source
stringlengths 31
207
| text
stringlengths 12
1.5k
|
|---|---|
https://en.wikipedia.org/wiki/Kirby%E2%80%93Siebenmann%20class
|
In mathematics, more specifically in geometric topology, the Kirby–Siebenmann class is an obstruction for topological manifolds to allow a PL-structure.
The KS-class
For a topological manifold M, the Kirby–Siebenmann class is an element of the fourth cohomology group of M that vanishes if M admits a piecewise linear structure.
It is the only such obstruction, which can be phrased as the weak equivalence of TOP/PL with an Eilenberg–MacLane space.
The Kirby-Siebenmann class can be used to prove the existence of topological manifolds that do not admit a PL-structure. Concrete examples of such manifolds are , where stands for Freedman's E8 manifold.
The class is named after Robion Kirby and Larry Siebenmann, who developed the theory of topological and PL-manifolds.
See also
Hauptvermutung
References
Homology theory
Geometric topology
Structures on manifolds
Surgery theory
|
https://en.wikipedia.org/wiki/Exotic%20R4
|
{{DISPLAYTITLE:Exotic R4}}
In mathematics, an exotic is a differentiable manifold that is homeomorphic (i.e. shape preserving) but not diffeomorphic (i.e. non smooth) to the Euclidean space The first examples were found in 1982 by Michael Freedman and others, by using the contrast between Freedman's theorems about topological 4-manifolds, and Simon Donaldson's theorems about smooth 4-manifolds. There is a continuum of non-diffeomorphic differentiable structures of as was shown first by Clifford Taubes.
Prior to this construction, non-diffeomorphic smooth structures on spheresexotic sphereswere already known to exist, although the question of the existence of such structures for the particular case of the 4-sphere remained open (and still remains open as of 2023). For any positive integer n other than 4, there are no exotic smooth structures on in other words, if n ≠ 4 then any smooth manifold homeomorphic to is diffeomorphic to
Small exotic R4s
An exotic is called small if it can be smoothly embedded as an open subset of the standard
Small exotic can be constructed by starting with a non-trivial smooth 5-dimensional h-cobordism (which exists by Donaldson's proof that the h-cobordism theorem fails in this dimension) and using Freedman's theorem that the topological h-cobordism theorem holds in this dimension.
Large exotic R4s
An exotic is called large if it cannot be smoothly embedded as an open subset of the standard
Examples of large exotic can be constructed
|
https://en.wikipedia.org/wiki/Donaldson%27s%20theorem
|
In mathematics, and especially differential topology and gauge theory, Donaldson's theorem states that a definite intersection form of a compact, oriented, smooth manifold of dimension 4 is diagonalisable. If the intersection form is positive (negative) definite, it can be diagonalized to the identity matrix (negative identity matrix) over the . The original version of the theorem required the manifold to be simply connected, but it was later improved to apply to 4-manifolds with any fundamental group.
History
The theorem was proved by Simon Donaldson. This was a contribution cited for his Fields medal in 1986.
Idea of proof
Donaldson's proof utilizes the moduli space of solutions to the anti-self-duality equations on a principal -bundle over the four-manifold . By the Atiyah–Singer index theorem, the dimension of the moduli space is given by
where , is the first Betti number of and is the dimension of the positive-definite subspace of with respect to the intersection form. When is simply-connected with definite intersection form, possibly after changing orientation, one always has and . Thus taking any principal -bundle with , one obtains a moduli space of dimension five.
This moduli space is non-compact and generically smooth, with singularities occurring only at the points corresponding to reducible connections, of which there are exactly many. Results of Clifford Taubes and Karen Uhlenbeck show that whilst is non-compact, its structure at infinity can be r
|
https://en.wikipedia.org/wiki/Daniel%20Simberloff
|
Daniel Simberloff is an American biologist and ecologist. He earned his Ph.D. from Harvard University in 1969. He is currently Gore Hunger Professor of Environmental Science at the University of Tennessee, editor-in-chief of the journal Biological Invasions, and a member of the National Academy of Sciences.
Early life and education
Simberloff received his Bachelor of Arts from Harvard College in 1964, and his Ph.D. in biology from Harvard University in 1969. He wanted to go to graduate school for mathematics, but changed his mind after taking a major biology course from future Nobel Prize winner, George Wald.
Career
Simberloff was a faculty member at Florida State University from 1968-1997 before relocating to the University of Tennessee, Knoxville. He is currently a distinguished professor there in the Department of Ecology and Evolutionary Biology. His more recent work focuses on the presence of invasive species, and raises the “specter of ‘invasional meltdown”. At present, Simberloff has a long-term project in Patagonia on the invasion of conifer trees, involving introduced deer, boar, and fungi. Simberloff has a total of over 350 publications, and he is currently working on several papers on invasive biology.
Academic Work
Simberloff's doctoral dissertation tested the theory of island biogeography proposed by Robert H. MacArthur and Edward O. Wilson, resulting in a paper that won the Ecological Society of America's Mercer Award in 1971 and was included as one of fo
|
https://en.wikipedia.org/wiki/Johan%20August%20Wahlberg
|
Johan August Wahlberg (9 October 1810, in Lackarebäck, Sweden – 6 March 1856, in Lake Ngami, Bechuanaland) was a Swedish naturalist and explorer.
Wahlberg started studying chemistry at the University of Uppsala in 1829, and later forestry, agronomy and natural science, graduating from the Swedish Forestry Institute in 1834. In 1832 he joined Professor Carl Henrik Boheman, a famous entomologist, on a collecting trip to Norway. In 1833 and 1834 he travelled in Sweden and Germany on forestry research projects. He joined the Office of Land Survey and was appointed an engineer in 1836, becoming an instructor at the Swedish Land Survey College.
He travelled in southern Africa between 1838 and 1856, sending thousands of natural history specimens back to Sweden. He was exploring the Okavango area when he was killed, along the Thamalakane river about 10 km northwest of Maun in today's Botswana, by a wounded elephant.
Before his death was known in Sweden, on October 8, 1856 he was elected a member of the Royal Swedish Academy of Sciences, since the news of his death had not reached Stockholm at this time. He is thus the only member of this academy who has been elected after his death.
Legacy
Wahlberg is commemorated in Wahlberg's eagle Aquila wahlbergi (Sundevall 1851), Wahlberg's honeyguide Prodotiscus regulus (Sundevall 1850), Wahlberg's cormorant Phalacrocorax neglectus, Wahlberg's epauletted fruit bat Epomophorus wahlbergi, the bush squeaker Arthroleptis wahlbergii Smith, 1849
|
https://en.wikipedia.org/wiki/Franz%20Ludwig%20von%20Cancrin
|
Franz Ludwig von Cancrin (February 21, 1738 in Breidenbach – 1812) was a German mineralogist, metallurgist, architect and writer.
He was born into a German mining family where he was trained by his father in the science of mining. In 1764, he entered the service of the landgrave of Hesse-Kassel at Hanau, becoming professor of mathematics at the military academy, head of the civil engineering department of the state, director of the theatre and (1774) of the mint. A work on the copper mines of Elesse (1767) earned him a European reputation, and in 1783 he accepted from Catherine II of Russia the directorship of the famous Staraya salt-works, living thenceforth in Russia.
In 1798 he became a councillor of state at St. Petersburg. He published many works on mineralogy and metallurgy, of which the most important, the Grundzüge der Berg- und Salzwerkskunde (12 vols, 1773–1791), has been translated into several languages.
His son, Count Georg von Cancrin, or Kankrin (1774–1845), was an eminent Russian minister of finance and the liaison with Alexander von Humboldt during his 1829 scientific expedition to Russia. The mineral of cancrinite is named after him.
Main works
Praktische Abhandlung von der Zubereitung der Kupfererze, Frankfurt, 1765
Beschreibung der vorzüglichsten Bergwerke in Hessen, in dem Waldekkischen, an dem Haarz, in dem Mansfeldischen, in Chursachsen, und in dem Saalfeldischen. (1767)
Erste Begriffe der unterirdischen Erdbeschreibung, Frankfurt, 1773
Gründli
|
https://en.wikipedia.org/wiki/Jacob%20T.%20Schwartz
|
Jacob Theodore "Jack" Schwartz (January 9, 1930 – March 2, 2009) was an American mathematician, computer scientist, and professor of computer science at the New York University Courant Institute of Mathematical Sciences. He was the designer of the SETL programming language and started the NYU Ultracomputer project. He founded the New York University Department of Computer Science, chairing it from 1964 to 1980.
Early life
Schwartz was born in The Bronx, New York on January 9, 1930, to Ignatz and Hedwig Schwartz. He attended Stuyvesant High School and went on to City College of New York.
Education
Schwartz received his B.S. (1949) from the City College of New York and his M.A. (1949) and Ph.D. in mathematics (1952) from Yale University. His doctoral thesis was entitled Linear Elliptic Differential Operators and his thesis advisor was Nelson Dunford.
Career
Schwartz's research interests included the theory of linear operators, von Neumann algebras, quantum field theory, time-sharing, parallel computing, programming language design and implementation, robotics, set-theoretic approaches in computational logic, proof and program verification systems; multimedia authoring tools; experimental studies of visual perception; multimedia and other high-level software techniques for analysis and visualization of bioinformatic data.
Schwartz authored 18 books and more than 100 papers and technical reports. He was also the inventor of the Artspeak programming language, which histo
|
https://en.wikipedia.org/wiki/Jonathan%20Bowen
|
Jonathan P. Bowen FBCS FRSA (born 1956) is a British computer scientist and an Emeritus Professor at London South Bank University, where he headed the Centre for Applied Formal Methods. Prof. Bowen is also the Chairman of Museophile Limited and has been a Professor of Computer Science at Birmingham City University, Visiting Professor at the Pratt Institute (New York City), University of Westminster and King's College London, and a visiting academic at University College London.
Early life and education
Bowen was born in Oxford, the son of Humphry Bowen, and was educated at the Dragon School, Bryanston School, prior to his matriculation at University College, Oxford (Oxford University) where he received the MA degree in Engineering Science.
Career
Bowen later worked at Imperial College, London, the Oxford University Computing Laboratory (now the Oxford University Department of Computer Science), the University of Reading, and London South Bank University. His early work was on formal methods in general, and later the Z notation in particular. He was Chair of the Z User Group from the early 1990s until 2011. In 2002, Bowen was elected Chair of the British Computer Society FACS Specialist Group on Formal Aspects of Computing Science. Since 2005, Bowen has been an Associate Editor-in-Chief of the journal Innovations in Systems and Software Engineering. He is also an associate editor on the editorial board for the ACM Computing Surveys journal, covering software engineering and
|
https://en.wikipedia.org/wiki/Math%20for%20America
|
Math for America (MfA) is a nonprofit organization, founded in January 2004 by American billionaire mathematician, hedge fund manager, and philanthropist Jim Simons to promote recruitment and retention of mathematics teachers in New York City secondary schools.
History
According to Simons, he founded the program to address failures in the US education system to produce students highly qualified in STEM skills and knowledge, which reduces America's ability to compete in the global economy. He perceived the cause of the failure as low quality teachers, and saw that problem in turn as being caused by low salaries, lack of prestige, and lack of support and good training making the job unattractive to qualified candidates, many of whom could get jobs in lucrative fields like quantitative finance.
Simons thus created the program to provide math and science teachers with higher salaries and better training and funded it with a $25 million pledge from his charitable foundation, the Simons Foundation. Simons pledged an additional $25 million in 2006.
In the initial program, people who were accepted into the program who had degrees in math but were not teachers received a stipend of about $18,000 per year for five years from MfA in addition to their salaries and received free tuition to a high quality one year Master's program in teaching, as well as mentoring and professional development support after the first year. The five-year period was selected because that is the period du
|
https://en.wikipedia.org/wiki/Ashton%20Lewis%20Jr.
|
Ashton Lewis Jr. (born January 22, 1972) is an American former stock car racing driver who competed in 226 races over 11 seasons. Lewis earned a degree in mechanical engineering from Old Dominion University in Norfolk, Virginia. After his racing career, he earned his MBA from the Fuqua School of Business at Duke University. As of March 2013, he is chief operating officer for First Team Automotive Group in Chesapeake, Virginia.
Busch Series career
Lewis was a driver who was especially good on road courses. He started out in the Barber Saab Pro Series for the 1992 season. After success in that series, he was offered a scholarship to race in the British Formula Ford championship.
Lewis made his Busch debut in 1993, long before he became known to most Busch fans. Driving the No. 36 Parkway Pontiac at Watkins Glen, Lewis started the race in 29th place. The team had mechanical issues partway through the race, but Lewis got back on track and finished the race in 27th place.
Lewis returned once again to the series in 1994. This time, Lewis drove the No. 80 Commerce Bank Chevy at Milwaukee Mile. Lewis was able to top his debut with a 24th-place effort despite a 38th-place start.
Lewis again made a one-off start in 1995. He had his best weekend at that point in his career, this time back at Watkins Glen. He started the race solidly in the 22nd position and stayed on the lead lap with a 13th-place finishing result.
Lewis raced in eight races in 1996 and earned a 3rd-place finish
|
https://en.wikipedia.org/wiki/Reid%20W.%20Barton
|
Reid William Barton (born May 6, 1983) is a mathematician and also one of the most successful performers in the International Science Olympiads.
Biography
Barton is the son of two environmental engineers. Barton took part-time classes at Tufts University in chemistry (5th grade), physics (6th grade), and subsequently Swedish, Finnish, French, and Chinese. Since eighth grade he worked part-time with MIT computer scientist Charles E. Leiserson on CilkChess, a computer chess program. Subsequently, he worked at Akamai Technologies with computer scientist Ramesh Sitaraman to build one of the earliest video performance measurement systems that have since become a standard in industry. After Akamai, Barton went to grad school at Harvard to pursue a Ph.D. in mathematics, which he completed in 2019 under the supervision of Michael J. Hopkins. Afterwards, he did research as a post-doctoral fellow at Pittsburgh. As of November 2021 he sits on the committee for the
Mathematical and programming competitions
Barton was the first student to win four gold medals at the International Mathematical Olympiad, culminating in full marks at the 2001 Olympiad held in Washington, D.C., shared with Gabriel Carroll, Xiao Liang and Zhang Zhiqiang.
Barton is one of seven people to have placed among the five top ranked competitors (who are themselves not ranked against each other) in the William Lowell Putnam Competition four times (2001–2004). Barton was a member of the MIT team which finished sec
|
https://en.wikipedia.org/wiki/Ornstein%E2%80%93Uhlenbeck%20process
|
In mathematics, the Ornstein–Uhlenbeck process is a stochastic process with applications in financial mathematics and the physical sciences. Its original application in physics was as a model for the velocity of a massive Brownian particle under the influence of friction. It is named after Leonard Ornstein and George Eugene Uhlenbeck.
The Ornstein–Uhlenbeck process is a stationary Gauss–Markov process, which means that it is a Gaussian process, a Markov process, and is temporally homogeneous. In fact, it is the only nontrivial process that satisfies these three conditions, up to allowing linear transformations of the space and time variables. Over time, the process tends to drift towards its mean function: such a process is called mean-reverting.
The process can be considered to be a modification of the random walk in continuous time, or Wiener process, in which the properties of the process have been changed so that there is a tendency of the walk to move back towards a central location, with a greater attraction when the process is further away from the center. The Ornstein–Uhlenbeck process can also be considered as the continuous-time analogue of the discrete-time AR(1) process.
