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https://en.wikipedia.org/wiki/Hiram%20Caton
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Hiram Pendleton Caton III (16 August 1936 – 13 December 2010) was a professor of politics and history at Griffith University, Brisbane, Australia, until his retirement. He was an ethicist, a Fellow of the Australian Institute of Biology (since 1994), and a founding member of the Association for Politics and the Life Sciences. He was an officer of the International Society for Human Ethology. Caton held a National Humanities Fellowship at the National Humanities Center in 1982–83. He was the inaugural Professor of Humanities at Griffith University in Brisbane, and later the Professor of Politics and History and Head of the School of Applied Ethics there.
Education
Caton studied at the University of Chicago and received a PhD degree from Yale, with an (earned) D.Litt degree from Griffith University for his work in modern history.
Research
Caton's work has been concerned with ethics in the sciences (particularly in life sciences and medicine), the history of ideas, and on biological bases for individual, social, and political behaviour. He has published some 175 articles, across six or seven fields—medical ethics and bioethics, human ethology, modern political and economic history, anthropology (with special attention to the Freeman-Mead controversy), philosophy (with emphasis on rationalism and positivism), crowd studies, identity psychology, and problems of the integration of biological/evolutionary factors into the social sciences, especially political science.
He achieved
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https://en.wikipedia.org/wiki/James%20R.%20Barr
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James Robertson Barr A.M.I.E.E. (22 October 1884 – 5 December 1910) was a Scottish engineer and lecturer in Electrical Engineering at Heriot-Watt College, Edinburgh.
He was an apprentice to Bruce Peebles & Co. Ltd. and spent a year at the Leith Power Station. He then was designer to the Electric Construction Company and took some plant to West Africa for erection.
In October 1905 he was appointed assistant lecturer in Electrical Engineering at Heriot Watt College. He was elected associated member of the Institution of Electrical Engineers in 1906.
Despite his death by tuberculosis at the age of 26, his 1908 textbook Principles of Direct-Current Electrical Engineering was revised and reprinted until the 1950s. The companion volume The Design of Alternating Current Machinery was written but not yet revised for publication at the time of his death. Robert Archibald from Dundee Technical College revised and corrected the proofs for its publication in 1913.
He was awarded three medals for student achievement:
Physics & Mathematics, 1900–1901 Session, Leith Technical College.
Advanced Electricity & Magnetism, 1901–1902 Session, Heriot-Watt College.
Mathematics Stage III, 1902–1903 Session, Heriot-Watt College.
References
1884 births
1910 deaths
Scottish non-fiction writers
Academics of Heriot-Watt University
Scottish electrical engineers
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https://en.wikipedia.org/wiki/Programming%20language%20theory
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Programming language theory (PLT) is a branch of computer science that deals with the design, implementation, analysis, characterization, and classification of formal languages known as programming languages. Programming language theory is closely related to other fields including mathematics, software engineering, and linguistics. There are a number of academic conferences and journals in the area.
History
In some ways, the history of programming language theory predates even the development of programming languages themselves. The lambda calculus, developed by Alonzo Church and Stephen Cole Kleene in the 1930s, is considered by some to be the world's first programming language, even though it was intended to model computation rather than being a means for programmers to describe algorithms to a computer system. Many modern functional programming languages have been described as providing a "thin veneer" over the lambda calculus, and many are easily described in terms of it.
The first programming language to be invented was Plankalkül, which was designed by Konrad Zuse in the 1940s, but not publicly known until 1972 (and not implemented until 1998). The first widely known and successful high-level programming language was Fortran, developed from 1954 to 1957 by a team of IBM researchers led by John Backus. The success of FORTRAN led to the formation of a committee of scientists to develop a "universal" computer language; the result of their effort was ALGOL 58. Separatel
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https://en.wikipedia.org/wiki/All%20gas-phase%20iodine%20laser
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All gas-phase iodine laser (AGIL) is a chemical laser using gaseous iodine as a lasing medium. Like the chemical oxygen iodine laser (COIL), it operates at the 1.315 µm wavelength (near-infrared).
AGIL was developed in order to eliminate the problems with aqueous chemistry of the COILs. AGIL uses a reaction of chlorine atoms with gaseous hydrazoic acid, resulting in excited molecules of chloronitrene (NCl), which then pass their energy to the iodine atoms much like the singlet oxygen does in COIL. The iodine atoms then emit the laser radiation itself.
AGIL has numerous advantages over COIL. The chemicals are all in gaseous phase, therefore easier to work with than liquids, especially in microgravity conditions. The chemicals are also lighter, which is a significant advantage in aerospace applications.
See also
List of laser articles
References
External links
A new all gas-phase chemical iodine laser
Chemical lasers
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https://en.wikipedia.org/wiki/Gerald%20Garcia
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Gerald Garcia (born 1949 in Hong Kong) is a British classical guitarist and composer.
After studying chemistry at Oxford University, he became a professional musician, making his debut at the Wigmore Hall in London. His more than fifteen CDs have sold more than 30,000 copies worldwide. In addition, he has performed with other musicians including John Williams, Paco Peña and John Renbourn.
Garcia is also known as a composer, particularly for his Etudes Esquisses for guitar, recorded for Naxos Records by John Holmquist. He is musical director of the National Youth Guitar Ensemble.
Gerald Garcia lives in Oxford, where, according to his website, he enjoys "cooking, computer music, Taoist Yoga and conducting the odd chamber orchestra."
References
1949 births
British classical guitarists
British male guitarists
British composers
Living people
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https://en.wikipedia.org/wiki/Replica%20trick
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In the statistical physics of spin glasses and other systems with quenched disorder, the replica trick is a mathematical technique based on the application of the formula:
or:
where
is most commonly the partition function, or a similar thermodynamic function.
It is typically used to simplify the calculation of , the expected value of , reducing the problem to calculating the disorder average where is assumed to be an integer. This is physically equivalent to averaging over copies or replicas of the system, hence the name.
The crux of the replica trick is that while the disorder averaging is done assuming to be an integer, to recover the disorder-averaged logarithm one must send continuously to zero. This apparent contradiction at the heart of the replica trick has never been formally resolved, however in all cases where the replica method can be compared with other exact solutions, the methods lead to the same results. (A natural sufficient rigorous proof that the replica trick works would be to check that the assumptions of Carlson's theorem hold, especially that the ratio is of exponential type less than .)
It is occasionally necessary to require the additional property of replica symmetry breaking (RSB) in order to obtain physical results, which is associated with the breakdown of ergodicity.
General formulation
It is generally used for computations involving analytic functions (can be expanded in power series).
Expand using its power series: into powers
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https://en.wikipedia.org/wiki/Edilberto%20Evangelista
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Edilberto Evangelista (February 24, 1862 – February 17, 1897) was a Filipino civil engineer and a revolutionary.
Early life and career
He was born in Sta. Cruz, Manila, on February 24, 1862. Evangelista finished his Bachelor of Arts at the Colegio de San Juan de Letran in 1878. He was awarded a medal of excellence in Mathematics. Poor health made him to drop his idea of studying medicine. After this, he became a teacher, a cattle dealer, a tobacco merchant between Cebu and Manila, and later a contractor of public works. He soon went to Madrid in 1890. It was during this time that he befriended many Filipino patriots, including José Rizal, who advised him to study engineering in Belgium. He therefore enrolled at the University of Ghent, one of the world's top engineering schools, and finished civil engineering and architecture with highest honors. He then received profitable offers of employment from several institutions in Europe but he declined because of his zeal to serve his country.
Philippine Revolution
He returned to the Philippines in September 1896, shortly after the start of the Philippine Revolution. He was arrested and imprisoned, since the Spanish authorities suspected many people of the revolution and he had in his possession Jose Rizal's Noli Me Tangere and El Filibusterismo, but he escaped. He joined General Emilio Aguinaldo's command on October 22, 1896. At the Imus Assembly on December 31, 1896, Evangelista had submitted his draft of a constitution as reque
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https://en.wikipedia.org/wiki/Johannes%20Lepsius
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Johannes Lepsius (15 December 1858, Potsdam, Germany – 3 February 1926, Meran, Italy) was a German Protestant missionary, Orientalist, and humanist with a special interest in trying to prevent the Armenian genocide in the Ottoman Empire. He initially studied mathematics and philosophy in Munich and a PhD in 1880 with an already award-winning work. Lepsius was one of the founders and the first chairman of the German–Armenian Society.
During World War I he published his work "Bericht über die Lage des armenischen Volkes in der Türkei" ("Report on the situation of the Armenian People in Turkey") in which he meticulously documented and condemned the Armenian genocide. A second edition entitled "Der Todesgang des armenischen Volkes" ("The way to death of the Armenian people") included an interview with Enver Pasha, one of the chief architects of the genocide. Lepsius had to publish the report secretly because Turkey was an ally of the German Empire and the official military censorship soon forbade the publication because it feared that it would affront the strategically important Turkish ally. However Lepsius managed to distribute more than 20,000 copies of the report.
In his novel The Forty Days of Musa Dagh ("Die vierzig Tage des Musa Dagh") the Austrian-Jewish author Franz Werfel portrayed Lepsius as a "guardian angel of the Armenians". Today, the intellectual heritage of Johannes Lepsius was collected by the German church historian Hermann Goltz, who installed the "Johannes
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https://en.wikipedia.org/wiki/John%20Bindernagel
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John Albert Bindernagel (December 22, 1941 – January 17, 2018) was a wildlife biologist who sought evidence for Sasquatch since 1963.
Biography
Bindernagel was born in Kitchener, Ontario, attended the University of Guelph, and received a PhD in Biology from the University of Wisconsin–Madison. He moved to British Columbia in 1975 largely because the region was a hot spot for Bigfoot sightings. Over the years, he collected casts of tracks that he believed belonged to Bigfoot. He also claimed to have heard the creature near Comox Lake in 1992, comparing its whooping sound to that of a chimpanzee. Bindernagel believed that the Bigfoot phenomena should receive more attention from serious scientists, but remarked, "The evidence doesn't get scrutinized objectively. We can't bring the evidence to our colleagues because it's perceived as taboo."
He published a book in 1998 entitled North America's Great Ape: The Sasquatch. His second book, The Discovery of the Sasquatch: Reconciling Culture, History and Science in the Discovery Process, was published in 2010.
Bindernagel was a curator with the Bigfoot Field Researchers Organization (BFRO) until his death. Bindernagel died on January 17, 2018, at the age of 76. His cause of death was determined as cancer.
Reception
Bindernagel's claim that the sasquatch is a real wildlife species was not accepted by the scientific community. His book, North America's Great Ape: The Sasquatch was reviewed by James Lazell and Jeannine Caldbeck in t
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https://en.wikipedia.org/wiki/Civitella%20Alfedena
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Civitella Alfedena is a small town and comune in the province of L'Aquila (Abruzzo, central Italy). It is located in the heart of the National Park of Abruzzo, Lazio e Molise.
Main sights
"Lupo Appenninico Museum", dedicated to the history and the biology of the Apennine Mountains' wolf.
Twin towns
Canal San Bovo, Italy
References
External links
Page dedicated to Civitella Alfedena
Cities and towns in Abruzzo
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https://en.wikipedia.org/wiki/Dumbbell%20%28disambiguation%29
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A dumbbell is a piece of equipment used in weight training.
Dumbbell may also refer to:
Dumbbells (film), a 2014 film
The Dumbbell Nebula is a planetary nebula (M27), which is shaped like a dumbbell
Physics: A p atomic orbital has the approximate shape of a pair of lobes on opposite sides of the nucleus, or a somewhat dumbbell shape
The name "dumbbell tenement" was also used for the apartment buildings in the Lower East Side of New York City in the late 19th century
A "dumbbell interchange" is a type of road interchange
Dumbbell interstitials, a type of crystal defect
DUMBBELLS, mnemonic for cholinergic overdose, also known as SLUDGE syndrome
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https://en.wikipedia.org/wiki/Metaphrog
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Metaphrog are graphic novelists Sandra Marrs and John Chalmers, best known for making the Louis series of comics.
History
Marrs is originally from France, where she studied Arts and Letters. Chalmers is from the west of Scotland and has a scientific background with a PhD in Electronic and Electrical Engineering in Micromachining. Together they live in Glasgow.
In general, Marrs draws the comics while Chalmers writes the scripts. They started their first comic together, Strange Weather Lately, in 1995. The Sunday Herald in Glasgow described Strange Weather Lately as "the existential adventures of Martin Nitram, an unpaid theatre worker engaged in an attempt to mount a cursed play, The Crimes Of Tarquin J Swaffe." (Beadie, Brian (23 May 1999). "Comically graphic tales from the Glasgow underground". The Sunday Herald, p. 7.)
The Strange Weather Lately comics ran for 10 issues until 1999, and were then collected into two graphic novels.
They then moved on to the Louis (graphic novel) series, which includes Louis - Red Letter Day, Louis - Lying To Clive, Louis - The Clown's Last Words, Louis - Dreams Never Die and Louis - Night Salad. In 2011, they redrew and repainted Louis - Red Letter Day and this new version was published in hardback.
Louis - Red Letter Day and Louis - Lying to Clive were also each published as a webcomic on serializer.
Metaphrog were part of a collection of 80 artists from three continents to express their "visions and thoughts on the oft forgotten aspe
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https://en.wikipedia.org/wiki/Brendan%20McKay%20%28mathematician%29
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Brendan Damien McKay (born 26 October 1951 in Melbourne, Australia) is an Australian computer scientist and mathematician. He is currently an Emeritus Professor in the Research School of Computer Science at the Australian National University (ANU). He has published extensively in combinatorics.
McKay received a Ph.D. in mathematics from the University of Melbourne in 1980, and was appointed Assistant Professor of Computer Science at Vanderbilt University, Nashville in the same year (1980–1983). His thesis, Topics in Computational Graph Theory, was written under the direction of Derek Holton. He was awarded the Australian Mathematical Society Medal in 1990. He was elected a Fellow of the Australian Academy of Science in 1997, and appointed Professor of Computer Science at the ANU in 2000.
Mathematics
McKay is the author of at least 127 refereed articles.
One of McKay's main contributions has been a practical algorithm for the graph isomorphism problem and its software implementation NAUTY (No AUTomorphisms, Yes?). Further achievements include proving with Stanisław Radziszowski that the Ramsey number R(4,5) = 25; proving with Radziszowski that no 4-(12, 6, 6) combinatorial designs exist, determining with Gunnar Brinkmann, the number of posets on 16 points, and determining with Ian Wanless the number of Latin squares of size 11. Together with Brinkmann, he also developed the Plantri programme for generating planar triangulations and planar cubic graphs.
The McKay–Miller–Šir
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https://en.wikipedia.org/wiki/James%20McGaugh
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James L. McGaugh (born December 17, 1931) is an American neurobiologist and author working in the field of learning and memory. He is a Distinguished Professor Emeritus in the Department of Neurobiology and Behavior at the University of California, Irvine and a fellow and founding director of the Center for the Neurobiology of Learning and Memory.
