source
stringlengths 31
207
| text
stringlengths 12
1.5k
|
|---|---|
https://en.wikipedia.org/wiki/Antide%20Janvier
|
Antide Janvier (1 July 1751 – 23 September 1835) was a French clockmaker.
Life
Antide Janvier was born in a village in the Jura, and learned the basics of his trade from his father, and was educated in Latin, Greek, mathematics and astronomy by a local abbé. At age 15 he built an astronomical sphere which he presented to the Academy of Sciences of Besançon, which won him wide admiration, and he began his career as an apprentice watchmaker.
He gained a reputation as a maker of ingenious and complicated clocks, including many astronomical clocks and clocks showing the tides. He was also famous for his "double pendulum clocks", also called "Resonance clocks", which he was the first to make. He eventually became Louis XVI's royal clockmaker. After the French Revolution he spent time in prison because of this royal association and then fell on hard times; his hardships were increased by the death of his wife in 1792. He sold his watches and equipment and designs to Abraham-Louis Breguet, who sold watches under his own name. Following the restoration of the monarchy under Charles X, he was awarded a small pension beginning in 1826, but died in poverty and obscurity.
Works
He authored and published an important textbook on the theory and practice of watchmaking: "Manuel Chronométrique ou précis de ce qui concerne le temps, ses divisions, ses mesures, leurs usages", Published 1821 by Didot, Paris (267 pages, Frontispiece and 5 engraved foldout plates).
He also produced a wri
|
https://en.wikipedia.org/wiki/Woodville%20Latham
|
Major Woodville Latham (1837–1911) was an ordnance officer of the Confederacy during the American Civil War and professor of chemistry at West Virginia University. He was significant in the development of early film technology.
Woodville Latham was the father of Grey Latham and Otway Latham, owners of a kinetoscope parlor in New York City. In December 1894 Latham and his two sons formed the Lambda Company at 35 Frankfort Street, employing Eugène Lauste, a former Thomas Edison employee, as well as motion picture pioneer William Kennedy Dickson. Dickson would not leave Edison's employ until April 1895 and initially lent his expertise to the Lathams in secret. The Eidoloscope was demonstrated for members of the press on April 21, 1895, and opened to the paying public on May 20, in a lower Broadway store with films of the Griffo-Barnett prize boxing fight, taken from Madison Square Garden's roof on May 4.
In 1898 the Lathams abandoned motion pictures and soon lost their patents. Major Latham outlived his sons; by 1910 both Otway and Grey, who are said to have been hedonistic in nature, had died.
Latham, aided by the collaboration of Dickson and Lauste, is notable for the invention of the Latham loop inside movie cameras and projectors, a significant development in the history of cinema because it allowed motion pictures to be continuously shot and projected for a much longer period than the one-minute films of Thomas Edison's kinetoscope. Shortly before his death in 1911, Lath
|
https://en.wikipedia.org/wiki/Toshio%20Mura
|
was a professor of engineering.
He was born in Ono, a small port village of Kanazawa Japan, on December 7, 1925. He received a doctorate in the Department of Applied Mathematics of the University of Tokyo in 1954. He taught at Meiji University, Japan from 1954 to 1958. In 1958, he went to the United States to work in the Department of Materials Science at Northwestern University in Evanston, Illinois. He became a professor in the Department of Civil Engineering in 1966 before his retirement in 1996, and also held an appointment in the Department of Mechanical Engineering.
Dr. Mura was appointed Walter P. Murphy Professor in the McCormick School of Engineering at Northwestern, was elected as a member of the National Academy of Engineering (NAE) in 1986 for his contributions to the field of micromechanics, and received many other accolades for his work. He was as much recognized for his academic achievement as his generosity in opening his home to visiting scholars and graduate students from Japan, where weekend gatherings were a regular occurrence.
Dr. Mura was interested in the micromechanics of solids. Examples of micromechanics are theories on fracture and fatigue of materials, mathematical analysis for dislocations and inclusions in solids, mechanical characterization of thin films, ceramics and composite materials.
Professor Mura was also interested in the inverse problems. His research aimed to predict inelastic damages in solids by knowing surface displacements
|
https://en.wikipedia.org/wiki/Rodolfo%20Llin%C3%A1s
|
Rodolfo Llinás Riascos (born 16 December 1934) is a Colombian and American neuroscientist. He is currently the Thomas and Suzanne Murphy Professor of Neuroscience and Chairman Emeritus of the Department of Physiology & Neuroscience at the NYU School of Medicine. Llinás has published over 800 scientific articles.
Early life
Llinás was born in Bogotá, Colombia. He is the son of Jorge Enrique Llinás (a surgeon of Spanish descent, whose family arrived in Colombia at the end of the 19th century) and Bertha Riascos. He was motivated to study the brain by watching his grandfather Pablo Llinás Olarte working as a neuropsychiatrist. Llinás describes himself as a logical positivist.
Education and early research
Llinás went to the Gimnasio Moderno school in Bogotá and graduated as a medical doctor from the Pontifical Xavierian University in 1959. During his medical studies he had the opportunity to travel to Europe and there he met several researchers in Spain, France and finally Switzerland, where he participated in neurophysiology experiments with Dr. Walter Rudolf Hess, Nobel Prize in Physiology, Medicine, professor and director of the Department of the Institute of Physiology of the University of Zurich. Additionally, while studying medicine he made a theoretical thesis on the visual system under the tuition of neurosurgeon and neurophysiologist Fernando Rosas and the mathematician Carlo Federici at the National University of Colombia. He received his PhD in 1965 from the Australi
|
https://en.wikipedia.org/wiki/Homogeneous%20catalysis
|
In chemistry, homogeneous catalysis is catalysis where the catalyst is in same phase as reactants, principally by a soluble catalyst a in solution. In contrast, heterogeneous catalysis describes processes where the catalysts and substrate are in distinct phases, typically solid-gas, respectively. The term is used almost exclusively to describe solutions and implies catalysis by organometallic compounds. Homogeneous catalysis is an established technology that continues to evolve. An illustrative major application is the production of acetic acid. Enzymes are examples of homogeneous catalysts.
Examples
Acid catalysis
The proton is a pervasive homogeneous catalyst because water is the most common solvent. Water forms protons by the process of self-ionization of water. In an illustrative case, acids accelerate (catalyze) the hydrolysis of esters:
CH3CO2CH3 + H2O CH3CO2H + CH3OH
At neutral pH, aqueous solutions of most esters do not hydrolyze at practical rates.
Transition metal-catalysis
Hydrogenation and related reactions
A prominent class of reductive transformations are hydrogenations. In this process, H2 added to unsaturated substrates. A related methodology, transfer hydrogenation, involves by transfer of hydrogen from one substrate (the hydrogen donor) to another (the hydrogen acceptor). Related reactions entail "HX additions" where X = silyl (hydrosilylation) and CN (hydrocyanation). Most large-scale industrial hydrogenations – margarine, ammonia, benzene-to-cyclohex
|
https://en.wikipedia.org/wiki/Collision%20theory
|
Collision theory is a principle of chemistry used to predict the rates of chemical reactions. It states that when suitable particles of the reactant hit each other with the correct orientation, only a certain amount of collisions result in a perceptible or notable change; these successful changes are called successful collisions. The successful collisions must have enough energy, also known as activation energy, at the moment of impact to break the pre-existing bonds and form all new bonds. This results in the products of the reaction. The activation energy is often predicted using the Transition state theory. Increasing the concentration of the reactant brings about more collisions and hence more successful collisions. Increasing the temperature increases the average kinetic energy of the molecules in a solution, increasing the number of collisions that have enough energy. Collision theory was proposed independently by Max Trautz in 1916 and William Lewis in 1918.
When a catalyst is involved in the collision between the reactant molecules, less energy is required for the chemical change to take place, and hence more collisions have sufficient energy for the reaction to occur. The reaction rate therefore increases.
Collision theory is closely related to chemical kinetics.
Collision theory was initially developed for the gas reaction system with no dilution. But most reactions involve solutions, for example, gas reactions in a carrying inert gas, and almost all reactions
|
https://en.wikipedia.org/wiki/MEI
|
MEI may refer to:
Education
MEI Academy, an international school
Mathematics in Education and Industry, an examination board affiliated with the OCR examination board
Mennonite Educational Institute, an independent grades K-12 school in Abbotsford, British Columbia
Businesses
MEI (company), manufacturer of cash handling systems
Matsushita Electric Industrial Co., Ltd.
Micro Electronics, Inc.
Member of the Energy Institute (MEI)
, an annual conference of Italian independent record labels
Government
Ministry of Economy and Innovation (), the Portuguese economy ministry
Middle East Institute
Marginal efficiency of investment or internal rate of return, a relationship between interest rate and amount of investment that can be profitable at a given time
Meridian Regional Airport
Montreal Economic Institute
Meridian (Amtrak station), Amtrak station code MEI, Mississippi, United States
Medicare Economic Index
Military
MEI Hellhound (Grenade), low velocity multipurpose grenade
MEI Mercury, a family of grenades developed by Martin Electronics, Inc.
Science
Iodomethane (methyl iodide, MeI), a halomethane
Multivariate ENSO index
4-Methylimidazole (4-MEI), a chemical compound
Technology
Management Engine Interface, a component of Intel Active Management Technology
Music Encoding Initiative, a music encoding format
Other uses
Media and Entertainment International, a former global union federation
OECD Main Economic Indicators, a monthly publication of t
|
https://en.wikipedia.org/wiki/Heterochrony
|
In evolutionary developmental biology, heterochrony is any genetically controlled difference in the timing, rate, or duration of a developmental process in an organism compared to its ancestors or other organisms. This leads to changes in the size, shape, characteristics and even presence of certain organs and features. It is contrasted with heterotopy, a change in spatial positioning of some process in the embryo, which can also create morphological innovation. Heterochrony can be divided into intraspecific heterochrony, variation within a species, and interspecific heterochrony, phylogenetic variation, i.e. variation of a descendant species with respect to an ancestral species.
These changes all affect the start, end, rate or time span of a particular developmental process. The concept of heterochrony was introduced by Ernst Haeckel in 1875 and given its modern sense by Gavin de Beer in 1930.
History
The concept of heterochrony was introduced by the German zoologist Ernst Haeckel in 1875, where he used it to define deviations from recapitulation theory, which held that "ontogeny recapitulates phylogeny". As Stephen Jay Gould pointed out, Haeckel's term is now used in a sense contrary to his coinage; Haeckel had assumed that embryonic development (ontogeny) of "higher" animals recapitulated their ancestral development (phylogeny), as when mammal embryos have structures on the neck that resemble fish gills at one stage. This, in his view, necessarily compressed the earlie
|
https://en.wikipedia.org/wiki/Phenol%20red
|
Phenol red (also known as phenolsulfonphthalein or PSP) is a pH indicator frequently used in cell biology laboratories.
Chemical structure and properties
Phenol red exists as a red crystal that is stable in air. Its solubility is 0.77 grams per liter (g/L) in water and 2.9 g/L in ethanol. It is a weak acid with pKa = 8.00 at .
A solution of phenol red is used as a pH indicator, often in cell culture. Its color exhibits a gradual transition from yellow (λmax = 443 nm) to red (λmax = 570 nm) over the pH range 6.8 to 8.2. Above pH 8.2, phenol red turns a bright pink (fuchsia) color.
In crystalline form, and in solution under very acidic conditions (low pH), the compound exists as a zwitterion as in the structure shown above, with the sulfate group negatively charged, and the ketone group carrying an additional proton. This form is sometimes symbolically written as and is orange-red. If the pH is increased (pKa = 1.2), the proton from the ketone group is lost, resulting in the yellow, negatively charged ion denoted as HPS−. At still higher pH (pKa = 7.7), the phenol's hydroxy group loses its proton, resulting in the red ion denoted as PS2−.
In several sources, the structure of phenol red is shown with the sulfur atom being part of a cyclic group, similar to the structure of phenolphthalein. However, this cyclic structure could not be confirmed by X-ray crystallography.
