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https://en.wikipedia.org/wiki/Bruce%20Webster
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Bruce F. Webster is an American academic and software engineer. He is currently a principal at Bruce F. Webster & Associates and an adjunct professor in computer science at Brigham Young University.
Early life and education
Webster studied computer science at Brigham Young University, graduating in 1978 with a bachelor's degree. He had received a full National Merit Scholarship for his studies. He went on to do graduate work in computer science at the University of Houston-Clear Lake in Houston, Texas.
Career
Webster, since 1980, has written over 150 articles on the computer industry and software development. He has also written four books on information technology (IT) issues, including The NeXT book, Pitfalls of Object-Oriented Development, The Art of ‘Ware, and The Y2K Survival Guide, and contributed to two others. He authored PricewaterhouseCoopers' 2000 white paper, Patterns in IT Litigation: System Failure. He also wrote for two years as an IT management columnist for Baseline.
In the 1980s, Webster wrote articles and columns for BYTE and Macworld, and taught computer science at his alma mater, Brigham Young University. In the 1990s, he went on to help found another software startup, Pages Software Inc., where he served as Chief Technical Officer and chief software architect for five years. He then served as Chief Technical Officer at Object Systems Group (now OSG), reviewing troubled corporate IT projects, and subsequently worked as a Director at PricewaterhouseC
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https://en.wikipedia.org/wiki/Paul%20Hudson
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Paul David Hudson (born 27 February 1971) is an English weather presenter for BBC Yorkshire and BBC Yorkshire and Lincolnshire. Hudson was born and raised in Keighley, West Yorkshire. He was made an Honorary Fellow of Bradford College in 2014.
After reading geophysics and planetary physics at Newcastle University, Hudson joined the Met Office and trained for two years at Leeds Weather Centre. Hudson combined this with a two-year stint as a weather presenter for BBC Look North and for the BBC local radio stations in Leeds, York, Humberside and Sheffield.
Hudson is known for his tongue-in-cheek banter with BBC Look North presenter Harry Gration, and also Peter Levy, presenter of BBC Look North for East Yorkshire, Lincolnshire, North West Norfolk and parts of Nottinghamshire via the Belmont transmitter.
Early life
Hudson was born in Keighley, West Riding of Yorkshire. His parents purchased his first 'kids weather centre' when he was seven, and by the age of twelve he was compiling his own meteorological records (now archived by Keighley Library) and writing for local newspapers Keighley News and Telegraph & Argus. He went to the Brontë Middle School and Oakbank School on Oakworth Road in Keighley.
Hudson has a first-class degree in geophysics and planetary physics from the University of Newcastle. His early memories of local weather forecasting came from fellow Yorkshireman, Doncaster's Bob Rust.
Paul Hudson was present during the catastrophic fire at Valley parade in 19
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https://en.wikipedia.org/wiki/Three-center%20bond
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In chemistry, there are two types of three-center bonds:
Three-center two-electron bond, found in electron-deficient compounds such as boranes
Three-center four-electron bond, found in hypervalent compounds such as the noble gas compounds
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https://en.wikipedia.org/wiki/CRTP
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CRTP has several meanings in computer science.
Curiously recurring template pattern in the C++ programming language
Diapolycopene oxygenase, an enzyme
Cardiac resynchronization therapy pacemaker
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https://en.wikipedia.org/wiki/BID%20770
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The BID 770 was a British-built electronic cryptography device, codenamed TOPIC. It was also used by Canada's foreign service under the codename TENEC. TOPIC was brought into service in 1977, and became obsolete in 1995.
TOPIC was used to protect telegraph traffic, and replaced the earlier mechanical system called ROCKEX. It could be operated in both on- and off-line modes. Weighing 65 lb, the machine used diode–transistor logic instead of single transistors.
External links
Jerry Proc's page on the BID 770
Encryption devices
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https://en.wikipedia.org/wiki/Brominated%20flame%20retardant
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Brominated flame retardants (BFRs) are organobromine compounds that have an inhibitory effect on combustion chemistry and tend to reduce the flammability of products containing them. The brominated variety of commercialized chemical flame retardants comprise approximately 19.7% of the market. They are effective in plastics and textile applications like electronics, clothes and furniture.
Types of compounds
Many different BFRs are produced synthetically with widely varying chemical properties. There are several groups:
Polybrominated diphenyl ethers (PBDEs): DecaBDE, OctaBDE (not manufactured anymore), PentaBDE (not manufactured anymore, the first BFR, commercialized in the 1950s)
Polybrominated biphenyl (PBB), not manufactured anymore
Brominated cyclohydrocarbons
Other brominated flame retardants with different properties and mechanisms
Decabromodiphenyl ether (Deca-BDE or DeBDE) - In August 2012, the UK authorities proposed decabromodiphenyl ether (Deca-BDE or DeBDE) as a candidate for Authorisation under the EU‘s regulatory regime on chemicals, REACH. On 5 July 2013 ECHA withdrew Deca-BDE from its list of priority substances for Authorisation under REACH, therefore closing the public consultation. On 1 August 2014, ECHA submitted a restriction proposal for Deca-BDE. The agency is proposing a restriction on the manufacture, use and placing on the market of the substance and of mixtures and articles containing it. On 17 September 2014, ECHA submitted the restriction re
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https://en.wikipedia.org/wiki/Latin%20letters%20used%20in%20mathematics%2C%20science%2C%20and%20engineering
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Many letters of the Latin alphabet, both capital and small, are used in mathematics, science, and engineering to denote by convention specific or abstracted constants, variables of a certain type, units, multipliers, or physical entities. Certain letters, when combined with special formatting, take on special meaning.
Below is an alphabetical list of the letters of the alphabet with some of their uses. The field in which the convention applies is mathematics unless otherwise noted.
Aa
A represents:
the first point of a triangle
the digit "10" in hexadecimal and other positional numeral systems with a radix of 11 or greater
the unit ampere for electric current in physics
the area of a figure
the mass number or nucleon number of an element in chemistry
the Helmholtz free energy of a closed thermodynamic system of constant pressure and temperature
a vector potential, in electromagnetics it can refer to the magnetic vector potential
an Abelian group in abstract algebra
the Glaisher–Kinkelin constant
atomic weight, denoted by Ar
work in classical mechanics
the pre-exponential factor in the Arrhenius Equation
electron affinity
represents the algebraic numbers or affine space in algebraic geometry.
A blood type
A spectral type
a represents:
the first side of a triangle (opposite point A)
the scale factor of the expanding universe in cosmology
the acceleration in mechanics equations
the first constant in a linear equation
a constant in a polynomial
the unit are for area (100 m2
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https://en.wikipedia.org/wiki/Ring%20strain
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In organic chemistry, ring strain is a type of instability that exists when bonds in a molecule form angles that are abnormal. Strain is most commonly discussed for small rings such as cyclopropanes and cyclobutanes, whose internal angles are substantially smaller than the idealized value of approximately 109°. Because of their high strain, the heat of combustion for these small rings is elevated.
Ring strain results from a combination of angle strain, conformational strain or Pitzer strain (torsional eclipsing interactions), and transannular strain, also known as van der Waals strain or Prelog strain. The simplest examples of angle strain are small cycloalkanes such as cyclopropane and cyclobutane.
Ring strain energy can be attributed to the energy required for the distortion of bond and bond angles in order to close a ring.
Ring strain energy is believed to be the cause of accelerated rates in altering ring reactions. Its interactions with traditional bond energies change the enthalpies of compounds effecting the kinetics and thermodynamics of ring strain reactions.
History
Ring strain theory was first developed by German chemist Adolf von Bayer in 1890. Previously, the only bonds believed to exist were torsional and steric; however, Bayer's theory became based on the interactions between the two strains.
Bayer's theory was based on the assumption that ringed compounds were flat. Later, around the same time, Hermann Sachse formed his postulation that compound ri
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https://en.wikipedia.org/wiki/Alain%20Pompidou
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Alain Pompidou (born 5 April 1942) is a French scientist and politician. A former professor of histology, embryology and cytogenetics, he was the fourth president of the European Patent Office (EPO) from 1 July 2004 to 30 June 2007. He is the adopted son of Georges Pompidou, former President of France.
Biography
Pompidou was born in Paris.
Professor of histology, embryology and cytogenetics (1974-2004)
He took doctorates in medicine, biology and science. From 1974 to 2004, he was professor of histology, embryology and cytogenetics in the medical faculty of the University of Paris. Until 2004 he was also director of the laboratory of the Cochin – St Vincent de Paul – La Roche Guyon Hospital in Paris, head of the cytogenetics and pathology department, and chairman of the hospital group's advisory board. He hold tenures at the University of Alabama at Birmingham and at the Memorial Sloan-Kettering Cancer Center in New York.
He is also the author of numerous articles and monographs on science, ethics and society, as well as on biomedical ethics.
Advisor for science policy and science ethics
Pompidou served on the consultative and scientific committee of numerous national, European and international organisations, including the World Health Organization (WHO), UNESCO and the European Commission.
From 1990 to 2004, he was a member and founder of the French Academy of Technologies.
Between 1986 and 1997 he acted as a special adviser to the French prime minister, the minis
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https://en.wikipedia.org/wiki/Torricelli%27s%20equation
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In physics, Torricelli's equation, or Torricelli's formula, is an equation created by Evangelista Torricelli to find the final velocity of a moving object with constant acceleration along an axis (for example, the x axis) without having a known time interval.
The equation itself is:
where
is the object's final velocity along the x axis on which the acceleration is constant.
is the object's initial velocity along the x axis.
is the object's acceleration along the x axis, which is given as a constant.
is the object's change in position along the x axis, also called displacement.
In this and all subsequent equations in this article, the subscript (as in ) is implied, but is not expressed explicitly for clarity in presenting the equations.
This equation is valid along any axis on which the acceleration is constant.
Derivation
Without differentials and integration
Begin with the definition of acceleration:
where is the time interval. This is true because the acceleration is constant. The left hand side is this constant value of the acceleration and the right hand side is the average acceleration. Since the average of a constant must be equal to the constant value, we have this equality. If the acceleration was not constant, this would not be true.
Now solve for the final velocity:
Square both sides to get:
The term also appears in another equation that is valid for motion with constant acceleration: the equation for the final position of an object moving with co
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https://en.wikipedia.org/wiki/Bernoulli%20equation
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Bernoulli equation may refer to:
Bernoulli differential equation
Bernoulli's equation, in fluid dynamics
Euler–Bernoulli beam equation, in solid mechanics
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https://en.wikipedia.org/wiki/Institute%20of%20Psychiatry%20%28disambiguation%29
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Institute of Psychiatry may refer to:
Institute of Psychiatry, Psychology and Neuroscience, previously known as the Institute of Psychiatry, at King's College London, UK
Centre for Addiction and Mental Health (College Street site), formerly the Clarke Institute of Psychiatry, in Toronto, Canada
Institute of Psychiatry and Human Behaviour, Goa Medical College, India
Max Planck Institute of Psychiatry, Munich, Germany
Central Institute of Psychiatry, Kanke, India
Somdet Chaopraya Institute of Psychiatry, Bangkok, Thailand
Institute of Psychiatry at Ain Shams University Faculty of Medicine, Cairo, Egypt
Stone Institute of Psychiatry at Northwestern Memorial Hospital, Chicago, U.S.
Sir Cowasjee Jehangir Institute of Psychiatry, Hyderabad, India
Institute of Psychiatry at the Benazir Bhutto Hospital, Rawalpindi, Pakistan
Institute of Psychiatry at MUSC Health Medical Center, Medical University of South Carolina
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https://en.wikipedia.org/wiki/Csaba%20Csere
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Csaba Csere ( ) is a former technical director and editor-in-chief of Car and Driver magazine.
Csere is an American of Hungarian descent. He earned a bachelor's degree in mechanical engineering at the Massachusetts Institute of Technology in 1975. He went on to join Ford Motor Company's Advanced Engine Engineering Office. He joined Car and Driver magazine as its technical editor in 1980. He specialized in stories about technical issues and first-person experiences in competition machines ranging from NASCAR stock cars to Formula One cars. In the process, he raced in fifteen 24-hour events and performed an automotive backflip at over 200 mph on the Bonneville Salt Flats.
Csere became editor-in-chief in 1993 and concentrated on integrating Car and Driver's TV, Internet, and radio efforts. He presided over a controversial redesign of the magazine, launched in December 2006 and refined during 2007. The cover featured capitalized headlines, often with an exclamation point, and featured bands of yellow. Inside, there was further prominent use of yellow, his favourite color. Additional yellow coloration was to be found on the Car and Driver website. The redesign was roundly criticized in the 'Backfires' (Reader's Letters) section of the March 2007 issue. In that column, the editor admitted to receiving 164 letters against the redesign and 13 for, but stated: "We paid big bucks for this yellow redesign and we ain't going back - Ed".
On December 16, 2008 — according to the of
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https://en.wikipedia.org/wiki/Mark%20Rudd
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Mark William Rudd (born June 2, 1947) is an American political organizer, mathematics instructor, anti-war activist and counterculture icon who was involved with the Weather Underground in the 1960s.
Rudd became a member of the Columbia University chapter of Students for a Democratic Society (SDS) in 1963. By 1968, he had emerged as a leader for Columbia's SDS chapter. During the 1968 Columbia University Protests, he served as spokesperson for dissident students protesting a variety of issues, particularly the Vietnam War. As the war escalated, Mark Rudd worked with other youth movement leaders to take SDS in a more militant direction. While much of the general membership of SDS refused to countenance violence, Rudd together with some other prominent SDS members formed a paramilitary organization inspired by the Red Guard, referring to themselves collectively as "Weatherman" after the lyrics from a famous Bob Dylan song.
Rudd went "underground" in 1970, hiding from law enforcement following the Greenwich Village townhouse explosion that killed three of his Weather Underground peers. He surrendered to authorities in 1977 and served a short jail sentence. He taught mathematics at Central New Mexico Community College, and retired in Albuquerque, New Mexico. Rudd has since expressed regret for his role in the Weather Underground, and advocates for nonviolence and electoral change.
Early life
Rudd was born in Irvington, New Jersey. His father, Jacob S. Rudd (1909–1995), was b
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https://en.wikipedia.org/wiki/Bundle%20gerbe
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In mathematics, a bundle gerbe is a geometrical model of certain 1-gerbes with connection, or equivalently of a 2-class in Deligne cohomology.
Topology
-principal bundles over a space (see circle bundle) are geometrical realizations of 1-classes in Deligne cohomology which consist of 1-form connections and 2-form curvatures. The topology of a bundle is classified by its Chern class, which is an element of , the second integral cohomology of .
Gerbes, or more precisely 1-gerbes, are abstract descriptions of Deligne 2-classes, which each define an element of , the third integral cohomology of M.
