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https://en.wikipedia.org/wiki/Siloxane
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In organosilicon chemistry, a siloxane is an organic compound containing a functional group of two silicon atoms bound to an oxygen atom: . The parent siloxanes include the oligomeric and polymeric hydrides with the formulae and . Siloxanes also include branched compounds, the defining feature of which is that each pair of silicon centres is separated by one oxygen atom. The siloxane functional group forms the backbone of silicones , the premier example of which is polydimethylsiloxane (PDMS). The functional group (where the three Rs may be different) is called siloxy. Siloxanes are manmade and have many commercial and industrial applications because of the compounds’ hydrophobicity, low thermal conductivity, and high flexibility.
Structure
Siloxanes generally adopt structures expected for linked tetrahedral ("sp3-like") centers. The Si−O bond length is 1.64 Å (vs Si–C distance of 1.92 Å) and the Si-O-Si angle is rather open at 142.5°. By contrast, the C−O distance in a typical dialkyl ether is much shorter at 1.414(2) Å with a more acute C−O−C angle of 111°. It can be appreciated that the siloxanes would have low barriers for rotation about the Si−O bonds as a consequence of low steric hindrance. This geometric consideration is the basis of the useful properties of some siloxane-containing materials, such as their low glass transition temperatures.
Synthesis of siloxanes
The main route to siloxane functional group is by hydrolysis of silicon chlorides:
2 R3Si−
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https://en.wikipedia.org/wiki/Dan%20Farmer
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Dan Farmer (born April 5, 1962) is an American computer security researcher and programmer who was a pioneer in the development of vulnerability scanners for Unix operating systems and computer networks.
Life and career
Farmer developed his first software suite while he was a computer science student at Purdue University in 1989. Gene Spafford, one of his professors, helped him to start the project. The software, called the Computer Oracle and Password System (COPS), comprises several small, specialized vulnerability scanners designed to identify security weaknesses in one part of a Unix operating system.
In 1995, Farmer and Wietse Venema (a Dutch programmer and physicist) developed a second vulnerability scanner called the Security Administrator Tool for Analyzing Networks (SATAN). Due to a misunderstanding of SATAN's capabilities, when it was first published, some network administrators and law enforcement personnel believed that hackers would use it to identify and break into vulnerable computers. Consequently, SGI terminated Farmer's employment. However, contrary to popular opinion, SATAN did not function as an automatic hacking program that undermined network security. Rather, it operated as an audit on network security that identified vulnerabilities and made suggestions to help prevent them. No information about how security vulnerabilities could be exploited was provided by the tool. Within a few years, the use of vulnerability scanners such as SATAN became an ac
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https://en.wikipedia.org/wiki/Manipulator%20%28device%29
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In robotics, a manipulator is a device used to manipulate materials without direct physical contact by the operator. The applications were originally for dealing with radioactive or biohazardous materials, using robotic arms, or they were used in inaccessible places. In more recent developments they have been used in diverse range of applications including welding automation, robotic surgery and in space. It is an arm-like mechanism that consists of a series of segments, usually sliding or jointed called cross-slides, which grasp and move objects with a number of degrees of freedom.
In industrial ergonomics a manipulator is a lift-assist device used to help workers lift, maneuver and place articles in process that are too heavy, too hot, too large or otherwise too difficult for a single worker to manually handle. As opposed to simply vertical lift assists (cranes, hoists, etc.) manipulators have the ability to reach in to tight spaces and remove workpieces. A good example would be removing large stamped parts from a press and placing them in a rack or similar dunnage. In welding, a column boom manipulator is used to increase deposition rates, reduce human error and other costs in a manufacturing setting.
Additionally, manipulator tooling gives the lift assist the ability to pitch, roll, or spin the part for appropriate placement. An example would be removing a part from a press in the horizontal and then pitching it up for vertical placement in a rack or rolling a par
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https://en.wikipedia.org/wiki/Doublet%20state
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In quantum mechanics, a doublet is a composite quantum state of a system with an effective spin of 1/2, such that there are two allowed values of the spin component, −1/2 and +1/2. Quantum systems with two possible states are sometimes called two-level systems. Essentially all occurrences of doublets in nature arise from rotational symmetry; spin 1/2 is associated with the fundamental representation of the Lie group SU(2).
History and applications
The term "doublet" dates back to the 19th century, when it was observed that certain spectral lines of an ionized, excited gas would split into two under the influence of a strong magnetic field, in an effect known as the anomalous Zeeman effect. Such spectral lines were observed not only in the laboratory, but also in astronomical spectroscopy observations, allowing astronomers to deduce the existence of, and measure the strength of magnetic fields around the Sun, stars and galaxies. Conversely, it was the observation of doublets in spectroscopy that allowed physicists to deduce that the electron had a spin, and that furthermore, the magnitude of the spin had to be 1/2. See the history section of the article on Spin (physics) for greater detail.
Doublets continue to play an important role in physics. For example, the healthcare technology of magnetic resonance imaging is based on nuclear magnetic resonance. In this technology, a spectroscopic doublet occurs in a spin-1/2 atomic nucleus, whose doublet splitting is in the radio-fre
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https://en.wikipedia.org/wiki/Greek%20letters%20used%20in%20mathematics%2C%20science%2C%20and%20engineering
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Greek letters are used in mathematics, science, engineering, and other areas where mathematical notation is used as symbols for constants, special functions, and also conventionally for variables representing certain quantities. In these contexts, the capital letters and the small letters represent distinct and unrelated entities. Those Greek letters which have the same form as Latin letters are rarely used: capital A, B, E, Z, H, I, K, M, N, O, P, T, Y, X. Small ι, ο and υ are also rarely used, since they closely resemble the Latin letters i, o and u. Sometimes, font variants of Greek letters are used as distinct symbols in mathematics, in particular for ε/ϵ and π/ϖ. The archaic letter digamma (Ϝ/ϝ/ϛ) is sometimes used.
The Bayer designation naming scheme for stars typically uses the first Greek letter, α, for the brightest star in each constellation, and runs through the alphabet before switching to Latin letters.
In mathematical finance, the Greeks are the variables denoted by Greek letters used to describe the risk of certain investments.
Typography
The Greek letter forms used in mathematics are often different from those used in Greek-language text: they are designed to be used in isolation, not connected to other letters, and some use variant forms which are not normally used in current Greek typography.
The OpenType font format has the feature tag "mgrk" ("Mathematical Greek") to identify a glyph as representing a Greek letter to be used in mathematical (as opposed
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https://en.wikipedia.org/wiki/Indel
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Indel (insertion-deletion) is a molecular biology term for an insertion or deletion of bases in the genome of an organism. Indels ≥ 50 bases in length are classified as structural variants.
In coding regions of the genome, unless the length of an indel is a multiple of 3, it will produce a frameshift mutation. For example, a common microindel which results in a frameshift causes Bloom syndrome in the Jewish or Japanese population. Indels can be contrasted with a point mutation. An indel inserts or deletes nucleotides from a sequence, while a point mutation is a form of substitution that replaces one of the nucleotides without changing the overall number in the DNA. Indels can also be contrasted with Tandem Base Mutations (TBM), which may result from fundamentally different mechanisms. A TBM is defined as a substitution at adjacent nucleotides (primarily substitutions at two adjacent nucleotides, but substitutions at three adjacent nucleotides have been observed).
Indels, being either insertions, or deletions, can be used as genetic markers in natural populations, especially in phylogenetic studies. It has been shown that genomic regions with multiple indels can also be used for species-identification procedures.
An indel change of a single base pair in the coding part of an mRNA results in a frameshift during mRNA translation that could lead to an inappropriate (premature) stop codon in a different frame. Indels that are not multiples of 3 are particularly uncommon in cod
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https://en.wikipedia.org/wiki/Bursa%20%28disambiguation%29
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Bursa is a large city in Turkey
Bursa may also refer to:
Places and jurisdictions
Bursa Province, Asian Turkey, named after its above capital
Bursa (electoral district)
Bursa (woreda), a district in Southern Nations, Nationalities, and Peoples' Region, Ethiopia
Biology
Bursa (genus), a genus of gastropods
Bursa of Fabricius, a lymphatic organ in birds
Bursa Tumbler, a breed of domestic pigeon
Synovial bursa, a fluid filled sac located between a bone and tendon
Finance
Bursa Efek Indonesia or Indonesia Stock Exchange, previously two separate entities:
Bursa Efek Jakarta or Jakarta Stock Exchange
Bursa Efek Surabaya or Surabaya Stock Exchange
Bursa Malaysia, the Malaysian stock exchange
Tel Aviv Stock Exchange, also known as The Bursa
Other uses
Bursa (liturgy), an embroidered pouch containing the corporal used in the Holy Mass
Bursa (Romanian newspaper), published in Bucharest
Bursa (Star Wars), a fictional creature
SS Bursa, a British tanker in service 1946–1961
Bursa, a 1946 meteorite that fell in Bursa, Turkey
See also
Bursar
Bourse (disambiguation)
Brusa (disambiguation)
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https://en.wikipedia.org/wiki/Phi%20Sigma%20Rho
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Phi Sigma Rho (; also known as Phi Rho or PSR) is a social sorority for individuals who identify as female or non-binary in science, technology, engineering, and mathematics. The sorority was founded in 1984 at Purdue University. It has since expanded to more than 40 colleges across the United States.
History
Phi Sigma Rho was founded on September 24, 1984, at Purdue University by Rashmi Khanna and Abby McDonald. Khanna and McDonald were unable to participate in traditional sorority rush due to the demands of the sororities and their engineering program, so they decided to start a new sorority that would take their academic program's demands into consideration.
The Alpha chapter at Purdue University was founded with ten charter members: Gail Bonney, Anita Chatterjea, Ann Cullinan, Pam Kabbes, Rashmi Khanna, Abby McDonald, Christine Mooney, Tina Kershner, Michelle Self, and Kathy Vargo.
Phi Sigma Rho accepts students pursuing degrees in science, technology, engineering, and mathematics who identify as female or who identify as non-binary. The sorority made the decision to include non-binary students in all chapters in the summer of 2021.
Phi Sigma Rho has grown more than 40 chapters nationally. Its headquarters is located in Northville, Michigan. Its online magazine is The Key.
Symbols
The colors of Phi Sigma Rho are wine red and silver. The sorority's flower is the orchid, and its jewel is the pearl. Its mascot is Sigmand the penguin. Its motto is "together we build the
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https://en.wikipedia.org/wiki/Regnum
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Regnum may refer to:
Latin for kingdom or dominion, see realm
Regnum, Latin word for Kingdom (biology)
REGNUM News Agency, a Russian news agency
Champions of Regnum, a computer game
An online database for PhyloCode
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https://en.wikipedia.org/wiki/Stefan%20Rahmstorf
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Stefan Rahmstorf (born 22 February 1960) is a German oceanographer and climatologist. Since 2000, he has been a Professor of Physics of the Oceans at Potsdam University. He studied physical oceanography at Bangor University and received his Ph.D. in oceanography from Victoria University of Wellington (1990). His work focuses on the role of ocean currents in climate change. He was one of the lead authors of the IPCC Fourth Assessment Report.
Public role
Rahmstorf is a co-founder of the blog Real Climate, which has been described by Nature as one of the top-5 science blogs in 2006, and included among the 15 best environmental websites by Time in 2008. He also co-founded the German blog KlimaLounge. KlimaLounge won the 3rd prize of the science blog award of 2013. He is a frequent contributor of articles on climate and climate change/global warming in the popular press, some of which are internationally syndicated via Project Syndicate. He writes a regular column in the German environmental magazine Zeo2, and has published the children's science book Wolken, Wind und Wetter (Clouds, Wind, and Weather) on weather and climate. The book was selected as Environmental Book of the Month for January 2012 by the Deutsche Umweltstiftung. In addition, it was later voted Environmental Book of the Year 2012.
Rahmstorf has commented on climate change and climate policy on TV and radio. He was portrayed as one of the world's 10 leading climate scientists by the Financial Times in 2009. The
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https://en.wikipedia.org/wiki/Christian%20Mayer%20%28astronomer%29
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Christian Mayer (20 August 1719 Mederitz – 16 April 1783 in Mannheim) was a Moravian-German Catholic priest, astronomer and teacher.
Life
He was born in Mederitz, Moravia. He became educated in Greek, Latin, mathematics,
philosophy, and theology, although his place of studies is unknown. In his early twenties he decided to become a Jesuit, a path which caused him to leave his home due to the disapproval of his father. He entered the Society of Jesus in Mannheim in 1745. After completing his training he began teaching humanities.
By 1752 his reputation was such that he was selected as a professor of mathematics and physics at Heidelberg. By this age, however, he had developed a strong interest in astronomy. He was appointed Court Astronomer at Mannheim, and was tasked with selecting the instruments for the new observatories at Schwetzingen and Mannheim. With these completed, he was able to pursue his astronomical studies, and published numerous works. In 1769 he was invited to St. Petersburg to observe the transit of Venus, which he did together with Anders Johan Lexell. In 1773, the Jesuit order was dissolved by Pope Clement XIV, and consequently he was removed as Court Astronomer. However he was still able to continue his astronomical observations and studies. He applied for and was granted in December 1765 a Fellowship of the Royal Society and in 1768 he was elected to the American Philosophical Society.
He is most noted for pioneering the study of binary stars, althoug
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https://en.wikipedia.org/wiki/Eisenstein%27s%20theorem
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In mathematics, Eisenstein's theorem, named after the German mathematician Gotthold Eisenstein, applies to the coefficients of any power series which is an algebraic function with rational number coefficients. Through the theorem, it is readily demonstrable, for example, that the exponential function must be a transcendental function.
Theorem
Suppose that
is a formal power series with rational coefficients an, which has a non-zero radius of convergence in the complex plane, and within it represents an analytic function that is in fact an algebraic function. Then Eisenstein's theorem states that there exists a non-zero integer A, such that Anan are all integers.
This has an interpretation in terms of p-adic numbers: with an appropriate extension of the idea, the p-adic radius of convergence of the series is at least 1, for almost all p (i.e., the primes outside a finite set S). In fact that statement is a little weaker, in that it disregards any initial partial sum of the series, in a way that may vary according to p. For the other primes the radius is non-zero.
History
Eisenstein's original paper is the short communication
Über eine allgemeine Eigenschaft der Reihen-Entwicklungen aller algebraischen Functionen
(1852), reproduced in Mathematische Gesammelte Werke, Band II, Chelsea Publishing Co., New York, 1975,
p. 765–767.
More recently, many authors have investigated precise and effective bounds quantifying the above almost all.
See, e.g., Sections 11.4 and 11.55 of th
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https://en.wikipedia.org/wiki/Molar%20mass%20distribution
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In polymer chemistry, the molar mass distribution (or molecular weight distribution) describes the relationship between the number of moles of each polymer species () and the molar mass () of that species. In linear polymers, the individual polymer chains rarely have exactly the same degree of polymerization and molar mass, and there is always a distribution around an average value. The molar mass distribution of a polymer may be modified by polymer fractionation.