Several indicators share a similar structure to phenol red, including bromothymol blue, thymol blue, bromo
|
https://en.wikipedia.org/wiki/The%20Schoolmaster%27s%20Assistant%2C%20Being%20a%20Compendium%20of%20Arithmetic%20Both%20Practical%20and%20Theoretical
|
The Schoolmaster's Assistant, Being a Compendium of Arithmetic both Practical and Theoretical was an early and popular English arithmetic textbook, written by Thomas Dilworth and first published in England in 1743. An American edition was published in 1769; by 1786 it had reached 23 editions, and through 1800 it was the most popular mathematics text in America.
Sections
Although different editions of the book varied in content according to the whims of their publishers, most editions of the book reached from the introductory topics to the advanced in five sections:
Section I, Whole Numbers included the basis of the four operations and proceeded to topics on interest, rebates, partnership, weights and measures, the double rule of three, alligation, mediation and permutations.
Section II dealt with common fractions.
Section III dealt with decimal fraction operations and included roots up to the fourth power, and work on annuities and pensions.
Section IV was a collection of 104 word problems to be solved. As was common in many older texts, the questions were sometimes stated in rhyme. Lessons for students were for memorization and recitation.
Section V was on duodecimals, working with fractions in which the only denominators were twelfths. These types of problems continue in textbooks and appear in the 1870 edition of White's Complete Arithmetic in the appendix. The definition states: A Duodecimal is a denominate number in which twelve units of any denomination make a unit o
|
https://en.wikipedia.org/wiki/Okazaki
|
Okazaki may refer to:
Okazaki (surname)
Okazaki, Aichi, a city in Japan
Okazaki Castle, a castle in Japan
Okazaki fragments, DNA fragments formed during DNA replication (biology)
See also
Okasaki
|
https://en.wikipedia.org/wiki/Preon
|
In particle physics, preons are hypothetical point particles, conceived of as sub-components of quarks and leptons. The word was coined by Jogesh Pati and Abdus Salam, in 1974. Interest in preon models peaked in the 1980s but has slowed, as the Standard Model of particle physics continues to describe physics mostly successfully, and no direct experimental evidence for lepton and quark compositeness has been found. Preons come in four varieties: plus, anti-plus, zero, and anti-zero. W bosons have six preons, and quarks and leptons have only three.
In the hadronic sector, some effects are considered anomalies within the Standard Model. For example, the proton spin puzzle, the EMC effect, the distributions of electric charges inside the nucleons, as found by Hofstadter in 1956, and the ad hoc CKM matrix elements.
When the term "preon" was coined, it was primarily to explain the two families of spin- fermions: quarks and leptons. More recent preon models also account for spin-1 bosons, and are still called "preons". Each of the preon models postulates a set of fewer fundamental particles than those of the Standard Model, together with the rules governing how those fundamental particles combine and interact. Based on these rules, the preon models try to explain the Standard Model, often predicting small discrepancies with this model and generating new particles and certain phenomena which do not belong to the Standard Model.
Goals of preon models
Preon research is motivated by
|
https://en.wikipedia.org/wiki/FANUC
|
FANUC ( or ; often styled Fanuc) is a Japanese group of companies that provide automation products and services such as robotics and computer numerical control wireless systems. These companies are principally of Japan, Fanuc America Corporation of Rochester Hills, Michigan, USA, and FANUC Europe Corporation S.A. of Luxembourg.
FANUC is one of the largest makers of industrial robots in the world. FANUC had its beginnings as part of Fujitsu developing early numerical control (NC) and servo systems. FANUC is acronym for Fuji Automatic NUmerical Control.
FANUC is organized into 3 business units: FA (Factory Automation), ROBOT, and ROBOMACHINE. These three units are unified with SERVICE as "one FANUC". Service is an integral part of FANUC and the company famously supports products for as long as customers use them.
History
In 1955, Fujitsu Ltd. approached Seiuemon Inaba (:ja:稲葉清右衛門), who was then a young engineer, to lead a new subsidiary purposed to make the field of numerical control. This nascent form of automation involved sending instructions encoded into punched cards or magnetic tape to motors that controlled the movement of tools, effectively creating programmable versions of the lathes, presses, and milling machines. Within three years after spending heavily in R&D, he and his team of 500 employees shipped Fujitsu's first numerical-control machine to Makino Milling Machine Co. In 1972, the Computing Control Division became independent and FANUC Ltd. was established.
|
https://en.wikipedia.org/wiki/Stolon
|
In biology, stolons (from Latin stolō, genitive stolōnis – "branch"), also known as runners, are horizontal connections between parts of an organism. They may be part of the organism, or of its skeleton. Typically, animal stolons are exoskeletons (external skeletons).
In botany
In botany, stolons are plant stems which grow at the soil surface or just below ground that form adventitious roots at the nodes, and new plants from the buds. Stolons are often called runners. Rhizomes, in contrast, are root-like stems that may either grow horizontally at the soil surface or in other orientations underground. Thus, not all horizontal stems are called stolons. Plants with stolons are called stoloniferous.
A stolon is a plant propagation strategy and the complex of individuals formed by a mother plant and all its clones produced from stolons form a single genetic individual, a genet.
Morphology
Stolons may have long or short internodes. The leaves along the stolon are usually very small, but in a few cases such as Stachys sylvatica are normal in size.
Stolons arise from the base of the plant. In strawberries the base is above the soil surface; in many bulb-forming species and plants with rhizomes, the stolons remain underground and form shoots that rise to the surface at the ends or from the nodes. The nodes of the stolons produce roots, often all around the node and hormones produced by the roots cause the stolon to initiate shoots with normal leaves. Typically after the formation
|
https://en.wikipedia.org/wiki/Potential%20theory
|
In mathematics and mathematical physics, potential theory is the study of harmonic functions.
The term "potential theory" was coined in 19th-century physics when it was realized that two fundamental forces of nature known at the time, namely gravity and the electrostatic force, could be modeled using functions called the gravitational potential and electrostatic potential, both of which satisfy Poisson's equation—or in the vacuum, Laplace's equation.
There is considerable overlap between potential theory and the theory of Poisson's equation to the extent that it is impossible to draw a distinction between these two fields. The difference is more one of emphasis than subject matter and rests on the following distinction: potential theory focuses on the properties of the functions as opposed to the properties of the equation. For example, a result about the singularities of harmonic functions would be said to belong to potential theory whilst a result on how the solution depends on the boundary data would be said to belong to the theory of the Laplace equation. This is not a hard and fast distinction, and in practice there is considerable overlap between the two fields, with methods and results from one being used in the other.
Modern potential theory is also intimately connected with probability and the theory of Markov chains. In the continuous case, this is closely related to analytic theory. In the finite state space case, this connection can be introduced by introducing
|
https://en.wikipedia.org/wiki/Rock%20Abrasion%20Tool
|
The Rock Abrasion Tool (RAT) is a grinding and brushing installation on NASA’s twin Mars Exploration Rovers, Spirit (MER-A) and Opportunity (MER-B), which landed on Mars in January 2004. It was designed, developed and continues to be operated by Honeybee Robotics LTD, a developer of specialized robots, automated technologies and related systems.
The RAT was the first machine to gain access to the interior of rocks on another planet. The RAT has a mass of , is in diameter and long, about the size of a soda can. It uses a diamond dust and resin wheel spinning at 3000 rpm to drill a 45 mm diameter by 5 mm deep bore hole in martian rocks. The RAT then uses two brushes to sweep dust from the bore holes for closer scientific inspection. Its average power consumption is 30 watts.
There are five other instruments aboard both rovers, these are the Pancam (a camera), Mini-TES (an infrared spectrometer) for sensing targets at a distance, a microscopic imager, a Mössbauer spectrometer and an alpha particle X-ray spectrometer. The RAT provides these instruments with a smooth, clean surface from which they make more accurate observations.
The RAT was first used by Spirit on its 34th sol (February 6, 2004). It was held up to the rock Adirondack, whereby it scraped to a depth of over the course of three hours. Since then it has been used on numerous Martian rocks by both MER rovers.
The RAT was originally controlled from NASA's Jet Propulsion Laboratory in Pasadena, California, but is
|
https://en.wikipedia.org/wiki/Robert%20B.%20Leighton
|
Robert Benjamin Leighton (; September 10, 1919 – March 9, 1997) was a prominent American experimental physicist who spent his professional career at the California Institute of Technology (Caltech). His work over the years spanned solid state physics, cosmic ray physics, the beginnings of modern particle physics, solar physics, the planets, infrared astronomy, and millimeter- and submillimeter-wave astronomy. In the latter four fields, his pioneering work opened up entirely new areas of research that subsequently developed into vigorous scientific communities.
Early life
Leighton was born in Detroit, where his father made precision dies for an automobile company. After moving to Seattle the family broke up, and his father returned to Detroit. His mother moved to downtown Los Angeles, where she worked as a maid in a hotel. Leighton grew up in Los Angeles and completed his first two years of undergraduate coursework at Los Angeles City College. He was accepted to Caltech as a junior in 1939 but continued to live at home, helping support his mother and himself with a job building X-ray equipment for the Kellogg Laboratory.
Education and Caltech
Leighton received his BS in electrical engineering from Caltech in 1941. He then switched to physics and went on to obtain MS (1944) and PhD (1947) degrees from the institution. His doctoral dissertation explored the specific heat of face-centered cubic crystals. He joined Caltech's faculty in 1949 and served as Division Chair of Phys
|
https://en.wikipedia.org/wiki/Paul%20Benacerraf
|
Paul Joseph Salomon Benacerraf (; born 26 March 1931) is a French-born American philosopher working in the field of the philosophy of mathematics who taught at Princeton University his entire career, from 1960 until his retirement in 2007. He was appointed Stuart Professor of Philosophy in 1974, and retired as the James S. McDonnell Distinguished University Professor of Philosophy.
Life and career
Benacerraf was born in Paris to a Moroccan-Venezuelan father and an Algerian mother. In 1939 the family moved to Caracas and then to New York City.
When the family returned to Caracas, Benacerraf remained in the United States, boarding at the Peddie School in Hightstown, New Jersey. He attended Princeton University for both his undergraduate and graduate studies.
He was elected a fellow of the American Academy of Arts and Sciences in 1998.
His brother was the Venezuelan Nobel Prize-winning immunologist Baruj Benacerraf.
Philosophical work
Benacerraf is perhaps best known for his two papers "What Numbers Could Not Be" (1965) and "Mathematical Truth" (1973), and for his anthology on the philosophy of mathematics, co-edited with Hilary Putnam.
In "What Numbers Could Not Be" (1965), Benacerraf argues against a Platonist view of mathematics, and for structuralism, on the ground that what is important about numbers is the abstract structures they represent rather than the objects that number words ostensibly refer to. In particular, this argument is based on the point that Ernst
|
https://en.wikipedia.org/wiki/Schwarz%20lemma
|
In mathematics, the Schwarz lemma, named after Hermann Amandus Schwarz, is a result in complex analysis about holomorphic functions from the open unit disk to itself. The lemma is less celebrated than deeper theorems, such as the Riemann mapping theorem, which it helps to prove. It is, however, one of the simplest results capturing the rigidity of holomorphic functions.
Statement
Let be the open unit disk in the complex plane centered at the origin, and let be a holomorphic map such that and on .
Then for all , and .
Moreover, if for some non-zero or , then for some with .
Proof
The proof is a straightforward application of the maximum modulus principle on the function
which is holomorphic on the whole of , including at the origin (because is differentiable at the origin and fixes zero). Now if denotes the closed disk of radius centered at the origin, then the maximum modulus principle implies that, for , given any , there exists on the boundary of such that
As we get .
Moreover, suppose that for some non-zero , or . Then, at some point of . So by the maximum modulus principle, is equal to a constant such that . Therefore, , as desired.
