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https://en.wikipedia.org/wiki/Defuzzification
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Defuzzification is the process of producing a quantifiable result in crisp logic, given fuzzy sets and corresponding membership degrees. It is the process that maps a fuzzy set to a crisp set. It is typically needed in fuzzy control systems. These systems will have a number of rules that transform a number of variables into a fuzzy result, that is, the result is described in terms of membership in fuzzy sets. For example, rules designed to decide how much pressure to apply might result in "Decrease Pressure (15%), Maintain Pressure (34%), Increase Pressure (72%)". Defuzzification is interpreting the membership degrees of the fuzzy sets into a specific decision or real value.
The simplest but least useful defuzzification method is to choose the set with the highest membership, in this case, "Increase Pressure" since it has a 72% membership, and ignore the others, and convert this 72% to some number. The problem with this approach is that it loses information. The rules that called for decreasing or maintaining pressure might as well have not been there in this case.
A common and useful defuzzification technique is center of gravity. First, the results of the rules must be added together in some way. The most typical fuzzy set membership function has the graph of a triangle. Now, if this triangle were to be cut in a straight horizontal line somewhere between the top and the bottom, and the top portion were to be removed, the remaining portion forms a trapezoid. The first step
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https://en.wikipedia.org/wiki/Mount%20Stromlo%20Observatory
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Mount Stromlo Observatory located just outside Canberra, Australia, is part of the Research School of Astronomy and Astrophysics at the Australian National University (ANU).
History
The observatory was established in 1924 as The Commonwealth Solar Observatory. The Mount Stromlo site had already been used for observations in the previous decade, a small observatory being established there by Pietro Baracchi using the Oddie telescope located there in 1911. The dome built to house the Oddie telescope was the first Commonwealth building constructed in the newly established Australian Capital Territory. In 1911 a delegation for an Australian Solar Observatory went to London seeking Commonwealth assistance. The League of the Empire sought subscriptions to assist raising funds. Survey work to determine the site's suitability had begun as soon as the idea of a new Capital was established. By 1909 the Australian Association for the Advancement of Science was assisted in this effort by Hugh Mahon (Minister for Home Affairs). Until World War II, the observatory specialised in solar and atmospheric observations. During the war the workshops contributed to the war effort by producing gun sights, and other optical equipment. After the war, the observatory shifted direction to stellar and galactic astronomy and was renamed The Commonwealth Observatory. Dr R. Wooley Director of the Observatory, worked to gain support for a larger reflector, arguing that the southern hemisphere should attem
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https://en.wikipedia.org/wiki/Variation%20of%20parameters
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In mathematics, variation of parameters, also known as variation of constants, is a general method to solve inhomogeneous linear ordinary differential equations.
For first-order inhomogeneous linear differential equations it is usually possible to find solutions via integrating factors or undetermined coefficients with considerably less effort, although those methods leverage heuristics that involve guessing and do not work for all inhomogeneous linear differential equations.
Variation of parameters extends to linear partial differential equations as well, specifically to inhomogeneous problems for linear evolution equations like the heat equation, wave equation, and vibrating plate equation. In this setting, the method is more often known as Duhamel's principle, named after Jean-Marie Duhamel (1797–1872) who first applied the method to solve the inhomogeneous heat equation. Sometimes variation of parameters itself is called Duhamel's principle and vice versa.
History
The method of variation of parameters was first sketched by the Swiss mathematician Leonhard Euler (1707–1783), and later completed by the Italian-French mathematician Joseph-Louis Lagrange (1736–1813).
A forerunner of the method of variation of a celestial body's orbital elements appeared in Euler's work in 1748, while he was studying the mutual perturbations of Jupiter and Saturn. In his 1749 study of the motions of the earth, Euler obtained differential equations for the orbital elements. In 1753, he
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https://en.wikipedia.org/wiki/Kappa%20curve
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In geometry, the kappa curve or Gutschoven's curve is a two-dimensional algebraic curve resembling the Greek letter . The kappa curve was first studied by Gérard van Gutschoven around 1662. In the history of mathematics, it is remembered as one of the first examples of Isaac Barrow's application of rudimentary calculus methods to determine the tangent of a curve. Isaac Newton and Johann Bernoulli continued the studies of this curve subsequently.
Using the Cartesian coordinate system it can be expressed as
or, using parametric equations,
In polar coordinates its equation is even simpler:
It has two vertical asymptotes at , shown as dashed blue lines in the figure at right.
The kappa curve's curvature:
Tangential angle:
Tangents via infinitesimals
The tangent lines of the kappa curve can also be determined geometrically using differentials and the elementary rules of infinitesimal arithmetic. Suppose and are variables, while a is taken to be a constant. From the definition of the kappa curve,
Now, an infinitesimal change in our location must also change the value of the left hand side, so
Distributing the differential and applying appropriate rules,
Derivative
If we use the modern concept of a functional relationship and apply implicit differentiation, the slope of a tangent line to the kappa curve at a point is:
References
External links
A Java applet for playing with the curve
Algebraic curves
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https://en.wikipedia.org/wiki/124%20%28number%29
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124 (one hundred [and] twenty-four) is the natural number following 123 and preceding 125.
In mathematics
124 is an untouchable number, meaning that it is not the sum of proper divisors of any positive number.
It is a stella octangula number, the number of spheres packed in the shape of a stellated octahedron. It is also an icosahedral number.
There are 124 different polygons of length 12 formed by edges of the integer lattice, counting two polygons as the same only when one is a translated copy of the other.
124 is a perfectly partitioned number, meaning that it divides the number of partitions of 124. It is the first number to do so after 1, 2, and 3.
See also
The year AD 124 or 124 BC
124th (disambiguation)
List of highways numbered 124
References
Integers
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https://en.wikipedia.org/wiki/Disjoint-set%20data%20structure
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In computer science, a disjoint-set data structure, also called a union–find data structure or merge–find set, is a data structure that stores a collection of disjoint (non-overlapping) sets. Equivalently, it stores a partition of a set into disjoint subsets. It provides operations for adding new sets, merging sets (replacing them by their union), and finding a representative member of a set. The last operation makes it possible to find out efficiently if any two elements are in the same or different sets.
While there are several ways of implementing disjoint-set data structures, in practice they are often identified with a particular implementation called a disjoint-set forest. This is a specialized type of forest which performs unions and finds in near-constant amortized time. To perform a sequence of addition, union, or find operations on a disjoint-set forest with nodes requires total time , where is the extremely slow-growing inverse Ackermann function. Disjoint-set forests do not guarantee this performance on a per-operation basis. Individual union and find operations can take longer than a constant times time, but each operation causes the disjoint-set forest to adjust itself so that successive operations are faster. Disjoint-set forests are both asymptotically optimal and practically efficient.
Disjoint-set data structures play a key role in Kruskal's algorithm for finding the minimum spanning tree of a graph. The importance of minimum spanning trees mea
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https://en.wikipedia.org/wiki/Certified%20health%20physicist
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Certified Health Physicist is an official title granted by the American Board of Health Physics, the certification board for health physicists in the United States. A Certified Health Physicist is designated by the letters CHP or DABHP (Diplomate of the American Board of Health Physics) after his or her name.
A certification by the ABHP is not a license to practice and does not confer any legal qualification to practice health physics. However, the certification is well respected and indicates a high level of achievement by those who obtain it.
Certified Health Physicists are plenary or emeritus members of the American Academy of Health Physics (AAHP). In 2019, the AAHP web site listed over 1600 plenary and emeritus members.
Professional responsibilities
A person certified as a health physicist has a responsibility to uphold the professional integrity associated with the certification to promote the practice and science of radiation safety. It is expected that such a person will always give health physics information based on the highest standards of science and professional ethics. A certified individual has a responsibility to remain professionally active in the health physics field and remain technically competent in the scientific, technical and regulatory developments in the field.
General requirements required to receive the certification
The requirements for prospective candidates for certification are
Academics. At least a bachelor's degree from an accredited co
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https://en.wikipedia.org/wiki/Beta%20function%20%28physics%29
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In theoretical physics, specifically quantum field theory, a beta function, β(g), encodes the dependence of a coupling parameter, g, on the energy scale, μ, of a given physical process described by quantum field theory.
It is defined as
and, because of the underlying renormalization group, it has no explicit dependence on μ, so it only depends on μ implicitly through g.
This dependence on the energy scale thus specified is known as the running of the coupling parameter, a fundamental
feature of scale-dependence in quantum field theory, and its explicit computation is achievable through a variety of mathematical techniques.
Scale invariance
If the beta functions of a quantum field theory vanish, usually at particular values of the coupling parameters, then the theory is said to be scale-invariant. Almost all scale-invariant QFTs are also conformally invariant. The study of such theories is conformal field theory.
The coupling parameters of a quantum field theory can run even if the corresponding classical field theory is scale-invariant. In this case, the non-zero beta function tells us that the classical scale invariance is anomalous.
Examples
Beta functions are usually computed in some kind of approximation scheme. An example is perturbation theory, where one assumes that the coupling parameters are small. One can then make an expansion in powers of the coupling parameters and truncate the higher-order terms (also known as higher loop contributions, due to the num
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https://en.wikipedia.org/wiki/Eclogite
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Eclogite () is a metamorphic rock containing garnet (almandine-pyrope) hosted in a matrix of sodium-rich pyroxene (omphacite). Accessory minerals include kyanite, rutile, quartz, lawsonite, coesite, amphibole, phengite, paragonite, zoisite, dolomite, corundum and, rarely, diamond. The chemistry of primary and accessory minerals is used to classify three types of eclogite (A, B, and C). The broad range of eclogitic compositions has led a longstanding debate on the origin of eclogite xenoliths as subducted, altered oceanic crust.
Origins
Eclogites typically result from high to ultrahigh pressure metamorphism of mafic rock at low thermal gradients of < as it is subducted to the lower crust to upper mantle depths in a subduction zone.
Classification
Eclogites are defined as bi-mineralic, broadly basaltic rocks which have been classified into Groups A, B and C based on the chemistry of their primary mineral phases, garnet and clinopyroxene. The classification distinguishes each group based on the jadeite content of clinopyroxene and pyrope in garnet. The rocks are gradationally less mafic (as defined by SiO2 and MgO) from group A to C, where the least mafic Group C contains higher alkali contents.
The transitional nature between groups A, B and C correlates with their mode of emplacement at the surface. Group A derive from cratonic regions of Earth's crust, brought to the surface as xenoliths from depths greater than 150 km during kimberlite eruptions. Group B show strong
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https://en.wikipedia.org/wiki/Free%20electron%20model
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In solid-state physics, the free electron model is a quantum mechanical model for the behaviour of charge carriers in a metallic solid. It was developed in 1927, principally by Arnold Sommerfeld, who combined the classical Drude model with quantum mechanical Fermi–Dirac statistics and hence it is also known as the Drude–Sommerfeld model.
Given its simplicity, it is surprisingly successful in explaining many experimental phenomena, especially
the Wiedemann–Franz law which relates electrical conductivity and thermal conductivity;
the temperature dependence of the electron heat capacity;
the shape of the electronic density of states;
the range of binding energy values;
electrical conductivities;
the Seebeck coefficient of the thermoelectric effect;
thermal electron emission and field electron emission from bulk metals.
The free electron model solved many of the inconsistencies related to the Drude model and gave insight into several other properties of metals. The free electron model considers that metals are composed of a quantum electron gas where ions play almost no role. The model can be very predictive when applied to alkali and noble metals.
Ideas and assumptions
In the free electron model four main assumptions are taken into account:
Free electron approximation: The interaction between the ions and the valence electrons is mostly neglected, except in boundary conditions. The ions only keep the charge neutrality in the metal. Unlike in the Drude model, the ions
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https://en.wikipedia.org/wiki/Iterated%20logarithm
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In computer science, the iterated logarithm of , written (usually read "log star"), is the number of times the logarithm function must be iteratively applied before the result is less than or equal to . The simplest formal definition is the result of this recurrence relation:
On the positive real numbers, the continuous super-logarithm (inverse tetration) is essentially equivalent:
i.e. the base b iterated logarithm is if n lies within the interval , where denotes tetration. However, on the negative real numbers, log-star is , whereas for positive , so the two functions differ for negative arguments.
The iterated logarithm accepts any positive real number and yields an integer. Graphically, it can be understood as the number of "zig-zags" needed in Figure 1 to reach the interval on the x-axis.
In computer science, is often used to indicate the binary iterated logarithm, which iterates the binary logarithm (with base ) instead of the natural logarithm (with base e).
Mathematically, the iterated logarithm is well-defined for any base greater than , not only for base and base e.
Analysis of algorithms
The iterated logarithm is useful in analysis of algorithms and computational complexity, appearing in the time and space complexity bounds of some algorithms such as:
Finding the Delaunay triangulation of a set of points knowing the Euclidean minimum spanning tree: randomized O(n n) time.
Fürer's algorithm for integer multiplication: O(n log n 2O( n)).
Finding an
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https://en.wikipedia.org/wiki/Cauchy%E2%80%93Euler%20equation
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In mathematics, an Euler–Cauchy equation, or Cauchy–Euler equation, or simply Euler's equation is a linear homogeneous ordinary differential equation with variable coefficients. It is sometimes referred to as an equidimensional equation. Because of its particularly simple equidimensional structure, the differential equation can be solved explicitly.
The equation
Let be the nth derivative of the unknown function . Then a Cauchy–Euler equation of order n has the form
The substitution (that is, ; for , one might replace all instances of by , which extends the solution's domain to ) may be used to reduce this equation to a linear differential equation with constant coefficients. Alternatively, the trial solution may be used to directly solve for the basic solutions.
Second order – solving through trial solution
The most common Cauchy–Euler equation is the second-order equation, appearing in a number of physics and engineering applications, such as when solving Laplace's equation in polar coordinates. The second order Cauchy–Euler equation is
We assume a trial solution
Differentiating gives and
Substituting into the original equation leads to requiring
Rearranging and factoring gives the indicial equation
We then solve for m. There are three particular cases of interest:
Case 1 of two distinct roots, and ;
Case 2 of one real repeated root, ;
Case 3 of complex roots, .
In case 1, the solution is
In case 2, the solution is
To get to this solution, the metho
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https://en.wikipedia.org/wiki/Paul%20Adams
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Paul Adams may refer to:
Academics
Paul L. Adams (academic) (1915–1984), president of Roberts Wesleyan College and candidate for Governor of New York
Paul Adams (scientist), British professor of neurobiology at Stony Brook University
Paul C. Adams, professor of geography at University of Texas at Austin
Politics
Paul Adams (Massachusetts politician), Massachusetts politician
Paul Adams (New Zealand politician) (born 1947/48), rally driver and former politician from New Zealand
Sports
Paul Adams (American football coach) (1936–2019), American football player and Hall of Fame high school coach
Paul Adams (center) (1919–1995), American football player and coach
Paul Adams (cricketer) (born 1977), South African cricketer
Paul Adams (coach) (1921–1986), American football, cross country running, and track and field coach
Paul Adams (sport shooter) (born 1992), Australian sport shooter
Paul Adams (umpire) (born 1949), English cricket umpire
Other
Paul Adams (journalist) (born 1961), English BBC television news correspondent
Paul Adams (musician) (born 1951), musician, writer, and musical instrument builder
Paul Adams (property developer) (born 1948/1949), New Zealand businessman and philanthropist
Paul D. Adams (1906–1987), U.S. Army general
Paul L. Adams (Michigan judge) (1908–1990), member of the Michigan Supreme Court
Paul Adams (pilot) (1922–2013), World War II pilot with the Tuskegee Airmen
See also
Adams (surname)
Paul Adam (disambiguation)
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https://en.wikipedia.org/wiki/Richard%20Axel
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Richard Axel (born July 2, 1946) is an American molecular biologist and university professor in the Department of Neuroscience at Columbia University and investigator at the Howard Hughes Medical Institute. His work on the olfactory system won him and Linda Buck, a former postdoctoral research scientist in his group, the Nobel Prize in Physiology or Medicine in 2004.