Definition
The Ornstein–Uhlenbeck process is defined by the following stochastic differential equation:
where and are parameters and denotes the Wiener process.
An additional drift term is sometimes added:
where is a constant.
The Ornstein–Uhlenbeck process is sometimes also written
|
https://en.wikipedia.org/wiki/Josh%20Fisher
|
Joseph A "Josh" Fisher is an American and Spanish computer scientist noted for his work on VLIW architectures, compiling, and instruction-level parallelism, and for the founding of Multiflow Computer. He is a Hewlett-Packard Senior Fellow (Emeritus).
Biography
Fisher holds a BA (1968) in mathematics (with honors) from New York University and obtained a Master's and PhD degree (1979) in Computer Science from The Courant Institute of Mathematics of New York University.
Fisher joined the Yale University Department of Computer Science in 1979 as an assistant professor, and was promoted to associate professor in 1983. In 1984 Fisher left Yale to found Multiflow Computer with Yale colleagues John O'Donnell and John Ruttenberg. Fisher joined HP Labs upon the closing of Multiflow in 1990. He directed HP Labs in Cambridge, MA USA from its founding in 1994, and became an HP Fellow (2000) and then Senior Fellow (2002) upon the inception of those titles at Hewlett-Packard. Fisher retired from HP Labs in 2006.
Fisher is married (1967) to Elizabeth Fisher; they have a son, David Fisher, and a daughter, Dora Fisher. He holds Spanish citizenship due to his Sephardic heritage.
Work
Trace Scheduling
In his Ph.D. dissertation, Fisher created the Trace Scheduling compiler algorithm and coined the term Instruction-level parallelism to characterize VLIW, superscalar, dataflow and other architecture styles that involve fine-grained parallelism among simple machine-level instructions. Trace sc
|
https://en.wikipedia.org/wiki/List%20of%20Arab%20Americans
|
This is a list of Arab Americans. It includes prominent and notable Arab American individuals from various fields, such as business, science, entertainment, sports and fine arts.
Academia
Science
Elias J. Corey, Lebanese, organic chemistry professor at Harvard University, winner of the 1990 Nobel Prize in Chemistry
Ahmed Zewail, Damanhour-born Egyptian, scientist, known as the "father of femtochemistry", winner of the 1999 Nobel Prize in Chemistry
Michael E. DeBakey, Lebanese, cardiovascular surgeon and researcher, 1963 Lasker Award laureate
Omar M. Yaghi, Amman-born Jordanian, reticular chemistry pioneer; winner of the 2018 Wolf Prize in Chemistry
Mostafa El-Sayed, Egyptian, US National Medal of Science laureate; nanoscience researcher; known for the spectroscopy rule named after him, the El-Sayed rule
Riad Barmada, Aleppo-born Syrian, served as the president of the Illinois Orthopedic Society
Eman Ghoneim, Minea-born Egyptian, space scientist in desert regions
Farouk El-Baz, Zagazig-born Egyptian, space scientist who worked with NASA to assist in the planning of scientific exploration of the Moon
Huda Zoghbi, Beirut-born Lebanese, physician and medical researcher who discovered the genetic cause of the Rett syndrome
Huda Akil, Damascus-born Syrian, neuroscientist and medical researcher
Yasmine Belkaid, Algiers-born Algerian, immunologist, professor and a senior investigator at the National Institute of Allergy and Infectious Diseases
Mounir Laroussi, Sfax-born Tuni
|
https://en.wikipedia.org/wiki/Kappa%20Eta%20Kappa
|
Kappa Eta Kappa () is a co-ed professional fraternity, nationally recognized in the United States, that was founded in 1923 at the University of Iowa. KHK requires that members are majoring or will major in electrical engineering, computer engineering or computer science.
Ideals
The preamble to the constitution of KHK states the principles of the organization.
"Believing that the attainment of education as well as technical training is the aim of all true engineers, we band ourselves together to foster and promote fraternal relationships among electrical engineering students; to strive at all times for the maintenance of a complete and lasting understanding and fellowship between faculty and students; to unceasingly cherish and develop the character and ideals of service as the necessary attributes of the profession."
History
After the founding of the Alpha chapter at Iowa in 1923, other chapters were quickly added. There were five chapters that closed because of World War II. Active chapters listed in bold, inactive chapters listed in italics.
See also
Professional fraternities and sororities
References
Student organizations established in 1923
1923 establishments in Iowa
Professional fraternities and sororities in the United States
Professional Fraternity Association
|
https://en.wikipedia.org/wiki/Serre%27s%20property%20FA
|
In mathematics, Property FA is a property of groups first defined by Jean-Pierre Serre.
A group G is said to have property FA if every action of G on a tree has a global fixed point.
Serre shows that if a group has property FA, then it cannot split as an amalgamated product or HNN extension; indeed, if G is contained in an amalgamated product then it is contained in one of the factors. In particular, a finitely generated group with property FA has finite abelianization.
Property FA is equivalent for countable G to the three properties: G is not an amalgamated product; G does not have Z as a quotient group; G is finitely generated. For general groups G the third condition may be replaced by requiring that G not be the union of a strictly increasing sequence of subgroup.
Examples of groups with property FA include SL3(Z) and more generally G(Z) where G is a simply-connected simple Chevalley group of rank at least 2. The group SL2(Z) is an exception, since it is isomorphic to the amalgamated product of the cyclic groups C4 and C6 along C2.
Any quotient group of a group with property FA has property FA. If some subgroup of finite index in G has property FA then so does G, but the converse does not hold in general. If N is a normal subgroup of G and both N and G/N have property FA, then so does G.
It is a theorem of Watatani that Kazhdan's property (T) implies property FA, but not conversely. Indeed, any subgroup of finite index in a T-group has property FA.
Examples
|
https://en.wikipedia.org/wiki/Beth%20Shapiro
|
Beth Alison Shapiro (born 1976) is an American evolutionary molecular biologist. She is a professor in the Department of Ecology and Evolutionary Biology at the University of California, Santa Cruz. Shapiro's work has centered on the analysis of ancient DNA. She was awarded a MacArthur Fellowship in 2009 and a Royal Society University Research Fellowship in 2006.
Early life and education
Shapiro was born in Allentown, Pennsylvania on January 14, 1976. She grew up in Rome, Georgia, where she served as a local news presenter while attending Rome High School.
She graduated from Rome High School with a GPA of 4.0, and entered the University of Georgia in 1994. She studied Mandarin Chinese, Spanish, English literature, and geology prior to choosing ecology as her major. She graduated summa cum laude in 1999 with BA and MA degrees in ecology. The same year, she was awarded a Rhodes Scholarship followed by a Ph.D. from the University of Oxford for research on inferring evolutionary history and processes using ancient DNA supervised by Alan J. Cooper.
Career
Shapiro was appointed a Wellcome Trust Research Fellow at the University of Oxford in 2004. The same year she was appointed director of the Henry Wellcome Biomolecules Centre at Oxford, a position she held until 2007. In 2006, she was awarded a Royal Society University Research Fellowship. While at the Biomolecules Centre, Shapiro carried out mitochondrial DNA analysis of the dodo.
Shapiro's research on ecology has been publ
|
https://en.wikipedia.org/wiki/List%20of%20University%20of%20G%C3%B6ttingen%20people
|
This is a list of people who have taught or studied at the University of Göttingen:
Natural sciences and mathematics
A
Wilhelm Ackermann — Mathematics
Immo Appenzeller — Astrophysics
Cahit Arf — (Doctorate in Mathematics)
B
Heinrich Behmann — Mathematical Logic
Paul Bernays — Mathematics, mathematical logic — (Student, later Professor extraordinarius)
Patrick Blackett — Physics — Nobel Prize in Physics 1948
Johann Friedrich Blumenbach— comparative anatomy
Max Born — Mathematical Physics — (Professor ordinarius) — (1882–1970, in Göttingen 1921–1933) — Nobel Prize in Physics 1954
Walther Bothe — Physics — Nobel Prize in Physics 1954 together with Max Born
Michael Buback — Chemistry
Adolf Butenandt — Chemistry — Nobel Prize in Chemistry 1939
C
Constantin Carathéodory — Mathematics
Alonzo Church — Mathematical Logic (Postdoc)
Richard Courant — Mathematics
Haskell Curry — Mathematical Logic (Postdoc)
D
Peter Debye — Mathematical Physics — (Professor ordinarius) — (1884–1966, in Göttingen 1914–1920) — Nobel Prize in Chemistry 1936
Richard Dedekind — Mathematics
Hans Georg Dehmelt — Nobel Prize in Physics 1989
Max Delbrück — Astronomy, Physics — Nobel Prize in Medicine 1969
Paul Dirac — Physics — Nobel Prize in Physics 1933 (with Erwin Schrödinger)
Peter Gustav Lejeune Dirichlet — Mathematics
E
Manfred Eigen — Biophysical Chemistry — Nobel Prize in Chemistry 1967 (with Ronald G. W. Norrish and George Porter)
Albert Einstein — Physics — Nobel Prize in Physics 1921 — (Gues
|
https://en.wikipedia.org/wiki/John%20Ziman
|
John Michael Ziman (16 May 1925 – 2 January 2005) was a British-born New Zealand physicist and humanist who worked in the area of condensed matter physics. He was a spokesman for science, as well as a teacher and author.
Ziman was born in Cambridge, England, in 1925. His parents were Solomon Netheim Ziman and, Nellie Frances, née Gaster. The family emigrated to New Zealand when Ziman was a baby. He obtained his early education at Hamilton High School and the Victoria University College. He obtained his PhD from Balliol College, Oxford and did his early research on the theory of electrons in liquid metals at the University of Cambridge.
In 1964 he was appointed professor of theoretical physics at University of Bristol, where he wrote his Elements Of Advanced Quantum Theory (1969) which explains the rudiments of quantum field theory with an elementary condensed matter slant. During this period, his interests shifted towards the philosophy of science. He argued about the social dimension of science, and the social responsibility of scientists in numerous essays and books.
He married twice, to Rosemary Dixon in 1951 and secondly to Joan Solomon, and was survived by her and three of his four children.
See also
Nearly free electron model
Selected publications
An Introduction to Science Studies: The Philosophical and Social Aspects of Science and Technology, Cambridge: Cambridge University Press, 1987,
References
1925 births
Scientists from Cambridge
English Jews
200
|
https://en.wikipedia.org/wiki/August%20Wilhelm%20Knoch
|
August Wilhelm Knoch (June 8, 1742 – June 2, 1818) was a German naturalist born in Braunschweig. He was a professor of physics at Collegium Carolinum.
He studied theology at the University of Leipzig. In 1775 he was hired as a caretaker at the Collegium Carolinum, during which time his interests turned to natural sciences. In 1789 he became a professor of physics.
He was the author of the following works in entomology:
Beyträge zur Insektengeschichte Leipzig (Schwickert). three volumes 1781, 1782, 1783.
Neue Beyträge zur Insectenkunde Leipzig (Schwickert) 1801.
References
Biographical etymology of marine organism names. K
Parts of this article are based on a translation of the equivalent article from the German Wikipedia.
External links
Zoologica GDZ
1742 births
1818 deaths
German naturalists
German entomologists
Scientists from Braunschweig
People from Brunswick-Lüneburg
Academic staff of the Technical University of Braunschweig
|
https://en.wikipedia.org/wiki/HWP
|
HWP may refer to:
Science and technology
Half-wave plate, an optical device
Hangul (word processor), Korean software
Hardy–Weinberg principle, in population genetics
Other uses
Heavy weapons platoon
Highland Wildlife Park, in Scotland
Human Waste Project, an American band
Hutchison Whampoa Property, a property developer in Hong Kong
See also
Hoop (disambiguation)
Hwp1, fungal glycoprotein
|
https://en.wikipedia.org/wiki/Irving%20Friedman
|
Irving Friedman (January 12, 1920 – June 28, 2005) was a U.S. Geological Survey (USGS) scientist and a pioneer in geochemistry. Born in New York City, New York, he obtained a B.S. degree in chemistry from Montana State University, a M.S. degree in chemistry from Washington State University, and a Ph.D. in geochemistry at the University of Chicago.
University of Chicago
Friedman was a member of the famed group of post doctoral researchers in Nobel laureate Harold Urey’s laboratory at the Institute for Nuclear Studies at the University of Chicago. There, Friedman built the first mass spectrometer for routine measurement of the hydrogen isotope composition of water. Hydrogen has two stable isotopes and much can be deduced about the history of water from their proportions. Because of this, Friedman is called the "father of isotope hydrology."
Military
Friedman joined the Navy in 1944. His USGS bio says that he was assigned to the Naval Electronics Laboratory in Washington, D.C., but that organization was formed in 1945. His training may have spanned the difference in time, though.
USGS
In 1952, he joined the USGS in Washington, D.C., and worked for the USGS for more than 43 years. In 1962, he moved to Lakewood, Colorado, when the Isotope Geology Branch of the USGS was created. Friedman retired from the USGS in 1995, and remained active as an emeritus scientist.
Accomplishments
His scientific career was a pursuit of the understanding of every aspect of the water cycle. Thr
|
https://en.wikipedia.org/wiki/CNRC
|
CNRC may refer to:
Cajal Neuroscience Research Center
Cascadia Natural Resource Consultants
Centre National du Registre du Commerce
Children's Nutrition Research Center
Clinical Nutrition Research Center
Columbia Network Research Center
Council of National Resource Centers, a group of U.S. universities which host National Resource Centers for international studies
National Research Council of Canada (French acronym)
Commander of the United States Navy Recruiting Command
|
https://en.wikipedia.org/wiki/Love%2C%20Hell%20or%20Right
|
Love Hell or Right (Da Come Up) is an album by the hip hop producer DJ Mathematics, who is a DJ with Wu-Tang Clan.
Completely mixed, arranged and produced by Mathematics himself, Love, Hell or Right was released August 26, 2003, on his own Quewisha Records label in conjunction with High Times Records, and it went on to sell 30,000 units. It was released in CD, vinyl and cassette tape formats.
The title is a reference to the Nation of Gods and Earths's Supreme Alphabet, in which the letter "L" is seen to stand for "Love Hell or Right".
Track listing
Note: Artists marked with an asterisk (*) are not affiliated with the Wu-Tang Clan.
"Love Hell or Right (Da Intro)"
"Pimpology 101" (Buddah Bless*)
"Thank U (Da DJ's Version)" (Method Man, Ghostface Killah and Angela Neal*)
"Message to a Blackman (Skit)" (Queen-Shatiyah*)
"Juscantluv" (Eyes Low*)
"Return of Da Cobra (Skit)" (Buddah Bless*)
"Hav Mercy" (Killa Sin and La the Darkman)
"Respect Mine" (Method Man, Raekwon and Cappadonna)
"Da Heist (Skit)" (Starking*, LEO*, Karim*, and Mouth*)
"Gangsta" (Logic*, Nemy*, Mad Man* and Eyes Low*)
"Da Great Siege" (RZA)
"Message from a Blackman (Skit)"
"Real Talk (Pop's Song)" (Pop Poppa Don*)
"Hip Hop 101" (Prodigal Sunn, H-Speed*, Born Justice, Shacronz and Allah Real)
"Queens Day '88" (Pop Poppa Don* and Eyes Low*)
"Alwayz N.Y." (Masta Killa, U-God, Inspectah Deck, Buddah Bless* and Icarus Da Don*)
"Gun Talk" (Street Life and Buddah Bless*)
"...On Da Radio (Skit)" (Gh
|
https://en.wikipedia.org/wiki/Eater%20%28novel%29
|
Eater is a hard science fiction novel by American writer Gregory Benford. It was published in May 2000 by Eos. Heavy on the physics information, Eater describes humankind's encounter with a cosmic intelligence that comes in the form of a small black hole.