Education and positions
McGaugh received his B.A. from San Jose State University in 1953 and his Ph.D. in psychology from the University of California, Berkeley, in 1959. He was briefly a professor at San Jose State and then did postdoctoral work in neuropharmacology with Nobel Laureate Professor Daniel Bovet at the Istituto Superiore di Sanitá in Rome, Italy. He then became a professor at the University of Oregon from 1961 to 1964. He was recruited to the University of California, Irvine, in 1964 (the year of the school's founding) to be the founding chair of the Department of Psychobiology (now Neurobiology and Behavior). He became second dean (1967–1970) of the School of Biological Sciences following Edward Steinhaus, then Vice Chancellor (1975–1977) and executive Vice Chancellor (1978–1982) of the university. In 1982, he founded the Center for the Neurobiology of Learning and Memory and remained director from 1982 to 2004.
Early research findings
McGaugh's early work (in the 1950s and 1960s) demonstrated that memories are not instantly created in a long-term, permanent fashion. Rather, immediately after a learning even
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https://en.wikipedia.org/wiki/Albert%20A.%20Murphree
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Albert Alexander Murphree (April 29, 1870 – December 20, 1927) was an American college professor and university president. Murphree was a native of Alabama, and became a mathematics instructor after earning his bachelor's degree. He later served as the third president of Florida State College (later renamed Florida State University) from 1897 to 1909, and the second president of the University of Florida from 1909 to 1927. Murphree is the only person to have been the president of both of Florida's original state universities, the University of Florida and Florida State University, and he played an important role in the organization, growth and ultimate success of both institutions.
Early life and education
Murphree was born near Chepultepec, Alabama in 1870. His father was Jesee Ellis Murphree, a Confederate veteran of the Civil War; his mother was Emily Helen Cornelius. His parents raised him in a family of ten children in Walnut Grove, Alabama, where he attended community schools and a local two-year college. He graduated from the University of Nashville with a Bachelor of Arts degree in 1894, and taught mathematics at several high schools and small colleges in Alabama, Tennessee and Texas. In 1895, he became a mathematics instructor at the West Florida Seminary (now known as Florida State University) in Tallahassee, Florida, and two years later, its board of trustees appointed him as the seminary's third president in 1897, at the age of 27. Later, Murphree marri
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https://en.wikipedia.org/wiki/Alexander%20Mirzayan
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Alexander Zavenovich Mirzayan () (born on July 20, 1945) is a Russian poet, composer, songwriter, bard and bard music theoretician. He was born in Baku. In 1969 he graduated from Bauman Moscow State Technical University and worked as a physics engineer in the Moscow Institute for Theoretical and Experimental Physics.
The first songs were written in 1969. From 1970 he started to participate in the Moscow KSP (Klub Samodejatel'noj Pesni, Clubs of Amateur Song) activities. Mirzayan became laureate of numerous KSP festivals at that time. In 1970-1980, Mirzayan's active civil stand and his affinity to the underground culture (poetry of Daniil Kharms, Joseph Brodsky etc.) caused conflicts with official rule.
Mirzayan writes songs both for his own poetry as well as poetry of other Russian poets Sosnora, Brodsky, Harms, Tsvetaeva, Chuhonzev and others. From the end of 1990, Mirzayan started research on the historical and philosophical aspects of the song phenomena.
External links
Alexander Mirzayan - video
Interview with Mirzayan by Natella Boltyanskaya at Echo of Moscow
at Hyperion, 19.02.14
References
1945 births
Living people
Musicians from Baku
Soviet Armenians
Russian people of Armenian descent
Russian bards
Russian male poets
Soviet songwriters
Soviet poets
Soviet male writers
20th-century Russian male writers
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https://en.wikipedia.org/wiki/Ronald%20Coll%C3%A9
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Ronald Collé (born February 11, 1946) is a specialist in nuclear and radiochemistry, radionuclidic metrology, and the development of standards. He has worked at the National Institute of Standards and Technology (NIST) from 1976 to 2003 and from 2005 to present, and currently serves as a research chemist in the Radioactivity Group of the NIST Physics Laboratory (Ionizing Radiation Division).
Previously, he held research positions at Brookhaven National Laboratory, and at the University of Maryland, College Park. He received a B.Sc. in chemistry from the Georgia Institute of Technology in 1969, a Ph.D. in chemistry (nuclear and radiochemistry) from Rensselaer Polytechnic Institute in 1972,
and an M.S. Adm. (Administration of Science and Technology) from George Washington University in 1979.
Collé and his collaborators have maintained, expanded and improved radioactivity measurement standards for radium-226 and radon-222 to address the requirements to measure these nuclides in drinking water. Collé and collaborators developed methods to analyse and standardize brachytherapy sources, pellets of radioactive material designed to be implanted in the body at site requiring direct radiation exposure.
An important part of metrology and standards development is understanding and taking into account uncertainties that are inherent in the instruments or that arise from methodology. Collé co-authored a paper with Churchill Eisenhart and Harry Ku, which was the forerunner of the 1993
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https://en.wikipedia.org/wiki/Probabilistic%20metric%20space
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In mathematics, probabilistic metric spaces are a generalization of metric spaces where the distance no longer takes values in the non-negative real numbers , but in distribution functions.
Let D+ be the set of all probability distribution functions F such that F(0) = 0 (F is a nondecreasing, left continuous mapping from R into [0, 1] such that max(F) = 1).
Then given a non-empty set S and a function F: S × S → D+ where we denote F(p, q) by Fp,q for every (p, q) ∈ S × S, the ordered pair (S, F) is said to be a probabilistic metric space if:
For all u and v in S, if and only if for all x > 0.
For all u and v in S, .
For all u, v and w in S, and for .
Probability metric of random variables
A probability metric D between two random variables X and Y may be defined, for example, as
where F(x, y) denotes the joint probability density function of the random variables X and Y. If X and Y are independent from each other then the equation above transforms into
where f(x) and g(y) are probability density functions of X and Y respectively.
One may easily show that such probability metrics do not satisfy the first metric axiom or satisfies it if, and only if, both of arguments X and Y are certain events described by Dirac delta density probability distribution functions. In this case:
the probability metric simply transforms into the metric between expected values , of the variables X and Y.
For all other random variables X, Y the probability metric does not satisfy th
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https://en.wikipedia.org/wiki/Top%20type
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In mathematical logic and computer science, some type theories and type systems include a top type that is commonly denoted with top or the symbol ⊤. The top type is sometimes called also universal type, or universal supertype as all other types in the type system of interest are subtypes of it, and in most cases, it contains every possible object of the type system. It is in contrast with the bottom type, or the universal subtype, which every other type is supertype of and it is often that the type contains no members at all.
Support in programming languages
Several typed programming languages provide explicit support for the top type.
In statically-typed languages, there are two different, often confused, concepts when discussing the top type.
A universal base class or other item at the top of a run time class hierarchy (often relevant in object-oriented programming) or type hierarchy; it is often possible to create objects with this (run time) type, or it could be found when one examines the type hierarchy programmatically, in languages that support it
A (compile time) static type in the code whose variables can be assigned any value (or a subset thereof, like any object pointer value), similar to dynamic typing
The first concept often implies the second, i.e., if a universal base class exists, then a variable that can point to an object of this class can also point to an object of any class. However, several languages have types in the second regard above (e.g., void
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https://en.wikipedia.org/wiki/Difference%20hierarchy
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In set theory, a branch of mathematics, the difference hierarchy over a pointclass is a hierarchy of larger pointclasses
generated by taking differences of sets. If Γ is a pointclass, then the set of differences in Γ is . In usual notation, this set is denoted by 2-Γ. The next level of the hierarchy is denoted by 3-Γ and consists of differences of three sets:
. This definition can be extended recursively into the transfinite to α-Γ for some ordinal α.
In the Borel hierarchy, Felix Hausdorff and Kazimierz Kuratowski proved that the countable levels of the
difference hierarchy over Π0γ give
Δ0γ+1.
References
Descriptive set theory
Mathematical logic hierarchies
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https://en.wikipedia.org/wiki/Bjarni%20J%C3%B3nsson
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Bjarni Jónsson (February 15, 1920 – September 30, 2016) was an Icelandic mathematician and logician working in universal algebra, lattice theory, model theory and set theory. He was emeritus distinguished professor of mathematics at Vanderbilt University and the honorary editor in chief of Algebra Universalis. He received his PhD in 1946 at UC Berkeley under supervision of Alfred Tarski.
In 2012, he became a fellow of the American Mathematical Society.
Work
Jónsson's lemma as well as several mathematical objects are named after him, among them Jónsson algebras, ω-Jónsson functions, Jónsson cardinals, Jónsson terms, Jónsson–Tarski algebras and Jónsson–Tarski duality.
Publications
References
Further reading
Kirby A. Baker, Bjarni Jónsson's contributions in algebra, Algebra Universalis, September 1994, Volume 31, Issue 3, pp. 306–336.
J. B. Nation, Jónsson's contributions to lattice theory, Algebra Universalis, September 1994, Volume 31, Issue 3, pp. 430–445.
External links
Bjarni Jónsson's homepage
1920 births
Bjarni Jonsson
Algebraists
Lattice theorists
20th-century mathematicians
University of California, Berkeley alumni
Vanderbilt University faculty
Fellows of the American Mathematical Society
Bjarni Jonsson
2016 deaths
Brown University faculty
Icelandic expatriates in the United States
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https://en.wikipedia.org/wiki/Steven%20Collins
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Steven Collins is a computer scientist who has founded and acted as CTO of several companies in the area of computer graphics and video games. Formerly a professor of computer graphics in the Department of Computer Science in Trinity College, Dublin, was co-manager of the GV2 Research Group. Born in Dundalk, County Louth, his interests in computing began with the Commodore 64 where he single-handedly developed and released the games Badlands and Herobotix.
He is also a co-founder of Havok, a company which provides physics simulation software for computer games and films. The company was sold to Intel in September 2007 for €76M.
In 2005, he was recognized by PC Gamer magazine as being one of the top 50 game industry influencers of that year.
In 2007, Collins started the MSc in Interactive Entertainment Technology course in Trinity College Dublin, where he acts as course director and lectures in real-time rendering. He is quoted as saying that the course was started in order to educate the "future captains of industry" in reference to the games industry. Both Collins and Hugh Reynolds were awarded the Trinity College Dublin Innovation Award for 2007, for their work in co-founding Havok. In March 2008, Collins and Reynolds co-founded "Kore Virtual Machines", a company dedicated to designing computer gaming virtual machines, using the Lua programming language. In October 2007, Kore was purchased by Havok and integrated into their software suite as Havok Script. Collins is curr
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https://en.wikipedia.org/wiki/Carbon%20%28disambiguation%29
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Carbon is a chemical element with symbol C and atomic number 6.
Carbon may also refer to:
In science
Chemistry
Carbon black, a filler often used to improve the properties of rubber or plastic compounds
Carbon chauvinism, a term meant to disparage the assumption that the molecules responsible for the mechanisms of life must be based on carbon
Carbon (fiber), can refer to carbon filament thread, or to felt or woven cloth made from those carbon filaments
Carbon offset, a reduction in emissions of carbon dioxide
Isotopes of carbon
Carbon dioxide equivalent, a greenhouse gas measurement
"Carbon", shorthand for radiative forcings which effect the carbon cycle and increase global warming, such as greenhouse gases
Computers and electronics
Carbon (API), a deprecated application programming interface for Mac OS X
Need for Speed: Carbon, a computer racing game developed by Electronic Arts
ThinkPad X1 Carbon, a notebook computer released by Lenovo
Rio Carbon, a product line of digital audio players
WSO2 Carbon, an open-source middleware platform
Carbon (programming language), an experimental general-purpose programming language
People
Lolita Carbon (born 1952), Filipino singer, member of Asin
Places
Canada
Carbon, Alberta, a village in Kneehill County
United States
Carbon, Indiana, a town in Clay County
Carbon, Iowa, a city in Adams County
Carbon, Pennsylvania
Carbon, Texas, a town in Eastland County
Carbon County (disambiguation), multiple places
Other uses
Carbon (2017 film
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https://en.wikipedia.org/wiki/Schur-convex%20function
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In mathematics, a Schur-convex function, also known as S-convex, isotonic function and order-preserving function is a function that for all such that is majorized by , one has that . Named after Issai Schur, Schur-convex functions are used in the study of majorization. Every function that is convex and symmetric is also Schur-convex. The opposite implication is not true, but all Schur-convex functions are symmetric (under permutations of the arguments).
Schur-concave function
A function f is 'Schur-concave' if its negative, −f, is Schur-convex.
Schur-Ostrowski criterion
If f is symmetric and all first partial derivatives exist, then
f is Schur-convex if and only if
for all
holds for all .
Examples
is Schur-concave while is Schur-convex. This can be seen directly from the definition.
The Shannon entropy function is Schur-concave.
The Rényi entropy function is also Schur-concave.
is Schur-convex.
The function is Schur-concave, when we assume all . In the same way, all the elementary symmetric functions are Schur-concave, when .
A natural interpretation of majorization is that if then is more spread out than . So it is natural to ask if statistical measures of variability are Schur-convex. The variance and standard deviation are Schur-convex functions, while the median absolute deviation is not.
If is a convex function defined on a real interval, then is Schur-convex.
A probability example: If are exchangeable random variables, then the functio
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https://en.wikipedia.org/wiki/8A
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8A, VIII-A or 8a may refer to :
Aisle 8A, the 64th episode of the animated situation comedy King of the Hill
Bone morphogenetic protein 8A in biochemistry
Cyg OB2 -8A, a blue star
Greek National Road 8A
GCR Class 8A, a class of British 0-8-0 steam locomotive
Isotta Fraschini Tipo 8A, a successor to the Tipo 8 model car
Massachusetts Route 8A
Nevada State Route 8A
Secondary State Highway 8A (Washington)
Stalag VIII-A, a German prisoners of war camp
and also :
Atlas Blue IATA airline designator
8(a) Business Development Program a loan program administered by the U.S. Small Business Administration
See also
A8 (disambiguation)
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https://en.wikipedia.org/wiki/Hempel%27s%20dilemma
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Hempel's dilemma is a question first asked (at least on record) by the philosopher Carl Hempel. It has relevance to naturalism and physicalism in philosophy, and to philosophy of mind.
The dilemma questions how the language of physics can be used to accurately describe existence, given that it relies on imperfect human linguistics, or as Hempel stated: "The thesis of physicalism would seem to require a language in which a true theory of all physical phenomena can be formulated. But it is quite unclear what is to be understood here by a physical phenomenon, especially in the context of a doctrine that has taken a decidedly linguistic turn."