Education and early life
Born in New York City to Polish Jewish immigrants, Axel grew up in Brooklyn. He graduated from Stuyvesant High School in 1963, (along with Bruce Bueno de Mesquita and Alexander Rosenberg), received his B.A. in 1967 from Columbia University, and his M.D. in 1971 from Johns Hopkins University. However, he was poorly suited to medicine and graduated on the promise to his department chairman that he would not practice clinically. He found his calling in research and returned to Columbia later that year, eventually becoming a full professor in 1978.
Research and career
During the late 1970s, Axel, along with microbiologist Saul J. Silverstein and geneticist Michael H. Wigler, discovered a technique of cotransformation via transfection, a process which allows foreign DNA to be inserted into a host cell to produce certain proteins.
A family of patents, now colloquially referred to as the "Axel patents", covering this technique were filed for February 1980 and were issued in August 1983. As a fundamental process in recombinant DNA research as performed at pharmaceutical and biotech companies,
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https://en.wikipedia.org/wiki/129%20%28number%29
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129 (one hundred [and] twenty-nine) is the natural number following 128 and preceding 130.
In mathematics
129 is the sum of the first ten prime numbers. It is the smallest number that can be expressed as a sum of three squares in four different ways: , , , and .
129 is the product of only two primes, 3 and 43, making 129 a semiprime. Since 3 and 43 are both Gaussian primes, this means that 129 is a Blum integer.
129 is a repdigit in base 6 (333).
129 is a happy number.
129 is a centered octahedral number.
In the military
Raytheon AGM-129 ACM (Advanced Cruise Missile) was a low observable, sub-sonic, jet-powered, air-launched cruise missile used by the United States Air Force
Soviet submarine K-129 (1960) was a Soviet Pacific Fleet nuclear submarine that sank in 1968
was a United States Navy Mission Buenaventura-class fleet oilers during World War II
was a Crosley-class high speed transport of the United States Navy
was the lead ship of her class of destroyer escort in the United States Navy
was a United States Navy Haskell-class attack transport during World War II
was a United States Navy Crater-class cargo ship during World War II
was a United States Navy Auk-class minesweeper for removing naval mines laid in the water
Agusta A129 Mangusta is an attack helicopter originally designed and produced by Italian company Agusta
The 129th Rescue Wing (129 RQW) is a unit of the California Air National Guard
In transportation
LZ 129 Hindenburg was a German ze
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https://en.wikipedia.org/wiki/Sigma%20bond
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In chemistry, sigma bonds (σ bonds) are the strongest type of covalent chemical bond. They are formed by head-on overlapping between atomic orbitals. Sigma bonding is most simply defined for diatomic molecules using the language and tools of symmetry groups. In this formal approach, a σ-bond is symmetrical with respect to rotation about the bond axis. By this definition, common forms of sigma bonds are s+s, pz+pz, s+pz and dz2+dz2 (where z is defined as the axis of the bond or the internuclear axis).
Quantum theory also indicates that molecular orbitals (MO) of identical symmetry actually mix or hybridize. As a practical consequence of this mixing of diatomic molecules, the wavefunctions s+s and pz+pz molecular orbitals become blended. The extent of this mixing (or hybridization or blending) depends on the relative energies of the MOs of like symmetry.
For homodiatomics (homonuclear diatomic molecules), bonding σ orbitals have no nodal planes at which the wavefunction is zero, either between the bonded atoms or passing through the bonded atoms. The corresponding antibonding, or σ* orbital, is defined by the presence of one nodal plane between the two bonded atoms.
Sigma bonds are the strongest type of covalent bonds due to the direct overlap of orbitals, and the electrons in these bonds are sometimes referred to as sigma electrons.
The symbol σ is the Greek letter sigma. When viewed down the bond axis, a σ MO has a circular symmetry, hence resembling a similarly sounding "
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https://en.wikipedia.org/wiki/K%C3%A1rm%C3%A1n%20vortex%20street
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In fluid dynamics, a Kármán vortex street (or a von Kármán vortex street) is a repeating pattern of swirling vortices, caused by a process known as vortex shedding, which is responsible for the unsteady separation of flow of a fluid around blunt bodies.
It is named after the engineer and fluid dynamicist Theodore von Kármán, and is responsible for such phenomena as the "singing" of suspended telephone or power lines and the vibration of a car antenna at certain speeds. Mathematical modeling of von Kármán vortex street can be performed using different techniques including but not limited to solving the full Navier-Stokes equations with k-epsilon, SST, k-omega and Reynolds stress, and large eddy simulation (LES) turbulence models, by numerically solving some dynamic equations such as the Ginzburg–Landau equation, or by use of a bicomplex variable.
Analysis
A vortex street forms only at a certain range of flow velocities, specified by a range of Reynolds numbers (Re), typically above a limiting Re value of about 90. The (global) Reynolds number for a flow is a measure of the ratio of inertial to viscous forces in the flow of a fluid around a body or in a channel, and may be defined as a nondimensional parameter of the global speed of the whole fluid flow:
where:
= the free stream flow speed (i.e. the flow speed far from the fluid boundaries like the body speed relative to the fluid at rest, or an inviscid flow speed, computed through the Bernoulli equation), which is the
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https://en.wikipedia.org/wiki/Robert%20Haynes
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Robert Hall Haynes, OC, FRSC (August 27, 1931 – December 22, 1998) was a Canadian geneticist and biophysicist. He was the Distinguished Research Professor in the Department of Biology at York University. Haynes was best known for his contributions to the study of DNA repair and mutagenesis, and for helping promote the concept of terraforming through his invention of the term, ecopoiesis.
Haynes was one of the earliest geneticists to recognize the fundamental biologic importance of the vulnerability of DNA to damage and therefore the central role of DNA repair processes. As he noted, “DNA is composed of rather ordinary molecular subunits, which certainly are not endowed with any peculiar kind of quantum mechanical stability. Its very chemical vulgarity makes it prey to all the chemical horrors and misfortune that might befall any such molecule in a warm aqueous medium.”
Haynes early life and scientific contributions have been summarized by Kunz et al. (1993) and Kunz and Hanawalt (1999).
Incomplete timeline
1953, Haynes receives a degree in Mathematics and Physics, at the University of Western Ontario.
1957, Ph.D. in Biophysics, UWO
1984, Haynes creates the word ecopoiesis, a term that came to be widely used by writers and some proponents of terraforming and space exploration.
1987, The Genetics Society of Canada creates the Robert H. Haynes Young Scientist Award.
1988, Haynes serves as President of the 16th International Congress of Genetics.
1990, He is made an
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https://en.wikipedia.org/wiki/Walther%20M%C3%BCller
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Walther Müller (6 September 1905, in Hanover – 4 December 1979, in Walnut Creek, California) was a German physicist, most well known for his improvement of Hans Geiger's counter for ionizing radiation, now known as the Geiger-Müller tube.
Walther Müller studied physics, chemistry and philosophy at the University of Kiel. In 1925 he became the first PhD student of Hans Geiger, who had just got a professorship in Kiel. Their work on ionization of gases by collision lead to the invention of the Geiger-Müller counter, a now indispensable tool for measuring radioactive radiation.
After some time as professor at the University of Tübingen he worked for the rest of his professional life as industrial physicist (i. e. a physicist working in industrial R&D) in Germany, then as an advisor for the Australian Postmaster-General's Department Research Laboratories in Melbourne, and then as an industrial physicist in the United States, where he also founded a company to manufacture Geiger–Müller tubes.
References
1905 births
1979 deaths
Scientists from Hanover
20th-century German physicists
Immigrants to Australia
Immigrants to the United States
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https://en.wikipedia.org/wiki/Kavli%20Institute%20for%20Theoretical%20Physics
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The Kavli Institute for Theoretical Physics (KITP) is a research institute of the University of California, Santa Barbara. KITP is one of the most renowned institutes for theoretical physics in the world, and brings theorists in physics and related fields together to work on topics at the forefront of theoretical science.
The National Science Foundation has been the principal supporter of the institute since it was founded as the Institute for Theoretical Physics in 1979. In a 2007 article in the Proceedings of the National Academy of Sciences, KITP was given the highest impact index in a comparison of nonbiomedical research organizations across the U.S.
About
In the early 2000s, the institute, formerly known as the Institute for Theoretical Physics, or ITP, was named for the Norwegian-American physicist and businessman Fred Kavli, in recognition of his donation of $7.5 million to the institute.
Kohn Hall, which houses KITP, is located just beyond the Henley Gate at the East Entrance of the UCSB campus. The building was designed by the Driehaus Prize winner and New Classical architect Michael Graves, and a new wing designed by Graves was added in 2003–2004.
Members
The directors of the KITP since its beginning have been:
Walter Kohn, 1979–1984 (Nobel Prize in Chemistry, 1998)
Robert Schrieffer, 1984–1989 (Nobel Prize for Physics, 1972)
James S. Langer, 1989–1995 (Oliver Buckley Prize (APS), 1997)
James Hartle, 1995–1997 (Einstein Prize (APS), 2009)
David Gross, 1
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https://en.wikipedia.org/wiki/Sergey%20Lebedev%20%28scientist%29
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Sergey Alekseyevich Lebedev (; 2 November, 1902 – 3 July, 1974) was a Soviet scientist in the fields of electrical engineering and computer science, and designer of the first Soviet computers.
Biography
Lebedev was born in Nizhny Novgorod, Russian Empire. He graduated from Moscow Highest Technical School in 1928. From then until 1946 he worked at All-Union Electrotechnical Institute (formerly a division of MSTU) in Moscow and Kyiv. In 1939 he was awarded the degree of Doctor of Sciences for the development of the theory of "artificial stability" of electrical systems.
During World War II, Lebedev worked in the field of control automation of complex systems. His group designed a weapon-aiming stabilization system for tanks and an automatic guidance system for airborne missiles. To perform these tasks Lebedev developed an analog computer system to solve ordinary differential equations.
From 1946 to 1951 he headed the Kiev Electrotechnical Institute of the Ukrainian Academy of Sciences, working on improving the stability of electrical systems. For this work he received the Stalin (State) prize in 1950.
In 1948 Lebedev learned from foreign magazines that scientists in western countries were working on the design of electronic computers, although the details were secret. In the autumn of the same year he decided to focus the work of his laboratory on computer design. Lebedev's first computer, MESM, was fully completed by the end of 1951. In April 1953 the State commission acc
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https://en.wikipedia.org/wiki/For%20all%20practical%20purposes
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For all practical purposes (sometimes abbreviated FAPP) is a slogan used in physics to express a pragmatic attitude. A physical theory might be ambiguous in some ways — for example, being founded on untested assumptions or making unclear predictions about what might happen in certain situations — and yet still be successful in practice. Such a theory is said to be successful FAPP.
FAPP is also emerging as a valuable concept and approach in mathematics with a major title by the name For All Practical Purposes: Mathematical Literacy in Today's World.
There is also a profound joke about FAPP.
An elementary physics professor was teaching about how close you could get to the sun. He laid the foundation of heat and distance, and said that is as close as you can get FAPP. A boy asked, "what does that mean?"
The professor replied "All the girls in the room line up on the right side, and all of the boys line up on the left side. Now halve the distance between each side. Now do it again. After about five times of doing this, as their noses were touching, He said: You are all close enough for all practical purposes".
See also
Hand waving
Philosophy of science
Metaphysics
Limit (mathematics)
Phenomenalism
Empiricism
References
Rhetoric
Philosophy of physics
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https://en.wikipedia.org/wiki/Superpotential
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In theoretical physics, the superpotential is a function in supersymmetric quantum mechanics. Given a superpotential, two "partner potentials" are derived that can each serve as a potential in the Schrödinger equation. The partner potentials have the same spectrum, apart from a possible eigenvalue of zero, meaning that the physical systems represented by the two potentials have the same characteristic energies, apart from a possible zero-energy ground state.
One-dimensional example
Consider a one-dimensional, non-relativistic particle with a two state internal degree of freedom called "spin". (This is not quite the usual notion of spin encountered in nonrelativistic quantum mechanics, because "real" spin applies only to particles in three-dimensional space.) Let b and its Hermitian adjoint b† signify operators which transform a "spin up" particle into a "spin down" particle and vice versa, respectively. Furthermore, take b and b† to be normalized such that the anticommutator {b,b†} equals 1, and take that b2 equals 0. Let p represent the momentum of the particle and x represent its position with [x,p]=i, where we use natural units so that . Let W (the superpotential) represent an arbitrary differentiable function of x and define the supersymmetric operators Q1 and Q2 as
The operators Q1 and Q2 are self-adjoint. Let the Hamiltonian be
where W''' signifies the derivative of W. Also note that {Q1,Q2}=0. Under these circumstances, the above system is a toy model of N=2 supers
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https://en.wikipedia.org/wiki/Glossary%20of%20mathematical%20jargon
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The language of mathematics has a vast vocabulary of specialist and technical terms. It also has a certain amount of jargon: commonly used phrases which are part of the culture of mathematics, rather than of the subject. Jargon often appears in lectures, and sometimes in print, as informal shorthand for rigorous arguments or precise ideas. Much of this is common English, but with a specific non-obvious meaning when used in a mathematical sense.
Some phrases, like "in general", appear below in more than one section.
Philosophy of mathematics
abstract nonsenseA tongue-in-cheek reference to category theory, using which one can employ arguments that establish a (possibly concrete) result without reference to any specifics of the present problem. For that reason, it's also known as general abstract nonsense or generalized abstract nonsense.
canonicalA reference to a standard or choice-free presentation of some mathematical object (e.g., canonical map, canonical form, or canonical ordering). The same term can also be used more informally to refer to something "standard" or "classic". For example, one might say that Euclid's proof is the "canonical proof" of the infinitude of primes.
deepA result is called "deep" if its proof requires concepts and methods that are advanced beyond the concepts needed to formulate the result. For example, the prime number theorem — originally proved using techniques of complex analysis — was once thought to be a deep result until elementary pr
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https://en.wikipedia.org/wiki/Thomas%20H.%20Stix
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Thomas Howard Stix (July 12, 1924 – April 16, 2001) was an American physicist. Stix performed seminal work in plasma physics and wrote the first mathematical treatment of the field in 1962's The Theory of Plasma Waves.
History
Born in St. Louis, Missouri, on July 12, 1924, Stix grew up near Washington University. The Stix family owned Rice-Stix Inc., a dry goods firm that was among the city's largest businesses at the turn of the 20th century. It continued operations until the 1950s. His family home on Forsyth Boulevard was eventually donated to Washington University and is now the Stix International House.