Definitions of molar mass average
Different average values can be defined, depending on the statistical method applied. In practice, four averages are used, representing the weighted mean taken with the mole fraction, the weight fraction, and two other functions which can be related to measured quantities:
Number average molar mass (), also loosely referred to as number average molecular weight (NAMW).
Mass average molar mass (), where stands for weight; also commonly referred to as weight average or weight average molecular weight (WAMW).
Z-average molar mass (), where stands for centrifugation ().
Viscosity average molar mass ().
Here, is the exponent in the Mark–Houwink equation that relates the intrinsic viscosity to molar mass.
Measurement
These different definitions have true physical meaning because different techniques in physical polymer chemistry often measure just one of them. For instance, osmometry measures number average molar mass and small-angle laser light scattering measures mass average
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https://en.wikipedia.org/wiki/CAAT%20box
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In molecular biology, a CCAAT box (also sometimes abbreviated a CAAT box or CAT box) is a distinct pattern of nucleotides with GGCCAATCT consensus sequence that occur upstream by 60–100 bases to the initial transcription site. The CAAT box signals the binding site for the RNA transcription factor, and is typically accompanied by a conserved consensus sequence. It is an invariant DNA sequence at about minus 70 base pairs from the origin of transcription in many eukaryotic promoters. Genes that have this element seem to require it for the gene to be transcribed in sufficient quantities. It is frequently absent from genes that encode proteins used in virtually all cells. This box along with the GC box is known for binding general transcription factors. Both of these consensus sequences belong to the regulatory promoter. Full gene expression occurs when transcription activator proteins bind to each module within the regulatory promoter. Protein specific binding is required for the CCAAT box activation. These proteins are known as CCAAT box binding proteins/CCAAT box binding factors.
A CCAAT box is a feature frequently found before eukaryote coding regions, but is not found in prokaryotes.
Consensus sequence
In the direction of transcription of the template strand, the consensus sequence, or the calculated order of the most frequent residues, for the CAAT box was 3'-TG ATTGG (T/C)(T/C)(A/G)-5'. The use of parentheses denotes that either base is present, but it is not specified a
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https://en.wikipedia.org/wiki/Moyal%20product
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In mathematics, the Moyal product (after José Enrique Moyal; also called the star product or Weyl–Groenewold product, after Hermann Weyl and Hilbrand J. Groenewold) is an example of a phase-space star product. It is an associative, non-commutative product, , on the functions on , equipped with its Poisson bracket (with a generalization to symplectic manifolds, described below). It is a special case of the -product of the "algebra of symbols" of a universal enveloping algebra.
Historical comments
The Moyal product is named after José Enrique Moyal, but is also sometimes called the Weyl–Groenewold product as it was introduced by H. J. Groenewold in his 1946 doctoral dissertation, in a trenchant appreciation of the Weyl correspondence. Moyal actually appears not to know about the product in his celebrated article and was crucially lacking it in his legendary correspondence with Dirac, as illustrated in his biography. The popular naming after Moyal appears to have emerged only in the 1970s, in homage to his flat phase-space quantization picture.
Definition
The product for smooth functions and on takes the form
where each is a certain bidifferential operator of order characterized by the following properties (see below for an explicit formula):
Deformation of the pointwise product — implicit in the formula above.
Deformation of the Poisson bracket, called Moyal bracket.
The 1 of the undeformed algebra is also the identity in the new algebra.
The complex conjugat
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https://en.wikipedia.org/wiki/Critical%20period
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In developmental psychology and developmental biology, a critical period is a maturational stage in the lifespan of an organism during which the nervous system is especially sensitive to certain environmental stimuli. If, for some reason, the organism does not receive the appropriate stimulus during this "critical period" to learn a given skill or trait, it may be difficult, ultimately less successful, or even impossible, to develop certain associated functions later in life. Functions that are indispensable to an organism's survival, such as vision, are particularly likely to develop during critical periods. "Critical period" also relates to the ability to acquire one's first language. Researchers found that people who passed the "critical period" would not acquire their first language fluently.
Some researchers differentiate between 'strong critical periods' and 'weak critical periods' (a.k.a. 'sensitive' periods) — defining 'weak critical periods' / 'sensitive periods' as more extended periods, after which learning is still possible. Other researchers consider these the same phenomenon.
For example, the critical period for the development of a human child's binocular vision is thought to be between three and eight months, with sensitivity to damage extending up to at least three years of age. Further critical periods have been identified for the development of hearing and the vestibular system.
Strong versus weak critical periods
Examples of strong critical periods incl
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https://en.wikipedia.org/wiki/Radical%20polymerization
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In polymer chemistry, free-radical polymerization (FRP) is a method of polymerization by which a polymer forms by the successive addition of free-radical building blocks (repeat units). Free radicals can be formed by a number of different mechanisms, usually involving separate initiator molecules. Following its generation, the initiating free radical adds (nonradical) monomer units, thereby growing the polymer chain.
Free-radical polymerization is a key synthesis route for obtaining a wide variety of different polymers and materials composites. The relatively non-specific nature of free-radical chemical interactions makes this one of the most versatile forms of polymerization available and allows facile reactions of polymeric free-radical chain ends and other chemicals or substrates. In 2001, 40 billion of the 110 billion pounds of polymers produced in the United States were produced by free-radical polymerization.
Free-radical polymerization is a type of chain-growth polymerization, along with anionic, cationic and coordination polymerization.
Initiation
Initiation is the first step of the polymerization process. During initiation, an active center is created from which a polymer chain is generated. Not all monomers are susceptible to all types of initiators. Radical initiation works best on the carbon–carbon double bond of vinyl monomers and the carbon–oxygen double bond in aldehydes and ketones. Initiation has two steps. In the first step, one or two radicals are creat
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https://en.wikipedia.org/wiki/Rishon%20model
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The Harari–Shupe preon model (also known as rishon model, RM) is the earliest effort to develop a preon model to explain the phenomena appearing in the Standard Model (SM) of particle physics. It was first developed independently by Haim Harari and by Michael A. Shupe and later expanded by Harari and his then-student Nathan Seiberg.
The model
The model has two kinds of fundamental particles called rishons (which means "primary" in Hebrew). They are T ("Third" since it has an electric charge of + e, or Tohu which means "unformed" in Hebrew) and V ("Vanishes", since it is electrically neutral, or Vohu which means "void" in Hebrew). All leptons and all flavours of quarks are three-rishon ordered triplets. These groups of three rishons have spin-. They are as follows:
TTT = positron (anti-electron);
VVV = electron neutrino;
TTV, TVT and VTT = three colours of up quarks;
VVT, VTV and TVV = three colours of down antiquarks.
Each rishon has a corresponding antiparticle. Hence:
= electron;
= electron antineutrino;
, , = three colours of up antiquarks;
, , = three colours of down quarks.
The W+ boson = TTTVVV;
The W− boson = .
Note that:
Matter and antimatter are equally abundant in nature in the RM. This still leaves open the question of why , , and TTV etc. are common whereas TTT, TVV, and etc. are rare.
Higher generation leptons and quarks are presumed to be excited states of first generation leptons and quarks, but those states are not specified.
The simple RM
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https://en.wikipedia.org/wiki/Fundamental%20theorem%20of%20Galois%20theory
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In mathematics, the fundamental theorem of Galois theory is a result that describes the structure of certain types of field extensions in relation to groups. It was proved by Évariste Galois in his development of Galois theory.
In its most basic form, the theorem asserts that given a field extension E/F that is finite and Galois, there is a one-to-one correspondence between its intermediate fields and subgroups of its Galois group. (Intermediate fields are fields K satisfying F ⊆ K ⊆ E; they are also called subextensions of E/F.)
Explicit description of the correspondence
For finite extensions, the correspondence can be described explicitly as follows.
For any subgroup H of Gal(E/F), the corresponding fixed field, denoted EH, is the set of those elements of E which are fixed by every automorphism in H.
For any intermediate field K of E/F, the corresponding subgroup is Aut(E/K), that is, the set of those automorphisms in Gal(E/F) which fix every element of K.
The fundamental theorem says that this correspondence is a one-to-one correspondence if (and only if) E/F is a Galois extension.
For example, the topmost field E corresponds to the trivial subgroup of Gal(E/F), and the base field F corresponds to the whole group Gal(E/F).
The notation Gal(E/F) is only used for Galois extensions. If E/F is Galois, then Gal(E/F) = Aut(E/F). If E/F is not Galois, then the "correspondence" gives only an injective (but not surjective) map from to , and a surjective (but not injective) m
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https://en.wikipedia.org/wiki/Anne%20Wheeler
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Anne Wheeler, OC, (born September 23, 1946) is a Canadian film and television writer, producer, and director.
Biography
Graduating in Mathematics from the University of Alberta she was a computer programmer before traveling abroad. Her years of travels inspired her to become a storyteller and when she returned she joined a group of old friends to form a film collective. From 1975 to 1985 she worked for the NFB where she made her first feature film, A War Story (1981), which was about her father, Ben Wheeler and his time as a doctor in a P.O.W. camp during World War II. The war is a common theme in her work and she revisited it later in her films Bye Bye Blues (1989) and The War Between Us (1995). Her first non-NFB film was Loyalties in 1986.
In addition to her films, Wheeler has directed episodes of Anne with an E, Private Eyes, Strange Empire, The Romeo Section, The Guard, This Is Wonderland, Da Vinci's Inquest, and Cold Squad.
Awards and honors
Wheeler has been nominated four times for the Genie Award for Best Achievement in Direction for her films Loyalties (1986), Cowboys Don't Cry (1988), Bye Bye Blues (1989), and Suddenly Naked (2001). Her 1998 television miniseries, The Sleep Room, won Gemini awards for best television movie and best direction.
In 2017 Wheeler won a Leo Award for Best Direction (Television Film) for the Hallmark movie Stop the Wedding.
Wheeler was made an Officer of the Order of Canada in 1995. In 2012 she received the Queen Elizabeth II Diamond
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https://en.wikipedia.org/wiki/Tetramethylsilane
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Tetramethylsilane (abbreviated as TMS) is the organosilicon compound with the formula Si(CH3)4. It is the simplest tetraorganosilane. Like all silanes, the TMS framework is tetrahedral. TMS is a building block in organometallic chemistry but also finds use in diverse niche applications.
Synthesis and reactions
TMS is a by-product of the production of methyl chlorosilanes, SiClx(CH3)4−x, via the direct process of reacting methyl chloride with silicon. The more useful products of this reaction are those for x = 1 (trimethylsilyl chloride), 2 (dimethyldichlorosilane), and 3 (methyltrichlorosilane).
TMS undergoes deprotonation upon treatment with butyllithium to give (H3C)3SiCH2Li. The latter, trimethylsilylmethyl lithium, is a relatively common alkylating agent.
In chemical vapor deposition, TMS is the precursor to silicon dioxide or silicon carbide, depending on the deposition conditions. In the formation of silicon carbide, carbosilanes, such as 1,3,5,7-tetramethyl-1,3,5,7-tetrasilaadamantane, are observed as intermediates.
Uses in NMR spectroscopy
Tetramethylsilane is the accepted internal standard for calibrating chemical shift for 1H, 13C and 29Si NMR spectroscopy in organic solvents (where TMS is soluble). In water, where it is not soluble, sodium salts of DSS, 2,2-dimethyl-2-silapentane-5-sulfonate, are used instead. Because of its high volatility, TMS can easily be evaporated, which is convenient for recovery of samples analyzed by NMR spectroscopy.
Because all
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https://en.wikipedia.org/wiki/Incompatible%20element
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In petrology and geochemistry, an incompatible element is one that is unsuitable in size and/or charge to the cation sites of the minerals of which it is included. It is defined by the partition coefficient between rock-forming minerals and melt being much smaller than 1.
During the fractional crystallization of magma and magma generation by the partial melting of the Earth's mantle and crust, elements that have difficulty in entering cation sites of the minerals are concentrated in the melt phase of magma (liquid phase).
Two groups of incompatible elements that have difficulty entering the solid phase are known by acronyms. One group includes elements having large ionic radius, such as potassium, rubidium, caesium, strontium, barium (called LILE, or large-ion lithophile elements), and the other group includes elements of large ionic valences (or high charges), such as zirconium, niobium, hafnium, rare-earth elements (REE), thorium, uranium and tantalum (called HFSE, or high-field-strength elements).
Another way to classify incompatible elements is by mass (lanthanide series): light rare-earth elements (LREE) are La, Ce, Pr, Nd, and Sm, and heavy rare-earth elements (HREE) are Eu–Lu. Rocks or magmas that are rich, or only slightly depleted, in light rare-earth elements are referred to as "fertile", and those with strong depletions in LREE are referred to as "depleted".
See also
Compatibility (geochemistry)
References
Geochemistry
Igneous petrology
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https://en.wikipedia.org/wiki/Heat%20capacity%20ratio
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In thermal physics and thermodynamics, the heat capacity ratio, also known as the adiabatic index, the ratio of specific heats, or Laplace's coefficient, is the ratio of the heat capacity at constant pressure () to heat capacity at constant volume (). It is sometimes also known as the isentropic expansion factor and is denoted by (gamma) for an ideal gas or (kappa), the isentropic exponent for a real gas. The symbol is used by aerospace and chemical engineers.
where is the heat capacity, the molar heat capacity (heat capacity per mole), and the specific heat capacity (heat capacity per unit mass) of a gas. The suffixes and refer to constant-pressure and constant-volume conditions respectively.
The heat capacity ratio is important for its applications in thermodynamical reversible processes, especially involving ideal gases; the speed of sound depends on this factor.
Thought experiment
To understand this relation, consider the following thought experiment. A closed pneumatic cylinder contains air. The piston is locked. The pressure inside is equal to atmospheric pressure. This cylinder is heated to a certain target temperature. Since the piston cannot move, the volume is constant. The temperature and pressure will rise. When the target temperature is reached, the heating is stopped. The amount of energy added equals , with representing the change in temperature.
The piston is now freed and moves outwards, stopping as the pressure inside the chamber reaches at
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https://en.wikipedia.org/wiki/Motion%20control
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Motion control is a sub-field of automation, encompassing the systems or sub-systems involved in moving parts of machines in a controlled manner. Motion control systems are extensively used in a variety of fields for automation purposes, including precision engineering, micromanufacturing, biotechnology, and nanotechnology. The main components involved typically include a motion controller, an energy amplifier, and one or more prime movers or actuators. Motion control may be open loop or closed loop. In open loop systems, the controller sends a command through the amplifier to the prime mover or actuator, and does not know if the desired motion was actually achieved. Typical systems include stepper motor or fan control. For tighter control with more precision, a measuring device may be added to the system (usually near the end motion). When the measurement is converted to a signal that is sent back to the controller, and the controller compensates for any error, it becomes a Closed loop System.