Plot summary
In the early 21st century, astronomers detect what appears to be a distant gamma-ray burster, a black hole engulfing another star many light years away. The data are bizarre and troubling, because only 13 hours later, a second burster appears, which, given the great distance between stars, would be impossible. Eventually, the astronomers realize that the black hole, rather than being incredibly far from us, is actually heading towards the Solar System, and moving our way at considerable speed. Stranger still, it seems to be moving under its own will; it is an intelligent being itself. This age-old cosmic being reveals that it had been born seven billion years ago and had become a wandering entity, feeding on asteroids, planets and various space debris, projecting itself forward in space through the process. Through the billions of years of its existence across the expanse of time and space, this intelligent entity has learned of many ancient civilizations in the universe. The black hole eventually sends a message to the people of Earth; it "desires converse". The black hole is willing to share the knowledge it had gained throughout the ages in return for the chance to "chat" with the humans. But eventually, som
|
https://en.wikipedia.org/wiki/Carl%20Remigius%20Fresenius
|
Carl Remigius Fresenius (28 December 1818 – 11 June 1897), was a German chemist, known for his studies in analytical chemistry.
Biography
Fresenius was born on 28 December 1818, in Frankfurt, Germany. After working for some time for a pharmacy in his native town, he entered Bonn University in 1840, and a year later migrated to Gießen, where he acted as assistant in Liebig's laboratory, and in 1843, became an assistant professor.
In 1845, he was appointed to the chair of chemistry, physics and technology at the Wiesbaden Agricultural Institution, and three years later, he became the first director of the chemical laboratory which he induced the Nassau government to establish at that place. Under his leadership and direction, this laboratory continuously increased in size and popularity, a school of pharmacy being added in 1862 (though given up in 1877) and an agricultural research laboratory in 1868.
Apart from his administrative duties, Fresenius occupied himself almost exclusively with analytical chemistry, and the fullness and accuracy of his textbooks on that subject (of which that on qualitative analysis first appeared in 1841 and that on quantitative in 1846) soon rendered them standard works. Many of Fresenius's original papers were published in the Zeitschrift für analytische Chemie, which he founded in 1862 and continued to edit until his death.
Remarkably this journal (also known as Fresenius' Zeitschrift für Analytische Chemie or Fresenius' Journal of Analytica
|
https://en.wikipedia.org/wiki/Corner%20solution
|
In mathematics and economics, a corner solution is a special solution to an agent's maximization problem in which the quantity of one of the arguments in the maximized function is zero. In non-technical terms, a corner solution is when the chooser is either unwilling or unable to make a trade-off between goods.
In economics
In the context of economics the corner solution is best characterised by when the highest indifference curve attainable is not tangential to the budget line, in this scenario the consumer puts their entire budget into purchasing as much of one of the goods as possible and none of any other. When the slope of the indifference curve is greater than the slope of the budget line, the consumer is willing to give up more of good 1 for a unit of good 2 than is required by the market. Thus, it follows that if the slope of the indifference curve is strictly greater than the slope of the budget line:
Then the result will be a corner solution intersecting the x-axis. The converse is also true for a corner solution resulting from an intercept through the y-axis.
Examples
Real world examples of a corner solution occur when someone says "I wouldn't buy that at any price", "Why would I buy X when Y is cheaper" or "I will do X no matter the cost" , this could be for any number of reasons e.g. a bad brand experience, loyalty to a specific brand or when a cheaper version of the same good exists.
Another example is "zero-tolerance" policies, such as a parent who is unw
|
https://en.wikipedia.org/wiki/Nurse%20cell
|
In general biology or reproductive physiology, a nurse cell is a cell which provides food, helps other cells and provides stability to neighboring cells. The term nurse cell is used in several unrelated ways in different scientific fields.
Human physiology
Nurse cells are specialized macrophages residing in the bone marrow that assist in the development of red blood cells. They absorb the nuclei of immature red blood cells and may provide growth factors to help the red blood cells mature. In the bone marrow, immature red blood cells (erythroblasts) can be seen grouped in a cluster around a nurse cell.
The epithelial cell found in the cortex of the thymus is also called a "nurse cell." These cells produce Thymic hormones that cause T lymphocytes to mature and differentiate.
Parasitology
In parasitology, a nurse cell is an infected cell in the disease trichinosis discovered by Dickson Despommier. A trichinella larva enters a cell and develops there, probably as a way of concealing itself from the immune system. The parasite has evolved a way of stimulating blood vessel development around the cell, in order to receive the nutrients it needs. In trichinosis, nurse cells are invariably skeletal muscle cells; these are the only type of cell that can support the parasite.
Mycology
In mycology, a nurse cell is any hyphae that supplies food material to spores that have detached from the basidia; used especially in reference to taxa from the family Sclerodermataceae.
Cell biolo
|
https://en.wikipedia.org/wiki/International%20Conference%20on%20Photonic%2C%20Electronic%20and%20Atomic%20Collisions
|
ICPEAC, the International Conference on Photonic, Electronic and Atomic Collisions, is a biennial scientific conference. It is held in late July. The first conference was held in New York City in 1958. Since then it has been held in the following locations:
References
Physics conferences
|
https://en.wikipedia.org/wiki/Forward%20secrecy
|
In cryptography, forward secrecy (FS), also known as perfect forward secrecy (PFS), is a feature of specific key-agreement protocols that gives assurances that session keys will not be compromised even if long-term secrets used in the session key exchange are compromised. For HTTPS, the long-term secret is typically the private key of the server. Forward secrecy protects past sessions against future compromises of keys or passwords. By generating a unique session key for every session a user initiates, the compromise of a single session key will not affect any data other than that exchanged in the specific session protected by that particular key. This by itself is not sufficient for forward secrecy which additionally requires that a long-term secret compromise does not affect the security of past session keys.
Forward secrecy protects data on the transport layer of a network that uses common transport layer security protocols, including OpenSSL, when its long-term secret keys are compromised, as with the Heartbleed security bug. If forward secrecy is used, encrypted communications and sessions recorded in the past cannot be retrieved and decrypted should long-term secret keys or passwords be compromised in the future, even if the adversary actively interfered, for example via a man-in-the-middle (MITM) attack.
The value of forward secrecy is that it protects past communication. This reduces the motivation for attackers to compromise keys. For instance, if an attacker learn
|
https://en.wikipedia.org/wiki/Neutron%20cross%20section
|
In nuclear physics, the concept of a neutron cross section is used to express the likelihood of interaction between an incident neutron and a target nucleus. The neutron cross section σ can be defined as the area in cm2 for which the number of neutron-nuclei reactions taking place is equal to the product of the number of incident neutrons that would pass through the area and the number of target nuclei. In conjunction with the neutron flux, it enables the calculation of the reaction rate, for example to derive the thermal power of a nuclear power plant. The standard unit for measuring the cross section is the barn, which is equal to 10−28 m2 or 10−24 cm2. The larger the neutron cross section, the more likely a neutron will react with the nucleus.
An isotope (or nuclide) can be classified according to its neutron cross section and how it reacts to an incident neutron. Nuclides that tend to absorb a neutron and either decay or keep the neutron in its nucleus are neutron absorbers and will have a capture cross section for that reaction. Isotopes that undergo fission are fissionable fuels and have a corresponding fission cross section. The remaining isotopes will simply scatter the neutron, and have a scatter cross section. Some isotopes, like uranium-238, have nonzero cross sections of all three.
Isotopes which have a large scatter cross section and a low mass are good neutron moderators (see chart below). Nuclides which have a large absorption cross section are neutron poison
|
https://en.wikipedia.org/wiki/Royal%20Ann%20cherry
|
The Royal Ann or Royal Anne (also called Napoleon, Napoleon Bigarreau and Queen Anne) is a variety of cherry, similar in appearance and taste to the 'Rainier cherry'.
Biology
About Royal Ann
Royal Ann cherry trees are perennial semi-dwarfs that bloom early April with harvest in mid-summer. They are deciduous trees that can be characterized by dark green leaves and clusters of small fragrant white flowers that are about 2.5-3 centimeters wide. Royal Ann flowers are hermaphroditic, containing both male and female reproductive organs, however, the tree cannot self-pollinate. Another pollinator species is necessary in order for fertilization to occur, most commonly bees. Each flower goes on to produce a single Royal Ann cherry. A mature fruit producing Royal Ann tree is about 12–15 feet in height. The trees prefer a half to full day of sun, and soil with good drainage. Royal Ann trees require a temperate climate, where the average winter temperature does not drop below 10 degrees Fahrenheit.
Royal Ann cherries are fleshy stone fruits similar in size to most cherry varieties, and are yellow to light pink colored. Royal Ann fruits are often mistaken for Rainier cherries because of their similar appearance and taste. Trees produce fruit within 1–3 years after planting and are considered fully mature around 8 years old. Royal Ann trees can produce up to 50 pounds of cherries per season.
Nutrient content
Cherries are famous for containing high levels of antioxidants, which are s
|
https://en.wikipedia.org/wiki/Dihydrogen%20bond
|
In chemistry, a dihydrogen bond is a kind of hydrogen bond, an interaction between a metal hydride bond and an OH or NH group or other proton donor. With a van der Waals radius of 1.2 Å, hydrogen atoms do not usually approach other hydrogen atoms closer than 2.4 Å. Close approaches near 1.8 Å, are, however, characteristic of dihydrogen bonding.
Boron hydrides
An early example of this phenomenon is credited to Brown and Heseltine. They observed intense absorptions in the IR bands at 3300 and 3210 cm−1 for a solution of (CH3)2NHBH3. The higher energy band is assigned to a normal N−H vibration whereas the lower energy band is assigned to the same bond, which is interacting with the B−H. Upon dilution of the solution, the 3300 cm−1 band increased in intensity and the 3210 cm−1 band decreased, indicative of intermolecular association.
Interest in dihydrogen bonding was reignited upon the crystallographic characterization of the molecule H3NBH3. In this molecule, like the one studied by Brown and Hazeltine, the hydrogen atoms on nitrogen have a partial positive charge, denoted Hδ+, and the hydrogen atoms on boron have a partial negative charge, often denoted Hδ−. In other words, the amine is a protic acid and the borane end is hydridic. The resulting B−H...H−N attractions stabilize the molecule as a solid. In contrast, the related substance ethane, H3CCH3, is a gas with a boiling point 285 °C lower. Because two hydrogen centers are involved, the interaction is termed a dih
|
https://en.wikipedia.org/wiki/Parietaria%20officinalis
|
Parietaria officinalis, the eastern pellitory-of-the-wall, also known as upright pellitory and lichwort, is a plant of the nettle family. Its leaves, however, are non-stinging. The plant grows on rubbish and on walls, hence the name.
The pollen is a cause of allergy.
Uses
It was once used in the making of certain metheglins.
Chemistry
The leaves and flowers of P. officinalis contains the flavonoids kaempferol-3-bioside, the 3-glucosides and 3-rutinosides of quercetin, kaempferol and isorhamnetin, 3-sophorosides of quercetin and kaempferol and 3-neohesperosides of kaempferol and isorhamnetin. They also contain caffeoylmalic and two pyrrole acids.
See also
It is in a different family from Anacyclus pyrethrum, also called pellitory.
References
External links
officinalis
Medicinal plants
Plants described in 1753
Taxa named by Carl Linnaeus
|
https://en.wikipedia.org/wiki/Philip%20M.%20Morse
|
Philip McCord Morse (August 6, 19035 September 1985), was an American physicist, administrator and pioneer of operations research (OR) in World War II. He is considered to be the father of operations research in the U.S.
Biography
Morse graduated from the Case School of Applied Science in 1926 with a B.S. in physics. He earned his Ph.D. in physics from Princeton University in 1929. In 1930, he was granted an International Fellowship, which he used to do postgraduate study and research at the Ludwig Maximilian University of Munich under Arnold Sommerfeld during the winter of 1930 to the spring of 1931.
From the spring through the summer of 1931, he was at Cambridge University. Upon return to the United States, he joined the faculty of MIT.
In 1949 he was named the first research director of the Weapons Systems Evaluation Group (WSEG), an organization founded to conduct studies for the Joint Chiefs of Staff, where he served a year and a half before returning to MIT in the summer of 1950. In 1956 he launched MIT’s operations research center, directing it until 1968, and awarding the first Ph.D. in operations research in the U.S. to John Little.
He was a member of a National Research Council committee dedicated to bringing OR into civilian life, and was a prime mover behind the creation of the Operations Research Society of America (ORSA) in 1952. He served as president of the American Physical Society, president of the Acoustical Society of America (ASA), and board chair o
|
https://en.wikipedia.org/wiki/Helicene
|
In organic chemistry, helicenes are ortho-condensed polycyclic aromatic compounds in which benzene rings or other aromatics are angularly annulated to give helically-shaped chiral molecules. The chemistry of helicenes has attracted continuing attention because of their unique structural, spectral, and optical features.
Structure and properties
The systematic naming for this class of compounds is based on the number of rings: [n]helicene is the structure consisting of n rings. According to IUPAC, only structures where n is at least 5 are considered helicenes. Some specific compounds also have alternate or trivial names. As the number of rings increases, starting at four, the structure becomes non-planar, but instead the planes of consecutive rings tilt to prevent steric collisions. The resulting helix is chiral. For helicenes with six benzene units, a 360° turn is completed. In the helicene series the dihedral angles between the extremities increases going from [4]helicene (26°) to [6]helicene (58°) and then decreases again for example in [7]helicene (30°).
Helicenes are notable for having chirality despite lacking both asymmetric carbons and chiral centers. Instead, there is axial chirality, which results from the handedness of the helicity itself. The clockwise and counterclockwise helices are non-superposable. By convention a left-handed helix is minus and labeled (M), a right-handed helix is plus and labeled (P). Evidence from CD spectroscopy suggests left-handed helices
|
https://en.wikipedia.org/wiki/EES
|
EES may refer to:
Education
Electrical Engineering Society or EES, a popular student chapter in Sardar Vallabhbhai National Institute of Technology, Surat
Government
Entry/Exit System, a proposed biometric database in the European Union
European Economic Senate
European Employment Strategy
Places
Ees (place name), an archaic term for water meadows or firm land adjacent to streams or fens
Ees, Drenthe, a village in the Netherlands
Eys (), a village in Limburg, Netherlands
Science and medicine
Egypt Exploration Society, an archeological society
Endoscopic ear surgery
Energy & Environmental Science, a scholarly journal
Environmental engineering science
Epidural electrical stimulator, a type of spinal cord stimulator
Ethinylestradiol sulfonate
Extended evolutionary synthesis
Technology
Engineering Equation Solver, a thermodynamics software package
Other uses
EES (rapper) (born 1983), Namibian musician
Electric Eel Shock, a Japanese rock band
Enron Energy Services, an American energy distribution company
See also
ES (disambiguation)
EE (disambiguation)
|
https://en.wikipedia.org/wiki/Bosque%20School
|
Bosque School is an independent, co-educational, college preparatory school for grades 6–12 founded in 1994. The school sits on a site along the Rio Grande bosque in Albuquerque, New Mexico. Surrounded by the riparian forest of the bosque, the school emphasizes environmental science, the arts, and service learning. With 550 students and 60 teaching faculty, there is a 9:1 student/faculty ratio. An average class size at Bosque School is 16 students. The school is accredited by the Independent Schools Association of the Southwest and is a member of NAIS, NACAC, NMAA, APIAL and other associations. Bosque School was voted the #1 private school in Albuquerque by the 2020 Albuquerque Journal Reader's Choice Awards. The annual summer camp program at the school, Bosque Summer, was voted #1 at the same awards.