Stix graduated from John Burroughs School and served in the U.S. Army as a radio expert in the Pacific theater during and after World War II. After the war, he obtained his bachelor's degree from Caltech in 1948 and his doctorate from Princeton in 1953.
He worked for Project Matterhorn, a secret U.S. study of nuclear fusion, and developed the Stix coil to contain gases that were heated to solar temperatures with electromagnetic waves. Stix's invention of the coil jump-started a period of intellectual productivity that revolutionized plasma heating research and whose influence is still felt in the field. Stix's 1975 paper “Fast Wave Heating of a Two-Component Plasma” remains one of the most cited papers ever published by the journal Nuclear Fusion.
Stix taught astrophysics at Princeton and did much of his research at the Princeton Plasma Physics Laboratory (see Model C
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https://en.wikipedia.org/wiki/Josef%20Pieprzyk
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Josef Pieprzyk (born 1949 in Poland) is currently a professor at Queensland University of Technology in Brisbane, Australia.
He has worked on cryptography, in particular the XSL attack. He collaborated in the invention of the LOKI and LOKI97 block ciphers and the HAVAL cryptographic hash function.
External links
Home page
1949 births
Living people
Modern cryptographers
20th-century Polish mathematicians
21st-century Polish mathematicians
Academic staff of Macquarie University
Academic staff of Queensland University of Technology
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https://en.wikipedia.org/wiki/131%20%28number%29
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131 (one hundred [and] thirty-one) is the natural number following 130 and preceding 132.
In mathematics
131 is a Sophie Germain prime, an irregular prime, the second 3-digit palindromic prime, and also a permutable prime with 113 and 311. It can be expressed as the sum of three consecutive primes, 131 = 41 + 43 + 47. 131 is an Eisenstein prime with no imaginary part and real part of the form . Because the next odd number, 133, is a semiprime, 131 is a Chen prime. 131 is an Ulam number.
131 is a full reptend prime in base 10 (and also in base 2). The decimal expansion of 1/131 repeats the digits 007633587786259541984732824427480916030534351145038167938931 297709923664122137404580152671755725190839694656488549618320 6106870229 indefinitely.
In the military
Convair C-131 Samaritan was an American military transport produced from 1954 to 1956
Strike Fighter Squadron (VFA-131) is a United States Navy F/A-18C Hornet fighter squadron stationed at Naval Air Station Oceana
Tiger 131 is a German Tiger I heavy tank captured in Tunisia by the British 48th Royal Tank Regiment during World War II
was a Mission Buenaventura-class fleet oiler during World War II
was a is a United States Navy ship during World War II
was a United States Navy
was a United States Navy General G. O. Squier-class transport ship during World War II
was a United States Navy during World War II
was a United States Navy during World War II
was a ship of the United States Navy during World War
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https://en.wikipedia.org/wiki/Phosphorylase
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In biochemistry, phosphorylases are enzymes that catalyze the addition of a phosphate group from an inorganic phosphate (phosphate+hydrogen) to an acceptor.
A-B + P A + P-B
They include allosteric enzymes that catalyze the production of glucose-1-phosphate from a glucan such as glycogen, starch or maltodextrin.
Phosphorylase is also a common name used for glycogen phosphorylase in honor of Earl W. Sutherland Jr., who in the late 1930s discovered it as the first phosphorylase.
Function
Phosphorylases should not be confused with phosphatases, which remove phosphate groups.
In more general terms, phosphorylases are enzymes that catalyze the addition of a phosphate group from an inorganic phosphate (phosphate + hydrogen) to an acceptor, not to be confused with a phosphatase (a hydrolase) or a kinase (a phosphotransferase). A phosphatase removes a phosphate group from a donor using water, whereas a kinase transfers a phosphate group from a donor (usually ATP) to an acceptor.
Types
The phosphorylases fall into the following categories:
Glycosyltransferases (EC 2.4)
Enzymes that break down glucans by removing a glucose residue (break O-glycosidic bond)
glycogen phosphorylase
starch phosphorylase
maltodextrin phosphorylase
Enzymes that break down nucleosides into their constituent bases and sugars (break N-glycosidic bond)
Purine nucleoside phosphorylase (PNPase)
Nucleotidyltransferases (EC 2.7.7)
Enzymes that have phosphorolytic 3' to 5' exoribonuclease activity (break phosp
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https://en.wikipedia.org/wiki/Geophysical%20Fluid%20Dynamics%20Laboratory
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The Geophysical Fluid Dynamics Laboratory (GFDL) is a laboratory in the National Oceanic and Atmospheric Administration (NOAA) Office of Oceanic and Atmospheric Research (OAR). The current director is Venkatachalam Ramaswamy. It is one of seven Research Laboratories within NOAA's OAR.
GFDL is engaged in comprehensive long-lead-time research to expand our scientific understanding of the physical and chemical processes that govern the behavior of the atmosphere and the oceans as complex fluid systems. These systems can be modeled mathematically and their phenomenology can be studied by computer simulation methods.
GFDL's accomplishments include the development of the first climate models to study global warming, the first comprehensive ocean prediction codes, and the first dynamical models with significant skill in hurricane track and intensity predictions. Much current research within the laboratory is focused around the development of Earth System Models for assessment of natural and human-induced climate change.
Accomplishments
The first global numerical simulations of the atmosphere — defining the basic structure of the numerical weather prediction and climate models that are still in use today throughout the world.
The first numerical simulation of the world ocean.
The initial definition and further elaborations of many of the central issues in global warming research, including water vapor feedback, polar amplification of temperature change, summer mid-continental dryn
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https://en.wikipedia.org/wiki/Gordon%20Gibson%20%28politician%2C%20born%201937%29
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Gordon Fullerton Gibson, (born 1937) is a political columnist, author, and politician in British Columbia, Canada. He is the son of Gordon Gibson Sr., who was a prominent businessman and Liberal Party politician in British Columbia in the 1950s.
He received a BA (Honours) in mathematics and physics at the University of British Columbia and an MBA from Harvard Business School, and he did research work at the London School of Economics.
Gibson served as an assistant to the federal Minister of Northern Affairs from 1963 to 1968, and was a special assistant to Prime Minister Pierre Trudeau from 1968 to 1972. In the 1972 federal election, he ran as the Liberal candidate in Vancouver South, but lost to Progressive Conservative candidate John Fraser by 3,000 votes.
In 1974, Gibson won a by-election to the Legislative Assembly of British Columbia in the riding of North Vancouver-Capilano under the Liberal banner. The following year, three Liberal MLAs defected to the Social Credit Party three months before that year's general election, leaving Gibson and party leader David Anderson as the only two Liberals in the legislature. Anderson declined to be renominated to the leadership, and Gibson was approached to lead the party into the election. He was the only Liberal elected that year. He remained party leader until 1979, when he resigned to run again for a seat in the federal House of Commons, in the riding of North Vancouver-Burnaby. He was defeated in both the 1979 and 1980
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https://en.wikipedia.org/wiki/Irwin%20Rose
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Irwin Allan Rose (July 16, 1926 – June 2, 2015) was an American biologist. Along with Aaron Ciechanover and Avram Hershko, he was awarded the 2004 Nobel Prize in Chemistry for the discovery of ubiquitin-mediated protein degradation.
Education and early life
Rose was born in Brooklyn, New York, into a secular Jewish family, the son of Ella (Greenwald) and Harry Royze, who owned a flooring store. Rose attended Washington State University for one year prior to serving in the Navy during World War II. Upon returning from the war he received his Bachelor of Science degree in 1948 and his PhD in biochemistry in 1952, both from the University of Chicago. He did his post-doctoral studies at NYU.
Career and research
Rose served on the faculty of Yale School of Medicine's department of biochemistry from 1954 to 1963. He then joined the Fox Chase Cancer Center in 1963 and stayed there until he retired in 1995. He joined University of Pennsylvania during the 1970s and served as a Professor of Physical Biochemistry. He was a distinguished professor-in-residence in the Department of Physiology and Biophysics at the University of California, Irvine School of Medicine at the time his Nobel Prize was announced in 2004.
Irwin (Ernie) trained several postdoctoral research fellows while at the Fox Chase Cancer Center in Philadelphia. These included Art Haas, the first to see Ubiquitin chains, Keith Wilkinson, the one to first identify APF-1 as Ubiquitin, and Cecile Pickart.
Published work
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https://en.wikipedia.org/wiki/Avram%20Hershko
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Avram Hershko (, ; born December 31, 1937) is a Hungarian-Israeli biochemist who received the Nobel Prize in Chemistry in 2004.
Biography
He was born Herskó Ferenc in Karcag, Hungary, into a Jewish family, the son of Shoshana/Margit 'Manci' (née Wulc) and Moshe Hershko, both teachers.
During the Second World War, his father was forced into labor service in the Hungarian army and then taken as a prisoner by the Soviet Army. For years, Avram's family didn't known anything about what had happened to his father. Avram, his mother and older brother were put in a ghetto in Szolnok. During the final days of the ghetto, most Jews were sent to be murdered in Auschwitz, but Avram and his family managed to board trains that took them to a concentration camp in Austria, where they were forced into labor until the end of the war. Avram and his mother survived the war and returned to their home. His father returned as well, 4 years after they had last seen him.
Hershko and his family emigrated to Israel in 1950 and settled in Jerusalem. He received his MD in 1965 and his PhD in 1969 from the Hebrew University of Jerusalem-Hadassah Medical Center. He was a postdoctoral scholar at the University of California, San Francisco. He is currently a Distinguished Professor at the Rappaport Faculty of Medicine at the Technion in Haifa and a Distinguished Adjunct Professor at the New York University Grossman School of Medicine.
Along with Aaron Ciechanover and Irwin Rose, he was awarded the 2004
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https://en.wikipedia.org/wiki/Aaron%20Ciechanover
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Aaron Ciechanover ( ; ; born October 1, 1947) is an Israeli biologist who won the Nobel Prize in Chemistry for characterizing the method that cells use to degrade and recycle proteins using ubiquitin.
Biography
Early life
Ciechanover was born in Haifa, British Mandate of Palestine on 1 October 1947 into a Jewish family. He is the son of Bluma (Lubashevsky), a teacher of English, and Yitzhak Ciechanover, an office worker. His mother and father supported the Zionist movement and immigrated to Israel from Poland in the 1920s.
Education
He earned a master's degree in science in 1971 and graduated from Hadassah Medical School in Jerusalem in 1974. He received his doctorate in biochemistry in 1981 from the Technion – Israel Institute of Technology in Haifa before conducting postdoctoral research in the laboratory of Harvey Lodish at the Whitehead Institute at MIT from 1981 to 1984.
Recent
Ciechanover is currently a Technion Distinguished Research Professor in the Ruth and Bruce Rappaport Faculty of Medicine and Research Institute at the Technion. He is a member of the Israel Academy of Sciences and Humanities, the Pontifical Academy of Sciences, the National Academy of Sciences of Ukraine, the Russian Academy of Sciences and is a foreign associate of the United States National Academy of Sciences. In 2008, he was a visiting Distinguished Chair Professor at NCKU, Taiwan. As part of Shenzhen's 13th Five-Year Plan funding research in emerging technologies and opening "Nobel lau
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https://en.wikipedia.org/wiki/Comb%20filter
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In signal processing, a comb filter is a filter implemented by adding a delayed version of a signal to itself, causing constructive and destructive interference. The frequency response of a comb filter consists of a series of regularly spaced notches in between regularly spaced peaks (sometimes called teeth) giving the appearance of a comb.
Comb filters exist in two forms, feedforward and feedback; which refer to the direction in which signals are delayed before they are added to the input.
Comb filters may be implemented in discrete time or continuous time forms which are very similar.
Applications
Comb filters are employed in a variety of signal processing applications, including:
Cascaded integrator–comb (CIC) filters, commonly used for anti-aliasing during interpolation and decimation operations that change the sample rate of a discrete-time system.
2D and 3D comb filters implemented in hardware (and occasionally software) in PAL and NTSC analog television decoders, reduce artifacts such as dot crawl.
Audio signal processing, including delay, flanging, physical modelling synthesis and digital waveguide synthesis. If the delay is set to a few milliseconds, a comb filter can model the effect of acoustic standing waves in a cylindrical cavity or in a vibrating string.
In astronomy the astro-comb promises to increase the precision of existing spectrographs by nearly a hundredfold.
In acoustics, comb filtering can arise as an unwanted artifact. For instance, two loud
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https://en.wikipedia.org/wiki/DNT
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DNT may refer to:
Science, technology and medicine
Chemistry
Dermonecrotic toxin, a toxin
Dinitrotoluene, a chemical precursor to TNT
Medicine
Double-negative T cell, a thymocyte in an early stage of development
Dysembryoplastic neuroepithelial tumour, a type of brain tumour
Computing
Do Not Track, a proposed HTTP header, to disable tracking by web services
Places
Dallas North Tollway, Texas, USA
Dent railway station, by National Rail station code
Other uses
Denotified tribes of India
Norwegian Trekking Association (Norwegian: Den Norske Turistforening)
Duluth News Tribune, a newspaper in Duluth, Minnesota, USA
Druk Nyamrup Tshogpa, a political party in Bhutan
See also
Trinitrotoluene (TNT), an explosive chemical compound
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https://en.wikipedia.org/wiki/Ethoxylation
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In organic chemistry, ethoxylation is a chemical reaction in which ethylene oxide () adds to a substrate. It is the most widely practiced alkoxylation, which involves the addition of epoxides to substrates.
In the usual application, alcohols and phenols are converted into where n ranges from 1 to 10. Such compounds are called alcohol ethoxylates. Alcohol ethoxylates are often converted to related species called ethoxysulfates. Alcohol ethoxylates and ethoxysulfates are surfactants, used widely in cosmetic and other commercial products. The process is of great industrial significance, with more than 2,000,000 metric tons of various ethoxylates produced worldwide in 1994.
Production
The process was developed at the Ludwigshafen laboratories of IG Farben by Conrad Schöller and during the 1930s.
Alcohol ethoxylates
Industrial ethoxylation is primarily performed upon alcohols. Lower alcohols react to give glycol ethers which are commonly used as solvents, while longer fatty alcohols are converted to fatty alcohol ethoxylates (FAE's), which are a common form of nonionic surfactant. The reaction typically proceeds by blowing ethylene oxide through the alcohol at 180 °C and under 1-2 bar of pressure, with potassium hydroxide (KOH) serving as a catalyst. The process is highly exothermic (ΔH = -92 kJ/mol of ethylene oxide reacted) and requires careful control to avoid a potentially disastrous thermal runaway.
The starting materials are usually primary alcohols as they tend to r
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https://en.wikipedia.org/wiki/133%20%28number%29
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133 (one hundred [and] thirty-three) is the natural number following 132 and preceding 134.
In mathematics
133 is an n whose divisors (excluding n itself) added up divide φ(n). It is an octagonal number and a happy number.
133 is a Harshad number, because it is divisible by the sum of its digits.
133 is a repdigit in base 11 (111) and base 18 (77), whilst in base 20 it is a cyclic number formed from the reciprocal of the number three.