Typically the position or velocity of machines are controlled using some type of device such as a hydraulic pump, linear actuator, or electric motor, generally a servo. Motion control is an important part of robotics and CNC machine tools, however in these instances it is more complex than when used with specialized machines, where the kinematics are usually simpler. The latter is often called General Motion Control (GMC). Motion control is widely used in the packaging, printing, text
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https://en.wikipedia.org/wiki/Dependent%20type
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In computer science and logic, a dependent type is a type whose definition depends on a value. It is an overlapping feature of type theory and type systems. In intuitionistic type theory, dependent types are used to encode logic's quantifiers like "for all" and "there exists". In functional programming languages like Agda, ATS, Coq, F*, Epigram, and Idris, dependent types help reduce bugs by enabling the programmer to assign types that further restrain the set of possible implementations.
Two common examples of dependent types are dependent functions and dependent pairs. The return type of a dependent function may depend on the value (not just type) of one of its arguments. For instance, a function that takes a positive integer may return an array of length , where the array length is part of the type of the array. (Note that this is different from polymorphism and generic programming, both of which include the type as an argument.) A dependent pair may have a second value the type of which depends on the first value. Sticking with the array example, a dependent pair may be used to pair an array with its length in a type-safe way.
Dependent types add complexity to a type system. Deciding the equality of dependent types in a program may require computations. If arbitrary values are allowed in dependent types, then deciding type equality may involve deciding whether two arbitrary programs produce the same result; hence the decidability of type checking may depend on the give
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https://en.wikipedia.org/wiki/Bernard%20Lemaire
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Bernard Lemaire, (born May 6, 1936) is a Canadian businessman. He was the Chairman of the Board of Cascades Inc., a Canadian manufacturer of packaging products, tissue products and fine papers products.
Biography
Born in Drummondville, Quebec, he studied civil engineering at the Université de Sherbrooke and McGill University. In 1960, he joined the family recycling business, Drummond Pulp and Fiber. In 1963, along with his father and brother, Laurent, he founded Papier Cascades Inc. (which later became Cascades Inc.). He was President and Chief Executive Officer of the company until 1992.
Under Lemaire's presidency Cascades grew from a small paper mill in Kingsey Falls, Quebec, into a multi-national company with 90 plants and 11,000 employees in Canada, the United States and France.
In 1987, he was made an Officer of the Order of Canada, the centrepiece of Canada's honours system which recognizes a lifetime of achievement and merit of a high degree, especially in service to Canada or to humanity at large. In 2002, he was awarded the Chevalier de l'Ordre national de la Légion d'honneur of France.
Upon his retirement from Cascades, Lemaire began a cattle ranch that quickly grew to 1,000 head of highland cattle. He continues to market his natural, hormone-free cattle at the local grocery stores, IGA, Avril Health Supermarkets, butchers and restaurants.
References
1936 births
Living people
Canadian businesspeople
Officers of the Order of Canada
Papermakers
People from Dru
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https://en.wikipedia.org/wiki/Tim%20Willits
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Tim Willits is the former studio director, co-owner, and level designer of id Software. As of August 2019, Willits is the chief creative officer at Saber Interactive. He became a Director of 3D Realms with Saber Interactive’s acquisition of the company.
Biography
Willits is a computer science and business graduate of the University of Minnesota and a former member of the University of Minnesota Army ROTC program. Willits was the battalion cadet-command sergeant major (C/CSM) during his junior year and attended ROTC Advanced Camp at Fort Lewis, Washington during the summer between his junior and senior years of college. After an injury during the summer, Willits completed two rotations, being assigned to both the first and seventh cadet regiments during that summer. He held the rank of cadet-major (C/MAJ) during his senior year and was assigned as the battalion training officer.
Personal life
Married for the second time in 2009, Willits currently lives in a Dallas suburb with his wife, Alison Barron Willits. Together, both of them have triplets.
Career
Willits has stated in numerous interviews that he was inspired to make video games when he downloaded a shareware version of Doom. He played the first room of E1M1, thinking that was the entire demo, then, discovering a door that led the player to the other rooms. It was that moment when the door opened that Willits decided he wanted to make video games. He joined id Software in 1995 after impressing the owners and developm
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https://en.wikipedia.org/wiki/Sharon%20Hayes
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Sharon Ruth Hayes (born January 15, 1948) is a Canadian former politician.
Born in Toronto, Ontario, she represented the riding of Port Moody—Coquitlam from 1993 to 1997 for the Reform Party of Canada.
Hayes is a graduate of the Honours Math and Computer Science program at the University of Waterloo; while enrolled there, she worked as a co-op student with the Toronto Stock Exchange and IBM. After graduation, she worked as a program analyst at the University of Guelph and then as a Sessional Instructor in computer science at Simon Fraser University. She married Douglas Hayes June 13, 1970.
Her election victory in 1993 came over the incumbent, Ian Waddell of the New Democratic Party, and challenger Celso Boscariol, B.C. president of the Liberal Party of Canada. As one of 52 Reform MPs, she served as Chair of the party's Family Caucus and critic on Human Rights and Status of Women. She was assistant critic for Health (1995-'96) and Human Resources (1997), and a member of the Standing Committees on Health (1994-'97), Citizenship and Immigration (1994-'96) and Human Rights (1996-'97), and of the sub-Committee on HIV/AIDS (1994-'96). While in office, Hayes joined many of her Reform colleagues in donating 10% of their salary to charity and opting out of the MP pension plan.
Hayes was best known as a socially conservative advocate for family issues. She crafted the RPC's response to parliamentary initiatives on family and the definition of family, age of consent, Child Care T
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https://en.wikipedia.org/wiki/Arithmetic%20genus
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In mathematics, the arithmetic genus of an algebraic variety is one of a few possible generalizations of the genus of an algebraic curve or Riemann surface.
Projective varieties
Let X be a projective scheme of dimension r over a field k, the arithmetic genus of X is defined asHere is the Euler characteristic of the structure sheaf .
Complex projective manifolds
The arithmetic genus of a complex projective manifold
of dimension n can be defined as a combination of Hodge numbers, namely
When n=1, the formula becomes . According to the Hodge theorem, . Consequently , where g is the usual (topological) meaning of genus of a surface, so the definitions are compatible.
When X is a compact Kähler manifold, applying hp,q = hq,p recovers the earlier definition for projective varieties.
Kähler manifolds
By using hp,q = hq,p for compact Kähler manifolds this can be
reformulated as the Euler characteristic in coherent cohomology for the structure sheaf :
This definition therefore can be applied to some other
locally ringed spaces.
See also
Genus (mathematics)
Geometric genus
References
Further reading
Topological methods of algebraic geometry
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https://en.wikipedia.org/wiki/IEEE%20Spectrum
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IEEE Spectrum is a magazine edited by the Institute of Electrical and Electronics Engineers.
The first issue of IEEE Spectrum was published in January 1964 as a successor to Electrical Engineering.
In 2010, IEEE Spectrum was the recipient of Utne Reader magazine's Utne Independent Press Award for Science/Technology Coverage. In 2012, IEEE Spectrum was selected as the winner of the National Magazine Awards "General Excellence Among Thought Leader Magazines" category.
References
External links
Monthly magazines published in the United States
Science and technology magazines published in the United States
Engineering magazines
Spectrum
Magazines established in 1964
Magazines published in New York City
Open access publications
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https://en.wikipedia.org/wiki/Metallurgical%20Laboratory
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The Metallurgical Laboratory (or Met Lab) was a scientific laboratory at the University of Chicago that was established in February 1942 to study and use the newly discovered chemical element plutonium. It researched plutonium's chemistry and metallurgy, designed the world's first nuclear reactors to produce it, and developed chemical processes to separate it from other elements. In August 1942 the lab's chemical section was the first to chemically separate a weighable sample of plutonium, and on 2 December 1942, the Met Lab produced the first controlled nuclear chain reaction, in the reactor Chicago Pile-1, which was constructed under the stands of the university's old football stadium, Stagg Field.
The Metallurgical Laboratory was established as part of the Metallurgical Project, also known as the "Pile" or "X-10" Project, headed by Chicago professor Arthur H. Compton, a Nobel Prize laureate. In turn, this was part of the Manhattan Project – the Allied effort to develop the atomic bomb during World War II. The Metallurgical Laboratory was successively led by Richard L. Doan, Samuel K. Allison, Joyce C. Stearns and Farrington Daniels. Scientists who worked there included Enrico Fermi, James Franck, Eugene Wigner and Glenn Seaborg. At its peak on 1 July 1944, it had 2,008 staff.
Chicago Pile-1 was soon moved by the lab to Site A, a more remote location in the Argonne Forest preserves, where the original materials were used to build an improved Chicago Pile-2 to be employed
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https://en.wikipedia.org/wiki/Critical%20point%20%28mathematics%29
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Critical point is a term used in many branches of mathematics.
When dealing with functions of a real variable, a critical point is a point in the domain of the function where the function is either not differentiable or the derivative is equal to zero. Similarly, when dealing with complex variables, a critical point is a point in the function's domain where it is either not holomorphic or the derivative is equal to zero. Likewise, for a function of several real variables, a critical point is a value in its domain where the gradient is undefined or is equal to zero.
The value of the function at a critical point is a critical value.
This sort of definition extends to differentiable maps between and a critical point being, in this case, a point where the rank of the Jacobian matrix is not maximal. It extends further to differentiable maps between differentiable manifolds, as the points where the rank of the Jacobian matrix decreases. In this case, critical points are also called bifurcation points.
In particular, if is a plane curve, defined by an implicit equation , the critical points of the projection onto the -axis, parallel to the -axis are the points where the tangent to are parallel to the -axis, that is the points where
In other words, the critical points are those where the implicit function theorem does not apply.
The notion of a critical point allows the mathematical description of an astronomical phenomenon that was unexplained before the time of Copernicus
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https://en.wikipedia.org/wiki/Feza%20G%C3%BCrsey
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Feza Gürsey (; April 7, 1921 – April 13, 1992) was a Turkish mathematician and physicist. Among his contributions to theoretical physics, his work on the chiral model and on SU(6) symmetry of the quark model are the most well-known.
Early life
Feza Gürsey was born on April 7, 1921, in Istanbul, to Reşit Süreyya Gürsey, a military physician, and Remziye Hisar, a chemist and a pioneering Turkish scientist. He graduated from Galatasaray High School in 1940, and received his degree in Mathematics – Physics from Istanbul University in 1944.
Career
Through a scholarship from the Turkish Ministry of Education he received while he was an assistant in Istanbul University, he pursued a doctorate degree at the Imperial College London in the United Kingdom. He completed his work on the application of quaternions to quantum field theory in 1950. After spending the period from 1950 to 1951 in postdoctoral research at Cambridge University, he worked as an assistant at Istanbul University, where he married Suha Pamir, also a physics assistant, in 1952, and in 1953 he acquired the title of associate professor.
During 1957–1961 he worked at Brookhaven National Laboratory, Institute for Advanced Study in Princeton, New Jersey, and Columbia University. In 1960s, he worked on the nonlinear chiral Lagrangian, and produced results of relevance to quantum chromodynamics.
Returning to Turkey in 1961, he accepted the title of professor from Middle East Technical University (METU) and took part i
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https://en.wikipedia.org/wiki/Everybody%27s%20Golf%204
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, known in the PAL region as Everybody's Golf (Everybody's Golf 2004 in Australia), and in North America as Hot Shots Golf Fore!, is the fourth game in the Everybody's Golf series and the second released for PlayStation 2.
Features
This game delivers more realistic physics, sharper graphics, more golfers, caddies and courses than before. Miniature golf games and online play for players with the Network Adaptor are also driving features. The developers increased the overall number of characters from 15 to 24, added more caddies (10 in all) and boosted the number of courses from six to 15. Of these 15 courses, 10 are new, while five are returning favorites from the previous game. The game also features a Tournament mode where up to 32 players can compete against each other. Cameo roles as playable characters in the North American and PAL versions are unlockable characters Ratchet (from the Ratchet & Clank series) and Jak (from the Jak and Daxter series, as he would later appear in Jak 3). Ratchet and Jak's caddies are Clank and Daxter, respectively. A Pipo Monkey (from the Ape Escape series) is an unlockable caddie in the Japanese and PAL versions only. The PAL version seems to have the largest character roster overall.
Everybody's Golf 4 implements the "Everybody's Points" system where players earn and spend points to unlock new gear and extras. Several different modes of play are available and include Tour (full season of tournaments), Tournament (plug and play instant acti
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https://en.wikipedia.org/wiki/Ion%20trap
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An ion trap is a combination of electric and/or magnetic fields used to capture charged particles — known as ions — often in a system isolated from an external environment. Atomic and molecular ion traps have a number of applications in physics and chemistry such as precision mass spectrometry, improved atomic frequency standards, and quantum computing. In comparison to neutral atom traps, ion traps have deeper trapping potentials (up to several electronvolts) that do not depend on the internal electronic structure of a trapped ion. This makes ion traps more suitable for the study of light interactions with single atomic systems. The two most popular types of ion traps are the Penning trap, which forms a potential via a combination of static electric and magnetic fields, and the Paul trap which forms a potential via a combination of static and oscillating electric fields.
Penning traps can be used for precise magnetic measurements in spectroscopy. Studies of quantum state manipulation most often use the Paul trap. This may lead to a trapped ion quantum computer and has already been used to create the world's most accurate atomic clocks. Electron guns (a device emitting high-speed electrons, used in CRTs) can use an ion trap to prevent degradation of the cathode by positive ions.
History
The physical principles of ion traps were first explored by F. M. Penning (1894–1953), who observed that electrons released by the cathode of an ionization vacuum gauge follow a long cycloi
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https://en.wikipedia.org/wiki/Fredholm%27s%20theorem
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In mathematics, Fredholm's theorems are a set of celebrated results of Ivar Fredholm in the Fredholm theory of integral equations. There are several closely related theorems, which may be stated in terms of integral equations, in terms of linear algebra, or in terms of the Fredholm operator on Banach spaces.
The Fredholm alternative is one of the Fredholm theorems.
Linear algebra
Fredholm's theorem in linear algebra is as follows: if M is a matrix, then the orthogonal complement of the row space of M is the null space of M:
Similarly, the orthogonal complement of the column space of M is the null space of the adjoint:
Integral equations
Fredholm's theorem for integral equations is expressed as follows. Let be an integral kernel, and consider the homogeneous equations
and its complex adjoint
Here, denotes the complex conjugate of the complex number , and similarly for . Then, Fredholm's theorem is that, for any fixed value of , these equations have either the trivial solution or have the same number of linearly independent solutions , .