As a cohomology class in Deligne cohomology
Recall for a smooth manifold the p-th Deligne cohomology groups are defined by the hypercohomology of the complex called the weight q Deligne complex, where is the sheaf of germs of smooth differential k-forms tensored with . So, we write for the Deligne-cohomology groups of weight . In the case the Deligne complex is then
We can understand the Deligne cohomology groups by looking at the Cech resolution giving a double complex. There is also an associated short exact sequence
where are the closed germs of complex valued 2-forms on and is the subspace of such forms where period integrals are integral. This can be used to show are the isomorphism classes of bundle-gerbes on a smooth manifold , or equivalently, the isomorphism classes of -bundles on .
History
Historically the most popular construction of a gerbe is a categor
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https://en.wikipedia.org/wiki/Paul%20Steinhardt
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Paul Joseph Steinhardt (born December 25, 1952) is an American theoretical physicist whose principal research is in cosmology and condensed matter physics. He is currently the Albert Einstein Professor in Science at Princeton University, where he is on the faculty of both the Departments of Physics and of Astrophysical Sciences.
Steinhardt is best known for his development of new theories of the origin, evolution and future of the universe. He is also well known for his exploration of a new form of matter, known as quasicrystals, which were thought to exist only as man-made materials until he co-discovered the first known natural quasicrystal in a museum sample. He subsequently led a separate team that followed up that discovery with several more examples of natural quasicrystals recovered from the wilds of the Kamchatka Peninsula in far eastern Russia. Several years later, he and collaborators reported the accidental synthesis of a previously unknown type of quasicrystal in the remnants of the first atomic bomb test on July 16, 1945, at Alamagordo, New Mexico.
He has written two popular books on these topics. Endless Universe: Beyond the Big Bang (2007), co-authored with Neil Turok, describes the early struggles in challenging the widely accepted big bang theory and the subsequent development of the bouncing or cyclic theories of the universe, which are currently being explored and tested. The Second Kind of Impossible: The Extraordinary Quest for a New Form of Matter (2
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https://en.wikipedia.org/wiki/Lanczos%20approximation
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In mathematics, the Lanczos approximation is a method for computing the gamma function numerically, published by Cornelius Lanczos in 1964. It is a practical alternative to the more popular Stirling's approximation for calculating the gamma function with fixed precision.
Introduction
The Lanczos approximation consists of the formula
for the gamma function, with
Here g is a real constant that may be chosen arbitrarily subject to the restriction that Re(z+g+) > 0. The coefficients p, which depend on g, are slightly more difficult to calculate (see below). Although the formula as stated here is only valid for arguments in the right complex half-plane, it can be extended to the entire complex plane by the reflection formula,
The series A is convergent, and may be truncated to obtain an approximation with the desired precision. By choosing an appropriate g (typically a small integer), only some 5–10 terms of the series are needed to compute the gamma function with typical single or double floating-point precision. If a fixed g is chosen, the coefficients can be calculated in advance and, thanks to partial fraction decomposition, the sum is recast into the following form:
Thus computing the gamma function becomes a matter of evaluating only a small number of elementary functions and multiplying by stored constants. The Lanczos approximation was popularized by Numerical Recipes, according to which computing the gamma function becomes "not much more difficult than other built-i
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https://en.wikipedia.org/wiki/W%C5%82adys%C5%82aw%20%C5%9Alebodzi%C5%84ski
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Władysław Ślebodziński () (February 6, 1884 – January 3, 1972) was a Polish mathematician.
Władysław Ślebodziński was born in Pysznica, Poland and educated at the Jagiellonian University in Kraków (1903-1908) where he subsequently held a teaching position until 1921. After 1921, he lectured at the State High School of Mechanical Engineering Poznań and in the thirties, he was a visiting lecturer at the Poznań University and Warsaw University until 1939. During the Second World War, he gave underground lectures, leading to his imprisonment. He survived three German concentration camps: Auschwitz (1942 - 1945), where he gave underground university-level lectures as prisoner no. 79053, Gross-Rosen and Nordhausen.
In 1945 he became a joint professor at Wrocław University and at the Wrocław University of Technology, and from 1951 he was a professor at the Wrocław University of Technology. With Bronisław Knaster, Edward Marczewski and Hugo Steinhaus, he was a co-founder of the mathematical journal Colloquium Mathematicum.
From 1949 until 1960, he was a Professor of the Institute of Mathematics of the Polish Academy of Sciences.
Władysław Ślebodziński's main interest was differential geometry. In 1931, he introduced the definition of the Lie derivative, although according to J.A. Schouten, the term Lie derivative occurred first in a two-part paper by van Dantzig.
He was the advisor of 11 PhD theses. He was also doctor honoris causa at the Wrocław University of Technology (1965),
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https://en.wikipedia.org/wiki/Franciszek%20Leja
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Franciszek Leja (27 January 1885 in Grodzisko Górne near Leżajsk – 11 October 1979 in Kraków, Poland) was a Polish mathematician.
He was born to a poor peasant family in the southeastern Poland. After graduating from the University of Lwów he was a teacher of mathematics and physics in high schools from 1910 until 1923, among others in Kraków. From 1924 until 1936 he was a professor at the Warsaw University of Technology and Warsaw University, from 1936 until 1960 in the Jagiellonian University.
He was captured by German Nazi during Sonderaktion Krakau and sent with 183 Polish professors of the Jagiellonian University and University of Technology to Sachsenhausen concentration camp. After international protest by prominent Italians including Benito Mussolini and the Vatican, 101 professors who were older than 40 were released from Sachsenhausen on February 8, 1940. Unfortunately Leja, older than 40, was not in the group of released prisoners. He stayed in a concentration camp until May 1940 when he returned to Kraków. In Kraków bad news were waiting for him: the university was closed, Leja's apartment was taken over by Nazi. The homeless couple with no income decided to move to Grodzisko Górne where they have a small house and garden. They got a permission from Gestapo and left Kraków. In Grodzisko Leja wrote the book on the calculus Rachunek różniczkowy i całkowy ze wstępem do równań różniczkowych.
Since 1948 he worked for the Institute of Mathematics of the Polish Acade
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https://en.wikipedia.org/wiki/Antoni%20%C5%81omnicki
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Antoni Marian Łomnicki (17 January 1881 – 4 July 1941) was a Polish mathematician. He contributed to applied mathematics and cartography. He was the author of several textbooks of mathematics and was an influential mathematics teacher at the University of Lwów.
Life and work
Antoni Łomnicki was born in Lwów, the son of Marian Łomnicki. He was educated at the Lviv's IV Gymnasium, Jan Kazimierz University in Lwów in Poland (1899-1903). . His teachers included Józef Puzyna, Jan Rajewski, Stanisław Kępiński, Marian Smoluchowski, and Kazimierz Twardowski. He passed the teachers exam in 1903 and received a government scholarship in 1906 to study at the University of Göttingen where he attended lectures by David Hilbert, Felix Klein, H. Minkovsky, and others. He taught at the 7th Gymnasium in Lviv and from 1913 at the Lviv Polytechnic School. In 1918-19 he took part in the Polish-Ukrainian war. In 1920 he became professor of the Lwów University of Technology and taught for the next twenty years. He was part of the Lwów school of mathematics and influenced many other mathematicians including Stefan Banach, Kazimierz Kuratowski, Stanisław Stożek, Antoni Nikliborc, Stefan Kaczmarz, Władysław Orlicz, and Stanisław Mazur. In 1938 he became a member of the Warsaw Scientific Society (TNW). He worked on probability, calculus, statistics and mathematical cartography and wrote on the teaching of mathematics. His major works included Kartografia matematyczna (Warszawa 1927).Łomnicki was ar
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https://en.wikipedia.org/wiki/Herman%20Auerbach
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Herman Auerbach (October 26, 1901, Tarnopol – August 17, 1942) was a Polish mathematician and member of the Lwów School of Mathematics.
Auerbach was professor at Lwów University. During the Second World War because of his Jewish descent he was imprisoned by the Germans in the Lwów ghetto. In 1942 he was murdered at Bełżec extermination camp.
See also
Jewish ghettos in German-occupied Poland
List of Nazi-German concentration camps
The Holocaust in Poland
World War II casualties of Poland
References
External links
Author profile in the database zbMATH
1901 births
1942 deaths
People from Ternopil
People from the Kingdom of Galicia and Lodomeria
Jews from Galicia (Eastern Europe)
Austro-Hungarian Jews
Lwów School of Mathematics
Lwów Ghetto inmates
People who died in Belzec extermination camp
Polish civilians killed in World War II
Polish people who died in Nazi concentration camps
Polish Jews who died in the Holocaust
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https://en.wikipedia.org/wiki/148%20%28number%29
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148 (one hundred [and] forty-eight) is the natural number following 147 and before 149.
In mathematics
148 is the second number to be both a heptagonal number and a centered heptagonal number (the first is 1). It is the twelfth member of the Mian–Chowla sequence, the lexicographically smallest sequence of distinct positive integers with distinct pairwise sums.
There are 148 perfect graphs with six vertices, and 148 ways of partitioning four people into subsets, ordering the subsets, and selecting a leader for each subset.
In other fields
In the Book of Nehemiah 7:44 there are 148 singers, sons of Asaph, at the census of men of Israel upon return from exile. This differs from Ezra 2:41, where the number is given as 128.
Dunbar's number is a theoretical cognitive limit to the number of people with whom one can maintain stable interpersonal relationships. Dunbar predicted a "mean group size" of 148, but this is commonly rounded to 150.
See also
The year AD 148 or 148 BC
List of highways numbered 148
References
Integers
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https://en.wikipedia.org/wiki/F-coalgebra
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In mathematics, specifically in category theory, an -coalgebra is a structure defined according to a functor , with specific properties as defined below. For both algebras and coalgebras, a functor is a convenient and general way of organizing a signature. This has applications in computer science: examples of coalgebras include lazy evaluation, infinite data structures, such as streams, and also transition systems.
-coalgebras are dual to -algebras. Just as the class of all algebras for a given signature and equational theory form a variety, so does the class of all -coalgebras satisfying a given equational theory form a covariety, where the signature is given by .
Definition
Let
be an endofunctor on a category .
An -coalgebra is an object of together with a morphism
of , usually written as .
An -coalgebra homomorphism from to another -coalgebra
is a morphism
in such that
.
Thus the -coalgebras for a given functor F constitute a category.
Examples
Consider the endofunctor that sends a set to its disjoint union with the singleton set . A coalgebra of this endofunctor is given by , where is the so-called conatural numbers, consisting of the nonnegative integers and also infinity, and the function is given by , for and . In fact, is the terminal coalgebra of this endofunctor.
More generally, fix some set , and consider the functor that sends to . Then an -coalgebra is a finite or infinite stream over the alphabet where is the set of stat
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https://en.wikipedia.org/wiki/TCC
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TCC may refer to:
Companies
Taiwan Cement Corporation
The Casual Courier
The Clearing Corporation
Trammell Crow Company
Travancore Cochin Chemicals, Kochi, Kerala, India
Organizations
Tanana Chiefs Conference
Theory of Cryptography Conference
Technology and Construction Court
Texas Cave Conservancy
Texas Cryptologic Center
Toronto Congress Centre
Travelers' Century Club
Tri-County Conference (disambiguation)
True Catholic Church
Tucson Convention Center
Tunisian Community Center
Tysons Corner Center
The Carter Center
Colleges and education
Tacoma Community College
Tallahassee Community College
Tarrant County College
Taught Course Centre
Texas Chiropractic College
Tidewater Community College
Torpoint Community College
Traverse City Central High School
Trinity Catholic College, Lismore
Trinity Christian College
Trinity College, Cambridge
Tulsa Community College
Science, technology, and medicine
Terminal complement complex, the membrane attack complex of the complement system
Thermomechanical Cuttings Cleaner
Total contact casting, a specially designed cast designed to take weight of the foot
Torque converter clutch
Transitional cell carcinoma, which affects the bladder
Trewartha climate classification, a climate classification system
Triclocarban, a disinfectant
TCC, a codon for the amino acid serine
Computing
Take Command Console, a command line interpreter by JP Software
Tiny C Compiler, a C compiler
Music and entertainment
The Catholic Channel
The Children's Ch
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https://en.wikipedia.org/wiki/Gigantothermy
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Gigantothermy (sometimes called ectothermic homeothermy or inertial homeothermy) is a phenomenon with significance in biology and paleontology, whereby large, bulky ectothermic animals are more easily able to maintain a constant, relatively high body temperature than smaller animals by virtue of their smaller surface-area-to-volume ratio. A bigger animal has proportionately less of its body close to the outside environment than a smaller animal of otherwise similar shape, and so it gains heat from, or loses heat to, the environment much more slowly.
The phenomenon is important in the biology of ectothermic megafauna, such as large turtles, and aquatic reptiles like ichthyosaurs and mosasaurs. Gigantotherms, though almost always ectothermic, generally have a body temperature similar to that of endotherms. It has been suggested that the larger dinosaurs would have been gigantothermic, rendering them virtually homeothermic.
Disadvantages
Gigantothermy allows animals to maintain body temperature, but is most likely detrimental to endurance and muscle power as compared with endotherms due to decreased anaerobic efficiency. Mammals' bodies have roughly four times as much surface area occupied by mitochondria as reptiles, necessitating larger energy demands, and consequently producing more heat to use in thermoregulation. An ectotherm the same size of an endotherm would not be able to remain as active as the endotherm, as heat is modulated behaviorally rather than biochemically.
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https://en.wikipedia.org/wiki/Martian%20scientist
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A Martian scientist or Martian researcher is a hypothetical Martian frequently used in thought experiments as an outside observer of conditions on Earth. The most common variety is the Martian anthropologist, but Martians researching subjects such as philosophy, linguistics and biology have also been invoked.
The following extract from an essay by Richard Dawkins is more or less typical.
A Martian taxonomist who didn't know that all human races happily interbreed with one another, and didn't know that most of the underlying genetic variance in our species is shared by all races might be tempted by our regional differences in skin colour, facial features, hair, body size and proportions to split us into more than one species.
In American structuralist linguistics, the Martian approach is recommended for language description:
The descriptive analyst must be guided by certain very fixed principles if he is to be objective in describing accurately any language or part of any language. It would be excellent if he could adopt a completely man-from-Mars attitude toward any language he analyzes and describes.
The hypothetical Martian anthropologist is described in the writings of Noam Chomsky as one who, upon studying the world's languages, would conclude that they are all dialects of a single language embodying a "universal grammar" reflecting a hardwired, genetically determined linguistic module inherent in the human brain.
In philosophy, especially philosophy of language and p
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https://en.wikipedia.org/wiki/Adiabatic%20shear%20band
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In physics, mechanics and engineering, an adiabatic shear band is one of the many mechanisms of failure that occur in metals and other materials that are deformed at a high rate in processes such as metal forming, machining and ballistic impact. Adiabatic shear bands are usually very narrow bands, typically 5-500 μm wide and consisting of highly sheared material. Adiabatic is a thermodynamic term meaning an absence of heat transfer – the heat produced is retained in the zone where it is created. (The opposite extreme, where all heat that is produced is conducted away, is isothermal.)