133 is a semiprime: a product of two prime numbers, namely 7 and 19. Since those prime factors are Gaussian primes, this means that 133 is a Blum integer.
133 is the number of compositions of 13 into distinct parts.
In the military
Douglas C-133 Cargomaster was a United States cargo aircraft built between 1956 and 1961
is a heavy landing craft which launched in 1972
was a United States Navy Mission Buenaventura-class fleet oilers during World War II
was a United States Navy during World War II
was a United States Navy during World War II
was a United States Navy General G. O. Squier-class transport ship during World War II
was a United States Navy during World War I
was a United States Navy during World War II
was a United States Navy during World War II
was a United States Navy S-class submarine during World War II
was a United States Navy during World War II
was a United States Navy heavy cruiser during the Korean War
Frontstalag 133 was a temporary German prisoner of war camp during World War II located n
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https://en.wikipedia.org/wiki/Covering%20problems
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In combinatorics and computer science, covering problems are computational problems that ask whether a certain combinatorial structure 'covers' another, or how large the structure has to be to do that. Covering problems are minimization problems and usually integer linear programs, whose dual problems are called packing problems.
The most prominent examples of covering problems are the set cover problem, which is equivalent to the hitting set problem, and its special cases, the vertex cover problem and the edge cover problem.
Covering Problems allows the covering primitives to overlap, If you want to cover something with primitives that don't overlap is called Decomposition_(disambiguation)
General linear programming formulation
In the context of linear programming, one can think of any minimization linear program as a covering problem if the coefficients in the constraint matrix, the objective function, and right-hand side are nonnegative. More precisely, consider the following general integer linear program:
Such an integer linear program is called a covering problem if for all and .
Intuition: Assume having types of object and each object of type has an associated cost of . The number indicates how many objects of type we buy. If the constraints are satisfied, it is said that is a covering (the structures that are covered depend on the combinatorial context). Finally, an optimal solution to the above integer linear program is a covering of minimal cost.
Kinds
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https://en.wikipedia.org/wiki/Canonicalization
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In computer science, canonicalization (sometimes standardization or normalization) is a process for converting data that has more than one possible representation into a "standard", "normal", or canonical form. This can be done to compare different representations for equivalence, to count the number of distinct data structures, to improve the efficiency of various algorithms by eliminating repeated calculations, or to make it possible to impose a meaningful sorting order.
Usage cases
Filenames
Files in file systems may in most cases be accessed through multiple filenames. For instance in Unix-like systems, the string "/./" can be replaced by "/". In the C standard library, the function realpath() performs this task. Other operations performed by this function to canonicalize filenames are the handling of /.. components referring to parent directories, simplification of sequences of multiple slashes, removal of trailing slashes, and the resolution of symbolic links.
Canonicalization of filenames is important for computer security. For example, a web server may have a restriction that only files under the cgi directory C:\inetpub\wwwroot\cgi-bin may be executed. This rule is enforced by checking that the path starts with C:\inetpub\wwwroot\cgi-bin\ and only then executing it. While the file C:\inetpub\wwwroot\cgi-bin\..\..\..\Windows\System32\cmd.exe initially appears to be in the cgi directory, it exploits the .. path specifier to traverse back up the directory hierar
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https://en.wikipedia.org/wiki/Projection-valued%20measure
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In mathematics, particularly in functional analysis, a projection-valued measure (PVM) is a function defined on certain subsets of a fixed set and whose values are self-adjoint projections on a fixed Hilbert space. Projection-valued measures are formally similar to real-valued measures, except that their values are self-adjoint projections rather than real numbers. As in the case of ordinary measures, it is possible to integrate complex-valued functions with respect to a PVM; the result of such an integration is a linear operator on the given Hilbert space.
Projection-valued measures are used to express results in spectral theory, such as the important spectral theorem for self-adjoint operators, in which case the PVM is sometimes referred to as the spectral measure. The Borel functional calculus for self-adjoint operators is constructed using integrals with respect to PVMs. In quantum mechanics, PVMs are the mathematical description of projective measurements. They are generalized by positive operator valued measures (POVMs) in the same sense that a mixed state or density matrix generalizes the notion of a pure state.
Formal definition
A projection-valued measure on a measurable space
, where is a σ-algebra of subsets of , is a mapping from to the set of self-adjoint projections on a Hilbert space (i.e. the orthogonal projections) such that
(where is the identity operator of ) and for every , the following function
is a complex measure on (that is, a comp
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https://en.wikipedia.org/wiki/Swarm%20robotics
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Swarm robotics is an approach to the coordination of multiple robots as a system which consist of large numbers of mostly simple physical robots. ″In a robot swarm, the collective behavior of the robots results from local interactions between the robots and between the robots and the environment in which they act.″ It is supposed that a desired collective behavior emerges from the interactions between the robots and interactions of robots with the environment. This approach emerged on the field of artificial swarm intelligence, as well as the biological studies of insects, ants and other fields in nature, where swarm behaviour occurs.
Definition
The research of swarm robotics is to study the design of robots, their physical body and their controlling behaviours. It is inspired but not limited by the emergent behaviour observed in social insects, called swarm intelligence. Relatively simple individual rules can produce a large set of complex swarm behaviours. A key component is the communication between the members of the group that build a system of constant feedback. The swarm behaviour involves constant change of individuals in cooperation with others, as well as the behaviour of the whole group.
Unlike distributed robotic systems in general, swarm robotics emphasizes a large number of robots, and promotes scalability, for instance by using only local communication. That local communication for example can be achieved by wireless transmission systems, like radio frequency
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https://en.wikipedia.org/wiki/Nerve%20%28disambiguation%29
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A nerve is a part of the peripheral nervous system.
Nerve or Nerves may also refer to:
Mathematics
Nerve of a covering, a construction in mathematical topology
Nerve (category theory), a construction in category theory
Film and television
Nerves (film), a 1919 film by the Austrian director and novelist Robert Reinert
"Nerve" (Farscape), a 2000 episode of Farscape
Nerve (2013 film), a 2013 Australian psychological thriller film
Nerve (2016 film), a 2016 American drama thriller film
Books
Nerve (magazine), a Liverpool-based arts and social issues magazine
Nerve (Francis novel), a 1964 novel by Dick Francis
Nerve (Ryan novel), a 2012 young adult thriller by Jeanne Ryan
Computing
Nerve Software, a video game developer
Nerve (website), a website and magazine
Music
Artists
The Nerves, an American power pop band
Nerve, an American band founded by Jojo Mayer
Nerve, an industrial rock band that Junkie XL was a member of
Songs
"nerve", by Bis from Brand-new idol Society, 2011
"Nerve", by Blindside from Blindside, 1997
"Nerve", by Charlotte Church from Two, 2013
"Nerve", by Don Broco from Automatic, 2015
"Nerve", by Half Moon Run from Dark Eyes, 2012
"Nerve", by Soilwork from Stabbing the Drama, 2005
"Nerve", by The Story So Far from The Story So Far, 2015
"Nerves", by Bauhaus from In the Flat Field, 1980
"Nerves", by Maths Class, 2008
"Nerves", by Silkworm from Firewater, 1996
"The Nerve", by George Strait from Carrying Your Love with Me, 1997
"The
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https://en.wikipedia.org/wiki/HSAB%20theory
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HSAB concept is a jargon for "hard and soft (Lewis) acids and bases". HSAB is widely used in chemistry for explaining stability of compounds, reaction mechanisms and pathways. It assigns the terms 'hard' or 'soft', and 'acid' or 'base' to chemical species. 'Hard' applies to species which are small, have high charge states (the charge criterion applies mainly to acids, to a lesser extent to bases), and are weakly polarizable. 'Soft' applies to species which are big, have low charge states and are strongly polarizable.
The theory is used in contexts where a qualitative, rather than quantitative, description would help in understanding the predominant factors which drive chemical properties and reactions. This is especially so in transition metal chemistry, where numerous experiments have been done to determine the relative ordering of ligands and transition metal ions in terms of their hardness and softness.
HSAB theory is also useful in predicting the products of metathesis reactions. In 2005 it was shown that even the sensitivity and performance of explosive materials can be explained on basis of HSAB theory.
Ralph Pearson introduced the HSAB principle in the early 1960s as an attempt to unify inorganic and organic reaction chemistry.
Theory
Essentially, the theory states that soft acids react faster and form stronger bonds with soft bases, whereas hard acids react faster and form stronger bonds with hard bases, all other factors being equal. The classification in the
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https://en.wikipedia.org/wiki/Joseph%20Clinton
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Joseph D. Clinton had a long professional association with Buckminster Fuller. In 1970, Clinton worked in the School of Technology at Southern Illinois University, where Fuller taught, and researched papers on the mathematics involved with geodesics, contracted and published by NASA in 1971. Some five years later, Clinton founded Clinton International Design Consultants, an interdisciplinary design and consulting firm based on the philosophy of what he termed "the structures field of Design Science." Clinton’s work has specialised in environmentally sensitive design systems, incorporating elements such as solar and wind structures and systems. His firm did work contributing to such structures as the Omni Max Theater for Expo 86 in Vancouver, British Columbia, Canada, and the Epcot Center’s Horizon Omnisphere Theater.
References
Di Carlo, Biagio (May 2008). "The wooden roofs of Leonardo and new structural research". Nexus Network Journal 10 (1). ISSN 1590-5896.
Fuller, R. Buckminster (1999). Krausse, Joachim; Lichtenstein, Claude. eds. Your private sky: R. Buckminster Fuller, the art of design science. Lars Müller. .
External links
Don Michel 'Insight' radio interview with Joe Clinton, August 11, 1966
Living people
Year of birth missing (living people)
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https://en.wikipedia.org/wiki/Recursive%20definition
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In mathematics and computer science, a recursive definition, or inductive definition, is used to define the elements in a set in terms of other elements in the set (Aczel 1977:740ff). Some examples of recursively-definable objects include factorials, natural numbers, Fibonacci numbers, and the Cantor ternary set.
A recursive definition of a function defines values of the function for some inputs in terms of the values of the same function for other (usually smaller) inputs. For example, the factorial function is defined by the rules
This definition is valid for each natural number , because the recursion eventually reaches the base case of 0. The definition may also be thought of as giving a procedure for computing the value of the function , starting from and proceeding onwards with etc.
The recursion theorem states that such a definition indeed defines a function that is unique. The proof uses mathematical induction.
An inductive definition of a set describes the elements in a set in terms of other elements in the set. For example, one definition of the set of natural numbers is:
1 is in
If an element n is in then is in
is the intersection of all sets satisfying (1) and (2).
There are many sets that satisfy (1) and (2) – for example, the set satisfies the definition. However, condition (3) specifies the set of natural numbers by removing the sets with extraneous members. Note that this definition assumes that is contained in a larger set (such as the set of
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https://en.wikipedia.org/wiki/Complete%20variety
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In mathematics, in particular in algebraic geometry, a complete algebraic variety is an algebraic variety , such that for any variety the projection morphism
is a closed map (i.e. maps closed sets onto closed sets). This can be seen as an analogue of compactness in algebraic geometry: a topological space is compact if and only if the above projection map is closed with respect to topological products.
The image of a complete variety is closed and is a complete variety. A closed subvariety of a complete variety is complete.
A complex variety is complete if and only if it is compact as a complex-analytic variety.
The most common example of a complete variety is a projective variety, but there do exist complete non-projective varieties in dimensions 2 and higher. While any complete nonsingular surface is projective, there exist nonsingular complete varieties in dimension 3 and higher which are not projective. The first examples of non-projective complete varieties were given by Masayoshi Nagata and Heisuke Hironaka. An affine space of positive dimension is not complete.
The morphism taking a complete variety to a point is a proper morphism, in the sense of scheme theory. An intuitive justification of "complete", in the sense of "no missing points", can be given on the basis of the valuative criterion of properness, which goes back to Claude Chevalley.
See also
Chow's lemma
Theorem of the cube
Fano variety
Notes
References
Sources
Section II.4 of
Chapter 7 of
Sect
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https://en.wikipedia.org/wiki/University%20of%20Bia%C5%82ystok
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The University of Bialystok is the largest university in the north-eastern region of Poland, educating in various fields of study, including humanities, social and natural sciences and mathematics. It has nine faculties, including a foreign one in Vilnius. Four faculties have been awarded the highest scientific category “A”. The University of Bialystok has the right to confer doctoral degrees in ten fields, as well as postdoctoral degrees in law, economics, chemistry, biology, history and physics.
Over 13,000 students are being educated in 31 fields of study, including doctoral studies and postgraduate studies. The university employs nearly 800 academics, almost 200 professors among them.
Every year the university carries out approximately 60 research projects, financed from domestic and foreign funds; it also benefits from the structural funds. Among the university's many accomplishments are its participation in 6th and 7th Framework Programme for Research, Technological Development and Demonstration, Horizon 2020, Comenius and Aspera as well as the DAPHNE III programme.
History
University of Białystok was opened on June 19, 1997. The university was established as a result of a transformation of the Branch of the University of Warsaw in Białystok after 29 years of its existence.
The university has a branch in Vilnius, Lithuania.
Foundation
The University of Bialystok Foundation, Universitas Bialostocensis () - independent, non-profit, non-governmental organization loca
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https://en.wikipedia.org/wiki/Muirhead%27s%20Inequality
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In mathematics, Muirhead's inequality, named after Robert Franklin Muirhead, also known as the "bunching" method, generalizes the inequality of arithmetic and geometric means.
Preliminary definitions
a-mean
For any real vector
define the "a-mean" [a] of positive real numbers x1, ..., xn by
where the sum extends over all permutations σ of { 1, ..., n }.
When the elements of a are nonnegative integers, the a-mean can be equivalently defined via the monomial symmetric polynomial as
where ℓ is the number of distinct elements in a, and k1, ..., kℓ are their multiplicities.
Notice that the a-mean as defined above only has the usual properties of a mean (e.g., if the mean of equal numbers is equal to them) if . In the general case, one can consider instead , which is called a Muirhead mean.
Examples
For a = (1, 0, ..., 0), the a-mean is just the ordinary arithmetic mean of x1, ..., xn.
For a = (1/n, ..., 1/n), the a-mean is the geometric mean of x1, ..., xn.
For a = (x, 1 − x), the a-mean is the Heinz mean.
The Muirhead mean for a = (−1, 0, ..., 0) is the harmonic mean.
Doubly stochastic matrices
An n × n matrix P is doubly stochastic precisely if both P and its transpose PT are stochastic matrices. A stochastic matrix is a square matrix of nonnegative real entries in which the sum of the entries in each column is 1. Thus, a doubly stochastic matrix is a square matrix of nonnegative real entries in which the sum of the entries in each row and the sum of the entr
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https://en.wikipedia.org/wiki/Supramolecular%20chemistry
|
Supramolecular chemistry refers to the branch of chemistry concerning chemical systems composed of a discrete number of molecules. The strength of the forces responsible for spatial organization of the system range from weak intermolecular forces, electrostatic charge, or hydrogen bonding to strong covalent bonding, provided that the electronic coupling strength remains small relative to the energy parameters of the component. While traditional chemistry concentrates on the covalent bond, supramolecular chemistry examines the weaker and reversible non-covalent interactions between molecules. These forces include hydrogen bonding, metal coordination, hydrophobic forces, van der Waals forces, pi–pi interactions and electrostatic effects.