A sufficient condition for this theorem to hold is for to be square integrable on the rectangle (where a and/or b may be minus or plus infinity).
Here, the integral is expressed as a one-dimensional integral on the real number line. In Fredholm theory, this result generalizes to integral operators on multi-dimensional spaces, including, for example, Riemannian manifolds.
Existence of solutions
One of Fredholm's theorems, closely
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https://en.wikipedia.org/wiki/Primal
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Primal may refer to:
Psychotherapy
Primal, the core concept in primal therapy, denotes the full reliving and cathartic release of an early traumatic experience
Primal scene (in psychoanalysis), refers to the witnessing by a young child of a sex act, usually between the parents, which traumatizes the child
Mathematics
Primal, an old mathematics term for a projective hypersurface
Primal problem, a component of the duality principle in mathematical optimization theory
Entertainment
"Primal" (Eureka episode), an episode of TV series Eureka
Primal (video game), an action video game for the PlayStation 2
Primal (TV series), a 2019 animated television series
Primal (2019 film), a 2019 film starring Nicolas Cage
Optimus Primal, a character in Transformers
The Lost Tribe (2010 film), a film whose Australian DVD was entitled Primal
Primal (2010 film), an Australian horror film directed by Josh Reed
Far Cry Primal, a 2016 video game
Other
Primal cut, several types of cuts of meat
Primal Pictures, the producer of 3D Interactive Anatomy Software
See also
Primal Fear (disambiguation)
Prime (disambiguation)
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https://en.wikipedia.org/wiki/DCR
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DCR may refer to:
Computing
.dcr, a raw image format
Decision Composite Residuosity in cryptography, see Computational hardness assumption
Design Change request, also Document Change request and Database Change request
Device control register, a hardware register that controls some computer hardware device like a peripheral or an expansion card
Railways
DCRail, a British freight operating company
Delmarva Central Railroad, a short-line railroad serving Delaware, Maryland, and Virginia on the Delmarva Peninsula
Dubois County Railroad, a Class III short-line railroad serving Dubois County in southern Indiana, United States
Engineering
DC Resistance of an inductor, see Equivalent series resistance
Direct-conversion receiver
Dynamic compression ratio, referring to the compression ratio of a combustion engine
Other
Dacryocystorhinostomy, a surgical procedure to restore the flow of tears into the nose
Dale Coyne Racing, an American auto racing team
Debt Coverage Ratio, another term for Debt service coverage ratio (DSCR)
Digital cable ready, indicating that a television is capable of receiving cable TV without a set-top box
Deglaciation Climate Reversal, see Younger Dryas
Department of Conservation and Recreation (Massachusetts), a state agency best known for its parks and parkways
Diploma of the College of Radiographers, abbreviated as DC(R), a qualification that was formerly awarded by the College of Radiographers, see Society and College of Radiographers
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https://en.wikipedia.org/wiki/Product%20order
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In mathematics, given a partial order and on a set and , respectively, the product order (also called the coordinatewise order or componentwise order) is a partial ordering on the Cartesian product Given two pairs and in declare that if and
Another possible ordering on is the lexicographical order, which is a total ordering. However the product order of two total orders is not in general total; for example, the pairs and are incomparable in the product order of the ordering with itself. The lexicographic combination of two total orders is a linear extension of their product order, and thus the product order is a subrelation of the lexicographic order.
The Cartesian product with the product order is the categorical product in the category of partially ordered sets with monotone functions.
The product order generalizes to arbitrary (possibly infinitary) Cartesian products.
Suppose is a set and for every is a preordered set.
Then the on is defined by declaring for any and in that
if and only if for every
If every is a partial order then so is the product preorder.
Furthermore, given a set the product order over the Cartesian product can be identified with the inclusion ordering of subsets of
The notion applies equally well to preorders. The product order is also the categorical product in a number of richer categories, including lattices and Boolean algebras.
References
See also
Direct product of binary relations
Examples of partia
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https://en.wikipedia.org/wiki/Stephanie%20Pace%20Marshall
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Stephanie Anne Pace Marshall (born July 19, 1945), is an American educator and the founding president of the Illinois Mathematics and Science Academy.
Education
Stephanie Anne Pace was born to Dominick Martin and Anne (née Price) Pace in the Bronx, New York on July 19, 1945, and grew up in the New York city area. She graduated from East Meadow High School in 1963. Pace attended Muhlenberg College from 1963 to 1965 before transferring to Queens College, City University of New York where she completed a B.A. in education and sociology in 1967. In 1971, she earned an M.A. in curriculum philosophy from the University of Chicago. In January 1983, she completed a Ph.D. in Educational Administration and Industrial Relations from Loyola University Chicago. Her dissertation was titled, An analysis of the profile, roles, functions, and behavior of women on boards of education in DuPage County, Illinois. Marshall's doctoral advisor was Melvin P. Heller.
Career
Marshall was a schoolteacher in elementary and junior high schools in Alsip, Illinois. She taught graduate courses at the National Louis University. In 1976, Marshall became assistant superintended for instruction for Batavia Public School District 101. From 1983 to 1985, She served as Batavia's superintendent.
Marshall served as president of the Illinois Mathematics and Science Academy from its 1985 founding until 2007. She was president of the Association for Supervision and Curriculum Development (ASCD).
Her philosophy of
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https://en.wikipedia.org/wiki/Tom%20DeMarco
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Tom DeMarco (born August 20, 1940) is an American software engineer, author, and consultant on software engineering topics. He was an early developer of structured analysis in the 1970s.
Early life and education
Tom DeMarco was born in Hazleton, Pennsylvania. He received a BSEE degree in Electrical Engineering from Cornell University, a M.S. from Columbia University, and a diplôme from the University of Paris.
Career
DeMarco started working at Bell Telephone Laboratories in 1963, where he participated in ESS-1 project to develop the first large scale Electronic Switching System, which became installed in telephone offices all over the world. Later in the 1960s he started working for a French IT consulting firm, where he worked on the development of a conveyor system for the new merchandise mart at La Villette in Paris, and in the 1970s on the development of on-line banking systems in Sweden, Holland, France and New York.
In the 1970s DeMarco was one of the major figures in the development of structured analysis and structured design in software engineering. In January 1978 he published Structured Analysis and System Specification, a major milestone in the field.
In the 1980s with Tim Lister, Stephen McMenamin, John F. Palmer, James Robertson and Suzanne Robertson, he founded the consulting firm "The Atlantic Systems Guild" in New York.
The firm initially shared offices with the Dorset House Publishing owned by Wendy Eachan, Tim Lister's wife. Their company developed int
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https://en.wikipedia.org/wiki/Physics%20%28band%29
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Physics was an instrumental band from San Diego, California, established by John D. Goff and Denver Lucas in late 1993 after the breakup of Johnny Superbad & the Bulletcatchers.
History
Featuring a rotating cast of musicians from the San Diego experimental underground but mainly composed of Denver Lucas on drums, Jeff Coad on synthesizers, John Goff, Will Goff, Jason Soares, Rob Crow, Travis Nelson, Ryan Jencks on guitar and Matt Lorenz on visuals/projections. This early incarnation came to be known as the "Black Period". Mainly inspired by theories in quantum theory and Eastern Mysticism, Physics was musically influenced by Krautrock, minimalism, early Doom/Drone, and Electronic Kosmische, though were often associated with the Math Rock genre. After the untimely death of Denver Lucas in the mid-1990s, the Physics personnel underwent numerous changes until resulting in Cameron Jones on drums which was later known as the "Gray Period" then ultimately the "White Period".
After Physics dissolved in 2000, Jason Soares and Jeff Coad went on to form the more electronic-based Aspects Of Physics also with Matt Lorenz. Will and John Goff went on to form the electronic band SSI. Rob Crow started Pinback (co-led by Zach Smith from Three Mile Pilot).
In 2015, coinciding with the release of the documentary It's Gonna Blow!!! San Diego's Music Underground 1986–1996, Physics reformed for reunion shows in Portland, Oregon and Los Angeles
Discography
Black 7", (Dagon Productions), 19
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https://en.wikipedia.org/wiki/Strongly%20compact%20cardinal
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In set theory, a branch of mathematics, a strongly compact cardinal is a certain kind of large cardinal.
A cardinal κ is strongly compact if and only if every κ-complete filter can be extended to a κ-complete ultrafilter.
Strongly compact cardinals were originally defined in terms of infinitary logic, where logical operators are allowed to take infinitely many operands. The logic on a regular cardinal κ is defined by requiring the number of operands for each operator to be less than κ; then κ is strongly compact if its logic satisfies an analog of the compactness property of finitary logic.
Specifically, a statement which follows from some other collection of statements should also follow from some subcollection having cardinality less than κ.
The property of strong compactness may be weakened by only requiring this compactness property to hold when the original collection of statements has cardinality below a certain cardinal λ; we may then refer to λ-compactness. A cardinal is weakly compact if and only if it is κ-compact; this was the original definition of that concept.
Strong compactness implies measurability, and is implied by supercompactness. Given that the relevant cardinals exist, it is consistent with ZFC either that the first measurable cardinal is strongly compact, or that the first strongly compact cardinal is supercompact; these cannot both be true, however. A measurable limit of strongly compact cardinals is strongly compact, but the least such limit is no
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https://en.wikipedia.org/wiki/Mario%20Jeckle
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Mario Jeckle (25 August 1974 – 11 June 2004) was a German computer scientist.
From 1997 to 2003, Jeckle attended the University of Applied Sciences in Augsburg. In 1998, he received his computer science degree for his thesis "Prozeßkettenmodellierung am Beispiel der Gießwerkzeugentwicklung und prototypische Implementierung auf Basis des EDM/PDM – Systems Metaphase" (An example of process chain modelling in casting tool development and prototype implementation on basis of the EDM/PDM – Systems Metaphase). At Augsburg, he taught Java, Java Threads, XML and software engineering.
In 2003, Jeckle became a professor at the University of Applied Sciences in Furtwangen im Schwarzwald. He taught about XML, databases, software engineering and eBusiness.
Jeckle was also a W3C and OMG representative of DaimlerChrysler Research and developed technical standards for XML, UML 2.0, and others. At the beginning of 2004, he was a member of the Technical Architecture Group of the World Wide Web Consortium (W3C). Jeckle was also an author of books and a speaker at conferences and seminars (information groups).
Jeckle was a member of the International Red Cross. On 11 June 2004, he died while giving aid to others who had a car accident on a German highway. While helping, Jeckle and a second man were hit by another driver who lost control. Tim Berners-Lee, whom Jeckle had previously collaborated with, spoke on his death, "Mario's involvement in the World Wide Web Consortium is a symbol of coll
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https://en.wikipedia.org/wiki/Helmut%20Ringsdorf
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Helmut Ringsdorf (30 July 1929 – 20 March 2023) was a German polymer chemist. His work promoted cross-disciplinary discussions and collaborations in the field of polymer chemistry, biology, physics and medicine.
Ringsdorf's major research works deal with the self-assembly of polymers into functional aggregates, where 'the whole is more than the sum of its parts'. He is known for being the first to propose covalently bonding drugs to water-soluble polymers.
Personal life
Ringsdorf was born in Gießen, People's State of Hesse in 1929.
Ringsdorf died on 20 March 2023, at the age of 93.
Education
Ringsdorf took undergraduate studies in Chemistry, Politics and Geology at the universities at Frankfurt, Darmstadt and Freiburg.
In 1956, Ringsdorf wrote his master's thesis under Hermann Staudinger and, in 1958, wrote his doctoral dissertation under Staudinger and . He was Staudinger's last student.
Postgraduate work
1960, Research Associate, Polytechnic Institute of Brooklyn, Brooklyn/United States, Polymer Science.
1959, Teaching Assistant, University of Freiburg, Germany, Polymer Chemistry.
Appointments/Affiliations
2001–2005 Adjunct Professor of Pharmacy, Cardiff University, Cardiff/Wales, United Kingdom
1995–2000 Courtauld Visiting Professor, University of California, Los Angeles United States
1994–2000 Adjunct Professor of Pharmacy, University of London, London, United Kingdom
1988–2003 Adjunct Professor of Poly. Sci., Jilin University, Changchun, People's Repub
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https://en.wikipedia.org/wiki/Subject-matter%20expert
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A subject-matter expert (SME) is a person who has accumulated great knowledge in a particular field or topic and this level of knowledge is demonstrated by the person's degree, licensure, and/or through years of professional experience with the subject, i.e. a PhD in chemistry could be easily declared as a SME in chemistry, or a person with a Second Class Radiotelegraph License or equivalent issued by the national licensing body (Federal Communications Commission in the United States, Ofcom in the UK, and National Telecommunications Commission in the Philippines, and other authorities around the world) could be considered a SME in radiotelegraphy. A person with a master's degree in electronic engineering could be considered a subject-matter expert in electronics, or a person with many years of experience in machining could be considered a SME in machining.
The term is used when developing materials about a topic (a book, an examination, a manual, etc.), and expertise on the topic is needed by the personnel developing the material. For example, tests are often created by a team of psychometricians and a team of SMEs. The psychometricians understand how to engineer a test while the SMEs understand the actual content of the exam. Books, manuals, and technical documentation are developed by technical writers and instructional designers in conjunctions with SMEs. Technical communicators interview SMEs to extract information and convert it into a form suitable for the audience. S
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https://en.wikipedia.org/wiki/Channeling
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Channeling, or channelling, may refer to:
Science
Channelling (physics), the process that constrains the path of a charged particle in a crystalline solid
Metabolite or substrate channeling in biochemistry and cell physiology
Other
Legal channeling, a contractual or legal redirection of responsibilities from an organization to another
Mediumship, influences attributed to esoteric communications via a person described as a medium or channel
Chopping and channeling of an automobile's body
See also
Channel (disambiguation)
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https://en.wikipedia.org/wiki/Gotthilf%20Hempel
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Gotthilf Hempel (born March 8, 1929) is a German marine biologist and oceanographer.
Live
Hempel studied biology and geology at the universities of Mainz and Heidelberg. In 1952 he gained his Ph.D. with a study on the energetics of grasshopper jumps from Heidelberg University. He then went on to work as a scientific assistant at various research institutes in Wilhelmshaven, Heligoland, and Hamburg, where he habilitated with a thesis on the ecology of fry in 1963.
In 1967 he became a professor at the University of Kiel at the Institute of Marine Sciences (Institut für Meereskunde Kiel), where he remained director of the Department of Fisheries Biology for the next 14 years and served as Acting Director of the institute from 1972 to 1976.
In 1981, he helped found the Alfred Wegener Institute for Polar and Marine Research in Bremerhaven whereupon he became the institution's first director. In the same year, he also became director of the Institute for Polar Ecology at the University of Kiel. In Bremerhaven, he initiated the construction of the polar research vessel PFS Polarstern. In 1992, he became the first director of the then newly founded Center for Marine Tropical Ecology at this time part of University of Bremen. Hempel retired in 1994.