Deformation
It is necessary to include some basics of plastic deformation to understand the link between heat produced and the plastic work done. If we carry out a compression test on a cylindrical specimen to, say, 50% of its original height, the stress of the work material will increase usually significantly with reduction. This is called ‘work hardening’. During work hardening, the micro-structure, distortion of grain structure and the generation and glide of dislocations all occur. The remainder of the plastic work done – which can be as much as 90% of the total, is dissipated as heat.
If the plastic deformation is carried out under dynamic conditions, such as by drop forging, then the plastic deformation is localized more as the forging hammer speed is increased. This also means that the deformed material becomes hotter the higher the speed of the drop hammer. Now as metals become warmer,
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https://en.wikipedia.org/wiki/Gelfond%27s%20constant
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In mathematics, Gelfond's constant, named after Aleksandr Gelfond, is , that is, raised to the power . Like both and , this constant is a transcendental number. This was first established by Gelfond and may now be considered as an application of the Gelfond–Schneider theorem, noting that
where is the imaginary unit. Since is algebraic but not rational, is transcendental. The constant was mentioned in Hilbert's seventh problem. A related constant is , known as the Gelfond–Schneider constant. The related value + is also irrational.
Numerical value
The decimal expansion of Gelfond's constant begins
...
Construction
If one defines and
for , then the sequence
converges rapidly to .
Continued fraction expansion
This is based on the digits for the simple continued fraction:
As given by the integer sequence A058287.
Geometric property
The volume of the n-dimensional ball (or n-ball), is given by
where is its radius, and is the gamma function. Any even-dimensional ball has volume
and, summing up all the unit-ball () volumes of even-dimension gives
Similar or related constants
Ramanujan's constant
This is known as Ramanujan's constant. It is an application of Heegner numbers, where 163 is the Heegner number in question.
Similar to , is very close to an integer:
...
This number was discovered in 1859 by the mathematician Charles Hermite.
In a 1975 April Fool article in Scientific American magazine, "Mathematical Games" columnist Martin Gardner made th
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https://en.wikipedia.org/wiki/Technical%20High%20School%20of%20Limeira
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The Technical High School of Limeira (Portuguese: Colégio Técnico de Limeira, COTIL) is a public high school maintained by the State University of Campinas. Its campus is located in Limeira, São Paulo, Brazil. The school was founded in 1967.
COTIL provides courses in computer science, mechanical engineering, nursing, civil engineering, geomatics, and quality & productivity.
External links
COTIL webpage
UNICAMP webpage
Schools in Brazil
University of Campinas
Limeira
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https://en.wikipedia.org/wiki/Elizabeth%20Fama
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Elizabeth Fama is a young adult author, best known for her book Monstrous Beauty (Farrar, Straus and Giroux Books for Young Readers, 2012), a fantasy novel for teens. Her third book is Plus One, which published in April 2014.
Background
Elizabeth attended University of Chicago Laboratory Schools. She has a BA (1985) in biology with honors from the University of Chicago, and an MBA (1991) and PhD (1996) in economics and finance from the University of Chicago Graduate School of Business.
Elizabeth is the daughter of Eugene Fama. She is married to John H. Cochrane and together, they have four children.
Works
Overboard, Cricket Books, Chicago (2002)
Men Who Wish To Drown (e-book), Tor.com, New York (2012)
Monstrous Beauty, Farrar Straus Giroux, New York (2012)
Noma Girl, Tor·Com, New York (2014)
Plus One, Farrar Straus Giroux, New York (2014)
Reception
Fama's works have generally been well received. Kirkus Reviews wrote about Overboard, "Although some scenes seem implausible, particularly Emily’s ability to carry on complete conversations and sing in her weakened state, first-time author Fama skillfully conveys the impact of survival in human nature" and "Inspired by an actual ferry accident caused by lax safety standards, this is a powerful exploration on the will to live", while Publishers Weekly asserted "Such muddled, cumbersome prose weighs down the chronicle of Emily's nightlong struggle to survive in the sea, heavily reliant upon coincidences."
Kirkus was also
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https://en.wikipedia.org/wiki/Symbolic%20dynamics
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In mathematics, symbolic dynamics is the practice of modeling a topological or smooth dynamical system by a discrete space consisting of infinite sequences of abstract symbols, each of which corresponds to a state of the system, with the dynamics (evolution) given by the shift operator. Formally, a Markov partition is used to provide a finite cover for the smooth system; each set of the cover is associated with a single symbol, and the sequences of symbols result as a trajectory of the system moves from one covering set to another.
History
The idea goes back to Jacques Hadamard's 1898 paper on the geodesics on surfaces of negative curvature. It was applied by Marston Morse in 1921 to the construction of a nonperiodic recurrent geodesic. Related work was done by Emil Artin in 1924 (for the system now called Artin billiard), Pekka Myrberg, Paul Koebe, Jakob Nielsen, G. A. Hedlund.
The first formal treatment was developed by Morse and Hedlund in their 1938 paper. George Birkhoff, Norman Levinson and the pair Mary Cartwright and J. E. Littlewood have applied similar methods to qualitative analysis of nonautonomous second order differential equations.
Claude Shannon used symbolic sequences and shifts of finite type in his 1948 paper A mathematical theory of communication that gave birth to information theory.
During the late 1960s the method of symbolic dynamics was developed to hyperbolic toral automorphisms by Roy Adler and Benjamin Weiss, and to Anosov diffeomorphisms by Y
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https://en.wikipedia.org/wiki/Subshift%20of%20finite%20type
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In mathematics, subshifts of finite type are used to model dynamical systems, and in particular are the objects of study in symbolic dynamics and ergodic theory. They also describe the set of all possible sequences executed by a finite state machine. The most widely studied shift spaces are the subshifts of finite type.
Definition
Let be a finite set of symbols (alphabet). Let denote the set of all bi-infinite sequences of elements of together with the shift operator . We endow with the discrete topology and with the product topology. A symbolic flow or subshift is a closed -invariant subset of and the associated language is the set of finite subsequences of .
Now let be an adjacency matrix with entries in Using these elements we construct a directed graph with the set of vertices and the set of edges containing the directed edge in if and only if . Let be the set of all infinite admissible sequences of edges, where by admissible it is meant that the sequence is a walk of the graph, and the sequence can be either one-sided or two-sided infinite. Let be the left shift operator on such sequences; it plays the role of the time-evolution operator of the dynamical system. A subshift of finite type is then defined as a pair obtained in this way. If the sequence extends to infinity in only one direction, it is called a one-sided subshift of finite type, and if it is bilateral, it is called a two-sided subshift of finite type.
Formally, one may define
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https://en.wikipedia.org/wiki/EMD%20SD38-2
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The EMD SD38-2 is a model of six-axle diesel-electric locomotive built by General Motors Electro-Motive Division (EMD) from 1972 to 1979. EMD built 90 of these medium road-switchers, which were used in both yard and mainline roles. Part of the EMD Dash 2 line, the SD38-2 was an upgraded SD38 with modular electronic control systems, HT-C trucks, and many other detail improvements. The locomotive's power was provided by an EMD 16-645E 16-cylinder engine, which could generate . These units were constructed with either fuel tanks and were available with or without dynamic brakes. It shared the same frame as the SD40-2 and SD45-2, which gives it a length over couplers of .
Original owners
See also
List of GM-EMD locomotives
List of GMD Locomotives
References
GATX Rail Locomotive Group. SD38-2 specification page. Retrieved on June 23, 2005.
Sarberenyi, Robert. EMD SD38-2 Original Owners
EMD SD38-2 general arrangement drawing (Spec. 8086 07/75) and clearance diagram (04/72), Robb Fisher, RFDI.
External links
Sarberenyi, Robert. EMD SD38-2 Original Owners
SD38-2
SD38-2
C-C locomotives
Diesel-electric locomotives of the United States
Railway locomotives introduced in 1972
Freight locomotives
Standard gauge locomotives of the United States
5 ft 3 in gauge locomotives
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https://en.wikipedia.org/wiki/Black%20hole%20electron
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In physics, there is a speculative hypothesis that, if there were a black hole with the same mass, charge and angular momentum as an electron, it would share other properties of the electron. Most notably, Brandon Carter showed in 1968 that the magnetic moment of such an object would match that of an electron. This is interesting because calculations ignoring special relativity and treating the electron as a small rotating sphere of charge give a magnetic moment roughly half the experimental value (see Gyromagnetic ratio).
However, Carter's calculations also show that a would-be black hole with these parameters would be "super-extremal". Thus, unlike a true black hole, this object would display a naked singularity, meaning a singularity in spacetime not hidden behind an event horizon. It would also give rise to closed timelike curves.
Standard quantum electrodynamics (QED), currently the most comprehensive theory of particles, treats the electron as a point particle. There is no evidence that the electron is a black hole (or naked singularity) or not. Furthermore, since the electron is quantum-mechanical in nature, any description purely in terms of general relativity is paradoxical until a better model based on understanding of quantum nature of blackholes and gravitational behaviour of quantum particles is developed by research. Hence, the idea of a black hole electron remains strictly hypothetical.
Details
An article published in 1938 by Albert Einstein, Leopold Infeld,
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https://en.wikipedia.org/wiki/Shaft%20sinking
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Shaft mining or shaft sinking is the action of excavating a mine shaft from the top down, where there is initially no access to the bottom. Shallow shafts, typically sunk for civil engineering projects, differ greatly in execution method from deep shafts, typically sunk for mining projects.
Shaft sinking is one of the most difficult of all mine development methods: restricted space, gravity, groundwater and specialized procedures make the task quite formidable. Shafts may be sunk by conventional drill and blast or mechanised means.
Historically, mine shaft sinking has been among the most dangerous of all the mining occupations and the preserve of mining contractors called sinkers. Today shaft sinking contractors are concentrated in Canada, Germany, China and South Africa.
The modern shaft sinking industry is gradually shifting further towards greater mechanisation. Recent innovations in the form of full-face shaft boring (akin to a vertical tunnel boring machine) have shown promise but the use of this method is, as of 2019, not widespread.
Mine shafts
Mine shafts are vertical or near-vertical tunnels, which are "sunk" as a means of accessing an underground ore body, during the development of an underground mine.
The shape (in plan view), dimensions and depth of mine shafts vary greatly in response to the specific needs of the mine they are part of and the geology they are sunk through. For example, in North and South America, smaller shafts are designed to be rectangula
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https://en.wikipedia.org/wiki/Supercluster%20%28genetic%29
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Most usage of supercluster in population genetics research articles applies to proposed large groups of human mtDNA haplotype lineages, found by cluster analysis, that are thought to stem from a single distant most recent common ancestor, on a time scale of tens of thousands of years.
Other usage
Usage of supercluster for geographically defined human populations instead of mtDNA strains is rarely seen. However, it does appear in the seminal Cavalli-Sforza paper
Reconstruction of human evolution: bringing together genetic, archaeological, and linguistic data. (1988) to describe "Northeurasian" and "Southeast Asian" collections of sampled populations, which are also more frequently referred to in the paper as "major cluster" or simply "cluster".
Therefore use of "supercluster" as a euphemism for "race" might be considered a neologism or, more likely, an idiosyncratic usage according to the Google test.
Usage of supercluster for populations as well as haplotypes makes the term ambiguous and may require clarification when the word is used.
External links
Examples of usage to describe haplogroups, not races:
The sub-Saharan African mtDNAs belong largely to an mtDNA supercluster L
More than 90% of European mtDNAs belong to nine haplogroups (Fig. 1), which are highly specific for Western Eurasia (4, 6). These clusters are all thought to originate from one supercluster, L3n (N).
The main determinants of this PC analysis are therefore the HV supercluster members, haplogroups H
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https://en.wikipedia.org/wiki/Marcel%20J.%20E.%20Golay
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Marcel Jules Edouard Golay (; May 3, 1902 – April 27, 1989) was a Swiss mathematician, physicist, and information theorist, who applied mathematics to real-world military and industrial problems. He was born in Neuchâtel, Switzerland.
Career
Golay studied electrical engineering at the Eidgenössische Technische Hochschule (Swiss Federal Institute of Technology) in Zürich. He joined Bell laboratories in New York City in 1924, spending four years there. He received a Ph.D. in physics from the University of Chicago in 1931.
Golay then joined the US Army Signal Corps, eventually rising to the post of Chief Scientist. He was based mostly in Fort Monmouth, New Jersey. He developed an IR "radar" based on its Golay Detector, the SCR-268T specifically designed to the detection of vessels (S/S Normandie was detected at its inaugural crossing). The SCR-268 (using Barkausen vacuum tubes) and the SCR-268T were to work together. However the 268T, only used in the Pacific theater was abandoned before the end of the war.
Between 1955 and 1963, Golay was a consultant for Philco Corporation of Philadelphia, PA, and the Perkin-Elmer Corporation of Norwalk, Connecticut. In 1963, Golay joined the Perkin-Elmer company full-time as senior research scientist. Golay worked on many problems, including gas chromatography and optical spectroscopy. It was during this period when he patented an Analysis of Images, for two-dimensional parallel data processing, and worked to develop the idea, called Gola
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https://en.wikipedia.org/wiki/Zsolt%20Bor
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Zsolt Bor (born 1949) is a Hungarian physicist, currently working at the University of Szeged. He has a BSc in Electrical Engineering from the Technical University in Kiev (1973), an MSc in physics (1974), and PhD in Physics from JATE University (1975). He is a member of the Academia Europaea, the Hungarian Academy of Sciences, the Quantum Electronics and Optics Division of the European Physical Society, the Commission on Quantum Electronics, and Hungarian Physical Society Department of Optics and Quantum Electronics. He is one of the inventors of the Rhinolight phototherapeutical apparatus for hay fever therapy.
References
1949 births
Living people
Members of the Hungarian Academy of Sciences
Academic staff of the University of Szeged
20th-century Hungarian physicists
21st-century Hungarian physicists
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https://en.wikipedia.org/wiki/L%C3%A1szl%C3%B3%20Kalm%C3%A1r
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László Kalmár (27 March 1905, Edde – 2 August 1976, Mátraháza) was a Hungarian mathematician and Professor at the University of Szeged. Kalmár is considered the founder of mathematical logic and theoretical computer science in Hungary.
Biography
Kalmár was of Jewish ancestry. His early life mixed promise and tragedy. His father died when he was young, and his mother died when he was 17, the year he entered the University of Budapest, making him essentially an orphan.
Kalmár's brilliance manifested itself while in Budapest schools. At the University of Budapest, his teachers included Kürschák and Fejér. His fellow students included the future logician Rózsa Péter. Kalmár graduated in 1927. He discovered mathematical logic, his chosen field, while visiting Göttingen in 1929.