Overview
Physicalism, in at least one rough sense, is the claim that the entire world may be described and explained using the laws of nature, in other words, that all phenomena are natural phenomena. This leaves open the question of what is 'natural' (in physicalism 'natural' means procedural, causally coherent or all effects have particular causes regardless of human knowledge [like physics] and interpretation and it also means 'ontological reality' and not just a hypothesis or a calculational technique), but one common understanding of the claim is that everything in the world is ultimately explicable in the terms of physics. This is known as reductive physicalism. However, this type of physicalism in its turn leaves open the question of what we are to consider as the proper terms of physics. There seem to be two options here, and t
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https://en.wikipedia.org/wiki/Paclitaxel%20total%20synthesis
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Paclitaxel total synthesis in organic chemistry is a major ongoing research effort in the total synthesis of paclitaxel (Taxol). This diterpenoid is an important drug in the treatment of cancer but, also expensive because the compound is harvested from a scarce resource, namely the Pacific yew (Taxus brevifolia). Not only is the synthetic reproduction of the compound itself of great commercial and scientific importance, but it also opens the way to paclitaxel derivatives not found in nature but with greater potential.
The paclitaxel molecule consists of a tetracyclic core called baccatin III and an amide tail. The core rings are conveniently called (from left to right) ring A (a cyclohexene), ring B (a cyclooctane), ring C (a cyclohexane) and ring D (an oxetane).
The paclitaxel drug development process took over 40 years. The anti-tumor activity of a bark extract of the Pacific yew tree was discovered in 1963 as a follow-up of a US government plant screening program already in existence 20 years before that. The active substance responsible for the anti-tumor activity was discovered in 1969 and structure elucidation was completed in 1971. Robert A. Holton of Florida State University succeeded in the total synthesis of paclitaxel in 1994, a project that he had started in 1982. In 1989 Holton had also developed a semisynthetic route to paclitaxel starting from 10-deacetylbaccatin III. This compound is a biosynthetic precursor and is found in larger quantities than paclitaxel
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https://en.wikipedia.org/wiki/Curt%20Michel
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Frank Curtis "Curt" Michel (June 5, 1934 – February 26, 2015) was an American astrophysicist; a professor of astrophysics at Rice University in Houston, Texas; a United States Air Force pilot; and a NASA astronaut.
Personal life
Michel was born June 5, 1934, to parents to Frank and Viola Michel. He was married to Bonnie Hausman, a web technical specialist. He had two children, Alice and Jeff with his first wife Beverly, who preceded him in death, and three grandchildren. His hobbies were photography, tennis, handball, and baseball. Michel died at the age of 80 on February 26, 2015. He was buried with full military honors at the Houston National Cemetery.
Education
Michel graduated from C. K. McClatchy High School, located at Sacramento, California, in 1951. In 1955, he received a Bachelor of Science degree with honors in physics, and in 1962 he received a doctorate in physics, both from the California Institute of Technology. His thesis was "Beta Spectra of the Mass 12 Nuclei" and his dissertation advisor was Thomas Lauritsen. Nobel laureate William Alfred Fowler also served on his committee.
While on the faculty of Rice University, Michel oversaw the dissertations of Jerry Modisette, Robert LaQuey, Robert Manka, Cliff Morris, Michael Pelizzari, Jürgen Krause-Polstorff, James Sokolowski, and Steven Sturner.
Organizations
Michel was a fellow of the American Physical Society and a member of the American Geophysical Union, and the American Astronomical Society.
Experien
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https://en.wikipedia.org/wiki/Anomeric%20effect
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In organic chemistry, the anomeric effect or Edward-Lemieux effect (after J. T. Edward and Raymond Lemieux) is a stereoelectronic effect that describes the tendency of heteroatomic substituents adjacent to a heteroatom within a cyclohexane ring to prefer the axial orientation instead of the less-hindered equatorial orientation that would be expected from steric considerations. This effect was originally observed in pyranose rings by J. T. Edward in 1955 when studying carbohydrate chemistry.
The term anomeric effect was introduced in 1958. The name comes from the term used to designate the lowest-numbered ring carbon of a pyranose, the anomeric carbon. Isomers that differ only in the configuration at the anomeric carbon are called anomers. The anomers of D-glucopyranose are diastereomers, with the beta anomer having a hydroxyl () group pointing up equatorially, and the alpha anomer having that () group pointing down axially.
The anomeric effect can also be generalized to any cyclohexyl or linear system with the general formula , where Y is a heteroatom with one or more lone pairs, and X is an electronegative atom or group. The magnitude of the anomeric effect is estimated at about 1–2 kcal/mol in the case of sugars, but is different for every molecule.
In the above case, the methoxy group ) on the cyclohexane ring (top) prefers the equatorial position. However, in the tetrahydropyran ring (bottom), the methoxy group prefers the axial position. This is because in the cyclohe
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https://en.wikipedia.org/wiki/Universal%20one-way%20hash%20function
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In cryptography a universal one-way hash function (UOWHF, often pronounced "woof"), is a type of universal hash function of particular importance to cryptography. UOWHF's are proposed as an alternative to collision-resistant hash functions (CRHFs). CRHFs have a strong collision-resistance property: that it is hard, given randomly chosen hash function parameters, to find any collision of the hash function. In contrast, UOWHFs require that it be hard to find a collision where one preimage is chosen independently of the hash function parameters. The primitive was suggested by Moni Naor and Moti Yung and is also known as "target collision resistant" hash functions; it was employed to construct general digital signature schemes without trapdoor functions, and also within chosen-ciphertext secure public key encryption schemes.
The UOWHF family contains a finite number of hash functions with each
having the same probability of being used.
Definition
The security property of a UOWHF is as follows. Let be an algorithm that operates in two phases:
Initially, receives no input (or, just a security parameter) and chooses a value .
A hash function is chosen randomly from the family. then receives and must output such that .
Then for all polynomial-time the probability that succeeds is negligible.
Applications
UOWHFs are thought to be less computationally expensive than CRHFs, and are most often used for efficiency purposes in schemes where the choice of the hash functio
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https://en.wikipedia.org/wiki/Heat%20kernel
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In the mathematical study of heat conduction and diffusion, a heat kernel is the fundamental solution to the heat equation on a specified domain with appropriate boundary conditions. It is also one of the main tools in the study of the spectrum of the Laplace operator, and is thus of some auxiliary importance throughout mathematical physics. The heat kernel represents the evolution of temperature in a region whose boundary is held fixed at a particular temperature (typically zero), such that an initial unit of heat energy is placed at a point at time t = 0.
The most well-known heat kernel is the heat kernel of d-dimensional Euclidean space Rd, which has the form of a time-varying Gaussian function,
This solves the heat equation
for all t > 0 and x,y ∈ Rd, where Δ is the Laplace operator, with the initial condition
where δ is a Dirac delta distribution and the limit is taken in the sense of distributions. To wit, for every smooth function ϕ of compact support,
On a more general domain Ω in Rd, such an explicit formula is not generally possible. The next simplest cases of a disc or square involve, respectively, Bessel functions and Jacobi theta functions. Nevertheless, the heat kernel (for, say, the Dirichlet problem) still exists and is smooth for t > 0 on arbitrary domains and indeed on any Riemannian manifold with boundary, provided the boundary is sufficiently regular. More precisely, in these more general domains, the heat kernel for the Dirichlet problem is the
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https://en.wikipedia.org/wiki/Thomas%20K.%20Donaldson
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Thomas K. Donaldson (19442006) was a mathematician and well-known cryonics advocate. He was born in the state of Kentucky in the United States, and took his Ph.D. from the University of Chicago in 1969. He also lived in Sunnyvale, California, and for many years in Canberra, Australia, where he taught mathematics at Australian National University. He founded both the Cryonics Association of Australia and the Institute for Neural Cryobiology, which has funded ground-breaking research in cryopreservation of brain tissue.
Writings
In 1974 his monograph A Laplace Transform Calculus for Partial Differential Operators was published by the American Mathematical Society.
In 1976 Donaldson published A Brief Scientific Introduction to Cryonics, the first concise review of scientific literature supporting the practice of cryonics. He was a regular contributor to Cryonics magazine, the newsletter of the Alcor Life Extension Foundation, for many years. He also published his own periodical, Periastron, which discussed neuroscience issues as they pertain to cryonics.
Donaldson proposed some of the earliest ideas for cell repair technologies, seeing such technologies as extensions of natural biology, but using new enzymes and solvents other than water for low temperature operation. When Eric Drexler’s ideas about molecular nanotechnology came to dominate cryonics thinking in the mid-1980s, he frequently expressed concern that too much reliance was being placed on the new molecular-
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https://en.wikipedia.org/wiki/Gyroid
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A gyroid is an infinitely connected triply periodic minimal surface discovered by Alan Schoen in 1970.
It arises naturally in polymer science and biology, as an interface with high surface area.
History and properties
The gyroid is the unique non-trivial embedded member of the associate family of the Schwarz P and D surfaces.
Its angle of association with respect to the D surface is approximately 38.01°.
The gyroid is similar to the lidinoid.
The gyroid was discovered in 1970 by NASA scientist Alan Schoen.
He calculated the angle of association and gave a convincing demonstration of pictures of intricate plastic models, but did not provide a proof of embeddedness.
Schoen noted that the gyroid contains neither straight lines nor planar symmetries.
Karcher gave a different, more contemporary treatment of the surface in 1989 using conjugate surface construction.
In 1996 Große-Brauckmann and Wohlgemuth proved that it is embedded, and in 1997 Große-Brauckmann provided CMC (constant mean curvature) variants of the gyroid and made further numerical investigations about the volume fractions of the minimal and CMC gyroids.
The gyroid separates space into two oppositely congruent labyrinths of passages. The gyroid has space group I4132 (no. 214). Channels run through the gyroid labyrinths in the (100) and (111) directions; passages emerge at 70.5 degree angles to any given channel as it is traversed, the direction at which they do so gyrating down the channel, giving rise
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https://en.wikipedia.org/wiki/Environmental%20stress%20fracture
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In materials science, environmental stress fracture or environment assisted fracture is the generic name given to premature failure under the influence of tensile stresses and harmful environments of materials such as metals and alloys, composites, plastics and ceramics.
Metals and alloys exhibit phenomena such as stress corrosion cracking, hydrogen embrittlement, liquid metal embrittlement and corrosion fatigue all coming under this category. Environments such as moist air, sea water and corrosive liquids and gases cause environmental stress fracture. Metal matrix composites are also susceptible to many of these processes.
Plastics and plastic-based composites may suffer swelling, debonding and loss of strength when exposed to organic fluids and other corrosive environments, such as acids and alkalies. Under the influence of stress and environment, many structural materials, particularly the high-specific strength ones become brittle and lose their resistance to fracture. While their fracture toughness remains unaltered, their threshold stress intensity factor for crack propagation may be considerably lowered. Consequently, they become prone to premature fracture because of sub-critical crack growth. This article aims to give a brief overview of the various degradation processes mentioned above.
Stress corrosion cracking
Stress corrosion cracking is a phenomenon where a synergistic action of corrosion and tensile stress leads to brittle fracture of normally ductile mat
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https://en.wikipedia.org/wiki/Edward%20Bullard
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Sir Edward Crisp Bullard FRS (21 September 1907 – 3 April 1980) was a British geophysicist who is considered, along with Maurice Ewing, to have founded the discipline of marine geophysics. He developed the theory of the geodynamo, pioneered the use of seismology to study the sea floor, measured geothermal heat flow through the ocean crust, and found new evidence for the theory of continental drift.
Early life
Bullard was born into a wealthy brewing family in Norwich, England. He was educated at Norwich School and later studied Natural Sciences at Clare College, Cambridge. He studied under Ernest Rutherford at the Cavendish Laboratory of University of Cambridge and in the 1930s he received his PhD degree as a nuclear physicist.
As it was the Great Depression and he was married, he had to find a career to survive on. In the 1930s, nuclear physics did not seem to be it so he switched to geophysics.
In 1931, Bullard became a demonstrator in the department of geodesy and geophysics at Cambridge, which at the time of its formation in 1921 consisted of only one person, Sir Gerald Lenox-Conyngham. By himself Lenox-Conyngham was unable to do much. By 1931 he had persuaded the university that he needed help, and had been given funds for a junior post. On the advice of Rutherford he appointed Bullard to this position. At the same time Harold Jeffreys was appointed to a readership in geophysics. In the next eight years, this small group of people had a quite remarkable impact on geoph
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https://en.wikipedia.org/wiki/MRC%20Cognition%20and%20Brain%20Sciences%20Unit
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The Cognition and Brain Sciences Unit is a branch of the UK Medical Research Council, based in Cambridge, England. The CBSU is a centre for cognitive neuroscience, with a mission to improve human health by understanding and enhancing cognition and behaviour in health, disease and disorder. It is one of the largest and most long-lasting contributors to the development of psychological theory and practice.
The CBSU has its own magnetic resonance imaging (MRI, 3T) scanner on-site, as well as a 306-channel magnetoencephalography (MEG) system and a 128-channel electroencephalography (EEG) laboratory.
The CBSU has close links to clinical neuroscience research in the University of Cambridge Medical School. Over 140 scientists, students, and support staff work in research areas such as Memory, Attention, Emotion, Speech and Language, Development and Aging, Computational Modelling and Neuroscience Methods. With dedicated facilities available on site, the Unit has particular strengths in the application of neuroimaging techniques in the context of well-developed neuro-cognitive theory.
History
The unit was established in 1944 as the MRC Applied Psychology Unit. In June 2001, the History of Modern Biomedicine Research Group held a witness seminar to gather information on the unit's history.
On 1 July 2017, the CBU was merged with the University of Cambridge. Coming under the Clinical School, the unit is still funded by the British government through Research Councils UK but is man
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https://en.wikipedia.org/wiki/Slip%20%28materials%20science%29
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In materials science, slip is the large displacement of one part of a crystal relative to another part along crystallographic planes and directions. Slip occurs by the passage of dislocations on close/packed planes, which are planes containing the greatest number of atoms per area and in close-packed directions (most atoms per length). Close-packed planes are known as slip or glide planes. A slip system describes the set of symmetrically identical slip planes and associated family of slip directions for which dislocation motion can easily occur and lead to plastic deformation. The magnitude and direction of slip are represented by the Burgers vector, .
An external force makes parts of the crystal lattice glide along each other, changing the material's geometry. A critical resolved shear stress is required to initiate a slip.
Slip systems
Face centered cubic crystals
Slip in face centered cubic (fcc) crystals occurs along the close packed plane. Specifically, the slip plane is of type {111}, and the direction is of type <10>. In the diagram on the right, the specific plane and direction are (111) and [10], respectively.
Given the permutations of the slip plane types and direction types, fcc crystals have 12 slip systems. In the fcc lattice, the norm of the Burgers vector, b, can be calculated using the following equation:
Where a is the lattice constant of the unit cell.
