.org/wiki/MSCE
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MSCE can mean:
Master of Science in Civil Engineering; see Civil engineering
Master of Science in Clinical Epidemiology
Master of Science in Communications Engineering; see Telecommunications engineering
Master of Science in Computer Engineering; see Computer Engineering
Mobility and Supply Chain Engineering
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https://en.wikipedia.org/wiki/Newton%20da%20Costa
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Newton Carneiro Affonso da Costa (born 16 September 1929 in Curitiba, Brazil) is a Brazilian mathematician, logician, and philosopher. He studied engineering and mathematics at the Federal University of Paraná in Curitiba and the title of his 1961 Ph.D. dissertation was Topological spaces and continuous functions.
Work
Paraconsistency
Da Costa's international recognition came especially through his work on paraconsistent logic and its application to various fields such as philosophy, law, computing, and artificial intelligence. He is one of the founders of this non-classical logic. In addition, he constructed the theory of quasi-truth that constitutes a generalization of Alfred Tarski's theory of truth, and applied it to the foundations of science.
Other fields; foundations of physics
The scope of his research also includes model theory, generalized Galois theory, axiomatic foundations of quantum theory and relativity, complexity theory, and abstract logics. Da Costa has significantly contributed to the philosophy of logic, paraconsistent modal logics, ontology, and philosophy of science. He served as the President of the Brazilian Association of Logic and the Director of the Institute of Mathematics at the University of São Paulo. He received many awards and held numerous visiting scholarships at universities and centers of research in all continents.
Da Costa and physicist Francisco Antônio Dória axiomatized large portions of classical physics with the help of Patrick
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https://en.wikipedia.org/wiki/Intercellular%20adhesion%20molecule
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In molecular biology, intercellular adhesion molecules (ICAMs) and vascular cell adhesion molecule-1 (VCAM-1) are part of the immunoglobulin superfamily. They are important in inflammation, immune responses and in intracellular signalling events. The ICAM family consists of five members, designated ICAM-1 to ICAM-5. They are known to bind to leucocyte integrins CD11/CD18 such as LFA-1 and Macrophage-1 antigen, during inflammation and in immune responses. In addition, ICAMs may exist in soluble forms in human plasma, due to activation and proteolysis mechanisms at cell surfaces.
Mammalian intercellular adhesion molecules include:
ICAM-1
ICAM2
ICAM3
ICAM4
ICAM5
References
Cell biology
Protein families
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https://en.wikipedia.org/wiki/Complex%20vector%20bundle
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In mathematics, a complex vector bundle is a vector bundle whose fibers are complex vector spaces.
Any complex vector bundle can be viewed as a real vector bundle through the restriction of scalars. Conversely, any real vector bundle E can be promoted to a complex vector bundle, the complexification
whose fibers are Ex ⊗R C.
Any complex vector bundle over a paracompact space admits a hermitian metric.
The basic invariant of a complex vector bundle is a Chern class. A complex vector bundle is canonically oriented; in particular, one can take its Euler class.
A complex vector bundle is a holomorphic vector bundle if X is a complex manifold and if the local trivializations are biholomorphic.
Complex structure
A complex vector bundle can be thought of as a real vector bundle with an additional structure, the complex structure. By definition, a complex structure is a bundle map between a real vector bundle E and itself:
such that J acts as the square root i of −1 on fibers: if is the map on fiber-level, then as a linear map. If E is a complex vector bundle, then the complex structure J can be defined by setting to be the scalar multiplication by . Conversely, if E is a real vector bundle with a complex structure J, then E can be turned into a complex vector bundle by setting: for any real numbers a, b and a real vector v in a fiber Ex,
Example: A complex structure on the tangent bundle of a real manifold M is usually called an almost complex structure. A theorem of Ne
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https://en.wikipedia.org/wiki/List%20of%20National%20Medal%20of%20Science%20laureates
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The National Medal of Science is an honor bestowed by the President of the United States to individuals in science and engineering who have made important contributions to the advancement of knowledge in the following six fields: behavioral and social sciences, biology, chemistry, engineering, mathematics and physical sciences. The Committee on the National Medal of Science under the National Science Foundation (NSF) is responsible for recommending medal candidates to the President.
Behavioral and Social Science
1964—Neal Elgar Miller
1986—Herbert A. Simon
1987—Anne Anastasi, George J. Stigler
1988—Milton Friedman
1990—Leonid Hurwicz, Patrick Suppes
1991—George A. Miller
1992—Eleanor J. Gibson
1994—Robert K. Merton
1995—Roger N. Shepard
1996—Paul A. Samuelson
1997—William K. Estes
1998—William Julius Wilson
1999—Robert M. Solow
2000—Gary S. Becker
2003—R. Duncan Luce
2004—Kenneth J. Arrow
2005—Gordon H. Bower
2008—Michael I. Posner
2009—Mortimer Mishkin
2011—Anne Treisman
2012—Robert Axelrod
2014—Albert Bandura
Biological Sciences
1963—Cornelius Van Niel
1964—Theodosius Dobzhansky, Marshall W. Nirenberg
1965—Francis Peyton Rous, George G. Simpson, Donald D. Van Slyke
1966—Edward F. Knipling, Fritz Albert Lipmann, William C. Rose, Sewall Wright
1967—Kenneth S. Cole, Harry F. Harlow, Michael Heidelberger, Alfred Sturtevant
1968—Horace Barker, Bernard B. Brodie, Detlev W. Bronk, Jay Lush, Burrhus Frederic Skinner
1969—Robert J. Huebner, Ernst Mayr
1970—Barbara McClintock, Albe
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https://en.wikipedia.org/wiki/Nonsymmetric%20gravitational%20theory
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In theoretical physics, the nonsymmetric gravitational theory (NGT) of John Moffat is a classical theory of gravitation that tries to explain the observation of the flat rotation curves of galaxies.
In general relativity, the gravitational field is characterized by a symmetric rank-2 tensor, the metric tensor. The possibility of generalizing the metric tensor has been considered by many, including Albert Einstein and others. A general (nonsymmetric) tensor can always be decomposed into a symmetric and an antisymmetric part. As the electromagnetic field is characterized by an antisymmetric rank-2 tensor, there is an obvious possibility for a unified theory: a nonsymmetric tensor composed of a symmetric part representing gravity, and an antisymmetric part that represents electromagnetism. Research in this direction ultimately proved fruitless; the desired classical unified field theory was not found.
In 1979, Moffat made the observation that the antisymmetric part of the generalized metric tensor need not necessarily represent electromagnetism; it may represent a new, hypothetical force. Later, in 1995, Moffat noted that the field corresponding with the antisymmetric part need not be massless, like the electromagnetic (or gravitational) fields.
In its original form, the theory may be unstable, although this has only been shown in the case of the linearized version.
In the weak field approximation where interaction between fields is not taken into account, NGT is characteriz
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https://en.wikipedia.org/wiki/Bart%20Selman
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Bart Selman is a Dutch-American professor of computer science at Cornell University. He has previously worked at AT&T Bell Laboratories. He is also co-founder and principal investigator of the Center for Human-Compatible Artificial Intelligence (CHAI) at the University of California, Berkeley, led by Berkeley artificial intelligence (AI) expert Stuart J. Russell, and co-chair of the Computing Community Consortium's 20-year roadmap for AI research.
Education and career
Selman attended the Technical University of Delft, from where he received a master's degree in physics, graduating in 1983. He received his master's and PhD in computer science from the University of Toronto in 1985 and 1991 respectively.
Research
Selman's research focuses on the increasing and changing role of machines and computing in society. His studies at Center for Human-Compatible AI (CHAI) focus on the potential risks and negative impacts of advanced AI. An expert in AI Safety, he studies how computing has shifted from ethics-neutral software to predictive algorithms and advocates integrating ethics and AI.
He has authored over 90 publications, which have appeared in journals including Nature, Science, and Proceedings of the National Academy of Sciences. He has presented at several conferences in the fields of artificial intelligence and computer science.
His research concepts include tractable inference, knowledge representation, stochastic search methods, theory approximation, knowledge compilati
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https://en.wikipedia.org/wiki/Robert%20Ochsenfeld
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Robert Ochsenfeld (18 May 1901 – 5 December 1993) was a German physicist. In 1933 he discovered together with Walther Meissner the Meisner-Ochsenfeld effect.
Born in Helberhausen, Germany, Ochsenfeld studied physics at the Philipps University of Marburg. The subject of his PhD was the study of ferromagnetism. In 1932-1933 he worked at the Physikalisch-Technische Reichsanstalt (PTR) in Berlin in the low temperature group headed by Meissner. Leaving the PTR, he taught at the National Political Institutes of Education in Potsdam until 1940, followed by research for new weapons in World War II.
After the war, he worked until retirement in the Physikalisch-Technische Bundesanstalt (PTB), the successor of the PTR with focus on magnetic materials.
References
External links
1901 births
1993 deaths
People from Hilchenbach
20th-century German physicists
Scientists from the Province of Westphalia
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https://en.wikipedia.org/wiki/OLG
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The acronym OLG may refer to:
Oberlandesgericht, a higher regional court of appeals in Germany
Online gaming
Ontario Lottery and Gaming Corporation, a Canadian provincial government agency which operates lottery games and casinos.
Our Lady of Guadalupe
Overlapping gene in genomes
Overlapping generations in population genetics
Overlapping generations model in economics
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https://en.wikipedia.org/wiki/Nitrene
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In chemistry, a nitrene or imene () is the nitrogen analogue of a carbene. The nitrogen atom is uncharged and univalent, so it has only 6 electrons in its valence level—two covalent bonded and four non-bonded electrons. It is therefore considered an electrophile due to the unsatisfied octet. A nitrene is a reactive intermediate and is involved in many chemical reactions. The simplest nitrene, HN, is called imidogen, and that term is sometimes used as a synonym for the nitrene class.
Electron configuration
In the simplest case, the linear N–H molecule (imidogen) has its nitrogen atom sp hybridized, with two of its four non-bonded electrons as a lone pair in an sp orbital and the other two occupying a degenerate pair of p orbitals. The electron configuration is consistent with Hund's rule: the low energy form is a triplet with one electron in each of the p orbitals and the high energy form is the singlet with an electron pair filling one p orbital and the other p orbital vacant.
As with carbenes, a strong correlation exists between the spin density on the nitrogen atom which can be calculated in silico and the zero-field splitting parameter D which can be derived experimentally from electron spin resonance. Small nitrenes such as NH or CF3N have D values around 1.8 cm−1 with spin densities close to a maximum value of 2. At the lower end of the scale are molecules with low D (< 0.4) values and spin density of 1.2 to 1.4 such as 9-anthrylnitrene and 9-phenanthrylnitrene.
Forma
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https://en.wikipedia.org/wiki/Smooth%20structure
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In mathematics, a smooth structure on a manifold allows for an unambiguous notion of smooth function. In particular, a smooth structure allows one to perform mathematical analysis on the manifold.
Definition
A smooth structure on a manifold is a collection of smoothly equivalent smooth atlases. Here, a smooth atlas for a topological manifold is an atlas for such that each transition function is a smooth map, and two smooth atlases for are smoothly equivalent provided their union is again a smooth atlas for This gives a natural equivalence relation on the set of smooth atlases.
A smooth manifold is a topological manifold together with a smooth structure on
Maximal smooth atlases
By taking the union of all atlases belonging to a smooth structure, we obtain a maximal smooth atlas. This atlas contains every chart that is compatible with the smooth structure. There is a natural one-to-one correspondence between smooth structures and maximal smooth atlases.
Thus, we may regard a smooth structure as a maximal smooth atlas and vice versa.
In general, computations with the maximal atlas of a manifold are rather unwieldy. For most applications, it suffices to choose a smaller atlas.
For example, if the manifold is compact, then one can find an atlas with only finitely many charts.
Equivalence of smooth structures
Let and be two maximal atlases on The two smooth structures associated to and are said to be equivalent if there is a diffeomorphism such that
Ex
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https://en.wikipedia.org/wiki/Darboux%27s%20theorem
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In differential geometry, a field in mathematics, Darboux's theorem is a theorem providing a normal form for special classes of differential 1-forms, partially generalizing the Frobenius integration theorem. It is named after Jean Gaston Darboux who established it as the solution of the Pfaff problem.
It is a foundational result in several fields, the chief among them being symplectic geometry. Indeed, one of its many consequences is that any two symplectic manifolds of the same dimension are locally symplectomorphic to one another. That is, every -dimensional symplectic manifold can be made to look locally like the linear symplectic space with its canonical symplectic form.
There is also an analogous consequence of the theorem applied to contact geometry.
Statement
Suppose that is a differential 1-form on an -dimensional manifold, such that has constant rank . Then
if everywhere, then there is a local system of coordinates in which
if everywhere, then there is a local system of coordinates in which
Darboux's original proof used induction on and it can be equivalently presented in terms of distributions or of differential ideals.