Upon completing his doctorate at Budapest, he took up a position at the University of Szeged. That university was mostly made up of staff from the former University of Kolozsvár, a major Hungarian university before World War I that found itself after the War in Romania. Kolozsvár was renamed Cluj. The Hungarian university moved to Szeged in 1920, where there had previously been no university. The appointment of Haar and Riesz turned Szeged into a major research center for mathematics. Kalmár began his career as a research assistant to Haar and Riesz. Kalmár was appointed a full professor at Szeged in 1947. He was the inaugural holder of Szeged's chair for the Foundations of Mathematics and Computer Scien
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https://en.wikipedia.org/wiki/Vesicle
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Vesicle may refer to:
In cellular biology or chemistry
Vesicle (biology and chemistry), a supramolecular assembly of lipid molecules, like a cell membrane
Synaptic vesicle
In human embryology
Vesicle (embryology), bulge-like features of the early neural tube during embryonic brain development
Auditory vesicle
Optic vesicles
In human anatomy and morphology
Seminal vesicle
Vesicle (dermatology), a liquid-filled cavity under the epidermis, commonly called a blister
In non-human morphology
Subsporangial vesicle
Juice vesicles, the pulp found in the endocarp of common citrus members
In geology
Vesicular texture, a small enclosed cavity found in some volcanic rock, such as basalt
See also
Vesical (disambiguation)
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https://en.wikipedia.org/wiki/Jean%20Becquerel
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Jean Antoine Edmond Marie Becquerel (5 February 1878 – 4 July 1953) was a French physicist, the son of Antoine-Henri Becquerel. He worked on a range of experimental physics topics including magnetic effects on the optical properties of materials, and the effects of low-temperature on magnetic susceptibility. He was among the early teachers of relativity and quantum physics in France.
Biography
Becquerel was born at his home in the Jardin des Plantes where his father Henri (1852–1908), grandfather Edmond (1820–1891) and great-grandfather Antoine César Becquerel (1788–1878) had lived. His mother Lucie was the daughter of J.C. Jamin, professor of physics at the Sorbonne. His childhood toys included magnets and electroscopes. He was educated at the Lycée Louis-le-Grand before going to the École Polytechnique in 1897 and completed his studies at the École des Ponts et Chaussées.
He then became an assistant in physics at the Museum of Natural History. He worked on the optical and magnetic properties of crystals, and continued experiments to study changes in rotational polarisation induced by a magnetic field that his father had discovered. He also published a textbook on relativity In 1903 some of his research came into question when he collaborated with surgeon André Broca to examine the radiation (N-Rays) supposedly emanating from living bodies (as claimed originally by René Blondlot) which was claimed to reduce upon the administration of anaesthetics.
In 1909, he became the
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https://en.wikipedia.org/wiki/Indeterminate%20growth
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In biology and botany, indeterminate growth is growth that is not terminated in contrast to determinate growth that stops once a genetically pre-determined structure has completely formed. Thus, a plant that grows and produces flowers and fruit until killed by frost or some other external factor is called indeterminate. For example, the term is applied to tomato varieties that grow in a rather gangly fashion, producing fruit throughout the growing season. In contrast, a determinate tomato plant grows in a more bushy shape and is most productive for a single, larger harvest, then either tapers off with minimal new growth or fruit or dies.
Inflorescences
In reference to an inflorescence (a shoot specialised for bearing flowers, and bearing no leaves other than bracts), an indeterminate type (such as a raceme) is one in which the first flowers to develop and open are from the buds at the base, followed progressively by buds nearer to the growing tip. The growth of the shoot is not impeded by the opening of the early flowers or development of fruits and its appearance is of growing, producing, and maturing flowers and fruit indefinitely. In practice the continued growth of the terminal end necessarily peters out sooner or later, though without producing any definite terminal flower, and in some species it may stop growing before any of the buds have opened.
Not all plants produce indeterminate inflorescences however; some produce a definite terminal flower that terminates the
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https://en.wikipedia.org/wiki/Phagosome
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In cell biology, a phagosome is a vesicle formed around a particle engulfed by a phagocyte via phagocytosis. Professional phagocytes include macrophages, neutrophils, and dendritic cells (DCs).
A phagosome is formed by the fusion of the cell membrane around a microorganism, a senescent cell or an apoptotic cell. Phagosomes have membrane-bound proteins to recruit and fuse with lysosomes to form mature phagolysosomes. The lysosomes contain hydrolytic enzymes and reactive oxygen species (ROS) which kill and digest the pathogens. Phagosomes can also form in non-professional phagocytes, but they can only engulf a smaller range of particles, and do not contain ROS. The useful materials (e.g. amino acids) from the digested particles are moved into the cytosol, and waste is removed by exocytosis. Phagosome formation is crucial for tissue homeostasis and both innate and adaptive host defense against pathogens.
However, some bacteria can exploit phagocytosis as an invasion strategy. They either reproduce inside of the phagolysosome (e.g. Coxiella spp.) or escape into the cytoplasm before the phagosome fuses with the lysosome (e.g. Rickettsia spp.). Many Mycobacteria, including Mycobacterium tuberculosis and Mycobacterium avium paratuberculosis, can manipulate the host macrophage to prevent lysosomes from fusing with phagosomes and creating mature phagolysosomes. Such incomplete maturation of the phagosome maintains an environment favorable to the pathogens inside it.
Formation
Pha
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https://en.wikipedia.org/wiki/Ritz%20method
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In the study of differential equations, the Ritz method is a direct method to find an approximate solution for boundary value problems. The method is named after Walther Ritz. It is also commonly called the Rayleigh–Ritz method and the Ritz-Galerkin method.
In quantum mechanics, a system of particles can be described in terms of an "energy functional" or Hamiltonian, which will measure the energy of any proposed configuration of said particles. It turns out that certain privileged configurations are more likely than other configurations, and this has to do with the eigenanalysis ("analysis of characteristics") of this Hamiltonian system. Because it is often impossible to analyze all of the infinite configurations of particles to find the one with the least amount of energy, it becomes essential to be able to approximate this Hamiltonian in some way for the purpose of numerical computations.
The Ritz method can be used to achieve this goal. In the language of mathematics, it is exactly the finite element method used to compute the eigenvectors and eigenvalues of a Hamiltonian system.
Definitions
As with other variational methods, a trial wave function, , is tested on the system. This trial function is selected to meet boundary conditions (and any other physical constraints). The exact function is not known; the trial function contains one or more adjustable parameters, which are varied to find a lowest energy configuration.
It can be shown that the ground state energy
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https://en.wikipedia.org/wiki/Albert%20Schatz%20%28scientist%29
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Albert Israel Schatz (2 February 1920 – 17 January 2005) was an American microbiologist and academic who discovered streptomycin, the first antibiotic known to be effective for the treatment of tuberculosis. He graduated from Rutgers University in 1942 with a bachelor's degree in soil microbiology, and received his doctorate from Rutgers in 1945. His PhD research led directly to the discovery of streptomycin.
Born to a family of farmers, Schatz was inspired to study soil science for its potential applicability to take up his family occupation. Topping his class at Rutgers in 1942, he immediately worked under Selman Waksman, then head of the Department of Soil Microbiology, but was drafted to the US Army to serve in the World War II. After a back injury led to his discharge from the army, he rejoined Waksman in 1943 as a PhD student. Working in isolation from others due to his use of the dreaded tuberculosis bacterium (Mycobacterium tuberculosis), he discovered a new antibiotic which he named "streptomycin" that was proven safe and effective against the tuberculosis bacterium and other bacteria. He also contributed to the discovery another antibiotic albomycin in 1947.
The discovery of streptomycin led to controversies over its royalties from commercial production, and the Nobel Prize. Unbeknownst to Schatz, Waksman had claimed financial benefits only for himself and the Rutgers Research and Endowment Foundation. A lawsuit granted Schatz 3% of the royalties and legal recogni
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https://en.wikipedia.org/wiki/Self-descriptive%20number
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In mathematics, a self-descriptive number is an integer m that in a given base b is b digits long in which each digit d at position n (the most significant digit being at position 0 and the least significant at position b−1) counts how many instances of digit n are in m.
Example
For example, in base 10, the number 6210001000 is self-descriptive because of the following reasons:
In base 10, the number has 10 digits, indicating its base;
It contains 6 at position 0, indicating that there are six 0s in 6210001000;
It contains 2 at position 1, indicating that there are two 1s in 6210001000;
It contains 1 at position 2, indicating that there is one 2 in 6210001000;
It contains 0 at position 3, indicating that there is no 3 in 6210001000;
It contains 0 at position 4, indicating that there is no 4 in 6210001000;
It contains 0 at position 5, indicating that there is no 5 in 6210001000;
It contains 1 at position 6, indicating that there is one 6 in 6210001000;
It contains 0 at position 7, indicating that there is no 7 in 6210001000;
It contains 0 at position 8, indicating that there is no 8 in 6210001000;
It contains 0 at position 9, indicating that there is no 9 in 6210001000.
In different bases
There are no self-descriptive numbers in bases 2, 3 or 6. In bases 7 and above, there is, if nothing else, a self-descriptive number of the form , which has b−4 instances of the digit 0, two instances of the digit 1, one instance of the digit 2, one instance of digit b – 4, and no instance
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https://en.wikipedia.org/wiki/Gam%C4%8Da
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Gamča (), today officially Gymnázium, Grösslingová 18, Bratislava, is a public coeducational gymnasium located in Bratislava, Slovakia. It educates around 600 pupils in 8-year long and 4-year long programs leading to Maturita. It was founded in 1626 by Peter Cardinal Pazmáň (Péter Pázmany) as Collegium Posoniense.
Gamča's focus on mathematics, natural sciences and computer sciences brought 56 of its students to successfully represent Slovakia (Czechoslovakia) at the International Mathematical Olympiad, 26 students at the International Physics Olympiad and 14 at the International Olympiad in Informatics in the past 35 years.
Since 1988, the school's popular "Olympic games", OH Gamča, are held annually.
History
Cardinal Archbishop of Esztergom Petrus Pazmanus founded Collegium Posoniense on September 11, 1626, with the approval of the 6th Jesuit Superior General Mutio Vitelleschi and Ferdinand II, Holy Roman Emperor.
Building
The current building was designed by Ödön Lechner and built in 1906–08. Few years later its "chapel", today known as Church of St. Elisabeth (Bratislava), was added. The school building was completely renovated in 2008–10.
OH Gamča
Olympijské hry Gamča (Gamča's Olympic Games) are held from September to December every year since 1988, when inspired by the 1988 Olympic Games in Seoul the first games were organized to celebrate the 70th anniversary of Czechoslovakia. During the games, classes (i.e. ~30 students, ~4 classes in every year) are competing a
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https://en.wikipedia.org/wiki/Double%20beta%20decay
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In nuclear physics, double beta decay is a type of radioactive decay in which two neutrons are simultaneously transformed into two protons, or vice versa, inside an atomic nucleus. As in single beta decay, this process allows the atom to move closer to the optimal ratio of protons and neutrons. As a result of this transformation, the nucleus emits two detectable beta particles, which are electrons or positrons.
The literature distinguishes between two types of double beta decay: ordinary double beta decay and neutrinoless double beta decay. In ordinary double beta decay, which has been observed in several isotopes, two electrons and two electron antineutrinos are emitted from the decaying nucleus. In neutrinoless double beta decay, a hypothesized process that has never been observed, only electrons would be emitted.
History
The idea of double beta decay was first proposed by Maria Goeppert Mayer in 1935.
In 1937, Ettore Majorana demonstrated that all results of beta decay theory remain unchanged if the neutrino were its own antiparticle, now known as a Majorana particle.
In 1939, Wendell H. Furry proposed that if neutrinos are Majorana particles, then double beta decay can proceed without the emission of any neutrinos, via the process now called neutrinoless double beta decay.
It is not yet known whether the neutrino is a Majorana particle, and, relatedly, whether neutrinoless double beta decay exists in nature.
In 1930–1940s, parity violation in weak interactions was not
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https://en.wikipedia.org/wiki/Normed%20algebra
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In mathematics, a normed algebra A is an algebra over a field which has a sub-multiplicative norm:
Some authors require it to have a multiplicative identity 1 such that ║1║ = 1.
See also
Banach algebra
Composition algebra
Division algebra
Gelfand–Mazur theorem
Hurwitz's theorem (composition algebras)
External reading
Algebras
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https://en.wikipedia.org/wiki/The%20Laws%20of%20Thought
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An Investigation of the Laws of Thought on Which are Founded the Mathematical Theories of Logic and Probabilities by George Boole, published in 1854, is the second of Boole's two monographs on algebraic logic. Boole was a professor of mathematics at what was then Queen's College, Cork (now University College Cork), in Ireland.
Review of the contents
The historian of logic John Corcoran wrote an accessible introduction to Laws of Thought and a point by point comparison of Prior Analytics and Laws of Thought. According to Corcoran, Boole fully accepted and endorsed Aristotle's logic. Boole's goals were “to go under, over, and beyond” Aristotle's logic by:
Providing it with mathematical foundations involving equations;
Extending the class of problems it could treat from assessing validity to solving equations, and;
Expanding the range of applications it could handle — e.g. from propositions having only two terms to those having arbitrarily many.
More specifically, Boole agreed with what Aristotle said; Boole's ‘disagreements’, if they might be called that, concern what Aristotle did not say. First, in the realm of foundations, Boole reduced the four propositional forms of Aristotle's logic to formulas in the form of equations—by itself a revolutionary idea. Second, in the realm of logic's problems, Boole's addition of equation solving to logic—another revolutionary idea—involved Boole's doctrine that Aristotle's rules of inference (the “perfect syllogisms”) must be su
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https://en.wikipedia.org/wiki/International%20Chemical%20Identifier
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The International Chemical Identifier (InChI or ) is a textual identifier for chemical substances, designed to provide a standard way to encode molecular information and to facilitate the search for such information in databases and on the web. Initially developed by the International Union of Pure and Applied Chemistry (IUPAC) and National Institute of Standards and Technology (NIST) from 2000 to 2005, the format and algorithms are non-proprietary. Since May 2009, it has been developed by the InChI Trust, a nonprofit charity from the United Kingdom which works to implement and promote the use of InChI.
The identifiers describe chemical substances in terms of layers of information — the atoms and their bond connectivity, tautomeric information, isotope information, stereochemistry, and electronic charge information.
Not all layers have to be provided; for instance, the tautomer layer can be omitted if that type of information is not relevant to the particular application. The InChI algorithm converts input structural information into a unique InChI identifier in a three-step process: normalization (to remove redundant information), canonicalization (to generate a unique number label for each atom), and serialization (to give a string of characters).