Body centered cubic crystals
Slip in body-centered cubic (bcc) crystals occurs along the plane of s
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https://en.wikipedia.org/wiki/Pattern%20formation
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The science of pattern formation deals with the visible, (statistically) orderly outcomes of self-organization and the common principles behind similar patterns in nature.
In developmental biology, pattern formation refers to the generation of complex organizations of cell fates in space and time. The role of genes in pattern formation is an aspect of morphogenesis, the creation of diverse anatomies from similar genes, now being explored in the science of evolutionary developmental biology or evo-devo. The mechanisms involved are well seen in the anterior-posterior patterning of embryos from the model organism Drosophila melanogaster (a fruit fly), one of the first organisms to have its morphogenesis studied, and in the eyespots of butterflies, whose development is a variant of the standard (fruit fly) mechanism.
Patterns in nature
Examples of pattern formation can be found in biology, physics, and science, and can readily be simulated with computer graphics, as described in turn below.
Biology
Biological patterns such as animal markings, the segmentation of animals, and phyllotaxis are formed in different ways.
In developmental biology, pattern formation describes the mechanism by which initially equivalent cells in a developing tissue in an embryo assume complex forms and functions. Embryogenesis, such as of the fruit fly Drosophila, involves coordinated control of cell fates. Pattern formation is genetically controlled, and often involves each cell in a field sensing
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https://en.wikipedia.org/wiki/Huey%20P.%20Long%20Bridge
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Huey P. Long Bridge may refer to:
Huey P. Long Bridge (Baton Rouge), in Baton Rouge, Louisiana, United States
Huey P. Long Bridge (Jefferson Parish), in Jefferson Parish, Louisiana, United States (near New Orleans), a civil engineering landmark
See also
Long-Allen Bridge (disambiguation), for other bridges named after Louisiana governors Huey P. Long and Oscar K. Allen
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https://en.wikipedia.org/wiki/Spring%20Lake%20High%20School
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Spring Lake High School is located in Spring Lake, Michigan, in the United States, in the Spring Lake Public School District, serving grades 9-12.
Academics
SLHS offers AP courses in U.S. History, Economics, Biology, Spanish, English, and Calculus, as well as IB Courses in World History, Biology, Chemistry, Spanish, English, Calculus, and Psychology.
References
External links
Spring Lake High School Website
Public high schools in Michigan
Schools in Ottawa County, Michigan
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https://en.wikipedia.org/wiki/Charles%20Thomas%20Jackson
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Charles Thomas Jackson (June 21, 1805 – August 28, 1880) was an American physician and scientist who was active in medicine, chemistry, mineralogy, and geology.
Life and work
Born at Plymouth, Massachusetts, of a prominent New England family, he was a brother-in-law of Ralph Waldo Emerson and a graduate of the Harvard Medical School in 1829, where he won the Boylston prize for his dissertation. While at Harvard he made a geological exploration of Nova Scotia with his friend Francis Alger of Boston, which helped to increasingly turn his interests toward geology. In 1829, he traveled to Europe where he studied both medicine and geology for several years and made the acquaintance of prominent European scientists and physicians.
Upon returning to the United States he played an active role in the new state geological survey movement, serving successively between 1836 and 1844 as the state geologist of Maine, Rhode Island, and New Hampshire. In 1844–45, he was an on-site mining consultant to the Lake Superior Copper Company, one of the first companies to attempt mining the native copper deposits of Michigan's Keweenaw Peninsula on Lake Superior.
In 1847, Jackson was appointed United States Geologist for the Lake Superior land district, which was about to become one of the major copper-producing regions of the world. His leadership of that survey proved to be a disaster, and he was dismissed from his position and the completion of the survey was turned over to his assistants J
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https://en.wikipedia.org/wiki/Projection%20%28mathematics%29
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In mathematics, a projection is an idempotent mapping of a set (or other mathematical structure) into a subset (or sub-structure). In this case, idempotent means that projecting twice is the same as projecting once. The restriction to a subspace of a projection is also called a projection, even if the idempotence property is lost.
An everyday example of a projection is the casting of shadows onto a plane (sheet of paper): the projection of a point is its shadow on the sheet of paper, and the projection (shadow) of a point on the sheet of paper is that point itself (idempotency). The shadow of a three-dimensional sphere is a closed disk. Originally, the notion of projection was introduced in Euclidean geometry to denote the projection of the three-dimensional Euclidean space onto a plane in it, like the shadow example. The two main projections of this kind are:
The projection from a point onto a plane or central projection: If C is a point, called the center of projection, then the projection of a point P different from C onto a plane that does not contain C is the intersection of the line CP with the plane. The points P such that the line CP is parallel to the plane does not have any image by the projection, but one often says that they project to a point at infinity of the plane (see Projective geometry for a formalization of this terminology). The projection of the point C itself is not defined.
The projection parallel to a direction D, onto a plane or parallel projec
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https://en.wikipedia.org/wiki/Daniel%20Schwenter
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Daniel Schwenter (Schwender) (31 January 1585 – 19 January 1636) was a German Orientalist, mathematician, inventor, poet, and librarian.
Biography
Schwenter was born in Nuremberg. He was professor of oriental languages and mathematics at the University of Altdorf. This is achieved by a preface written by Schwenter in the book Kurtzer, gründtlicher, warhaffter, gebesserter und vermehrter Underricht, Zuberaitung und Gebrauch deß Circkels, Schregmeß und Linial from George Galgemair and by an old chronicle of the University of Altdorf.
His works include Delicia Physico-Mathematicae (Nuremberg, 1636) and Geometriae practicae novae et auctae tractatus I-IV (published posthumously in 1641). Among other topics, Geometriae practicae covers the art of baculometry - the measuring of inaccessible distances via staves.
As a linguist, Schwenter was familiar with Greek, Hebrew, Arabic, Syriac, and Aramaic. He was also an authority on Euclid. He died in Altdorf bei Nürnberg.
Schwenter and the Scioptric Ball
He is credited with developing the scioptric ball in 1636. This is a universal joint that allows a microscope, mounted on the ball, to be swiveled into any position. Its invention was inspired by Schwenter's studies of the human eye. The scioptric ball provided a firm anchor for a microscope or telescope while allowing the telescope to be swiveled in all directions in order to follow the course of an eclipse or for drawing panoramic views. The microscope or telescope passes t
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https://en.wikipedia.org/wiki/Multiple%20%28mathematics%29
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In mathematics, a multiple is the product of any quantity and an integer. In other words, for the quantities a and b, it can be said that b is a multiple of a if b = na for some integer n, which is called the multiplier. If a is not zero, this is equivalent to saying that is an integer.
When a and b are both integers, and b is a multiple of a, then a is called a divisor of b. One says also that a divides b. If a and b are not integers, mathematicians prefer generally to use integer multiple instead of multiple, for clarification. In fact, multiple is used for other kinds of product; for example, a polynomial p is a multiple of another polynomial q if there exists third polynomial r such that p = qr.
Examples
14, 49, −21 and 0 are multiples of 7, whereas 3 and −6 are not. This is because there are integers that 7 may be multiplied by to reach the values of 14, 49, 0 and −21, while there are no such integers for 3 and −6. Each of the products listed below, and in particular, the products for 3 and −6, is the only way that the relevant number can be written as a product of 7 and another real number:
is not an integer;
is not an integer.
Properties
0 is a multiple of every number ().
The product of any integer and any integer is a multiple of . In particular, , which is equal to , is a multiple of (every integer is a multiple of itself), since 1 is an integer.
If and are multiples of then and are also multiples of .
Submultiple
In some texts, "a is a su
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https://en.wikipedia.org/wiki/Aleksey%20Letnikov
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Aleksey Vasilyevich Letnikov (, 1837–1888) was a Russian mathematician.
After graduating from the Konstantinovsky Land-Surveying Institute () in Moscow, Letnikov attended classes at Moscow University and the Sorbonne. In 1860 he became an Instructor of Mathematics at the Konstantinovsky Institute. He obtained the degrees of Master and Ph.D. from Moscow University in 1868 and 1874 respectively.
In 1868 Letnikov became a professor at the Imperial Moscow Technical School and from 1879 to 1880 was an Inspector at the school. From 1883 he was the principal of the Aleksandrov Commercial School (, currently The State University of Management) and from 1884 he was a Corresponding Member of the Russian Academy of Sciences.
His most renowned contribution to mathematics was the creation of the Grünwald–Letnikov derivative. He also published results in the fields of analytic geometry, ordinary differential equations, and non-Euclidean geometry.
Letnikov died in Moscow in 1888 and was buried in the cemetery of the Novo-Alekseyevsky Monastery..
References
"Letnikov" in the Brockhaus and Efron Encyclopedic Dictionary
Letnikov
Letnikov
Corresponding members of the Saint Petersburg Academy of Sciences
Moscow State University alumni
Letnikov
Letnikov
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https://en.wikipedia.org/wiki/Sufetula
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Sufetula may refer to:
places and jurisdictions
an ancient city, whose Roman ruins are in Sbeitla, in modern Tunisia
its former Roman diocese Sufetula (see), now a Catholic titular bishopric
biology
Sufetula (moth), a moth genus
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https://en.wikipedia.org/wiki/Sam%20Treiman
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Sam Bard Treiman (; May 27, 1925 – November 30, 1999) was an American theoretical physicist who produced research in the fields of cosmic rays, quantum physics, plasma physics, and gravity physics. He made contributions to the understanding of the weak interaction and he and his students are credited with developing the so-called standard model of elementary particle physics. He was a Higgins professor of physics at Princeton University, a member of the National Academy of Sciences and member of the JASON Defense Advisory Group. He was a student of Enrico Fermi and John Alexander Simpson Jr. Treiman published articles on quantum mechanics, plasmas, gravity theory, condensed matter and the history of physics.
Background
Treiman's parents, Abraham and Sarah, were Jewish immigrants from Eastern Europe who emigrated to Chicago. Sam had a brother, Oscar, who was six years older. Sam was educated in the Chicago public school system and, after graduating high school in 1942, he entered Northwestern University, electing to study chemical engineering. After two years at Northwestern he joined the navy, training as a radar repair technician and he spent the last year of the war as a petty officer in the Philippines, doing, in his words, "a prodigious amount of reading in the peaceful jungles - novels and science". After the war he went to the University of Chicago, receiving a B.S. (1949) and M.S. (1950), having changed his major to physics. He received an Atomic Energy Commission p
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https://en.wikipedia.org/wiki/Sverdrup%20%26%20Parcel
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Sverdrup & Parcel was an American civil engineering company formed in 1928 by Leif J. Sverdrup and his college engineering professor John I. Parcel. The company worked primarily in a specialty field of bridges. The company's headquarters was located in St. Louis, Missouri.
The firm was the designer of the ill-fated I-35W Mississippi River bridge, Minneapolis, Minnesota, 1964 (collapsed on August 1, 2007). The official report by the National Transportation Safety Board blamed the bridge collapse on a design error by the firm, resulting in the gusset plates having inadequate load capacity.
Some other well-known projects of Sverdrup & Parcel include:
Amelia Earhart Bridge 1939, Atchison, Kansas
Sidney Lanier Bridge 1956, Brunswick, Georgia
Bridge of the Americas 1962 (also known as Puente de las Américas, Thatcher Ferry Bridge), Panama, crosses the Panama Canal
Chesapeake Bay Bridge-Tunnel, (also known as Lucius J. Kellam, Jr. Bridge-Tunnel) completed in 1964, and named one of the "Seven Engineering Wonders of the Modern World" shortly thereafter.
Busch Memorial Stadium 1966, St. Louis, Missouri
Angostura Bridge 1967, Bolivar, Venezuela, crosses the Orinoco River
Hearnes Center 1972, Columbia, Missouri
Louisiana Superdome 1975, New Orleans, Louisiana
Monitor-Merrimac Memorial Bridge-Tunnel 1992, in Newport News, Virginia
Sverdrup & Parcel was succeeded by Sverdrup Civil, which in 1999 was part of the merger between Sverdrup and Jacobs Engineering.
References
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https://en.wikipedia.org/wiki/Leon%20O.%20Jacobson
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Dr. Leon Orris Jacobson (December 16, 1911 – September 20, 1992) was an American physician, hematologist, radiologist and medical researcher.
He was professor emeritus of biology and medicine at the University of Chicago and made notable contributions to the study of radiology and hematology, with major impacts on chemotherapy and radiotherapy.
Biography
Leon Orris Jacobson was born in Sims, North Dakota. In 1935, Jacobson graduated from North Dakota State University and from the University of Chicago medical school in 1939. In 1942, he joined the staff of the Manhattan Project at the University of Chicago. From 1945, Jacobson worked as an assistant professor of medicine at the University of Chicago.
In 1951, Jacobson joined the staff of Argonne Cancer Research Hospital, now known as the Franklin McLean Memorial Research Institute, as professor of Medicine and head of hematology. In 1961, Jacobson became the chairman of the University of Chicago Department of Medicine.
Jacobson was elected to the National Academy of Sciences (1965), American Academy of Arts and Sciences (1967), and Institute of Medicine (1970). He was a recipient of the Theodore Roosevelt Rough Rider Award (1976). Leon Jacobson died at the University of Chicago Hospital on September 18, 1992.
References
Other sources
Goldwasser, Eugene "Jake. Leon O. Jacobson, M.D. The life and work of a distinguished medical scientist," Science History Publications, 2006. .
Atomic Heritage Foundation. Leon O
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https://en.wikipedia.org/wiki/WFO
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WFO may refer to:
Well-founded ordering, in mathematics, see well-founded relation
W.F.O. (album), a 1994 album by the thrash metal band Overkill
Workforce optimization, strategy for managing contact center staffing, processes, and workflows.
Weather Forecast Office, a local forecasting and warning office of the United States National Weather Service: See List of National Weather Service Weather Forecast Offices
Washington Field Office, of the United States Secret Service
Washington Field Office, of the Federal Bureau of Investigation
World Flora Online
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https://en.wikipedia.org/wiki/Colin%20Wood
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Colin Arthur Wood (born 15 June 1943) is a British musician engaged in the field of jazz and rock music.
Wood was born in Camberwell, South East London, & was moved to Somerset in 1950. He played jazz piano while still at school. In 1962 he went to Durham University to study mathematics. In 1965 he moved to London to play with Bill Nile's Delta Jazz Band and with Monty Sunshine (1968). He was also playing on rock sessions with The Yardbirds, David Bowie, Cat Stevens, Kevin Coyne and was the keyboardist on two songs included as part of the debut album of Uriah Heep. Wood, whose other musical talents also include playing the flute, did not, however (although offered the job), become an official member of the band. He lectured in maths for a time while freelancing musically. In September 1977 he joined Acker Bilk and remained with him into the 2000s.