He has been interested and active in research politics throughout his career. From 1963 to 1967 he worked for UNESCO and the FAO and from 1990 to 1996 he was a member of the Wissenschaftsrat, the scientific advisory committee of Ger
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https://en.wikipedia.org/wiki/Organosulfur%20chemistry
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Organosulfur chemistry is the study of the properties and synthesis of organosulfur compounds, which are organic compounds that contain sulfur. They are often associated with foul odors, but many of the sweetest compounds known are organosulfur derivatives, e.g., saccharin. Nature is abound with organosulfur compounds—sulfur is vital for life. Of the 20 common amino acids, two (cysteine and methionine) are organosulfur compounds, and the antibiotics penicillin and sulfa drugs both contain sulfur. While sulfur-containing antibiotics save many lives, sulfur mustard is a deadly chemical warfare agent. Fossil fuels, coal, petroleum, and natural gas, which are derived from ancient organisms, necessarily contain organosulfur compounds, the removal of which is a major focus of oil refineries.
Sulfur shares the chalcogen group with oxygen, selenium, and tellurium, and it is expected that organosulfur compounds have similarities with carbon–oxygen, carbon–selenium, and carbon–tellurium compounds.
A classical chemical test for the detection of sulfur compounds is the Carius halogen method.
Classes
Organosulfur compounds can be classified according to the sulfur-containing functional groups, which are listed (approximately) in decreasing order of their occurrence.
Sulfides
Sulfides, formerly known as thioethers, are characterized by C−S−C bonds Relative to C−C bonds, C−S bonds are both longer, because sulfur atoms are larger than carbon atoms, and about 10% weaker. Representative b
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https://en.wikipedia.org/wiki/Metabelian%20group
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In mathematics, a metabelian group is a group whose commutator subgroup is abelian. Equivalently, a group G is metabelian if and only if there is an abelian normal subgroup A such that the quotient group G/A is abelian.
Subgroups of metabelian groups are metabelian, as are images of metabelian groups over group homomorphisms.
Metabelian groups are solvable. In fact, they are precisely the solvable groups of derived length at most 2.
Examples
Any dihedral group is metabelian, as it has a cyclic normal subgroup of index 2. More generally, any generalized dihedral group is metabelian, as it has an abelian normal subgroup of index 2.
If F is a field, the group of affine maps (where a ≠ 0) acting on F is metabelian. Here the abelian normal subgroup is the group of pure translations , and the abelian quotient group is isomorphic to the group of homotheties . If F is a finite field with q elements, this metabelian group is of order q(q − 1).
The group of direct isometries of the Euclidean plane is metabelian. This is similar to the above example, as the elements are again affine maps. The translations of the plane form an abelian normal subgroup of the group, and the corresponding quotient is the circle group.
The finite Heisenberg group H3,p of order p3 is metabelian. The same is true for any Heisenberg group defined over a ring (group of upper-triangular 3 × 3 matrices with entries in a commutative ring).
All nilpotent groups of class 3 or less are metabelian.
The lamp
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https://en.wikipedia.org/wiki/Gavriil%20Adrianovich%20Tikhov
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Gavriil Adrianovich Tikhov (, 1 May 1875 – 25 January 1960) was a Soviet astronomer who was a pioneer in astrobiology and is considered to be the father of astrobotany. He worked as an observer at the Pulkovo Observatory from 1906 until 1941. After undertaking an expedition to Alma-Ata to observe the solar eclipse of September 21, 1941, he remained and became one of the founders of the Kamenskoe Plateau Observatory, the Fesenkov Astrophysical Institute, and the Kazakhstan Academy of Sciences.
G. A. Tikhov was born in Smolevichy, near Minsk, in the family of a railway employee, the family often moved from place to place. He began to study at the gymnasium of Pavlodar, and completed secondary education at the Simferopol gymnasium. Living in Simferopol, he once saw two bright stars in the clear evening sky. He learned from the teacher of the Simferopol gymnasium that these stars are the planet Venus and the star Sirius. At the Simferopol Public Library, he read two astronomical books. "I read these books with exciting interest, and my fate was decided. In the spring of 1892 I will never forget - then I irrevocably decided to become an astronomer," he writes in his memoir, 60 Years Near the Telescope. At the gymnasium observatory, he first looked through a telescope.
Tikhov invented the feathering spectrograph by using the commonly occurring chromatic aberration to his advantage. By installing a ring-shaped diaphragm in front of the objective he enabled an observer to deduce th
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https://en.wikipedia.org/wiki/Weinberg%20angle
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The weak mixing angle or Weinberg angle is a parameter in the Weinberg–Salam theory of the electroweak interaction, part of the Standard Model of particle physics, and is usually denoted as . It is the angle by which spontaneous symmetry breaking rotates the original and vector boson plane, producing as a result the boson, and the photon. Its measured value is slightly below 30°, but also varies, very slightly increasing, depending on how high the relative momentum of the particles involved in the interaction is that the angle is used for.
Details
The algebraic formula for the combination of the and vector bosons (i.e. 'mixing') that simultaneously produces the massive boson and the massless photon () is expressed by the formula
The weak mixing angle also gives the relationship between the masses of the W and Z bosons (denoted as and ),
The angle can be expressed in terms of the and couplings (weak isospin and weak hypercharge , respectively),
and
The electric charge is then expressible in terms of it, (refer to the figure).
Because the value of the mixing angle is currently determined empirically, in the absence of any superseding theoretical derivation it is mathematically defined as
The value of varies as a function of the momentum transfer, , at which it is measured. This variation, or 'running', is a key prediction of the electroweak theory. The most precise measurements have been carried out in electron–positron collider experiments at a value of , c
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https://en.wikipedia.org/wiki/JILA
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JILA, formerly known as the Joint Institute for Laboratory Astrophysics, is a physical science research institute in the United States. JILA is located on the University of Colorado Boulder campus. JILA was founded in 1962 as a joint institute of The University of Colorado Boulder and the National Institute of Standards & Technology.
Research
JILA is one of the nation’s leading research institutes in the physical sciences. The world's first Bose-Einstein Condensate was created at JILA by Eric Cornell and Carl Wieman in 1995. The first frequency comb demonstration was led by John L. Hall at JILA. The first demonstrations of a Fermionic condensate and BEC-BCS crossover physics were done by Deborah S. Jin.
JILA's members hold faculty appointments in the Departments of Physics; Astrophysical and Planetary Science; Chemistry and Biochemistry; and Molecular, Cellular, and Developmental Biology as well as Engineering. JILA’s Quantum Physics Division of NIST members hold joint faculty appointments at CU in the same departments.
Research at JILA addresses fundamental scientific questions about the limits of quantum measurements and technologies, the design of precision optical and X-ray lasers, the fundamental principles underlying the interaction of light and matter, the role of quantum physics in chemistry and biology, and the processes that have governed the evolution of the Universe for nearly 14 billion years.
Staff
JILA's current faculty includes two Nobel laureates—Eric C
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https://en.wikipedia.org/wiki/Drew%20Endy
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Andrew (Drew) David Endy (born 1970) is a synthetic biologist and tenured associate professor of bioengineering at Stanford University, California.
Education and Work History
Endy received his PhD from Dartmouth College in 1997 for his work on genetic engineering using T7 phage.
Endy was a junior fellow for 3 years and later an Assistant Professor of Biological Engineering at MIT (2002–2008). In 2008, Endy moved to Stanford University, where he currently serves as an Associate Professor of Bioengineering.
Research
With Thomas Knight, Gerald Jay Sussman, Randy Rettberg, and others at MIT, Endy worked on synthetic biology and the engineering of standardized biological components, devices, and parts, collectively known as BioBricks. Endy is one of several founders of the Registry of Standard Biological Parts, and invented an abstraction hierarchy for integrated genetic systems.
Endy has been one of the early promoters of open source biology, and helped start the Biobricks Foundation, a not-for-profit organization that will work to support open-source biology. He was also a co-founder of the now defunct Codon Devices, a biotechnology startup company that aimed to commercialize synthetic biology.
In 2009, Michael Specter called Endy "synthetic biology’s most compelling evangelist" in his book Denialism: How Irrational Thinking Hinders Scientific Progress, Harms the Planet, and Threatens Our Lives, as Endy is persistent in discussing both the prospects and dangers of synthetic
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https://en.wikipedia.org/wiki/Calixarene
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A calixarene is a macrocycle or cyclic oligomer based on a methylene-linked phenols. With hydrophobic cavities that can hold smaller molecules or ions, calixarenes belong to the class of cavitands known in host–guest chemistry.
Nomenclature
Calixarene nomenclature is straightforward and involves counting the number of repeating units in the ring and including it in the name. A calix[4]arene has 4 units in the ring and a calix[6]arene has 6. A substituent in the meso position Rb is added to the name with a prefix C- as in C-methylcalix[6]arene The word calixarene is derived from the Greek calix or chalice because this type of molecule resembles a vase (or cup) and from the word arene that refers to the aromatic building block.
Synthesis
Calixarenes are generally produced by condensation of two components: an electron-rich aromatic compound, classically a 4-substituted phenol, and an aldehyde, classically formaldehyde.
The scope for the aromatic component is broad diverse. The key attribute is susceptibility toward hydroxyalkylation. The related resorcinarenes and pyrogallolarenes are produced from resorcinol and pyrogallol, respectively.
The aldehyde most often used is formaldehyde, while larger aldehydes, like acetaldehyde, are usually required in condensation reactions with resorcinol and pyrogallol to facilitate formation of the C4v symmetric vase conformation. Additionally, substituted aldehydes and some heterocycles (e.g. furan) may be used to impart additional fun
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https://en.wikipedia.org/wiki/Geobiology
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Geobiology is a field of scientific research that explores the interactions between the physical Earth and the biosphere. It is a relatively young field, and its borders are fluid. There is considerable overlap with the fields of ecology, evolutionary biology, microbiology, paleontology, and particularly soil science and biogeochemistry. Geobiology applies the principles and methods of biology, geology, and soil science to the study of the ancient history of the co-evolution of life and Earth as well as the role of life in the modern world. Geobiologic studies tend to be focused on microorganisms, and on the role that life plays in altering the chemical and physical environment of the pedosphere, which exists at the intersection of the lithosphere, atmosphere, hydrosphere and/or cryosphere. It differs from biogeochemistry in that the focus is on processes and organisms over space and time rather than on global chemical cycles.
Geobiological research synthesizes the geologic record with modern biologic studies. It deals with process - how organisms affect the Earth and vice versa - as well as history - how the Earth and life have changed together. Much research is grounded in the search for fundamental understanding, but geobiology can also be applied, as in the case of microbes that clean up oil spills.
Geobiology employs molecular biology, environmental microbiology, organic geochemistry, and the geologic record to investigate the evolutionary interconnectedness of life an
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https://en.wikipedia.org/wiki/Hiyama%20coupling
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The Hiyama coupling is a palladium-catalyzed cross-coupling reaction of organosilanes with organic halides used in organic chemistry to form carbon–carbon bonds (C-C bonds). This reaction was discovered in 1988 by Tamejiro Hiyama and Yasuo Hatanaka as a method to form carbon-carbon bonds synthetically with chemo- and regioselectivity. The Hiyama coupling has been applied to the synthesis of various natural products.
R: aryl, alkenyl or alkynyl
R': aryl, alkenyl, alkynyl or alkyl
R'': Cl, F or alkyl
X: Cl, Br, I or OTf
Reaction history
The Hiyama coupling was developed to combat the issues associated with other organometallic reagents. The initial reactivity of organosilicon was not actually first reported by Hiyama, as Kumada reported a coupling reaction using organofluorosilicates shown below. Organosilanes were then discovered, by Hiyama, to have reactivity when activated by a fluoride source. This reactivity, when combined with a palladium salt, creates a carbon-carbon bond with an electrophillic carbon, like an organic halide. Compared to the inherent issues of well-used organometalics reagents, such as organomagnesium (Grignard reagents) and organocopper reagents, which are very reactive and are known to have low chemoselectivity, enough to destroy functional groups on both coupling partners, organosilicon compounds are inactive. Other organometallic reagents using metals such as zinc, tin, and boron, reduce the reactivity issue, but have other problems associated
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https://en.wikipedia.org/wiki/Two-photon%20physics
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Two-photon physics, also called gamma–gamma physics, is a branch of particle physics that describes the interactions between two photons. Normally, beams of light pass through each other unperturbed. Inside an optical material, and if the intensity of the beams is high enough, the beams may affect each other through a variety of non-linear effects. In pure vacuum, some weak scattering of light by light exists as well. Also, above some threshold of this center-of-mass energy of the system of the two photons, matter can be created.
Astronomy
Cosmological/intergalactic gamma rays
Photon–photon interactions limit the spectrum of observed gamma-ray photons at moderate cosmological distances to a photon energy below around 20 GeV, that is, to a wavelength of greater than approximately . This limit reaches up to around 20 TeV at merely intergalactic distances.
An analogy would be light traveling through a fog: At near distances a light source is more clearly visible than can at long distances due to the scattering of light by fog particles. Similarly, the further a gamma-ray travels through the universe, the more likely it is to be scattered by an interaction with a low energy photon from the extragalactic background light.
At those energies and distances, very high energy gamma-ray photons have a significant probability of a photon-photon interaction with a low energy background photon from the extragalactic background light resulting in either the creation of particle-antipart
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https://en.wikipedia.org/wiki/Hugh%20Clapperton
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Bain Hugh Clapperton (18 May 1788 – 13 April 1827) was a Scottish naval officer and explorer of West and Central Africa.
Early career
Clapperton was born in Annan, Dumfriesshire, where his father, George Clapperton, was a surgeon. He gained some knowledge of practical mathematics and navigation, and at thirteen was apprenticed on board a vessel which traded between Liverpool and North America. After having made several voyages across the Atlantic Ocean, he was impressed for the navy, in which he soon rose to the rank of midshipman. During the Napoleonic Wars he saw a good deal of active service, and at the storming of Port Louis, Mauritius, in November 1810, he was first in the breach and hauled down the French flag.
In 1814 Clapperton went to Canada, was promoted to the rank of lieutenant, and to the command of a schooner on the Canadian lakes. In 1817, when the flotilla on the lakes was dismantled, he returned home on half-pay. In 1820 Clapperton removed to Edinburgh, where he made the acquaintance of Walter Oudney, who aroused his interest in African travel.