InChIs differ from the widely used CAS registry numbers in three respects: firstly, they are freely usable and non-proprietary; secondly, they can be computed from structural information and do not have to be assigned by some
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https://en.wikipedia.org/wiki/Howard%20Davis%20%28professor%20of%20architecture%29
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Howard Davis is an American writer and professor of architecture at the University of Oregon in Eugene. A native of New York City, he studied physics at Cooper Union and at Northwestern University and received a master's degree in architecture from the University of California, Berkeley, where he worked with Christopher Alexander. He has worked on projects in the Pacific Northwest, India, England, Mexico and Israel.
He is known for his research into vernacular architecture and building history, published in the book The Culture of Building (1999, reprinted in paperback 2006). He also collaborated with Christopher Alexander on The Production of Houses (1985), an account of an innovative housing project in Mexicali, Baja California, Mexico. His current research is concerned with urban buildings that combine commercial and residential uses; museums and memorials to war; housing; and American architectural education. His latest book is "Living Over the Store: Architecture and Local Urban Life." Davis was founding co-editor of Buildings & Landscapes, the journal of the Vernacular Architecture Forum.
The Association of Collegiate Schools of Architecture honored Davis with the ACSA Distinguished Professor Award in 2009.
References
External links
What is the Culture of Building? Article from ArchitectureWeek
Year of birth missing (living people)
Living people
Cooper Union alumni
Northwestern University alumni
UC Berkeley College of Environmental Design alumni
American architect
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https://en.wikipedia.org/wiki/Thermalisation
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In physics, thermalisation (or thermalization) is the process of physical bodies reaching thermal equilibrium through mutual interaction. In general the natural tendency of a system is towards a state of equipartition of energy and uniform temperature that maximizes the system's entropy. Thermalisation, thermal equilibrium, and temperature are therefore important fundamental concepts within statistical physics, statistical mechanics, and thermodynamics; all of which are a basis for many other specific fields of scientific understanding and engineering application.
Examples of thermalisation include:
the achievement of equilibrium in a plasma.
the process undergone by high-energy neutrons as they lose energy by collision with a moderator.
the process of heat or phonon emission by charge carriers in a solar cell, after a photon that exceeds the semiconductor band gap energy is absorbed.
The hypothesis, foundational to most introductory textbooks treating quantum statistical mechanics, assumes that systems go to thermal equilibrium (thermalisation). The process of thermalisation erases local memory of the initial conditions. The eigenstate thermalisation hypothesis is a hypothesis about when quantum states will undergo thermalisation and why.
Not all quantum states undergo thermalisation. Some states have been discovered which do not (see below), and their reasons for not reaching thermal equilibrium are unclear .
Theoretical description
The process of equilibration can
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https://en.wikipedia.org/wiki/Grain%20boundary
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In materials science, a grain boundary is the interface between two grains, or crystallites, in a polycrystalline material. Grain boundaries are two-dimensional defects in the crystal structure, and tend to decrease the electrical and thermal conductivity of the material. Most grain boundaries are preferred sites for the onset of corrosion and for the precipitation of new phases from the solid. They are also important to many of the mechanisms of creep. On the other hand, grain boundaries disrupt the motion of dislocations through a material, so reducing crystallite size is a common way to improve mechanical strength, as described by the Hall–Petch relationship.
High and low angle boundaries
It is convenient to categorize grain boundaries according to the extent of misorientation between the two grains. Low-angle grain boundaries (LAGB) or subgrain boundaries are those with a misorientation less than about 15 degrees. Generally speaking they are composed of an array of dislocations and their properties and structure are a function of the misorientation. In contrast the properties of high-angle grain boundaries, whose misorientation is greater than about 15 degrees (the transition angle varies from 10–15 degrees depending on the material), are normally found to be independent of the misorientation. However, there are 'special boundaries' at particular orientations whose interfacial energies are markedly lower than those of general high-angle grain boundaries.
The simplest
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https://en.wikipedia.org/wiki/Johann%20Heinrich%20Schulze
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Johann Heinrich Schulze (12 May 1687 – 10 October 1744) was a German professor and polymath.
History
Schulze studied medicine, chemistry, philosophy and theology and became a professor in Altdorf and Halle for anatomy and several other subjects.
Notable discoveries
Schulze is best known for his discovery that the darkening in sunlight of various substances mixed with silver nitrate is due to the light, not the heat as other experimenters believed, and for using the phenomenon to temporarily capture shadows.
Schulze's experiments with silver nitrate were undertaken in about 1717. He found that a slurry of chalk and nitric acid into which some silver had been dissolved was darkened by sunlight, but not by exposure to the heat from a fire. To provide an interesting demonstration of its darkening by light, he applied stencils of words to a bottle filled with the mixture and put it in direct sunlight, which produced copies of the text in dark characters on the surface of the contents. The impressions persisted until they were erased by shaking the bottle or until overall exposure to light obliterated them. Because they were produced by the action of light, an extremely broad and literal definition of what a photograph is may allow even these fluid, ephemeral sun printings to qualify as such, and on that basis many German sources credit Schulze as the inventor of photography.
Though Schulze's work did not provide a means of permanently preserving an image, it did provide a fou
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https://en.wikipedia.org/wiki/F%C3%A9lix%20Vicq-d%27Azyr
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Félix Vicq d'Azyr (; 23 April 1748 – 20 June 1794) was a French physician and anatomist, the originator of comparative anatomy and discoverer of the theory of homology in biology.
Biography
Vicq d'Azyr was born in Valognes, Normandy, the son of a physician. He graduated in medicine at the University of Paris and became a renowned and brilliant animal and human anatomist and physician.
From 1773 Vicq d'Azyr taught a celebrated course of anatomy at the Jardin du Roi, currently the Museum of Natural History, in Paris. In 1774 he was elected a member of the Académie des Sciences with the support of his friend Condorcet, the Perpetual Secretary. In this latter capacity, he was in charge of writing the eulogies of his colleagues. This he accomplished with great talent, thus winning a lifetime membership to the Académie française in 1788. On the outbreak of an epidemic in Guyenne he was charged with writing a report, of making propositions and with their execution. Pursuing an early perception of the responsibility of the State on health affairs, Anne-Robert-Jacques Turgot proposed the creation of the Société Royale de Médecine. In 1775, Vicq d'Azyr was made Perpetual Secretary. Under his leadership, the Société compiled over 16 years a great mass of facts and information about diseases, physicians, economics and food resources.
He was the last physician of Queen Marie-Antoinette, whom he tried to protect.
Additionally he was a professor of veterinary medicine at the School of
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https://en.wikipedia.org/wiki/Clifton%20Hillegass
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Clifton K. Hillegass (18 April 1918 in Rising City, Nebraska – 5 May 2001 in Lincoln, Nebraska) was the creator and publisher of CliffsNotes.
Biography
Clifton Hillegass graduated from Midland Lutheran College and then studied physics and geology for two years at the University of Nebraska. He later received four honorary degrees.
CliffsNotes began in 1958 as $1 reprints of Canadian study guides for 16 plays by Shakespeare. At that time, Hillegass worked for a major distributor of college textbooks. He knew hundreds of campus bookstore managers across the country. Those close relationships gave him the first outlets for the Notes. Sales expanded rapidly as high school students began to buy the slim yellow and black pamphlets. By the early 1970s the company had created additional study aids—exam reviews, course outlines, law school materials, and test preparation kits for the SAT, ACT, GRE, and GMAT.
As the company grew, Hillegass kept its headquarters in Lincoln, Nebraska. Each year he donated 10 percent of the pre-tax profits to local charities and civic organizations (which, on his death, received half of his estate). Most employees were lifetime Lincoln residents. After he sold the company in 1999, Hillegass endowed a chair in English at the University of Nebraska.
References
Further reading
Robert L. Hampel, Fast and Curious: A History of Shortcuts in American Education (Rowman and Littlefield: Lanham MD, 2017), Ch. 2.
1918 births
2001 deaths
People from B
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https://en.wikipedia.org/wiki/Roger%20Gaudry
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Roger Gaudry, (December 15, 1913 – October 7, 2001) was a Canadian chemist, businessman, corporate director, and rector of the Université de Montréal.
Early life and education
Born in Quebec City, Quebec, he received a Bachelor of Science (B.Sc.) in chemistry in 1937 and a Doctor of Science (D.Sc.) in chemistry in 1940 from Université Laval. A Rhodes scholar, he attended the University of Oxford from 1937 to 1939.
Career
From 1940 to 1945, he was assistant professor of chemistry in the Faculty of Medicine at Université Laval. He was appointed associate professor in 1945 and professor in 1950.
In 1954, he became assistant director of research at Ayerst, McKenna & Harrison Ltd. in Montréal From 1957 to 1965, he was director and vice-president from 1963 to 1965. From 1965 to 1975, he served as the rector of the Université de Montréal.
He was a member of the board of directors of the following companies: Connaught Laboratories Ltd., CDC Life Sciences Inc., Bank of Montreal, Alcan, Hoechst Canada, S.K.W. Canada Ltd., Bio-Recherche Ltée, Corby Distilleries Ltd, and St. Lawrence Starch Co. Ltd.
From 1983 to 1995, he was president of the Fondation Jules et Paul-Emile Léger, a Canadian charity which supports groups that help restore human dignity to those who have been rejected by society.
After his death in 2001, he was entombed at the Notre Dame des Neiges Cemetery in Montreal.
Honours
In 1954, he was made a Fellow of the Royal Society of Canada.
In 1968, he was made a
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https://en.wikipedia.org/wiki/Walter%20Scott%20Jr.
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Walter Scott Jr. (May 21, 1931 – September 25, 2021) was an American billionaire businessman, civil engineer, philanthropist, and CEO of Kiewit Corporation. At the time of his death, his net worth was estimated at US$4.2 billion.
Education
He graduated from Colorado State University in 1953 with a bachelor's degree in civil engineering.
Career
Scott was first elected to the Kiewit Corporation board in 1964. In 1979, he was elected president. When Peter Kiewit died later that same year, Scott was selected to succeed him as chairman.
He sat on the board of Berkshire Hathaway, and was a childhood friend of Warren Buffett. He was also on the board of directors of Burlington Resources, Commonwealth Telephone Enterprises, Level 3 Communications Inc., MidAmerican Energy Holdings, RCN Corporation, Valmont Industries, and Peter Kiewit Sons' Inc, and was the chairman of the Open World Leadership Center at the Library of Congress.
He was a director of the Joslyn Art Museum, Nebraska Game and Parks Foundation, and the Omaha Development Foundation. Nationally, he was a director of the Horatio Alger Association and the National Forest Association.
Scott was chairman of Level 3 Communications.
Philanthropy
Scott consistently ranked among the wealthiest Americans. With his wife, Suzanne, he founded the public, non-profit Suzanne and Walter Scott Foundation which has funded the Scott Atrium & Education Center at University of Nebraska Medical Center, the Scott Technology Center in Omah
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https://en.wikipedia.org/wiki/Robert%20Hoehl
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Robert "Bob" Hoehl (December 13, 1941 – November 7, 2010) was a co-founder of the software company IDX Systems and a Vermont philanthropist.
Born in Brooklyn, NY, Hoehl earned a basketball scholarship to Saint Michael's College in Colchester, Vermont, where he graduated in 1963 with a degree in mathematics. After working at IBM as a computer programmer, he founded Burlington Data Processing (BDP) in 1969 with Richard Tarrant. BDP ultimately changed its name to IDX Systems Corporation and became a leading provider of software to the health care industry. GE Healthcare purchased IDX in 2005 for $1.2 billion.
Hoehl and his wife Cynthia have supported many Vermont organizations, including Community Health Center of Burlington, Preservation Trust of Vermont, Newman Catholic Center at the University of Vermont, Lake Champlain Basin Science Center, Saint Michael's College, the Stern Center for Language and Learning the Boys and Girls Club, and Vermont's United Way. The Hoehls also funded the Hoehl Welcome Center at Saint Michael's College.
Hoehl died at his home in Ferrisburgh, Vermont in 2010 after a six-week hospitalization. He was married to Cynthia Hoehl (died 2016), who also had engaged in philanthropic work in Vermont.
References
1941 births
2010 deaths
American businesspeople
IBM employees
People from Burlington, Vermont
People from Naples, Florida
Saint Michael's Purple Knights men's basketball players
Catholics from Florida
Catholics from Vermont
20th-century American
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https://en.wikipedia.org/wiki/Microtubule-associated%20protein
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In cell biology, microtubule-associated proteins (MAPs) are proteins that interact with the microtubules of the cellular cytoskeleton. MAPs are integral to the stability of the cell and its internal structures and the transport of components within the cell.
Function
MAPs bind to the tubulin subunits that make up microtubules to regulate their stability. A large variety of MAPs have been identified in many different cell types, and they have been found to carry out a wide range of functions. These include both stabilizing and destabilizing microtubules, guiding microtubules towards specific cellular locations, cross-linking microtubules and mediating the interactions of microtubules with other proteins in the cell.
Within the cell, MAPs bind directly to the tubulin dimers of microtubules. This binding can occur with either polymerized or depolymerized tubulin, and in most cases leads to the stabilization of microtubule structure, further encouraging polymerization. Usually, it is the C-terminal domain of the MAP that interacts with tubulin, while the N-terminal domain can bind with cellular vesicles, intermediate filaments or other microtubules. MAP-microtubule binding is regulated through MAP phosphorylation. This is accomplished through the function of the microtubule-affinity-regulating-kinase (MARK) protein. Phosphorylation of the MAP by the MARK causes the MAP to detach from any bound microtubules. This detachment is usually associated with a destabilization of the mic
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https://en.wikipedia.org/wiki/Polytypic
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Polytypic means of more than one type. It often refers to:
Polytypic function, in computer science
Polytypic habitat, in ecology, a habitat not dominated by a single species
Polytypic taxon, in biology, a taxon with more than one immediately subordinate taxa
See also
Polyclonal antibodies
Polytypes in crystallography
Race (classification of human beings) for a discussion of whether the species Homo sapiens is polytypic
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https://en.wikipedia.org/wiki/Paleogenetics
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Paleogenetics is the study of the past through the examination of preserved genetic material from the remains of ancient organisms. Emile Zuckerkandl and Linus Pauling introduced the term in 1963, long before the sequencing of DNA, in reference to the possible reconstruction of the corresponding polypeptide sequences of past organisms. The first sequence of ancient DNA, isolated from a museum specimen of the extinct quagga, was published in 1984 by a team led by Allan Wilson.
Paleogeneticists do not recreate actual organisms, but piece together ancient DNA sequences using various analytical methods. Fossils are "the only direct witnesses of extinct species and of evolutionary events" and finding DNA within those fossils exposes tremendously more information about these species, potentially their entire physiology and anatomy.
The most ancient DNA sequence to date was reported in February 2021, from the tooth of a Siberian mammoth frozen for over a million years.