Important concepts advanced by supramolecular chemistry include molecular self-assembly, molecular folding, molecular recognition, host–guest chemistry, mechanically-interlocked molecular architectures, and dynamic covalent chemistry. The study of non-covalent interactions is crucial to understanding many biological processes that rely on these forces for structure and function. Biological systems are often the inspiration for supramolecular research.
Gallery
History
The existence of intermolecular forces was first postulated by Johannes Diderik van der Waals in 1873. However, Nobel laureate Hermann Emil Fischer developed supramolecular chemistry's philosophical roots. In 1894, Fischer suggested that enzyme–substrate interactions take the fo
|
https://en.wikipedia.org/wiki/Weill
|
Weill is an educational institution affiliated with Cornell University, named after Sanford I. Weill and may refer to:
Weill Institute for Cell and Molecular Biology, research institute located on Cornell University's Ithaca, NY campus
Weill Medical College of Cornell University, medical school located in New York City
Weill Cornell Graduate School of Medical Sciences, graduate college for biomedical sciences located in New York City
Weill Medical College in Qatar, medical school located in Qatar
See also
Weil (disambiguation)
Weil (surname), also listing people with the surname "Weill"
|
https://en.wikipedia.org/wiki/ROOT
|
ROOT is an object-oriented computer program and library developed by CERN. It was originally designed for particle physics data analysis and contains several features specific to the field, but it is also used in other applications such as astronomy and data mining. The latest minor release is 6.28, as of 2023-02-03.
Description
CERN maintained the CERN Program Library written in FORTRAN for many years. Its development and maintenance were discontinued in 2003 in favour of ROOT, which is written in the C++ programming language.
ROOT development was initiated by René Brun and Fons Rademakers in 1994. Some parts are published under the GNU Lesser General Public License (LGPL) and others are based on GNU General Public License (GPL) software, and are thus also published under the terms of the GPL. It provides platform independent access to a computer's graphics subsystem and operating system using abstract layers. Parts of the abstract platform are: a graphical user interface and a GUI builder, container classes, reflection, a C++ script and command line interpreter (CINT in version 5, cling in version 6), object serialization and persistence.
The packages provided by ROOT include those for
Histogramming and graphing to view and analyze distributions and functions,
curve fitting (regression analysis) and minimization of functionals,
statistics tools used for data analysis,
matrix algebra,
four-vector computations, as used in high energy physics,
standard mathematical f
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https://en.wikipedia.org/wiki/Equivalent%20circuit
|
In electrical engineering, an equivalent circuit refers to a theoretical circuit that retains all of the electrical characteristics of a given circuit. Often, an equivalent circuit is sought that simplifies calculation, and more broadly, that is a simplest form of a more complex circuit in order to aid analysis. In its most common form, an equivalent circuit is made up of linear, passive elements. However, more complex equivalent circuits are used that approximate the nonlinear behavior of the original circuit as well. These more complex circuits often are called macromodels of the original circuit. An example of a macromodel is the Boyle circuit for the 741 operational amplifier.
Examples
Thévenin and Norton equivalents
One of linear circuit theory's most surprising properties relates to the ability to treat any two-terminal circuit no matter how complex as behaving as only a source and an impedance, which have either of two simple equivalent circuit forms:
Thévenin equivalent – Any linear two-terminal circuit can be replaced by a single voltage source and a series impedance.
Norton equivalent – Any linear two-terminal circuit can be replaced by a current source and a parallel impedance.
However, the single impedance can be of arbitrary complexity (as a function of frequency) and may be irreducible to a simpler form.
DC and AC equivalent circuits
In linear circuits, due to the superposition principle, the output of a circuit is equal to the sum of the output due to its D
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https://en.wikipedia.org/wiki/Apollonian%20gasket
|
In mathematics, an Apollonian gasket or Apollonian net is a fractal generated by starting with a triple of circles, each tangent to the other two, and successively filling in more circles, each tangent to another three. It is named after Greek mathematician Apollonius of Perga.
Construction
The construction of the Apollonian gasket starts with three circles , , and (black in the figure), that are each tangent to the other two, but that do not have a single point of triple tangency. These circles may be of different sizes to each other, and it is allowed for two to be inside the third, or for all three to be outside each other. As Apollonius discovered, there exist two more circles and (red) that are tangent to all three of the original circles – these are called Apollonian circles. These five circles are separated from each other by six curved triangular regions, each bounded by the arcs from three pairwise-tangent circles. The construction continues by adding six more circles, one in each of these six curved triangles, tangent to its three sides. These in turn create 18 more curved triangles, and the construction continues by again filling these with tangent circles, ad infinitum.
Continued stage by stage in this way, the construction adds new circles at stage , giving a total of circles after stages. In the limit, this set of circles is an Apollonian gasket. In it, each pair of tangent circles has an infinite Pappus chain of circles tangent to both circles in the p
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https://en.wikipedia.org/wiki/N.M.A.M.%20Institute%20of%20Technology
|
N.M.A.M. Institute of Technology (NMAMIT), full name Nitte Mahalinga Adyanthaya Memorial Institute of Technology, is a deemed engineering college in Nitte, Karnataka, India. It was established in 1986, with programs in electronics and communication computer science, mechanical engineering, civil engineering and electrical engineering.
Currently it offers BTech programs in Artificial Intelligence & Machine Learning,Artificial Intelligence and Datascience,Biotechnology Engineering, Civil Engineering, Computer & Communications Engineering, Computer Science and Engineering, Electronics and Communication Engineering, Electrical and Electronics Engineering, Information Science and Engineering, Mechanical Engineering and Robotics & Artificial Intelligence.
The college is run by the Nitte Education Trust, which was founded in 1979 by Justice Kowdoor Sadananda Hegde, former Chief Justice of the Supreme Court and former Speaker of the Lok Sabha. The college was affiliated to the Visvesvaraya Technological University, Belgaum. It received the autonomous status in 2007-08. And now has been constituent college of Nitte University, Mangalore since June 2022.
Rankings
N.M.A.M. Institute of Technology was ranked 175 among engineering colleges by the National Institutional Ranking Framework (NIRF) in 2022.
Campus
The college is situated in the village of Nitte in an interior area of Udupi district. It is around from Mangalore. The various departments, laboratories, and hostels are loca
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https://en.wikipedia.org/wiki/Mark%20P.%20Brown
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Mark P. Brown (born November 15, 1956, Columbus, Ohio) is a veteran of the Ohio National Guard, a former construction/civil engineering technician and former political candidate of the Democratic Party. He was the party's 2002 and 2004 nominee to challenge incumbent Republican U.S. Representative Deborah Pryce. Pryce won both elections, gaining 108,193 votes to Brown's 54,286 in 2002, and 189,024 votes to Brown's 117,324 in 2004.
2004 Democratic Party primary election results:
See also:
Election Results, U.S. Representative from Ohio, 15th District
References
Living people
1950s births
Ohio Democrats
Engineers from Ohio
Politicians from Columbus, Ohio
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https://en.wikipedia.org/wiki/Quasidihedral%20group
|
In mathematics, the quasi-dihedral groups, also called semi-dihedral groups, are certain non-abelian groups of order a power of 2. For every positive integer n greater than or equal to 4, there are exactly four isomorphism classes of non-abelian groups of order 2n which have a cyclic subgroup of index 2. Two are well known, the generalized quaternion group and the dihedral group. One of the remaining two groups is often considered particularly important, since it is an example of a 2-group of maximal nilpotency class. In Bertram Huppert's text Endliche Gruppen, this group is called a "Quasidiedergruppe". In Daniel Gorenstein's text, Finite Groups, this group is called the "semidihedral group". Dummit and Foote refer to it as the "quasidihedral group"; we adopt that name in this article. All give the same presentation for this group:
.
The other non-abelian 2-group with cyclic subgroup of index 2 is not given a special name in either text, but referred to as just G or Mm(2). When this group has order 16, Dummit and Foote refer to this group as the "modular group of order 16", as its lattice of subgroups is modular. In this article this group will be called the modular maximal-cyclic group of order . Its presentation is:
.
Both these two groups and the dihedral group are semidirect products of a cyclic group <r> of order 2n−1 with a cyclic group <s> of order 2. Such a non-abelian semidirect product is uniquely determined by an element of order 2 in the group of units
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https://en.wikipedia.org/wiki/Laver%20table
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In mathematics, Laver tables (named after Richard Laver, who discovered them towards the end of the 1980s in connection with his works on set theory) are tables of numbers that have certain properties of algebraic and combinatorial interest. They occur in the study of racks and quandles.
Definition
For any nonnegative integer n, the n-th Laver table is the 2n × 2n table whose entry in the cell at row p and column q (1 ≤ p,q ≤ 2n) is defined as
where is the unique binary operation that satisfies the following two equations for all p, q in {1,...,2n}:
and
Note: Equation () uses the notation to mean the unique member of {1,...,2n} congruent to x modulo 2n.
Equation () is known as the (left) self-distributive law, and a set endowed with any binary operation satisfying this law is called a shelf. Thus, the n-th Laver table is just the multiplication table for the unique shelf ({1,...,2n}, ) that satisfies Equation ().
Examples: Following are the first five Laver tables, i.e. the multiplication tables for the shelves ({1,...,2n}, ), n = 0, 1, 2, 3, 4:
There is no known closed-form expression to calculate the entries of a Laver table directly, but Patrick Dehornoy provides a simple algorithm for filling out Laver tables.
Properties
For all p, q in {1,...,2n}: .
For all p in {1,...,2n}: is periodic with period πn(p) equal to a power of two.
For all p in {1,...,2n}: is strictly increasing from to .
For all p,q:
Are the first-row periods unbounded?
Looking at
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https://en.wikipedia.org/wiki/Evolutionary%20robotics
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Evolutionary robotics is an embodied approach to Artificial Intelligence (AI) in which robots are automatically designed using Darwinian principles of natural selection. The design of a robot, or a subsystem of a robot such as a neural controller, is optimized against a behavioral goal (e.g. run as fast as possible). Usually, designs are evaluated in simulations as fabricating thousands or millions of designs and testing them in the real world is prohibitively expensive in terms of time, money, and safety.
An evolutionary robotics experiment starts with a population of randomly generated robot designs. The worst performing designs are discarded and replaced with mutations and/or combinations of the better designs. This evolutionary algorithm continues until a prespecified amount of time elapses or some target performance metric is surpassed.
Evolutionary robotics methods are particularly useful for engineering machines that must operate in environments in which humans have limited intuition (nanoscale, space, etc.). Evolved simulated robots can also be used as scientific tools to generate new hypotheses in biology and cognitive science, and to test old hypothesis that require experiments that have proven difficult or impossible to carry out in reality.
History
In the early 1990s, two separate European groups demonstrated different approaches to the evolution of robot control systems. Dario Floreano and Francesco Mondada at EPFL evolved controllers for the Khepera robot. Ad
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https://en.wikipedia.org/wiki/Glycosyl
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In organic chemistry, a glycosyl group is a univalent free radical or substituent structure obtained by removing the hydroxyl () group from the hemiacetal () group found in the cyclic form of a monosaccharide and, by extension, of a lower oligosaccharide.
Glycosyl also reacts with inorganic acids, such as phosphoric acid, forming an ester such as glucose 1-phosphate.
Examples
In cellulose, glycosyl groups link together 1,4-β-D-glucosyl units to form chains of (1,4-β-D-glucosyl)n.
Other examples include ribityl in 6,7-Dimethyl-8-ribityllumazine, and glycosylamines.
Alternative substituent groups
Instead of the hemiacetal hydroxyl group, a hydrogen atom can be removed to form a substituent, for example the hydrogen from the C3 hydroxyl of a glucose molecule. Then the substituent is called D-glucopyranos-3-O-yl as it appears in the name of the drug Mifamurtide.
Recent detection of the Au3+ in living organism was possible through the use of C-glycosyl pyrene, where it's permeability through cell membrane and fluorescence properties were used to detect Au3+.
See also
Acyl group
References
Substituents
Biomolecules
Monosaccharides
Oligosaccharides
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https://en.wikipedia.org/wiki/Dogfish
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Dogfish may refer to:
Biology
Dogfish sharks (Squalidae), a family of sharks
Spiny dogfish (Squalus acanthias), best known species of dogfish sharks
Pacific spiny dogfish (Squalus suckleyi), the most abundant species of dogfish sharks
Catshark (Scyliorhinidae), a family of ground sharks including species called dogfish
Chain dogfish (Scyluoirrhinus reteiter), a biofluorescent species common to the West Atlantic and Gulf of Mexico
Greater spotted dogfish (Greliorhinus starlaris), a species found in the northeastern Atlantic Ocean
Small-spotted catshark (Scyliorhinus canicula), the most common dogfish in the northeastern Atlantic
Sleeper sharks (Somniosidae), a family of slow-swimming sharks
Portuguese dogfish (Centroscymnus coelolepis), a species of sleeper sharks in the family Somniosidae
Roughskin dogfish (Centroscymnus owstonii), a species of sleeper sharks in the family Somniosidae
Bowfin (Amia calva), a freshwater fish sometimes known as "dogfish"
Other uses
Dogfish Bay, an inlet in western Washington, US
Dogfish Pictures, an American film production company
USS Dogfish (SS-350), a U.S. Navy submarine
Iowa Dogfish, a U.S. Senior-A box lacrosse team
See also
Smooth-hound (Mustelus), a genus of sharks
The Terrible Dogfish, a fictional sea monster in Carlo Collodi's 1883 book The Adventures of Pinocchio
Dogfish Head Brewery, an American beer brewery
"Dogfish Rising", a hidden track on Slipknot's 1996 album Mate. Feed. Kill. Repeat.
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https://en.wikipedia.org/wiki/White%20box
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White box may refer to:
White-box testing, a specification conformance test
White box (computer hardware), a personal computer assembled from off-the-shelf parts
White box (software engineering), a subsystem whose internals can be viewed
White-box cryptography, a cryptographic system designed to be secure even when its internals are viewed
Whitebox GAT, an advanced open-source and cross-platform GIS & remote sensing software package
WHITEbox, an album set by Sunn O)))
"White Box", the title of a special Christmas episode in Series 5 of Absolutely Fabulous
White box system, a bilge water monitoring and control system for ships
The "white box" release of the original Dungeons & Dragons rules
White box, Eucalyptus albens, a tree species from Australia
Shirobako (lit. White Box), an anime television series produced by P.A.Works
WhiteBox (art center), an arts center in New York City, United States
See also
Black box (disambiguation)
Grey box (disambiguation)
White cube gallery
White goods
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https://en.wikipedia.org/wiki/TPP
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TPP may refer to:
Science and technology
Chemistry
Tripolyphosphate, a sodium salt of the polyphosphate penta-anion
Thiamine pyrophosphate, an enzyme cofactor
Tetraphenylporphyrin, a synthetic heterocyclic compound that resembles naturally occurring porphyrins
Triphenylphosphine, an organophosphorus compound commonly used in chemical synthesis
Computing and mathematics
Tangential proper part, a relation in region connection calculus
Targeted projection pursuit, a statistical technique for data exploration, feature selection and information visualisation
Transformation Priority Premise, a programming approach that simplifies test-driven development
Traveling purchaser problem, an NP-hard problem generalizing the traveling salesman problem
Trans-Proteomic Pipeline, open-source bioinformatics software
Energy
Thermal power plant is a power station in which heat energy is converted to electric power.