Schwarz–Pick theorem
A variant of the Schwarz lemma, known as the Schwarz–Pick theorem (after Georg Pick), characterizes the analytic automorphisms of the unit disc, i.e. bijective holomorphic mappings of the unit disc to itself:
Let be holomorphic. Then, for all ,
and, for all ,
The expression
is the distanc
|
https://en.wikipedia.org/wiki/Nick%20D.%20Kim
|
Nicholas D. Kim is an analytical environmental chemist and cartoonist who currently works as a senior lecturer in applied environmental chemistry, School of Public health, College of Health for Massey University in Wellington, New Zealand. As a cartoonist he is known under his pseudonym Nick. He specializes in environmental chemistry and contamination issues and is certified to practice as an independent hearings commissioner under New Zealand's Resource Management Act. Previously he has acted as a science advisor for the Waikato Regional Council and as a senior lecturer in chemistry at the University of Waikato.
Biography
Kim completed a BSc(Hons) in 1987 and PhD in 1990 at the University of Canterbury in New Zealand, followed by postdoctoral research at the Australian National University. From 1991 to 2001 Kim worked as a lecturer and senior lecturer in at the University of Waikato in Hamilton, New Zealand, where he developed teaching and research interests in environmental chemistry, analytical chemistry and forensic science. It was during this period that Kim started creating science cartoons, which were initially published on Usenet and subsequently developed to an online archive hosted at Ohio State University, and (in print form) New Zealand Science Monthly. In the subsequent decade from 2002 to 2011 Kim worked as a scientist at the Waikato Regional Council, a local government region of the upper North Island of New Zealand, specialising in scientific and regulatory
|
https://en.wikipedia.org/wiki/Hodgkin
|
Hodgkin is a surname. Notable people with the surname include:
Alan Lloyd Hodgkin (1914–1998), British physiologist and biophysicist
Dorothy Hodgkin (1910–1994), British chemist who received the Nobel Prize in Chemistry in 1964, wife of Thomas Lionel Hodgkin
Douglas Hodgkin, American political scientist and author
Eliot Hodgkin (1905–1987), British painter
Howard Hodgkin (1932–2017), British painter
John Hodgkin (barrister) (1800–1875), English barrister and Quaker preacher, brother of Thomas Hodgkin (1798–1866)
Robert Howard Hodgkin (1877–1951), English historian, son of Thomas Hodgkin (1831–1913)
Thomas Hodgkin (1798–1866), English pathologist, eponym of Hodgkin's disease
Thomas Hodgkin (historian) (1831–1913), British historian, son of John Hodgkin
Thomas Lionel Hodgkin (1910–1982), English historian, son of Robert Howard Hodgkin, husband of Dorothy Hodgkin
See also
Hodgkins (disambiguation)
Hodgkin lymphoma, also known as Hodgkin's lymphoma and Hodgkin's disease
Hodgkin family, the Quaker family
English-language surnames
Patronymic surnames
Surnames from given names
|
https://en.wikipedia.org/wiki/Autoregressive%20model
|
In statistics, econometrics, and signal processing, an autoregressive (AR) model is a representation of a type of random process; as such, it is used to describe certain time-varying processes in nature, economics, behavior, etc. The autoregressive model specifies that the output variable depends linearly on its own previous values and on a stochastic term (an imperfectly predictable term); thus the model is in the form of a stochastic difference equation (or recurrence relation which should not be confused with differential equation). Together with the moving-average (MA) model, it is a special case and key component of the more general autoregressive–moving-average (ARMA) and autoregressive integrated moving average (ARIMA) models of time series, which have a more complicated stochastic structure; it is also a special case of the vector autoregressive model (VAR), which consists of a system of more than one interlocking stochastic difference equation in more than one evolving random variable.
Contrary to the moving-average (MA) model, the autoregressive model is not always stationary as it may contain a unit root.
Definition
The notation indicates an autoregressive model of order p. The AR(p) model is defined as
where are the parameters of the model, and is white noise. This can be equivalently written using the backshift operator B as
so that, moving the summation term to the left side and using polynomial notation, we have
An autoregressive model can thus be view
|
https://en.wikipedia.org/wiki/Typesafe
|
Typesafe may refer to:
Type safety, a concept in computer science, in which a programming language discourages or prevents type errors
Typesafe Inc. (renamed to Lightbend), a company founded by Martin Odersky and the creators of the Scala programming language and Akka middleware
|
https://en.wikipedia.org/wiki/RSN
|
The initials RSN may refer to:
"Real Soon Now"
Regional sports network
Renal Support Network
Republic of Singapore Navy
Resort Sports Network
Robust Security Network in IEEE 802.11i-2004 (WPA2)
Royal School of Needlework
Royal Saudi Navy
RSN Racing & Sport
RSn may refer to:
Organotin chemistry and related compounds
|
https://en.wikipedia.org/wiki/ELT
|
ELT may refer to:
Education
English language teaching
Expanded learning time, an American education strategy
Kolb's experiential learning theory
Mathematics and science
Ending lamination theorem
Extremely large telescope, a type of telescope
Extremely Large Telescope, an astronomical observatory under construction in Chile
Effective lifetime temperature, used in rehydroxylation dating
Medicine
Endovenous laser treatment
Euglobulin lysis time
Excimer laser trabeculostomy
Music
Every Little Thing (band), a Japanese J-Pop band
"ELT", a song by the band Wilco from their 1999 album Summerteeth
Technology
Emergency locator transmitter
Extract, load, transform, a data processing concept
End-of-life tyre
Transport
East London Transit, a British public transport system
El Tor Airport, in Egypt
Elizabethtown station, Pennsylvania
Other uses
Electrical lighting technician, a stage-lighting technician
Electronic lien and title
Elt Drenth (1949–1998), Dutch swimmer
Evolutionary leadership theory
Executive Leadership Team
|
https://en.wikipedia.org/wiki/Eugeniusz%20Kwiatkowski
|
Eugeniusz Kwiatkowski (30 December 1888, Kraków – 22 August 1974, Kraków) was a Polish politician and economist, Deputy Prime Minister of Poland, government minister and manager of the Second Polish Republic.
Biography
He studied at the prestigious Jesuit college in Chyrów, and then graduated chemistry at the University of Lwów and Ludwig Maximilian University of Munich.
After Józef Piłsudski's May coup d'état of 1926 in the Second Polish Republic, he was recommended by president Ignacy Mościcki for the post Minister of Industry and Trade in the government of Kazimierz Bartel. Kwiatkowski was a minister in eight successive governments (1926–30) and Deputy Prime Minister of Poland and Minister of Finance of Poland in two governments (1935–39).
Among the most famous achievements of Kwiatkowski are the giant construction projects: the construction of Gdynia seaport, the development of the Polish Merchant Navy and sea trade, and the creation of Centralny Okręg Przemysłowy (The Central Industrial Region).
After the Soviet Union joined Nazi Germany in the invasion of Poland in 1939, he evacuated Poland with the rest of the Government on 17 September. He was interned in Romania until 1945. He returned to Poland and supervised the projects of reconstruction of the Polish seacoast, and in the years 1947–1952, he was a deputy to the Polish parliament (Sejm).
With the strengthening of the communist and Soviet grip on the Polish government, which he opposed, he fell out of favour o
|
https://en.wikipedia.org/wiki/Transition%20point
|
In the field of fluid dynamics the point at which the boundary layer changes from laminar to turbulent is called the transition point. Where and how this transition occurs depends on the Reynolds number, the pressure gradient, pressure fluctuations due to sound, surface vibration, the initial turbulence level of the flow, boundary layer suction, surface heat flows, and surface roughness. The effects of a boundary layer turned turbulent are an increase in drag due to skin friction. As speed increases, the upper surface transition point tends to move forward. As the angle of attack increases, the upper surface transition point also tends to move forward.
Position
The exact position of the transition point is hard to determine due to it being dependent on a large amount of factors. Several methods to predict it to a certain degree of accuracy do exist, however. Most of these methods revolve around analysing the stability of the (laminar) boundary layer using stability theory: a laminar boundary layer may become unstable due to small disturbances, turning it turbulent. One such method assessing the transition point this way is the eN method.
eN method
The eN method works by superimposing small disturbances on the flow, considering it to be laminar. The assumption is made that both the original and the newly disturbed flow satisfy the Navier-Stokes equations. This disturbed flow can be linearised and described with a perturbation equation. This equation may have unstable soluti
|
https://en.wikipedia.org/wiki/Nucleotide%20diversity
|
Nucleotide diversity is a concept in molecular genetics which is used to measure the degree of polymorphism within a population.
One commonly used measure of nucleotide diversity was first introduced by Nei and Li in 1979. This measure is defined as the average number of nucleotide differences per site between two DNA sequences in all possible pairs in the sample population, and is denoted by .
An estimator for is given by:
where and are the respective frequencies of the th and th sequences, is the number of nucleotide differences per nucleotide site between the th and th sequences, and is the number of sequences in the sample. The term in front of the sums guarantees an unbiased estimator, which does not depend on how many sequences you sample.
Nucleotide diversity is a measure of genetic variation. It is usually associated with other statistical measures of population diversity, and is similar to expected heterozygosity. This statistic may be used to monitor diversity within or between ecological populations, to examine the genetic variation in crops and related species, or to determine evolutionary relationships.
Nucleotide diversity can be calculated by examining the DNA sequences directly, or may be estimated from molecular marker data, such as Random Amplified Polymorphic DNA (RAPD) data and Amplified Fragment Length Polymorphism (AFLP) data.
Software
DnaSP — DNA Sequence Polymorphism, is a software package for the analysis of nucleotide polymorp
|
https://en.wikipedia.org/wiki/Voigt%20notation
|
In mathematics, Voigt notation or Voigt form in multilinear algebra is a way to represent a symmetric tensor by reducing its order. There are a few variants and associated names for this idea: Mandel notation, Mandel–Voigt notation and Nye notation are others found. Kelvin notation is a revival by Helbig of old ideas of Lord Kelvin. The differences here lie in certain weights attached to the selected entries of the tensor. Nomenclature may vary according to what is traditional in the field of application.
For example, a 2×2 symmetric tensor X has only three distinct elements, the two on the diagonal and the other being off-diagonal. Thus it can be expressed as the vector
.
As another example:
The stress tensor (in matrix notation) is given as
In Voigt notation it is simplified to a 6-dimensional vector:
The strain tensor, similar in nature to the stress tensor—both are symmetric second-order tensors --, is given in matrix form as
Its representation in Voigt notation is
where , , and are engineering shear strains.
The benefit of using different representations for stress and strain is that the scalar invariance
is preserved.
Likewise, a three-dimensional symmetric fourth-order tensor can be reduced to a 6×6 matrix.
Mnemonic rule
A simple mnemonic rule for memorizing Voigt notation is as follows:
Write down the second order tensor in matrix form (in the example, the stress tensor)
Strike out the diagonal
Continue on the third column
Go back to the first eleme
|
https://en.wikipedia.org/wiki/Guiding%20center
|
In physics, the motion of an electrically charged particle such as an electron or ion in a plasma in a magnetic field can be treated as the superposition of a relatively fast circular motion around a point called the guiding center and a relatively slow drift of this point. The drift speeds may differ for various species depending on their charge states, masses, or temperatures, possibly resulting in electric currents or chemical separation.
Gyration
If the magnetic field is uniform and all other forces are absent, then the Lorentz force will cause a particle to undergo a constant acceleration perpendicular to both the particle velocity and the magnetic field. This does not affect particle motion parallel to the magnetic field, but results in circular motion at constant speed in the plane perpendicular to the magnetic field. This circular motion is known as the gyromotion. For a particle with mass and charge moving in a magnetic field with strength , it has a frequency, called the gyrofrequency or cyclotron frequency, of
For a speed perpendicular to the magnetic field of , the radius of the orbit, called the gyroradius or Larmor radius, is
Parallel motion
Since the magnetic Lorentz force is always perpendicular to the magnetic field, it has no influence (to lowest order) on the parallel motion. In a uniform field with no additional forces, a charged particle will gyrate around the magnetic field according to the perpendicular component of its velocity and drift paral
|
https://en.wikipedia.org/wiki/Slime
|
Slime may refer to:
Biology
Slime coat, the coating of mucus covering the body of all fish
Slime mold, a broad term often referring to roughly six groups of Eukaryotes
Biofilm, an aggregate of microorganisms in which cells adhere to each other and/or to a surface
Slimy (fish), also known as the ponyfish
Snail slime, the mucus used by gastropods for locomotion
Subsurface Lithoautotrophic Microbial Ecosystem (SLiME), a biotope occupied by 'slime'.