African exploration
Lieutenant G. F. Lyon having returned from an unsuccessful attempt to reach Bornu from Tripoli, the British government determined on a second expedition to that country. Walter Oudney was appointed by Lord Bathurst, then colonial secretary, to proceed to Bornu as consul, accompanied by Hugh Clapperton. From Tripoli, early in 1822, they set out southward to Murzuk, where they were later joined by
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https://en.wikipedia.org/wiki/Churchill%20Scholarship
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The Churchill Scholarship is awarded by the Winston Churchill Foundation of the United States to graduates of the more than one hundred colleges and universities invited to participate in the Churchill Scholarship Program, for the pursuit of research and study in the physical and natural sciences, mathematics, engineering, for one year at Churchill College at the University of Cambridge.
The scholarship is often considered one of the most prestigious and competitive international fellowships available to American graduate students, alongside the Marshall, Rhodes, Gates Cambridge, Fulbright, and Mitchell scholarships. Each year, up to two students may be endorsed by each of the 110 U.S. institutions invited to participate in the program.
History
In 1958, Churchill College at Cambridge was founded in honor of Sir Winston Churchill with a primary focus on science, engineering and mathematics. Anticipating the final establishment of the college, Churchill met with American friends Lewis W. Douglas, John Loeb Sr., and Carl Gilbert to ask them to create a scholarship for young Americans to study at the college. In 1959, the Winston Churchill Foundation of the United States was established as a nonprofit charitable organization. The Foundation initially made travel grants to Churchill Overseas Fellows, distinguished senior faculty from American colleges and universities who would spend a sabbatical year at the College. Eight of the Churchill Fellows won the Nobel Prize.
In 196
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https://en.wikipedia.org/wiki/National%20Aquarium
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There are several institutions known as the National Aquarium:
Africa
National Marine Aquarium of Namibia
Asia
National Museum of Marine Biology and Aquarium, Taiwan
Europe
National Aquarium Denmark
National Marine Aquarium, Plymouth, England
North America
National Aquarium (Baltimore), U.S.
National Aquarium (Washington, D.C.), U.S.
Oceania
National Aquarium of New Zealand
National Zoo & Aquarium, Canberra, Australia
Lists of aquaria
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https://en.wikipedia.org/wiki/Boris%20Babayan
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Boris Artashesovich Babayan (; ; born Baku, 20 December 1933) is a Soviet and Russian computer scientist of Armenian descent, notable as the pioneering creator of supercomputers in the former Soviet Union and Russia.
Biography
Babayan was born in Baku, Soviet Union to an Armenian family. He graduated from the Moscow Institute of Physics and Technology in 1957. He completed his Ph.D. in 1964 and his doctorate of science in 1971.
From 1956 to 1996, Babayan worked in the Lebedev Institute of Precision Mechanics and Computer Engineering, where he eventually became chief of the hardware and software division. Babayan and his team built their first computers during the 1950s. In the 1970s, being one of 15 deputies of chief architect V. S. Burtsev, he worked on the first superscalar computer, the Elbrus-1 and programming language Эль-76. Using these computers in 1978, ten years before commercial applications appeared in the West, the Soviet Union developed its missile systems and its nuclear and space programs.
A team headed by Babayan designed Elbrus-3 computer using an architecture named Explicitly Parallel Instruction Computing (EPIC).
From 1992 to 2004, Babayan held senior positions in the Moscow Center for SPARC Technology (MCST) and Elbrus International. In these roles he led the development of Elbrus 2000 (single-chip implementation of Elbrus-3) and Elbrus90micro (SPARC computer based on domestically developed microprocessor) projects.
Since August 2004, Babayan is the
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https://en.wikipedia.org/wiki/Viktor%20Kaplan
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Viktor Kaplan (27 November 1876 – 23 August 1934) was an Austrian engineer and the inventor of the Kaplan turbine.
Life
Kaplan was born in Mürzzuschlag, Austria into a railroad worker's family. He graduated from high school in Vienna in 1895, after which he attended the Technical University of Vienna, where he studied mechanical engineering and specialised in diesel engines. From 1900 to 1901 he was drafted into military service in Pula.
After working in Vienna with a specialisation in motors, he moved to the German Technical University in Brno to conduct research at the institute of civil engineering. He spent the next three decades of his life in Brno, and nearly all his inventions and research are connected with his professorship there. In 1913 he was appointed head of the institute for water turbines.
In 1912 he published his most notable work: the Kaplan turbine, a revolutionary water turbine that was especially fitted to produce electricity from large streams with only a moderate incline. From 1912 to 1913 he received four patents on these kinds of turbines.
In 1918 the first Kaplan turbine with 26 kW power and a diameter of 60 cm was built by the Storek construction company for a textile manufacturer in Lower Austria. This turbine was used until 1955 and today is exhibited at the Technisches Museum Wien. After the success of the first Kaplan turbines they started being used worldwide and remain one of the most widely used kinds of water turbines.
In 1926 and 1934
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https://en.wikipedia.org/wiki/Jahn%E2%80%93Teller%20effect
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The Jahn–Teller effect (JT effect or JTE) is an important mechanism of spontaneous symmetry breaking in molecular and solid-state systems which has far-reaching consequences in different fields, and is responsible for a variety of phenomena in spectroscopy, stereochemistry, crystal chemistry, molecular and solid-state physics, and materials science. The effect is named for Hermann Arthur Jahn and Edward Teller, who first reported studies about it in 1937.
Simplified overview
The Jahn–Teller effect, sometimes also referred to as Jahn–Teller distortion, describes the geometrical distortion of molecules and ions that results from certain electron configurations. The Jahn–Teller theorem essentially states that any non-linear molecule with a spatially degenerate electronic ground state will undergo a geometrical distortion that removes that degeneracy, because the distortion lowers the overall energy of the species. For a description of another type of geometrical distortion that occurs in crystals with substitutional impurities see article off-center ions.
Transition metal chemistry
The Jahn–Teller effect is most often encountered in octahedral complexes of the transition metals. The phenomenon is very common in six-coordinate copper(II) complexes. The d9 electronic configuration of this ion gives three electrons in the two degenerate eg orbitals, leading to a doubly degenerate electronic ground state. Such complexes distort along one of the molecular fourfold axes (always la
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https://en.wikipedia.org/wiki/149%20%28number%29
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149 (one hundred [and] forty-nine) is the natural number between 148 and 150.
In mathematics
149 is a prime number, the first prime whose difference from the previous prime is exactly 10, an emirp, and an irregular prime. After 1 and 127, it is the third smallest de Polignac number, an odd number that cannot be represented as a prime plus a power of two. More strongly, after 1, it is the second smallest number that is not a sum of two prime powers.
It is a tribonacci number, being the sum of the three preceding terms, 24, 44, 81.
There are exactly 149 integer points in a closed circular disk of radius 7, and exactly 149 ways of placing six queens (the maximum possible) on a 5 × 5 chess board so that each queen attacks exactly one other. The barycentric subdivision of a tetrahedron produces an abstract simplicial complex with exactly 149 simplices.
See also
The year AD 149 or 149 BC
List of highways numbered 149
References
External links
Integers
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https://en.wikipedia.org/wiki/SNH
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SNH may refer to:
Scottish Natural Heritage
Stanthorpe Airport, IATA airport code "SNH"
Organotin hydrides R4−nSnHn in organotin chemistry
SNH48
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https://en.wikipedia.org/wiki/Franklin%20College%20%28Indiana%29
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Franklin College is a private liberal arts college in Franklin, Indiana. It was founded in 1834 and has a wooded campus spanning including athletic fields and a biology woodland. The college offers its approximately 1,000 students Bachelor of Arts degrees in 49 majors from 25 academic disciplines, 43 minors, 11 pre-professional programs, and five cooperative programs. The college also offers a Master of Science in Athletic Training and a Master of Science in Physician Assistant Studies. In 1842, the college began admitting women, becoming the first coeducational institution in Indiana and the seventh in the nation. Franklin College has historically maintained an affiliation with the American Baptist Churches USA.
History
Franklin College was originally founded in 1834 as the Indiana Baptist Manual-Labor Institute, a manual labor college. Ten years later, the Indiana General Assembly changed the school's name to Franklin College.
Academics
The school offers major topics of study, including biology, chemistry, journalism, art, political science, theatre, and music. There are 49 majors from 25 academic disciplines, 43 minors, 11 pre-professional programs, two master's programs, and five cooperative programs. Individualized majors and minors are also available.
Franklin College places a large emphasis on the liberal arts and sciences curriculum, requiring students to reorient themselves with standard mathematics, world history, literature, English, and speech skills as we
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https://en.wikipedia.org/wiki/Isotropic%20manifold
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In mathematics, an isotropic manifold is a manifold in which the geometry does not depend on directions. Formally, we say that a Riemannian manifold is isotropic if for any point and unit vectors , there is an isometry of with and . Every connected isotropic manifold is homogeneous, i.e. for any there is an isometry of with This can be seen by considering a geodesic from to and taking the isometry which fixes and maps to
Examples
The simply-connected space forms (the n-sphere, hyperbolic space, and ) are isotropic. It is not true in general that any constant curvature manifold is isotropic; for example, the flat torus is not isotropic. This can be seen by noting that any isometry of which fixes a point must lift to an isometry of which fixes a point and preserves ; thus the group of isometries of which fix is discrete. Moreover, it can be seen in a same way that no oriented surface with constant curvature and negative Euler characteristic is isotropic.
Moreover, there are isotropic manifolds which do not have constant curvature, such as the complex projective space () equipped with the Fubini-Study metric. Indeed, the universal cover of any constant-curvature manifold is either a sphere, or a hyperbolic space, or . But is simply-connected yet not a sphere (for ), as can be seen for example from homotopy group calculations from long exact sequence of the fibration .
Further examples of isotropic manifolds are given by the rank one symmetric spaces, inc
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https://en.wikipedia.org/wiki/Christer%20Fuglesang
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Arne Christer Fuglesang (born 18 March 1957) is a Swedish physicist and an ESA astronaut. He was first launched aboard the STS-116 Space Shuttle mission on 10 December 2006, making him the first Swedish citizen in space.
Married with three children, he was a Fellow at CERN and taught mathematics at the Royal Institute of Technology before being selected to join the European Astronaut Corps in 1992. He has participated in two Space Shuttle missions and five spacewalks, and is the first person outside of the United States or Russian space programs to participate in more than three spacewalks.
Early life and education
Fuglesang was born in Stockholm to a Swedish mother and a Norwegian father, who became a Swedish citizen shortly before Fuglesang's birth. Fuglesang graduated from the Bromma Gymnasium, Stockholm in 1975, earned a master's degree in engineering physics from the Royal Institute of Technology (KTH), in Stockholm in 1981, and received a doctorate in experimental particle physics from Stockholm University in 1987. He became an associate professor (docent) of particle physics at Stockholm University in 1991.
He married Elisabeth (Lisa) Fuglesang (née Walldie) in 1983, whom he met at the Royal Institute of Technology (KTH). They have three children.
Fuglesang is a prominent member of the Swedish skeptics association Vetenskap och Folkbildning and identifies strongly with skeptics and atheists.
In 2012, Fuglesang received the Royal Institute of Technology 2012 Alumn
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https://en.wikipedia.org/wiki/Donald%20Gillies
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Donald Gillies may refer to:
Donald B. Gillies (1928–1975), mathematician and computer scientist
Donald A. Gillies (born 1944), historian of mathematics
Donnie Gillies (born 1951), Scottish footballer
See also
Donald Gillis (disambiguation)
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https://en.wikipedia.org/wiki/ID3%20algorithm
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In decision tree learning, ID3 (Iterative Dichotomiser 3) is an algorithm invented by Ross Quinlan used to generate a decision tree from a dataset. ID3 is the precursor to the C4.5 algorithm, and is typically used in the machine learning and natural language processing domain
Algorithm
The ID3 algorithm begins with the original set as the root node. On each iteration of the algorithm, it iterates through every unused attribute of the set and calculates the entropy or the information gain of that attribute. It then selects the attribute which has the smallest entropy (or largest information gain) value. The set is then split or partitioned by the selected attribute to produce subsets of the data. (For example, a node can be split into child nodes based upon the subsets of the population whose ages are less than 50, between 50 and 100, and greater than 100.) The algorithm continues to recurse on each subset, considering only attributes never selected before.
Recursion on a subset may stop in one of these cases:
every element in the subset belongs to the same class; in which case the node is turned into a leaf node and labelled with the class of the examples.
there are no more attributes to be selected, but the examples still do not belong to the same class. In this case, the node is made a leaf node and labelled with the most common class of the examples in the subset.
there are no examples in the subset, which happens when no example in the parent set was found to m
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https://en.wikipedia.org/wiki/C4.5%20algorithm
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C4.5 is an algorithm used to generate a decision tree developed by Ross Quinlan. C4.5 is an extension of Quinlan's earlier ID3 algorithm. The decision trees generated by C4.5 can be used for classification, and for this reason, C4.5 is often referred to as a statistical classifier. In 2011, authors of the Weka machine learning software described the C4.5 algorithm as "a landmark decision tree program that is probably the machine learning workhorse most widely used in practice to date".
It became quite popular after ranking #1 in the Top 10 Algorithms in Data Mining pre-eminent paper published by Springer LNCS in 2008.
Algorithm
C4.5 builds decision trees from a set of training data in the same way as ID3, using the concept of information entropy. The training data is a set of already classified samples. Each sample consists of a p-dimensional vector , where the represent attribute values or features of the sample, as well as the class in which falls.
At each node of the tree, C4.5 chooses the attribute of the data that most effectively splits its set of samples into subsets enriched in one class or the other. The splitting criterion is the normalized information gain (difference in entropy). The attribute with the highest normalized information gain is chosen to make the decision. The C4.5 algorithm then recurses on the partitioned sublists.
This algorithm has a few base cases.
All the samples in the list belong to the same class. When this happens, it simply crea
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https://en.wikipedia.org/wiki/Siegel%20zero
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In mathematics, more specifically in the field of analytic number theory, a Landau–Siegel zero or simply Siegel zero (also known as exceptional zero), named after Edmund Landau and Carl Ludwig Siegel, is a type of potential counterexample to the generalized Riemann hypothesis, on the zeros of Dirichlet L-functions associated to quadratic number fields. Roughly speaking, these are possible zeros very near (in a quantifiable sense) to .
Motivation and definition
The way in which Siegel zeros appear in the theory of Dirichlet L-functions is as potential exceptions to the classical zero-free regions, which can only occur when the L-function is associated to a real Dirichlet character.
Real primitive Dirichlet characters
For an integer , a Dirichlet character modulo is an arithmetic function satisfying the following properties:
(Completely multiplicative) for every , ;
(Periodic) for every ;
(Support) if .
That is, is the lifting of a homomorphism .
The trivial character is the character modulo 1, and the principal character modulo , denoted , is the lifting of the trivial homomorphism .
A character is called imprimitive if there exists some integer with such that the induced homomorphism factors as
for some character ; otherwise, is called primitive.