Medicine
Thrombotic thrombocytopenic purpura, a disorder of the blood-coagulation system
Thyrotoxic periodic paralysis, a condition featuring attacks of muscle weakness in the presence of hyperthyroidism
Entertainment
Twitch Plays Pokémon, an interactive video channel
Metal Gear Solid V: The Phantom Pain, a 2015 stealth video game
Third-person perspective, a style of virtual camera system for 3D games
Politics
Trans-Pacific Partnership, a defunct proposed trade agreement between 12 Pacific Rim countries
Comprehensive and Progressive Agreement for Trans-Pacific
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https://en.wikipedia.org/wiki/Pinwheel
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Pinwheel may refer to:
Pinwheel (toy), a spinning children's toy
Pinwheel (cryptography), a device for producing a short pseudo-random sequence of bits
Pinwheel (shogi), an opening in the game shogi or Japanese chess
Pinwheel (TV channel), a channel which would later turn into Nickelodeon
Pinwheel (TV series), a children's show on Nickelodeon that ran from 1977 to 1984
Pinwheel calculator (part of), a type of early mechanical arithmetic machine
Tabernaemontana divaricata, also known as pinwheel flower
Pinwheel tilings, aperiodic tilings of the plane whose tiles appear in infinitely many orientations
Catherine wheel (firework), a form of pyrotechnic display device also known as a pinwheel
Coenocharopa elegans, also known as the elegant pinwheel snail, a land snail found in Queensland, Australia
"Pinwheels", a poem by Patti Smith from her 1978 book Babel
Pinwheel USY, part of United Synagogue Youth covering the Pacific Northwest
Wartenberg wheel, a neurological medical device
See also
Pinwheel Galaxy (disambiguation)
Pinwheel escapement (disambiguation)
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https://en.wikipedia.org/wiki/George%20Zweig
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George Zweig (; born May 30, 1937) is an American physicist of Jewish origin. He was trained as a particle physicist under Richard Feynman. He introduced, independently of Murray Gell-Mann, the quark model (although he named it "aces"). He later turned his attention to neurobiology. He has worked as a research scientist at Los Alamos National Laboratory and Massachusetts Institute of Technology, and in the financial services industry.
Early life
Zweig was born on May 30, 1937 in Moscow, Russian SFSR, Soviet Union, into a Jewish family. His father was a structural engineer. He graduated from the University of Michigan in 1959, with a bachelor's degree in mathematics, having taken numerous physics courses as electives. He earned a PhD degree in theoretical physics at the California Institute of Technology in 1964.
Career
Zweig proposed the existence of quarks at CERN, independently of Murray Gell-Mann, shortly after defending his PhD dissertation. Zweig dubbed them "aces", after the four playing cards, because he speculated there were four of them (on the basis of the four extant leptons known at the time). The introduction of the concept of quarks provided a cornerstone for particle physics.
Like Gell-Mann, he realized that several important properties of particles such as baryons (e.g., protons and neutrons) could be explained by treating them as triplets of other constituent particles, with fractional baryon number and electric charge. Unlike Gell-Mann, Zweig was pa
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https://en.wikipedia.org/wiki/Monounsaturated%20fat
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In biochemistry and nutrition, a monounsaturated fat is a fat that contains a monounsaturated fatty acid (MUFA), a subclass of fatty acid characterized by having a double bond in the fatty acid chain with all of the remaining carbon atoms being single-bonded. By contrast, polyunsaturated fatty acids (PUFAs) have more than one double bond.
Molecular description
Monounsaturated fats are triglycerides containing one unsaturated fatty acid. Almost invariably that fatty acid is oleic acid (18:1 n−9). Palmitoleic acid (16:1 n−7) and cis-vaccenic acid (18:1 n−7) occur in small amounts in fats.
Health
Studies have shown that substituting dietary monounsaturated fat for saturated fat is associated with increased daily physical activity and resting energy expenditure. More physical activity was associated with a higher-oleic acid diet than one of a palmitic acid diet. From the study, it is shown that more monounsaturated fats lead to less anger and irritability.
Foods containing monounsaturated fats may affect low-density lipoprotein (LDL) cholesterol and high-density lipoprotein (HDL) cholesterol.
Levels of oleic acid along with other monounsaturated fatty acids in red blood cell membranes were positively associated with breast cancer risk. The saturation index (SI) of the same membranes was inversely associated with breast cancer risk. Monounsaturated fats and low SI in erythrocyte membranes are predictors of postmenopausal breast cancer. Both of these variables depend on the
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https://en.wikipedia.org/wiki/Wahoo%20%28disambiguation%29
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Wahoo (Acanthocybium solandri) is a scombrid fish found worldwide in tropical and subtropical seas.
Wahoo may also refer to:
Biology
Eastern wahoo (Euonymus atropurpureus), a shrub native to eastern North America, also known as American wahoo or wahoo fruit
Ulmus alata, the winged elm or wahoo, a deciduous tree in the southeastern and south central United States
Geography
Wahoo, California, a former settlement
Wahoo, Nebraska, a city
Wahoo, West Virginia, an unincorporated community in Marion County
Wahoo Township, Saunders County, Nebraska, a township
Wahoo, Florida, a populated area in Florida
Ships
USS Wahoo (SS-238), a Gato-class submarine
USS Wahoo (SS-518), a Tench-class submarine
USS Wahoo (SS-516), a Tench-class submarine
USS Wahoo (SS-565), a Tang-class submarine
Sports
Chief Wahoo, a mascot for the Cleveland Indians baseball team
Wahoos, an unofficial nickname for sports teams of the University of Virginia, officially referred to as the Cavaliers
Wahoo McDaniel (1938–2002), American football player turned professional wrestler
Pensacola Blue Wahoos, minor league baseball team located in Pensacola, FL
Other uses
Wahoo!, a 1965 album by American pianist and arranger Duke Pearson
Wahoo (board game), a board game
Wahoo! (company), a United States-based corporation which built fiberglass recreational boats from 1985 to 1996
Wahoo (underwater nuclear test), conducted as part of Operation Hardtack I
Wahoo Fitness, a manufacturer of cycling an
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https://en.wikipedia.org/wiki/Bernard%20Chazelle
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Bernard Chazelle (born November 5, 1955) is a French-born computer scientist. He is currently the Eugene Higgins Professor of Computer Science at Princeton University. Much of his work is in computational geometry, where he is known for his study of algorithms, such as linear-time triangulation of a simple polygon, as well as major complexity results, such as lower bound techniques based on discrepancy theory. He is also known for his invention of the soft heap data structure and the most asymptotically efficient known deterministic algorithm for finding minimum spanning trees.
Early life
Chazelle was born in Clamart, France, the son of Marie-Claire (née Blanc) and Jean Chazelle. He grew up in Paris, France, where he received his bachelor's degree and master's degree in applied mathematics at the École des mines de Paris in 1977. Then, at the age of 21, he attended Yale University in the United States, where he received his PhD in computer science in 1980 under the supervision of David P. Dobkin.
Career
Chazelle accepted professional appointments at institutions such as Brown, NEC, Xerox PARC, the Institute for Advanced Study, and the Paris institutions École normale supérieure, École polytechnique, Inria, and Collège de France. He is a fellow of the ACM, the American Academy of Arts and Sciences, the John Simon Guggenheim Memorial Foundation, and NEC, as well as a member of the European Academy of Sciences. He has also written essays about music and politics.
Personal li
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https://en.wikipedia.org/wiki/Pincer
|
Pincer may refer to:
Pincers (tool)
Pincer (biology), part of an animal
Pincer ligand, a terdentate, often planar molecule that tightly binds a variety of metal ions
The Pincer move in the game of Go
See also
Pincer movement, military manoeuvre
Pincer nail (medicine)
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https://en.wikipedia.org/wiki/Fusion%20tree
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In computer science, a fusion tree is a type of tree data structure that implements an associative array on -bit integers on a finite universe, where each of the input integers has size less than 2w and is non-negative. When operating on a collection of key–value pairs, it uses space and performs searches in time, which is asymptotically faster than a traditional self-balancing binary search tree, and also better than the van Emde Boas tree for large values of . It achieves this speed by using certain constant-time operations that can be done on a machine word. Fusion trees were invented in 1990 by Michael Fredman and Dan Willard.
Several advances have been made since Fredman and Willard's original 1990 paper. In 1999 it was shown how to implement fusion trees under a model of computation in which all of the underlying operations of the algorithm belong to AC0, a model of circuit complexity that allows addition and bitwise Boolean operations but does not allow the multiplication operations used in the original fusion tree algorithm. A dynamic version of fusion trees using hash tables was proposed in 1996 which matched the original structure's runtime in expectation. Another dynamic version using exponential tree was proposed in 2007 which yields worst-case runtimes of per operation. Finally, it was shown that dynamic fusion trees can perform each operation in time deterministically.
This data structure implements add key, remove key, search key, and predecessor (next
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https://en.wikipedia.org/wiki/Clive%20Matthewson
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Clive Denby Matthewson (born 1944) is a New Zealand civil engineer and former politician.
Biography
Early life and career
Matthewson was born in Wellington in 1944. He was educated at Waitaki Boys' High School and University of Canterbury. He has a PhD in Civil Engineering which he completed in 1970. The title of his PhD thesis was: "The elastic behaviour of a laterally loaded pile". He worked as a civil engineer until he was elected to parliament in 1984.
Political career
He was chairman of the electorate for the Labour Party and also a member of Labour's governing body the New Zealand Council. In 1977, he sought the Labour nomination for the Christchurch electorate of , but was beaten by former MP Mike Moore. Two years later he stood for the Labour candidacy for the seat in a by-election, but was again unsuccessful. Matthewson then unsuccessfully contested the electorate in the for the Labour Party.
In the 1983 electoral redistribution, the number of Dunedin electorates was reduced from three to two. Brian MacDonell, who had since represented , was supposed to represent the new Dunedin West electorate. However, Labour's president, Jim Anderton, presided over MacDonell's de-selection and installed his personal friend Matthewson instead. Matthewson was elected to Dunedin West in . Matthewson was considered one of the most effective backbenchers in the Fourth Labour Government. In August 1989, he was appointed by Prime Minister Geoffrey Palmer as Under-Secretary to
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https://en.wikipedia.org/wiki/Euler%20system
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In mathematics, an Euler system is a collection of compatible elements of Galois cohomology groups indexed by fields. They were introduced by in his work on Heegner points on modular elliptic curves, which was motivated by his earlier paper and the work of . Euler systems are named after Leonhard Euler because the factors relating different elements of an Euler system resemble the Euler factors of an Euler product.
Euler systems can be used to construct annihilators of ideal class groups or Selmer groups, thus giving bounds on their orders, which in turn has led to deep theorems such as the finiteness of some Tate-Shafarevich groups. This led to Karl Rubin's new proof of the main conjecture of Iwasawa theory, considered simpler than the original proof due to Barry Mazur and Andrew Wiles.
Definition
Although there are several definitions of special sorts of Euler system, there seems to be no published definition of an Euler system that covers all known cases. But it is possible to say roughly what an Euler system is, as follows:
An Euler system is given by collection of elements cF. These elements are often indexed by certain number fields F containing some fixed number field K, or by something closely related such as square-free integers. The elements cF are typically elements of some Galois cohomology group such as H1(F, T) where T is a p-adic representation of the absolute Galois group of K.
The most important condition is that the elements cF and cG for two diff
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https://en.wikipedia.org/wiki/Gottlieb%20Conrad%20Christian%20Storr
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Gottlieb Conrad Christian Storr (June 16, 1749, Stuttgart – February 27, 1821, Tübingen) was a German physician, chemist, and naturalist.
In 1768 he obtained his doctorate from the University of Tübingen, where he also served as a professor of chemistry, botany, and natural history from 1774 to 1801. He is the taxonomic authority of several genera, including Mellivora, whose only species is the honey badger (Mellivora capensis).
Published works
In 1781 he performed extensive scientific investigations in the Swiss Alps, publishing "" (1784–86, 2 vols.) as a result. Other noted written efforts by Storr include:
"", 1768 (with Ferdinand Christoph Oetinger).
, 1777.
, 1780.
"", 1785.
"Idea methodi fossilium", 1807.
References
German naturalists
1749 births
1821 deaths
18th-century German physicians
University of Tübingen alumni
Academic staff of the University of Tübingen
Scientists from Stuttgart
Physicians from Stuttgart
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https://en.wikipedia.org/wiki/Statistical%20learning%20theory
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Statistical learning theory is a framework for machine learning drawing from the fields of statistics and functional analysis. Statistical learning theory deals with the statistical inference problem of finding a predictive function based on data. Statistical learning theory has led to successful applications in fields such as computer vision, speech recognition, and bioinformatics.
Introduction
The goals of learning are understanding and prediction. Learning falls into many categories, including supervised learning, unsupervised learning, online learning, and reinforcement learning. From the perspective of statistical learning theory, supervised learning is best understood. Supervised learning involves learning from a training set of data. Every point in the training is an input–output pair, where the input maps to an output. The learning problem consists of inferring the function that maps between the input and the output, such that the learned function can be used to predict the output from future input.
Depending on the type of output, supervised learning problems are either problems of regression or problems of classification. If the output takes a continuous range of values, it is a regression problem. Using Ohm's law as an example, a regression could be performed with voltage as input and current as an output. The regression would find the functional relationship between voltage and current to be , such that
Classification problems are those for which the output wil
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https://en.wikipedia.org/wiki/G%26T
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G&T can mean:
Gin and tonic
Geometry & Topology — a peer-refereed, international mathematics research journal.
Geometry and trigonometry
the Gifted And Talented
a Gifted And Talented program
Generation & Transmission cooperative (wholesale energy provider)
Gramophone & Typewriter Ltd
G&T Crampton, an Irish construction company
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https://en.wikipedia.org/wiki/Transversion
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Transversion, in molecular biology, refers to a point mutation in DNA in which a single (two ring) purine (A or G) is changed for a (one ring) pyrimidine (T or C), or vice versa. A transversion can be spontaneous, or it can be caused by ionizing radiation or alkylating agents. It can only be reversed by a spontaneous reversion.
Ratio of transitions to transversions
Although there are two possible transversions but only one possible transition per base, transition mutations are more likely than transversions because substituting a single ring structure for another single ring structure is more likely than substituting a double ring for a single ring. Also, transitions are less likely to result in amino acid substitutions (due to wobble base pair), and are therefore more likely to persist as "silent substitutions" in populations as single nucleotide polymorphisms (SNPs). A transversion usually has a more pronounced effect than a transition because the third nucleotide codon position of the DNA, which to a large extent is responsible for the degeneracy of the code, is more tolerant of transition than a transversion: that is, a transition is more likely to encode for the same amino acid.