Frobenius' theorem
Darboux's theorem for ensures the any 1-form such that can be written as in some coordinate system .
This recovers one of the formulation of Frobenius theorem in terms of differential forms: if is the differential ideal generated by , then implies the existence of a coordinate system where is actually gen
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https://en.wikipedia.org/wiki/Compactification%20%28physics%29
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In theoretical physics, compactification means changing a theory with respect to one of its space-time dimensions. Instead of having a theory with this dimension being infinite, one changes the theory so that this dimension has a finite length, and may also be periodic.
Compactification plays an important part in thermal field theory where one compactifies time, in string theory where one compactifies the extra dimensions of the theory, and in two- or one-dimensional solid state physics, where one considers a system which is limited in one of the three usual spatial dimensions.
At the limit where the size of the compact dimension goes to zero, no fields depend on this extra dimension, and the theory is dimensionally reduced.
In string theory
In string theory, compactification is a generalization of Kaluza–Klein theory. It tries to reconcile the gap between the conception of our universe based on its four observable dimensions with the ten, eleven, or twenty-six dimensions which theoretical equations lead us to suppose the universe is made with.
For this purpose it is assumed the extra dimensions are "wrapped" up on themselves, or "curled" up on Calabi–Yau spaces, or on orbifolds. Models in which the compact directions support fluxes are known as flux compactifications. The coupling constant of string theory, which determines the probability of strings splitting and reconnecting, can be described by a field called a dilaton. This in turn can be described as the size of an
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https://en.wikipedia.org/wiki/Compactification
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Compactification may refer to:
Compactification (mathematics), making a topological space compact
Compactification (physics), the "curling up" of extra dimensions in string theory
See also
Compaction (disambiguation)
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https://en.wikipedia.org/wiki/Matrix%20norm
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In mathematics, a matrix norm is a vector norm in a vector space whose elements (vectors) are matrices (of given dimensions).
Preliminaries
Given a field of either real or complex numbers, let be the -vector space of matrices with rows and columns and entries in the field . A matrix norm is a norm on .
This article will always write such norms with double vertical bars (like so: ). Thus, the matrix norm is a function that must satisfy the following properties:
For all scalars and matrices ,
(positive-valued)
(definite)
(absolutely homogeneous)
(sub-additive or satisfying the triangle inequality)
The only feature distinguishing matrices from rearranged vectors is multiplication. Matrix norms are particularly useful if they are also sub-multiplicative:
Every norm on can be rescaled to be sub-multiplicative; in some books, the terminology matrix norm is reserved for sub-multiplicative norms.
Matrix norms induced by vector norms
Suppose a vector norm on and a vector norm on are given. Any matrix induces a linear operator from to with respect to the standard basis, and one defines the corresponding induced norm or operator norm or subordinate norm on the space of all matrices as follows:
where denotes the supremum. This norm measures how much the mapping induced by can stretch vectors.
Depending on the vector norms , used, notation other than can be used for the operator norm.
Matrix norms induced by vector p-norms
If the p-norm for vectors (
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https://en.wikipedia.org/wiki/Phase%20response
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In signal processing, phase response is the relationship between the phase of a sinusoidal input and the output signal passing through any device that accepts input and produces an output signal, such as an amplifier or a filter.
Amplifiers, filters, and other devices are often categorized by their amplitude and/or phase response. The amplitude response is the ratio of output amplitude to input, usually a function of the frequency. Similarly, phase response is the phase of the output with the input as reference. The input is defined as zero phase. A phase response is not limited to lying between 0° and 360°, as phase can accumulate to any amount of time.
See also
Group delay and phase delay
References
Trigonometry
Wave mechanics
Signal processing
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https://en.wikipedia.org/wiki/Mercury%20coulometer
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In electrochemistry, a mercury coulometer is an analytical instrument which uses mercury to perform coulometry (determining the amount of matter transformed in a chemical reaction by measuring electric current) on the following reaction:
These oxidation/reduction processes have 100% efficiency with the wide range of the current densities. Measuring of the quantity of electricity (coulombs) is based on the changes of the mass of the mercury electrode. Mass of the electrode can be increased during cathodic deposition of the mercury ions or decreased during the anodic dissolution of the metal.
where is the quantity of electricity; are the mass changes; is the Faraday constant; and is the molar mass of mercury.
Construction
This coulometer has different constructions but all of them are based on mass measurements. The device consists of two reservoirs connected by a thin graduated capillary tube containing a solution of the mercury(II)-ions. Each of the reservoirs has an electrode immersed in a drop of mercury. Another small drop of mercury is inserted into the capillary. When the current is turned on, it initiates dissolution of the metallic mercury on one side of the drop in the capillary and deposition on the other side of the same drop. This drop starts to move. Because of the high efficiency of the deposition/dissolution of the mercury under the current influence, the mass or volume of this small drop is constant and its movement is linearly correlated with the passe
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https://en.wikipedia.org/wiki/Franz%20von%20Paula%20Schrank
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Franz von Paula Schrank (21 August 1747, in Vornbach – 22 December 1835) was a German priest, botanist and entomologist.
Biography
He was ordained as a priest in Vienna in 1784, gaining his doctorate in theology two years later. In 1786 he was named chair of mathematics and physics at the lyceum in Amberg, and in 1784 became a professor of botany and zoology at the University of Ingolstadt (later removed to Landshut). Schrank was the first director of the botanical gardens in Munich from 1809 to 1832.
Schrank was the first author to use the genus name Triops, which he used in his work on the fauna of Bavaria in 1803.
Works
Beiträge zur Naturgeschichte (Augsburg, 1776)
Vorlesungen über die Art die Naturgeschichte zu studieren (Ratisbohn, 1780)
Enumeratio insectorum Austriæ indigenorum (Wien, 1781)
Anleitung die Naturgeschichte zu studieren (München, 1783)
Naturhistorische Briefe über Österreich, Salzburg, Passau und Berchtesgaden with Karl Maria Erenbert Freiherr von Moll, Salzburg, 1784–1785)
Anfangsgründe der Botanik (München, 1785)
Baiersche Reise … (1786)
Verzeichnis der bisher hinlänglich bekannten Eingeweidewürmer, nebst einer Abhandlungen über ihre Anverwandschaften (München, 1787)
Bayerische Flora (München, 1789)
Primitiæ floræ salisburgensis, cum dissertatione prævia de discrimine plantarum ab animalibus (Frankfurt, 1792)
Abhandlungen einer Privatgesellschaft vom Naturforschern und Ökonomen in Oberteutschland (München, 1792)
Anfangsgründe der Bergwerks
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https://en.wikipedia.org/wiki/A.%20Ross%20Eckler%20Jr.
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Albert Ross Eckler Jr. (August 29, 1927 – December 9, 2016) was an American logologist, statistician, and author, the son of statistician A. Ross Eckler. He served in the US Army from 1946 – 1947. He received a BA from Swarthmore College with High Honors in 1950 and a PhD in mathematics from Princeton University in 1954.
Biography
While at Bell Labs (1954–1984), Eckler co-authored Mathematical Models of Target Coverage and Missile Allocation with Stefan A. Burr.
Eckler was the publisher and editor of Word Ways: The Journal of Recreational Linguistics. In 1996 he published a book on logology entitled Making the Alphabet Dance. Recreational Wordplay.
He was also the author of The National Puzzlers' League, The First 115 Years, a history of the National Puzzlers' League (NPL). He and his wife Faith were married for more than 50 years, and were former NPL editors under the collective pen name "Faro" (with variant forms "FAro" for Faith and "faRO" for Ross).
Eckler's hobbies were genealogy and supercentenarian research. Eckler disproved exaggerated age claims such as those of Charlie Smith and George Fruits while authenticating others such as Delina Filkins (1815–1928). He was an avid hiker, leading hikes for the Appalachian Mountain Club between 1978 and 1997, a member (and trail maintainer) of the New York–New Jersey Trail Conference and researched portions of the Lawrence Line starting in 1996. He was also an active recreational caver starting in 1952; he joined the Natio
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https://en.wikipedia.org/wiki/Nanosocialism
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Nanosocialism refers generally to a set of economic theories of social organization advocating state or collective ownership and administration of the research, development and use of nanotechnology.
Politics
Nanosocialism is a stance that favors participatory politics to guide state intervention in the effort to manage the transition to a society revolutionized by molecular nanotechnology.
"Nanosocialism" is a term coined by David M. Berube, the associate director of Nanoscience and Technology Studies at the USC NanoCenter, who argues that nanotechnological projections need to be tempered by technorealism about the implications of nanotechnology in a technocapitalist society, but that its applications also offer enormous opportunities for economic abundance and social progress.
In popular culture
In the role-playing game Transhuman Space, nanosocialism is described as a descendant of "infosocialism", in which intellectual property is nationalized and freely distributed by the state. It is adopted by some developing nations to counter the hold corporations from wealthier nations have on copyrights and patents. This fictional version of nanosocialism was coined by David L. Pulver, the game's creator, who was unaware that the term had already been used by Berube.
See also
Post-scarcity economy
References
Socialism
Political neologisms
Technology neologisms
Technology in society
Nanotechnology
Political science terminology
Technological utopianism
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https://en.wikipedia.org/wiki/RSA%20problem
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In cryptography, the RSA problem summarizes the task of performing an RSA private-key operation given only the public key. The RSA algorithm raises a message to an exponent, modulo a composite number N whose factors are not known. Thus, the task can be neatly described as finding the eth roots of an arbitrary number, modulo N. For large RSA key sizes (in excess of 1024 bits), no efficient method for solving this problem is known; if an efficient method is ever developed, it would threaten the current or eventual security of RSA-based cryptosystems—both for public-key encryption and digital signatures.
More specifically, the RSA problem is to efficiently compute P given an RSA public key (N, e) and a ciphertext C ≡ P e (mod N). The structure of the RSA public key requires that N be a large semiprime (i.e., a product of two large prime numbers), that 2 < e < N, that e be coprime to φ(N), and that 0 ≤ C < N. C is chosen randomly within that range; to specify the problem with complete precision, one must also specify how N and e are generated, which will depend on the precise means of RSA random keypair generation in use.
The most efficient method known to solve the RSA problem is by first factoring the modulus N, a task believed to be impractical if N is sufficiently large (see integer factorization). The RSA key setup routine already turns the public exponent e, with this prime factorization, into the private exponent d, and so exactly the same algorithm allows anyone who f
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https://en.wikipedia.org/wiki/PRP
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PRP may refer to:
Places
People's Republic of Poland, 1952-1990
Pleasure Ridge Park, Louisville, in Kentucky, United States
Preston Park railway station, in Sussex, England
Medicine and biology
Panretinal photocoagulation, a treatment for proliferative diabetic retinopathy
Penicillin-resistant pneumococci, a Streptococcus species resistant to antibiotics
Pityriasis rubra pilaris, a rare skin disorder
Platelet-rich plasma
Prion protein, a major constituent of the infectious prion
Progressive rubella panencephalitis, a viral neurological disorder
Proline rich proteins, a class of intrinsically unstructured proteins
Psychological refractory period, a period between processing multiple stimuli
Mathematics and science
Probable prime, a number that satisfies some requirements for prime numbers
Parallel Redundancy Protocol, a network protocol providing fault tolerance
Pseudorandom permutation, a class of functions in cryptography
Petroleum Remediation Product, a substance for cleaning petroleum-based pollution
Organizations
Press Recognition Panel, a UK body relating to the recognition of press regulators
Peel Regional Police, in Ontario, Canada
Park Royal Partnership, an industrial partnership in London
Puerto Rico Police
Political parties
Praja Rajyam Party, in India between 2008-2011
Progressive Reform Party (South Africa), between 1975-1977
Portuguese Republican Party, between 1876-1911
Progressive Reform Party (Suriname), in South America
Patriotic
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https://en.wikipedia.org/wiki/Wahlund%20effect
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In population genetics, the Wahlund effect is a reduction of heterozygosity (that is when an organism has two different alleles at a locus) in a population caused by subpopulation structure. Namely, if two or more subpopulations are in a Hardy–Weinberg equilibrium but have different allele frequencies, the overall heterozygosity is reduced compared to if the whole population was in equilibrium. The underlying causes of this population subdivision could be geographic barriers to gene flow followed by genetic drift in the subpopulations.
The Wahlund effect was first described by the Swedish geneticist Sten Wahlund in 1928.
Simplest example
Suppose there is a population , with allele frequencies of A and a given by and respectively (). Suppose this population is split into two equally-sized subpopulations, and , and that all the A alleles are in subpopulation and all the a alleles are in subpopulation (this could occur due to drift). Then, there are no heterozygotes, even though the subpopulations are in a Hardy–Weinberg equilibrium.
Case of two alleles and two subpopulations
To make a slight generalization of the above example, let and represent the allele frequencies of A in and , respectively (and and likewise represent a).
Let the allele frequency in each population be different, i.e. .
Suppose each population is in an internal Hardy–Weinberg equilibrium, so that the genotype frequencies AA, Aa and aa are p2, 2pq, and q2 respectively for each population.