Chemistry
Gunge (UK) or Slime (US), a thick, gooey, yet runny substance used in children's TV programmes.
Flubber (material), a rubbery polymer commonly called slime.
Slimes, another name for tailings, a waste material left after the process of separation of ores
Computing
SLIME, the Superior Lisp Interaction Mode for Emacs, an Emacs mode for developing Common Lisp applications
Geography
Slime, a village, population 270, near Omiš, Croatia
Fiction
"Slime" (short story) (Russian: тина), a short story by Anton Chekhov
"Slime", a novelette by Joseph Payne Brennan. Originally published in the March 1953 issue of Weird Tales
Slimey the Worm, the pet of Oscar the Grouch on Sesame Street
Slime (Dragon Quest), the mascot of the Dragon Quest console role-playing game franchise
Slimer, a green ghost made of slime from the film Ghostbusters
Slime, a hostile mob from Minecraft that splits into multiple smaller slimes when killed.
Slime Princess, a character in the Adventure Time
Brands
Slime (toy), a viscous, oozing g
|
https://en.wikipedia.org/wiki/Velocity-addition%20formula
|
In relativistic physics, a velocity-addition formula is an equation that specifies how to combine the velocities of objects in a way that is consistent with the requirement that no object's speed can exceed the speed of light. Such formulas apply to successive Lorentz transformations, so they also relate different frames. Accompanying velocity addition is a kinematic effect known as Thomas precession, whereby successive non-collinear Lorentz boosts become equivalent to the composition of a rotation of the coordinate system and a boost.
Standard applications of velocity-addition formulas include the Doppler shift, Doppler navigation, the aberration of light, and the dragging of light in moving water observed in the 1851 Fizeau experiment.
The notation employs as velocity of a body within a Lorentz frame , and as velocity of a second frame , as measured in , and as the transformed velocity of the body within the second frame.
History
The speed of light in a fluid is slower than the speed of light in vacuum, and it changes if the fluid is moving along with the light. In 1851, Fizeau measured the speed of light in a fluid moving parallel to the light using an interferometer. Fizeau's results were not in accord with the then-prevalent theories. Fizeau experimentally correctly determined the zeroth term of an expansion of the relativistically correct addition law in terms of as is described below. Fizeau's result led physicists to accept the empirical validity of the rather
|
https://en.wikipedia.org/wiki/Jon%20Hall%20%28programmer%29
|
Jon "maddog" Hall (born 7 August 1950) is the board chair for the Linux Professional Institute.
Career
The nickname "maddog" was given to him by his students at Hartford State Technical College, where he was the Department Head of Computer Science. He now prefers to be called by this name. According to Hall, his nickname "came from a time when I had less control over my temper".
He has worked for Western Electric Corporation, Aetna Life and Casualty, Bell Laboratories, Digital Equipment Corporation (Digital), VA Linux Systems, and Silicon Graphics (SGI). He was the CTO and ambassador of the now defunct computer appliance company Koolu.
It was during his time with Digital that he initially became interested in Linux and was instrumental in obtaining equipment and resources for Linus Torvalds to accomplish his first port, to Digital's Alpha platform. It was also in this general timeframe that Hall, who lives in New Hampshire, started the Greater New Hampshire Linux Users' Group. Hall has UNIX as his New Hampshire vanity license plate.
Hall serves or has served on the boards of several companies, and several non-profit organizations, including the USENIX Association. Hall has spoken about Linux and free software at the technology conference Campus Party many times since 2007.
Hall holds a Master of Science in Computer Science from Rensselaer Polytechnic Institute (1977) and a Bachelor of Science in Commerce and Engineering from Drexel University (1973).
In September 2015
|
https://en.wikipedia.org/wiki/Degree%20of%20curvature
|
Degree of curve or degree of curvature is a measure of curvature of a circular arc used in civil engineering for its easy use in layout surveying.
Definition
The degree of curvature is defined as the central angle to the ends of an agreed length of either an arc or a chord; various lengths are commonly used in different areas of practice. This angle is also the change in forward direction as that portion of the curve is traveled. In an n-degree curve, the forward bearing changes by n degrees over the standard length of arc or chord.
Usage
Curvature is usually measured in radius of curvature. A small circle can be easily laid out by just using radius of curvature, but degree of curvature is more convenient for calculating and laying out the curve if the radius is large as a kilometer or a mile, as it needed for large scale works like roads and railroads. By using degrees of curvature, curve setting can be easily done with the help of a transit or theodolite and a chain, tape, or rope of a prescribed length.
Length selection
The usual distance used to compute degree of curvature in North American road work is of arc. Conversely, North American railroad work traditionally used 100 feet of chord, which is used in other places for road work. Other lengths may be used—such as where SI is favoured or a shorter length for sharper curves. Where degree of curvature is based on 100 units of arc length, the conversion between degree of curvature and radius is , where is degree and
|
https://en.wikipedia.org/wiki/134%20%28number%29
|
134 (one hundred [and] thirty-four) is the natural number following 133 and preceding 135.
In mathematics
134 is a nontotient since there is no integer with exactly 134 coprimes below it. And it is a noncototient since there is no integer with 134 integers with common factors below it.
134 is .
In Roman numerals, 134 is a Friedman number since CXXXIV = XV * (XC/X) - I.
In the military
was a Mission Buenaventura-class fleet oiler during World War II
was a United States Navy during World War II
was a United States Navy between World War I and World War II
was the lead ship of the United States Navy heavy cruisers during World War II
was a United States Navy General G. O. Squier-class transport ship during World War II
was a United States Navy converted steel-hulled trawler, during World War II
was a United States Navy which saw battle during the Battle of Midway
was a United States Navy during World War II
, was a United States S-class submarine which was later transferred to the Royal Navy
was a United States Navy Crater-class cargo ship during World War II
134 (Bedford) Squadron in the United Kingdom Air Training Corps
The 134th (48th Highlanders) Battalion, CEF was a Toronto, Ontario unit of the Canadian Expeditionary Force during World War I
The 134th Pennsylvania Volunteer Infantry was an infantry regiment in the Union Army during the American Civil War
In sports
Former running back George Reed for the Saskatchewan Roughriders held the car
|
https://en.wikipedia.org/wiki/Saha%20ionization%20equation
|
In physics, the Saha ionization equation is an expression that relates the ionization state of a gas in thermal equilibrium to the temperature and pressure. The equation is a result of combining ideas of quantum mechanics and statistical mechanics and is used to explain the spectral classification of stars. The expression was developed by physicist Meghnad Saha in 1920.
Description
For a gas at a high enough temperature (here measured in energy units, i.e. keV or J) and/or density, the thermal collisions of the atoms will ionize some of the atoms, making an ionized gas. When several or more of the electrons that are normally bound to the atom in orbits around the atomic nucleus are freed, they form an independent electron gas cloud co-existing with the surrounding gas of atomic ions and neutral atoms. With sufficient ionization, the gas can become the state of matter called plasma.
The Saha equation describes the degree of ionization for any gas in thermal equilibrium as a function of the temperature, density, and ionization energies of the atoms. The Saha equation only holds for weakly ionized plasmas for which the Debye length is small. This means that the screening of the Coulomb interaction of ions and electrons by other ions and electrons is negligible. The subsequent lowering of the ionization potentials and the "cutoff" of the partition function is therefore also negligible.
For a gas composed of a single atomic species, the Saha equation is written:
where:
is
|
https://en.wikipedia.org/wiki/Michael%20Ruse
|
Michael Ruse (born 21 June 1940) is a British-born Canadian philosopher of science who specializes in the philosophy of biology and works on the relationship between science and religion, the creation–evolution controversy, and the demarcation problem within science. Ruse currently teaches at Florida State University.
Career
Ruse was born in Birmingham, England, attending Bootham School, York. He took his undergraduate degree at the University of Bristol (1962), his master's degree at McMaster University, Hamilton, Ontario (1964), and Ph.D. at the University of Bristol (1970).
Ruse taught at the University of Guelph in Ontario, Canada for 35 years. Since his retirement from Guelph, he has taught at Florida State University and is the Lucyle T. Werkmeister Professor of Philosophy (2000–present). In 1986, he was elected as a Fellow of both the Royal Society of Canada and the American Association for the Advancement of Science. He has received honorary doctorates from the University of Bergen, Norway (1990), McMaster University, Ontario, Canada (2003) and the University of New Brunswick, Fredericton, New Brunswick, Canada (2007). In September 2014 he was made an Honorary Doctor of Science by University College London.
Ruse was a key witness for the plaintiff in the 1981 test case (McLean v. Arkansas) of the state law permitting the teaching of "creation science" in the Arkansas school system. The federal judge ruled that the state law was unconstitutional.
His 1996 book on
|
https://en.wikipedia.org/wiki/Creaming
|
Creaming may refer to:
Creaming (chemistry), a process of separation of an emulsion
Creaming (food), several different culinary processes
See also
Cream (disambiguation)
|
https://en.wikipedia.org/wiki/Symmetric%20polynomial
|
In mathematics, a symmetric polynomial is a polynomial in variables, such that if any of the variables are interchanged, one obtains the same polynomial. Formally, is a symmetric polynomial if for any permutation of the subscripts one has .
Symmetric polynomials arise naturally in the study of the relation between the roots of a polynomial in one variable and its coefficients, since the coefficients can be given by polynomial expressions in the roots, and all roots play a similar role in this setting. From this point of view the elementary symmetric polynomials are the most fundamental symmetric polynomials. Indeed, a theorem called the fundamental theorem of symmetric polynomials states that any symmetric polynomial can be expressed in terms of elementary symmetric polynomials. This implies that every symmetric polynomial expression in the roots of a monic polynomial can alternatively be given as a polynomial expression in the coefficients of the polynomial.
Symmetric polynomials also form an interesting structure by themselves, independently of any relation to the roots of a polynomial. In this context other collections of specific symmetric polynomials, such as complete homogeneous, power sum, and Schur polynomials play important roles alongside the elementary ones. The resulting structures, and in particular the ring of symmetric functions, are of great importance in combinatorics and in representation theory.
Examples
The following polynomials in two variables X
|
https://en.wikipedia.org/wiki/IEP
|
IEP may refer to:
Science and technology
Immunoelectrophoresis, biochemistry method
Inclusion–exclusion principle, in the mathematics branch of combinatorics
Integrated electric propulsion, in marine propulsion
Isoelectric point, the pH where a molecule is electrically neutral
Education and research
Individualized Education Program, in the United States, for children with disabilities
Instituts d'études politiques (Institutes of Political Studies), higher education institutions in France
Institute for Economics and Peace, a think tank
Institute for European Politics, a Berlin research centre
Institute for Political Studies – Catholic University of Portugal ()
Internet Encyclopedia of Philosophy
Other uses
Icahn Enterprises, an American conglomerate
Independent Expert Panel, concerned with misconduct by members of the UK parliament
Institute of Employability Professionals, a British professional association
Intercity Express Programme, a British rail transport initiative
Irish pound, the pre-euro currency of Ireland
|
https://en.wikipedia.org/wiki/The%20Absent-Minded%20Professor
|
The Absent-Minded Professor is a 1961 American science fiction comedy film directed by Robert Stevenson and produced by Walt Disney Productions. It is based on the 1943 short story "A Situation of Gravity" by Samuel W. Taylor. The title character was based in part on Hubert Alyea, a professor emeritus of chemistry at Princeton University, who was known as "Dr. Boom" for his explosive demonstrations. The film stars Fred MacMurray as Professor Ned Brainard, alongside Nancy Olson, Keenan Wynn, Tommy Kirk, Leon Ames, Elliott Reid, and Edward Andrews. The plot follows Brainard as he invents a substance that defies gravity, which he later exploits through various means.