Applications
Evolution
Similar sequences are often found along DNA (and the derived protein polypeptide chains) in different species. This similarity is directly linked to the sequence of the DNA (the genetic material of the organism). Due to the improbability of this being random chance, and its consistency too long to be attributed to convergence by natural selection, these similarities can be plausibly linked to the existence of a common ancestor with common genes. This allows DNA sequences to be compared betwe
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https://en.wikipedia.org/wiki/Juan%20Pistarini
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Juan Pistarini (23 December 1882 – 29 May 1956) was an Argentine general and politician.
Biography
Pistarini was born in the town of Victorica, La Pampa Province. He graduated from the National Military College with a degree in civil engineering, was promoted as army major by 1921, and became a close associate of the War Minister, General Agustín Justo. Justo was elected president in 1932, and appointed Pistarini Minister of Public Works in 1935. Pistarini's his first important initiative as minister was the proposed construction of a new international airport outside Buenos Aires. He was promoted to the rank of general in 1937 and, between then and 1940, was stationed in Germany and Italy. Appointed Director of Army Engineers upon his return, Pistarini recommended German contractors for public works in Argentina and was open regarding his Nazi and Fascist sympathies.
His role in the 1943 coup d'état resulted in his appointment as director of the Campo de Mayo army training base. He was returned to the post of Minister of Public Works in March 1944 and served a brief, concurrent term as vice president following the populist Juan Perón's dismissal. Pistarini was retained as Public Works Minister by Perón when the latter was elected president in 1946, in which capacity he administered Perón's ambitious public works agenda. He oversaw and helped plan the construction or development of modern barracks, Argentina's first expressways, numerous public vacation resorts, 11,000 sc
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https://en.wikipedia.org/wiki/Turbomachinery
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Turbomachinery, in mechanical engineering, describes machines that transfer energy between a rotor and a fluid, including both turbines and compressors. While a turbine transfers energy from a fluid to a rotor, a compressor transfers energy from a rotor to a fluid.
These two types of machines are governed by the same basic relationships including Newton's second Law of Motion and Euler's pump and turbine equation for compressible fluids. Centrifugal pumps are also turbomachines that transfer energy from a rotor to a fluid, usually a liquid, while turbines and compressors usually work with a gas.
History
The first turbomachines could be identified as water wheels, which appeared between the 3rd and 1st centuries BCE in the Mediterranean region. These were used throughout the medieval period and began the first Industrial Revolution. When steam power started to be used, as the first power source driven by the combustion of a fuel rather than renewable natural power sources, this was as reciprocating engines. Primitive turbines and conceptual designs for them, such as the smoke jack, appeared intermittently but the temperatures and pressures required for a practically efficient turbine exceeded the manufacturing technology of the time. The first patent for gas turbines were filed in 1791 by John Barber. Practical hydroelectric water turbines and steam turbines did not appear until the 1880s. Gas turbines appeared in the 1930s.
The first impulse type turbine was created by Ca
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https://en.wikipedia.org/wiki/UP%20Diliman%20Department%20of%20Computer%20Science
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The Department of Computer Science is one of nine departments in the University of the Philippines Diliman College of Engineering.
Academic programs
The Department of Computer Science administers the four-year bachelor of science in computer science program and the master of science in computer science program. As of AY 2009-2010, the department had 553 undergraduate and 89 graduate students mentored by 27 faculty members, seven of whom are PhD degree holders.
Undergraduate
The bachelor of science in computer science program is designed to equip the student with knowledge of the fundamental concepts and a reasonable mastery of the basic tools and techniques in computer science. The undergraduate program incorporates the core material, which is universally accepted as common to computer science undergraduate programs (computer programming, computer organization, computer systems, data structures and algorithms, file processing, and programming languages). Underpinning the software orientation of the program are the subjects on database systems, software engineering, artificial intelligence, computer networks and special problems (primarily, software projects).
Graduate
The master of science in computer science program aims to provide the student with both breadth and depth of knowledge in the concepts and techniques related to the design, programming, and application of computing systems.
The doctor of philosophy in computer science program aims to develop computer scienti
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https://en.wikipedia.org/wiki/Ante%20Prka%C4%8Din
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Ante Prkačin (born 14 November 1953) is a Croatian politician and businessman and a former general of the Croatian Army and the Croatian Defence Council.
Biography
Prkačin was born in Slavonski Brod, where he also studied at the Faculty of Economics, in addition to the Faculty of Petrochemistry in Sisak.
In 1989, as a Croatian nationalist, he joined the christian democratic Croatian Democratic Party () and won a seat in the first assembly of the Croatian Parliament in the 1990 elections, when his party was aligned with the Coalition of People's Accord.
In the late 1991, Prkačin moved to the Croatian Party of Rights. He soon became one of its representatives in Croatian Parliament, after the second Sabor election.
In 1992, when the war escalated in Bosnia and Herzegovina, Prkačin took part as a leader of the HSP militia Croatian Defence Forces (Hrvatske obrambene snage, HOS) with the rank of general, and had close co-operation with government of Alija Izetbegović. In the fall of the same year, he was a member of the joint command of Croatian Defence Council and Army of Bosnia and Herzegovina.
After HOS was disbanded, Prkačin was commander of the defence of Posavina as HVO officer.
Upon his return to Croatia, he began to distance himself from Dobroslav Paraga and spent the rest of his time in the Sabor as independent representative.
He left HSP in 1995.
In October 1999, he founded a new party called New Croatia (Nova Hrvatska), and under its banner ran for Croatian Pres
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https://en.wikipedia.org/wiki/Index%20of%20meteorology%20articles
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This is a list of meteorology topics. The terms relate to meteorology, the interdisciplinary scientific study of the atmosphere that focuses on weather processes and forecasting. (see also: List of meteorological phenomena)
A
advection
aeroacoustics
aerobiology
aerography (meteorology)
aerology
air parcel (in meteorology)
air quality index (AQI)
airshed (in meteorology)
American Geophysical Union (AGU)
American Meteorological Society (AMS)
anabatic wind
anemometer
annular hurricane
anticyclone (in meteorology)
apparent wind
Atlantic Oceanographic and Meteorological Laboratory (AOML)
Atlantic hurricane season
atmometer
atmosphere
Atmospheric Model Intercomparison Project (AMIP)
Atmospheric Radiation Measurement (ARM)
(atmospheric boundary layer [ABL]) planetary boundary layer (PBL)
atmospheric chemistry
atmospheric circulation
atmospheric convection
atmospheric dispersion modeling
atmospheric electricity
atmospheric icing
atmospheric physics
atmospheric pressure
atmospheric sciences
atmospheric stratification
atmospheric thermodynamics
atmospheric window (see under Threats)
B
ball lightning
balloon (aircraft)
baroclinity
barotropity
barometer ("to measure atmospheric pressure")
berg wind
biometeorology
blizzard
bomb (meteorology)
buoyancy
Bureau of Meteorology (in Australia)
C
Canada Weather Extremes
Canadian Hurricane Centre (CHC)
Cape Verde-type hurricane
capping inversion (in meteorology) (see "severe thunderstorms" in
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https://en.wikipedia.org/wiki/SIGCSE
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SIGCSE is the Association for Computing Machinery's (ACM) Special Interest Group (SIG) on Computer Science Education (CSE), which provides a forum for educators to discuss issues related to the development, implementation, and/or evaluation of computing programs, curricula, and courses, as well as syllabi, laboratories, and other elements of teaching and pedagogy. SIGCSE is also the colloquial name for the SIGCSE Technical Symposium on Computer Science Education, which is the largest of the four conferences organized by SIGCSE.
The main focus of SIGCSE is higher education, and discussions include improving computer science education at high school level and below. The membership level has held steady at around 3300 members for several years. The current chair of SIGCSE is Alison Clear for July 1, 2022 to June 30, 2025.
Conferences
SIGCSE has four annual conferences.
The SIGCSE Technical Symposium on Computer Science Education is held in the United States with an average annual attendance of approximately 1600 in recent years. The most recent conference was held March 15 through March 19, 2023 in Toronto, Canada.
The annual conference on Innovation and Technology in Computer Science Education (ITiCSE). The next ITiCSE will be held July 10 - July 12, hosted by the University of Turku in Turku, Finland. This conference is attended by about 200-300 and is mainly held in Europe, but has also been held in countries outside of Europe ((Israel - 2012), and (Peru - 2016)).
The I
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https://en.wikipedia.org/wiki/Min-conflicts%20algorithm
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In computer science, the min-conflicts algorithm is a search algorithm or heuristic method to solve constraint satisfaction problems.
Given an initial assignment of values to all the variables of a constraint satisfaction problem, the algorithm randomly selects a variable from the set of variables with conflicts violating one or more its constraints. Then it assigns to this variable the value that minimizes the number of conflicts. If there is more than one value with a minimum number of conflicts, it chooses one randomly. This process of random variable selection and min-conflict value assignment is iterated until a solution is found or a pre-selected maximum number of iterations is reached.
Because a constraint satisfaction problem can be interpreted as a local search problem when all the variables have an assigned value (called a complete state), the min conflicts algorithm can be seen as a repair heuristic that chooses the state with the minimum number of conflicts.
Algorithm
algorithm MIN-CONFLICTS is
input: console.csp, A constraint satisfaction problem.
max_steps, The number of steps allowed before giving up.
current_state, An initial assignment of values for the variables in the csp.
output: A solution set of values for the variable or failure.
for i ← 1 to max_steps do
if current_state is a solution of csp then
return current_state
set var ← a randomly chosen variable from the set of conflic
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https://en.wikipedia.org/wiki/Commercial%20bandwidth
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Commercial bandwidth is a term for the regular capacity of the telephone network required for intelligible speech. It was defined as 300 to 3,400 hertz, although the modern PSTN is theoretically capable of transmitting from 0 to 7,000 Hz using ISDN.
See also
DS0
Bandwidth (signal processing)
Voice frequency
References
Telephony
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https://en.wikipedia.org/wiki/Gauge%20fixing
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In the physics of gauge theories, gauge fixing (also called choosing a gauge) denotes a mathematical procedure for coping with redundant degrees of freedom in field variables. By definition, a gauge theory represents each physically distinct configuration of the system as an equivalence class of detailed local field configurations. Any two detailed configurations in the same equivalence class are related by a gauge transformation, equivalent to a shear along unphysical axes in configuration space. Most of the quantitative physical predictions of a gauge theory can only be obtained under a coherent prescription for suppressing or ignoring these unphysical degrees of freedom.
Although the unphysical axes in the space of detailed configurations are a fundamental property of the physical model, there is no special set of directions "perpendicular" to them. Hence there is an enormous amount of freedom involved in taking a "cross section" representing each physical configuration by a particular detailed configuration (or even a weighted distribution of them). Judicious gauge fixing can simplify calculations immensely, but becomes progressively harder as the physical model becomes more realistic; its application to quantum field theory is fraught with complications related to renormalization, especially when the computation is continued to higher orders. Historically, the search for logically consistent and computationally tractable gauge fixing procedures, and efforts to dem
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https://en.wikipedia.org/wiki/Nikolai%20Rynin
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Nikolai Alekseevich Rynin (23 December 1887 – 28 July 1942) was a Russian civil engineer, teacher, aerospace researcher, author, historian, and promoter of space travel.
Career
Rynin began his career in civil engineering, working in the railway industry. However, in 1906 he developed an interest in aircraft and manned flight. During his career he performed research in aeronautics, became a balloonist and aircraft pilot, taught aerospace topics as a professor in Leningrad, and wrote various books and articles on airplanes and space travel.
In the April 1918 issue of the Byloye magazine, Rynin published Nikolai Kibalchich's description of a manned, rocket-propelled ship. It had been detailed in Kibalchich's final letter, and had languished in police archives until Rynin heard rumors of the design and fished it out.
Between 1928 and 1932 he published a nine-volume encyclopedia of space travel called the Mezhplanetnye Soobschniya ("Interplanetary Communications"). He is known to have corresponded with peers in the West, including Robert H. Goddard in 1926, concerning Russian rocketry activities.
Rynin died from a combination of starvation and illness during the German siege of Leningrad, as did fellow spaceflight promoter Yakov Perelman.
The crater Rynin on the Moon is named after him.
Interplanetary Communications
Rynin's encyclopedia contains the following nine volumes:
Dreams, Legends, and Early Fantasies
Spacecraft in Science Fiction
Radiant Energy: Science Fictio
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https://en.wikipedia.org/wiki/White%20Noise%20%28band%29
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White Noise are an English experimental electronic music band formed in London in 1968, after American-born David Vorhaus, a classical bass player with a background in physics and electronic engineering, attended a lecture by Delia Derbyshire, a sound scientist at the BBC Radiophonic Workshop. Derbyshire and Brian Hodgson, then both former members of electronic music project Unit Delta Plus, joined Vorhaus to form the band.
Biography
An Electric Storm
In June 1969 White Noise released the groundbreaking album An Electric Storm on Island Records. The album was created using a variety of tape manipulation techniques, and used the first British synthesizer, the EMS Synthi VCS3. Amongst many oddities, the first track on the album, Love Without Sound, employed sped-up tape edits of Vorhaus playing the double bass to create violin and cello sounds. Although not initially commercially successful for Island, the album is now considered an important and influential album in the development of electronic music, namechecked by contemporary artists like The Orb and Julian Cope, influencing contemporary acts such as Broadcast, Add N to (X), and Secret Chiefs 3. Peter Kember of Spacemen 3 included 'Firebird' on his 2004 curated compilation Spacelines.
White Noise 2-III-IV-V
Following the departure of Derbyshire and Hodgson, to pursue other projects, Vorhaus released a second album, the largely instrumental White Noise 2 - Concerto for Synthesizer on Virgin Records in 1974. It was record
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https://en.wikipedia.org/wiki/Haya
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Haya may refer to:
Biology
Haya (dinosaur), a genus of basal ornithopod dinosaur that lived during the Late Cretaceous from Mongolia
Haya (plant), a genus of plants in the family Caryophyllaceae
Haya de Herguijuela (Spanish: beech of Herguijela), a solitary specimen of European beech growing near the town of Herguijuela de la Sierra, Spain
Fagus mexicana, or haya, a species of beech
Myrica faya, or haya, a species of Myrica
People
Haya bint Hussein (born 1974), former wife of Sheikh Mohammed bin Rashid Al Maktoum ruler of Dubai and daughter of King Hussein of Jordan
Haya Harareet (1931–2021), Israeli actress
Haya Kaspi, Israeli mathematician
Haya bint Saad Al Sudairi (1913–2003), wife of Ibn Saud, founder of Saudi Arabia
Víctor Raúl Haya de la Torre (1895–1979), Peruvian politician
William II de Haya (12th century), a Norman knight who is considered to be the progenitor of the Scottish Clan Hay
Places
Hidaj, also written as Hayā, a city in Iran
M'Haya, Meknès Prefecture, Fès-Meknès, Morocco
Haya River (Kanagawa), a river in Kanagawa, Japan
Other uses
Haya (god), in ancient Mesopotamian religion
Haya (Islam), an Islamic term for modesty
La Haya, Spanish name for The Hague, in particular seen in references to Hague Conventions
Haya Party (; Life Party), an Egyptian political party
Haya people, a people of Tanzania
Haya language, the language of the Haya people
Haya Station, a railway station in Tanabe, Wakayama Prefecture, Japan
Hay'a tradition, in Isl
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https://en.wikipedia.org/wiki/Erik%20Ian%20Asphaug
|
Erik Ian Asphaug (born October 19, 1961 in Oslo, Norway) is a Norwegian American planetary science professor in the School of Earth and Space Exploration at University of Arizona. Asphaug received his bachelor's degree in mathematics and English from Rice University and his PhD in planetary science from the University of Arizona.