History
Bosque School was established in 1994. Dr. Gary Gruber was appointed as the first principal.
In August 1995, Bosque Preparatory School opened in a rented space in Albuquerque's Northeast Heights with 72 sixth and seventh grade students and Dr. Gary Gruber as its first school principal.
In 1996, the Bosque Ecosystem Monitoring Program (BEMP) began as a collaboration between the Biology Department of the University of New Mexico and the Black Institute for Environmental Studies at Bosque School.
In 1998, President Gerald R. Ford and his family assisted in launching the school's first capital campaign, through which almost $1 million was secured to begin construction
|
https://en.wikipedia.org/wiki/Paul%20Noug%C3%A9
|
Paul Nougé (12 February 1895 – 6 November 1967) was a Belgian poet, founder and theoretician of surrealism in Belgium, sometimes known as the "Belgian Breton".
Biography
Born of a French father who originated from the Charent region in France and a Belgian mother, Paul Nougé attended a French school in Brussels studying Biological Chemistry and worked as a Biochemist in a medical laboratory from 1919 to 1953. He became a founding member of the first Belgian Communist Party in 1919. In November 1924 he created the journal Correspondance, which published 26 pamphlets up to September 1925, in collaboration with Camille Goemans and Marcel Lecomte. In July 1925 he was expelled from the party. That same year Nougé met the French surrealists, Louis Aragon, André Breton and Paul Éluard, and together they signed the tract "La Révolution d'abord et toujours" (The Revolution First and Forever). In 1926 he made the acquaintance of Louis Scutenaire, and September of that year marked the drafting of the constitution of the Belgian Surrealist Group that comprised Nougé, Goemans, René Magritte, E. L. T. Mesens and André Souris.
In 1927 Nougé composed plagiarised examples of a grammar book of Clarisse Juranville, illustrated with five drawings by Magritte. In 1928 he founded the magazine Distances and wrote the poem catalogue of a fur trader that was illustrated by Magritte entitled Le catalogue Samuel (re-edited by Didier Devillez, Brussels, 1996). He also wrote the preface of a Magrit
|
https://en.wikipedia.org/wiki/Lee%20M.%20Silver
|
Lee M. Silver (born 1952) is an American biologist. He is a professor at Princeton University in the Department of molecular biology and the Princeton School of Public and International Affairs. He also has joint appointments in the Program in Science, Technology, and Environmental Policy, the Center for Health and Wellbeing, the Office of Population Research, and the Princeton Environmental Institute, all at Princeton University.
Silver is the author of the book Remaking Eden: How Genetic Engineering and Cloning Will Transform the American Family (1998). In the book he takes a positive view on human cloning, designer babies and similar prospects. In this book he coined the term reprogenetics to describe the prospective fusion of reproductive technologies and genetics, which will allow positive eugenic actions on an individual level.
His most recent book, Challenging Nature: The Clash of Science and Spirituality at the New Frontiers of Life, was released in June 2006.
Silver is the co-founder of GenePeeks, a genetic research company which owns a simulation for screening genetic disorders.
References
External links
Interview on Books and Ideas Podcast, 2007
Video of interview/discussion with Lee M. Silver by Carl Zimmer on Bloggingheads.tv
1952 births
Living people
21st-century American biologists
Princeton University faculty
Central High School (Philadelphia) alumni
|
https://en.wikipedia.org/wiki/Decomposition%20%28computer%20science%29
|
Decomposition in computer science, also known as factoring, is breaking a complex problem or system into parts that are easier to conceive, understand, program, and maintain.
Overview
There are different types of decomposition defined in computer sciences:
In structured programming, algorithmic decomposition breaks a process down into well-defined steps.
Structured analysis breaks down a software system from the system context level to system functions and data entities as described by Tom DeMarco.<ref>Tom DeMarco (1978). Structured Analysis and System Specification. New York, NY: Yourdon, 1978. , .</ref>
Object-oriented decomposition, on the other hand, breaks a large system down into progressively smaller classes or objects that are responsible for some part of the problem domain.
According to Booch, algorithmic decomposition is a necessary part of object-oriented analysis and design, but object-oriented systems start with and emphasize decomposition into objects.
More generally, functional decomposition in computer science is a technique for mastering the complexity of the function of a model. A functional model of a system is thereby replaced by a series of functional models of subsystems.
Decomposition topics
Decomposition paradigm
A decomposition paradigm in computer programming is a strategy for organizing a program as a number of parts, and it usually implies a specific way to organize a program text. Usually the aim of using a decomposition paradigm is
|
https://en.wikipedia.org/wiki/Gertrud%20Sch%C3%BCpbach
|
Trudi Schüpbach (born Zurich, Switzerland, February 3, 1950; full name Gertrud M. Schüpbach; published name Trudi Schüpbach) is a Swiss-American molecular biologist. She is an Emeritus Professor of Molecular Biology at Princeton University, where her laboratory studies molecular and genetic mechanisms in fruit fly (Drosophila melanogaster) oogenesis.
Research
Schüpbach's research focuses on signaling pathways that are involved in pattern formation during embryonic development. Using the fruit fly (Drosophila melanogaster) as a model system, she revealed molecular mechanisms underlying the determination of the major axis of the embryo. Performing genetic screens, she identified mutants that result in female sterility of which many affect embryonic body patterning. By that, she contributed to the understanding of maternal factors that are deposited into the forming egg during oogenesis and that are conferred into spatial information within the developing embryo to demarcate distinct functional regions.
Life
Schüpbach received her Ph.D. in Biology from the University of Zurich, Switzerland, where she also performed her first postdoctoral work before she continued as a postdoc at Princeton University. In 1990 she was appointed as Associate Professor and promoted to Full Professor in 1994 at Princeton University. Schüpbach is married to Nobel laureate and fellow biologist Eric F. Wieschaus.
Honors
1981 Alfred Schlafli Prize for thesis research awarded by Swiss Zoological
|
https://en.wikipedia.org/wiki/Software%20Bisque
|
Software Bisque, Inc. (formerly named Computer Assist Services) is a corporation based in Golden, Colorado that develops robotics telescope mounts and accessories and publishes software used in astronomy. It was founded in 1984 by current president and CEO, Stephen M. Bisque.
History
Bisque initially developed and marketed custom financial software and also sold a DOS-based astronomy program named TheSky. At that time, the company was based in Bisque's home in Golden, Colorado.
In 1990, Bisque hired his brothers Thomas, Daniel and Matthew. Together they ported TheSky for DOS to Windows 3.0. In 1992, TheSky for Windows was released. The product has been under continuous development since it was first released in the early 1980s; the current version is known as TheSkyX.
Products
Software Bisque has since developed and sold many astronomy-related products, including:
TheSky, TheSkyX Astronomy Software, Camera Add On, Dome Add On, and TPoint Add On
TheSky Pocket Edition for Windows Mobile devices
CCDSoft, a program for the acquisition and development of CCD images
TPoint for Windows, telescope analysis and pointing correction software
Orchestrate, a program for automating multiple astronomy devices, allowing fully automatic operation and data acquisition
Seeker, an OpenGL three-dimensional solar system simulator
AutomaDome, astronomical dome control software
PrecisionPEC, periodic error correction modeling software
Paramount ME, Paramount ME II, Paramount MX, Paramount MYT Ger
|
https://en.wikipedia.org/wiki/Actor%20model%20theory
|
In theoretical computer science, Actor model theory concerns theoretical issues for the Actor model.
Actors are the primitives that form the basis of the Actor model of concurrent digital computation. In response to a message that it receives, an Actor can make local decisions, create more Actors, send more messages, and designate how to respond to the next message received. Actor model theory incorporates theories of the events and structures of Actor computations, their proof theory, and denotational models.
Events and their orderings
From the definition of an Actor, it can be seen that numerous events take place: local decisions, creating Actors, sending messages, receiving messages, and designating how to respond to the next message received.
However, this article focuses on just those events that are the arrival of a message sent to an Actor.
This article reports on the results published in Hewitt [2006].
Law of Countability: There are at most countably many events.
Activation ordering
The activation ordering (-≈→) is a fundamental ordering that models one event activating another (there must be energy flow in the message passing from an event to an event which it activates).
Because of the transmission of energy, the activation ordering is relativistically invariant; that is, for all events e1.e2, if e1 -≈→ e2, then the time of e1 precedes the time of e2 in the relativistic frames of reference of all observers.
Law of Strict Causality for the Activation Order
|
https://en.wikipedia.org/wiki/Actor%20model%20implementation
|
In computer science, Actor model implementation concerns implementation issues for the Actor model.
Cosmic Cube
The Caltech Cosmic Cube was developed by Chuck Seitz et al. at Caltech providing architectural support for Actor systems. A significant difference between the Cosmic Cube and
most other parallel processors is that this multiple instruction
multiple-data machine uses message passing
instead of shared variables for communication between
concurrent processes. This computational model is reflected
in the hardware structure and operating system,
and is also the explicit message passing communication seen by the programmer. According to Seitz [1985]:
It was a premise of the Cosmic Cube experiment that the internode communication should scale well to very large numbers of nodes. A direct network like the hypercube satisfies this requirement, with respect to both the aggregate bandwidth achieved across the many concurrent communication channels and the feasibility of the implementation. The hypercube is actually a distributed variant of an indirect logarithmic switching network like the Omega or banyan networks: the kind that might be used in shared-storage organizations. With the hypercube, however, communication paths traverse different numbers of channels and so exhibit different latencies. It is possible, therefore, to take advantage of communication locality in placing processes in nodes.
J–Machine
The J–Machine was developed by Bill Dally et al. at MIT providing
|
https://en.wikipedia.org/wiki/Jacutinga
|
Jacutinga may refer to:
Biology
Black-fronted piping guan, or jacutinga, a New World bird
Places
Jacutinga, Minas Gerais Brazil
Jacutinga, Rio Grande do Sul, Brazil
Santa Rita de Jacutinga, Minas Gerais, Brazil
|
https://en.wikipedia.org/wiki/Resultant
|
In mathematics, the resultant of two polynomials is a polynomial expression of their coefficients that is equal to zero if and only if the polynomials have a common root (possibly in a field extension), or, equivalently, a common factor (over their field of coefficients). In some older texts, the resultant is also called the eliminant.
The resultant is widely used in number theory, either directly or through the discriminant, which is essentially the resultant of a polynomial and its derivative. The resultant of two polynomials with rational or polynomial coefficients may be computed efficiently on a computer. It is a basic tool of computer algebra, and is a built-in function of most computer algebra systems. It is used, among others, for cylindrical algebraic decomposition, integration of rational functions and drawing of curves defined by a bivariate polynomial equation.
The resultant of n homogeneous polynomials in n variables (also called multivariate resultant, or Macaulay's resultant for distinguishing it from the usual resultant) is a generalization, introduced by Macaulay, of the usual resultant. It is, with Gröbner bases, one of the main tools of elimination theory.
Notation
The resultant of two univariate polynomials and is commonly denoted or
In many applications of the resultant, the polynomials depend on several indeterminates and may be considered as univariate polynomials in one of their indeterminates, with polynomials in the other indeterminates as c
|
https://en.wikipedia.org/wiki/Rational%20zeta%20series
|
In mathematics, a rational zeta series is the representation of an arbitrary real number in terms of a series consisting of rational numbers and the Riemann zeta function or the Hurwitz zeta function. Specifically, given a real number x, the rational zeta series for x is given by
where qn is a rational number, the value m is held fixed, and ζ(s, m) is the Hurwitz zeta function. It is not hard to show that any real number x can be expanded in this way.
Elementary series
For integer m>1, one has
For m=2, a number of interesting numbers have a simple expression as rational zeta series:
and
where γ is the Euler–Mascheroni constant. The series
follows by summing the Gauss–Kuzmin distribution. There are also series for π:
and
being notable because of its fast convergence. This last series follows from the general identity
which in turn follows from the generating function for the Bernoulli numbers
Adamchik and Srivastava give a similar series
Polygamma-related series
A number of additional relationships can be derived from the Taylor series for the polygamma function at z = 1, which is
.
The above converges for |z| < 1. A special case is
which holds for |t| < 2. Here, ψ is the digamma function and ψ(m) is the polygamma function. Many series involving the binomial coefficient may be derived:
where ν is a complex number. The above follows from the series expansion for the Hurwitz zeta
taken at y = −1. Similar series may be obtained by simple algebra:
and
and
|
https://en.wikipedia.org/wiki/Actor%20model%20and%20process%20calculi
|
In computer science, the Actor model and process calculi are two closely related approaches to the modelling of concurrent digital computation. See Actor model and process calculi history.
There are many similarities between the two approaches, but also several differences (some philosophical, some technical):
There is only one Actor model (although it has numerous formal systems for design, analysis, verification, modeling, etc.); there are numerous process calculi, developed for reasoning about a variety of different kinds of concurrent systems at various levels of detail (including calculi that incorporate time, stochastic transitions, or constructs specific to application areas such as security analysis).
The Actor model was inspired by the laws of physics and depends on them for its fundamental axioms, i.e. physical laws (see Actor model theory); the process calculi were originally inspired by algebra .
Processes in the process calculi are anonymous, and communicate by sending messages either through named channels (synchronous or asynchronous), or via ambients (which can also be used to model channel-like communications ). In contrast, actors in the Actor model possess an identity, and communicate by sending messages to the mailing addresses of other actors (this style of communication can also be used to model channel-like communications—see below).
The publications on the Actor model and on process calculi have a fair number of cross-references, acknowledgments, a
|
https://en.wikipedia.org/wiki/Burkard%20Hillebrands
|
Burkard Hillebrands (born 1957) is a German physicist and professor of physics. He is the leader of the magnetism research group in the Department of Physics at the Technische Universität Kaiserslautern.
Academic career
Burkard Hillebrands was born in 1957. He studied physics at the University of Cologne (1977–1982) and was awarded his PhD in 1986 at the University of Cologne under the supervision of Gernot Güntherodt.
After a postdoctoral stay at the Optical Sciences Center in Tucson, Arizona he received his habilitation from the RWTH Aachen in 1993. He was employed as an associate professor at the University of Karlsruhe in 1994. In 1995 he accepted a full professor position at the Technische Universität Kaiserslautern. Between 2006 and 2014, he served as the Vice President for Research, Technology and Innovation of the Technische Universität Kaiserslautern. He is a member of the Academy of Science and Literature Mainz and since 2017 has been its vice president and chair of the Commission for Mathematics and Physical Sciences. Since 2018 he is member of the National Academy of Science and Engineering (acatech). Hillebrands was the Scientific Director and Chairman of the Executive Board of the Leibniz Institute for Solid State and Materials Research (IFW), Dresden for the period from July 2016 to March 2018.