Spontaneous germline transversion
8-oxo-2'-deoxyguanosine (8-oxodG) is an oxidized derivative of deoxyguanosine, and is one of the major products of DNA oxidation. During DNA replication in the germ line of mice, the oxidized base 8-oxoguanine (8-oxoG) causes spontaneous and heritable G to T
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https://en.wikipedia.org/wiki/Functional%20genomics
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Functional genomics is a field of molecular biology that attempts to describe gene (and protein) functions and interactions. Functional genomics make use of the vast data generated by genomic and transcriptomic projects (such as genome sequencing projects and RNA sequencing). Functional genomics focuses on the dynamic aspects such as gene transcription, translation, regulation of gene expression and protein–protein interactions, as opposed to the static aspects of the genomic information such as DNA sequence or structures. A key characteristic of functional genomics studies is their genome-wide approach to these questions, generally involving high-throughput methods rather than a more traditional "candidate-gene" approach.
Definition and goals of functional genomics
In order to understand functional genomics it is important to first define function. In their paper Graur et al. define function in two possible ways. These are "selected effect" and "causal role". The "selected effect" function refers to the function for which a trait (DNA, RNA, protein etc.) is selected for. The "causal role" function refers to the function that a trait is sufficient and necessary for. Functional genomics usually tests the "causal role" definition of function.
The goal of functional genomics is to understand the function of genes or proteins, eventually all components of a genome. The term functional genomics is often used to refer to the many technical approaches to study an organism's gene
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https://en.wikipedia.org/wiki/Stein%20manifold
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In mathematics, in the theory of several complex variables and complex manifolds, a Stein manifold is a complex submanifold of the vector space of n complex dimensions. They were introduced by and named after . A Stein space is similar to a Stein manifold but is allowed to have singularities. Stein spaces are the analogues of affine varieties or affine schemes in algebraic geometry.
Definition
Suppose is a complex manifold of complex dimension and let denote the ring of holomorphic functions on We call a Stein manifold if the following conditions hold:
is holomorphically convex, i.e. for every compact subset , the so-called holomorphically convex hull,
is also a compact subset of .
is holomorphically separable, i.e. if are two points in , then there exists such that
Non-compact Riemann surfaces are Stein manifolds
Let X be a connected, non-compact Riemann surface. A deep theorem of Heinrich Behnke and Stein (1948) asserts that X is a Stein manifold.
Another result, attributed to Hans Grauert and Helmut Röhrl (1956), states moreover that every holomorphic vector bundle on X is trivial. In particular, every line bundle is trivial, so . The exponential sheaf sequence leads to the following exact sequence:
Now Cartan's theorem B shows that , therefore .
This is related to the solution of the second Cousin problem.
Properties and examples of Stein manifolds
The standard complex space is a Stein manifold.
Every domain of holomorphy in is a Stein manif
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https://en.wikipedia.org/wiki/Stevens%27s%20power%20law
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Stevens' power law is an empirical relationship in psychophysics between an increased intensity or strength in a physical stimulus and the perceived magnitude increase in the sensation created by the stimulus. It is often considered to supersede the Weber–Fechner law, which is based on a logarithmic relationship between stimulus and sensation, because the power law describes a wider range of sensory comparisons, down to zero intensity.
The theory is named after psychophysicist Stanley Smith Stevens (1906–1973). Although the idea of a power law had been suggested by 19th-century researchers, Stevens is credited with reviving the law and publishing a body of psychophysical data to support it in 1957.
The general form of the law is
where I is the intensity or strength of the stimulus in physical units (energy, weight, pressure, mixture proportions, etc.), ψ(I) is the magnitude of the sensation evoked by the stimulus, a is an exponent that depends on the type of stimulation or sensory modality, and k is a proportionality constant that depends on the units used.
A distinction has been made between local psychophysics, where stimuli can only be discriminated with a probability around 50%, and global psychophysics, where the stimuli can be discriminated correctly with near certainty (Luce & Krumhansl, 1988). The Weber–Fechner law and methods described by L. L. Thurstone are generally applied in local psychophysics, whereas Stevens' methods are usually applied in global psychoph
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https://en.wikipedia.org/wiki/INV
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INV may refer to:
Inverter (logic gate)
Inverness Airport, IATA airport code
Inverness railway station, Scotland; National Rail station code INV
Inverness-shire, county in Scotland, Chapman code
Irish National Volunteers
Inverse (mathematics)
Invected (Drosophila melanogaster gene)
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https://en.wikipedia.org/wiki/ACD
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ACD may refer to:
Brands and enterprises
ACD (telecommunications company), carrier and Internet Service Provider, headquartered in Lansing, Michigan
ACD Systems, a computer software manufacturer
Advanced Chemistry Development (ACD/Labs), a chemistry software company
Organizations
ACD San Marcial, a Spanish football team based in Lardero, La Rioja
Adelaide College of Divinity, an Australian theological college
Arbeitsgemeinschaft der Christengemeinden in Deutschland (Association of Christian Churches in Germany)
Asia Cooperation Dialogue, an international organization
Centre Right Alliance (Romania) (), a political alliance
Australasian College of Dermatologists, a medical specialist college
People
Arthur Conan Doyle, creator of Sherlock Holmes
Science and healthcare
ACD (gene), protein encoded by the ACD gene
α-Cyclodextrin, a glucose polymer
Alveolar capillary dysplasia, disorder of the lung
Anemia of chronic disease, form of anemia
Aragonite compensation depth, a property of oceans
Allergic contact dermatitis, form of contact dermatitis
Technology
Activity-centered design, design based on how humans interact with technology
Anti-collision device, on Indian railways
Apple Cinema Display, a line of monitors
Automatic call distributor, device that directs incoming phone calls
Average call duration, average length of telephone calls
Other uses
ACD (album), a 1989 album by Half Man Half Biscuit
Adjournment in contemplation of dismissal, court ruling t
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https://en.wikipedia.org/wiki/Grade%20separation
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In civil engineering (more specifically highway engineering), grade separation is a method of aligning a junction of two or more surface transport axes at different heights (grades) so that they will not disrupt the traffic flow on other transit routes when they cross each other. The composition of such transport axes does not have to be uniform; it can consist of a mixture of roads, footpaths, railways, canals, or airport runways. Bridges (or overpasses, also called flyovers), tunnels (or underpasses), or a combination of both can be built at a junction to achieve the needed grade separation.
In North America, a grade-separated junction may be referred to as a grade separation or as an interchange – in contrast with an intersection, at-grade, a diamond crossing or a level crossing, which are not grade-separated.
Effects
Advantages
Roads with grade separation generally allow traffic to move freely, with fewer interruptions, and at higher overall speeds; this is why speed limits are typically higher for grade-separated roads. In addition, reducing the complexity of traffic movements reduces the risk of accidents.
Disadvantages
Grade-separated road junctions are typically space-intensive, complicated, and costly, due to the need for large physical structures such as tunnels, ramps, and bridges. Their height can be obtrusive, and this, combined with the large traffic volumes that grade-separated roads attract, tend to make them unpopular to nearby landowners and residents.
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https://en.wikipedia.org/wiki/Llu%C3%ADs%20Dom%C3%A8nech%20i%20Montaner
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Lluís Domènech i Montaner (; 21 December 1850 – 27 December 1923) was a Catalan architect who was very much involved in and influential for the Catalan Modernisme català, the Art Nouveau/Jugendstil movement. He was also a Catalan politician.
Born in Barcelona, he initially studied physics and natural sciences, but soon switched to architecture. He was registered as an architect in Barcelona in 1873. He also held a 45-year tenure as a professor and director at the Escola d'Arquitectura, Barcelona's school of architecture, and wrote extensively on architecture in essays, technical books and articles in newspapers and journals.
His most famous buildings, the Hospital de Sant Pau and Palau de la Música Catalana in Barcelona, have been collectively designated as a UNESCO World Heritage Site.
As an architect, 45-year professor of architecture and prolific writer on architecture, Domènech i Montaner played an important role in defining the Modernisme arquitectonic in Catalonia. This style has become internationally renowned, mainly due to the work of Antoni Gaudí. Domènech i Montaner's article "En busca d'una arquitectura nacional" (In search of a national architecture), published 1878 in the journal La Renaixença, reflected the way architects at that time sought to build structures that reflected the Catalan character.
His buildings displayed a mixture between rationalism and fabulous ornamentation inspired by Spanish-Arabic architecture, and followed the curvilinear design ty
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https://en.wikipedia.org/wiki/Sheaf%20cohomology
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In mathematics, sheaf cohomology is the application of homological algebra to analyze the global sections of a sheaf on a topological space. Broadly speaking, sheaf cohomology describes the obstructions to solving a geometric problem globally when it can be solved locally. The central work for the study of sheaf cohomology is Grothendieck's 1957 Tôhoku paper.
Sheaves, sheaf cohomology, and spectral sequences were introduced by Jean Leray at the prisoner-of-war camp Oflag XVII-A in Austria. From 1940 to 1945, Leray and other prisoners organized a "université en captivité" in the camp.
Leray's definitions were simplified and clarified in the 1950s. It became clear that sheaf cohomology was not only a new approach to cohomology in algebraic topology, but also a powerful method in complex analytic geometry and algebraic geometry. These subjects often involve constructing global functions with specified local properties, and sheaf cohomology is ideally suited to such problems. Many earlier results such as the Riemann–Roch theorem and the Hodge theorem have been generalized or understood better using sheaf cohomology.
Definition
The category of sheaves of abelian groups on a topological space X is an abelian category, and so it makes sense to ask when a morphism f: B → C of sheaves is injective (a monomorphism) or surjective (an epimorphism). One answer is that f is injective (respectively surjective) if and only if the associated homomorphism on stalks Bx → Cx is injective (re
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https://en.wikipedia.org/wiki/Japanese%20mathematics
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denotes a distinct kind of mathematics which was developed in Japan during the Edo period (1603–1867). The term wasan, from wa ("Japanese") and san ("calculation"), was coined in the 1870s and employed to distinguish native Japanese mathematical theory from Western mathematics (洋算 yōsan).
In the history of mathematics, the development of wasan falls outside the Western realm. At the beginning of the Meiji period (1868–1912), Japan and its people opened themselves to the West. Japanese scholars adopted Western mathematical technique, and this led to a decline of interest in the ideas used in wasan.
History
The Japanese mathematical schema evolved during a period when Japan's people were isolated from European influences, but instead borrowed from ancient mathematical texts written in China, including those from the Yuan dynasty and earlier. The Japanese mathematicians Yoshida Shichibei Kōyū, Imamura Chishō, and Takahara Kisshu are among the earliest known Japanese mathematicians. They came to be known to their contemporaries as "the Three Arithmeticians".
Yoshida was the author of the oldest extant Japanese mathematical text, the 1627 work called Jinkōki. The work dealt with the subject of soroban arithmetic, including square and cube root operations. Yoshida's book significantly inspired a new generation of mathematicians, and redefined the Japanese perception of educational enlightenment, which was defined in the Seventeen Article Constitution as "the product of earnes
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https://en.wikipedia.org/wiki/Deniable%20encryption
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In cryptography and steganography, plausibly deniable encryption describes encryption techniques where the existence of an encrypted file or message is deniable in the sense that an adversary cannot prove that the plaintext data exists.
The users may convincingly deny that a given piece of data is encrypted, or that they are able to decrypt a given piece of encrypted data, or that some specific encrypted data exists. Such denials may or may not be genuine. For example, it may be impossible to prove that the data is encrypted without the cooperation of the users. If the data is encrypted, the users genuinely may not be able to decrypt it. Deniable encryption serves to undermine an attacker's confidence either that data is encrypted, or that the person in possession of it can decrypt it and provide the associated plaintext.
Function
Deniable encryption makes it impossible to prove the existence of the plaintext message without the proper decryption key. This may be done by allowing an encrypted message to be decrypted to different sensible plaintexts, depending on the key used. This allows the sender to have plausible deniability if compelled to give up their encryption key.
The notion of "deniable encryption" was used by Julian Assange and Ralf Weinmann in the Rubberhose filesystem and explored in detail in a paper by Ran Canetti, Cynthia Dwork, Moni Naor, and Rafail Ostrovsky in 1996.
Scenario
Deniable encryption allows the sender of an encrypted message to deny sending th
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https://en.wikipedia.org/wiki/Hao%20Wang%20%28academic%29
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Hao Wang (; 20 May 1921 – 13 May 1995) was a Chinese-American logician, philosopher, mathematician, and commentator on Kurt Gödel.
Biography
Born in Jinan, Shandong, in the Republic of China (today in the People's Republic of China), Wang received his early education in China. He obtained a BSc degree in mathematics from the National Southwestern Associated University in 1943 and an M.A. in Philosophy from Tsinghua University in 1945, where his teachers included Feng Youlan and Jin Yuelin, after which he moved to the United States for further graduate studies. He studied logic under W.V. Quine at Harvard University, culminating in a Ph.D. in 1948. He was appointed to an assistant professorship at Harvard the same year.
During the early 1950s, Wang studied with Paul Bernays in Zürich. In 1956, he was appointed Reader in the Philosophy of Mathematics at the University of Oxford. In 1959, Wang wrote on an IBM 704 computer a program that in only 9 minutes mechanically proved several hundred mathematical logic theorems in Whitehead and Russell's Principia Mathematica. In 1961, he was appointed Gordon McKay Professor of Mathematical Logic and Applied Mathematics at Harvard. From 1967 until 1991, he headed the logic research group at Rockefeller University in New York City, where he was professor of logic. In 1972, Wang joined in a group of Chinese American scientists led by Chih-Kung Jen as the first such delegation from the U.S. to the People's Republic of China.
One of Wang's
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https://en.wikipedia.org/wiki/Yeshayahu%20Leibowitz
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Yeshayahu Leibowitz (; 29 January 1903 – 18 August 1994) was an Israeli Orthodox Jewish public intellectual and polymath. He was a professor of biochemistry, organic chemistry, and neurophysiology at the Hebrew University of Jerusalem, as well as a prolific writer on Jewish thought and western philosophy. He was known for his outspoken views on ethics, religion, and politics. Leibowitz cautioned that the state of Israel and Zionism had become more sacred than Jewish humanist values and controversially went on to describe Israeli conduct in the occupied Palestinian territories as "Judeo-Nazi" in nature while warning of the dehumanizing effect of the occupation on the victims and the oppressors.
Biography
Yeshayahu Leibowitz was born in Riga, Russian Empire (now in Latvia) in 1903, to a religious Zionist family. His father was a lumber trader, and his cousin was a future chess grandmaster Aron Nimzowitsch. In 1919, he studied chemistry and philosophy at the University of Berlin. After completing his doctorate in 1924, he went on to study biochemistry and medicine, receiving an MD in 1934 from the University of Basel.
He immigrated to Mandate Palestine in 1935, and settled in Jerusalem. Leibowitz was married to Greta, with whom he had six children, two of whom died at young ages. His son Elia was chairman of the Tel Aviv University astrophysics department, and the longest-serving director of the Wise Observatory. Another son, Uri, was a professor of medicine at Hadassah Univer
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https://en.wikipedia.org/wiki/GC-content
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In molecular biology and genetics, GC-content (or guanine-cytosine content) is the percentage of nitrogenous bases in a DNA or RNA molecule that are either guanine (G) or cytosine (C). This measure indicates the proportion of G and C bases out of an implied four total bases, also including adenine and thymine in DNA and adenine and uracil in RNA.