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https://en.wikipedia.org/wiki/Gustave%20Mal%C3%A9cot
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Gustave Malécot (28 December 1911 – November 1998) was a French mathematician whose work on heredity had a strong influence on population genetics.
Biography
Malécot grew up in L'Horme, a small village near St. Étienne in the Loire département, the son of a mine engineer.
In 1935, Malécot obtained a degree in mathematics from the École Normale Supérieure, Paris. He then went on to do a PhD under George Darmois and completed that in 1939. His work focused on R.A. Fisher's 1918 article The Correlation Between Relatives on the Supposition of Mendelian Inheritance.
Between 1940 and 1942, with France under Nazi German occupation, Malécot taught mathematics at the Lyceé de Saint-Étienne. In 1942 he was appointed maître de conférence (lecturer) Université de Montpellier. In 1945 he joined the Université de Lyon, becoming professor of applied mathematics in 1946, a position he held until his retirement in 1981.
Malécot's Coancestry Coefficient, a measure of genetic similarity, still bears his name.
Bibliography
Gustave Malécot, The mathematics of heredity, Freeman & Co 1969, (translated from the French edition, 1948)
References
Epperson, Bryan K. (1999). Gustave Malécot, 1911–1998: Population Genetics Founding Father. Genetics 152, 477-484. link to article
Nagylaki, Thomas (1989). Gustave Malécot and the transition from classical to modern population genetics. Genetics 122, 253–268. link to article
Slatkin, Montgomery & Veuille, Michel (Eds.) (2002). Modern developmen
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https://en.wikipedia.org/wiki/Van%20Wijngaarden%20grammar
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In computer science, a Van Wijngaarden grammar (also vW-grammar or W-grammar) is a formalism for defining formal languages. The name derives from the formalism invented by Adriaan van Wijngaarden
for the purpose of defining the ALGOL 68 programming language.
The resulting specification remains its most notable application.
Van Wijngaarden grammars address the problem that context-free grammars cannot express agreement or reference, where two different parts of the sentence must agree with each other in some way. For example, the sentence "The birds was eating" is not Standard English because it fails to agree on number. A context-free grammar would parse "The birds was eating" and "The birds were eating" and "The bird was eating" in the same way. However, context-free grammars have the benefit of simplicity whereas van Wijngaarden grammars are considered highly complex.
Two levels
W-grammars are two-level grammars: they are defined by a pair of grammars, that operate on different levels:
the hypergrammar is an attribute grammar, i.e. a set of context-free grammar rules in which the nonterminals may have attributes; and
the metagrammar is a context-free grammar defining possible values for these attributes.
The set of strings generated by a W-grammar is defined by a two-stage process:
within each hyperrule, for each attribute that occurs in it, pick a value for it generated by the metagrammar; the result is a normal context-free grammar rule; do this in every possible w
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https://en.wikipedia.org/wiki/Chemical%20trap
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In chemistry, a chemical trap is a chemical compound that is used to detect unstable compounds. The method relies on efficiency of bimolecular reactions with reagents to produce a more easily characterize trapped product. In some cases, the trapping agent is used in large excess.
Case studies
Cyclobutadiene
A famous example is the detection of cyclobutadiene released upon oxidation of cyclobutadieneiron tricarbonyl. When this degradation is conducted in the presence of an alkyne, the cyclobutadiene is trapped as a bicyclohexadiene. The requirement for this trapping experiment is that the oxidant (ceric ammonium nitrate) and the trapping agent be mutually compatible.
Diphosphorus
Diphosphorus is an old target of chemists since it is the heavy analogue of N2. Its fleeting existence is inferred by the controlled degradation of certain niobium complexes in the presence of trapping agents. Again, a Diels-Alder strategy is employed in the trapping:
Silylene
Another classic but elusive family of targets are silylenes, analogues of carbenes. It was proposed that dechlorination of dimethyldichlorosilane generates dimethylsilylene:
SiCl2(CH3)2 + 2 K → Si(CH3)2 + 2 KCl
This inference is supported by conducting the dechlorination in the presence of trimethylsilane, the trapped product being pentamethyldisilane:
Si(CH3)2 + HSi(CH3)3 → (CH3)2Si(H)-Si(CH3)3
Not that the trapping agent does not react with dimethyldichlorosilane or potassium metal.
Related meanings
In some ca
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https://en.wikipedia.org/wiki/Herman%20Cain
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Herman Cain (December 13, 1945July 30, 2020) was an American businessman and Tea Party movement activist in the Republican Party. Born in Memphis, Tennessee, Cain grew up in Georgia and graduated from Morehouse College with a bachelor's degree in mathematics. He then earned a master's degree in computer science at Purdue University while also working full-time for the U.S. Department of the Navy. In 1977, he joined the Pillsbury Company where he later became vice president. During the 1980s, Cain's success as a business executive at Burger King prompted Pillsbury to appoint him as chairman and CEO of Godfather's Pizza, in which capacity he served from 1986 to 1996.
Cain was chairman of the Federal Reserve Bank of Kansas City Omaha Branch from 1989 to 1991. He was deputy chairman, from 1992 to 1994, and then chairman until 1996, of the Federal Reserve Bank of Kansas City. In 1995, he was appointed to the Kemp Commission and, in 1996, he served as a senior economic adviser to Bob Dole's presidential campaign. From 1996 to 1999, Cain served as president and CEO of the National Restaurant Association.
In May 2011, Cain announced his 2012 presidential candidacy. By the fall, his proposed 9–9–9 tax plan and debating performances had made him a serious contender for the Republican nomination. In November, however, Cain was accused of sexual harassment by multiple women. Cain denied the allegations, but announced the suspension of his campaign on December 3. He remained active in t
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https://en.wikipedia.org/wiki/Genotype%20frequency
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Genetic variation in populations can be analyzed and quantified by the frequency of alleles. Two fundamental calculations are central to population genetics: allele frequencies and genotype frequencies. Genotype frequency in a population is the number of individuals with a given genotype divided by the total number of individuals in the population.
In population genetics, the genotype frequency is the frequency or proportion (i.e., 0 < f < 1) of genotypes in a population.
Although allele and genotype frequencies are related, it is important to clearly distinguish them.
Genotype frequency may also be used in the future (for "genomic profiling") to predict someone's having a disease or even a birth defect. It can also be used to determine ethnic diversity.
Genotype frequencies may be represented by a De Finetti diagram.
Numerical example
As an example, consider a population of 100 four-o-'clock plants (Mirabilis jalapa) with the following genotypes:
49 red-flowered plants with the genotype AA
42 pink-flowered plants with genotype Aa
9 white-flowered plants with genotype aa
When calculating an allele frequency for a diploid species, remember that homozygous individuals have two copies of an allele, whereas heterozygotes have only one. In our example, each of the 42 pink-flowered heterozygotes has one copy of the a allele, and each of the 9 white-flowered homozygotes has two copies. Therefore, the allele frequency for a (the white color allele) equals
This r
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https://en.wikipedia.org/wiki/Subgroup%20series
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In mathematics, specifically group theory, a subgroup series of a group is a chain of subgroups:
where is the trivial subgroup. Subgroup series can simplify the study of a group to the study of simpler subgroups and their relations, and several subgroup series can be invariantly defined and are important invariants of groups. A subgroup series is used in the subgroup method.
Subgroup series are a special example of the use of filtrations in abstract algebra.
Definition
Normal series, subnormal series
A subnormal series (also normal series, normal tower, subinvariant series, or just series) of a group G is a sequence of subgroups, each a normal subgroup of the next one. In a standard notation
There is no requirement made that Ai be a normal subgroup of G, only a normal subgroup of Ai +1. The quotient groups Ai +1/Ai are called the factor groups of the series.
If in addition each Ai is normal in G, then the series is called a normal series, when this term is not used for the weaker sense, or an invariant series.
Length
A series with the additional property that Ai ≠ Ai +1 for all i is called a series without repetition; equivalently, each Ai is a proper subgroup of Ai +1. The length of a series is the number of strict inclusions Ai < Ai +1. If the series has no repetition then the length is n.
For a subnormal series, the length is the number of non-trivial factor groups. Every nontrivial group has a normal series of length 1, namely , and any nontrivial proper norma
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https://en.wikipedia.org/wiki/Nanoruler
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A nanoruler is a ruler of tiny proportions, made of a silicon crystal lattice structure. Since it can accurately measure fractions of nanometers, it could help standardize the future nanotechnology industry. Since the characteristics of silicon are well understood, the distance between one crystal lattice line to another is well known. Therefore, counting these lines can reveal a fairly accurate measurement.
The ruler was developed by the National Institute of Standards and Technology, and unveiled in 2005.
Nanoruler also is the name of a machine to produce large (greater than 300 mm x 300 mm) grating patterns with nanometer precision, based on the principle of Scanning Beam Interference Lithography. Instead of the traditional technique to produce gratings through mechanical ruling, this approach rules gratings through the interference of light beams. The Nanoruler was developed in the Space Nanotechnology Laboratory of the Kavli Institute for Astrophysics and Space Research at the Massachusetts Institute of Technology.
References
Nanotechnology
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https://en.wikipedia.org/wiki/Placement%20exam
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A placement exam or placement test is a test designed to evaluate a person's preexisting knowledge of a subject and thus determine the level most suitable for the person to begin coursework on that subject.
In many countries, including the United States, it is not unusual for students to take a placement exam in a subject such as mathematics upon entering middle or high school to determine what level of classes they should take. Typically, students are then placed on a tracking system determined by the class they are approved to enter—for example, if a student takes music theory to students whose knowledge in that area is more advanced than what a typical entering freshman's would be in those subjects. Scores on such exams as the Advanced Placement, International Baccalaureate, SAT Subject Tests, and British Advanced Level exams can also serve as placement tests for students in certain subjects, where a high score would enable them to get into a more advanced class than what a freshman would normally take.
References
School examinations
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https://en.wikipedia.org/wiki/Hatchling
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In oviparous biology, a hatchling is a newly hatched fish, amphibian, reptile, or bird. A group of mammals called monotremes lay eggs, and their young are hatchlings as well.
Fish
Fish hatchlings generally do not receive parental care, similar to reptiles. Like reptiles, fish hatchlings can be affected by xenobiotic compounds. For example, exposure to xenoestrogens can feminize fish. As well, hatchlings raised in water with high levels of carbon dioxide demonstrate unusual behaviour, such as being attracted to the scent of predators. This change could be reversed by immersion into gabazine water, leading to the hypothesis that acidic waters affect hatchling brain chemistry.
Amphibians
The behavior of an amphibian hatchling, commonly referred to as a tadpole, is controlled by a few thousand neurons. 99% of a Xenopus hatchling's first day after hatching is spent hanging from a thread of mucus secreted from near its mouth will eventually form; if it becomes detached from this thread, it will swim back and become reattached, usually within ten seconds. While newt hatchlings are only able to swim for a few seconds, Xenopus tadpoles may be able to swim for minutes as long as they do not bump into anything. The tadpole live from remaining yolk-mass in the gut for a period, before it swims off to find food.
Reptiles
The reptile hatchling is quite the opposite of an altricial bird hatchling. Most hatchling reptiles are born with the same instincts as their parents and leave to li
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https://en.wikipedia.org/wiki/Breather
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In physics, a breather is a nonlinear wave in which energy concentrates in a localized and oscillatory fashion. This contradicts with the expectations derived from the corresponding linear system for infinitesimal amplitudes, which tends towards an even distribution of initially localized energy.
A discrete breather is a breather solution on a nonlinear lattice.
The term breather originates from the characteristic that most breathers are localized in space and oscillate (breathe) in time. But also the opposite situation: oscillations in space and localized in time, is denoted as a breather.
Overview
A breather is a localized periodic solution of either continuous media equations or discrete lattice equations. The exactly solvable sine-Gordon equation and the focusing nonlinear Schrödinger equation are examples of one-dimensional partial differential equations that possess breather solutions. Discrete nonlinear Hamiltonian lattices in many cases support breather solutions.
Breathers are solitonic structures. There are two types of breathers: standing or traveling ones. Standing breathers correspond to localized solutions whose amplitude vary in time (they are sometimes called oscillons). A necessary condition for the existence of breathers in discrete lattices is that the breather main frequency and all its multipliers are located outside of the phonon spectrum of the lattice.
Example of a breather solution for the sine-Gordon equation
The sine-Gordon equation is the no
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https://en.wikipedia.org/wiki/Henri%20Schwery
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Henri Schwery (14 June 1932 – 7 January 2021) was a Swiss prelate of the Catholic Church who was Bishop of Sion from 1977 to 1995. He was raised to the rank of cardinal in 1991.
Early life and ordination
Born in St-Léonard, Valais, Schwery studied mathematics, theoretical physics, Catholic theology, and philosophy in Sion, Rome, and Fribourg. On 7 July 1957 he was ordained a priest.