Discography
With Uriah Heep
Very 'eavy... Very 'umble (1970)
With Siren
Siren
With Chris Barber / Kenny Ball / Acker Bilk
The Ultimate
Any with Acker's Paramount Jazz Band since 1978
References
John Chilton: Who's who of British Jazz London: Continuum 2004; (2nd ed.)
External links
Colin Wood at The Milarus Mansion
1943 births
Living people
Musicians from Camberwell
British rock keyboardists
British jazz keyboardists
Uriah Heep (band) members
Alumni of Grey College, Durham
Suns of Arqa members
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https://en.wikipedia.org/wiki/Lyndon%20word
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In mathematics, in the areas of combinatorics and computer science, a Lyndon word is a nonempty string that is strictly smaller in lexicographic order than all of its rotations. Lyndon words are named after mathematician Roger Lyndon, who investigated them in 1954, calling them standard lexicographic sequences. Anatoly Shirshov introduced Lyndon words in 1953 calling them regular words. Lyndon words are a special case of Hall words; almost all properties of Lyndon words are shared by Hall words.
Definitions
Several equivalent definitions exist.
A -ary Lyndon word of length is an -character string over an alphabet of size , and which is the unique minimum element in the lexicographical ordering in the multiset of all its rotations. Being the singularly smallest rotation implies that a Lyndon word differs from any of its non-trivial rotations, and is therefore aperiodic.
Alternately, a word is a Lyndon word if and only if it is nonempty and lexicographically strictly smaller than any of its proper suffixes, that is for all nonempty words such that and is nonempty.
Another characterisation is the following: A Lyndon word has the property that it is nonempty and, whenever it is split into two nonempty substrings, the left substring is always lexicographically less than the right substring. That is, if is a Lyndon word, and is any factorization into two substrings, with and understood to be non-empty, then . This definition implies that a string of length is a Ly
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https://en.wikipedia.org/wiki/Remineralisation
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In biogeochemistry, remineralisation (or remineralization) refers to the breakdown or transformation of organic matter (those molecules derived from a biological source) into its simplest inorganic forms. These transformations form a crucial link within ecosystems as they are responsible for liberating the energy stored in organic molecules and recycling matter within the system to be reused as nutrients by other organisms.
Remineralisation is normally viewed as it relates to the cycling of the major biologically important elements such as carbon, nitrogen and phosphorus. While crucial to all ecosystems, the process receives special consideration in aquatic settings, where it forms a significant link in the biogeochemical dynamics and cycling of aquatic ecosystems.
Role in biogeochemistry
The term "remineralization" is used in several contexts across different disciplines. The term is most commonly used in the medicinal and physiological fields, where it describes the development or redevelopment of mineralized structures in organisms such as teeth or bone. In the field of biogeochemistry, however, remineralization is used to describe a link in the chain of elemental cycling within a specific ecosystem. In particular, remineralization represents the point where organic material constructed by living organisms is broken down into basal inorganic components that are not obviously identifiable as having come from an organic source. This differs from the process of decomposit
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https://en.wikipedia.org/wiki/Zero%20suppression
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Zero suppression is the removal of redundant zeroes from a number. This can be done for storage, page or display space constraints or formatting reasons, such as making a letter more legible.
Examples
00049823 → 49823
7.678600000 → 7.6786
0032.3231000 → 32.3231
2.45000×1010 → 2.45×1010
0.0045×1010 → 4.5×107
One must be careful; in physics and related disciplines, trailing zeros are used to indicate the precision of the number, as an error of ±1 in the last place is assumed. Examples:
4.5981 is 4.5981 ± 0.0001
4.59810 is 4.5981 ± 0.00001
4.598100 is 4.5981 ± 0.000001
Data compression
It is also a way to store a large array of numbers, where many of the entries are zero. By omitting the zeroes, and instead storing the indices along with the values of the non-zero items, less space may be used in total. It only makes sense if the extra space used for storing the indices (on average) is smaller than the space saved by not storing the zeroes. This is sometimes used in a sparse array.
Example:
Original array: 0, 1, 0, 0, 2, 5, 0, 0, 0, 4, 0, 0, 0, 0, 0
Pairs of index and data: {2,1}, {5,2}, {6,5}, {10,4}
See also
References
Information theory
0 (number)
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https://en.wikipedia.org/wiki/Transfer%20learning
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Transfer learning (TL) is a technique in machine learning (ML) in which knowledge learned from a task is re-used in order to boost performance on a related task. For example, for image classification, knowledge gained while learning to recognize cars could be applied when trying to recognize trucks. This topic is related to the psychological literature on transfer of learning, although practical ties between the two fields are limited. Reusing/transferring information from previously learned tasks to new tasks has the potential to significantly improve learning efficiency.
History
In 1976, Bozinovski and Fulgosi published a paper addressing transfer learning in neural network training. The paper gives a mathematical and geometrical model of the topic. In 1981, a report considered the application of transfer learning to a dataset of images representing letters of computer terminals, experimentally demonstrating positive and negative transfer learning.
In 1993, Pratt formulated the discriminability-based transfer (DBT) algorithm.
In 1997, Pratt and Thrun guest-edited a special issue of Machine Learning devoted to transfer learning, and by 1998, the field had advanced to include multi-task learning, along with more formal theoretical foundations. Learning to Learn, edited by Thrun and Pratt, is a 1998 review of the subject.
Transfer learning has been applied in cognitive science. Pratt guest-edited an issue of Connection Science on reuse of neural networks through transfer
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https://en.wikipedia.org/wiki/Q-derivative
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In mathematics, in the area of combinatorics and quantum calculus, the q-derivative, or Jackson derivative, is a q-analog of the ordinary derivative, introduced by Frank Hilton Jackson. It is the inverse of Jackson's q-integration. For other forms of q-derivative, see .
Definition
The q-derivative of a function f(x) is defined as
It is also often written as . The q-derivative is also known as the Jackson derivative.
Formally, in terms of Lagrange's shift operator in logarithmic variables, it amounts to the operator
which goes to the plain derivative, as .
It is manifestly linear,
It has a product rule analogous to the ordinary derivative product rule, with two equivalent forms
Similarly, it satisfies a quotient rule,
There is also a rule similar to the chain rule for ordinary derivatives. Let . Then
The eigenfunction of the q-derivative is the q-exponential eq(x).
Relationship to ordinary derivatives
Q-differentiation resembles ordinary differentiation, with curious differences. For example, the q-derivative of the monomial is:
where is the q-bracket of n. Note that so the ordinary derivative is regained in this limit.
The n-th q-derivative of a function may be given as:
provided that the ordinary n-th derivative of f exists at x = 0. Here, is the q-Pochhammer symbol, and is the q-factorial. If is analytic we can apply the Taylor formula to the definition of to get
A q-analog of the Taylor expansion of a function about zero follows:
Higher order q-deriva
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https://en.wikipedia.org/wiki/Remotely%20triggered%20earthquakes
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Remotely triggered earthquakes are a result of the effects of large earthquakes at considerable distance, outside of the immediate aftershock zone. The farther one gets from the initiating earthquake in both space and time, the more difficult it is to establish an association.
The physics of triggering an earthquake are complex. Most earthquake-generating zones are in a state of being close to failure. If such a zone were to be left completely alone, it would generate significant earthquakes spontaneously. Remote earthquakes, however, are in a position to disturb this critical state, either by shifting the stresses statically, or by dynamic change caused by passing seismic waves.
The first type of triggering may be due to static changes in the critical state. For example, after the magnitude 7.3 Landers earthquake struck California in 1992, it is said that "the earthquake map of California lit up like a Christmas tree". This event reinforced the idea of remotely triggered earthquakes, and pushed the hypothesis into the scientific mainstream. Following the very large 2004 Indian Ocean earthquake, it was established that remote earthquakes had been triggered as far away as Alaska.
There is scientific evidence for a "long reach", mainly in the form of discrete element modelling used in the mining industry. If rock is modeled as discrete elements in a critical state, a single disturbance can influence a wide area. A smaller-scale example is when a small excavation in a valle
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https://en.wikipedia.org/wiki/Pyranose
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In organic chemistry, pyranose is a collective term for saccharides that have a chemical structure that includes a six-membered ring consisting of five carbon atoms and one oxygen atom (a heterocycle). There may be other carbons external to the ring. The name derives from its similarity to the oxygen heterocycle pyran, but the pyranose ring does not have double bonds. A pyranose in which the anomeric (hydroxyl group) at C(l) has been converted into an OR group is called a pyranoside.
Formation
The pyranose ring is formed by the reaction of the hydroxyl group on carbon 5 (C-5) of a sugar with the aldehyde at carbon 1. This forms an intramolecular hemiacetal. If reaction is between the C-4 hydroxyl and the aldehyde, a furanose is formed instead. The pyranose form is thermodynamically more stable than the furanose form, which can be seen by the distribution of these two cyclic forms in solution.
History
Hermann Emil Fischer won the Nobel Prize in Chemistry (1902) for his work in determining the structure of the D-aldohexoses. However, the linear, free-aldehyde structures that Fischer proposed represent a very minor percentage of the forms that hexose sugars adopt in solution. It was Edmund Hirst and Clifford Purves, in the research group of Walter Haworth, who conclusively determined that the hexose sugars preferentially form a pyranose, or six-membered, ring. Haworth drew the ring as a flat hexagon with groups above and below the plane of the ring – the Haworth projectio
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https://en.wikipedia.org/wiki/Arthur%20Pardee
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Arthur Beck Pardee (July 13, 1921 – February 24, 2019) was an American biochemist. One biographical portrait begins "Among the titans of science, Arthur Pardee is especially intriguing." There is hardly a field of molecular biology that is not affected by his work, which has advanced our understanding through theoretical predictions followed by insightful experiments. He is perhaps most famous for his part in the 'PaJaMo experiment' of the late 1950s, which greatly helped in the discovery of messenger RNA. He is also well known as the discoverer of the restriction point, in which a cell commits itself to certain cell cycle events during the G1 cycle. He did a great deal of work on tumor growth and regulation, with a particular focus on the role of estrogen in hormone-responsive tumors. He is also well known for the development of various biochemical research techniques, most notably the differential display methodology, which is used in examining the activation of genes in cells. More recently he championed the acceptance and adoption of the conceptual review as a valuable approach to unearthing new knowledge from the enormous stores of information in the scientific literature. He died in February 2019 at the age of 97.
Career
Pardee received his Bachelor of Science degree from the University of California, Berkeley in 1942 while his Master's (1943) and PhD (1947) degrees were earned at the California Institute of Technology under the mentorship of Linus Pauling, whom he co
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https://en.wikipedia.org/wiki/John%20Tedder%2C%202nd%20Baron%20Tedder
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John Michael Tedder, 2nd Baron Tedder, FRSE FRSC (4 July 1926 – 18 February 1994), was the Purdie Professor of Chemistry at St. Andrews University, Scotland.
Early life and education
He was born in London on 4 July 1926, the second born son of Arthur William Tedder and Rosalinde Maclardy. His father had a military career in the Royal Air Force, that culminated in his becoming Marshal of the Royal Air Force. As his father's military appointments involved frequent changes, the Tedder family's residences also shifted. He attended schools in Surrey, Whitgift School (1934–36), Sumatra in Indonesia (1936–38) and Dauntsey's School in Wiltshire (1938–44). He suffered with disabilities in both hearing and eyesight, and was rejected as a candidate for military service in the Second World War.
Tedder's early life was shaped by two significant tragedies. His older brother Dick was killed on active service in France in 1940. His mother, Rosalinde Tedder, died in January 1943 in an air crash in Egypt. His father was a witness to the air crash and was deeply affected by the death of his wife.
As Tedder was unfit to serve in military action, in 1944 he went to university to study chemistry. He studied at Magdalene College, University of Cambridge for his undergraduate degree and, owing to the impact of the family tragedies, initially obtained poor grades. However, he persisted and was awarded a degree (B.A.) in 1947. He received encouragement from some of his lecturers and went on to rece
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https://en.wikipedia.org/wiki/Gene%20editing
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Gene editing may refer to:
Genetic engineering of any organism by genome editing. Gene editing is the emerging molecular biology technique which makes very specific targeted changes by insertion, deletion or substitution of genetic material in an organism's DNA to obtain desired results. Examples of gene editing are CRISPR, zinc finger nuclease, transcription activator-like effector nuclease (TALEN), oligonucleotide directed mutagenesis + meganucleases.
Genome editing, a type of genetic engineering
Gene therapy, the therapeutic delivery of nucleic acid polymers into a patient's cells as a drug to treat disease
CRISPR gene editing, a genetic engineering technique.CRISPR are termed as (site directed nucleases) SDN since they target specific part of genome, there are 3 different categories of SDN. SDN1 makes random mutations at target site to repair the damaged host DNA without involving any foreign DNA. SDN2 uses small non coding homologous repair DNA to achieve specific nucleotide sequence to repair the host DNA by (homology directed repair) HDR which is a natural nucleic acid repair system. SDN3 uses a large stretch of protein coding donor DNA which is targeted for insertion through HDR at a predefined genomic locus.
TALEN editing, using transcription activator-like effector nucleases. TALENs are another type of genome editing tool. They work by using engineered proteins that can recognize and bind to specific DNA sequences, which then triggers a cut in the DNA. TALENs are
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https://en.wikipedia.org/wiki/Deme%20%28biology%29
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In biology, a deme, in the strict sense, is a group of individuals that belong to the same taxonomic group. However, when biologists, and especially ecologists, use the term ‘deme’ they usually refer to it as the definition of a gamodeme: a local group of individuals (from the same taxon) that interbreed with each other and share a gene pool. The latter definition of a deme is only applicable to sexual reproducing species, while the former is more neutral and also takes asexual reproducing species into account, such as certain plant species. In the following sections the latter (and most frequently used) definition of a deme will be used.
In evolutionary computation, a "deme" often refers to any isolated subpopulation subjected to selection as a unit rather than as individuals.
Local adaptation
A population of a species usually has multiple demes. Environments between these demes can differ. Demes could, therefore, become locally adapted to their environment. A good example of this is the Adaptive Deme Formation (ADF) hypothesis in insects. The ADF hypothesis states that herbivorous insects can become adapted to specific host plants in their local environment because local plants can have unique nutrient patches to which insects may become adapted. This hypothesis predicts that less mobile insect demes are more likely to become locally adapted than more dispersive insect. However, a meta-analysis, based on 17 studies on this subject, showed that dispersive insect demes wer
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https://en.wikipedia.org/wiki/FFT%20%28disambiguation%29
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A fast Fourier transform is a numerical algorithm used in signal processing.