A character is real (or quadratic) if it equals its complex conjugate (defined as ), or equivalently if . The real primitive Dirichlet characters are in one-to-one correspondence with the Kronecker symbols fo
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https://en.wikipedia.org/wiki/Distribution
|
Distribution may refer to:
Mathematics
Distribution (mathematics), generalized functions used to formulate solutions of partial differential equations
Probability distribution, the probability of a particular value or value range of a variable
Cumulative distribution function, in which the probability of being no greater than a particular value is a function of that value
Frequency distribution, a list of the values recorded in a sample
Inner distribution, and outer distribution, in coding theory
Distribution (differential geometry), a subset of the tangent bundle of a manifold
Distributed parameter system, systems that have an infinite-dimensional state-space
Distribution of terms, a situation in which all members of a category are accounted for
Distributivity, a property of binary operations that generalises the distributive law from elementary algebra
Distribution (number theory)
Distribution problems, a common type of problems in combinatorics where the goal is to enumerate the number of possible distributions of objects to recipients, subject to various conditions; see Twelvefold way
Computing and telecommunications
Distribution (concurrency), the projection operator in a history monoid, a representation of the histories of concurrent computer processes
Data distribution or dissemination, to distribute information without direct feedback
Digital distribution, publishing media digitally
Distributed computing, the coordinated use of physically distributed computers (
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https://en.wikipedia.org/wiki/Thermal%20expansion%20coefficients%20of%20the%20elements%20%28data%20page%29
|
Thermal expansion
Notes
All values refer to 25 °C unless noted.
References
CRC
As quoted from this source in an online version of: David R. Lide (ed), CRC Handbook of Chemistry and Physics, 84th Edition. CRC Press. Boca Raton, Florida, 2003; Section 12, Properties of Solids; Thermal and Physical Properties of Pure Metals
Touloukian, Y. S., Thermophysical Properties of Matter, Vol. 12, Thermal Expansion, IFI/Plenum, New York, 1975.
CR2
As quoted in an online version of:
David R. Lide (ed), CRC Handbook of Chemistry and Physics, 84th Edition. CRC Press. Boca Raton, Florida, 2003; Section 4, Properties of the Elements and Inorganic Compounds; Physical Properties of the Rare Earth Metals
which further refers to:
Beaudry, B. J. and Gschneidner, K.A., Jr., in Handbook on the Physics and Chemistry of Rare Earths, Vol. 1, Gschneidner, K.A., Jr. and Eyring, L., Eds., North-Holland Physics, Amsterdam, 1978, 173.
McEwen, K.A., in Handbook on the Physics and Chemistry of Rare Earths, Vol. 1, Gschneidner, K.A., Jr. and Eyring, L., Eds., North-Holland Physics, Amsterdam, 1978, 411.
LNG
As quoted from this source in an online version of: J.A. Dean (ed), Lange's Handbook of Chemistry (15th Edition), McGraw-Hill, 1999; Section 4; Table 4.1, Electronic Configuration and Properties of the Elements
Touloukian, Y. S., Thermophysical Properties of Matter, Vol. 12, Thermal Expansion, Plenum, New York, 1975.
WEL
As quoted at http://www.webelements.com/ from these sources:
D.R. Lide, (
|
https://en.wikipedia.org/wiki/Hung-Chang%20Lin
|
Hung Chang Lin (Jimmy Lin) (; August 8, 1919 – March 5, 2009) was a Chinese-American inventor and a professor of Electrical Engineering at the University of Maryland.
Early life and education
Lin was born in Shanghai, China. He attended Shanghai Jiaotong University, China on a tennis scholarship. Lin graduated with B.S. in electrical engineering in 1941. In 1948 he received the M.S. degree in electrical engineering from the University of Michigan. In 1956 he received the Doctor of Electrical Engineering from the Polytechnic Institute of Brooklyn.
Career
After graduating from Shanghai Jiaotong University, Lin worked for the Central Radio Works and Central Broadcasting Administration as an engineer. He left China in 1947 to begin his graduate work.
After he earned his master's and doctorate degrees, Lin was worked at RCA Laboratories and was one of the first scientists to work on transistor circuit development. Lin was the first inventor to incorporate p-n-p or complementary integrated circuits. He later worked for CBS and Westinghouse Electric Corporation, researching and developing electrical engineering practices.
In 1969, Lin began teaching at the University of Maryland. He worked at the university until his retirement in 1990. While a professor, Lin supervised and mentored 26 PhD students. He also worked part-time as an adjunct and visiting professor at the University of Pittsburgh and University of California, Berkeley, respectively.
Hung C. Lin held more than 60 U
|
https://en.wikipedia.org/wiki/Richard%20O%27Keefe
|
Richard A. O'Keefe is a computer scientist best known for writing the influential 1990 book on Prolog programming, The Craft of Prolog. He was a lecturer and researcher at the department of computer science at the University of Otago in Dunedin, New Zealand and concentrates on programming languages for logic programming and functional programming, including Prolog, Haskell, and Erlang.
References
External links
, University of Otago
Programming language researchers
New Zealand computer scientists
Living people
Year of birth missing (living people)
Academic staff of the University of Otago
University of Otago alumni
|
https://en.wikipedia.org/wiki/Cartan%E2%80%93K%C3%A4hler%20theorem
|
In mathematics, the Cartan–Kähler theorem is a major result on the integrability conditions for differential systems, in the case of analytic functions, for differential ideals . It is named for Élie Cartan and Erich Kähler.
Meaning
It is not true that merely having contained in is sufficient for integrability. There is a problem caused by singular solutions. The theorem computes certain constants that must satisfy an inequality in order that there be a solution.
Statement
Let be a real analytic EDS. Assume that is a connected, -dimensional, real analytic, regular integral manifold of with (i.e., the tangent spaces are "extendable" to higher dimensional integral elements).
Moreover, assume there is a real analytic submanifold of codimension containing and such that has dimension for all .
Then there exists a (locally) unique connected, -dimensional, real analytic integral manifold of that satisfies .
Proof and assumptions
The Cauchy-Kovalevskaya theorem is used in the proof, so the analyticity is necessary.
References
Jean Dieudonné, Eléments d'analyse, vol. 4, (1977) Chapt. XVIII.13
R. Bryant, S. S. Chern, R. Gardner, H. Goldschmidt, P. Griffiths, Exterior Differential Systems, Springer Verlag, New York, 1991.
External links
R. Bryant, "Nine Lectures on Exterior Differential Systems", 1999
E. Cartan, "On the integration of systems of total differential equations," transl. by D. H. Delphenich
E. Kähler, "Introduction to the theory of systems of differ
|
https://en.wikipedia.org/wiki/Extended%20affix%20grammar
|
In computer science, extended affix grammars (EAGs) are a formal grammar formalism for describing the context free and context sensitive syntax of language, both natural language and programming languages.
EAGs are a member of the family of two-level grammars; more specifically, a restriction of Van Wijngaarden grammars with the specific purpose of making parsing feasible.
Like Van Wijngaarden grammars, EAGs have hyperrules that form a context-free grammar except in that their nonterminals may have arguments, known as affixes, the possible values of which are supplied by another context-free grammar, the metarules.
EAGs were introduced and studied by D.A. Watt in 1974; recognizers were developed at the University of Nijmegen between 1985 and 1995. The EAG compiler developed there will generate either a recogniser, a transducer, a translator, or a syntax directed editor for a language described in the EAG formalism. The formalism is quite similar to Prolog, to the extent that it borrowed its cut operator.
EAGs have been used to write grammars of natural languages such as English, Spanish, and Hungarian. The aim was to verify the grammars by making them parse corpora of text (corpus linguistics); hence, parsing had to be sufficiently practical. However, the parse tree explosion problem that ambiguities in natural language tend to produce in this type of approach is worsened for EAGs because each choice of affix value may produce a separate parse, even when several diffe
|
https://en.wikipedia.org/wiki/Masayori%20Inouye
|
Masayori Inouye is a distinguished professor in the department of biochemistry and molecular biology at the Robert Wood Johnson Medical School at Rutgers University. He, along with his team, discovered natural antisense RNA.
Inouye was also a key scientist involved in the discovery and characterization of retrons, which are retroviral-like elements found in various bacterial genomes.
In 2019, he was elected to the National Academy of Sciences.
Early life and career
Inouye was born in Port Arthur in Manchuria in 1934 and after the World War II, he went back to Japan. He studied at Osaka University, Japan and got his Ph.D. in 1963. After 5-years postdoctoral experience, he moved to Princeton University as a research associate working on the mechanism of cell division. 1970, he joined the faculty at State University of New York at Stony Brook. In 1987, he took a position as chair of the department of biochemistry at Robert Wood Johnson Medical School.
References
External links
Bio at Rutgers
Jennifer Viegas (PNAS): Profile of Masayori Inouye
Stony Brook University faculty
Living people
Year of birth missing (living people)
Members of the United States National Academy of Sciences
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https://en.wikipedia.org/wiki/Alan%20Grodzinsky
|
Alan J. Grodzinsky is an American scientist and Professor of Electrical, Mechanical and Biological Engineering and Director of the Center for Biomedical Engineering at MIT. He graduated in Electrical Engineering from MIT in 1971, obtaining a doctorate three years later under the supervision of James Melcher, with a thesis on membrane electromechanics.
Grodzinsky is widely recognized for his research investigating the mechanical, chemical and electrical properties of connective tissue, including studies on cartilage tissue engineering, with implications for understanding and curing diseases such as osteoarthritis. He has published over 315 peer reviewed papers which have been cited almost 30,000 times in Google Scholar. He has supervised 25 post-doctoral candidates, 52 Ph.D./Sc.D. students, 2 M.D. students, 52 M.S. students and 63 B.S students. He has been honored with the 2018 Orthopaedic Research Society Outstanding Achievement in Mentoring Award for his lifelong commitment to excellence in mentoring trainees both in his lab and around the world.
Grodzinsky was a founding Fellow of the American Institute of Medical and Biological Engineering in 1993. He has served as the President of the Bioelectrical Repair and Growth Society (1986–87), Chairman of the Gordon Research Conference on Musculoskeletal Biology & Bioengineering (1990), President of the International Cartilage Repair Society (1998-2000) and President of the Orthopaedic Research Society (2007–08). He received a N
|
https://en.wikipedia.org/wiki/Proportion%20%28architecture%29
|
Proportion is a central principle of architectural theory and an important connection between mathematics and art. It is the visual effect of the relationship of the various objects and spaces that make up a structure to one another and to the whole. These relationships are often governed by multiples of a standard unit of length known as a "module".
Proportion in architecture was discussed by Vitruvius, Leon Battista Alberti, Andrea Palladio, and Le Corbusier among others.
Roman architecture
Vitruvius
Architecture in Roman antiquity was rarely documented except in the writings of Vitruvius' treatise De architectura. Vitruvius served as an engineer under Julius Caesar during the first Gallic Wars (58–50 BC). The treatise was dedicated to Emperor Augustus. As Vitruvius defined the concept in the first chapters of the treatise, he mentioned the three prerequisites of architecture are firmness (firmitas), commodity (utilitas), and delight (venustas), which require the architects to be equipped with a varied kind of learning and knowledge of many branches. Moreover, Vitruvius identified the "Six Principles of Design" as order (ordinatio), arrangement (dispositio), proportion (eurythmia), symmetry (symmetria), propriety (decor) and economy (distributio). Among the six principles, proportion interrelates and supports all the other factors in geometrical forms and arithmetical ratios.
The word symmetria, usually translated to "symmetry" in modern renderings, in ancient times m
|
https://en.wikipedia.org/wiki/List%20of%20backup%20software
|
This is a list of notable backup software that performs data backups. Archivers, transfer protocols, and version control systems are often used for backups but only software focused on backup is listed here. See Comparison of backup software for features.
Free and open-source software
Commercial and closed-source software
Defunct software
See also
Comparison of file synchronization software
Comparison of online backup services
Data recovery
File synchronization
List of data recovery software
Remote backup service
Tape management system
Notes
References
Backup software
|
https://en.wikipedia.org/wiki/Roborior
|
Roborior is a robot manufactured by the robotics company Tmsuk and marketed by Sanyo. It is used both for lighting and guarding homes. Roborior is roughly the size of a watermelon and can produce different hues of color ranging from blue, purple, and orange. The Roborior is also equipped with a digital video camera that can stream live video directly to the owner's cell phone if it detects an intruder. The Roborior can be controlled remotely with a hand set, much like a Remote control vehicle, as well. It was introduced in Japan in late 2005 and was priced at 280,000 Japanese yen. The name is a portmanteau of robot and interior.
References
External links
Description of the Roborior
Domestic robots
Robots of Japan
2005 robots
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https://en.wikipedia.org/wiki/Joseph%20L.%20Gormley
|
Joseph Leo Gormley (May 22, 1914 – June 6, 2004) was the chief of chemistry and toxicology for the FBI.
Born in Clinton, Massachusetts, he was raised in Somerville, Massachusetts. Gormley received his bachelor's and master's degrees in chemistry from Boston College. With his wife Frances he fathered and raised nine children.
In 1940, he moved to Washington, D.C., and joined the Federal Bureau of Investigation. Gormley earned two law degrees from Georgetown University and a master's degree in forensic science from George Washington University.
He spent more than thirty three years with the FBI, investigating some of the agency's most famous cases, including the Great Brinks Robbery in 1950 and the 1964 murders of three young civil rights workers, which became known as the "Mississippi Burning" case. He served as an expert witness in numerous trials, testifying on his knowledge of chemistry, toxicology and arson. For more than 20 years, Gormley supervised a program that developed the use of lie detector tests for investigative purposes.
He retired from the FBI in 1973, and moved temporarily to Maine to direct the Maine State Police Crime Laboratory. After returning to the Washington, D.C., area he worked in the research and training divisions of the International Association of Chiefs of Police. In addition to his work at the IACP, Gormley worked as a consultant for law enforcement matters in his later years. The former president of the Mid-Atlantic Association of Forens
|
https://en.wikipedia.org/wiki/Scattering%20parameters
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Scattering parameters or S-parameters (the elements of a scattering matrix or S-matrix) describe the electrical behavior of linear electrical networks when undergoing various steady state stimuli by electrical signals.
The parameters are useful for several branches of electrical engineering, including electronics, communication systems design, and especially for microwave engineering.
The S-parameters are members of a family of similar parameters, other examples being: Y-parameters, Z-parameters, H-parameters, T-parameters or ABCD-parameters. They differ from these, in the sense that S-parameters do not use open or short circuit conditions to characterize a linear electrical network; instead, matched loads are used. These terminations are much easier to use at high signal frequencies than open-circuit and short-circuit terminations. Contrary to popular belief, the quantities are not measured in terms of power (except in now-obsolete six-port network analyzers). Modern vector network analyzers measure amplitude and phase of voltage traveling wave phasors using essentially the same circuit as that used for the demodulation of digitally modulated wireless signals.