Released on March 16, 1961, the film was a huge success at the box office, and two years later became the first Disney film to have a sequel, Son of Flubber (1963). It was one of the first Disney films to be colorized (for the 1986 VHS release), and, along with The Shaggy Dog (1959) and Son of Flubber, is one of Disney's few black-and-white films to be produced after 1941. A remake titled Flubber with Robin Williams was released in 1997.
Plot
Professor Ned Brainard is an absent-minded professor of physical chemistry at Medfield College who invents a substance that gains energy when it strikes a hard surface. This discovery follows some blackboard scribbling in which he reverses a sign in the equation for enthalpy to energy plus pressure times volume. Professor Brainard names his discovery Flubber, a portmanteau of
|
https://en.wikipedia.org/wiki/Isotope%20geochemistry
|
Isotope geochemistry is an aspect of geology based upon the study of natural variations in the relative abundances of isotopes of various elements. Variations in isotopic abundance are measured by isotope ratio mass spectrometry, and can reveal information about the ages and origins of rock, air or water bodies, or processes of mixing between them.
Stable isotope geochemistry is largely concerned with isotopic variations arising from mass-dependent isotope fractionation, whereas radiogenic isotope geochemistry is concerned with the products of natural radioactivity.
Stable isotope geochemistry
For most stable isotopes, the magnitude of fractionation from kinetic and equilibrium fractionation is very small; for this reason, enrichments are typically reported in "per mil" (‰, parts per thousand). These enrichments (δ) represent the ratio of heavy isotope to light isotope in the sample over the ratio of a standard. That is,
‰
Hydrogen
Carbon
Carbon has two stable isotopes, 12C and 13C, and one radioactive isotope, 14C.
The stable carbon isotope ratio, δ13C, is measured against Vienna Pee Dee Belemnite (VPDB). The stable carbon isotopes are fractionated primarily by photosynthesis (Faure, 2004). The 13C/12C ratio is also an indicator of paleoclimate: a change in the ratio in the remains of plants indicates a change in the amount of photosynthetic activity, and thus in how favorable the environment was for the plants. During photosynthesis, organisms using the C3 pathw
|
https://en.wikipedia.org/wiki/Second%20to%20None
|
Second to None may refer to:
2nd to None, a 2003 album by Elvis Presley
Second to None (Chemistry album), a 2003 album by Chemistry
Second to None (film), a 1927 British silent war film
"Second to None", a song by Styles of Beyond, featuring Mike Shinoda of Linkin Park and Fort Minor, from the albums Transformers: The Album (2007) and Reseda Beach (2012)
Second to None, a marching song of the II Corps
|
https://en.wikipedia.org/wiki/Elementary%20symmetric%20polynomial
|
In mathematics, specifically in commutative algebra, the elementary symmetric polynomials are one type of basic building block for symmetric polynomials, in the sense that any symmetric polynomial can be expressed as a polynomial in elementary symmetric polynomials. That is, any symmetric polynomial is given by an expression involving only additions and multiplication of constants and elementary symmetric polynomials. There is one elementary symmetric polynomial of degree in variables for each positive integer , and it is formed by adding together all distinct products of distinct variables.
Definition
The elementary symmetric polynomials in variables , written for , are defined by
and so forth, ending with
In general, for we define
so that if .
(Sometimes, is included among the elementary symmetric polynomials, but excluding it allows generally simpler formulation of results and properties.)
Thus, for each positive integer less than or equal to there exists exactly one elementary symmetric polynomial of degree in variables. To form the one that has degree , we take the sum of all products of -subsets of the variables. (By contrast, if one performs the same operation using multisets of variables, that is, taking variables with repetition, one arrives at the complete homogeneous symmetric polynomials.)
Given an integer partition (that is, a finite non-increasing sequence of positive integers) , one defines the symmetric polynomial , also called an ele
|
https://en.wikipedia.org/wiki/Saul%20Perlmutter
|
Saul Perlmutter (born September 22, 1959) is a U.S. astrophysicist, a professor of physics at the University of California, Berkeley, where he holds the Franklin W. and Karen Weber Dabby Chair, and head of the International Supernova Cosmology Project at the Lawrence Berkeley National Laboratory. He is a member of both the American Academy of Arts & Sciences and the American Philosophical Society, and was elected a Fellow of the American Association for the Advancement of Science in 2003. He is also a member of the National Academy of Sciences. Perlmutter shared the 2006 Shaw Prize in Astronomy, the 2011 Nobel Prize in Physics, and the 2015 Breakthrough Prize in Fundamental Physics with Brian P. Schmidt and Adam Riess for providing evidence that the expansion of the universe is accelerating. Since 2021, he has been a member of the President’s Council of Advisors on Science and Technology (PCAST).
Education
Saul Perlmutter was born one of three children in the Ashkenazi Jewish family of Daniel D. Perlmutter, professor emeritus of chemical and biomolecular engineering at University of Pennsylvania, and Felice (Feige) D. Perlmutter (née Davidson), professor emerita of Temple University’s School of Social Administration. His maternal grandfather, the Yiddish teacher Samuel Davidson (1903–1989), emigrated to Canada (and then with his wife Chaika Newman to New York) from the Bessarabian town of Floreşti in 1919.
Perlmutter spent his childhood in the Mount Airy neighborhood of Ph
|
https://en.wikipedia.org/wiki/Hans%20Peter%20J%C3%B8rgen%20Julius%20Thomsen
|
Hans Peter Jørgen Julius Thomsen (16 February 1826 – 13 February 1909) was a Danish chemist noted in thermochemistry for the Thomsen–Berthelot principle.
Life and work
Thomsen was born in Copenhagen, and spent his life in that city. From 1847 to 1856 he taught chemistry at the Polytechnic, where from 1883 to 1892 he was the director. From 1856 to 1866 he was on the staff of the military high school. In 1866 he was appointed professor of chemistry at the university, and retained that chair until his retirement from active work in 1891.
A friend and colleague of Ludwig A. Colding, who was one of the early advocates of the principle of conservation of energy, Thomsen did much to found the field of thermochemistry. In particular, between 1869 and 1882, he carried out a great number of determinations of the heat evolved or absorbed in chemical reactions, such as the formation of salts, oxidation and reduction, and the combustion of organic compounds. His collected results were published from 1882 to 1886 in four volumes under the title , and also a resume in English under the title "Thermochemistry" in 1908. In 1857 he established in Copenhagen a process for manufacturing soda from cryolite, obtained from the west coast of Greenland. Although his efforts at determining the structure of benzene were unsuccessful, the Thomsen graph in mathematical graph theory is named after him, from an 1886 paper in which he proposed a benzene structure based on this graph.
Thomsen was electe
|
https://en.wikipedia.org/wiki/Triangulation%20%28topology%29
|
In mathematics, triangulation describes the replacement of topological spaces by piecewise linear spaces, i.e. the choice of a homeomorphism in a suitable simplicial complex. Spaces being homeomorphic to a simplicial complex are called triangulable. Triangulation has various uses in different branches of mathematics, for instance in algebraic topology, in complex analysis or in modeling.
Motivation
On the one hand, it is sometimes useful to forget about superfluous information of topological spaces: The replacement of the original spaces with simplicial complexes may help to recognize crucial properties and to gain a better understanding of the considered object.
On the other hand, simplicial complexes are objects of combinatorial character and therefore one can assign them quantities rising from their combinatorial pattern, for instance, the Euler characteristic. Triangulation allows now to assign such quantities to topological spaces.
Investigations concerning the existence and uniqueness of triangulations established a new branch in topology, namely the piecewise-linear-topology (short PL- topology). Its main purpose is topological properties of simplicial complexes and its generalization, cell-complexes.
Simplicial complexes
Abstract simplicial complexes
An abstract simplicial complex above a set is a system of non-empty subsets such that:
for each ;
if and .
The elements of are called simplices, the elements of are called vertices. A simplex with ver
|
https://en.wikipedia.org/wiki/Equilibrium%20point%20%28mathematics%29
|
In mathematics, specifically in differential equations, an equilibrium point is a constant solution to a differential equation.
Formal definition
The point is an equilibrium point for the differential equation
if for all .
Similarly, the point is an equilibrium point (or fixed point) for the difference equation
if for .
Equilibria can be classified by looking at the signs of the eigenvalues of the linearization of the equations about the equilibria. That is to say, by evaluating the Jacobian matrix at each of the equilibrium points of the system, and then finding the resulting eigenvalues, the equilibria can be categorized. Then the behavior of the system in the neighborhood of each equilibrium point can be qualitatively determined, (or even quantitatively determined, in some instances), by finding the eigenvector(s) associated with each eigenvalue.
An equilibrium point is hyperbolic if none of the eigenvalues have zero real part. If all eigenvalues have negative real parts, the point is stable. If at least one has a positive real part, the point is unstable. If at least one eigenvalue has negative real part and at least one has positive real part, the equilibrium is a saddle point and it is unstable. If all the eigenvalues are real and have the same sign the point is called a node.
See also
Autonomous equation
Critical point
Steady state
References
Further reading
Stability theory
Dynamical systems
|
https://en.wikipedia.org/wiki/Object%20theory
|
Object theory can refer to
The object of a metatheory.
The branch of metaphysics also known as abstract object theory.
|
https://en.wikipedia.org/wiki/Dual%20representation
|
In mathematics, if is a group and is a linear representation of it on the vector space , then the dual representation is defined over the dual vector space as follows:
is the transpose of , that is, = for all .
The dual representation is also known as the contragradient representation.
If is a Lie algebra and is a representation of it on the vector space , then the dual representation is defined over the dual vector space as follows:
= for all .
The motivation for this definition is that Lie algebra representation associated to the dual of a Lie group representation is computed by the above formula. But the definition of the dual of a Lie algebra representation makes sense even if it does not come from a Lie group representation.
In both cases, the dual representation is a representation in the usual sense.
Properties
Irreducibility and second dual
If a (finite-dimensional) representation is irreducible, then the dual representation is also irreducible—but not necessarily isomorphic to the original representation. On the other hand, the dual of the dual of any representation is isomorphic to the original representation.
Unitary representations
Consider a unitary representation of a group , and let us work in an orthonormal basis. Thus, maps into the group of unitary matrices. Then the abstract transpose in the definition of the dual representation may be identified with the ordinary matrix transpose. Since the adjoint of a matrix is the complex conjug
|
https://en.wikipedia.org/wiki/Complex%20conjugate%20of%20a%20vector%20space
|
In mathematics, the complex conjugate of a complex vector space is a complex vector space , which has the same elements and additive group structure as but whose scalar multiplication involves conjugation of the scalars. In other words, the scalar multiplication of satisfies
where is the scalar multiplication of and is the scalar multiplication of
The letter stands for a vector in is a complex number, and denotes the complex conjugate of
More concretely, the complex conjugate vector space is the same underlying vector space (same set of points, same vector addition and real scalar multiplication) with the conjugate linear complex structure (different multiplication by ).
Motivation
If and are complex vector spaces, a function is antilinear if
With the use of the conjugate vector space , an antilinear map can be regarded as an ordinary linear map of type The linearity is checked by noting:
Conversely, any linear map defined on gives rise to an antilinear map on
This is the same underlying principle as in defining opposite ring so that a right -module can be regarded as a left -module, or that of an opposite category so that a contravariant functor can be regarded as an ordinary functor of type
Complex conjugation functor
A linear map gives rise to a corresponding linear map which has the same action as Note that preserves scalar multiplication because
Thus, complex conjugation and define a functor from the category of complex vector spaces
|
https://en.wikipedia.org/wiki/Complex%20conjugate%20representation
|
In mathematics, if is a group and is a representation of it over the complex vector space , then the complex conjugate representation is defined over the complex conjugate vector space as follows:
is the conjugate of for all in .
is also a representation, as one may check explicitly.
If is a real Lie algebra and is a representation of it over the vector space , then the conjugate representation is defined over the conjugate vector space as follows:
is the conjugate of for all in .
is also a representation, as one may check explicitly.