Until 2012, Asphaug served as a professor at the University of California at Santa Cruz.
The 1998 recipient of the Harold C. Urey Prize from the American Astronomical Society, Asphaug is at the forefront of scientists studying the "rubble pile" composition of most asteroids and the implications of such composition on efforts to divert asteroids from striking the Earth. Asphaug has also worked with Urey Prize winner Robin M. Canup to develop new theories on how the Moon was formed. Recently he has studied the genesis of diverse small planets and asteroids in the aftermath of collisions between similar-sized planetoids during the middle to late stages of terrestrial planet formation.
Asphaug was involved in NASA's Galileo and LCROSS missions. He is currently a principal advocate of a mission strategy to obtain a medical-like scan of the detailed interior structure of a Jupiter-family comet, which would reveal its origin, evolution and structure using techniques of 3D radar imaging and tomography.
Asteroid 7939 Asphaug was named in his honor.
Asphaug is an Eagle Scout.
Publications
When the Earth Had Two Moons: Cannibal Planets, Icy Giants, Dirt
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https://en.wikipedia.org/wiki/Robert%20Kane%20%28chemist%29
|
Sir Robert John Kane (24 September 1809 – 16 February 1890) was an Irish chemist and educator.
Early life
Kane was born at 48 Henry Street, Dublin on 24 September 1809 to John and Eleanor Kean (née Troy). His father was involved in the Irish Rebellion of 1798 and fled for a time to France where he studied chemistry. Back in Dublin, Kean (now Kane) founded the Kane Company and manufactured sulphuric acid.
The young Kane studied chemistry at his father's factory, and attended lectures at the Royal Dublin Society as a teenager. He published his first paper in 1828, Observations on the existence of chlorine in the native peroxide of manganese, in the London Quarterly Journal of Science, Literature and Art. The following year, his description of the natural arsenide of manganese resulted in the compound being named Kaneite in his honour. He studied medicine at Trinity College, Dublin, graduating in 1834 whilst working in the Meath Hospital. He was appointed Professor of Chemistry at the Apothecaries' Hall, Dublin in 1831, which earned him the moniker of the "boy professor". In the following year he participated in the founding of the Dublin Journal of Medical Science.
Academic life
Chemistry
On the strength of his book Elements of Practical Pharmacy he was elected to the Royal Irish Academy in 1832. He studied acids, showed that hydrogen was electropositive, and proposed the existence of the ethyl radical. In 1836 he travelled to Gießen in Germany to study organic chemistry
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https://en.wikipedia.org/wiki/Plant%20Proteome%20Database
|
The Plant Proteome Database is a National Science Foundation-funded project to determine the biological function of each protein in plants. It includes data for two plants that are widely studied in molecular biology, Arabidopsis thaliana and maize (Zea mays). Initially the project was limited to plant plastids, under the name of the Plastid PDB, but was expanded and renamed Plant PDB in November 2007.
See also
Proteome
References
External links
Plant Proteome Database home page
Plant physiology
Government databases in the United States
Biological databases
|
https://en.wikipedia.org/wiki/Nuclear%20matrix
|
In biology, the nuclear matrix is the network of fibres found throughout the inside of a cell nucleus after a specific method of chemical extraction. According to some it is somewhat analogous to the cell cytoskeleton. In contrast to the cytoskeleton, however, the nuclear matrix has been proposed to be a dynamic structure. Along with the nuclear lamina, it supposedly aids in organizing the genetic information within the cell.
The exact function of this structure is still disputed, and its very existence has been called into question. Evidence for such a structure was recognised as long ago as 1948, and consequently many proteins associated with the matrix have been discovered. The presence of intra-cellular proteins is common ground, and it is agreed that proteins such as the Scaffold, or Matrix Associated Proteins (SAR or MAR) have some role in the organisation of chromatin in the living cell. There is evidence that the nuclear matrix is involved in regulation of gene expression in Arabidopsis thaliana.
Whenever a similar structure can actually be found in living cells remains a topic of discussion. According to some sources, most, if not all proteins found in nuclear matrix are the aggregates of proteins of structures that can be found in the nucleus of living cells. Such structures are nuclear lamina, which consist of proteins termed lamins which can be also found in the nuclear matrix.
Validity of nuclear matrix
For a long time the question whether a polymer meshwork,
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https://en.wikipedia.org/wiki/FINO
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In computer science, FINO is a humorous scheduling algorithm. It is an acronym for first in, never out as opposed to traditional first in, first out (FIFO) and last in, first out (LIFO) algorithms. A similar acronym is "FISH", for first in, still here.
FINO works by withholding all scheduled tasks permanently. No matter how many tasks are scheduled at any time, no task ever actually takes place.
A stateful FINO queue can be used to implement a memory leak.
The first mention of FINO appears in the Signetics 25120 write-only memory joke datasheet.
See also
Bit bucket
Black hole (networking)
Null route
Write-only memory
References
Scheduling algorithms
Computer humor
|
https://en.wikipedia.org/wiki/UMAC
|
In cryptography, a message authentication code based on universal hashing, or UMAC, is a type of message authentication code (MAC) calculated choosing a hash function from a class of hash functions according to some secret (random) process and applying it to the message. The resulting digest or fingerprint is then encrypted to hide the identity of the hash function used. As with any MAC, it may be used to simultaneously verify both the data integrity and the authenticity of a message.
A specific type of UMAC, also commonly referred to just UMAC, is specified in RFC 4418, it has provable cryptographic strength and is usually a lot less computationally intensive than other MACs. UMAC's design is optimized for 32-bit architectures with SIMD support, with a performance of 1 CPU cycle per byte (cpb) with SIMD and 2 cpb without SIMD. A closely related variant of UMAC that is optimized for 64-bit architectures is given by VMAC, which has been submitted to the IETF as a draft () but never gathered enough attention for becoming a standardized RFC.
Background
Universal hashing
Let's say the hash function is chosen from a class of hash functions H, which maps messages into D, the set of possible message digests. This class is called universal if, for any distinct pair of messages, there are at most |H|/|D| functions that map them to the same member of D.
This means that if an attacker wants to replace one message with another and, from his point of view, the hash function was chos
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https://en.wikipedia.org/wiki/Jean-Guy%20Paquet
|
Jean-Guy Paquet, (born January 5, 1938) is a Canadian scientist, businessman, and former rector of Université Laval.
Born in Montmagny, Quebec, he received a Doctor of Electrical Engineering from Université Laval in 1963. From 1967 to 1969, he was the head of the electrical engineering department at Université Laval. From 1969 to 1972, he was a vice-rector of Université Laval and he was rector from 1977 to 1987. He was the youngest-ever president of a Canadian university and the second engineer to become rector at Laval.
After leaving Université Laval, he became Executive Vice President of The Laurentian Mutual Insurance Company from 1987 to 1988 and was President from 1988 to 1994. Since 1994, he has been President and CEO of the National Optics Institute.
Honours
In 1978, he was made a Fellow of the Royal Society of Canada.
In 1982, he was awarded an honorary Doctor of Sciences from McGill University.
In 1983, he was awarded an honorary Doctor of Law from York University.
In 1984, he was made an Officer of the Order of Canada.
In 1992, he was made an Officer of the National Order of Quebec.
In 1994, he was promoted to Companion of the Order of Canada.
In 2000, he was awarded the Quebec government's Prix Armand-Frappier.
In 2005, he was promoted to Grand Officer of the National Order of Quebec.
he was elected as Fellow of the Canadian Academy of Engineering.
References
1938 births
Academics in Quebec
Canadian academics in engineering
Canadian businesspeople
Canadian un
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https://en.wikipedia.org/wiki/Monadology
|
The Monadology (, 1714) is one of Gottfried Leibniz's best known works of his later philosophy. It is a short text which presents, in some 90 paragraphs, a metaphysics of simple substances, or monads.
Text
During his last stay in Vienna from 1712 to September 1714, Leibniz wrote two short texts in French which were meant as concise expositions of his philosophy. After his death, Principes de la nature et de la grâce fondés en raison, which was intended for prince Eugene of Savoy, appeared in French in the Netherlands. Christian Wolff and collaborators published translations in German and Latin of the second text which came to be known as The Monadology. Without having seen the Dutch publication of the Principes they had assumed that it was the French original of the Monadology, which in fact remained unpublished until 1840.
The German translation appeared in 1720 as Lehrsätze über die Monadologie and the following year the Acta Eruditorum printed the Latin version as Principia philosophiae. There are three original manuscripts of the text: the first written by Leibniz and glossed with corrections and two further emended copies with some corrections appearing in one but not the other. Leibniz himself inserted references to the paragraphs of his Théodicée ("Theodicy", i.e. a justification of God), sending the interested reader there for more details.
Metaphysics
Context
The monad, the word and the idea, belongs to the Western philosophical tradition and has been used by
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https://en.wikipedia.org/wiki/David%20Lee%20%28physicist%29
|
David Morris Lee (born January 20, 1931) is an American physicist who shared the 1996 Nobel Prize in Physics with Robert C. Richardson and Douglas Osheroff "for their discovery of superfluidity in helium-3." Lee is professor emeritus of physics at Cornell University and distinguished professor of physics at Texas A&M University.
Personal life
Lee was born and raised in Rye, New York. His parents, Annette (Franks), a teacher, and Marvin Lee, an electrical engineer, were children of Jewish immigrants from England and Lithuania. He graduated from Harvard University in 1952 and then joined the U.S. Army for 22 months. After being discharged from the army, he obtained a master's degree from the University of Connecticut. In 1955 Lee entered the Ph.D. program at Yale University where he worked under Henry A. Fairbank in the low-temperature physics group, doing experimental research on liquid 3He.
After graduating from Yale in 1959, Lee took a job at Cornell University, where he was responsible for setting up the new Laboratory of Atomic and Solid State Physics. Shortly after arriving at Cornell he met his future wife, Dana, then a PhD student in another department; the couple went on to have two sons.
Lee moved his laboratory from Cornell to Texas A&M University on November 16, 2009.
Work
The work that led to Lee's Nobel Prize was performed in the early 1970s. Lee, together with Robert C. Richardson and graduate student, Doug Osheroff used a Pomeranchuk cell to investigate t
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https://en.wikipedia.org/wiki/London%20Positivist%20Society
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The London Positivist Society was an atheistic philosophical, humanist, and political circle that met in London, England, between May 1867 and 1974. The conditions of membership originally included "emancipation from theology and metaphysics and the acceptance of Comte's views on science and society". The Society's members occupied themselves in applying the ideas of the philosophical school of Comtean positivism to current affairs of the day, including the movement for home rule in Ireland, the Second Boer War (which the Society opposed), the strikes of London trade unionists (which the society defended), Egyptian Independence (which the society supported), the Indian independence movement (which the Society supported) and defence of the Paris Commune. Among their writings was the 1896 pamphlet Positivist Comments on Public Affairs. The Society also supported the founding of the Sociological Society of London. In 1934, it was renamed the English Positivist Committee.
History
The society was founded by Richard Congreve (1818–1899) in 1867 as a philosophical and political body. By 1870, the group under Congreve was based at Chapel Street Hall in London. The barrister Frederic Harrison, who had met Congreve at Wadham College, Oxford, was a founding member, but he found it difficult to adhere to Congreve's rigid Comtism. In 1878 the group suffered a schism. That summer, Congreve dissolved the Society, for he wished to make sure everyone involved in the group advocated Auguste C
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https://en.wikipedia.org/wiki/Alfred%20G.%20Knudson
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Alfred George Knudson, Jr. (August 9, 1922 – July 10, 2016) was an American physician and geneticist specializing in cancer genetics. Among his many contributions to the field was the formulation of the Knudson hypothesis in 1971, which explains the effects of mutation on carcinogenesis (the development of cancer).
Early life and education
Knudson was born in Los Angeles, California in 1922. He received his B.S. from California Institute of Technology in 1944, his M.D. from Columbia University in 1947 and his Ph.D. from California Institute of Technology in 1956. He held a Guggenheim fellowship from 1953 to 1954.
Career and research
After an initial faculty appointment at the City of Hope Medical Center in California, Knudson became the Associate Dean for Basic Sciences at the State University of New York at the Stony Brook School of Medicine. From 1970 to 1976, Knudson served as the Dean of Graduate School of Biomedical Sciences, University of Texas Health Science Center at Houston in the Texas Medical Center. He was affiliated with Fox Chase Cancer Center in Philadelphia from 1976 until his death in 2016.
Knudson is best known for his "two-hit hypothesis," explaining the incidence of hereditary cancers, such as retinoblastoma. Humans inherit two copies of every gene, one from each parent (except for genes on the X and Y chromosomes in males). Some people inherit one mutated version and one normal version of the retinoblastoma gene, which produces the retinoblastoma prote
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https://en.wikipedia.org/wiki/John%20Finnis
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John Mitchell Finnis (born 28 July 1940) is an Australian legal philosopher and jurist specializing in jurisprudence and the philosophy of law. He is an original interpreter of Aristotle and Aquinas, and counts Germain Grisez as a major influence and collaborator. He has made contributions to epistemology, metaphysics, and moral philosophy.
Finnis was Professor of Law and Legal Philosophy at the University of Oxford from 1989 to 2010, where he is now Professor of Law and Legal Philosophy Emeritus. He is also the Biolchini Family Professor of Law, emeritus, at Notre Dame Law School and a Permanent Senior Distinguished Research Fellow at Notre Dame's de Nicola Center for Ethics and Culture. He acted as adviser to several Australian State governments, especially Queensland and Western Australia, mostly on the States' relations with the federal Government and with the United Kingdom.
His practice at the English Bar saw him in cases in the High Court and in the Court of Appeal. He is a member of Gray's Inn. He was appointed an honorary Queen's Counsel in 2017. In the 2019 Queen's Birthday Honours for Australia, Finnis was appointed a Companion in the General Division of the Order of Australia, the country's highest civilian honour, for his eminent service as a jurist and legal scholar. He was appointed Commander of the Order of the British Empire (CBE) in the 2023 New Year Honours for services to legal scholarship.