Professor and bishop
From 1961 to 1977, Schwery was part of the theological faculty of Sion, which he headed from 1972 to 1977.
Pope Paul VI appointed Schwery the Bishop of Sion on 22 July 1977. On 17 September 1977, he was consecrated a bishop by his predecessor as Bishop of Sion, François-Nestor Adam. He was president of the Swiss Bishops Conference from 1983 to 1988.
In his diocese in June 1988, Archbishop Marcel Lefebvre consecrated four bishops without papal approval. Schwery called for church unity in the face of that schism.
Cardinal
On 28 June 1991, Pope John Paul II named Schwery a member of the College of Cardinals, assigning him as a cardinal-priest to Santi Protomartiri a Via Aurelia Antica. On 25 July 1991, Pope John Paul made him a member of the Congregation for Divine Worship and the Congregation for the Clergy.
During March of that year, he paid his respects when Lefebvre died, making a quiet visit to pray over his body alongside the Apostolic Nuncio to Switzerland Edoardo Rovida.
Pope John Paul accepted his resignation as Bishop of Sion on 1 April 1995 when he was 62. He ha
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https://en.wikipedia.org/wiki/Wang%20Xiaoyun
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Wang Xiaoyun (; born 1966) is a Chinese cryptographer, mathematician, and computer scientist. She is a professor in the Department of Mathematics and System Science of Shandong University and an academician of the Chinese Academy of Sciences.
Early life and education
Wang was born in Zhucheng, Shandong Province. She gained bachelor (1987), master (1990) and doctorate (1993) degrees at Shandong University, and subsequently lectured in the mathematics department from 1993. Her doctoral advisor was Pan Chengdong. Wang was appointed assistant professor in 1995, and full professor in 2001. She became the Chen Ning Yang Professor of the Center for Advanced Study, Tsinghua University in 2005.
Career and research
At the rump session of CRYPTO 2004, she and co-authors demonstrated collision attacks against MD5, SHA-0 and other related hash functions (a collision occurs when two distinct messages result in the same hash function output). They received a standing ovation for their work.
In February 2005, it was reported that Wang and co-authors Yiqun Lisa Yin and Hongbo Yu had found a method to find collisions in the SHA-1 hash function, which is used in many of today's mainstream security products. Their attack is estimated to require less than 269 operations, far fewer than the 280 operations previously thought needed to find a collision in . Their work was published at the CRYPTO '05 conference. In August 2005, an improved attack on SHA-1, discovered by Wang, Andrew Yao and Fran
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https://en.wikipedia.org/wiki/Abdal
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Abdāl () lit: substitutes, but which can also mean "generous" [karīm] and "noble" [sharīf]) is a term used in Islamic metaphysics and Islamic mysticism, both Sunni and Shiite, to refer to a particularly important group of God's saints. In the tradition of Sunni Islam in particular, the concept attained an especially important position in the writings of the Sunni mystics and theologians, whence it appears in the works of Sunni authorities as diverse as Abu Talib al-Makki (d. 956), Ali Hujwiri (d. 1072), Ibn Asakir (d. 1076), Khwaja Abdullah Ansari (d. 1088), Ibn Arabi (d. 1240), and Ibn Khaldun (d. 1406).
It is a rank of forty saints, but more often the larger group of 356 saints in Sufi hagiography. In this theology it is said that they are only known to and appointed by Allah, and it is through their operations that the world continues to exist. The term over time has come to include a greater hierarchy of saints, all of different rank and prestige.
Etymology
"Abdal" is the plural of "Badal" or rather "Badeel", and means "those who get replaced", "those who serve as a partial replacement to the role of the prophets" or "friends of God". The Abdals are the group of true, pure believers in God. They serve God during their lifetime; when they die, they are immediately replaced by another selected by God from a larger group said to be the 500 "Akhyar", i.e., the good ones.
Leadership
The Abdals are headed by their leader, "Al-Ghawth (Sheikh Abdul Qadir Jilani)" ("the Helper"
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https://en.wikipedia.org/wiki/Twisted%20cubic
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In mathematics, a twisted cubic is a smooth, rational curve C of degree three in projective 3-space P3. It is a fundamental example of a skew curve. It is essentially unique, up to projective transformation (the twisted cubic, therefore). In algebraic geometry, the twisted cubic is a simple example of a projective variety that is not linear or a hypersurface, in fact not a complete intersection. It is the three-dimensional case of the rational normal curve, and is the image of a Veronese map of degree three on the projective line.
Definition
The twisted cubic is most easily given parametrically as the image of the map
which assigns to the homogeneous coordinate the value
In one coordinate patch of projective space, the map is simply the moment curve
That is, it is the closure by a single point at infinity of the affine curve .
The twisted cubic is a projective variety, defined as the intersection of three quadrics. In homogeneous coordinates on P3, the twisted cubic is the closed subscheme defined by the vanishing of the three homogeneous polynomials
It may be checked that these three quadratic forms vanish identically when using the explicit parameterization above; that is, substitute x3 for X, and so on.
More strongly, the homogeneous ideal of the twisted cubic C is generated by these three homogeneous polynomials of degree 2.
Properties
The twisted cubic has the following properties:
It is the set-theoretic complete intersection of and , but not a scheme-theor
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https://en.wikipedia.org/wiki/Population%20size
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In population genetics and population ecology, population size (usually denoted N) is a countable quantity representing the number of individual organisms in a population. Population size is directly associated with amount of genetic drift, and is the underlying cause of effects like population bottlenecks and the founder effect. Genetic drift is the major source of decrease of genetic diversity within populations which drives fixation and can potentially lead to speciation events.
Genetic drift
Of the five conditions required to maintain Hardy-Weinberg Equilibrium, infinite population size will always be violated; this means that some degree of genetic drift is always occurring. Smaller population size leads to increased genetic drift, it has been hypothesized that this gives these groups an evolutionary advantage for acquisition of genome complexity. An alternate hypothesis posits that while genetic drift plays a larger role in small populations developing complexity, selection is the mechanism by which large populations develop complexity.
Population bottlenecks and founder effect
Population bottlenecks occur when population size reduces for a short period of time, decreasing the genetic diversity in the population.
The founder effect occurs when few individuals from a larger population establish a new population and also decreases the genetic diversity, and was originally outlined by Ernst Mayr. The founder effect is a unique case of genetic drift, as the smaller fou
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https://en.wikipedia.org/wiki/Injective%20sheaf
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In mathematics, injective sheaves of abelian groups are used to construct the resolutions needed to define sheaf cohomology (and other derived functors, such as sheaf Ext).
There is a further group of related concepts applied to sheaves: flabby (flasque in French), fine, soft (mou in French), acyclic. In the history of the subject they were introduced before the 1957 "Tohoku paper" of Alexander Grothendieck, which showed that the abelian category notion of injective object sufficed to found the theory. The other classes of sheaves are historically older notions. The abstract framework for defining cohomology and derived functors does not need them. However, in most concrete situations, resolutions by acyclic sheaves are often easier to construct. Acyclic sheaves therefore serve for computational purposes, for example the Leray spectral sequence.
Injective sheaves
An injective sheaf is a sheaf that is an injective object of the category of abelian sheaves; in other words, homomorphisms from to can always be extended to any sheaf containing
The category of abelian sheaves has enough injective objects: this means that any sheaf is a subsheaf of an injective sheaf. This result of Grothendieck follows from the existence of a generator of the category (it can be written down explicitly, and is related to the subobject classifier). This is enough to show that right derived functors of any left exact functor exist and are unique up to canonical isomorphism.
For technical pur
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https://en.wikipedia.org/wiki/Cuisenaire%20rods
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Cuisenaire rods are mathematics learning aids for students that provide an interactive, hands-on way to explore mathematics and learn mathematical concepts, such as the four basic arithmetical operations, working with fractions and finding divisors. In the early 1950s, Caleb Gattegno popularised this set of coloured number rods created by Georges Cuisenaire (1891–1975), a Belgian primary school teacher, who called the rods réglettes.
According to Gattegno, "Georges Cuisenaire showed in the early 1950s that students who had been taught traditionally, and were rated 'weak', took huge strides when they shifted to using the material. They became 'very good' at traditional arithmetic when they were allowed to manipulate the rods."
History
The educationalists Maria Montessori and Friedrich Fröbel had used rods to represent numbers, but it was Georges Cuisenaire who introduced the rods that were to be used across the world from the 1950s onwards. In 1952 he published Les nombres en couleurs, Numbers in Color, which outlined their use. Cuisenaire, a violin player, taught music as well as arithmetic in the primary school in Thuin. He wondered why children found it easy and enjoyable to pick up a tune and yet found mathematics neither easy nor enjoyable. These comparisons with music and its representation led Cuisenaire to experiment in 1931 with a set of ten rods sawn out of wood, with lengths from 1 cm to 10 cm. He painted each length of rod a different colour and began to use thes
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https://en.wikipedia.org/wiki/Linear%20complex%20structure
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In mathematics, a complex structure on a real vector space V is an automorphism of V that squares to the minus identity, −I. Such a structure on V allows one to define multiplication by complex scalars in a canonical fashion so as to regard V as a complex vector space.
Every complex vector space can be equipped with a compatible complex structure, however, there is in general no canonical such structure. Complex structures have applications in representation theory as well as in complex geometry where they play an essential role in the definition of almost complex manifolds, by contrast to complex manifolds. The term "complex structure" often refers to this structure on manifolds; when it refers instead to a structure on vector spaces, it may be called a linear complex structure.
Definition and properties
A complex structure on a real vector space V is a real linear transformation
such that
Here means composed with itself and is the identity map on . That is, the effect of applying twice is the same as multiplication by . This is reminiscent of multiplication by the imaginary unit, . A complex structure allows one to endow with the structure of a complex vector space. Complex scalar multiplication can be defined by
for all real numbers and all vectors in . One can check that this does, in fact, give the structure of a complex vector space which we denote .
Going in the other direction, if one starts with a complex vector space then one can define a complex st
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https://en.wikipedia.org/wiki/136%20%28number%29
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136 (one hundred [and] thirty-six) is the natural number following 135 and preceding 137.
In mathematics
136 is itself a factor of the Eddington number. With a total of 8 divisors, 8 among them, 136 is a refactorable number. It is a composite number.
136 is a centered triangular number and a centered nonagonal number.
The sum of the ninth row of Lozanić's triangle is 136.
136 is a self-descriptive number in base 4, and a repdigit in base 16. In base 10, the sum of the cubes of its digits is . The sum of the cubes of the digits of 244 is .
136 is a triangular number, because it's the sum of the first 16 positive integers.
In the military
Force 136 branch of the British organization, the Special Operations Executive (SOE), in the South-East Asian Theatre of World War II
USNS Mission Soledad (T-AO-136) was a United States Navy Mission Buenaventura-class fleet oiler during World War II
USS Admirable (AM-136) was a United States Navy Admirable class minesweeper
USS Ara (AK-136) was a United States Navy during World War II
was a United States Navy during World War II
USS Botetourt (APA-136) was a United States Navy during World War II and the Korean War
was a United States Navy tanker during World War II
was a United States Navy during World War II
was a United States Navy heavy cruiser during World War II
USS Frederick C. Davis (DE-136) was a United States Navy during World War II
was a United States Navy General G. O. Squier-class transport ship during
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https://en.wikipedia.org/wiki/173%20%28number%29
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173 (one hundred [and] seventy-three) is the natural number following 172 and preceding 174.
In mathematics
173 is:
an odd number.
a deficient number.
an odious number.
a balanced prime.
an Eisenstein prime with no imaginary part.
a Sophie Germain prime.
an inconsummate number.
the sum of 2 squares: 22 + 132.
the sum of three consecutive prime numbers: 53 + 59 + 61.
Palindromic number in bases 3 (201023) and 9 (2129).
In astronomy
173 Ino is a large dark main belt asteroid
173P/Mueller is a periodic comet in the Solar System
Arp 173 (VV 296, KPG 439) is a pair of galaxies in the constellation Boötes
In the military
173rd Air Refueling Squadron unit of the Nebraska Air National Guard
173rd Airborne Brigade Combat Team of the United States Army based in Vicenza
173rd Battalion unit of the Canadian Expeditionary Force during the World War I
173rd Special Operations Aviation Squadron of the Australian Army
K-173 Chelyabinsk Russian
was a U.S. Navy Phoenix-class auxiliary ship following World War II
was a U.S. Navy during World War II
was a U.S. Navy during World War II
was a U.S. Navy during World War II
was a U.S. Navy yacht during World War I
was a U.S. Navy ship during World War II
was a U.S. Navy submarine chaser during World War II
was a U.S. Navy Porpoise-class submarine during World War II
was a U.S. Navy following World War II
Vought V-173 (Flying Pancake) was a U.S. Navy experimental test aircraft during World War II
In transportati
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https://en.wikipedia.org/wiki/Minimum%20viable%20population
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Minimum viable population (MVP) is a lower bound on the population of a species, such that it can survive in the wild. This term is commonly used in the fields of biology, ecology, and conservation biology. MVP refers to the smallest possible size at which a biological population can exist without facing extinction from natural disasters or demographic, environmental, or genetic stochasticity. The term "population" is defined as a group of interbreeding individuals in similar geographic area that undergo negligible gene flow with other groups of the species. Typically, MVP is used to refer to a wild population, but can also be used for ex-situ conservation (Zoo populations).