FFT may also refer to:
Games
Final Fantasy Tactics, a video game
A Fistful of TOWs, a miniatures wargame
Fédération Française de Tarot, the French tarot federation
Sport
Fédération Française de Tennis, the French Tennis Federation
Firefighters Upsala CK, a Swedish cycling team
Football Federation Tasmania, a football organisation in Australia
Four Four Two (4-4-2), a football formation
FourFourTwo, a football magazine
FourFourTwo (TV series), an Asian football TV series
4-4-2, a band formed to record the song "Come on England" for the England football team for the Euro 2004 championship
Tajikistan Football Federation (Tajik: )
Science and technology
2,1-fructan:2,1-fructan 1-fructosyltransferase
Faculty of Food Technology, Latvia University of Agriculture
Final-Form Text, part of IBM's Document Control Architecture
Future Fibre Technologies, an Australian fibre optic company
Faecal (or fecal) flotation test, a method used in veterinary parasitology to detect helminth eggs in faecal samples
United States aviation
Frontier Airlines
Capital City Airport (Kentucky)
Other uses
See also
Finite Fourier transform (disambiguation)
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https://en.wikipedia.org/wiki/Rotation%20number
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In mathematics, the rotation number is an invariant of homeomorphisms of the circle.
History
It was first defined by Henri Poincaré in 1885, in relation to the precession of the perihelion of a planetary orbit. Poincaré later proved a theorem characterizing the existence of periodic orbits in terms of rationality of the rotation number.
Definition
Suppose that is an orientation-preserving homeomorphism of the circle Then may be lifted to a homeomorphism of the real line, satisfying
for every real number and every integer .
The rotation number of is defined in terms of the iterates of :
Henri Poincaré proved that the limit exists and is independent of the choice of the starting point . The lift is unique modulo integers, therefore the rotation number is a well-defined element of Intuitively, it measures the average rotation angle along the orbits of .
Example
If is a rotation by (where ), then
and its rotation number is (cf. irrational rotation).
Properties
The rotation number is invariant under topological conjugacy, and even monotone topological semiconjugacy: if and are two homeomorphisms of the circle and
for a monotone continuous map of the circle into itself (not necessarily homeomorphic) then and have the same rotation numbers. It was used by Poincaré and Arnaud Denjoy for topological classification of homeomorphisms of the circle. There are two distinct possibilities.
The rotation number of is a rational number (in the lowes
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https://en.wikipedia.org/wiki/Franz%20Leopold%20Sonnenschein
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Franz Leopold Sonnenschein (13 July 1817 – 26 February 1879) was a German chemist from Cologne.
He taught himself pharmacy, and in the 1830s, established a small laboratory in Berlin. He worked with a physician as tutor for pharmacy students, readying them for their final exams. At the same time, he studied chemistry and in 1852 obtained his habilitation. He dedicated himself to analytic chemistry and involved himself in practical activities, for which he gained prestige. Many technical enterprises owed their success to him. He promoted analytic and judicial chemistry by numerous scientific investigations. From 1869 up until his death, he served as a professor at the University of Berlin.
Sonnenschein's reagent (phosphomolybdenic acid) is a reagent for alkaloids.
Published works
His most notable works include:
Anleitung zur chemischen Analyse ("Guide for Chemical Analysis") (1852).
Anleitung zur quantitativen chemischen Analyse ("Guide for Quantitative Chemical Analysis") (1864).
Handbuch der analytischen Chemie ("Manual of Analytic Chemistry") (1870–71).
F.L. Sonnenschein's Handbuch der gerichtlichen chemie (new edition by Alexander Classen, 1881) ("Sonnenschein's manual of forensic chemistry").
References
1817 births
1879 deaths
19th-century German chemists
German forensic scientists
Scientists from Cologne
Scientists from the Rhine Province
Academic staff of the Humboldt University of Berlin
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https://en.wikipedia.org/wiki/Biomodeling
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Biomodeling may refer to:
Mathematical Biology - the scientific discipline of building advanced mathematical models of biochemical systems thanks to advances in computer power and quantitative methods.
Biomedical modeling - the process of building complex 3D models of body parts through a computer imaging process which allows for perfectly shaped acrylic or titanium inserts to be constructed to replace broken bones or other body parts.
BioModels Database - an online database of annotated open biological models, written in Systems Biology Markup Language (SBML)
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https://en.wikipedia.org/wiki/Biocybernetics
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Biocybernetics is the application of cybernetics to biological science disciplines such as neurology and multicellular systems. Biocybernetics plays a major role in systems biology, seeking to integrate different levels of information to understand how biological systems function. The field of cybernetics itself has origins in biological disciplines such as neurophysiology. Biocybernetics is an abstract science and is a fundamental part of theoretical biology, based upon the principles of systemics. Biocybernetics is a psychological study that aims to understand how the human body functions as a biological system and performs complex mental functions like thought processing, motion, and maintaining homeostasis.(PsychologyDictionary.org)Within this field, many distinct qualities allow for different distinctions within the cybernetic groups such as humans and insects such as beehives and ants. Humans work together but they also have individual thoughts that allow them to act on their own, while worker bees follow the commands of the queen bee. (Seeley, 1989). Although humans often work together, they can also separate from the group and think for themselves.(Gackenbach, J. 2007) A unique example of this within the human sector of biocybernetics would be in society during the colonization period, when Great Britain established their colonies in North America and Australia. Many of the traits and qualities of the mother country were inherited by the colonies, as well as niche q
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https://en.wikipedia.org/wiki/Cheong%20Liew
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Cheong Liew (born 1949) is a Malaysian-born Australian chef. He moved from Malaysia to Australia in 1969 to study electrical engineering, but instead became a chef.
Early life
Cheong Liew was born in 1949 in Kuala Lumpur, Malaysia. His father was a farmer who also owned several restaurants. Following the 13 May incident, Liew's family emigrated to Adelaide, South Australia. In Adelaide, Liew's passion for cooking was ignited while he tended the grill part-time at the Greek restaurant Iliad in Whitmore Square. Although he had planned to study electrical engineering in Melbourne, he eventually decided to become a self-taught chef.
Career
In 1975, Liew opened his own restaurant Neddy's, whose menu consisted of mostly Malaysian and Chinese dishes. His cooking incorporated ingredients not commonly used during his time, such as crocodile tail, pork leg, sea urchin and shark lip. The restaurant closed in 1988 and Liew went on to teach cookery at Regency Park, Adelaide.
In 1995, Liew took the reins at The Grange restaurant at the Hilton Hotel in Adelaide. At The Grange, Liew came up his "signature dish", titled "Four Dancers of the Sea", featuring "four varieties of seafood cooked in four distinct national styles". In 2009, after some 14 years, Cheong left The Grange; the restaurant closed at the end of the year.
Awards and honours
Described as "one of the indisputable fathers of Australian cooking" by Stephen Downes in To Die For (2006), Liew was awarded the Medal of the Order
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https://en.wikipedia.org/wiki/Alexandru%20Or%C4%83scu
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Alexandru Hristea Orăscu (30 July 1817 – 16 December 1894) was a Romanian architect famous for his Neoclassicist and Renaissance-revival works.
He was born in Bucharest in 1817 to serdar Hristea Orăscu and his wife, Elena Orăscu. He graduated from the Saint Sava High School in his native city. Upon recommendation from his mathematics teacher, Petrache Poenaru, Orăscu was hired in 1837 as aide to the chief architect of the city, a job he held until 1841. He then studied architecture in Berlin and Munich, obtaining his architect diploma in 1847.
He designed the initial building of the University of Bucharest (1837–1869), the Grand Hôtel du Boulevard in Bucharest (1865–1871), the Metropolitan Cathedral in Iași (1880–1887), the boys' gymnasium in Ploiești (1865–1866), the Carol I Hotel in Constanța (1879), and the Domnița Bălașa Church in Bucharest (1881–1885).
Orăscu was the president of the Romanian Architects’ Society, and served as rector of the University of Bucharest from 1885 to 1892. He died in Bucharest in 1894.
Streets in Sector 5 of Bucharest, Cisnădie, and Sibiu bear his name.
References
External links
Orăscu as mathematician
Architecture in Romania
1817 births
1894 deaths
Architects from Bucharest
Saint Sava National College alumni
19th-century Romanian architects
Rectors of the University of Bucharest
Academic staff of the University of Bucharest
Romanian Ministers of Culture
Romanian Ministers of Education
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https://en.wikipedia.org/wiki/Herman%20Lukoff
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Herman Lukoff (May 2, 1923 – September 24, 1979) was a computer pioneer and fellow of the IEEE.
Formative years
Lukoff was born in Philadelphia, Pennsylvania to Aaron and Anna (Slemovitz) Lukoff. He graduated from the Moore School of Electrical Engineering at the University of Pennsylvania in 1943. While at the Moore School, he helped to develop the ENIAC and EDVAC computers.
Lukoff subsequently followed ENIAC co-inventors J. Presper Eckert and John W. Mauchly to their newly formed Electronic Control Company, which became Eckert-Mauchly Computer Corporation, and then became part of Remington Rand in 1950 and Sperry Corporation in 1955. He also assisted Eckert and Mauchly with the development of the UNIVAC computer and was chief engineer of the UNIVAC LARC from 1955 to 1961. He stayed with the company until his death.
Death and interment
Lukoff died of leukemia on September 24, 1979, at Bryn Mawr Hospital in Bryn Mawr, Pennsylvania. At the time of his death, he lived in Fort Washington. Interred at Shalom Memorial Park in Huntingdon Valley, Pennsylvania, he was survived by his wife, Shirley Rosner Lukoff; his three sons, Arthur, Barry, and Andrew; and his daughter, Carol.
Publications
Lukoff's memoir, From Dits to Bits, details his experiences as a first-hand observer of the birth of the computer industry.
References
Further reading
https://archives.upenn.edu/collections/finding-aid/upt50l694
http://doi.ieeecomputersociety.org/10.1109/MAHC.1980.10030
http://www.smart
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https://en.wikipedia.org/wiki/Biocomputing
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Biocomputing may refer to:
Biological computing, systems of biologically derived molecules that perform computational processes
DNA computing, a form of biological computing that uses DNA
Bioinformatics, the application of statistics and computer science to the field of molecular biology
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https://en.wikipedia.org/wiki/Schreier%20vector
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In mathematics, especially the field of computational group theory, a Schreier vector is a tool for reducing the time and space complexity required to calculate orbits of a permutation group.
Overview
Suppose G is a finite group with generating sequence which acts on the finite set . A common task in computational group theory is to compute the orbit of some element under G. At the same time, one can record a Schreier vector for . This vector can then be used to find an element satisfying , for any . Use of Schreier vectors to perform this requires less storage space and time complexity than storing these g explicitly.
Formal definition
All variables used here are defined in the overview.
A Schreier vector for is a vector such that:
For (the manner in which the are chosen will be made clear in the next section)
for
Use in algorithms
Here we illustrate, using pseudocode, the use of Schreier vectors in two algorithms
Algorithm to compute the orbit of ω under G and the corresponding Schreier vector
Input: ω in Ω,
for i in { 0, 1, …, n }:
set v[i] = 0
set orbit = { ω }, v[ω] = −1
for α in orbit and i in { 1, 2, …, r }:
if is not in orbit:
append to orbit
set
return orbit, v
Algorithm to find a g in G such that ωg = α for some α in Ω, using the v from the first algorithm
Input: v, α, X
if v[α] = 0:
return false
set g = e, and k = v[α] (where e is the identity element of G)
while k ≠ −1:
set
return g
References
Computational group theory
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https://en.wikipedia.org/wiki/ALU
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By:Aditi Jha
ALU, Alu or alu may refer to:
Computing and science
Computing
Arithmetic logic unit, a digital electronic circuit
Biology
Alu sequence, a type of short stretch of DNA
Arthrobacter luteus, a bacterium
Organizations
Abraham Lincoln University, Los Angeles, California, USA
African Leadership University
Alcatel-Lucent, a telecommunications equipment company
Amazon Labor Union
American Labor Union
Army Logistics University, Fort Lee, Virginia, USA
Sarajevo Academy of Fine Arts (Bosnian: Akademija likovnih umjetnosti Sarajevo, acronym: ALU)
People
Andrea Alù, a scientist
Jake Alu, professional baseball player
Alu (musician), Los Angeles, US
Places
Villages and boroughs
Alu, Ardabil, a village in Iran
Alu, Mazandaran, a village in Iran
Alu, Estonia, a small borough in Rapla Parish, Rapla County
Alu, Pärnu County, a village in Pärnu, Pärnu County, Estonia
Volcanoes
Alu (Ethiopia)
Alu, Sulu, Philippines
Other
Alû, the Mesopotamian demon of night
Alu (runic), in Germanic paganism
See also
Aloo (disambiguation)
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https://en.wikipedia.org/wiki/Mops
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Mops or MOPS may refer to:
More than one mop (plural noun); a form of the verb "to mop"
MOPS, or 3-(N-morpholino)propanesulfonic acid, a buffer in protein chemistry
MoPS, the UK government's Manual of Protective Security, superseded by the Security Policy Framework
Mops (genus), a genus of free-tailed bat
The Mops, a Japanese rock group
Mean of Platts Singapore, a measure of fuel oil pricing in Singapore
MOPS International (Mothers of Preschoolers), an international organization
Minimum operational performance standards, see Traffic collision avoidance system
See also
µops, an abbreviation for Micro-operation
MOP (disambiguation)
Weighted million operations per second (WMOPS), see Instructions per second
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https://en.wikipedia.org/wiki/Deterministic%20automaton
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In computer science, a deterministic automaton is a concept of automata theory where the outcome of a transition from one state to another is determined by the input.
A common deterministic automaton is a deterministic finite automaton (DFA) which is a finite state machine where for each pair of state and input symbol there is one and only one transition to a next state. DFAs recognize the set of regular languages and no other languages.
A standard way to build a deterministic finite automaton from a nondeterministic finite automaton is the powerset construction.
References
Automata (computation)
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https://en.wikipedia.org/wiki/Marcus%20du%20Sautoy
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Marcus Peter Francis du Sautoy (; born 26 August 1965) is a British mathematician, Simonyi Professor for the Public Understanding of Science at the University of Oxford, Fellow of New College, Oxford and author of popular mathematics and popular science books. He was previously a fellow of All Souls College, Oxford, Wadham College, Oxford and served as president of the Mathematical Association, an Engineering and Physical Sciences Research Council (EPSRC) senior media fellow, and a Royal Society University Research Fellow.
In 1996, he was awarded the title of distinction of Professor of Mathematics.
Education and early life
Du Sautoy was born in London to Bernard du Sautoy, employed in the computer industry, and Jennifer ( Deason) du Sautoy, who left the Foreign Office to raise her children. He grew up in Henley-on-Thames. His grandfather, Peter du Sautoy, was chairman of the publisher Faber and Faber, and managed the estates of James Joyce and Samuel Beckett.
Du Sautoy was educated at Gillotts Comprehensive School and King James's Sixth Form College (now Henley College) and Wadham College, Oxford, where he was awarded a first class honours degree in mathematics. In 1991 he completed a doctorate in mathematics on discrete groups, analytic groups and Poincaré series, supervised by Dan Segal.