He has supervised several doctoral students including Neil
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https://en.wikipedia.org/wiki/Quark%20model
|
In particle physics, the quark model is a classification scheme for hadrons in terms of their valence quarks—the quarks and antiquarks that give rise to the quantum numbers of the hadrons. The quark model underlies "flavor SU(3)", or the Eightfold Way, the successful classification scheme organizing the large number of lighter hadrons that were being discovered starting in the 1950s and continuing through the 1960s. It received experimental verification beginning in the late 1960s and is a valid effective classification of them to date. The model was independently proposed by physicists Murray Gell-Mann, who dubbed them "quarks" in a concise paper, and George Zweig, who suggested "aces" in a longer manuscript. André Petermann also touched upon the central ideas from 1963 to 1965, without as much quantitative substantiation. Today, the model has essentially been absorbed as a component of the established quantum field theory of strong and electroweak particle interactions, dubbed the Standard Model.
Hadrons are not really "elementary", and can be regarded as bound states of their "valence quarks" and antiquarks, which give rise to the quantum numbers of the hadrons. These quantum numbers are labels identifying the hadrons, and are of two kinds. One set comes from the Poincaré symmetry—JPC, where J, P and C stand for the total angular momentum, P-symmetry, and C-symmetry, respectively.
The other set is the flavor quantum numbers such as the isospin, strangeness, charm, and
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https://en.wikipedia.org/wiki/Ansys
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Ansys, Inc. is an American multinational company with its headquarters based in Canonsburg, Pennsylvania. It develops and markets CAE/multiphysics engineering simulation software for product design, testing and operation and offers its products and services to customers worldwide.
Origins
Ansys was founded in 1970 by John Swanson, who sold his interest in the company to venture capitalists in 1993. Ansys went public on NASDAQ in 1996. In the 2000s, the company acquired other engineering design companies, obtaining additional technology for fluid dynamics, electronics design, and physics analysis. Ansys became a component of the NASDAQ-100 index on December 23, 2019.
The idea for Ansys was first conceived by John Swanson while working at the Westinghouse Astronuclear Laboratory in the 1960s. At the time, engineers performed finite element analysis (FEA) by hand. Westinghouse rejected Swanson's idea to automate FEA by developing general purpose engineering software, so Swanson left the company in 1969 to develop the software on his own. He founded Ansys under the name Swanson Analysis Systems Inc. (SASI) the next year, working out of his farmhouse in Pittsburgh.
Swanson developed the initial Ansys software on punch-cards and used a mainframe computer that was rented by the hour. Westinghouse hired Swanson as a consultant, under the condition that any code he developed for Westinghouse could also be included in the Ansys product line. Westinghouse also became the first Ansys
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https://en.wikipedia.org/wiki/George%20Blakley
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George Robert (Bob) Blakley Jr. was an American cryptographer and a professor of mathematics at Texas A&M University, best known for inventing a secret sharing scheme in 1979 (see ).
Biography
Blakley did his undergraduate studies in physics at Georgetown University, and received his Ph.D. in mathematics from the University of Maryland in 1960. After postdoctoral studies at Cornell University and Harvard University, he held faculty positions at the University of Illinois at Urbana–Champaign and the State University of New York at Buffalo before joining Texas A&M in 1970. At Texas A&M, he was chairman of the mathematics department from 1970 to 1978.
Blakley served on the board of directors of the International Association for Cryptologic Research from 1993 to 1995. He co-founded the International Journal of Information Security, published by Springer-Verlag, in 2000, and then served on its advisory board.
His son, George Robert (Bob) Blakley III, is also a computer security researcher.
Secret-sharing scheme
In order to split a secret into several shares, Blakley's scheme specifies the secret as a point in n-dimensional space, and gives out shares that correspond to hyperplanes that intersect the secret point. Any n such hyperplanes will specify the point, while fewer than n hyperplanes will leave at least one degree of freedom, and thus leave the point unspecified.
In contrast, Shamir's secret sharing scheme represents the secret as the y-intercept of an n-degree polynom
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https://en.wikipedia.org/wiki/Tessella
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Tessella was an international analytics and data science consulting services company owned by Capgemini. It is now the Hybrid Intelligence team, within Capgemini Engineering.
History
Tessella was founded in 1980 by Kevin Gell. Tessella moved to its first permanent office in Abingdon, Oxfordshire, in 1987. Tessella established a United States operations in 2004 in Newton, Massachusetts. Tessella purchased Analyticon, a technical consultancy in the space and defence industries, in 2005. In 2009 Tessella expanded its services to include consulting. In July 2012 Tessella existing management team completed a management buy out. Mobeus Equity Partners supported the buyout and founder Kevin Gell retained a significant minority stake and continued to serve as a board member. After the MBO, Tessella expanded its consulting and technology services to explicitly include analytics as a core capability. In December 2015 Altran acquired Tessella. In April 2020 Capgemini acquired Altran and Tessella became part of Capgemini Engineering. On 1 April 2022, Tessella ceased to be its own legal entity and is now fully integrated within Capgemini Engineering as the Hybrid Intelligence team.
Awards and honours
2015 UK IT Awards Highly Commended in the Not for Profit category
2014 UK IT Awards Innovative Mobile App of the Year
2014 Bio-IT World Best Practices Award
2013 European Rail Congress Awards
2011 The National Archives and Tessella win the Queen's Award for Enterprise Innovation
2009 Bio-I
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https://en.wikipedia.org/wiki/Regularization%20%28mathematics%29
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In mathematics, statistics, finance, computer science, particularly in machine learning and inverse problems, regularization is a process that changes the result answer to be "simpler". It is often used to obtain results for ill-posed problems or to prevent overfitting.
Although regularization procedures can be divided in many ways, the following delineation is particularly helpful:
Explicit regularization is regularization whenever one explicitly adds a term to the optimization problem. These terms could be priors, penalties, or constraints. Explicit regularization is commonly employed with ill-posed optimization problems. The regularization term, or penalty, imposes a cost on the optimization function to make the optimal solution unique.
Implicit regularization is all other forms of regularization. This includes, for example, early stopping, using a robust loss function, and discarding outliers. Implicit regularization is essentially ubiquitous in modern machine learning approaches, including stochastic gradient descent for training deep neural networks, and ensemble methods (such as random forests and gradient boosted trees).
In explicit regularization, independent of the problem or model, there is always a data term, that corresponds to a likelihood of the measurement and a regularization term that corresponds to a prior. By combining both using Bayesian statistics, one can compute a posterior, that includes both information sources and therefore stabilizes the est
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https://en.wikipedia.org/wiki/Regularization%20%28physics%29
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In physics, especially quantum field theory, regularization is a method of modifying observables which have singularities in order to make them finite by the introduction of a suitable parameter called the regulator. The regulator, also known as a "cutoff", models our lack of knowledge about physics at unobserved scales (e.g. scales of small size or large energy levels). It compensates for (and requires) the possibility that "new physics" may be discovered at those scales which the present theory is unable to model, while enabling the current theory to give accurate predictions as an "effective theory" within its intended scale of use.
It is distinct from renormalization, another technique to control infinities without assuming new physics, by adjusting for self-interaction feedback.
Regularization was for many decades controversial even amongst its inventors, as it combines physical and epistemological claims into the same equations. However, it is now well understood and has proven to yield useful, accurate predictions.
Overview
Regularization procedures deal with infinite, divergent, and nonsensical expressions by introducing an auxiliary concept of a regulator (for example, the minimal distance in space which is useful, in case the divergences arise from short-distance physical effects). The correct physical result is obtained in the limit in which the regulator goes away (in our example, ), but the virtue of the regulator is that for its finite value, the resul
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https://en.wikipedia.org/wiki/Sequential%20function%20chart
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Sequential function chart (SFC) is a visual programming language used for programmable logic controllers (PLCs). It is one of the five languages defined by IEC 61131-3 standard. The SFC standard is defined as Preparation of function charts for control systems, and was based on (itself based on binary Petri nets).
It can be used to program processes that can be split into steps.
Main components of SFC are:
Steps with associated actions;
Transitions with associated logic conditions;
Directed links between steps and transitions.
Steps in an SFC diagram can be active or inactive. Actions are only executed for active steps. A step can be active for one of two motives:
It is an initial step as specified by the programmer.
It was activated during a scan cycle and not deactivated since.
Steps are activated when all steps above it are active and the connecting transition is superable (i.e. its associated condition is true). When a transition is passed, all steps above are deactivated at once and after all steps below are activated at once.
Actions associated with steps can be of several types, the most relevant ones being Continuous (N), Set (S), and Reset (R). Apart from the obvious meaning of Set and Reset, an N action ensures that its target variable is set to 1 as long as the step is active. An SFC rule states that if two steps have an N action on the same target, the variable must never be reset to 0. It is also possible to insert LD (Ladder Diagram) actions inside an
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https://en.wikipedia.org/wiki/Small-angle%20approximation
|
The small-angle approximations can be used to approximate the values of the main trigonometric functions, provided that the angle in question is small and is measured in radians:
These approximations have a wide range of uses in branches of physics and engineering, including mechanics, electromagnetism, optics, cartography, astronomy, and computer science. One reason for this is that they can greatly simplify differential equations that do not need to be answered with absolute precision.
There are a number of ways to demonstrate the validity of the small-angle approximations. The most direct method is to truncate the Maclaurin series for each of the trigonometric functions. Depending on the order of the approximation, is approximated as either or as .
Justifications
Graphic
The accuracy of the approximations can be seen below in Figure 1 and Figure 2. As the measure of the angle approaches zero, the difference between the approximation and the original function also approaches 0.
Geometric
The red section on the right, , is the difference between the lengths of the hypotenuse, , and the adjacent side, . As is shown, and are almost the same length, meaning is close to 1 and helps trim the red away.
The opposite leg, , is approximately equal to the length of the blue arc, . Gathering facts from geometry, , from trigonometry, and , and from the picture, and leads to:
Simplifying leaves,
Calculus
Using the squeeze theorem, we can prove that
which is a formal
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https://en.wikipedia.org/wiki/Hans%20Georg%20Dehmelt
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Hans Georg Dehmelt (; 9 September 1922 – 7 March 2017) was a German and American physicist, who was awarded a Nobel Prize in Physics in 1989, for co-developing the ion trap technique (Penning trap) with Wolfgang Paul, for which they shared one-half of the prize (the other half of the Prize in that year was awarded to Norman Foster Ramsey). Their technique was used for high precision measurement of the electron magnetic moment.
Biography
At the age of ten Dehmelt enrolled in the Berlinisches Gymnasium zum Grauen Kloster, a Latin school in Berlin, where he was admitted on a scholarship. After graduating in 1940, he volunteered for service in the German Army, which ordered him to attend the University of Breslau to study physics in 1943. After a year of study he returned to army service and was captured during the Battle of the Bulge.
After his release from an American prisoner of war camp in 1946, Dehmelt returned to his study of physics at the University of Göttingen, where he supported himself by repairing and bartering old, pre-war radio sets. He completed his master's thesis in 1948 and received his PhD in 1950, both from the University of Göttingen. He was then invited to Duke University as a postdoctoral associate, emigrating in 1952. Dehmelt became an assistant professor at the University of Washington in Seattle, Washington in 1955, an associate professor in 1958, and a full professor in 1961.
In 1955 he built his first electron impact tube in George Volkoff's labor
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https://en.wikipedia.org/wiki/Sex%20differences%20in%20crime
|
Sex differences in crime are differences between men and women as the perpetrators or victims of crime. Such studies may belong to fields such as criminology (the scientific study of criminal behavior), sociobiology (which attempts to demonstrate a causal relationship between biological factors, in this case biological sex and human behaviors), or feminist studies. Despite the difficulty of interpreting them, crime statistics may provide a way to investigate such a relationship from a gender differences perspective. An observable difference in crime rates between men and women might be due to social and cultural factors, crimes going unreported, or to biological factors for example, testosterone or sociobiological theories). The nature of the crime itself may also require consideration as a factor.
Statistics have been consistent in reporting that men commit more criminal acts than women. Self-reported delinquent acts are also higher for men than for women, although lower than official data. Low levels of self control are associated with criminal activity. Many professionals have offered explanations for this sex difference. Some differing explanations include men's evolutionary tendency toward risk and violent behavior, sex differences in activity, social support, or gender inequality.
General theory of crime
The "general theory of crime" is accepted among scholars as one of the most valid theories of crime. Burton et al. (1998) assessed Gottfredson and Hirschi's (1990) wo
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https://en.wikipedia.org/wiki/Ivor%20Grattan-Guinness
|
Ivor Owen Grattan-Guinness (23 June 1941 – 12 December 2014) was a historian of mathematics and logic.
Life
Grattan-Guinness was born in Bakewell, England; his father was a mathematics teacher and educational administrator. He gained his bachelor degree as a Mathematics Scholar at Wadham College, Oxford, and an MSc (Econ) in Mathematical Logic and the Philosophy of Science at the London School of Economics in 1966. He gained both the doctorate (PhD) in 1969, and higher doctorate (D.Sc.) in 1978, in the History of Science at the University of London. He was Emeritus Professor of the History of Mathematics and Logic at Middlesex University, and a Visiting Research Associate at the London School of Economics.
He was awarded the Kenneth O. May Medal for services to the History of Mathematics by the International Commission on the History of Mathematics (ICHM) on 31 July 2009, at Budapest, on the occasion of the 23rd International Congress for the History of Science. In 2010, he was elected an Honorary Member of the Bertrand Russell Society.
Grattan-Guinness spent much of his career at Middlesex University. He was a fellow at the Institute for Advanced Study in Princeton, New Jersey, United States, and a member of the International Academy of the History of Science.
From 1974 to 1981, Grattan-Guinness was editor of the history of science journal Annals of Science. In 1979 he founded the journal History and Philosophy of Logic, and edited it until 1992. He was an associate edi
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https://en.wikipedia.org/wiki/Sparsely%20totient%20number
|
In mathematics, a sparsely totient number is a certain kind of natural number. A natural number, n, is sparsely totient if for all m > n,
where is Euler's totient function. The first few sparsely totient numbers are:
2, 6, 12, 18, 30, 42, 60, 66, 90, 120, 126, 150, 210, 240, 270, 330, 420, 462, 510, 630, 660, 690, 840, 870, 1050, 1260, 1320, 1470, 1680, 1890, 2310, 2730, 2940, 3150, 3570, 3990, 4620, 4830, 5460, 5610, 5670, 6090, 6930, 7140, 7350, 8190, 9240, 9660, 9870, ... .
The concept was introduced by David Masser and Peter Man-Kit Shiu in 1986. As they showed, every primorial is sparsely totient.
Properties
If P(n) is the largest prime factor of n, then .
holds for an exponent .
It is conjectured that .
References
Integer sequences
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https://en.wikipedia.org/wiki/Dark%20sector
|
Dark sector can mean:
Dark Sector, a third-person shooter video game
the hidden sector, also known as the dark sector, a hypothetical realm of forces in physics
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