Estimation
There is no unique definition of what constitutes a sufficient population for the continuation of a species, because whether a species survives will depend to some extent on random events. Thus, any calculation of a minimum viable population (MVP) will depend on the population projection model used. A set of random (stochastic) projections might be used to estimate the initial population size needed (based on the assumptions in the model) for there to be, (for example) a 95% or 99% probability of survival 1,000 years into the future. Some models use generations as a unit of time rather than years in order to maintain consistency between taxa. These projections (population viability analyses, or PVA) use computer simulations to model populations using demographic and environmental information
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https://en.wikipedia.org/wiki/Carbon-based
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Carbon-based may refer to:
Biology
based on Carbon
Carbon-based life
Carbon chauvinism
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https://en.wikipedia.org/wiki/N.%20G.%20W.%20H.%20Beeger
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Nicolaas George Wijnand Henri Beeger (1884, in Utrecht – 1965, in Amsterdam) was a Dutch mathematician. His 1916 doctorate was on Dirichlet series. He worked for most of his life as a teacher, working on mathematics papers in his spare evenings. After his retirement as a teacher at 65, he began corresponding with many contemporary mathematicians and dedicated himself to his work. Tilburg University still hold biennial lectures entitled the Beeger lectures in his honour.
He is known for having proved that 3511 is a Wieferich prime in 1922 and for introducing the term Carmichael number in 1950.
Works
(N. G. W. H. Beeger ed.), Jakob Philipp Kulik, Luigi Poletti, R. J. Porter, Liste des nombres premiers du onzième million: (plus précisément de 10.006.741 à 10.999.997), Association française pour l'avancement des sciences, Ed. "Werto,", 1951
References
External links
Tilburg University information
1884 births
1965 deaths
Politicians from Utrecht (city)
20th-century Dutch mathematicians
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https://en.wikipedia.org/wiki/Philosophy%20of%20biology
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The philosophy of biology is a subfield of philosophy of science, which deals with epistemological, metaphysical, and ethical issues in the biological and biomedical sciences. Although philosophers of science and philosophers generally have long been interested in biology (e.g., Aristotle, Descartes, and Kant), philosophy of biology only emerged as an independent field of philosophy in the 1960s and 1970s, associated with the research of David Hull. Philosophers of science then began paying increasing attention to biology, from the rise of Neodarwinism in the 1930s and 1940s to the discovery of the structure of DNA in 1953 to more recent advances in genetic engineering.
Other key ideas include the reduction of all life processes to biochemical reactions, and the incorporation of psychology into a broader neuroscience.
Overview
Philosophers of biology examine the practices, theories, and concepts of biologists with a view toward better understanding biology as a scientific discipline (or group of scientific fields). Scientific ideas are philosophically analyzed and their consequences are explored. Philosophers of biology have also explored how our understanding of biology relates to epistemology, ethics, aesthetics, and metaphysics and whether progress in biology should compel modern societies to rethink traditional values concerning all aspects of human life. It is sometimes difficult to separate the philosophy of biology from theoretical biology.
"What is a biological sp
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https://en.wikipedia.org/wiki/Absorption%20band
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In quantum mechanics, an absorption band is a range of wavelengths, frequencies or energies in the electromagnetic spectrum that are characteristic of a particular transition from initial to final state in a substance.
According to quantum mechanics, atoms and molecules can only hold certain defined quantities of energy, or exist in specific states. When such quanta of electromagnetic radiation are emitted or absorbed by an atom or molecule, energy of the radiation changes the state of the atom or molecule from an initial state to a final state.
Overview
According to quantum mechanics, atoms and molecules can only hold certain defined quantities of energy, or exist in specific states. When electromagnetic radiation is absorbed by an atom or molecule, the energy of the radiation changes the state of the atom or molecule from an initial state to a final state. The number of states in a specific energy range is discrete for gaseous or diluted systems, with discrete energy levels. Condensed systems, like liquids or solids, have a continuous density of states distribution and often possess continuous energy bands. In order for a substance to change its energy it must do so in a series of "steps" by the absorption of a photon. This absorption process can move a particle, like an electron, from an occupied state to an empty or unoccupied state. It can also move a whole vibrating or rotating system, like a molecule, from one vibrational or rotational state to another or it can crea
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https://en.wikipedia.org/wiki/Samuel%20Horsley
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Samuel Horsley (15 September 1733 – 4 October 1806) was a British churchman, bishop of Rochester from 1793. He was also well versed in physics and mathematics, on which he wrote a number of papers and thus was elected a Fellow of the Royal Society in 1767; and secretary in 1773, but, in consequence of a difference with the president (Sir Joseph Banks) he withdrew in 1784.
Life
He was the son of Rev John Horsley of Newington Butts and his first wife Anne Hamilton, daughter of Rev Prof William Hamilton of Edinburgh and Mary Robertson.
Entering Trinity Hall, Cambridge in 1751, he became LL.B. in 1758 without graduating in arts. In the following year he succeeded his father in the living of Newington Butts in Surrey. In 1768 he attended the son and heir of the 3rd Earl of Aylesford to Oxford as private tutor; and, after receiving through the earl and Bishop of London various minor preferments, which by dispensations he combined with his first living, he was installed in 1781 as archdeacon of St Albans.
Horsley now entered his controversy with Joseph Priestley, who denied that the early Christians held the doctrine of the Trinity. In this fierce debate, Horsley's aim was to lessen the influence which Priestley's name gave to his views, by pointing to (what he claimed were) inaccuracies in his scholarship. Horsley was rewarded by Lord Chancellor Thurlow with a prebendal stall at Gloucester; and in 1788 Thurlow procured his promotion to the see of St David's.
As a bishop, Horsl
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https://en.wikipedia.org/wiki/Science%20Foundation%20Ireland
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Science Foundation Ireland (SFI; ) is the statutory body in Ireland with responsibility for funding oriented basic and applied research in the areas of science, technology, engineering and mathematics (STEM) with a strategic focus. The agency was established in 2003 under the Industrial Development (Science Foundation Ireland) Act 2003 and is run by a board appointed by the Minister for Further and Higher Education, Research, Innovation and Science. SFI is an agency of the Department of Further and Higher Education, Research, Innovation and Science.
Organisation
Remit
Science Foundation Ireland (SFI) is the national foundation for investment in scientific and engineering research. SFI invests in academic researchers and research teams who are most likely to generate new knowledge, leading edge technologies and competitive enterprises in the fields of science, technology, engineering and maths (STEM).
The foundation also promotes and supports the study of, education in, and engagement with STEM and promotes an awareness and understanding of the value of STEM to society and, in particular, to the growth of the economy.
SFI makes grants based upon the merit review of distinguished scientists.
SFI also facilitates co-operative efforts among education, government, and industry that support its fields of emphasis and promotes Ireland's ensuing achievements around the world.
When applying to SFI, applicants will be asked to justify the alignment of their research with Call- or P
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https://en.wikipedia.org/wiki/Ken%20Perlin
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Kenneth H. Perlin is a professor in the Department of Computer Science at New York University, founding director of the Media Research Lab at NYU, director of the Future Reality Lab at NYU, and the Director of the Games for Learning Institute. He holds a BA. degree in Theoretical Mathematics from Harvard University (7/1979), a MS degree in Computer Science from the Courant Institute of Mathematical Sciences, New York University (6/1984), and a PhD degree in Computer Science from the same institution (2/1986). His research interests include graphics, animation, multimedia, and science education. He developed or was involved with the development of techniques such as Perlin noise, real-time interactive character animation, and computer-user interfaces. He is best known for the development of Perlin noise and Simplex noise, both of which are algorithms for realistic-looking Gradient noise.
He is a collaborator of the World Building Institute.
Awards
In 1996, K. Perlin received an Academy Award for Technical Achievement from the Academy of Motion Picture Arts and Sciences, for the development of Perlin noise. He had introduced this technique with the goal to produce natural-appearing textures on computer-generated surfaces for motion picture visual effects, while working on the Walt Disney Productions' 1982 feature film TRON for which he had developed a large part of the software.
See also
Perlin noise
Quikwriting
Simplex noise
References
External links
Ken Perlin's NYU home
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https://en.wikipedia.org/wiki/CAMS
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CAMS or cams may refer to:
Organizations
Chinese Academy of Medical Sciences
California Academy of Mathematics and Science, a high school in Carson, California, US
Calexico Mission School, a Seventh-day Adventist Church school, California, US
Center for Advanced Media Studies, Johns Hopkins University
Chantiers Aéro-Maritimes de la Seine, a French aircraft manufacturer of the 1920s and 1930s
Coalition Against Militarism in Our Schools in the United States
Copernicus Atmosphere Monitoring Service (CAMS)
Motorsport Australia, formerly the Confederation of Australian Motor Sport, the national sporting organisation vested with the authority to conduct motor sport in Australia by the FIA
Cameras for All-Sky Meteor Surveillance, a project from the SETI Institute that tracks meteor showers globally
Other uses
Camshafts, which can be found on Internal combustion engines
Spring-loaded camming device or cams, a piece of rock climbing or mountaineering protection equipment
Cell adhesion molecules
See also
Cam (disambiguation)
Child and Adolescent Mental Health Services (CAMHS)
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https://en.wikipedia.org/wiki/Chamfer
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A chamfer or is a transitional edge between two faces of an object. Sometimes defined as a form of bevel, it is often created at a 45° angle between two adjoining right-angled faces.
Chamfers are frequently used in machining, carpentry, furniture, concrete formwork, mirrors, and to facilitate assembly of many mechanical engineering designs.
Terminology
In machining the word bevel is not used to refer to a chamfer. Machinists use chamfers to "ease" otherwise sharp edges, both for safety and to prevent damage to the edges.
A chamfer may sometimes be regarded as a type of bevel, and the terms are often used interchangeably.
In furniture-making, a lark's tongue is a chamfer which ends short of a piece in a gradual outward curve, leaving the remainder of the edge as a right angle. Chamfers may be formed in either inside or outside adjoining faces of an object or room.
By comparison, a fillet is the rounding-off of an interior corner, and a round (or radius) the rounding of an outside one.
Carpentry and furniture
Chamfers are used in furniture such as counters and table tops to ease their edges to keep people from bruising themselves in the otherwise sharp corner. When the edges are rounded instead, they are called bullnosed. Special tools such as chamfer mills and chamfer planes are sometimes used.
Architecture
Chamfers are commonly used in architecture, both for functional and aesthetic reasons. For example, the base of the Taj Mahal is a cube with chamfered corners
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https://en.wikipedia.org/wiki/Cornell%20University%20College%20of%20Engineering
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The College of Engineering is a division of Cornell University that was founded in 1870 as the Sibley College of Mechanical Engineering and Mechanic Arts. It is one of four private undergraduate colleges at Cornell that are not statutory colleges.
It currently grants bachelors, masters, and doctoral degrees in a variety of engineering and applied science fields, and is the third largest undergraduate college at Cornell by student enrollment. The college offers over 450 engineering courses, and has an annual research budget exceeding US$112 million.
History
The College of Engineering was founded in 1870 as the Sibley College of Mechanical Engineering and Mechanic Arts. The program was housed in Sibley Hall on what has since become the Arts Quad, both of which are named for Hiram Sibley, the original benefactor whose contributions were used to establish the program. The college took its current name in 1919 when the Sibley College merged with the College of Civil Engineering. It was housed in Sibley, Lincoln, Franklin, Rand, and Morse Halls. In the 1950s the college moved to the southern end of Cornell's campus.
The college is known for a number of firsts. In 1889, the college took over electrical engineering from the Department of Physics, establishing the first department in the United States in this field. The college awarded the nation's first doctorates in both electrical engineering and industrial engineering. The Department of Computer Science, established in 1965 jo
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https://en.wikipedia.org/wiki/Gibbs
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Gibbs or GIBBS is a surname and acronym. It may refer to:
People
Gibbs (surname)
Places
Gibbs (crater), on the Moon
Gibbs, Missouri, US
Gibbs, Tennessee, US
Gibbs Island (South Shetland Islands), Antarctica
2937 Gibbs, an asteroid
Science
Mathematics and statistics
Gibbs phenomenon
Gibbs' inequality
Gibbs sampling
Physics
Gibbs phase rule
Gibbs free energy
Gibbs entropy
Gibbs paradox
Gibbs–Helmholtz equation
Gibbs algorithm
Gibbs state
Gibbs-Marangoni effect
Gibbs phenomenon, an MRI artifact
Organisations
Gibbs & Cox naval architecture firm
Gothenburg International Bioscience Business School
Gibbs College, several US locations
Gibbs Technologies, developer and manufacturer of amphibious vehicles
Gibbs High School (disambiguation), several schools of this name exist
Antony Gibbs & Sons, British trading company, established in London in 1802
Other uses
Gibbs SR, former name of the toothpaste Mentadent
Gibbs Stadium, Spartanburg, South Carolina, US
See also
Gibbs' Reflective Cycle
List of things named after Josiah W. Gibbs
Gibbes (disambiguation)
Gibb (disambiguation)
Gib (disambiguation)
Gipps (disambiguation)
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https://en.wikipedia.org/wiki/Locant
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In the nomenclature of organic chemistry, a locant is a term to indicate the position of a functional group or substituent within a molecule.