He serves or has served as either chairperson or vice-chairperson in various coordinated initiatives of the German Science Foundation and the European Community,
|
https://en.wikipedia.org/wiki/Gauss%E2%80%93Kuzmin%20distribution
|
In mathematics, the Gauss–Kuzmin distribution is a discrete probability distribution that arises as the limit probability distribution of the coefficients in the continued fraction expansion of a random variable uniformly distributed in (0, 1). The distribution is named after Carl Friedrich Gauss, who derived it around 1800, and Rodion Kuzmin, who gave a bound on the rate of convergence in 1929. It is given by the probability mass function
Gauss–Kuzmin theorem
Let
be the continued fraction expansion of a random number x uniformly distributed in (0, 1). Then
Equivalently, let
then
tends to zero as n tends to infinity.
Rate of convergence
In 1928, Kuzmin gave the bound
In 1929, Paul Lévy improved it to
Later, Eduard Wirsing showed that, for λ = 0.30366... (the Gauss–Kuzmin–Wirsing constant), the limit
exists for every s in [0, 1], and the function Ψ(s) is analytic and satisfies Ψ(0) = Ψ(1) = 0. Further bounds were proved by K. I. Babenko.
See also
Khinchin's constant
Lévy's constant
References
Continued fractions
Discrete distributions
|
https://en.wikipedia.org/wiki/Zeta%20function%20universality
|
In mathematics, the universality of zeta functions is the remarkable ability of the Riemann zeta function and other similar functions (such as the Dirichlet L-functions) to approximate arbitrary non-vanishing holomorphic functions arbitrarily well.
The universality of the Riemann zeta function was first proven by in 1975 and is sometimes known as Voronin's universality theorem.
Formal statement
A mathematically precise statement of universality for the Riemann zeta function ζ(s) follows.
Let U be a compact subset of the strip
such that the complement of U is connected. Let be a continuous function on U which is holomorphic on the interior of U and does not have any zeros in U. Then for any there exists a such that
for all .
Even more: the lower density of the set of values t satisfying the above inequality is positive. Precisely
where denotes the Lebesgue measure on the real numbers and denotes the limit inferior.
Discussion
The condition that the complement of U be connected essentially means that U does not contain any holes.
The intuitive meaning of the first statement is as follows: it is possible to move U by some vertical displacement it so that the function f on U is approximated by the zeta function on the displaced copy of U, to an accuracy of ε.
The function f is not allowed to have any zeros on U. This is an important restriction; if we start with a holomorphic function with an isolated zero, then any "nearby" holomorphic function will also have a z
|
https://en.wikipedia.org/wiki/Denice%20Denton
|
Denice Dee Denton (August 27, 1959 – June 24, 2006) was an American professor of electrical engineering and academic administrator. She was the ninth chancellor of the University of California, Santa Cruz.
Biography
Early years
Denton was born in El Campo, Texas, in Wharton County. She was the oldest child of Bob Glenn Denton and Carolyn Irene Drab. Denton earned her bachelor's and master's degrees (1982), EE (1983) and PhD (1987) in electrical engineering from the Massachusetts Institute of Technology. Denton spent two summers and an academic year in the late 1970s and early 1980s at Fairchild Semiconductor, where her projects included 64K static RAM design. After graduation, she accepted a professorship at the University of Wisconsin–Madison in the Department of Computer and Electrical Engineering, which was interested in her work in plasma deposition and polymerization. She was the first woman to win tenure in engineering, and she was quickly promoted to full professor.
Career
Denton held academic appointments at the University of Massachusetts Lowell and the Swiss Federal Institute of Technology in Zürich. In 1996, Denton was hired as the Dean of the College of Engineering and professor of electrical engineering at the University of Washington. She was the first woman in the United States to lead an engineering college of a major research university.
Denton received attention for her response to Harvard President Larry Summers' suggestion, in January 2005, that one o
|
https://en.wikipedia.org/wiki/Phosphaalkyne
|
In chemistry, a phosphaalkyne (IUPAC name: alkylidynephosphane) is an organophosphorus compound containing a triple bond between phosphorus and carbon with the general formula R-C≡P. Phosphaalkynes are the heavier congeners of nitriles, though, due to the similar electronegativities of phosphorus and carbon, possess reactivity patterns reminiscent of alkynes. Due to their high reactivity, phosphaalkynes are not found naturally on earth, but the simplest phosphaalkyne, phosphaethyne (H-C≡P) has been observed in the interstellar medium.
Synthesis
From phosphine gas
The first of preparation of a phosphaalkyne was achieved in 1961 when Thurman Gier produced phosphaethyne by passing phosphine gas at low pressure over an electric arc produced between two carbon electrodes. Condensation of the gaseous products in a –196 °C (–321 °F) trap revealed that the reaction had produced acetylene, ethylene, phosphaethyne, which was identified by infrared spectroscopy.
By elimination reactions
Elimination of hydrogen halides
Following the initial synthesis of phosphaethyne, it was realized that the same compound can be prepared more expeditiously via the flash pyrolysis of methyldichlorophosphine (CH3PCl2), resulting in the loss of two equivalents of hydrogen chloride. This methodology has been utilized to synthesize numerous substituted phosphaalkynes, including the methyl, vinyl, chloride, and fluoride derivatives. Fluoromethylidynephosphane (F-C≡P) can also be prepared via the potass
|
https://en.wikipedia.org/wiki/Potassium%20fluoride
|
Potassium fluoride is the chemical compound with the formula KF. After hydrogen fluoride, KF is the primary source of the fluoride ion for applications in manufacturing and in chemistry. It is an alkali halide salt and occurs naturally as the rare mineral carobbiite. Solutions of KF will etch glass due to the formation of soluble fluorosilicates, although HF is more effective.
Preparation
Potassium fluoride is prepared by reacting potassium carbonate with hydrofluoric acid. Evaporation of the solution forms crystals of potassium bifluoride. The bifluoride on heating yields potassium fluoride:
K2CO3 + 4HF -> 2KHF2 + CO2 ^ + H2O
KHF2 -> KF + HF ^
Platinum or heat resistant plastic containers are often used for these operations.
Potassium chloride converts to KF upon treatment with hydrogen fluoride. In this way, potassium fluoride is recyclable.
Crystalline properties
KF crystallizes in the cubic NaCl crystal structure. The lattice parameter at room temperature is 0.266 nm.
Applications in organic chemistry
In organic chemistry, KF can be used for the conversion of chlorocarbons into fluorocarbons, via the Finkelstein (alkyl halides) and Halex reactions (aryl chlorides). Such reactions usually employ polar solvents such as dimethyl formamide, ethylene glycol, and dimethyl sulfoxide. More efficient fluorination of aliphatic halides can be achieved with a combination of crown ether and bulky diols in acetonitrile solvent.
Safety considerations
Like other sources of t
|
https://en.wikipedia.org/wiki/Herbert%20McCabe
|
Herbert John Ignatius McCabe (2 August 192628 June 2001) was a Dominican priest, theologian and philosopher.
Biography
Herbert McCabe was born in Middlesbrough in the North Riding of Yorkshire. He studied chemistry at Manchester University, but influenced by Dorothy Emmet switched to philosophy. He contributed a number of pieces to Humanitas, and became friends with Eric John among others.
McCabe joined the Dominicans in 1949, where under Victor White he began his lifelong study of the works of Thomas Aquinas. Born John Ignatius McCabe, he had as his novice master, Columba Ryan, who gave McCabe the religious name Herbert, in honour of Herbert of Derwentwater, a seventh-century Lakeland hermit. Ordained in 1955, he was a pastor in Newcastle for three years before being assigned as chaplain to De La Salle College, where one of his pupils was Terry Eagleton.
In 1965, he was sent to Cambridge as editor of the journal New Blackfriars but was removed in 1967 following a now-famous editorial in that journal in which he criticised the theologian Charles Davis for having left the Catholic Church. Davis left publicly, denouncing the church as corrupt. McCabe countered that of course the Church was corrupt but that this was no reason to leave it. Fr McCabe moved to Dublin, Ireland during the controversy. He was reinstated three years later, and began his editorial that month in characteristically combative style: "As I was saying, before I was so oddly interrupted..." He spent ma
|
https://en.wikipedia.org/wiki/Front%20velocity
|
In physics, front velocity is the speed at which the first rise of a pulse above zero moves forward.
In mathematics, it is used to describe the velocity of a propagating front in the solution of hyperbolic partial differential equation.
Various velocities
Associated with propagation of a disturbance are several different velocities. For definiteness, consider an amplitude modulated electromagnetic carrier wave. The phase velocity is the speed of the underlying carrier wave. The group velocity is the speed of the modulation or envelope. Initially it was thought that the group velocity coincided with the speed at which information traveled. However, it turns out that this speed can exceed the speed of light in some circumstances, causing confusion by an apparent conflict with the theory of relativity. That observation led to consideration of what constitutes a signal.
By definition, a signal involves new information or an element of 'surprise' that cannot be predicted from the wave motion at an earlier time. One possible form for a signal (at the point of emission) is:
where u(t) is the Heaviside step function. Using such a form for a signal, it can be shown, subject to the (expected) condition that the refractive index of any medium tends to one as the frequency tends to infinity, that the wave discontinuity, called the front, propagates at a speed less than or equal to the speed of light c in any medium. In fact, the earliest appearance of the front of an electromagneti
|
https://en.wikipedia.org/wiki/Selberg%20class
|
In mathematics, the Selberg class is an axiomatic definition of a class of L-functions. The members of the class are Dirichlet series which obey four axioms that seem to capture the essential properties satisfied by most functions that are commonly called L-functions or zeta functions. Although the exact nature of the class is conjectural, the hope is that the definition of the class will lead to a classification of its contents and an elucidation of its properties, including insight into their relationship to automorphic forms and the Riemann hypothesis. The class was defined by Atle Selberg in , who preferred not to use the word "axiom" that later authors have employed.
Definition
The formal definition of the class S is the set of all Dirichlet series
absolutely convergent for Re(s) > 1 that satisfy four axioms (or assumptions as Selberg calls them):
Comments on definition
The condition that the real part of μi be non-negative is because there are known L-functions that do not satisfy the Riemann hypothesis when μi is negative. Specifically, there are Maass forms associated with exceptional eigenvalues, for which the Ramanujan–Peterssen conjecture holds, and have a functional equation, but do not satisfy the Riemann hypothesis.
The condition that θ < 1/2 is important, as the θ = 1 case includes whose zeros are not on the critical line.
Without the condition there would be which violates the Riemann hypothesis.
It is a consequence of 4. that the an are multiplica
|
https://en.wikipedia.org/wiki/Bulk%20density
|
In materials science, bulk density, also called apparent density, is a material property defined as the mass of the many particles of the material divided by the bulk volume. Bulk volume is defined as the total volume the particles occupy, including particle's own volume, inter-particle void volume, and the particles' internal pore volume.
Bulk density is useful for materials such as powders, granules, and other "divided" solids, especially used in reference to mineral components (soil, gravel), chemical substances, pharmaceutical ingredients, foodstuff, or any other masses of corpuscular or particulate matter (particles).
Bulk density is not the same as the particle density, which is an intrinsic property of the solid and does not include the volume for voids between particles (see: density of non-compact materials).
Bulk density is an extrinsic property of a material; it can change depending on how the material is handled. For example, a powder poured into a cylinder will have a particular bulk density; if the cylinder is disturbed, the powder particles will move and usually settle closer together, resulting in a higher bulk density. For this reason, the bulk density of powders is usually reported both as "freely settled" (or "poured" density) and "tapped" density (where the tapped density refers to the bulk density of the powder after a specified compaction process, usually involving vibration of the container.)
Soil
The bulk density of soil depends greatly on the
|
https://en.wikipedia.org/wiki/Lamellar%20structure
|
In materials science, lamellar structures or microstructures are composed of fine, alternating layers of different materials in the form of lamellae. They are often observed in cases where a phase transition front moves quickly, leaving behind two solid products, as in rapid cooling of eutectic (such as solder) or eutectoid (such as pearlite) systems.
Such conditions force phases of different composition to form but allow little time for diffusion to produce those phases' equilibrium compositions. Fine lamellae solve this problem by shortening the diffusion distance between phases, but their high surface energy makes them unstable and prone to break up when annealing allows diffusion to progress. A deeper eutectic or more rapid cooling will result in finer lamellae; as the size of an individual lamellum approaches zero, the system will instead retain its high-temperature structure. Two common cases of this include cooling a liquid to form an amorphous solid, and cooling eutectoid austenite to form martensite.
In biology, normal adult bones possess a lamellar structure which may be disrupted by some diseases.
References
Membrane biology
Physical chemistry
|
https://en.wikipedia.org/wiki/Defeminization
|
In developmental biology and zoology, defeminization is an aspect of the process of sexual differentiation by which a potential female-specific structure, function, or behavior is changed by one of the processes of male development.
See also
Sexual differentiation
Defeminization and masculinization
Virilization
Feminization
References
Sexual anatomy
Zoology
Physiology
|
https://en.wikipedia.org/wiki/Merkle
|
Merkle and Merckle are surnames of German origin. It used as a minimization of Old German given names such as Markwart (meaning "guard of the frontier") or Markhard (meaning "strong frontier"). They may refer to:
Cryptography and computing
Merkle–Damgård construction, a method of building collision-resistant cryptographic hash functions
Merkle–Hellman knapsack cryptosystem, an early public key cryptosystem
Merkle's Puzzles, an early construction for a public-key cryptosystem
Merkle tree, a computer hash tree
People
Business
Adolphe Merkle (1924–2012), Swiss Entrepreneur and patron of the sciences
Adolf Merckle (19342009), German entrepreneur
Edgar A. Merkle (1900–1984), American founder of Merkle Press in Washington, D.C. and Merkle Wildlife Sanctuary and Visitor's Center on the Patuxent River in Maryland
(19132000), German industrial manager and 1996 winner of the Adenauer-de Gaulle Prize
Ludwig Merckle (born 1965), German businessman
Philipp Daniel Merckle (born 1966), German entrepreneur
Religion
Benjamin L. Merkle, professor at Southeastern Baptist Theological Seminary, North Carolina
Benjamin R. Merkle, president of New Saint Andrews College, Idaho
Sport
Andreas Merkle (born 1962), former German footballer
Ed Merkle (191787), American football player
Fred Merkle (18881956), American baseball player
(1918–1993), German football trainer and coach of 1. FC Köln
Other people
Judith Merkle Riley (19422010), American writer, teacher and academic
Mar
|
https://en.wikipedia.org/wiki/Stickelberger%27s%20theorem
|
In mathematics, Stickelberger's theorem is a result of algebraic number theory, which gives some information about the Galois module structure of class groups of cyclotomic fields. A special case was first proven by Ernst Kummer (1847) while the general result is due to Ludwig Stickelberger (1890).
The Stickelberger element and the Stickelberger ideal
Let denote the th cyclotomic field, i.e. the extension of the rational numbers obtained by adjoining the th roots of unity to (where is an integer). It is a Galois extension of with Galois group isomorphic to the multiplicative group of integers modulo . The Stickelberger element (of level or of ) is an element in the group ring and the Stickelberger ideal (of level or of ) is an ideal in the group ring . They are defined as follows. Let denote a primitive th root of unity. The isomorphism from to is given by sending to defined by the relation
.