If two real Lie algebras have the same complexification, and we have a complex representation of the complexified Lie algebra, their conjugate representations are still going to be different. See spinor for some examples associated with spinor representations of the spin groups and .
If is a *-Lie algebra (a complex Lie algebra with a * operation which is compatible with the Lie bracket),
is the conjugate of for all in
For a finite-dimensional unitary representation, the dual representation and the conjugate representation coincide. This also holds for pseudounitary representations.
See also
Dual representation
Notes
Representation theory of groups
|
https://en.wikipedia.org/wiki/Dave%20Bayer
|
David Allen Bayer (born November 29, 1955) is an American mathematician known for his contributions in algebra and symbolic computation and for his consulting work in the movie industry. He is a professor of mathematics at Barnard College, Columbia University.
Education and career
Bayer was educated at Swarthmore College as an undergraduate, where he attended a course on combinatorial algorithms given by Herbert Wilf. During that semester, Bayer related several original ideas to Wilf on the subject. These contributions were later incorporated into the second edition of Wilf and Albert Nijenhuis' influential book Combinatorial Algorithms, with a detailed acknowledgement by its authors. Bayer subsequently earned his Ph.D. at Harvard University in 1982 under the direction of Heisuke Hironaka with a dissertation entitled The Division Algorithm and the Hilbert Scheme. He joined Columbia University thereafter.
Bayer is the son of Joan and Bryce Bayer, the inventor of the Bayer filter.
Contributions
Bayer has worked in various areas of algebra and symbolic computation, including Hilbert functions, Betti numbers, and linear programming. He has written a number of highly cited papers in these areas with other notable mathematicians, including Bernd Sturmfels, Jeffrey Lagarias, Persi Diaconis, Irena Peeva, and David Eisenbud. Bayer is one of ten individuals cited in the white paper published by the pseudonymous Satoshi Nakamoto describing the technological underpinnings of Bitcoin.
|
https://en.wikipedia.org/wiki/Melissa%20Franklin
|
Melissa Eve Bronwen Franklin (born September 30, 1956) is a Canadian experimental particle physicist and the Mallinckrodt Professor of Physics at Harvard University. In 1992, Franklin became the first woman to receive tenure in the physics department at Harvard University and she served as chair of the department from 2010 to 2014. While working at Fermi National Accelerator Laboratory in Chicago, her team found some of the first evidences for the existence of the top quark. In 1993, Franklin was elected a fellow of the American Physical Society. She is currently member of the CDF (Fermilab) and ATLAS (CERN) collaborations.
Early life and education
Franklin was born in Edmonton, Alberta and grew up first in Vancouver, British Columbia and then Toronto, Ontario, where her family moved in 1962. Her father, Stephen Franklin, was a British-born journalist who worked as drama critic for the Ottawa Journal and later as staff writer and editor for Weekend magazine. Her mother, Elsa, was a television producer as well as Canadian author Pierre Berton's manager and literary agent. Melissa Franklin dropped out of high school to form an alternative school with friends, SEED Alternative School, and later attended the Lycee Francais Charles de Gaulle in London. She took courses in physics, religious studies and philosophy at the University of Toronto, graduating with a bachelor of science in 1977. In the summer of 1975 and 1976, she was a summer research associate at the University of Tor
|
https://en.wikipedia.org/wiki/Environmental%20technology
|
Environmental technology (envirotech) or green technology (greentech), also known as clean technology (cleantech), is the application of one or more of environmental science, green chemistry, environmental monitoring and electronic devices to monitor, model and conserve the natural environment and resources, and to curb the negative impacts of human involvement.
The term is also used to describe sustainable energy generation technologies such as photovoltaics, wind turbines, etc. Sustainable development is the core of environmental technologies. The term environmental technologies is also used to describe a class of electronic devices that can promote sustainable management of resources.
Purification and waste management
Examples
Biofiltration
Bioreactor
Bioremediation
Desalination
Thermal depolymerization
Composting toilet
Pyrolysis
Water purification
Water purification: The whole idea/concept of having dirt/germ/pollution free water flowing throughout the environment. Many other phenomena lead from this concept of purification of water. Water pollution is the main enemy of this concept, and various campaigns and activists have been organized around the world to help purify water.
Air purification
Air purification: Basic and common green plants can be grown indoors to keep the air fresh because all plants remove CO2 and convert it into oxygen. The best examples are: Dypsis lutescens, Sansevieria trifasciata, and Epipremnum aureum. Besides using the plants themselves
|
https://en.wikipedia.org/wiki/Natterer
|
Natterer may refer to:
People
Christian Natterer (born 1981), German politician
August Natterer (1868–1933), German artist
Frank Natterer (born 1941), German mathematics professor
Johann Natterer (1787–1843), Austrian explorer and naturalist
Other
Natterer's bat, Myotis nattereri
|
https://en.wikipedia.org/wiki/Jorhat%20Engineering%20College
|
Jorhat Engineering College founded in 1960 by the Government of Assam, is a government engineering college in Assam, northeast India. The college, affiliated with Assam Science and Technology University, is accredited by the All India Council for Technical Education. It has five four-year undergraduate programs: Civil Engineering, Computer Science and Engineering, Electrical Engineering, Instrumentation and Mechanical Engineering. It also offers master's courses in Computer Application (MCA), Civil Engineering (Design of Civil Engineering Structures) Electrical Engineering (Instrumentation and control engineering). It also offers PhD courses.
History
Jorhat Engineering College, the second Government Engineering Institute of Assam came into existence on 7 January 1959 at H.R.H.P.O.W. Institute of Engineering & Technology, Jorhat with the then Principal of the institute, Sri H.N. Barua also as the Principal in-charge of Jorhat Engineering College. The College started functioning with admission of its first batch of students in Civil Engineering, on 10 October 1960.
Academics
The college offers a three-year, postgraduate Master of Computer Applications program for 30 students per year. Its Department of Civil Engineering offers a four-year course leading to a Bachelor of Engineering (B.E) degree for 75 students per year. Established in 1961, the Department of Mechanical Engineering has an intake capacity of 90 students per year. It covers the design, physics and theory of mech
|
https://en.wikipedia.org/wiki/Cristovam%20Buarque
|
Cristovam Ricardo Cavalcanti Buarque (; born February 20, 1944) is a Brazilian university professor and member of Cidadania. He was a senator for the Federal District from 2003 to 2019.
Biography
Buarque graduated in mechanical engineering from the Federal University of Pernambuco in 1966. At that time he engaged in student politics becoming a militant of the Ação Popular, a group of the Leftist Progressive Church. After the 1964 coup, he was persecuted and exiled to France, where he earned a PhD in economics from the Pantheon-Sorbonne University, Paris, in 1973. He worked at Inter-American Development Bank (IDB) in Ecuador, Honduras, and the United States from 1973–79. He was the first elected rector, by direct vote, of the University of Brasilia in the wake of the military regime; governor of the Federal District; Minister of Education; and current senator, who was elected by a landslide vote. He worked as a consultant for several national and international bodies under the United Nations (UN) and presided over the University for Peace Council and participated in the Food Presidential Commission, which was formerly directed by late sociologist Herbert "Betinho" de Souza.
Buarque is a member of UNESCO's Institute of Education and of the Council of the United Nations University. He initiated the NGO Mission Child, which sponsors an income transfer program for thousands of families and is funded by private enterprises. He was awarded the Jabuti prize of Literature in 1995. H
|
https://en.wikipedia.org/wiki/PTAS
|
PTAS or Ptas may refer to:
Polynomial-time approximation scheme, an approximation algorithm in computer science
Pesetas, Spanish currency
PTAS reduction, an approximation-preserving reduction in computational complexity theory
Preferential trading area, another term for a trade bloc
See also
PTA (disambiguation)
|
https://en.wikipedia.org/wiki/Extensible%20programming
|
Extensible programming is a term used in computer science to describe a style of computer programming that focuses on mechanisms to extend the programming language, compiler and runtime environment. Extensible programming languages, supporting this style of programming, were an active area of work in the 1960s, but the movement was marginalized in the 1970s. Extensible programming has become a topic of renewed interest in the 21st century.
Historical movement
The first paper usually associated with the extensible programming language movement is M. Douglas McIlroy's 1960 paper on macros for higher-level programming languages. Another early description of the principle of extensibility occurs in Brooker and Morris's 1960 paper on the Compiler-Compiler. The peak of the movement was marked by two academic symposia, in 1969 and 1971. By 1975, a survey article on the movement by Thomas A. Standish was essentially a post mortem. The Forth programming language was an exception, but it went essentially unnoticed.
Character of the historical movement
As typically envisioned, an extensible programming language consisted of a base language providing elementary computing facilities, and a meta-language capable of modifying the base language. A program then consisted of meta-language modifications and code in the modified base language.
The most prominent language-extension technique used in the movement was macro definition. Grammar modification was also closely associated wi
|
https://en.wikipedia.org/wiki/Nina%20Byers
|
Nina Byers (January 19, 1930 – June 5, 2014) was a theoretical physicist, research professor and professor of physics emeritus in the department of physics and astronomy, UCLA, and Fellow of Somerville College, Oxford.
Contributions
Byers received a B.A. from the University of California, Berkeley in 1950 and a Ph.D. from the University of Chicago in 1956.
Byers made phenomenological analyses of experimental observations leading to theoretical advances in particle physics and the theory of superconductivity. In "Theoretical considerations concerning quantized magnetic flux in superconductors," she showed that observation of flux quantization in superconductors in units of hc/2e is experimental evidence for the Cooper pairing of electrons proposed by the BCS theory of superconductivity (Byers-Yang theorem).
In addition to scientific papers, Byers published papers and edited a book on original and important contributions to modern physics by 20th century female physicists. She developed the website Contributions of 20th Century Women to Physics (CWP website), which documents original and important contributions to physics by over 80 female physicists of the 20th century. With Gary Williams, she edited a book based on data from the website that expands the biographies and describes more fully the scientific contributions of forty distinguished 20th century female physicists.
Byers was elected to many offices in The American Physical Society (APS) and American Association for
|
https://en.wikipedia.org/wiki/Thaddeus%20S.%20C.%20Lowe
|
Thaddeus Sobieski Constantine Lowe (August 20, 1832 – January 16, 1913), also known as Professor T. S. C. Lowe, was an American Civil War aeronaut, scientist and inventor, mostly self-educated in the fields of chemistry, meteorology, and aeronautics, and the father of military aerial reconnaissance in the United States. By the late 1850s he was well known for his advanced theories in the meteorological sciences as well as his balloon building. Among his aspirations were plans for a transatlantic flight.
Lowe's scientific endeavors were cut short by the onset of the American Civil War, for which he offered his services performing aerial reconnaissance on the Confederate troops for the Union Army. In July 1861 Lowe was appointed Chief Aeronaut of the Union Army Balloon Corps by President Abraham Lincoln. Though his work was generally successful, it was not fully appreciated by all members of the military, and disputes over his operations and pay scale forced him to resign in 1863. Lowe returned to the private sector and continued his scientific exploration of hydrogen gas manufacturing. He invented the water gas process by which large amounts of hydrogen gas could be produced from steam and coke. His inventions and patents on this process and ice making machines made him a millionaire.
In 1887 he moved to Los Angeles, California, and eventually built a 24,000 sq. ft. (2,230 m2) home in Pasadena. He opened several ice-making plants and founded Citizen's Bank of Los Angeles. Lo
|
https://en.wikipedia.org/wiki/Bessel%27s%20inequality
|
In mathematics, especially functional analysis, Bessel's inequality is a statement about the coefficients of an element in a Hilbert space with respect to an orthonormal sequence. The inequality was derived by F.W. Bessel in 1828.
Let be a Hilbert space, and suppose that is an orthonormal sequence in . Then, for any in one has
where ⟨·,·⟩ denotes the inner product in the Hilbert space . If we define the infinite sum
consisting of "infinite sum" of vector resolute in direction , Bessel's inequality tells us that this series converges. One can think of it that there exists that can be described in terms of potential basis .
For a complete orthonormal sequence (that is, for an orthonormal sequence that is a basis), we have Parseval's identity, which replaces the inequality with an equality (and consequently with ).