Numeric locants
The International Union of Pure and Applied Chemistry (IUPAC) recommends the use of numeric prefixes to indicate the position of substituents, generally by identifying the parent hydrocarbon chain and assigning the carbon atoms based on their substituents in order of precedence. For example, there are at least two isomers of the linear form of pentanone, a ketone that contains a chain of exactly five carbon atoms. There is an oxygen atom bonded to one of the middle three carbons (if it were bonded to an end carbon, the molecule would be an aldehyde, not a ketone), but it is not clear where it is located.
In this example, the carbon atoms are numbered from one to five, which starts at one end and proceeds sequentially along the chain. Now the position of the oxygen atom can be defined as on carbon atom number two, three or four. However, atoms two and four are exactly equivalent - which can be shown by turning the molecule around by 180 degrees.
The locant is the number of the carbon atom to which the oxygen atom is bonded. If the oxygen is bonded to the middle carbon, the locant is 3. If the oxygen is bonded to an atom on either side (adjacent to an end carbon), the locant is 2 or 4; given the choice here, where the carbons are exactly equivalent, the lower number is always chosen. So the locant is either 2 or 3 in
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https://en.wikipedia.org/wiki/De%20Finetti%20diagram
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A de Finetti diagram is a ternary plot used in population genetics. It is named after the Italian statistician Bruno de Finetti (1906–1985) and is used to graph the genotype frequencies of populations, where there are two alleles and the population is diploid. It is based on an equilateral triangle, and Viviani's theorem: the sum of the perpendicular distances from any interior point to the sides of said triangle is a constant equal to the length of the triangle's altitude.
Applications in genetics
The de Finetti diagram is used extensively in A.W.F. Edwards' book Foundations of Mathematical Genetics. The sum of the lengths, representing allele frequencies, is set to be 1. In its simplest form the diagram can be used to show the range of genotype frequencies for which Hardy–Weinberg equilibrium is satisfied (the curve within the diagram). A. W. F. Edwards and Chris Cannings extended its use to demonstrate the changes that occur in allele frequencies under natural selection.
See also
Ternary diagram
Wahlund effect
References
Cannings C., Edwards A. W. F. (1968) "Natural selection and the de Finetti diagram" Ann Hum Gen 31:421–428
Edwards, A.W.F. (2000) Foundations of Mathematical Genetics 2nd Edition, Cambridge University Press.
External links
Online plotting of de Finetti diagrams for population genetics (also calculates Hardy Weinberg equilibrium statistics)
Population genetics
Diagrams
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https://en.wikipedia.org/wiki/Polyol
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In organic chemistry, a polyol is an organic compound containing multiple hydroxyl groups (). The term "polyol" can have slightly different meanings depending on whether it is used in food science or polymer chemistry. Polyols containing two, three and four hydroxyl groups are diols, triols, and tetrols, respectively.
Classification
Polyols may be classified according to their chemistry. Some of these chemistries are polyether, polyester, polycarbonate and also acrylic polyols. Polyether polyols may be further subdivided and classified as polyethylene oxide or polyethylene glycol (PEG), polypropylene glycol (PPG) and Polytetrahydrofuran or PTMEG. These have 2, 3 and 4 carbons respectively per oxygen atom in the repeat unit. Polycaprolactone polyols are also commercially available. There is also an increasing trend to use biobased (and hence renewable) polyols.
Uses
Polyether polyols have numerous uses. As an example, polyurethane foam is a big user of polyether polyols.
Polyester polyols can be used to produce rigid foam. They are available in both aromatic and aliphatic versions. They are also available in mixed aliphatic-aromatic versions often made from recycled raw materials, typically polyethylene terephthalate (PET).
Acrylic polyols are generally used in higher performance applications where stability to ultraviolet light is required and also lower VOC coatings. Other uses include direct to metal coatings. As they are used where good UV resistance is required, such
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https://en.wikipedia.org/wiki/Discourse%20on%20Metaphysics
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The Discourse on Metaphysics (, 1686) is a short treatise by Gottfried Wilhelm Leibniz in which he develops a philosophy concerning physical substance, motion and resistance of bodies, and God's role within the universe. It is one of the few texts presenting in a consistent form the earlier philosophy of Leibniz.
The Discourse is closely connected to the epistolary discussion which he carried with Antoine Arnauld. However Leibniz refrained from sending the full text and it remained unpublished until the mid 19th century. Arnauld received only an abridged version in 37 points which resumed whole paragraphs and steered their discussion.
Summary
The metaphysical considerations proceed from God to the substantial world and back to the spiritual realm. The starting point for the work is the conception of God as an absolutely perfect being (I), that God is good but goodness exists independently of God (a rejection of divine command theory) (II), and that God has created the world in an ordered and perfect fashion (III–VII).
At the time of its writing Discourse made the controversial claim That the opinions of... scholastic philosophers are not to be wholly despised (XI). Early work in modern philosophy during the 17th century were based on a rejection of many of the precepts of medieval philosophy. Leibniz saw the failures of scholasticism merely as one of rigor. [If] some careful and meditative mind were to take the trouble to clarify and direct their thoughts in the manner of
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https://en.wikipedia.org/wiki/Nikolay%20Basov
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Nikolay Gennadiyevich Basov (; 14 December 1922 – 1 July 2001) was a Russian Soviet physicist and educator. For his fundamental work in the field of quantum electronics that led to the development of laser and maser, Basov shared the 1964 Nobel Prize in Physics with Alexander Prokhorov and Charles Hard Townes.
Early life
Basov was born in the town of Usman, now in Lipetsk Oblast in 1922. He finished school in 1941 in Voronezh, and was later called for military service at Kuibyshev Military Medical Academy. In 1943 he left the academy and served in the Red Army participating in the Second World War with the 1st Ukrainian Front.
Professional career
Basov graduated from Moscow Engineering Physics Institute (MEPhI) in 1950. He then held a professorship at MEPhI and also worked in the Lebedev Physical Institute (LPI), where he defended a dissertation for the Candidate of Sciences degree (equivalent to PhD) in 1953 and a dissertation for the Doctor of Sciences degree in 1956. Basov was the Director of the LPI in 1973–1988. He was elected as corresponding member of the USSR Academy of Sciences (Russian Academy of Sciences since 1991) in 1962 and Full Member of the Academy in 1966. In 1967, he was elected a Member of the Presidium of the Academy (1967—1990), and since 1990 he was the councillor of the Presidium of the USSR Academy of Sciences. In 1971 he was elected a Member of the German Academy of Sciences Leopoldina. He was Honorary President and Member of the International Ac
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https://en.wikipedia.org/wiki/Evolutionary%20neuroscience
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Evolutionary neuroscience is the scientific study of the evolution of nervous systems. Evolutionary neuroscientists investigate the evolution and natural history of nervous system structure, functions and emergent properties. The field draws on concepts and findings from both neuroscience and evolutionary biology. Historically, most empirical work has been in the area of comparative neuroanatomy, and modern studies often make use of phylogenetic comparative methods. Selective breeding and experimental evolution approaches are also being used more frequently.
Conceptually and theoretically, the field is related to fields as diverse as cognitive genomics, neurogenetics, developmental neuroscience, neuroethology, comparative psychology, evo-devo, behavioral neuroscience, cognitive neuroscience, behavioral ecology, biological anthropology and sociobiology.
Evolutionary neuroscientists examine changes in genes, anatomy, physiology, and behavior to study the evolution of changes in the brain. They study a multitude of processes including the evolution of vocal, visual, auditory, taste, and learning systems as well as language evolution and development. In addition, evolutionary neuroscientists study the evolution of specific areas or structures in the brain such as the amygdala, forebrain and cerebellum as well as the motor or visual cortex.
History
Studies of the brain began during ancient Egyptian times but studies in the field of evolutionary neuroscience began after the pub
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https://en.wikipedia.org/wiki/Marston%20Bates
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Marston Bates (July 23, 1906 – April 3, 1974) was an American zoologist and environmental author. Bates' studies on mosquitoes contributed to the understanding of the epidemiology of yellow fever in northern South America.
Born in Michigan, Bates received a BS in biology from the University of Florida in 1927. From 1928 to 1931, he worked as an entomologist for the United Fruit Company in Central America. He received a PhD in zoology in 1934 from Harvard University. He worked for the Rockefeller Foundation from 1935 to 1952, studying mosquito ecology, malaria, yellow fever, and human population. He lived for many years in Villavicencio between the mountains and the llanos in central Colombia. He served as special assistant to the president of the Rockefeller Foundation, 1950–1952. From 1952 until 1971 he was a professor at the University of Michigan. During that time, he also served as member of the National Research Council's expedition to the Ifalik Atoll in the South Pacific (1953), director of research at the University of Puerto Rico (1956-1957), and member of the Committee on Biological and Medical Sciences of the National Science Foundation (1952-1958). He was a Fellow of the Entomological Society of America in 1940 and an elected fellow of the American Academy of Arts and Sciences in 1958. He was the author of many popular science books. He was married to Nancy Bell Fairchild, daughter of the botanist David Fairchild and granddaughter of Alexander Graham Bell.
In 1
|
https://en.wikipedia.org/wiki/Contextualization
|
Contextualization may refer to:
Contextualization (Bible translation), the process of contextualising the biblical message as perceived in the missionary mandate originated by Jesus
Contextualization (computer science), an initialization phase setting or overriding properties having unknown or default values at the time of template creation
Contextualization (sociolinguistics), the use of language and discourse to signal relevant aspects of an interactional or communicative situation
Contextualism, a collection of views in philosophy which argue that actions or expressions can only be understood in context
See also
Context (disambiguation)
|
https://en.wikipedia.org/wiki/Reginald%20Punnett
|
Reginald Crundall Punnett FRS (; 20 June 1875 – 3 January 1967) was a British geneticist who co-founded, with William Bateson, the Journal of Genetics in 1910. Punnett is probably best remembered today as the creator of the Punnett square, a tool still used by biologists to predict the probability of possible genotypes of offspring. His Mendelism (1905) is sometimes said to have been the first textbook on genetics; it was probably the first popular science book to introduce genetics to the public.
Life and work
Reginald Punnett was born in 1875 in the town of Tonbridge in Kent, England. While recovering from a childhood bout of appendicitis, Punnett became acquainted with Jardine's Naturalist's Library and developed an interest in natural history. Punnett was educated at Clifton College.
Attending Gonville and Caius College, Cambridge, Punnett earned a bachelor's degree in zoology in 1898 and a master's degree in 1901. Between these degrees he worked as a demonstrator and part-time lecturer at the University of St. Andrews' Natural History Department. In October 1901, Punnett was back at Cambridge when he was elected to a Fellowship at Gonville and Caius College, working in zoology, primarily the study of worms, specifically nemerteans. It was during this time that he and William Bateson began a research collaboration, which lasted several years.
A
Punnett square
When Punnett was an undergraduate, Gregor Mendel's work on inheritance was largely unknown and unappre
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https://en.wikipedia.org/wiki/Molecular%20knot
|
In chemistry, a molecular knot is a mechanically interlocked molecular architecture that is analogous to a macroscopic knot. Naturally-forming molecular knots are found in organic molecules like DNA, RNA, and proteins. It is not certain that naturally occurring knots are evolutionarily advantageous to nucleic acids or proteins, though knotting is thought to play a role in the structure, stability, and function of knotted biological molecules. The mechanism by which knots naturally form in molecules, and the mechanism by which a molecule is stabilized or improved by knotting, is ambiguous. The study of molecular knots involves the formation and applications of both naturally occurring and chemically synthesized molecular knots. Applying chemical topology and knot theory to molecular knots allows biologists to better understand the structures and synthesis of knotted organic molecules.
The term knotane was coined by Vögtle et al. in 2000 to describe molecular knots by analogy with rotaxanes and catenanes, which are other mechanically interlocked molecular architectures. The term has not been broadly adopted by chemists and has not been adopted by IUPAC.