Many electrical properties of networks of components (inductors, capacitors, resistors) may be expressed using S-parameters, such as gain, return loss, voltage standing wave ratio (VSWR), reflection coefficient and amplifier stability. The term 'scattering' is more common to optical engineering than RF engineering,
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https://en.wikipedia.org/wiki/Neritic%20zone
|
The neritic zone (or sublittoral zone) is the relatively shallow part of the ocean above the drop-off of the continental shelf, approximately in depth.
From the point of view of marine biology it forms a relatively stable and well-illuminated environment for marine life, from plankton up to large fish and corals, while physical oceanography sees it as where the oceanic system interacts with the coast.
Definition (marine biology), context, extra terminology
In marine biology, the neritic zone, also called coastal waters, the coastal ocean or the sublittoral zone, refers to that zone of the ocean where sunlight reaches the ocean floor, that is, where the water is never so deep as to take it out of the photic zone.
It extends from the low tide mark to the edge of the continental shelf, with a relatively shallow depth extending to about 200 meters (660 feet).
Above the neritic zone lie the intertidal (or eulittoral) and supralittoral zones; below it the continental slope begins, descending from the continental shelf to the abyssal plain and the pelagic zone.
Within the neritic, marine biologists also identify the following:
The infralittoral zone is the algal-dominated zone down to around five metres below the low water mark.
The circalittoral zone is the region beyond the infralittoral, which is dominated by sessile animals such as oysters.
The subtidal zone is the region of the neritic zone which is below the intertidal zone, therefore never exposed to the atmosphere.
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https://en.wikipedia.org/wiki/Slipstream%20%28disambiguation%29
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A slipstream is a pocket of reduced pressure following behind an object moving through a fluid medium.
Slipstream may also refer to:
Computing
Slipstream (computer science), the technique of running a shortened program concurrently and ahead of the execution of the full program
Slipstream (computing), a slang term for merging patches or updates into the original installation sources of a program
Slipstream 5000, a 1995 racing game for PC
Fiction
Slipstream (genre), a literary genre that pushes the boundary between traditional fiction and either science fiction and/or fantasy
Slipstream (radio drama), a BBC Radio 7 science fiction series
Slipstream (science fiction), fictional methods of faster-than-light travel
Characters
Slipstream (comics), a Marvel Comics superhero character
Slipstream (Transformers), several robot characters in the Transformers franchise including Transformers: Animated
Slip Stream (G.I. Joe), a pilot character in the G.I. Joe franchise
Film
Slipstream (unfinished film), an unfinished Steven Spielberg movie
Slipstream (1973 film), a Canadian drama directed by David Acomba
Slipstream (video), a 1980 concert by Jethro Tull
Slipstream (1989 film), a post-apocalyptic adventure directed by Steven Lisberger
Slipstream (2005 film), a time travel thriller directed by David van Eyssen
Slipstream (2007 film), a drama written and directed by Anthony Hopkins
Music
Slipstream (band), a UK indie band
Albums
Slipstream (Bonnie Raitt album), 2012
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https://en.wikipedia.org/wiki/Arithmetic%20geometry
|
In mathematics, arithmetic geometry is roughly the application of techniques from algebraic geometry to problems in number theory. Arithmetic geometry is centered around Diophantine geometry, the study of rational points of algebraic varieties.
In more abstract terms, arithmetic geometry can be defined as the study of schemes of finite type over the spectrum of the ring of integers.
Overview
The classical objects of interest in arithmetic geometry are rational points: sets of solutions of a system of polynomial equations over number fields, finite fields, p-adic fields, or function fields, i.e. fields that are not algebraically closed excluding the real numbers. Rational points can be directly characterized by height functions which measure their arithmetic complexity.
The structure of algebraic varieties defined over non-algebraically closed fields has become a central area of interest that arose with the modern abstract development of algebraic geometry. Over finite fields, étale cohomology provides topological invariants associated to algebraic varieties. p-adic Hodge theory gives tools to examine when cohomological properties of varieties over the complex numbers extend to those over p-adic fields.
History
19th century: early arithmetic geometry
In the early 19th century, Carl Friedrich Gauss observed that non-zero integer solutions to homogeneous polynomial equations with rational coefficients exist if non-zero rational solutions exist.
In the 1850s, Leopold Kronec
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https://en.wikipedia.org/wiki/Slovak%20University%20of%20Technology%20in%20Bratislava
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Slovak University of Technology in Bratislava (STU) () is the biggest and oldest university of technology in Slovakia. In the 2012 Academic Ranking of World Universities it was ranked in the first 150 in Computer Science, the only university in central Europe in the first 200. However, it lost this position in the two following years.
University structure
Faculty of Civil Engineering
Faculty of Mechanical Engineering
Faculty of Electrical Engineering and Information Technology
Faculty of Chemical and Food Technology
Faculty of Architecture and Design
Faculty of Materials Science and Technology (in Trnava)
Faculty of Informatics and Information Technologies
Institute of Management
Institute of Engineering Studies
European Alliance for Innovation
The Slovak University of Technology in Bratislava signed a Memorandum of Understanding with the European Alliance for Innovation on 3 May 2013. The signators were the president of the European Alliance for Innovation, professor Imrich Chlamtac and the rector of the Slovak University of Technology in Bratislava, Robert Redhammer.
The purpose of this cooperation is to help innovation made in the STU to reach the market, as well as create a base of operations for EAI in Central Europe.
See also
ESDP-Network
References
External links
Universities and colleges established in 1937
Education in Bratislava
1937 establishments in Czechoslovakia
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https://en.wikipedia.org/wiki/Alphonse%20Ouimet
|
Joseph-Alphonse Ouimet, (June 12, 1908 – December 20, 1988) was a Canadian television pioneer and president of the Canadian Broadcasting Corporation (CBC) from 1958 to 1967.
Born in Montreal, Ouimet received a degree in electrical engineering from McGill University in 1932. In 1932, he helped design, build, and demonstrate the first Canadian television set. In 1934, he joined the Canadian Radio Broadcasting Commission, which became the CBC, and was responsible for setting up and running CBC's national radio service. He was involved in launching television broadcasting on the CBC.
After retiring from the CBC, Ouimet became, in 1969, chairman of Telesat Canada, which built and launched many of Canada's communications satellites. He retired in 1980.
In 1968, Ouimet was made a Companion of the Order of Canada.
Ouimet died in 1988 in the city of his birth.
External links
Alphonse Ouimet's entry in The Canadian Encyclopedia
Presidents of the Canadian Broadcasting Corporation
20th-century Canadian civil servants
Companions of the Order of Canada
Businesspeople from Montreal
1908 births
1988 deaths
Burials at Notre Dame des Neiges Cemetery
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https://en.wikipedia.org/wiki/Comprehension
|
Comprehension may refer to:
Comprehension (logic), the totality of intensions, that is, properties or qualities, that an object possesses
Comprehension approach, several methodologies of language learning that emphasize understanding language rather than speaking
Comprehension axiom, an axiom in Zermelo–Fraenkel set theory in mathematics
List comprehension, an adaptation of mathematical set notation to represent lists in computer science
Reading comprehension, a measurement of the understanding of a passage of text
Understanding, ability to think about and to deal adequately with an idea
See also
Comprehensive (disambiguation)
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https://en.wikipedia.org/wiki/Depletion%20region
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In semiconductor physics, the depletion region, also called depletion layer, depletion zone, junction region, space charge region or space charge layer, is an insulating region within a conductive, doped semiconductor material where the mobile charge carriers have been diffused away, or have been forced away by an electric field. The only elements left in the depletion region are ionized donor or acceptor impurities. This region of uncovered positive and negative ions is called the depletion region due to the depletion of carriers in this region, leaving none to carry a current. Understanding the depletion region is key to explaining modern semiconductor electronics: diodes, bipolar junction transistors, field-effect transistors, and variable capacitance diodes all rely on depletion region phenomena.
Formation in a p–n junction
A depletion region forms instantaneously across a p–n junction. It is most easily described when the junction is in thermal equilibrium or in a steady state: in both of these cases the properties of the system do not vary in time; they have been called dynamic equilibrium.
Electrons and holes diffuse into regions with lower concentrations of them, much as ink diffuses into water until it is uniformly distributed. By definition, the N-type semiconductor has an excess of free electrons (in the conduction band) compared to the P-type semiconductor, and the P-type has an excess of holes (in the valence band) compared to the N-type. Therefore, when N-do
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https://en.wikipedia.org/wiki/Ring%20structure
|
Ring structure may refer to:
Chiastic structure, a literary technique
Heterocyclic compound, a chemical structure
Ring (mathematics), an algebraic structure
See also
Ring (disambiguation)
|
https://en.wikipedia.org/wiki/IMCB
|
IMCB may refer to:
International Medical Commission on Bhopal
Institute of Molecular and Cell Biology (disambiguation)
Independent Mobile Classification Board, a defunct NGO replaced by the British Board of Film Classification
|
https://en.wikipedia.org/wiki/Allegheny%20Observatory
|
The Allegheny Observatory is an American astronomical research institution, a part of the Department of Physics and Astronomy at the University of Pittsburgh. The facility is listed on the National Register of Historic Places (ref. # 79002157, added June 22, 1979) and is designated as a Pennsylvania state and Pittsburgh History and Landmarks Foundation historic landmark.
History
The observatory was founded on February 15, 1859, in the city of Allegheny, Pennsylvania (incorporated into the City of Pittsburgh in 1907) by a group of wealthy industrialists calling themselves the Allegheny Telescope Association. The observatory's initial purpose was for general public education as opposed to research, but by 1867 the revenues derived from this had receded. The facility was then donated to the Western University of Pennsylvania, today known as the University of Pittsburgh.
The University hired Samuel Pierpont Langley to be the first director. One of the research programs initiated under his leadership was of sunspots. He drew very detailed drawings of sunspots which are still used in astronomical textbooks to this day. He also had the building expanded to include dark rooms, class rooms, dormitories, and a lecture hall.
In 1869, Langley created income for observatory by selling subscription service to time that was accurately determined by astronomical measurements and transmitted over telegraphs to customers. The Pennsylvania Railroad was the most influential subscriber to t
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https://en.wikipedia.org/wiki/IEEE%20Transactions%20on%20Information%20Theory
|
IEEE Transactions on Information Theory is a monthly peer-reviewed scientific journal published by the IEEE Information Theory Society. It covers information theory and the mathematics of communications. It was established in 1953 as IRE Transactions on Information Theory. The editor-in-chief is Muriel Médard (Massachusetts Institute of Technology). As of 2007, the journal allows the posting of preprints on arXiv.
According to Jack van Lint, it is the leading research journal in the whole field of coding theory. A 2006 study using the PageRank network analysis algorithm found that, among hundreds of computer science-related journals, IEEE Transactions on Information Theory had the highest ranking and was thus deemed the most prestigious. ACM Computing Surveys, with the highest impact factor, was deemed the most popular.
References
External links
List of past editors-in-chief
Engineering journals
Information theory
Transactions on Information Theory
Computer science journals
Cryptography journals
Academic journals established in 1953
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https://en.wikipedia.org/wiki/Crossed%20module
|
In mathematics, and especially in homotopy theory, a crossed module consists of groups and , where acts on by automorphisms (which we will write on the left, , and a homomorphism of groups
that is equivariant with respect to the conjugation action of on itself:
and also satisfies the so-called Peiffer identity:
Origin
The first mention of the second identity for a crossed module seems to be in footnote 25 on p. 422 of J. H. C. Whitehead's 1941 paper cited below, while the term 'crossed module' is introduced in his 1946 paper cited below. These ideas were well worked up in his 1949 paper 'Combinatorial homotopy II', which also introduced the important idea of a free crossed module. Whitehead's ideas on crossed modules and their applications are developed and explained in the book by Brown, Higgins, Sivera listed below. Some generalisations of the idea of crossed module are explained in the paper of Janelidze.
Examples
Let be a normal subgroup of a group . Then, the inclusion
is a crossed module with the conjugation action of on .
For any group G, modules over the group ring are crossed G-modules with d = 0.
For any group H, the homomorphism from H to Aut(H) sending any element of H to the corresponding inner automorphism is a crossed module.
Given any central extension of groups
the surjective homomorphism
together with the action of on defines a crossed module. Thus, central extensions can be seen as special crossed modules. Conversely, a cros
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https://en.wikipedia.org/wiki/David%20Rosenhan
|
David L. Rosenhan (; November 22, 1929 – February 6, 2012) was an American psychologist. He is best known for the Rosenhan experiment, a study challenging the validity of psychiatry diagnoses.
Biography
Rosenhan received his Bachelor of Arts degree in mathematics in 1951 from Yeshiva College, his master's degree in economics in 1953 and his doctorate in psychology in 1958, both from Columbia University. As further described in his obituary published by the American Psychological Association (APA), "Rosenhan was a pioneer in applying psychological methods to the practice of law, including the examination of expert witnesses, jury selection, and jury deliberation." He was a professor of law and of psychology at Stanford University from 1971 until his retirement in 1998. Before joining the Stanford Law School faculty, he was a member of the faculties of Swarthmore College, Princeton University, Haverford College, and the University of Pennsylvania. He also served as a research psychologist at the Educational Testing Service. He later became a professor emeritus in law and psychology at Stanford University. Rosenhan was a fellow of the American Association for the Advancement of Science and various psychological societies, including the APA, and had been a visiting fellow at Wolfson College at Oxford University.
Rosenhan died on February 6, 2012, at the age of 82.
Research
Rosenhan believed that there are seven main features of abnormality: suffering; maladaptiveness; vividne
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https://en.wikipedia.org/wiki/Teleoperation
|
Teleoperation (or remote operation) indicates operation of a system or machine at a distance. It is similar in meaning to the phrase "remote control" but is usually encountered in research, academia and technology. It is most commonly associated with robotics and mobile robots but can be applied to a whole range of circumstances in which a device or machine is operated by a person from a distance.
Teleoperation can be considered a human-machine system. For example, ArduPilot provides a spectrum of autonomy ranging from manual control to full autopilot for autonomous vehicles.
The term teleoperation is in use in research and technical communities as a standard term for referring to operation at a distance. This is as opposed to telepresence which is a less standard term and might refer to a whole range of existence or interaction that include a remote connotation.
History
The 19th century saw many inventors working on remotely operated weapons (torpedoes) including prototypes built by John Louis Lay (1872), John Ericsson (1873), Victor von Scheliha (1873), and the first practical wire guided torpedo, the Brennan torpedo, patented by Louis Brennan in 1877. In 1898, Nikola Tesla demonstrated a remotely controlled boat with a patented wireless radio guidance system that he tried to market to the United States military, but was turned down.
Teleoperation is now moving into the hobby industry with first-person view (FPV) equipment. FPV equipment mounted on hobby cars, pla
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