The Stickelberger element of level is defined as
The Stickelberger ideal of level , denoted , is the set of integral multiples of which have integral coefficients, i.e.
More generally, if be any Abelian number field whose Galois group over is denoted , then the Stickelberger element of and the Stickelberger ideal of can be defined. By the Kronecker–Weber theorem there is an integer such that is contained in . Fix the least such (this is the (finite part of the) conductor of over ). There is a natural group homomorphism given by restriction, i.e. if , its image
|
https://en.wikipedia.org/wiki/Ligand%20%28biochemistry%29
|
In biochemistry and pharmacology, a ligand is a substance that forms a complex with a biomolecule to serve a biological purpose. The etymology stems from Latin ligare, which means 'to bind'. In protein-ligand binding, the ligand is usually a molecule which produces a signal by binding to a site on a target protein. The binding typically results in a change of conformational isomerism (conformation) of the target protein. In DNA-ligand binding studies, the ligand can be a small molecule, ion, or protein which binds to the DNA double helix. The relationship between ligand and binding partner is a function of charge, hydrophobicity, and molecular structure.
Binding occurs by intermolecular forces, such as ionic bonds, hydrogen bonds and Van der Waals forces. The association or docking is actually reversible through dissociation. Measurably irreversible covalent bonding between a ligand and target molecule is atypical in biological systems. In contrast to the definition of ligand in metalorganic and inorganic chemistry, in biochemistry it is ambiguous whether the ligand generally binds at a metal site, as is the case in hemoglobin. In general, the interpretation of ligand is contextual with regards to what sort of binding has been observed.
Ligand binding to a receptor protein alters the conformation by affecting the three-dimensional shape orientation. The conformation of a receptor protein composes the functional state. Ligands include substrates, inhibitors, activators, s
|
https://en.wikipedia.org/wiki/Alastair%20Fitter
|
Alastair Hugh Fitter CBE FRS (born 20 June 1948) is a British ecologist at the University of York.
Fitter was educated at Oxford and at Liverpool, and came to the Department of Biology in York in 1972. In 2004 he was appointed Pro-Vice-Chancellor, with the Research portfolio. He is a member of Council of the Natural Environment Research Council.
Fitter's research interests include plant and microbial behaviour in a changing world; functional ecology of roots and mycorrhizal associations under field conditions; root system architecture; carbon cycling in soil, especially in relation to mycorrhizas; phenological responses to climate change.
Alastair Fitter is the son of the naturalist and author Richard Fitter (1913–2005), and together in 2002 they published an article in Science on the changing phenology of wild flowers due to global warming. They have also collaborated on numerous field guides and other natural history books.
Fitter was elected Fellow of the Royal Society (FRS) in 2005. He was appointed Commander of the Order of the British Empire (CBE) in the 2010 New Year Honours for services to environmental science. He received a President's Medal from the British Ecological Society.
References
External links
Alastair Fitter home page
1948 births
Living people
Place of birth missing (living people)
Alumni of the University of Oxford
Alumni of the University of Liverpool
Academics of the University of York
British nature writers
English botanists
New Naturalist w
|
https://en.wikipedia.org/wiki/Plume
|
Plume or plumes may refer to:
Science
Plume (feather), a prominent bird feather
Plume (fluid dynamics), a column consisting of one fluid moving through another fluid
Eruption plume, a column of volcanic ash and gas emitted into the atmosphere during an eruption
Mantle plume, an upwelling of hot rock within the Earth's mantle that can cause volcanic hotspots
Moisture plume, an alternative name for an atmospheric river, a narrow corridor of concentrated moisture in the atmosphere
Plumage, the layer of feathers that cover a bird
Media and literature
"Plume" (Air episode), a 2005 episode of the Japanese anime Air
Plume, a 2006 album by Loscil
Plumes (play), a 1927 one-act play by Georgia Douglas Johnson
Plume (poetry collection), a 2012 book by Kathleen Flenniken
Plume (publisher), an American book publishing company
Plumes, a 1924 novel by Laurence Stallings
A song by The Smashing Pumpkins on their 1994 album Pisces Iscariot
"Plume", a song by Caravan Palace on the 2019 album Chronologic
People
Plume Latraverse (born 1946), Canadian singer, musician, and writer
Amélie Plume (born 1943), Swiss writer
Helen Plume, New Zealand climate change expert
Ilse Plume, American children's book illustrator
Kenneth Plume (born 1977), American author and broadcaster
Mike Plume (born 1968), Canadian country music singer and songwriter
Roberts Plūme (1897–1956), Latvian cyclist and cross-country skier
Thomas Plume (1630–1704), English churchman and philanthropist, foun
|
https://en.wikipedia.org/wiki/Madison%20Symmetric%20Torus
|
The Madison Symmetric Torus (MST) is a reversed field pinch (RFP) physics experiment with applications to both fusion energy research and astrophysical plasmas.
MST is located at the Center for Magnetic Self Organization (CMSO) at the University of Wisconsin-Madison.
RFPs are significantly different from tokamaks (the most popular magnetic confinement scheme) in that they tend to have a higher power density and better confinement characteristics for a given average magnetic field. RFPs also tend to be dominated by non-ideal phenomena and turbulent effects.
Classification
As in most such experiments, the MST plasma is a toroidal pinch, which means the plasma is shaped like a donut and confined by a magnetic field generated by a large current flowing through it. MST falls into an unconventional class of machine called a reversed field pinch (RFP.) The RFP is so named because the toroidal magnetic field that permeates the plasma spontaneously reverses direction near the edge.
A reversed field pinch is formed similarly to other toroidal pinch devices, by driving current through the plasma from an associated capacitor bank or other high-current power sources. In a tokamak the toroidal field is much stronger than the poloidal field, but in an RFP it's just the opposite. In fact, in an RFP the externally applied toroidal field is switched off shortly after startup.
The plasma in an RFP is also much closer to the wall than in a Tokamak. This permits a peculiar arrangement of th
|
https://en.wikipedia.org/wiki/Futures%20and%20promises
|
In computer science, future, promise, delay, and deferred refer to constructs used for synchronizing program execution in some concurrent programming languages. They describe an object that acts as a proxy for a result that is initially unknown, usually because the computation of its value is not yet complete.
The term promise was proposed in 1976 by Daniel P. Friedman and David Wise,
and Peter Hibbard called it eventual.
A somewhat similar concept future was introduced in 1977 in a paper by Henry Baker and Carl Hewitt.
The terms future, promise, delay, and deferred are often used interchangeably, although some differences in usage between future and promise are treated below. Specifically, when usage is distinguished, a future is a read-only placeholder view of a variable, while a promise is a writable, single assignment container which sets the value of the future. Notably, a future may be defined without specifying which specific promise will set its value, and different possible promises may set the value of a given future, though this can be done only once for a given future. In other cases a future and a promise are created together and associated with each other: the future is the value, the promise is the function that sets the value – essentially the return value (future) of an asynchronous function (promise). Setting the value of a future is also called resolving, fulfilling, or binding it.
Applications
Futures and promises originated in functional programming an
|
https://en.wikipedia.org/wiki/Harold%20Johnson%20%28astronomer%29
|
Harold Lester Johnson (April 17, 1921 – April 2, 1980) was an American astronomer.
Harold Johnson was born in Denver, Colorado, on April 17, 1921. He received his early education in Denver public schools and went to the University of Denver, graduating with a degree in mathematics in 1942. Johnson was recruited by the MIT Radiation Laboratory to work on World War II related radar research. After the war Johnson began graduate studies in astronomy at University of California, Berkeley where he completed his thesis under Harold Weaver in 1948.
In the following years working at Lowell Observatory, University of Wisconsin–Madison, Yerkes Observatory (where he met William Wilson Morgan), McDonald Observatory, University of Texas–Austin, the Lunar and Planetary Laboratory in Tucson, Arizona, and the National Autonomous University of Mexico he applied his instrumental and electronic talents to developing and calibrating astronomical photoelectric detectors.
He died of a heart attack in Mexico City in 1980. He and his wife, Mary Elizabeth Jones, had two children.
Johnson was awarded the Helen B. Warner Prize by the American Astronomical Society in 1956. He was elected to the National Academy of Sciences in 1969. He is remembered for introducing the UBV photometric system (also called the Johnson or Johnson-Morgan system), along with William Wilson Morgan in 1953.
External links
National Academy of Sciences Biography by Gérard Henri de Vaucouleurs
1921 births
1980 deaths
20t
|
https://en.wikipedia.org/wiki/Amplified%20fragment%20length%20polymorphism
|
AFLP-PCR or just AFLP is a PCR-based tool used in genetics research, DNA fingerprinting, and in the practice of genetic engineering. Developed in the early 1990s by KeyGene, AFLP uses restriction enzymes to digest genomic DNA, followed by ligation of adaptors to the sticky ends of the restriction fragments. A subset of the restriction fragments is then selected to be amplified. This selection is achieved by using primers complementary to the adaptor sequence, the restriction site sequence and a few nucleotides inside the restriction site fragments (as described in detail below). The amplified fragments are separated and visualized on denaturing on agarose gel electrophoresis, either through autoradiography or fluorescence methodologies, or via automated capillary sequencing instruments.
Although AFLP should not be used as an acronym, it is commonly referred to as "Amplified fragment length polymorphism". However, the resulting data are not scored as length polymorphisms, but instead as presence-absence polymorphisms.
AFLP-PCR is a highly sensitive method for detecting polymorphisms in DNA. The technique was originally described by Vos and Zabeau in 1993. In detail, the procedure of this technique is divided into three steps:
Digestion of total cellular DNA with one or more restriction enzymes and ligation of restriction half-site specific adaptors to all restriction fragments.
Selective amplification of some of these fragments with two PCR primers that have corresponding a
|
https://en.wikipedia.org/wiki/AFLP
|
AFLP may refer to:
Amplified fragment length polymorphism, a highly sensitive tool used in molecular biology to detect DNA polymorphisms
Acute fatty liver of pregnancy, a life-threatening liver condition that may occur during pregnancy
|
https://en.wikipedia.org/wiki/George%20R.%20Riddle
|
George Read Riddle (1817 – March 28, 1867) was an American engineer, lawyer and politician from Wilmington, Delaware. He was a member of the Democratic Party who served as U.S. Representative and as U.S. Senator from Delaware.
Early life and family
Riddle was born in New Castle, Delaware, and studied civil engineering at Delaware College, now the University of Delaware. In addition he studied law and was admitted to the Delaware Bar in 1848, beginning a practice in Wilmington, Delaware. With his engineering background, he was named as a commissioner to retrace the Mason–Dixon line in 1849, and was otherwise engaged in the construction of railroads and canals. In 1844, Riddle was hired to design the Wilmington and Brandywine Cemetery. During the Civil War, Riddle served with the Home Guard of Wilmington. His wife's name was Margaret.
Political career
From 1849 to 1850, Riddle served as a Deputy Attorney General of the United States. After losing in the election of 1844, he was elected to the U.S. House in 1850 and served for two terms from March 4, 1851, until March 3, 1855. During the 33rd Congress, Riddle was the Chairman of the Committee on Engraving. Running for a third term he was defeated in 1854 by Elisha D. Cullen.
In 1860, Riddle was one of only two slaveholders in Delaware. He owned three slaves, a 68-year-old male and two females aged 56 and 12.
On February 2, 1864, Riddle was elected to the United States Senate to fill the vacancy caused by the resignation of
|
https://en.wikipedia.org/wiki/Renninger%20negative-result%20experiment
|
In quantum mechanics, the Renninger negative-result experiment is a thought experiment that illustrates some of the difficulties of understanding the nature of wave function collapse and measurement in quantum mechanics. The statement is that a particle need not be detected in order for a quantum measurement to occur, and that the lack of a particle detection can also constitute a measurement. The thought experiment was first posed in 1953 by Mauritius Renninger. The non-detection of a particle in one arm of an interferometer implies that the particle must be in the other arm. It can be understood to be a refinement of the paradox presented in the Mott problem.
The Mott problem
The Mott problem concerns the paradox of reconciling the spherical wave function describing the emission of an alpha ray by a radioactive nucleus, with the linear tracks seen in a cloud chamber. Formulated in 1929 by Sir Nevill Francis Mott and Werner Heisenberg, it was resolved by a calculation done by Mott that showed that the correct quantum mechanical system must include the wave functions for the atoms in the cloud chamber as well as that for the alpha ray. The calculation showed that the resulting probability is non-zero only on straight lines raying out from the decayed atom; that is, once the measurement is performed, the wave-function becomes non-vanishing only near the classical trajectory of a particle.
Renninger's negative-result experiment
In Renninger's 1960 formulation, the cloud c
|
https://en.wikipedia.org/wiki/Intervalence%20charge%20transfer
|
In chemistry, intervalence charge transfer, often abbreviated IVCT or even IT, is a type of charge-transfer band that is associated with mixed valence compounds. It is most common for systems with two metal sites differing only in oxidation state. Quite often such electron transfer reverses the oxidation states of the sites. The term is frequently extended to the case of metal-to-metal charge transfer between non-equivalent metal centres. The transition produces a characteristically intense absorption in the electromagnetic spectrum. The band is usually found in the visible or near infrared region of the spectrum and is broad.
The process can be described as follows:
LnM+-bridge-M'Ln + hν → LnM-bridge-M'+Ln
where L is a bridging ligand.
Mixed valency and the IT band
Since the energy states of valence tautomers affect the IVCT band, the strength of electronic interaction between the sites, known as α (the mixing coefficient), can be determined by analysis of the IVCT band. Depending on the value of α, mixed valence complexes are classified into three groups:
class I: α ~ 0, the complex has no interaction between redox sites. No IVCT band is observed. The oxidation states of the two metal sites are distinct and do not readily interconvert.
class II: 0 < α < = 0.707, intermediate interaction between sites. An IVCT band is observed. The oxidation states of the two metal sites are distinct, but they readily interconvert. This is by far the most common class of interva
|
https://en.wikipedia.org/wiki/Explicit%20formulae%20for%20L-functions
|
In mathematics, the explicit formulae for L-functions are relations between sums over the complex number zeroes of an L-function and sums over prime powers, introduced by for the Riemann zeta function. Such explicit formulae have been applied also to questions on bounding the discriminant of an algebraic number field, and the conductor of a number field.
Riemann's explicit formula
In his 1859 paper "On the Number of Primes Less Than a Given Magnitude" Riemann sketched an explicit formula (it was not fully proven until 1895 by von Mangoldt, see below) for the normalized prime-counting function which is related to the prime-counting function by
which takes the arithmetic mean of the limit from the left and the limit from the right at discontinuities. His formula was given in terms of the related function
in which a prime power counts as of a prime. The normalized prime-counting function can be recovered from this function by
where is the Möbius function. Riemann's formula is then
involving a sum over the non-trivial zeros of the Riemann zeta function. The sum is not absolutely convergent, but may be evaluated by taking the zeros in order of the absolute value of their imaginary part. The function occurring in the first term is the (unoffset) logarithmic integral function given by the Cauchy principal value of the divergent integral
The terms involving the zeros of the zeta function need some care in their definition as has branch points at 0 and 1, and are d
|
https://en.wikipedia.org/wiki/Balfour%20Stewart
|
Balfour Stewart (1 November 182819 December 1887) was a Scottish physicist and meteorologist.