GC-content may be given for a certain fragment of DNA or RNA or for an entire genome. When it refers to a fragment, it may denote the GC-content of an individual gene or section of a gene (domain), a group of genes or gene clusters, a non-coding region, or a synthetic oligonucleotide such as a primer.
Structure
Qualitatively, guanine (G) and cytosine (C) undergo a specific hydrogen bonding with each other, whereas adenine (A) bonds specifically with thymine (T) in DNA and with uracil (U) in RNA. Quantitatively, each GC base pair is held together by three hydrogen bonds, while AT and AU base pairs are held together by two hydrogen bonds. To emphasize this difference, the base pairings are often represented as "G≡C" versus "A=T" or "A=U".
DNA with low GC-content is less stable than DNA with high GC-content; however, the hydrogen bonds themselves do not have a particularly significant impact on molecular stability, which is instead caused mainly by molecular interactions of base stacking. In spite of the higher thermostability conferred to a nucleic acid with high GC-content, it has been observed that at least some species of bacteri
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https://en.wikipedia.org/wiki/Microbial%20ecology
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Microbial ecology (or environmental microbiology) is the ecology of microorganisms: their relationship with one another and with their environment. It concerns the three major domains of life—Eukaryota, Archaea, and Bacteria—as well as viruses.
Microorganisms, by their omnipresence, impact the entire biosphere. Microbial life plays a primary role in regulating biogeochemical systems in virtually all of our planet's environments, including some of the most extreme, from frozen environments and acidic lakes, to hydrothermal vents at the bottom of deepest oceans, and some of the most familiar, such as the human small intestine, nose, and mouth. As a consequence of the quantitative magnitude of microbial life (calculated as cells; eight orders of magnitude greater than the number of stars in the observable universe) microbes, by virtue of their biomass alone, constitute a significant carbon sink. Aside from carbon fixation, microorganisms' key collective metabolic processes (including nitrogen fixation, methane metabolism, and sulfur metabolism) control global biogeochemical cycling. The immensity of microorganisms' production is such that, even in the total absence of eukaryotic life, these processes would likely continue unchanged.
History
While microbes have been studied since the seventeenth-century, this research was from a primarily physiological perspective rather than an ecological one. For instance, Louis Pasteur and his disciples were interested in the problem of
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https://en.wikipedia.org/wiki/L%C3%A9vy%20C%20curve
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In mathematics, the Lévy C curve is a self-similar fractal curve that was first described and whose differentiability properties were analysed by Ernesto Cesàro in 1906 and Georg Faber in 1910, but now bears the name of French mathematician Paul Lévy, who was the first to describe its self-similarity properties as well as to provide a geometrical construction showing it as a representative curve in the same class as the Koch curve. It is a special case of a period-doubling curve, a de Rham curve.
L-system construction
If using a Lindenmayer system then the construction of the C curve starts with a straight line. An isosceles triangle with angles of 45°, 90° and 45° is built using this line as its hypotenuse. The original line is then replaced by the other two sides of this triangle.
At the second stage, the two new lines each form the base for another right-angled isosceles triangle, and are replaced by the other two sides of their respective triangle. So, after two stages, the curve takes the appearance of three sides of a rectangle with the same length as the original line, but only half as wide.
At each subsequent stage, each straight line segment in the curve is replaced by the other two sides of a right-angled isosceles triangle built on it. After n stages the curve consists of 2n line segments, each of which is smaller than the original line by a factor of 2n/2.
This L-system can be described as follows:
where "" means "draw forward", "+" means "turn clockwise 45°
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https://en.wikipedia.org/wiki/James%20Rumbaugh
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James E. Rumbaugh (born August 22, 1947) is an American computer scientist and object-oriented methodologist who is best known for his work in creating the Object Modeling Technique (OMT) and the Unified Modeling Language (UML).
Biography
Born in Bethlehem, Pennsylvania, Rumbaugh received a B.S. in physics from the Massachusetts Institute of Technology (MIT), an M.S. in astronomy from the California Institute of Technology (Caltech), and received a Ph.D. in computer science from MIT under Professor Jack Dennis.
Rumbaugh started his career in the 1960s at Digital Equipment Corporation (DEC) as a lead research scientist. From 1968 to 1994 he worked at the General Electric Research and Development Center developing technology, teaching, and consulting. At General Electric he also led the development of Object-modeling technique (OMT), an object modeling language for software modeling and designing.
In 1994, he joined Rational Software, where he worked with Ivar Jacobson and Grady Booch ("the Three Amigos") to develop Unified Modeling Language (UML). Later they merged their software development methologies, OMT, OOSE and Booch into the Rational Unified Process (RUP). In 2003 he moved to IBM, after its acquisition of Rational Software. He retired in 2006.
He has two grown up children and (in 2009) lived in Saratoga, California with his wife.
Work
Rumbaugh's main research interests are formal description languages, "semantics of computation, tools for programming productivit
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https://en.wikipedia.org/wiki/Quantum%20field%20theory%20in%20curved%20spacetime
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In theoretical physics, quantum field theory in curved spacetime (QFTCS) is an extension of quantum field theory from Minkowski spacetime to a general curved spacetime. This theory uses a semi-classical approach; it treats spacetime as a fixed, classical background, while giving a quantum-mechanical description of the matter and energy propagating through that spacetime. A general prediction of this theory is that particles can be created by time-dependent gravitational fields (multigraviton pair production), or by time-independent gravitational fields that contain horizons. The most famous example of the latter is the phenomenon of Hawking radiation emitted by black holes.
Overview
Ordinary quantum field theories, which form the basis of standard model, are defined in flat Minkowski space, which is an excellent approximation when it comes to describing the behavior of microscopic particles in weak gravitational fields like those found on Earth. In order to describe situations in which gravity is strong enough to influence (quantum) matter, yet not strong enough to require quantization itself, physicists have formulated quantum field theories in curved spacetime. These theories rely on general relativity to describe a curved background spacetime, and define a generalized quantum field theory to describe the behavior of quantum matter within that spacetime.
For non-zero cosmological constants, on curved spacetimes quantum fields lose their interpretation as asymptotic parti
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https://en.wikipedia.org/wiki/Human%20behaviour%20genetics
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Human behaviour genetics is an interdisciplinary subfield of behaviour genetics that studies the role of genetic and environmental influences on human behaviour. Classically, human behavioural geneticists have studied the inheritance of behavioural traits. The field was originally focused on determining the importance of genetic influences on human behaviour (for e.g., do genes regulate human behavioural attributes). It has evolved to address more complex questions such as: how important are genetic and/or environmental influences on various human behavioural traits; to what extent do the same genetic and/or environmental influences impact the overlap between human behavioural traits; how do genetic and/or environmental influences on behaviour change across development; and what environmental factors moderate the importance of genetic effects on human behaviour (gene-environment interaction). The field is interdisciplinary, and draws from genetics, psychology, and statistics. Most recently, the field has moved into the area of statistical genetics, with many behavioural geneticists also involved in efforts to identify the specific genes involved in human behaviour, and to understand how the effects associated with these genes changes across time, and in conjunction with the environment.
Traditionally, the human behavioural genetics were a psychology and phenotype based studies including intelligence, personality and grasping ability. During the years, the study developed bey
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https://en.wikipedia.org/wiki/Super-Poincar%C3%A9%20algebra
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In theoretical physics, a super-Poincaré algebra is an extension of the Poincaré algebra to incorporate supersymmetry, a relation between bosons and fermions. They are examples of supersymmetry algebras (without central charges or internal symmetries), and are Lie superalgebras. Thus a super-Poincaré algebra is a Z2-graded vector space with a graded Lie bracket such that the even part is a Lie algebra containing the Poincaré algebra, and the odd part is built from spinors on which there is an anticommutation relation with values in the even part.
Informal sketch
The Poincaré algebra describes the isometries of Minkowski spacetime. From the representation theory of the Lorentz group, it is known that the Lorentz group admits two inequivalent complex spinor representations, dubbed and . Taking their tensor product, one obtains ; such decompositions of tensor products of representations into direct sums is given by the Littlewood–Richardson rule.
Normally, one treats such a decomposition as relating to specific particles: so, for example, the pion, which is a chiral vector particle, is composed of a quark-anti-quark pair. However, one could also identify with Minkowski spacetime itself. This leads to a natural question: if Minkowski space-time belongs to the adjoint representation, then can Poincaré symmetry be extended to the fundamental representation? Well, it can: this is exactly the super-Poincaré algebra. There is a corresponding experimental question: if we live in th
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https://en.wikipedia.org/wiki/Semigroup%20action
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In algebra and theoretical computer science, an action or act of a semigroup on a set is a rule which associates to each element of the semigroup a transformation of the set in such a way that the product of two elements of the semigroup (using the semigroup operation) is associated with the composite of the two corresponding transformations. The terminology conveys the idea that the elements of the semigroup are acting as transformations of the set. From an algebraic perspective, a semigroup action is a generalization of the notion of a group action in group theory. From the computer science point of view, semigroup actions are closely related to automata: the set models the state of the automaton and the action models transformations of that state in response to inputs.
An important special case is a monoid action or act, in which the semigroup is a monoid and the identity element of the monoid acts as the identity transformation of a set. From a category theoretic point of view, a monoid is a category with one object, and an act is a functor from that category to the category of sets. This immediately provides a generalization to monoid acts on objects in categories other than the category of sets.
Another important special case is a transformation semigroup. This is a semigroup of transformations of a set, and hence it has a tautological action on that set. This concept is linked to the more general notion of a semigroup by an analogue of Cayley's theorem.
(A note on t
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https://en.wikipedia.org/wiki/Supportability
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Supportability may refer to:
Supportability (engineering)
Supportability (computer science)
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https://en.wikipedia.org/wiki/Frederick%20Dainton%2C%20Baron%20Dainton
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Frederick Sydney Dainton, Baron Dainton, Kt, FRS, FRSE (11 November 1914 – 5 December 1997) was a British academic chemist and university administrator.
A graduate of Oxford and Cambridge, he was successively Professor of Physical Chemistry at the University of Leeds, Vice-Chancellor of the University of Nottingham, Dr Lee's Professor of Chemistry at Oxford and Chancellor of the University of Sheffield.
Early life and education
Dainton was born in Sheffield on 11 November 1914, the son of George Whalley Dainton (born 1857), a Clerk of Works to a building contractor, and his second wife Mary Jane Bottrill, as the youngest of nine children.
He obtained a scholarship to the Central Secondary School in Sheffield, but it was in the public library that he became enthused of chemistry by reading the books of Sidgwick and Hinshelwood.
Dainton won an Exhibition at St John's College, Oxford with a supplementary grant and loan from the City of Sheffield, which enabled him to study chemistry, gaining a first class degree in 1937. He then moved to Sidney Sussex College, Cambridge where he received his PhD in 1940 working on photochemistry under Ronald Norrish, FRS.
Academic career
Being short-sighted Dainton was unfit for military service and stayed to teach at Cambridge during the Second World War. In 1945 he became a Fellow of St Catharine's College, Cambridge.
In polymer chemistry he explained the thermodynamics of the ceiling temperature of depolymerizable polymers in 1948.
In
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https://en.wikipedia.org/wiki/Epimer
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In stereochemistry, an epimer is one of a pair of diastereomers. The two epimers have opposite configuration at only one stereogenic center out of at least two. All other stereogenic centers in the molecules are the same in each. Epimerization is the interconversion of one epimer to the other epimer.
Doxorubicin and epirubicin are two epimers that are used as drugs.
Examples
The stereoisomers β-D-glucopyranose and β-D-mannopyranose are epimers because they differ only in the stereochemistry at the C-2 position. The hydroxy group in β-D-glucopyranose is equatorial (in the "plane" of the ring), while in β-D-mannopyranose the C-2 hydroxy group is axial (up from the "plane" of the ring). These two molecules are epimers but, because they are not mirror images of each other, are not enantiomers. (Enantiomers have the same name, but differ in D and L classification.) They are also not sugar anomers, since it is not the anomeric carbon involved in the stereochemistry. Similarly, β-D-glucopyranose and β-D-galactopyranose are epimers that differ at the C-4 position, with the former being equatorial and the latter being axial.
In the case that the difference is the -OH groups on C-1, the anomeric carbon, such as in the case of α-D-glucopyranose and β-D-glucopyranose, the molecules are both epimers and anomers (as indicated by the α and β designation).
Other closely related compounds are epi-inositol and inositol and lipoxin and epilipoxin.
Epimerization
Epimerization is a chemical
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https://en.wikipedia.org/wiki/W%C5%82adys%C5%82aw%20Dziewulski
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Władysław Dziewulski (2 September 1878 – 6 February 1962) was a Polish astronomer and mathematician. He spent most his life performing astronomical research, and published over 200 papers.
Life
He studied mathematics and astronomy in his native Warsaw. Then in 1902 he went to the University of Göttingen in Germany to complete his education. In 1903, he was named as an assistant at the astronomical observatory in Kraków that belonged to the Jagiellonian University and in 1906, he gained his PhD there. In 1919, he became a professor of the Batory University in Vilna and director of its Astronomical Observatory. He was also the rector of Batory University in 1924–25. Later he moved to Nicolaus Copernicus University in Toruń. He spent the last part of his life in Toruń.
He focused on the gravitational perturbations of minor planets, movements of stellar groupings, and photographic photometry.
The crater Dziewulski on the Moon is named after him, as is the Wladyslaw Dziewulski Planetarium in Toruń.
References
20th-century Polish astronomers
Scientists from Warsaw
University of Göttingen alumni
Academic staff of Jagiellonian University
Academic staff of Nicolaus Copernicus University in Toruń
Rectors of Vilnius University
1878 births
1962 deaths
19th-century Polish astronomers
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https://en.wikipedia.org/wiki/Alice%20mobile%20robot
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The Alice is a very small "sugarcube" mobile robot (2x2x2cm) developed at the Autonomous Systems Lab (ASL) at the École Polytechnique Fédérale de Lausanne in Lausanne, Switzerland between 1998 and 2004. It has been part of the Institute of Robotics and Intelligent Systems (IRIS) at Swiss Federal Institute of Technology in Zürich (ETH Zurich) since 2006.
It was designed with the following goals:
Design an intelligent mobile robot as cheap and small as possible
Study collective behavior with a large quantity of robots
Acquire knowledge in highly integrated intelligent system
Provide a hardware platform for further research
Technical specifications
Main Features
Dimensions: 22 mm x 21 mm x 20 mm
Velocity: 40 mm/s
Power consumption: 12 - 17 mW
Communication: local IR 6 cm, IR & radio 10 m
Power autonomy: up to 10 hours
Main Robot
2 SWATCH motors with wheels and tires
Microcontroller PIC16LF877 with 8Kwords Flash program memory
Plastic frame and flex print with all the electronic components
4 active IR proximity sensors (reflection measurement)
NiMH rechargeable battery
Receiver for remote control
24 pin connector for extension, voltage regulator and power switch
Extension modules
Linear camera 102 pixels
Bidirectional radio communication
Tactile sensors
Zigbee ready radio module running TinyOS
Projects and applications
20 robots at Swiss Expo.02
RobOnWeb
Navigation and map building
Soccer Kit : 2 teams of 3 Alices play soccer on an A4 page
Colle
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