Career and research
Du Sautoy's research "uses classical tools from number theory to explore the mathematics of symmetry". Du Sautoy's academic work concerns mainly group theory
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https://en.wikipedia.org/wiki/Canonical%20quantum%20gravity
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In physics, canonical quantum gravity is an attempt to quantize the canonical formulation of general relativity (or canonical gravity). It is a Hamiltonian formulation of Einstein's general theory of relativity. The basic theory was outlined by Bryce DeWitt in a seminal 1967 paper, and based on earlier work by Peter G. Bergmann using the so-called canonical quantization techniques for constrained Hamiltonian systems invented by Paul Dirac. Dirac's approach allows the quantization of systems that include gauge symmetries using Hamiltonian techniques in a fixed gauge choice. Newer approaches based in part on the work of DeWitt and Dirac include the Hartle–Hawking state, Regge calculus, the Wheeler–DeWitt equation and loop quantum gravity.
Canonical quantization
In the Hamiltonian formulation of ordinary classical mechanics the Poisson bracket is an important concept. A "canonical coordinate system" consists of canonical position and momentum variables that satisfy canonical Poisson-bracket relations,
where the Poisson bracket is given by
for arbitrary phase space functions and . With the use of Poisson brackets, the Hamilton's equations can be rewritten as,
These equations describe a "flow" or orbit in phase space generated by the Hamiltonian . Given any phase space function , we have
In canonical quantization the phase space variables are promoted to quantum operators on a Hilbert space and the Poisson bracket between phase space variables is replaced by the canonical
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https://en.wikipedia.org/wiki/Sudan%20Red%207B
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Sudan Red 7B, also known as Solvent Red 19, Ceres Red 7B, Fat Red 7B, Hexatype carmine B, Lacquer red V3B, Oil violet, Organol bordeaux B, Sudanrot 7B, Typogen carmine, and C.I. 26050, is a red diazo dye. Chemically it is N-ethyl-1-[[p-(phenylazo)phenyl]azo]-2-naphthalenamine. It is soluble in oils and insoluble in water.
It is used in biology for staining, and in industry as one of the fuel dyes. It can be also present in red laser toners.
References
Azo dyes
Staining dyes
Sudan dyes
Fuel dyes
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https://en.wikipedia.org/wiki/Pinacol%20rearrangement
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The pinacol–pinacolone rearrangement is a method for converting a 1,2-diol to a carbonyl compound in organic chemistry. The 1,2-rearrangement takes place under acidic conditions. The name of the rearrangement reaction comes from the rearrangement of pinacol to pinacolone.
This reaction was first described by Wilhelm Rudolph Fittig in 1860 of the famed Fittig reaction involving coupling of 2 aryl halides in presence of sodium metal in dry ethereal solution.
Mechanism
In the course of this organic reaction, protonation of one of the –OH groups occurs and a carbocation is formed. If the –OH groups are not alike (i.e. the pinacol is asymmetrical), then the one which creates a more stable carbocation participates in the reaction. Subsequently, an alkyl group from the adjacent carbon migrates to the carbocation center.
The driving force for this rearrangement step is believed to be the relative stability of the resultant oxonium ion. Although the initial carbocation is already tertiary, the oxygen can stabilize the positive charge much more favorably due to the complete octet configuration at all centers. It can also be seen as the -OH's lone pairs pushing an alkyl group off as seen in the asymmetrical pinacol example. The migration of alkyl groups in this reaction occurs in accordance with their usual migratory aptitude, i.e.phenyl carbocation > hydride > tertiary carbocation (if formed by migration) > secondary carbocation (if formed by migration) > methyl carbocation. {Why ca
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https://en.wikipedia.org/wiki/Serine%20octamer%20cluster
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The Serine octamer cluster in physical chemistry is an unusually stable cluster consisting of eight serine molecules (Ser) implicated in the origin of homochirality. This cluster was first discovered in mass spectrometry experiments. Electrospray ionization of an aerosol of serine in methanol results in a mass spectrum with a prominent ion peak of 841 corresponding to the Ser8+H+ cation. The smaller and larger clusters are virtually absent in the spectrum and therefore the number 8 is called a magic number. The same octamer ions are also produced by rapid evaporation of a serine solution on a hot (200-250 °C) metal surface or by sublimation of solid serine. After production, detection again is by mass-spectroscopic means. For the discussion of homochirality, these laboratory production methods are designed to mimic prebiotic conditions.
The cluster is not only unusually stable but also unusual because the clusters have a strong homochiral preference. A racemic serine solution produces a minimum amount of cluster and with solutions of both enantiomers a maximum amount is formed of both homochiral D-Ser8 and L-Ser8. In another experiment cluster formation of a racemic mixture with deuterium enriched L-serine results in a product distribution with hardly any 50/50 D/L clusters but a preference for either D or L enantioenriched clusters.
A model for chiral amplification is proposed whereby enantioenriched clusters are formed from a non-racemic mixture already enriched by L-ser
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https://en.wikipedia.org/wiki/Alcohol
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Alcohol most commonly refers to:
Alcohol (chemistry), an organic compound in which a hydroxyl group is bound to a carbon atom
Alcohol (drug), an intoxicant found in alcoholic drinks
Alcohol may also refer to:
Chemicals
Ethanol, one of several alcohols, commonly known as alcohol in everyday life
Alcoholic beverage, sometimes referred to as "alcohol", any drink containing ethanol
Surrogate alcohol, any substance containing ethanol that is intentionally consumed by humans but is not meant for human consumption
Methanol, a commodity chemical that can serve as a precursor to other chemicals
Alcohol fuel, a fuel containing alcohols
Alcohol powder, a powdered form of alcohol
Fusel alcohol, a mixture of several alcohols (chiefly amyl alcohol) produced as a by-product of alcoholic fermentation.
Alcohols (medicine), the use of alcohols in medicine
Rubbing alcohol, a solution of denatured or isopropyl alcohol used in medicine
Music
"Alcohol" (Barenaked Ladies song), a song by Barenaked Ladies from their album Stunt
"Alcohol" (Brad Paisley song), a song by Brad Paisley from his album Time Well Wasted
"Alcohol" (CSS song), a song by CSS from their album Cansei de Ser Sexy
"Alcohol", a song by the Butthole Surfers from the album Independent Worm Saloon
"Alcohol", a song by Gang Green from the album Another Wasted Night
"Alcohol", a song by Gogol Bordello from the album Super Taranta!
"Alcohol", a song by the Kinks on their albums Muswell Hillbillies and Everybody's in
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https://en.wikipedia.org/wiki/MDL%20Chime
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MDL Chime was a free plugin used by web browsers to display the three-dimensional structures of molecules. and was based on the RasMol code.
Chime was used by a wide range of biochemistry web sites for the visualization of macromolecules, many of which were linked to the World Index of Molecular Visualization Resources MolVisIndex.Org. Chime was also used until 2006 at the Protein Data Bank to examine structures stored there.
Although available in 1996 in both Windows 95 and classic Mac OS versions for both Netscape and Internet Explorer browsers, development of Chime did not follow the move to Mac OS X for the Mac and support for Windows-based browsers other than Internet Explorer was limited (although it works well in Mozilla Firefox). One significant feature added in 1997 was the ability to display spectroscopic data in the form of the IUPAC JCAMP-DX protocols. Apart from this, most subsequent updates were for the installation package to follow the development of Windows and Internet Explorer. Accelrys announced in 2012 that Chime was no longer supported and would remain available for download until the end of 2012. Chime was part of the ISIS product line acquired by Symyx Technologies from scientific publisher Elsevier in October 2007. Now Chime is owned by Dassault Systemes BIOVIA (formerly Accelrys), and has been merged into Discovery Studio, but no longer exists as a free browser plugin.
Chime largely has been superseded by Jmol, a non-proprietary open-source Java
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https://en.wikipedia.org/wiki/Converse%20relation
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In mathematics, the converse relation, or transpose, of a binary relation is the relation that occurs when the order of the elements is switched in the relation. For example, the converse of the relation 'child of' is the relation 'parent of'. In formal terms, if and are sets and is a relation from to then is the relation defined so that if and only if In set-builder notation,
The notation is analogous with that for an inverse function. Although many functions do not have an inverse, every relation does have a unique converse. The unary operation that maps a relation to the converse relation is an involution, so it induces the structure of a semigroup with involution on the binary relations on a set, or, more generally, induces a dagger category on the category of relations as detailed below. As a unary operation, taking the converse (sometimes called conversion or transposition) commutes with the order-related operations of the calculus of relations, that is it commutes with union, intersection, and complement.
Since a relation may be represented by a logical matrix, and the logical matrix of the converse relation is the transpose of the original, the converse relation is also called the transpose relation. It has also been called the opposite or dual of the original relation, or the inverse of the original relation, or the reciprocal of the relation
Other notations for the converse relation include or
Examples
For the usual (maybe strict or partial) order re
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https://en.wikipedia.org/wiki/Fishtail
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Fishtail may refer to:
Biology
The rearmost fish fin or caudal fin
Fishtail palm (genus Caryota)
Transportation
Fishtailing, a problem in car handling
Fishtail Air, a helicopter airline based in Kathmandu, Nepal
Places
Fishtail, Montana, a town
Fishtail Point, southernmost point of Shults Peninsula in Antarctica
Fishtail Lake, lake on Vancouver Island in British Columbia, Canada
Fishtail Rock, a geologic feature on Hoi Sham Island, a former island near Hong Kong
Fishtail Butte; see List of mountains in Stillwater County, Montana
Fishtail Lagoon, a body of water in the Keyhaven, Pennington, Oxey and Normandy Marshes
Machapuchare, "Fish's Tail", a mountain in Nepal
Tools
Fishtail (tool), a wood carving tool and for gardening
Fishtail gauge
Fishtail projectile point
Clothing
Fishtail parka, a type of anorak such as the US Army's M-65 parka
Fishtail skirt
Fishtail back trousers, a high back design for trousers that is designed for use with Suspenders (American English, Canadian English) or braces (British English).
Fishtail wrap, a style of folding or draping a sari
Fishtail train, a flared train
Culture
Fishtail (Quickstep), a Quickstep dance figure
A form of the scrollwork, graphic design
See also
Fish tale (disambiguation)
Lobster Trap and Fish Tail, mobile by American artist Alexander Calder
Fish Tail Blues, a blues song attributed to American musician Jelly Roll Morton
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https://en.wikipedia.org/wiki/Delay%20differential%20equation
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In mathematics, delay differential equations (DDEs) are a type of differential equation in which the derivative of the unknown function at a certain time is given in terms of the values of the function at previous times.
DDEs are also called time-delay systems, systems with aftereffect or dead-time, hereditary systems, equations with deviating argument, or differential-difference equations. They belong to the class of systems with the functional state, i.e. partial differential equations (PDEs) which are infinite dimensional, as opposed to ordinary differential equations (ODEs) having a finite dimensional state vector. Four points may give a possible explanation of the popularity of DDEs:
Aftereffect is an applied problem: it is well known that, together with the increasing expectations of dynamic performances, engineers need their models to behave more like the real process. Many processes include aftereffect phenomena in their inner dynamics. In addition, actuators, sensors, and communication networks that are now involved in feedback control loops introduce such delays. Finally, besides actual delays, time lags are frequently used to simplify very high order models. Then, the interest for DDEs keeps on growing in all scientific areas and, especially, in control engineering.
Delay systems are still resistant to many classical controllers: one could think that the simplest approach would consist in replacing them by some finite-dimensional approximations. Unfortunately,
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https://en.wikipedia.org/wiki/OSR
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OSR may refer to:
Science and technology
Operational sex ratio, of reproductively available males to females
On-stack replacement, used by Jikes RVM, a Java virtual machine
Optical solar reflector, a radiator material for space craft
OEM Service Release, a Windows 95 distribution
Open-source robotics
Transportation
Leoš Janáček Airport Ostrava, in Czech Republic, IATA code OSR
Oil Spill Response, United Kingdom aircraft operator
Ontario Southland Railway, in Canada
Texas State Highway OSR, in the US
Other uses
Old School Renaissance, a movement within tabletop role-playing games
Owasippe Scout Reservation, a Boy Scout camp in Twin Lake, Michigan, U.S.
Orchestre de la Suisse Romande, a Swiss symphony orchestra
Operational Situation Reports, or Einsatzgruppen reports, dispatches of the Nazi death squads
Ohio State Reformatory, a historic US prison
Odessa Soviet Republic, a short-lived Soviet republic
Office of Strategic Research, a CIA intelligence analysis organization once headed by Richard Lehman
Oilseed rape, a widely cultivated grain crop
Overseas Service Ribbon, a US military award
See also
OSR1, a gene
OSR2 (gene)
BDTH2 or OSR#1, an organosulfur compound used as a chelation agent
OSRIC, or Old School Reference and Index Compilation, a Dungeons & Dragons retro-clone
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https://en.wikipedia.org/wiki/Marek%20Kohn
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Marek Kohn is a British science writer on evolution, biology and society.
Early life and education
Kohn holds an undergraduate degree in neurobiology from the University of Sussex, a PhD from the University of Brighton and has held fellowships at both schools. He is currently an honorary research fellow with the latter. His articles have appeared in The Independent, New Scientist, Prospect, Financial Times, and The Guardian, and he writes frequently for the New Statesman.
Career
His first two books were on drugs, their cultural history, and their politics. He is the author of seven books and hundreds of articles.
Kohn's book, A Reason for Everything (2004), has received widespread praise, including Steve Jones' stating in his Nature review that "every evolutionist should read it," and Andrew Brown, author of the Darwin Wars, writing in his Guardian review, "one of the best science writers we have."
In 1999, Kohn had proposed, together with the archaeologist Steven Mithen, the "sexy hand-axe hypothesis." This hypothesis proposes that pressures related to sexual selection could result in men making symmetric hand axes to demonstrate their cognitive and physiological fitness.
Following the publication of his name in a list of persons invited to participate in Steve Sailer's Human Biodiversity Institute discussion pages, Kohn wrote to Lynn Conway to dissociate himself from many of the participants' scientific and political views.
Kohn has also written about the possible
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https://en.wikipedia.org/wiki/Method%20of%20averaging
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In mathematics, more specifically in dynamical systems, the method of averaging (also called averaging theory) exploits systems containing time-scales separation: a fast oscillation versus a slow drift. It suggests that we perform an averaging over a given amount of time in order to iron out the fast oscillations and observe the qualitative behavior from the resulting dynamics. The approximated solution holds under finite time inversely proportional to the parameter denoting the slow time scale. It turns out to be a customary problem where there exists the trade off between how good is the approximated solution balanced by how much time it holds to be close to the original solution.
More precisely, the system has the following form
of a phase space variable The fast oscillation is given by versus a slow drift of . The averaging method yields an autonomous dynamical system
which approximates the solution curves of inside a connected and compact region of the phase space and over time of .