Bessel's inequality follows from the identity
which holds for any natural n.
See also
Cauchy–Schwarz inequality
Parseval's theorem
References
External links
Bessel's Inequality the article on Bessel's Inequality on MathWorld.
Hilbert spaces
Inequalities
|
https://en.wikipedia.org/wiki/Regnier%20de%20Graaf
|
Regnier de Graaf (English spelling), original Dutch spelling Reinier de Graaf, or Latinized Reijnerus de Graeff (30 July 164117 August 1673), was a Dutch physician, physiologist and anatomist who made key discoveries in reproductive biology. He specialized in iatrochemistry and iatrogenesis, and was the first to develop a syringe to inject dye into human reproductive organs so that he could understand their structure and function.
Biography
De Graaf was born in Schoonhoven as the son of an carpenter/engineer or architect and studied medicine in Leuven (1658), Utrecht and Leiden (1663). There his co-students were Jan Swammerdam, Niels Stensen, Ole Borch and Frederik Ruysch, cooperating with professor Franciscus Sylvius, Johannes van Horne and Lucas Schacht. All of them were interested in the organs of procreation and influenced by Rene Descartes' iatrophysical approach. He submitted his doctoral thesis on the pancreas, and in 1665 he went (together with his brother) to France where he further experimented on dogs, cooperating with Pierre Bourdelot. He obtained his medical degree from the University of Angers with Jean Chapelain as his translator. Back in the Dutch Republic, De Graaf established himself at Oude Delft. He was studying the male genitalia, which led to a publication in 1668. For his research in the anatomical theatre on the ovarian follicle he used female rabbits. (The dissection of corpses was only done in winter, and cadavers were scarce; most were sent to L
|
https://en.wikipedia.org/wiki/Ewens%27s%20sampling%20formula
|
In population genetics, Ewens's sampling formula, describes the probabilities associated with counts of how many different alleles are observed a given number of times in the sample.
Definition
Ewens's sampling formula, introduced by Warren Ewens, states that under certain conditions (specified below), if a random sample of n gametes is taken from a population and classified according to the gene at a particular locus then the probability that there are a1 alleles represented once in the sample, and a2 alleles represented twice, and so on, is
for some positive number θ representing the population mutation rate, whenever is a sequence of nonnegative integers such that
The phrase "under certain conditions" used above is made precise by the following assumptions:
The sample size n is small by comparison to the size of the whole population; and
The population is in statistical equilibrium under mutation and genetic drift and the role of selection at the locus in question is negligible; and
Every mutant allele is novel.
This is a probability distribution on the set of all partitions of the integer n. Among probabilists and statisticians it is often called the multivariate Ewens distribution.
Mathematical properties
When θ = 0, the probability is 1 that all n genes are the same. When θ = 1, then the distribution is precisely that of the integer partition induced by a uniformly distributed random permutation. As θ → ∞, the probability that no two of the n genes are the sam
|
https://en.wikipedia.org/wiki/Diatonic%20set%20theory
|
Diatonic set theory is a subdivision or application of musical set theory which applies the techniques and analysis of discrete mathematics to properties of the diatonic collection such as maximal evenness, Myhill's property, well formedness, the deep scale property, cardinality equals variety, and structure implies multiplicity. The name is something of a misnomer as the concepts involved usually apply much more generally, to any periodically repeating scale.
Music theorists working in diatonic set theory include Eytan Agmon, Gerald J. Balzano, Norman Carey, David Clampitt, John Clough, Jay Rahn, and mathematician Jack Douthett. A number of key concepts were first formulated by David Rothenberg (the Rothenberg propriety), who published in the journal Mathematical Systems Theory, and Erv Wilson, working entirely outside of the academic world.
See also
Bisector
Diatonic and chromatic
Generic and specific intervals
Further reading
Balzano, Gerald, "The Pitch Set as a Level of Description for Studying Musical Pitch Perception", Music, Mind and Brain, the Neurophysiology of Music, Manfred Clynes, ed., Plenum Press, 1982.
Carey, Norman and Clampitt, David (1996), "Self-Similar Pitch Structures, Their Duals, and Rhythmic Analogues", Perspectives of New Music 34, no. 2: 62–87.
Grady, Kraig, (2007), "An Introduction to the Moments of Symmetry", Wilson Archives, anaphoria.com
Johnson, Timothy (2003), Foundations of Diatonic Theory: A Mathematically Based Approach to Music Fundament
|
https://en.wikipedia.org/wiki/T-7%20%28rocket%29
|
The T-7 was China's first sounding rocket. A test rocket, dubbed the T-7M, was first successfully launched on 19 February 1960 in Nanhui, Shanghai, and a full-scale rocket was launched on 13 September 1960. Wang Xiji of the Shanghai Institute of Mechanical and Electrical Engineering was the chief designer. Twenty-four T-7 rockets were launched between 1960 and 1965, and it was retired after a final launch in 1969.
Specifications
The T-7 was designed to carry a payload of to an altitude of . It had a length of , a launch weight of and a diameter of .
History
In 1958, China started its satellite program and tasked the Shanghai Institute of Mechanical and Electrical Engineering with the development of rockets for satellite launches. Wang Xiji, a professor of the Department of Engineering Mechanics at Shanghai Jiao Tong University, was appointed the chief engineer in charge of the rocket development, and was appointed deputy director of the institute in charge of the overall program including the launch site.
The institute had very few experienced scientists. Other than Wang and Yang, there were only two visiting professors, Bian Yingui () and Li Minhua. The rest of the institute consisted of a few hundred university students with an average age of 21. Even Wang and Yang had little knowledge about rockets and had to learn on the fly.
The development team worked with severe shortages of technical experience, funds, and equipment. They often worked in hunger as China was in
|
https://en.wikipedia.org/wiki/A1C
|
A1C may refer to:
Biology and chemistry
Glycated hemoglobin (hemoglobin A1c or HbA1c), a surrogate marker for blood glucose levels
A1C recepter, the alpha-1C adrenergic receptor
Transportation and vehicles
Rivian A1C, a prototype CUV, predecessor of the Rivian R1S
MV (A1C) William H. Pitsenbarger, U.S. maritime sealift command container ship
NASA A1C spacesuit, an Apollo variant of the Gemini spacesuit
Other uses
Airman First Class, the third enlisted rank in the United States Air Force
A1C, a postal code occurring in Downtown St. John's, Newfoundland Island, Newfoundland and Labrador, Canada
See also
AIC (disambiguation)
ALC (disambiguation)
|
https://en.wikipedia.org/wiki/Robert%20S.%20Barton
|
Robert Stanley "Bob" Barton (February 13, 1925 – January 28, 2009) was the chief architect of the Burroughs B5000 and other computers such as the B1700, a co-inventor of dataflow architecture, and an influential professor at the University of Utah.
His students at Utah have had a large role in the development of computer science.
Barton designed machines at a more abstract level, not tied to the technology constraints of the time. He employed high-level languages and a stack machine in his design of the B5000 computer. Its design survives in the modern Unisys ClearPath MCP systems. His work with stack machine architectures was the first implementation in a mainframe computer.
Barton died on January 28, 2009, in Portland, Oregon, aged 83.
Career
Barton was born in New Britain, Connecticut in 1925 and received his BA in 1948, and his MS in 1949 in Mathematics, from the University of Iowa. His early experience with computers was when he worked in the IBM Applied Science Department in 1951.
In 1954, he joined the Shell Oil Company Technical Services, working on programming applications. He worked at Shell Development, a research group in Texas where he worked with a Burroughs/Datatron 205 computer. In 1958, he studied Irving Copi and Jan Łukasiewicz's work on symbolic logic and Polish notation, and considered its application to arithmetic expression processing on a computer.
Barton joined Burroughs Corporation, ElectroData Division, in Pasadena, California in the late 1950
|
https://en.wikipedia.org/wiki/Samir%20Khader
|
Samir Khader is the Head of Programs and Current Affairs at Sky News Arabia, after having been the Program Editor & Head of Output of Qatar-based broadcaster Al Jazeera. He comes from Jordan. He has degrees in journalism and mathematics from universities in Grenoble and Paris. Samir Khader began his career as a TV journalist in 1979 on French television. He worked for many years in Jordan as a journalist in television news before joining Al Jazeera and then Sky News Arabia in Abu Dhabi. He is well known for being featured in the documentary film Control Room, when he was a senior producer.
Quotes
"Between us, if I am offered a job with FOX NEWS, I would take it - to change the arab nightmare into the American dream....I still have that dream."
-Control Room, interview with Samir Khader
References
External links
Counter Currents - Al-Jazeera: Holding The Head High interview with Samir Khader, February 7, 2006
CBC News - Passionate Eye Showcase: Control Room program on the making of the documentary film, September 26, 2004
IPA - Voices That Must Be Heard - Inside Al Jazeera: A Conversation with Samir Khader interview July 1, 2004 issue
In These Times - Inside Al-Jazeera interview June 18, 2004
Philadelphia City Paper - The View From Here interview June 18, 2004
LA Weekly - Meeting Al-Jazeera extensive interview June 4, 2004
Pacifica Radio report and audio
Democracy Now! - Massacre in Fallujah: Over 600 Dead, 1,000 Injured, 60,000 Refugees April 12, 2004 with transcript,
|
https://en.wikipedia.org/wiki/Iterated%20function
|
In mathematics, an iterated function is a function (that is, a function from some set to itself) which is obtained by composing another function with itself a certain number of times. The process of repeatedly applying the same function is called iteration. In this process, starting from some initial object, the result of applying a given function is fed again in the function as input, and this process is repeated. For example on the image on the right:
with the circle‑shaped symbol of function composition.
Iterated functions are objects of study in computer science, fractals, dynamical systems, mathematics and renormalization group physics.
Definition
The formal definition of an iterated function on a set X follows.
Let be a set and be a function.
Defining as the n-th iterate of (a notation introduced by Hans Heinrich Bürmann and John Frederick William Herschel), where n is a non-negative integer, by:
and
where is the identity function on and denotes function composition. That is,
,
always associative.
Because the notation may refer to both iteration (composition) of the function or exponentiation of the function (the latter is commonly used in trigonometry), some mathematicians choose to use to denote the compositional meaning, writing for the -th iterate of the function , as in, for example, meaning . For the same purpose, was used by Benjamin Peirce whereas Alfred Pringsheim and Jules Molk suggested instead.
Abelian property and iteration se
|
https://en.wikipedia.org/wiki/Conjugate%20gradient%20method
|
In mathematics, the conjugate gradient method is an algorithm for the numerical solution of particular systems of linear equations, namely those whose matrix is positive-definite. The conjugate gradient method is often implemented as an iterative algorithm, applicable to sparse systems that are too large to be handled by a direct implementation or other direct methods such as the Cholesky decomposition. Large sparse systems often arise when numerically solving partial differential equations or optimization problems.
The conjugate gradient method can also be used to solve unconstrained optimization problems such as energy minimization. It is commonly attributed to Magnus Hestenes and Eduard Stiefel, who programmed it on the Z4, and extensively researched it.
The biconjugate gradient method provides a generalization to non-symmetric matrices. Various nonlinear conjugate gradient methods seek minima of nonlinear optimization problems.
Description of the problem addressed by conjugate gradients
Suppose we want to solve the system of linear equations
for the vector , where the known matrix is symmetric (i.e., AT = A), positive-definite (i.e. xTAx > 0 for all non-zero vectors in Rn), and real, and is known as well. We denote the unique solution of this system by .
Derivation as a direct method
The conjugate gradient method can be derived from several different perspectives, including specialization of the conjugate direction method for optimization, and variation of the
|
https://en.wikipedia.org/wiki/MAF
|
MAF may refer to:
Military
Myanmar Air Force
Malaysian Armed Forces
Marine Amphibious Force, a former name for Marine Expeditionary Force, a type of U.S. Marine Corps task force
Organizations
Majid Al Futtaim Group
Move America Forward
Mission Aviation Fellowship
Science
MAF (gene)
Minor allele frequency in genetics
Methoxyacetylfentanyl, an opioid analgesic
Macrophage-activating factor
Moisture and Ash Free, a measure of moisture and ash content as used in ranking coals or the heat-content of wood
Million acre-foot, MAF, a unit of volume commonly used in the United States in reference to large-scale water resources
Sports
Malaysia Athletics Federation
Metin-Ali-Feyyaz, Turkish football trio who constituted attacking line of Turkish sports club Beşiktaş J.K.