Naturally occurring molecular knots
Organic molecules containing knots may fall into the categories of slipknots or pseudo-knots. They are not considered mathematical knots because they are not a closed curve, but rather a knot that exists within an otherwise linear chain, with termini at each end. Knotted proteins are thoug
|
https://en.wikipedia.org/wiki/Supermolecule
|
The term supermolecule (or supramolecule) was introduced by Karl Lothar Wolf et al. (Übermoleküle) in 1937 to describe hydrogen-bonded acetic acid dimers. The study of non-covalent association of complexes of molecules has since developed into the field of supramolecular chemistry. The term supermolecule is sometimes used to describe supramolecular assemblies, which are complexes of two or more molecules (often macromolecules) that are not covalently bonded. The term supermolecule is also used in biochemistry to describe complexes of biomolecules, such as peptides and oligonucleotides composed of multiple strands.
See also
Macromolecule
Molecular self-assembly
Supramolecular assembly
Supramolecular chemistry
Van der Waals molecule
References
Supramolecular chemistry
|
https://en.wikipedia.org/wiki/Conservation%20genetics
|
Conservation genetics is an interdisciplinary subfield of population genetics that aims to understand the dynamics of genes in a population for the purpose of natural resource management and extinction prevention. Researchers involved in conservation genetics come from a variety of fields including population genetics, natural resources, molecular ecology, biology, evolutionary biology, and systematics. Genetic diversity is one of the three fundamental measures of biodiversity (along with species diversity and ecosystem diversity), so it is an important consideration in the wider field of conservation biology.
Genetic diversity
Genetic diversity is the total number of genetic characteristics in a species. It can be measured in several ways: observed heterozygosity, expected heterozygosity, the mean number of alleles per locus, or the percentage of polymorphic loci. Genetic diversity on the population level is a crucial focus for conservation genetics as it influences both the health and long-term survival of populations: decreased genetic diversity has been associated with reduced fitness, such as high juvenile mortality, diminished population growth, reduced immunity, and ultimately, higher extinction risk.
Heterozygosity, a fundamental measurement of genetic diversity in population genetics, plays an important role in determining the chance of a population surviving environmental change, novel pathogens not previously encountered, as well as the average fitness of a popul
|
https://en.wikipedia.org/wiki/Mike%20Lesk
|
Michael E. Lesk (born 1945) is an American computer scientist.
Biography
In the 1960s, Michael Lesk worked for the SMART Information Retrieval System project, wrote much of its retrieval code and did many of the retrieval experiments, as well as obtaining a BA degree in Physics and Chemistry from Harvard College in 1964 and a PhD from Harvard University in Chemical Physics in 1969.
From 1970 to 1984, Lesk worked at Bell Labs in the group that built Unix. Lesk wrote Unix tools for word processing (tbl, refer, and the standard ms macro package, all for troff), for compiling (Lex), and for networking (uucp). He also wrote the Portable I/O Library (the predecessor to stdio.h in C) and contributed significantly to the development of the C language preprocessor.
In 1984, he left to work for Bellcore, where he managed the computer science research group. There, Lesk worked on specific information systems applications, mostly with geography (a system for driving directions) and dictionaries (a system for disambiguating words in context).
In the 1990s, Lesk worked on a large chemical information system, the CORE project, with Cornell, Online Computer Library Center, American Chemical Society, and Chemical Abstracts Service.
From 1998 to 2002, Lesk headed the National Science Foundation's Division of Information and Intelligent Systems, where he oversaw Phase 2 of the NSF's Digital Library Initiative.
Currently, he is a professor on the faculty of the Library and Information Science
|
https://en.wikipedia.org/wiki/Cross-sectional%20study
|
In medical research, social science, and biology, a cross-sectional study (also known as a cross-sectional analysis, transverse study, prevalence study) is a type of observational study that analyzes data from a population, or a representative subset, at a specific point in time—that is, cross-sectional data.
In economics, cross-sectional studies typically involve the use of cross-sectional regression, in order to sort out the existence and magnitude of causal effects of one independent variable upon a dependent variable of interest at a given point in time. They differ from time series analysis, in which the behavior of one or more economic aggregates is traced through time.
In medical research, cross-sectional studies differ from case-control studies in that they aim to provide data on the entire population under study, whereas case-control studies typically include only individuals who have developed a specific condition and compare them with a matched sample, often a tiny minority, of the rest of the population. Cross-sectional studies are descriptive studies (neither longitudinal nor experimental). Unlike case-control studies, they can be used to describe, not only the odds ratio, but also absolute risks and relative risks from prevalences (sometimes called prevalence risk ratio, or PRR). They may be used to describe some feature of the population, such as prevalence of an illness, but cannot prove cause and effect. Longitudinal studies differ from both in making a se
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https://en.wikipedia.org/wiki/William%20B.%20Provine
|
William Ball Provine (February 19, 1942 – September 1, 2015) was an American historian of science and of evolutionary biology and population genetics. He was the Andrew H. and James S. Tisch Distinguished University Professor at Cornell University and was a professor in the Departments of History, Science and Technology Studies, and Ecology and Evolutionary Biology.
Biography
Provine was born in Tennessee. He held a B.S. in mathematics (1962), and an M.A. (1965) and Ph.D. (1970) in History of Science from the University of Chicago. He joined the Cornell faculty in 1969. He suffered seizures in 1995 due to a brain tumour. Provine died on September 1, 2015, due to complications from the tumor.
History of theoretical population genetics
Provine's Ph.D. thesis, later published as a book, documented the early origins of theoretical population genetics in the conflicts between the biostatistics and Mendelian schools of thought. He documented later developments in theoretical population genetics in his biography of Sewall Wright, who was still alive and available for interviews. In this book, Provine criticizes Wright for confounding three different concepts of adaptive landscape: genotype to fitness landscapes, allele frequency to fitness landscapes, and phenotype to fitness landscapes. Provine later grew critical of Wright's views on genetic drift, instead attributing observed effects to the consequences of inbreeding and consequent selection at linked sites. John H. Gillespie
|
https://en.wikipedia.org/wiki/PRN
|
PRN may refer to:
Computing
PRN:, a printer device name in DOS
Pseudorandom noise, in cryptography
Medicine
Pertactin (PRN), a virulent factor of the bacterium Bordetella pertussis
Pro re nata (P.R.N.), prescription jargon
PRN Forum, a precursor to the Journal of Pain and Symptom Management
Politics
National Reconstruction Party, Brazil
Nicaraguan Resistance Party, Nicaragua
, Mexico, an Institutional Revolutionary Party precursor
Radio
Performance Racing Network, an American NASCAR radio network
Premiere Radio Networks, another American network
Transport
Pacific RailNews, a defunct American hobbyist magazine
Paralympic route network, linking Paralympic games venues
Parton railway station, Cumbria, England
Pristina International Airport Adem Jashari, Kosovo (IATA:PRN)
Mac Crenshaw Memorial Airport, Greenville, Alabama, US (FAA LID:PRN)
Other uses
Packaging Recovery Note, per UK Producer Recovery Obligations
Praseodymium nitride, a chemical (formula: PrN)
Premier Retail Networks, a provider of in-store ad screens
See also
PR:NS (disambiguation)
Pern (disambiguation)
Porn (disambiguation)
|
https://en.wikipedia.org/wiki/Hipodil
|
Hipodil ( ) was a Bulgarian rock band, founded in the late 1980s in Sofia by four classmates from the local Mathematics High School.
Hipodil's popularity was based in large on their aggressive, sarcastic, sometimes vulgar and explicit but yet humorous lyrics. Because of that Hipodil were known as a "scandalous and rebellious" band. Their main goal was to entertain the listener and themselves; most of the lyrics concerned topics such as alcohol, sex, women, the status quo, etc.; they frequently ridiculed famous Bulgarian and non-Bulgarian people and even politicians (and sometimes songs). Nevertheless, the band had some pretty serious tracks with complex and socially oriented lyrics. All the lyrics were in Bulgarian and were written by vocalist Svetoslav Vitkov (Svetlyo). Most of the music was composed by guitarist Petar Todorov (Pesho). In a great number of songs, guest musicians took part, adding mainly to the brass section.
History
The four classmates from the Sofia's Mathematics High School Nikola Kavaldjiev, Miroslav Tellalov, Nikolay Savov and Petar Todorov formed in 1988 a punk band which played only their own songs in Bulgarian. The first public performance of the band was at Sofia's Summer Theatre, an open-air stage in the largest city park, where the band performed the song "Zidaromazachi" (Wallplasterers), a parody of the ruling communist regime, which got them into minor trouble with the authorities.
In 1992, after a couple of line-up changes and recruiting th
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https://en.wikipedia.org/wiki/Frank%20Di%20Giorgio
|
Frank Di Giorgio ( , ) is a Canadian former politician. He sat on Toronto City Council and represented Ward 12 York South—Weston from 2000 to 2018. Prior to the amalgamation of Toronto, Di Giorgio was a member of the North York City Council from 1985 to 1997, representing Ward 4.
Background
With a mathematics degree from McMaster University, he was a high school math teacher before entering politics.
Political career
North York Council
Di Giorgio was elected as Ward 4 Councillor to North York's council in the 1985 Toronto election defeating Barb Shiner. He was a close ally of Mayor Mel Lastman.
During his time as a North York Councillor, Di Giorgio served as a member of the Executive Committee and chaired all major standing committees, including Works, Transportation, Planning Advisory, Library Board, Parks and Recreation and Capital Planning. His contribution as founding director of the Ford Performing Arts Centre and his help in creating the Capital Planning Committee brought both a knowledgeable voice and prudent change to North York.
Toronto City Council
In his role as Toronto city councillor Di Giorgio was appointed budget chief under Mayor Rob Ford in 2013.
During the mayoralty of John Tory he also held important Council committee positions. He was a member of the Executive Committee and sat on the Board of Directors for Toronto Community Housing Corporation (TCHC) as the Mayor's designate.
Di Giorgio ran for re-election as councillor in the newly formed Ward 5
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https://en.wikipedia.org/wiki/ASMS
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ASMS may stand for:
American Society for Mass Spectrometry, a professional society, as well as the society's annual meeting
Arkansas School for Mathematics, Sciences, and the Arts
Association of Salaried Medical Specialists, a New Zealand trade union.
Australian Science and Mathematics School on the campus of Flinders University.
Annie Sullivan Middle School Franklin, Massachusetts
Advanced Surface Missile System – US naval combat system, predecessor of Aegis.
Alternative School for Math and Science in Corning, NY
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https://en.wikipedia.org/wiki/Ronald%20Coifman
|
Ronald Raphael Coifman is the Sterling professor of Mathematics at Yale University. Coifman earned a doctorate from the University of Geneva in 1965, supervised by Jovan Karamata.
Coifman is a member of the American Academy of Arts and Sciences, the Connecticut Academy of Science and Engineering, and the National Academy of Sciences. He is a recipient of the 1996 DARPA Sustained Excellence Award, the 1996 Connecticut Science Medal, the 1999 Pioneer Award of the International Society for Industrial and Applied Science, and the 1999 National Medal of Science.
In 2013, he co-founded ThetaRay, a cyber security and big data analytics company.
In 2018, he received the Rolf Schock Prize for Mathematics. In 2024 he will be awarded the George David Birkhoff Prize.
References
External links
Scientific Data Has Become So Complex, We Have to Invent New Math to Deal With It, Wired
Members of the United States National Academy of Sciences
Living people
20th-century American mathematicians
21st-century American mathematicians
Israeli Jews
Israeli mathematicians
Yale University faculty
National Medal of Science laureates
1941 births
Israeli emigrants to the United States
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https://en.wikipedia.org/wiki/FLP
|
FLP may refer to:
Computer science
FLP impossibility proof in computer science
Organizations
Family Limited Partnership, holding companies
Forever Living Products, a US MLM company
Politics
Farmer–Labor Party, a former US party
Fatherland Party (Norway), a former party (Norwegian: Fedrelandspartiet)
Fiji Labour Party
Finnish Rural Party, a former party (Swedish: Finlands landsbygdsparti)
Le front de libération populaire, a former party in Quebec, Canada
Popular Liberation Front (Spain), a former party (Spanish: Frente de Liberación Popular)
Science
Flurbiprofen
Frustrated Lewis pair
Transportation
Lugano–Ponte Tresa railway (Italian: Ferrovia Lugano–Ponte Tresa)
Marion County Regional Airport, in Arkansas, United States
Satish Dhawan Space Centre First Launch Pad, in India
See also
Windows Fundamentals for Legacy PCs (WinFLP)
|
https://en.wikipedia.org/wiki/Henry%20Farnam
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Henry Farnam (November 9, 1803 – October 4, 1883) was an American philanthropist and railroad president.
Biography
He was born in Scipio, New York, and grew up working on his father's farm. By his teenage years, he had begun studying mathematics on his own and in 1820 he gained employment initially as a camp cook on the Erie Canal. Under the wing of Benjamin Wright, America's most famous Civil Engineer at the time and a man who encouraged many young men to study Civil Engineering, Henry Farnam learned Surveying and was soon employed as a Surveyor on the Erie Canal. In 1825 he began working for the New Haven and Northampton Canal, becoming construction superintendent in 1827.