Under the validity of this averaging technique, the asymptotic behavior of the original system is captured by the dynamical equation for . In this way, qualitative methods for autonomous dynamical systems may be employed to analyze the equilibria and more complex structures, such as slow manifold and invariant manifolds, as well as their stability in the phase space of the averaged system.
In addition, in a physical application it might be reasonable or natural to replace a mathematica
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https://en.wikipedia.org/wiki/Fritz-Albert%20Popp
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Fritz-Albert Popp (11 May 1938 – 4 August 2018) was a German researcher in biophysics, particularly in the study of biophotons.
Biography
Popp was born in 1938 in Frankfurt. He has a diploma in Experimental Physics (1966, University Würzburg), a Ph.D. in Theoretical Physics (1969, University Mainz), and a habilitation in Biophysics and Medicine (1973, University Marburg). He was awarded Professorship (H2) by the Senate of Marburg University, and lectured at Marburg University from 1973 to 1980.
In the mid-1970s, Popp rediscovered and made the first extensive physical analysis of biophotons (they were originally discovered in 1922).
He was head of a research group in the pharmaceutical industry in Worms from 1981 to 1983 and head of a research group at the Institute of Cell Biology (University of Kaiserslautern) from 1983 to 1986 and of another research group at the Technology Center in Kaiserslautern. Popp became an Invited Member and of the New York Academy of Sciences and an Invited Foreign Member of the Russian Academy of Natural Sciences (RANS).
Popp is the founder of the International Institute of Biophysics in Neuss (1996), Germany, an international network of 19 research groups from 13 countries involved in biophoton research and coherence systems in biology.
Google Scholar, h-index 43 ()
Scopus, h index 22 ()
References
1938 births
2018 deaths
German biophysicists
Scientists from Frankfurt
People from Hesse-Nassau
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https://en.wikipedia.org/wiki/Seetakt
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Seetakt was a shipborne radar developed in the 1930s and used by the German Navy (Kriegsmarine) during World War II.
Development
In Germany during the late 1920s, Hans Hollmann began working in the field of microwaves, which were to later become the basis of almost all radar systems. In 1935 he published Physics and Technique of Ultrashort Waves, which was picked up by researchers around the world. At the time he had been most interested in their use for communications, but he and his partner Hans-Karl von Willisen had also worked on radar-like systems.
In 1928 Hollmann, von Willisen and Paul-Günther Erbslöh started a company Gesellschaft für elektroakustische und mechanische Apparate (GEMA). In the autumn of 1934, GEMA built the first commercial radar system for detecting ships, similar to a system developed by Christian Hülsmeyer. Operating in the 50 cm range it could detect ships up to 10 km away. This early version of the system only provided a warning that a ship was in the general vicinity of the direction the antenna was pointed, it did not provide accurate direction or any sort of range information. The purpose was to provide an anti-collision system at night, in fog, and other times of limited visibility.
By order of the German navy, in the summer of 1935 they developed a pulse radar with which they could spot the cruiser Königsberg at a distance of 8 km, with an accuracy of up to 50 m, enough for gun-laying. The same system could also detect an aircraft at 500 m
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https://en.wikipedia.org/wiki/Maximal%20munch
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In computer programming and computer science, "maximal munch" or "longest match" is the principle that when creating some construct, as much of the available input as possible should be consumed.
The earliest known use of this term is by R.G.G. Cattell in his PhD thesis on automatic derivation of code generators for compilers.
Application
For instance, the lexical syntax of many programming languages requires that tokens be built from the maximum possible number of characters from the input stream. This is done to resolve the problem of inherent ambiguity in commonly used regular expressions such as [a-z]+ (one or more lower-case letters).
The term is also used in compilers in the instruction selection stage to describe a method of "tiling" — determining how a structured tree representing a program in an intermediate language should be converted into linear machine code. An entire subtree might be converted into just one machine instruction, and the problem is how to split the tree into non-overlapping "tiles", each representing one machine instruction. An effective strategy is simply to make a tile of the largest subtree possible at any given point, which is called "maximal munch".
Drawbacks
In some situations, "maximal munch" leads to undesirable or unintuitive outcomes. For instance, in the C programming language, the statement x=y/*z; (without any whitespace) will probably lead to a syntax error, since the /* character sequence initiates a (unintended) comment that
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https://en.wikipedia.org/wiki/Nonnegative%20matrix
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In mathematics, a nonnegative matrix, written
is a matrix in which all the elements are equal to or greater than zero, that is,
A positive matrix is a matrix in which all the elements are strictly greater than zero. The set of positive matrices is a subset of all non-negative matrices. While such matrices are commonly found, the term is only occasionally used due to the possible confusion with positive-definite matrices, which are different. A matrix which is both non-negative and is positive semidefinite is called a doubly non-negative matrix.
A rectangular non-negative matrix can be approximated by a decomposition with two other non-negative matrices via non-negative matrix factorization.
Eigenvalues and eigenvectors of square positive matrices are described by the Perron–Frobenius theorem.
Properties
The trace and every row and column sum/product of a nonnegative matrix is nonnegative.
Inversion
The inverse of any non-singular M-matrix is a non-negative matrix. If the non-singular M-matrix is also symmetric then it is called a Stieltjes matrix.
The inverse of a non-negative matrix is usually not non-negative. The exception is the non-negative monomial matrices: a non-negative matrix has non-negative inverse if and only if it is a (non-negative) monomial matrix. Note that thus the inverse of a positive matrix is not positive or even non-negative, as positive matrices are not monomial, for dimension .
Specializations
There are a number of groups of matrices tha
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https://en.wikipedia.org/wiki/Fundamental%20vector%20field
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In the study of mathematics and especially differential geometry, fundamental vector fields are an instrument that describes the infinitesimal behaviour of a smooth Lie group action on a smooth manifold. Such vector fields find important applications in the study of Lie theory, symplectic geometry, and the study of Hamiltonian group actions.
Motivation
Important to applications in mathematics and physics is the notion of a flow on a manifold. In particular, if is a smooth manifold and is a smooth vector field, one is interested in finding integral curves to . More precisely, given one is interested in curves such that:
for which local solutions are guaranteed by the Existence and Uniqueness Theorem of Ordinary Differential Equations. If is furthermore a complete vector field, then the flow of , defined as the collection of all integral curves for , is a diffeomorphism of . The flow given by is in fact an action of the additive Lie group on .
Conversely, every smooth action defines a complete vector field via the equation:
It is then a simple result that there is a bijective correspondence between actions on and complete vector fields on .
In the language of flow theory, the vector field is called the infinitesimal generator. Intuitively, the behaviour of the flow at each point corresponds to the "direction" indicated by the vector field. It is a natural question to ask whether one may establish a similar correspondence between vector fields and more arbitr
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https://en.wikipedia.org/wiki/Swift%20Engineering
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Swift Engineering is an American spacecraft engineering firm that builds autonomous systems, helicopters, submarines, spacecraft, ground vehicles, robotics, and composite parts. Swift used to produce racing cars for open-wheel racing series, including Formula Ford, Formula Atlantic, the Champ Car World Series and Formula Nippon, having designed and fabricated over 500 race cars.
History
Swift Engineering was founded in 1983 by David Bruns, Alex Cross, R. K. Smith, and Paul White under the name Swift Racing Cars. Their first car, the DB-1, was a Formula Ford which won the SCCA National Championship in its debut race. The company later built cars for Sports 2000, Formula Ford 2000, Formula Atlantic, and CART. Swift chassis won the Atlantic Championship from 1989 to 1992 and British Formula Renault in 1990.
In 1991, Swift was purchased by Panasonic executive and former Indycar racing driver Hiro Matsushita, grandson of Panasonic founder Konosuke Matsushita, who renamed the firm Swift Engineering. Under his direction, Swift moved up to the CART World Series for 1997, with two cars entered by Newman/Haas Racing and driven by Michael Andretti and Christian Fittipaldi. In CART, Swifts got four wins and 24 podiums from 182 race entries. Tarso Marques was the last driver to race a Swift chassis in CART in the 2000 season.
In 2000, Swift Engineering started to provide vertically integrated, multi-disciplined product development services including design, development, engineering, te
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https://en.wikipedia.org/wiki/Edward%20Bouchet
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Edward Alexander Bouchet (September 15, 1852 – October 28, 1918) was an American physicist and educator and was the first African American to earn a Ph.D. from any American university, completing his dissertation in physics at Yale University in 1876. On the basis of his academic record he was elected to the Phi Beta Kappa Society. In 1874, he became one of the first African Americans to graduate from Yale College.
Although Bouchet was elected to Phi Beta Kappa along with other members of the Yale class of 1874, the official induction did not take place until 1884, when the Yale chapter was reorganized after thirteen years of inactivity. Because of the circumstances, Bouchet was not the first African American elected to Phi Beta Kappa, as many historical accounts state; that honor belongs to George Washington Henderson (University of Vermont). Bouchet was also among the first 20 Americans (of any race) to receive a Ph.D. in physics and was the sixth to earn a Ph.D. in physics from Yale.
Early life
Edward Bouchet was born at home in New Haven, Connecticut to parents William Francis Bouchet and Susan (Cooley) Bouchet in 1852. His father had been brought to New Haven from Charleston, South Carolina in 1824 as the enslaved valet of a young plantation owner and Yale student. William Francis was emancipated by his owner when the latter graduated from Yale, and he then went to work as a janitor and later porter at Yale, and served as a deacon of the Temple Street Church, the oldes
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https://en.wikipedia.org/wiki/Nobel%20Committee
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A Nobel Committee is a working body responsible for most of the work involved in selecting Nobel Prize laureates. There are five Nobel Committees, one for each Nobel Prize.
Four of these committees (for prizes in physics, chemistry, physiology or medicine, and literature) are working bodies within their prize awarding institutions, the Royal Swedish Academy of Sciences, the Karolinska Institute, and the Swedish Academy. These four Nobel Committees only propose laureates, while the final decision is taken in a larger assembly. This assembly is composed of the entire academies for the prizes in physics, chemistry, and literature, as well as the 50 members of the Nobel Assembly at the Karolinska Institute for the prize in physiology or medicine.
The fifth Nobel Committee is the Norwegian Nobel Committee, responsible for the Nobel Peace Prize. This committee has a different status since it is both the working body and the deciding body for its prize.
See also
Nobel Committee in Literature
Nobel Committee for Physics
Nobel Committee for Chemistry
Nobel Committee for Physiology or Medicine
Norwegian Nobel Committee
Nobel Prize controversies
Matilda effect
References
Nobel Prize
Scientific organizations based in Sweden
Awards juries and committees
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https://en.wikipedia.org/wiki/Polar%20space
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In mathematics, in the field of geometry, a polar space of rank n (), or projective index , consists of a set P, conventionally called the set of points, together with certain subsets of P, called subspaces, that satisfy these axioms:
Every subspace is isomorphic to a projective space with and K a division ring. (That is, it is a Desarguesian projective geometry.) For each subspace the corresponding d is called its dimension.
The intersection of two subspaces is always a subspace.
For each subspace A of dimension and each point p not in A, there is a unique subspace B of dimension containing p and such that is -dimensional. The points in are exactly the points of A that are in a common subspace of dimension 1 with p.
There are at least two disjoint subspaces of dimension .
It is possible to define and study a slightly bigger class of objects using only relationship between points and lines: a polar space is a partial linear space (P,L), so that for each point p ∈ P and
each line l ∈ L, the set of points of l collinear to p, is either a singleton or the whole l.
Finite polar spaces (where P is a finite set) are also studied as combinatorial objects.
Generalized quadrangles
A polar space of rank two is a generalized quadrangle; in this case, in the latter definition, the set of points of a line collinear with a point p is the whole of only if p ∈ . One recovers the former definition from the latter under the assumptions that lines have more than 2 points, p
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https://en.wikipedia.org/wiki/Trifluoroiodomethane
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Trifluoroiodomethane, also referred to as trifluoromethyl iodide is a halomethane with the formula CF3I. It is an experimental alternative to Halon 1301 (CBrF3) in unoccupied areas. It would be used as a gaseous fire suppression flooding agent for in-flight aircraft and electronic equipment fires.
Chemistry
It is used in the rhodium-catalyzed α-trifluoromethylation of α,β-unsaturated ketones.
It can be used as a new generation fire extinguishing agent to replace Halon in fire protection systems. The mechanism of extinguishing fires for CF3I is active and primarily based on interruption of the chain reaction in the combustion area of the flame by so-called "negative" catalytic action. It is also used as an eco-friendly insulation gas to replace SF6 in electrical power industry.
In the presence of sunlight or at temperatures above 100 °C it can react with water, forming hazardous by-products such as hydrogen fluoride (HF), hydrogen iodide (HI) and carbonyl fluoride (COF2).
Environmental effects
Trifluoroiodomethane contains carbon, fluorine, and iodine atoms. Although iodine is several hundred times more efficient at destroying stratospheric ozone than chlorine, experiments have shown that because the weak C-I bond breaks easily under the influence of water (owing to the electron-attracting fluorine atoms), trifluoroiodomethane has an ozone depleting potential less than one-thousandth that of Halon 1301 (0.008-0.01). Its atmospheric lifetime, at less than 1 month, is less
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https://en.wikipedia.org/wiki/Center%20manifold
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In the mathematics of evolving systems, the concept of a center manifold was originally developed to determine stability of degenerate equilibria. Subsequently, the concept of center manifolds was realised to be fundamental to mathematical modelling.
Center manifolds play an important role in bifurcation theory because interesting behavior takes place on the center manifold and in multiscale mathematics because the long time dynamics of the micro-scale often are attracted to a relatively simple center manifold involving the coarse scale variables.
Informal description
Saturn's rings capture much center-manifold geometry. Dust particles in the rings are subject to tidal forces, which act characteristically to "compress and stretch". The forces compress particle orbits into the rings, stretch particles along the rings, and ignore small shifts in ring radius. The compressing direction defines the stable manifold, the stretching direction defining the unstable manifold, and the neutral direction is the center manifold.
While geometrically accurate, one major difference distinguishes Saturn's rings from a physical center manifold. Like most dynamical systems, particles in the rings are governed by second-order laws. Understanding trajectories requires modeling position and a velocity/momentum variable, to give a tangent manifold structure called phase space. Physically speaking, the stable, unstable and neutral manifolds of Saturn's ring system do not divide up the coo
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https://en.wikipedia.org/wiki/Trait
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Trait may refer to:
Phenotypic trait in biology, which involve genes and characteristics of organisms
Genotypic trait, sometimes but not always presenting as a phenotypic trait
Personality, traits that predict an individual's behavior.
Trait theory in psychology
Trait (computer programming), a model for structuring object-oriented programs (a template class in the C++ programming language)
Entertainment
Trait (album), the first and only EP by the industrial rock/metal band Pailhead
Traits (Joe Morris album)
Trait (role-playing games), a type of role-playing statistic
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