His studies in the field of radiant heat led to him receiving the Rumford Medal of the Royal Society in 1868. In 1859 he was appointed director of Kew Observatory. He was elected professor of physics at Owens College, Manchester, and retained that chair until his death, which happened near Drogheda, in Ireland, on 19 December 1887. He was the author of several successful science textbooks, and also of the article on "Terrestrial Magnetism" in the ninth edition of the Encyclopædia Britannica.
Career
Stewart was born on 1 November 1828 at 1 London Row in Leith (north of Edinburgh), the son of William Stewart a tea merchant, and his wife, Jane Clouston. His father was involved in business in Great Britain and Australia.
He was educated at Dundee. He then studied Physics at the University of St Andrews, and the University of Edinburgh. Following his studies of physics at Edinburgh, he became assistant to James David Forbes in 1856. Forbes was especially interested in questions of heat, meteorology, and terrestrial magnetism, and it was to these that Stewart also mainly devoted himself.
Radiant heat first claimed his attention, and by 1858 he had completed his first investigations into the subject. These yielded a remarkable extension of Pierre Prévost's "Law of Exchanges," and enabled him to establish the fact that radiation is not a surface phenomenon, but takes place throughout the
|
https://en.wikipedia.org/wiki/Melvin%20Schwartz
|
Melvin Schwartz (; November 2, 1932 – August 28, 2006) was an American physicist. He shared the 1988 Nobel Prize in Physics with Leon M. Lederman and Jack Steinberger for their development of the neutrino beam method and their demonstration of the doublet structure of the leptons through the discovery of the muon neutrino.
Biography
He was Jewish. He grew up in New York City in the Great Depression and went to the Bronx High School of Science. His interest in physics began there at the age of 12.
He earned his B.A. (1953) and Ph.D. (1958) at Columbia University, where Nobel laureate Isidor Isaac Rabi was the head of the physics department. Schwartz became an assistant professor at Columbia in 1958. He was promoted to associate professor in 1960 and full professor in 1963. Tsung-Dao Lee, a Columbia colleague who had recently won the Nobel prize at age 30, inspired the experiment for which Schwartz received his Nobel. Schwartz and his colleagues performed the experiments which led to their Nobel Prize in the early 1960s, when all three were on the Columbia faculty. The experiment was carried out at the nearby Brookhaven National Laboratory.
In 1966, after 17 years at Columbia, he moved west to Stanford University, where SLAC, a new accelerator, was just being completed. There, he was involved in research investigating the charge asymmetry in the decay of long-lived neutral kaons and another project which produced and detected relativistic hydrogen-like atoms made up of
|
https://en.wikipedia.org/wiki/Henry%20Way%20Kendall
|
Henry Way Kendall (December 9, 1926 – February 15, 1999) was an American particle physicist who won the Nobel Prize in Physics in 1990 jointly with Jerome Isaac Friedman and Richard E. Taylor "for their pioneering investigations concerning deep inelastic scattering of electrons on protons and bound neutrons, which have been of essential importance for the development of the quark model in particle physics."
Biography
Kendall was born in Boston to Evelyn Way and Henry P. Kendall, an industrialist. Kendall grew up in Sharon, Massachusetts and attended Deerfield Academy. He enrolled in the U. S. Merchant Marine Academy in 1945, and served on a troop transport on the North Atlantic in the winter of 1945 – 1946.
In 1946, he enrolled at Amherst College where he majored in mathematics, graduating in 1950. While at Amherst, he operated a diving and marine salvage company during two summers. He co-authored two books, one on shallow water diving and the other on underwater photography.
He did graduate research at the Massachusetts Institute of Technology, involving an experimental study of positronium, and he obtained his PhD in 1955. He then spent the next two years as a postdoctoral fellow at Brookhaven National Laboratory. He then spent five years in Robert Hofstadter's research group at Stanford University in the late 1950s and early 1960s, where he worked with Jerome Friedman and Richard Taylor, studying the structure of protons and neutrons, using the university's 300 feet
|
https://en.wikipedia.org/wiki/Robert%20Coleman%20Richardson
|
Robert Coleman Richardson (June 26, 1937 – February 19, 2013) was an American experimental physicist whose area of research included sub-millikelvin temperature studies of helium-3. Richardson, along with David Lee, as senior researchers, and then graduate student Douglas Osheroff, shared the 1996 Nobel Prize in Physics for their 1972 discovery of the property of superfluidity in helium-3 atoms in the Cornell University Laboratory of Atomic and Solid State Physics.
Richardson was born in Washington D.C. He went to high school at Washington-Lee in Arlington, Virginia. He later described Washington-Lee's biology and physics courses as "very old-fashioned" for the time. "The idea of 'advanced placement' had not yet been invented," he wrote in his Nobel Prize autobiography. He took his first calculus course when he was a sophomore in college.
Richardson attended Virginia Tech and received a B.S. in 1958 and a M.S. in 1960. He received his PhD from Duke University in 1965.
Background
At the time of his death, he was the Floyd Newman Professor of Physics at Cornell University, although he no longer operated a laboratory. From 1998 to 2007 he served as Cornell's vice provost for research, and from 2007 to 2009 was senior science adviser to the president and provost. His past experimental work focused on using Nuclear Magnetic Resonance to study the quantum properties of liquids and solids at extremely low temperatures.
Richardson was an Eagle Scout, and mentioned the Scouting ac
|
https://en.wikipedia.org/wiki/History%20of%20fluid%20mechanics
|
The history of fluid mechanics is a fundamental strand of the history of physics and engineering. The study of the movement of fluids (liquids and gases) and the forces that act upon them dates back to pre-history. The field has undergone a continuous evolution, driven by human dependence on water, meteorological conditions and internal biological processes.
The success of early civilizations, can be attributed to developments in the understanding of water dynamics, allowing for the construction of canals and aqueducts for water distribution and farm irrigation, as well as maritime transport. Due to its conceptual complexity, most discoveries in this field relied almost entirely on experiments, at least until the development of advanced understanding of differential equations and computational methods. Significant theoretical contributions were made by notables figures like Archimedes, Johann Bernoulli, Leonhard Euler, Claude-Louis Navier and Stokes, who developed the fundamental equations to describe fluid mechanics. Advancements in experimentation and computational methods have further propelled the field, leading to practical applications in more specialized industries ranging from aerospace to environmental engineering. Fluid mechanics has also been important for the study astronomical bodies and the dynamics of galaxies.
Antiquity
Pre-history
A pragmatic, if not scientific, knowledge of fluid flow was exhibited by ancient civilizations, such as in the design of arro
|
https://en.wikipedia.org/wiki/Surface%20power%20density
|
In physics and engineering, surface power density is power per unit area.
Applications
The intensity of electromagnetic radiation can be expressed in W/m2. An example of such a quantity is the solar constant.
Wind turbines are often compared using a specific power measuring watts per square meter of turbine disk area, which is , where r is the length of a blade. This measure is also commonly used for solar panels, at least for typical applications.
Radiance is surface power density per unit of solid angle (steradians) in a specific direction. Spectral radiance is radiance per unit of frequency (Hertz) at a specific frequency.
Surface power densities of energy sources
Surface power density is an important factor in comparison of industrial energy sources. The concept was popularised by geographer Vaclav Smil. The term is usually shortened to "power density" in the relevant literature, which can lead to confusion with homonymous or related terms.
Measured in W/m2 it describes the amount of power obtained per unit of Earth surface area used by a specific energy system, including all supporting infrastructure, manufacturing, mining of fuel (if applicable) and decommissioning., Fossil fuels and nuclear power are characterized by high power density which means large power can be drawn from power plants occupying relatively small area. Renewable energy sources have power density at least three orders of magnitude smaller and for the same energy output they need to occupy acc
|
https://en.wikipedia.org/wiki/Jo%C3%A3o%20Magueijo
|
João Magueijo (born 1967) is a Portuguese cosmologist and professor in theoretical physics at Imperial College London. He is a pioneer of the varying speed of light (VSL) theory.
Education and career
João Magueijo studied physics at the University of Lisbon. He undertook graduate work and Ph.D. at Cambridge University. He was awarded a research fellowship at St John's College, Cambridge. He has been a faculty member at Princeton and Cambridge and is currently a professor at Imperial College London where he teaches undergraduates General Relativity and postgraduates Advanced General Relativity.
In 1998, Magueijo teamed with Andreas Albrecht to work on the varying speed of light (VSL) theory of cosmology, which proposes that the speed of light was up to in the early universe. This would explain the horizon problem (since distant regions of the expanding universe would have had time to interact and homogenize their properties) and is presented as an alternative to the more mainstream theory of cosmic inflation.
Magueijo discusses his personal struggles pursuing VSL in his 2003 book, Faster Than The Speed of Light, The Story of a Scientific Speculation. He was associated with a misunderstanding over priority concerning VSL with John Moffat. He was also the host of the Science Channel special João Magueijo's Big Bang, which premiered on 13 May 2008.
In 2009, he published A Brilliant Darkness, an account of the life and science of vanished physicist Ettore Majorana.
In 2014,
|
https://en.wikipedia.org/wiki/Neurophilosophy
|
Neurophilosophy or philosophy of neuroscience is the interdisciplinary study of neuroscience and philosophy that explores the relevance of neuroscientific studies to the arguments traditionally categorized as philosophy of mind. The philosophy of neuroscience attempts to clarify neuroscientific methods and results using the conceptual rigor and methods of philosophy of science.
Specific issues
Below is a list of specific issues important to philosophy of neuroscience:
"The indirectness of studies of mind and brain"
"Computational or representational analysis of brain processing"
"Relations between psychological and neuroscientific inquiries"
Modularity of mind
What constitutes adequate explanation in neuroscience?
"Location of cognitive function"
The indirectness of studies of mind and brain
Many of the methods and techniques central to neuroscientific discovery rely on assumptions that can limit the interpretation of the data. Philosophers of neuroscience have discussed such assumptions in the use of functional magnetic resonance imaging, dissociation in cognitive neuropsychology, single unit recording, and computational neuroscience. Following are descriptions of many of the current controversies and debates about the methods employed in neuroscience.
fMRI
Many fMRI studies rely heavily on the assumption of "localization of function" (same as functional specialization).
Localization of function means that many cognitive functions can be localized to specific brai
|
https://en.wikipedia.org/wiki/Macro-engineering
|
In engineering, macro-engineering (alternatively known as mega engineering) is the implementation of large-scale design projects. It can be seen as a branch of civil engineering or structural engineering applied on a large landmass. In particular, macro-engineering is the process of marshaling and managing of resources and technology on a large scale to carry out complex tasks that last over a long period. In contrast to conventional engineering projects, macro-engineering projects (called macro-projects or mega-projects) are multidisciplinary, involving collaboration from all fields of study. Because of the size of macro-projects they are usually international.
Macro-engineering is an evolving field that has only recently started to receive attention. Because we routinely deal with challenges that are multinational in scope, such as global warming and pollution, macro-engineering is emerging as a transcendent solution to worldwide problems.
Macro-engineering is distinct from Megascale engineering due to the scales where they are applied. Where macro-engineering is currently practical, mega-scale engineering is still within the domain of speculative fiction because it deals with projects on a planetary or stellar scale.
Projects
Macro engineering examples include the construction of the Panama Canal and the Suez Canal.
Planned projects
Examples of projects include the Channel Tunnel and the planned Gibraltar Tunnel.
Two intellectual centers focused on macro-engineering
|
https://en.wikipedia.org/wiki/Dries%20Buytaert
|
Dries Buytaert (born 19 November 1978) is a Belgian open-source software programmer. He is the founder and lead developer of the Drupal content management system. He also serves as the CTO of Acquia.
Career
Buytaert was born in Wilrijk, Antwerp, Belgium. He defended his PhD dissertation in computer science on 27 January 2008, at Ghent University in Belgium.
From 1999 to 2000 he was the maintainer of the Linux-WLAN FAQ.
On 1 December 2007, Dries announced, together with co-founder Jay Batson, the launch of a start-up called Acquia. Acquia is a commercial open-source software company providing products, services, and technical support for Drupal. Acquia tries to be to Drupal what Red Hat has been to Linux. In 2009, Acquia helped re-launch Whitehouse.gov on Drupal.
On 31 March 2008, Dries launched Mollom, a service dedicated to stopping website spam: "Mollom's purpose is to dramatically reduce the effort of keeping your site clean and the quality of your content high. Currently, Mollom is a spam-killing one-two punch combination of a state-of-the-art spam filter and CAPTCHA server." Over 59,000 websites are protected by the Mollom service, including all of Netlog's messages. Mollom support ended 2 April 2018.
In 2008, Buytaert was elected "Young Entrepreneurs of Tech" by BusinessWeek. He was also named to the MIT Technology Review TR35 as one of the top 35 innovators in the world under the age of 35.
Dismissal of Larry Garfield
In March of 2017, Buytaert fired Drupal deve
|
https://en.wikipedia.org/wiki/Vernon%20Ingram
|
Vernon Martin Ingram, (May 19, 1924 – August 17, 2006) was a German–American professor of biology at the Massachusetts Institute of Technology.
Biography
Ingram was born in Breslau as Werner Adolf Martin Immerwahr, Lower Silesia. When he was 14, he and his family left Nazi Germany because of their opposition to Nazism (being Jewish) and settled in England. He then Anglicised his name to Vernon Ingram.
During the Second World War, Ingram worked at a chemical factory producing drugs for the war effort and at night studied at Birkbeck College at the University of London. He received a bachelor's degree in chemistry in 1945 and a PhD in organic chemistry in 1949.
After receiving his doctorate, Ingram worked at postdoctoral appointments at the Rockefeller Institute and Yale University. At Rockefeller, he worked with Moses Kunitz on crystallising proteins. While at Yale, he studied peptide chemistry with Joseph Fruton. In 1952, Ingram returned to England and started working at the Cavendish Laboratory at the University of Cambridge, studying protein chemistry.
In 1956, Ingram, John A. Hunt, and Antony O. W. Stretton determined that the change in the haemoglobin molecule in sickle cell disease and trait was the substitution of the glutamic acid in position 6 of the β-chain of the normal protein by valine. Ingram used electrophoresis and chromatography to show that the amino acid sequence of normal human and sickle cell anaemia haemoglobins differed due to a single substitu
|
https://en.wikipedia.org/wiki/Cognitive%20revolution
|
The cognitive revolution was an intellectual movement that began in the 1950s as an interdisciplinary study of the mind and its processes. It later became known collectively as cognitive science. The relevant areas of interchange were between the fields of psychology, linguistics, computer science, anthropology, neuroscience, and philosophy. The approaches used were developed within the then-nascent fields of artificial intelligence, computer science, and neuroscience. In the 1960s, the Harvard Center for Cognitive Studies and the Center for Human Information Processing at the University of California, San Diego were influential in developing the academic study of cognitive science. By the early 1970s, the cognitive movement had surpassed behaviorism as a psychological paradigm. Furthermore, by the early 1980s the cognitive approach had become the dominant line of research inquiry across most branches in the field of psychology.
A key goal of early cognitive psychology was to apply the scientific method to the study of human cognition. Some of the main ideas and developments from the cognitive revolution were the use of the scientific method in cognitive science research, the necessity of mental systems to process sensory input, the innateness of these systems, and the modularity of the mind. Important publications in triggering the cognitive revolution include psychologist George Miller's 1956 article "The Magical Number Seven, Plus or Minus Two" (one of the most frequently
|
https://en.wikipedia.org/wiki/Hot%20atom
|
In physical chemistry, a hot atom is an atom that has a high kinetic or internal energy.