He moved to New Haven, Connecticut, in 1839 and was instrumental in building the railroad that replaced the canal there in 1848.
In 1850 he moved to Illinois where he partnered with Joseph E. Sheffield to build the Chicago, Rock Island and Pacific Railroad. In 1854 he became that railroad's president, an office he held until his retirement in 1863.
In 1868 he moved back to New Haven where he remained until his death in 1883. His son Henry Walcott Farnam was an economist, and served as president of the American Economic Association in 1911.
References
1803 births
1883 deaths
19th-century American railroad executives
Chicago, Rock Island and Pacific Railroad
People from Scipio, New York
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https://en.wikipedia.org/wiki/Secure%20voice
|
Secure voice (alternatively secure speech or ciphony) is a term in cryptography for the encryption of voice communication over a range of communication types such as radio, telephone or IP.
History
The implementation of voice encryption dates back to World War II when secure communication was paramount to the US armed forces. During that time, noise was simply added to a voice signal to prevent enemies from listening to the conversations. Noise was added by playing a record of noise in sync with the voice signal and when the voice signal reached the receiver, the noise signal was subtracted out, leaving the original voice signal. In order to subtract out the noise, the receiver need to have exactly the same noise signal and the noise records were only made in pairs; one for the transmitter and one for the receiver. Having only two copies of records made it impossible for the wrong receiver to decrypt the signal. To implement the system, the army contracted Bell Laboratories and they developed a system called SIGSALY. With SIGSALY, ten channels were used to sample the voice frequency spectrum from 250 Hz to 3 kHz and two channels were allocated to sample voice pitch and background hiss. In the time of SIGSALY, the transistor had not been developed and the digital sampling was done by circuits using the model 2051 Thyratron vacuum tube. Each SIGSALY terminal used 40 racks of equipment weighing 55 tons and filled a large room. This equipment included radio transmitters
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https://en.wikipedia.org/wiki/Delta%20bond
|
In chemistry, delta bonds (δ bonds) are covalent chemical bonds, where four lobes of one involved atomic orbital overlap four lobes of the other involved atomic orbital. This overlap leads to the formation of a bonding molecular orbital with two nodal planes which contain the internuclear axis and go through both atoms.
The Greek letter δ in their name refers to d orbitals, since the orbital symmetry of the δ bond is the same as that of the usual (4-lobed) type of d orbital when seen down the bond axis. This type of bonding is observed in atoms that have occupied d orbitals with low enough energy to participate in covalent bonding, for example, in organometallic species of transition metals. Some rhenium, molybdenum, technetium, and chromium compounds contain a quadruple bond, consisting of one σ bond, two π bonds and one δ bond.
The orbital symmetry of the δ bonding orbital is different from that of a π antibonding orbital, which has one nodal plane containing the internuclear axis and a second nodal plane perpendicular to this axis between the atoms.
The δ notation was introduced by Robert Mulliken in 1931. The first compound identified as having a δ bond was potassium octachlorodirhenate(III). In 1965, F. A. Cotton reported that there was δ-bonding as part of the rhenium–rhenium quadruple bond in the [Re2Cl8]2− ion. Another interesting example of a δ bond is proposed in cyclobutadieneiron tricarbonyl between an iron d orbital and the four p orbitals of the attached cycl
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https://en.wikipedia.org/wiki/David%20Crighton
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David George Crighton, FRS (15 November 1942 – 12 April 2000) was a British mathematician and physicist.
Life
Crighton was born in Llandudno, North Wales, where his mother, Violet Grace Garrison, had been sent because of the bombing of London during the Second World War. He did not become interested in mathematics until his last two years at Watford Grammar School for Boys. He entered St John's College, Cambridge, in 1961 and started lecturing at Woolwich Polytechnic (today University of Greenwich) in 1964, having completed only his bachelor's degree.
A few years later he met John Ffowcs Williams and started to work for him at Imperial College London, while simultaneously studying for his doctorate (awarded in 1969) at the same place. In 1974, he was appointed as a research fellow in the Department of Engineering at the University of Cambridge. However, he never took up this post, but instead accepted the chair in applied mathematics at the University of Leeds, which he held until 1986.
He then returned to Cambridge as Professor of Applied Mathematics in succession to George Batchelor.
Later, he became a well-loved Master of Jesus College (1997–2000), and was head of the Applied Mathematics and Theoretical Physics Department (DAMTP) in Cambridge between 1991 and 2000, where he was held in huge regard by the faculty and students.
Away from his mathematical work, Crighton was a devotee of the music of Richard Wagner, as well as music for the piano.
Work
Crighton's scient
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https://en.wikipedia.org/wiki/Devarda%27s%20alloy
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Devarda's alloy (CAS # 8049-11-4) is an alloy of aluminium (44% – 46%), copper (49% – 51%) and zinc (4% – 6%).
Devarda's alloy is used as reducing agent in analytical chemistry for the determination of nitrates after their reduction to ammonia under alkaline conditions. It is named for Italian chemist Arturo Devarda (1859–1944), who synthesised it at the end of the 19th century to develop a new method to analyze nitrate in Chile saltpeter.
It was often used in the quantitative or qualitative analysis of nitrates in agriculture and soil science before the development of ion chromatography, the predominant analysis method largely adopted worldwide today.
General mechanism
When a solution of nitrate ions is mixed with aqueous sodium hydroxide, adding Devarda's alloy and heating the mixture gently, liberates ammonia gas. After conversion under the form of ammonia, the total nitrogen is then determined by Kjeldahl method.
The reduction of nitrate by the Devarda's alloy is given by the following equation:
3 + 8 Al + 5 + 18 → 3 + 8
Distinction between NO3− and NO2− with spot tests
To distinguish between nitrate and nitrite, dilute HCl must be added to the nitrate. The brown ring test can also be used.
Similarity with the Marsh test
Devarda's alloy is a reducing agent that was commonly used in wet analytical chemistry to produce so-called nascent hydrogen under alkaline conditions in situ. In the Marsh test, used for arsenic determination, hydrogen is generated by contact
|
https://en.wikipedia.org/wiki/Richard%20A.%20Muller
|
Richard A. Muller (born January 6, 1944) is an American physicist and emeritus professor of physics at the University of California, Berkeley. He was also a faculty senior scientist at the Lawrence Berkeley National Laboratory. In early 2010, Muller and his daughter Elizabeth Muller founded the group Berkeley Earth, an independent 501(c)(3) non-profit aimed at addressing some of the major concerns of the climate change skeptics, in particular the global surface temperature record. In 2016, Richard and Elizabeth Muller co-founded Deep Isolation, a private company seeking to dispose of nuclear waste in deep boreholes.
Early life, education and career
Muller, who grew up in the South Bronx, attended public schools in New York City, including PS 65 (on 141st St), Junior High School 22 (on 167th St), and the Bronx High School of Science. Muller obtained an A.B. degree at Columbia University (New York) and a Ph.D. degree in physics from University of California, Berkeley. Muller began his career as a graduate student under Nobel laureate Luis Alvarez performing particle physics experiments and working with bubble chambers. During his early years he also helped to co-create accelerator mass spectrometry and made some of the first measurements of anisotropy in the cosmic microwave background.
Subsequently, Muller branched out into other areas of science, and in particular the Earth sciences. His work has included attempting to understand the ice ages, dynamics at the core-mantle
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https://en.wikipedia.org/wiki/Nicolas%20Courtois
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Nicolas Tadeusz Courtois (born 14 November 1971) is a cryptographer and senior lecturer in computer science at University College London.
Courtois was one of the co-authors of both the XSL attack against block ciphers, such as the Advanced Encryption Standard, and the XL system for solving systems of algebraic equations used in the attack. Other cryptographic results of Courtois include algebraic attacks on stream ciphers, attacks on the KeeLoq and Hitag 2 systems used for remote keyless automobile entry systems, and an analysis of cryptographic weaknesses in public transit smart cards including the London Underground Oyster card and the Dutch OV-chipkaart. More recently, he has written about cryptocurrency.
Courtois graduated from University of Paris VI: Pierre et Marie Curie, where he received his doctoral degree in cryptography.
References
Modern cryptographers
French cryptographers
1971 births
Living people
Pierre and Marie Curie University alumni
|
https://en.wikipedia.org/wiki/Principles%20and%20Standards%20for%20School%20Mathematics
|
Principles and Standards for School Mathematics (PSSM) are guidelines produced by the National Council of Teachers of Mathematics (NCTM) in 2000, setting forth recommendations for mathematics educators. They form a national vision for preschool through twelfth grade mathematics education in the US and Canada. It is the primary model for standards-based mathematics.
The NCTM employed a consensus process that involved classroom teachers, mathematicians, and educational researchers. The resulting document sets forth a set of six principles (Equity, Curriculum, Teaching, Learning, Assessment, and Technology) that describe NCTM's recommended framework for mathematics programs, and ten general strands or standards that cut across the school mathematics curriculum. These strands are divided into mathematics content (Number and Operations, Algebra, Geometry, Measurement, and Data Analysis and Probability) and processes (Problem Solving, Reasoning and Proof, Communication, Connections, and Representation). Specific expectations for student learning are described for ranges of grades (preschool to 2, 3 to 5, 6 to 8, and 9 to 12).
Origins
The Principles and Standards for School Mathematics was developed by the NCTM. The NCTM's stated intent was to improve mathematics education. The contents were based on surveys of existing curriculum materials, curricula and policies from many countries, educational research publications, and government agencies such as the U.S. National Science
|
https://en.wikipedia.org/wiki/National%20Council%20of%20Teachers%20of%20Mathematics
|
Founded in 1920, The National Council of Teachers of Mathematics (NCTM) is a professional organization for schoolteachers of mathematics in the United States. One of its goals is to improve the standards of mathematics in education. NCTM holds annual national and regional conferences for teachers and publishes five journals.
Journals
NCTM publishes five official journals. All are available in print and online versions.
Teaching Children Mathematics supports improvement of pre-K–6 mathematics education by serving as a resource for teachers so as to provide more and better mathematics for all students. It is a forum for the exchange of mathematics idea, activities, and pedagogical strategies, and or sharing and interpreting research.
Mathematics Teaching in the Middle School supports the improvement of grade 5–9 mathematics education by serving as a resource for practicing and prospective teachers, as well as supervisors and teacher educators. It is a forum for the exchange of mathematics idea, activities, and pedagogical strategies, and or sharing and interpreting research.
Mathematics Teacher is devoted to improving mathematics instruction for grades 8–14 and supporting teacher education programs. It provides a forum for sharing activities and pedagogical strategies, deepening understanding of mathematical ideas, and linking mathematical education research to practice.
Mathematics Teacher Educator, published jointly with the Association of Mathematics Teacher Educators,
|
https://en.wikipedia.org/wiki/Polyinstantiation
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Polyinstantiation in computer science is the concept of type (class, database row or otherwise) being instantiated into multiple independent instances (objects, copies). It may also indicate, such as in the case of database polyinstantiation, that two different instances have the same name (identifier, primary key).
Operating system security
In Operating system security, polyinstantiation is the concept of creating a user or process specific view of a shared resource. I.e. Process A cannot affect process B by writing malicious code to a shared resource, such as UNIX directory /tmp.
Polyinstantiation of shared resources have similar goals as process isolation, an application of virtual memory, where processes are assigned their own isolated virtual address space to prevent process A writing into the memory space of process B.
Database
In databases, polyinstantiation is database-related SQL (structured query language) terminology. It allows a relation to contain multiple rows with the same primary key; the multiple instances are distinguished by their security levels. It occurs because of mandatory policy. Depending on the security level established, one record contains sensitive information, and the other one does not, that is, a user will see the record's information depending on his/her level of confidentiality previously dictated by the company's policy
Consider the following table, where the primary key is Name and λ(x) is the security level:
Although useful from a
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https://en.wikipedia.org/wiki/Proband
|
In medical genetics and other medical fields, a proband, proposito (male proband), or proposita (female proband) is a particular subject (human or other animal) being studied or reported on. On pedigrees, the proband is noted with a square (male) or circle (female) shaded accordingly. Denoting the proband is important, so the relationship to other individuals can be seen and patterns established.
In most cases, the proband is the first affected family member who seeks medical attention for a genetic disorder. Among the ancestors of the proband, other subjects may manifest the disease, but the proband typically refers to the member seeking medical attention or being studied, even if affected ancestors are known. Often, affected ancestors are unknown due to the lack of information regarding those individuals or about the disease at the time they lived. Other ancestors might be undiagnosed due to the incomplete penetrance or variable expressivity.
The diagnosis of a proband raises the index of suspicion for the proband's relatives and some of them may be diagnosed with the same disease. Conventionally, when drawing a pedigree chart, instead of the first diagnosed person, the proband may be chosen from among the affected ancestors (parents, grandparents) from the first generation where the disease is found.
The term "proband" is also used in genealogy, where it denotes the root node of an ahnentafel, also referred to as the progenitor.
References
Classical genetics
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