When molecule AB adsorbs on a surface dissociatively,
both A and B adsorb on the surface, or
only A adsorbs on the surface, and B desorbs from the surface.
In case 2, B gains a high translational energy from the adsorption energy of A, and hot atom B is generated. For example, the hydrogen molecule, because of its light mass, gets a high translational energy. Such a hot atom does not fly into vacuum but is trapped on the surface, where it diffuses with high energy.
Hot atoms are expected to play important roles in catalytic reactions. For example, a reaction of a hydrogen atom with hydrogen atoms on a silicon surface and a reaction of an oxygen atom with oxygen molecules on Pt(111) have been reported. Hot atoms can also be generated by degenerating molecules on a metal surface with UV light. It has been reported that the reactivity of an oxygen atom generated in such a way on a platinum surface is different from that of chemisorbed oxygen atoms. Elucidating the role of hot atoms on surfaces will lead to a deeper understanding of the mechanism of reactions.
References
See also
Nonthermal surface reaction
Physical chemistry
|
https://en.wikipedia.org/wiki/M%26E
|
M&E may refer to:
Morris and Essex Railroad
Morris & Essex Lines
Morristown and Erie Railway
Monitoring and Evaluation
Electromechanics, combines mechanical engineering and electrical engineering
Mechatronics, a portmanteau of mechanics and electronics
Machinery and Equipment (accounting)
Meals and Entertainment (accounting)
|
https://en.wikipedia.org/wiki/Pusher%20trailer
|
A pusher trailer is a device attached to the rear of a vehicle or bike that provides force to assist the vehicle.
For bikes
Electric
Electric pusher trailers use energy stored in a battery, typically of lithium ion or sealed lead acid chemistry, to provide power. Two wheel and one wheel designs are common.
Gas
Gas powered pusher trailers typically employ a two or four stroke internal combustion engine to provide power.
For cars
Pusher trailers are gasoline, diesel or electric fueled trailers with a traditional internal combustion engine (petroleum engines) and transmission which can be hitched up to battery electric vehicles and run from the cockpit to give the vehicle increased range.
The trailer provides ground traction through the wheels to push the trailer forward, and by default, the electric vehicle as well. In this way, a trip beyond the normal range of the EV can be undertaken without stopping for recharging.
Some types of articulated bus have the engine (and propulsion) in the rear section.
See also
Bicycle trailer
Genset trailer
Trailer (vehicle)
References
External links
http://www.evalbum.com/pushers.html
https://web.archive.org/web/20010203125300/http://jstraubel.com/EVpusher/EVpusher.htm
http://www.housetrucks.org/pusher.htm
Electric vehicles
|
https://en.wikipedia.org/wiki/Eldar%20Djangirov
|
Eldar Djangirov (born January 28, 1987), also known as Eldar, is an American jazz pianist. He was born in Bishkek, Kyrgyz SSR, Soviet Union to Tatiana, a piano teacher, and Emil, a professor of mechanical engineering, and is of Volga Tatar and Russian descent. He grew up in Kansas City, MO from the age of 10 and also lived in San Diego, California during his teenage years. As of 2007, he resides in New York City.
Career
Eldar began playing the piano when he was three years old. The first piece he remembers learning was "C Jam Blues". He later took classical lessons and was "discovered" at age 9 by the late New York City jazz aficionado Charles McWhorter, who saw him play at a festival in Siberia. The family relocated to Kansas City, drawn there in large part by the city's jazz history. During his Kansas City years, even before reaching his teens, Eldar already started building a reputation as a child prodigy, appearing on Marian McPartland's NPR show, Piano Jazz, when he was only 12 years old, being the youngest performer to appear on her show. Eldar attended Interlochen Center for the Arts in his young teenage years. Eldar attended St. Elizabeth's grade school and the Barstow School in Kansas City. Eventually, the family moved to San Diego where he attended the Francis W. Parker School (San Diego), and then to the Los Angeles area where he attended University of Southern California's Thornton School of Music. Eldar's playing style is characterized by prodigious technique an
|
https://en.wikipedia.org/wiki/R.%20J.%20Berry
|
Robert James "Sam" Berry (26 October 1934 – 29 March 2018) was a British geneticist, naturalist and Christian theorist. He was professor of genetics at University College London between 1974 and 2000. Before that he was a lecturer in genetics at The Royal Free Hospital School of Medicine in London. He was president from 1983 to 1986 of the Linnean Society, the British Ecological Society and the European Ecological Federation. As a Christian, Berry spoke out in favour of theistic evolution, served as a lay member of the Church of England's General Synod and as president of Christians in Science. He was a member of the Board of Governors of Monkton Combe School from 1979 to 1991. He gave the 1997–98 Glasgow Gifford Lectures entitled Gods, Genes, Greens and Everything. His father, A. J. Berry, died in 1947.
Early life and education
He was educated at Kirkham Grammar School and Shrewsbury School. One of his first published works in 1961 was in the "Teach yourself books" series Genetics. The paperback version was released in 1972.
Bibliography
Biological works
Teach yourself books Genetics. (1965)
Inheritance and Natural History. New Naturalist series no. 61 (1977)
The Natural History of Shetland. New Naturalist series no. 64 (1980)
The Natural History of Orkney. New Naturalist series no. 70 (1985)
Genes in Ecology (ed. R. J. Berry, T. J. Crawford, G. M. Hewitt, N. R. Webb) (1992)
Islands. New Naturalist series no. 109 (2009)
Religious works
God and the Biologis
|
https://en.wikipedia.org/wiki/Steve%20Lombardi
|
Steven Kenneth Lombardi (born April 18, 1961) is an American professional wrestler and road agent, better known by his ring name, the Brooklyn Brawler. He is best known for his tenure in WWE, as well as several independent promotions.
Early life
Lombardi studied biochemistry at St. Francis College prior to his wrestling career.
Professional wrestling career
World Wrestling Federation / WWE (1983–2016)
Early career (1983–1989)
Lombardi began his WWF career in late 1983, competing under his real name, and being a heel, primarily as an enhancement talent. His debut came on July 15, 1983, in Queens, NY where he was defeated by Swede Hanson. After facing Ivan Koloff and Sgt. Slaughter on house show matches, Lombardi made his TV debut on the October 29 episode of All American Wrestling where he was submitted by The Iron Sheik and carried out on a stretcher. He then began regular appearances on both television and house shows.
After losing numerous matches that winter, Lombardi gained his first success on March 18, 1984, when he wrestled Jerry Valiant to a draw. Another draw, this time with Terry Daniels came on April 24 in Mountaintop, PA. But apart from that he continued on as an enhancement talent, losing to much of the WWF roster including Big John Studd, Paul Orndorff, David Schultz, Iron Mike Sharpe, Rocky Johnson, and others. In the midst of another long losing streak, Lombardi then gained a second draw against Daniels on June 1 in Winston-Salem, NC. He made his Madiso
|
https://en.wikipedia.org/wiki/Johann%20Gottlieb%20N%C3%B6rremberg
|
Johann Gottlieb Christian Nörremberg (11 August 1787, in Pustenbach – 20 July 1862) was a German physicist who worked on the polarization of light.
From 1823 he taught classes in mathematics and physics at the military school in Darmstadt. In 1833 he became a professor of mathematics, physics and astronomy at the University of Tübingen, where he worked on surveying and the development of optical instruments. Among his better known creations was a polarization apparatus, a device used in the making of a "Nörremberg polariscope". Most of his scientific articles were published in Poggendorfs Annalen.
Notes
External links
1787 births
1862 deaths
19th-century German physicists
Academic staff of the University of Tübingen
People from Bergneustadt
|
https://en.wikipedia.org/wiki/Harry%20Steenbock
|
Harry Steenbock (August 16, 1886, Charlestown, Wisconsin – December 25, 1967, Madison, Wisconsin) was a professor of biochemistry at the University of Wisconsin–Madison. Steenbock graduated from Wisconsin in 1916, where he was a member of Phi Sigma Kappa fraternity.
Vitamin D
Steenbock was born in Charlestown, Wisconsin, and grew up on a model farm outside New Holstein, Wisconsin. His graduate advisor at the University of Wisconsin–Madison, was Edwin B. Hart. His first publication reported the results of the single-grain experiment on which he assisted with Hart and Stephen Moulton Babcock. During his graduate career, Steenbock also served as an assistant in the lab of Elmer McCollum. When McCollum and another assistant Marguerite Davis published their discovery of what came to be called vitamin A, Steenbock thought he deserved more credit than he received. Steenbock carried on the vitamin A work in Madison, after McCollum accepted an offer from Johns Hopkins University.
In 1923, Steenbock demonstrated that irradiation by ultraviolet light increased the vitamin D content of foods and other organic materials. After irradiating rodent food, Steenbock discovered that the rodents were cured of rickets. It is now known that vitamin D deficiency is a cause of rickets.
Using $300 of his own money, Steenbock patented his invention. Steenbock's irradiation technique was used for food stuffs, but most memorably for milk. By the expiration of the patent in 1945, rickets had all but
|
https://en.wikipedia.org/wiki/Derek%20Burney%20Jr.
|
Derek Burney is the former president of Corel Corporation.
In 1988, at the age of 26, Burney entered the Computer Science program at Carleton University, spending co-op terms at Nortel and Atomic Energy of Canada Limited (AECL). He began his career with Corel as a developer and, with the help of his mentor Michael Cowpland, rose quickly through the ranks, eventually heading the engineering department and becoming President and Chief executive officer following Cowpland's resignation in 2000.
After taking the company private with Vector Capital, Burney held the position of Chairman until he resigned to join Microsoft in 2004.
Burney is currently corporate vice president of Customer Technical Engagement in Microsoft's Worldwide Commercial Business.
Burney's father, Derek Burney Sr., is a noted Canadian businessperson and diplomat.
References
External links
Carleton University alumni profile from 2001
Canadian businesspeople
Carleton University alumni
Year of birth missing (living people)
Living people
Corel
Nortel people
|
https://en.wikipedia.org/wiki/Robert%20Pashley
|
Robert Pashley (4 September 1805 – 29 May 1859) was a 19th-century English traveller, lawyer and economist.
Pashley was born in York and he studied at Trinity College, Cambridge. Distinguished in mathematics and Classics, in 1830 he was elected a Fellow of Trinity at his first sitting. In 1832 he took his MA degree, and as a travelling Fellow undertook a journey in Italy, Greece, Asia Minor and Crete, of which he published his two-volume Travels in Crete. His work is considered a classic of writing on the Ottoman Empire, with his detailed observations on local geography, customs, and social issues.
In 1837, he was called to the Bar by the Inner Temple. He lost his valuable library and antiquities in fire at Temple in 1838. He was appointed as a queen's counsel in 1851
He stood for Parliament in the 1852 general election for King's Lynn but was not elected.
In 1853 he married Marie, the only daughter of Baron Von Lauer of Berlin. They had three children.
He published two works on economics: On Pauperism (1854), and Observations on the government bill for abolishing the Removal of the Poor (1854).
He died in 1859 at 16, Manchester Square, London and was buried at the Kensal Green cemetery.
Studies of Crete
Pashley was one of the foremost researchers of Cretan culture in the first half of the nineteenth century. Pashley was the first one to work out the location of the ancient buried city of Cydonia, relying only on ancient literature, without the aid of archaeological
|
https://en.wikipedia.org/wiki/Anderson%20localization
|
In condensed matter physics, Anderson localization (also known as strong localization) is the absence of diffusion of waves in a disordered medium. This phenomenon is named after the American physicist P. W. Anderson, who was the first to suggest that electron localization is possible in a lattice potential, provided that the degree of randomness (disorder) in the lattice is sufficiently large, as can be realized for example in a semiconductor with impurities or defects.
Anderson localization is a general wave phenomenon that applies to the transport of electromagnetic waves, acoustic waves, quantum waves, spin waves, etc. This phenomenon is to be distinguished from weak localization, which is the precursor effect of Anderson localization (see below), and from Mott localization, named after Sir Nevill Mott, where the transition from metallic to insulating behaviour is not due to disorder, but to a strong mutual Coulomb repulsion of electrons.
Introduction
In the original Anderson tight-binding model, the evolution of the wave function ψ on the d-dimensional lattice Zd is given by the Schrödinger equation
where the Hamiltonian H is given by
with Ej random and independent, and potential V(r) falling off faster than r−3 at infinity. For example, one may take Ej uniformly distributed in [−W, +W], and
Starting with ψ0 localised at the origin, one is interested in how fast the probability distribution diffuses. Anderson's analysis shows the following:
if d is 1 or 2
|
https://en.wikipedia.org/wiki/Poisson%20kernel
|
In mathematics, and specifically in potential theory, the Poisson kernel is an integral kernel, used for solving the two-dimensional Laplace equation, given Dirichlet boundary conditions on the unit disk. The kernel can be understood as the derivative of the Green's function for the Laplace equation. It is named for Siméon Poisson.
Poisson kernels commonly find applications in control theory and two-dimensional problems in electrostatics.
In practice, the definition of Poisson kernels are often extended to n-dimensional problems.
Two-dimensional Poisson kernels
On the unit disc
In the complex plane, the Poisson kernel for the unit disc is given by
This can be thought of in two ways: either as a function of r and θ, or as a family of functions of θ indexed by r.
If is the open unit disc in C, T is the boundary of the disc, and f a function on T that lies in L1(T), then the function u given by
is harmonic in D and has a radial limit that agrees with f almost everywhere on the boundary T of the disc.
That the boundary value of u is f can be argued using the fact that as , the functions form an approximate unit in the convolution algebra L1(T). As linear operators, they tend to the Dirac delta function pointwise on Lp(T). By the maximum principle, u is the only such harmonic function on D.
Convolutions with this approximate unit gives an example of a summability kernel for the Fourier series of a function in L1(T) . Let f ∈ L1(T) have Fourier series {fk}. After the F
|
https://en.wikipedia.org/wiki/Geometry%20processing
|
Geometry processing, or mesh processing, is an area of research that uses concepts from applied mathematics, computer science and engineering to design efficient algorithms for the acquisition, reconstruction, analysis, manipulation, simulation and transmission of complex 3D models. As the name implies, many of the concepts, data structures, and algorithms are directly analogous to signal processing and image processing. For example, where image smoothing might convolve an intensity signal with a blur kernel formed using the Laplace operator, geometric smoothing might be achieved by convolving a surface geometry with a blur kernel formed using the Laplace-Beltrami operator.
Applications of geometry processing algorithms already cover a wide range of areas from multimedia, entertainment and classical computer-aided design, to biomedical computing, reverse engineering, and scientific computing.
Geometry processing is a common research topic at SIGGRAPH, the premier computer graphics academic conference, and the main topic of the annual Symposium on Geometry Processing.
Geometry processing as a life cycle
Geometry processing involves working with a shape, usually in 2D or 3D, although the shape can live in a space of arbitrary dimensions. The processing of a shape involves three stages, which is known as its life cycle. At its "birth," a shape can be instantiated through one of three methods: a model, a mathematical representation, or a scan. After a shape is born, it can
|
Subsets and Splits
No community queries yet
The top public SQL queries from the community will appear here once available.