Marc-André Fleury (born 1984), Canadian ice hockey goaltender in the National Hockey League
Technology
Mass airflow sensor, used to find the mass flowrate of air entering a fuel-injected internal combustion engine
MAFless Tuning, a method of operating the fuel injection system on a gasoline-powered motor vehicle whereby the mass airflow meter is removed
Markranstädter Automobilfabrik, a German car-brand built from 1909 to 1923 in Markranstädt
Mozilla Archive Format, a format for archiving web pages and also an add-on of the same name for Mozilla Firefox
Magnetic field-assisted finishing
Microsoft Access Form, a file format associated with Microsoft Access, bearing the file extension .maf
Other
|
https://en.wikipedia.org/wiki/Digital%20Blasphemy
|
Digital Blasphemy is a commercial website for computer wallpapers designed and created by independent Computer-generated imagery artist Ryan Bliss, an English and Computer Science graduate from the University of Iowa. The name Digital Blasphemy was chosen because of the "Godlike" feeling Bliss experienced when creating worlds through artwork.
The site is subscription-based, but a free gallery is available to non-members. Images in the free gallery are rotated regularly with fresh images, and are presented in various screen resolutions. In addition, the free gallery provides multi-monitor samples and mobile device images for Android devices, as well as BlackBerry, iPhone, and Palm. The member gallery includes all available artwork numbering over 820, not including image alternate forms.
Some images have additional forms and are in a section known as the "Picklejar". This provides the same images in different colors or presentations, or similar images with removed, added, or changed content or elements. At times, the original image ends up in the Picklejar section and the updated and improved image takes its place in the main gallery. A way to browse Pickle Jar images was added in June 2014.
Designs
Typical designs include science fiction and fantasy, space imagery, planetscapes, landscapes, cityscapes, seascapes, underwater scenes, interiors, abstracts, fractals. There are also images depicting seasons and seasonal events, special occasions, and holidays such as Hallowee
|
https://en.wikipedia.org/wiki/Entertainment%20robot
|
An entertainment robot is, as the name indicates, a robot that is not made for utilitarian use, as in production or domestic services, but for the sole subjective pleasure of the human. It serves, usually the owner or his housemates, guests, or clients. Robotic technologies are applied in many areas of culture and entertainment.
Expensive robotics are applied to the creation of narrative environments in commercial venues where servo motors, pneumatics, and hydraulic actuators are used to create movement with often preprogrammed responsive behaviors such as in Disneyland's haunted house ride.
Entertainment robots can also be seen in the context of media arts where artists have been employing advanced technologies to create environments and artistic expression also utilizing actuators and sensors to allow their robots to react and change about viewers.
Toy robot
Relatively cheap, mass-produced entertainment robots are used as mechanical, sometimes interactive, toys that perform various tasks and tricks on command. The first commercial hit was, not surprisingly, modeled on the most popular pet: the canine.
Robotic dog
Robot dogs as a fad have been produced with relatively little variation. These are some commercial models:
Teksta, a toy robot dog popular in the 1990s was intended to be able to perform card tricks and respond to commands.
Aibo (robot dog manufactured by Sony)
Poo-Chi
I-Cybie
iDog (Sega's robot iPod music speaker)
Gupi, a robotic guinea pig
Space Dog,
|
https://en.wikipedia.org/wiki/Bidiagonal%20matrix
|
In mathematics, a bidiagonal matrix is a banded matrix with non-zero entries along the main diagonal and either the diagonal above or the diagonal below. This means there are exactly two non-zero diagonals in the matrix.
When the diagonal above the main diagonal has the non-zero entries the matrix is upper bidiagonal. When the diagonal below the main diagonal has the non-zero entries the matrix is lower bidiagonal.
For example, the following matrix is upper bidiagonal:
and the following matrix is lower bidiagonal:
Usage
One variant of the QR algorithm starts with reducing a general matrix into a bidiagonal one,
and the singular value decomposition (SVD) uses this method as well.
Bidiagonalization
Bidiagonalization allows guaranteed accuracy when using floating-point arithmetic to compute singular values.
See also
List of matrices
LAPACK
Hessenberg form – The Hessenberg form is similar, but has more non-zero diagonal lines than 2.
References
Stewart, G. W. (2001) Matrix Algorithms, Volume II: Eigensystems. Society for Industrial and Applied Mathematics. .
External links
High performance algorithms for reduction to condensed (Hessenberg, tridiagonal, bidiagonal) form
Linear algebra
Sparse matrices
|
https://en.wikipedia.org/wiki/Herb%20Sutter
|
Herb Sutter is a prominent C++ expert. He is also an author of several books on C++ and was a columnist for Dr. Dobb's Journal.
Education and career
Sutter was born and raised in Oakville, Ontario, and studied computer science at Canada's University of Waterloo.
From 1995 to 2001 he was chief technology officer at PeerDirect where he designed the PeerDirect database replication engine.
He joined Microsoft in 2002 as a platform evangelist for Visual C++ .NET, rising to lead software architect for C++/CLI. In recent years Sutter was lead designer for C++/CX and C++ AMP.
Sutter has served as the chair of the ISO C++ standards committee since 2002.
In 2005, Sutter published an article titled "The Free Lunch Is Over" that claimed that microprocessor serial-processing speed was reaching a physical limit leading to two main consequences:
processor manufacturers would focus on products that better support multithreading (such as multi-core processors), and
software developers would be forced to develop massively multithreaded programs as a way to better use such processors.
The article is seen as highly influential in subsequent system design.
Bibliography
Exceptional C++ (Addison-Wesley, 2000, )
More Exceptional C++ (Addison-Wesley, 2002, )
Exceptional C++ Style (Addison-Wesley, 2005, )
C++ Coding Standards (together with Andrei Alexandrescu, Addison-Wesley, 2005, )
References
External links
Living people
Canadian computer programmers
People in information technol
|
https://en.wikipedia.org/wiki/Nick%20Katz
|
Nicholas Michael Katz (born December 7, 1943) is an American mathematician, working in arithmetic geometry, particularly on p-adic methods, monodromy and moduli problems, and number theory. He is currently a professor of Mathematics at Princeton University and an editor of the journal Annals of Mathematics.
Life and work
Katz graduated from Johns Hopkins University (BA 1964) and from Princeton University, where in 1965 he received his master's degree and in 1966 he received his doctorate under supervision of Bernard Dwork with thesis On the Differential Equations Satisfied by Period Matrices. After that, at Princeton, he was an instructor, an assistant professor in 1968, associate professor in 1971 and professor in 1974. From 2002 to 2005 he was the chairman of faculty there. He was also a visiting scholar at the University of Minnesota, the University of Kyoto, Paris VI, Orsay Faculty of Sciences, the Institute for Advanced Study and the IHES. While in France, he adapted methods of scheme theory and category theory to the theory of modular forms. Subsequently, he has applied geometric methods to various exponential sums.
From 1968 to 1969, he was a NATO Postdoctoral Fellow, from 1975 to 1976 and from 1987–1988 Guggenheim Fellow and from 1971 to 1972 Sloan Fellow. In 1970 he was an invited speaker at the International Congress of Mathematicians in Nice (The regularity theorem in algebraic geometry) and in 1978 in Helsinki (p-adic L functions, Serre-Tate local moduli and
|
https://en.wikipedia.org/wiki/Band%20matrix
|
In mathematics, particularly matrix theory, a band matrix or banded matrix is a sparse matrix whose non-zero entries are confined to a diagonal band, comprising the main diagonal and zero or more diagonals on either side.
Band matrix
Bandwidth
Formally, consider an n×n matrix A=(ai,j ). If all matrix elements are zero outside a diagonally bordered band whose range is determined by constants k1 and k2:
then the quantities k1 and k2 are called the and , respectively. The of the matrix is the maximum of k1 and k2; in other words, it is the number k such that if .
Examples
A band matrix with k1 = k2 = 0 is a diagonal matrix
A band matrix with k1 = k2 = 1 is a tridiagonal matrix
For k1 = k2 = 2 one has a pentadiagonal matrix and so on.
Triangular matrices
For k1 = 0, k2 = n−1, one obtains the definition of an upper triangular matrix
similarly, for k1 = n−1, k2 = 0 one obtains a lower triangular matrix.
Upper and lower Hessenberg matrices
Toeplitz matrices when bandwidth is limited.
Block diagonal matrices
Shift matrices and shear matrices
Matrices in Jordan normal form
A skyline matrix, also called "variable band matrix"a generalization of band matrix
The inverses of Lehmer matrices are constant tridiagonal matrices, and are thus band matrices.
Applications
In numerical analysis, matrices from finite element or finite difference problems are often banded. Such matrices can be viewed as descriptions of the coupling between the problem variables; the banded propert
|
https://en.wikipedia.org/wiki/Homologous%20series
|
In organic chemistry, a homologous series is a sequence of compounds with the same functional group and similar chemical properties in which the members of the series can be branched or unbranched, or differ by molecular formula of and molecular mass of 14u. This can be the length of a carbon chain, for example in the straight-chained alkanes (paraffins), or it could be the number of monomers in a homopolymer such as amylose. A homologue (also spelled as homolog) is a compound belonging to a homologous series.
Compounds within a homologous series typically have a fixed set of functional groups that gives them similar chemical and physical properties. (For example, the series of primary straight-chained alcohols has a hydroxyl at the end of the carbon chain.) These properties typically change gradually along the series, and the changes can often be explained by mere differences in molecular size and mass. The name "homologous series" is also often used for any collection of compounds that have similar structures or include the same functional group, such as the general alkanes (straight and branched), the alkenes (olefins), the carbohydrates, etc. However, if the members cannot be arranged in a linear order by a single parameter, the collection may be better called a "chemical family" or "class of homologous compounds" than a "series".
The concept of homologous series was proposed in 1843 by the French chemist Charles Gerhardt. A homologation reaction is a chemical process
|
https://en.wikipedia.org/wiki/Laser%20guidance
|
Laser guidance directs a robotics system to a target position by means of a laser beam. The laser guidance of a robot is accomplished by projecting a laser light, image processing and communication to improve the accuracy of guidance. The key idea is to show goal positions to the robot by laser light projection instead of communicating them numerically. This intuitive interface simplifies directing the robot while the visual feedback improves the positioning accuracy and allows for implicit localization. The guidance system may serve also as a mediator for cooperative multiple robots.
Examples of proof-of-concept experiments of directing a robot by a laser pointer are shown on video.
Laser guidance spans areas of robotics, computer vision, user interface, video games, communication and smart home technologies.
Commercial systems
Samsung Electronics Co., Ltd. may have been using this technology in robotic vacuum cleaners since 2014.
Google Inc. applied for a patent with USPTO on using visual light or laser beam between devices to represent connections and interactions between them (Appl. No. 13/659,493, Pub. No. 2014/0363168).
However, no patent was granted to Google on this application.
Military use
Laser guidance is used by military to guide a missile or other projectile or vehicle to a target by means of a laser beam, either beam riding guidance or semi-active laser homing (SALH). With this technique, a laser is kept pointed at the target and the laser radiation bo
|
https://en.wikipedia.org/wiki/Seth%20Lloyd
|
Seth Lloyd (born August 2, 1960) is a professor of mechanical engineering and physics at the Massachusetts Institute of Technology.
His research area is the interplay of information with complex systems, especially quantum systems. He has performed seminal work in the fields of quantum computation, quantum communication and quantum biology, including proposing the first technologically feasible design for a quantum computer, demonstrating the viability of quantum analog computation, proving quantum analogs of Shannon's noisy channel theorem, and designing novel methods for quantum error correction and noise reduction.
Biography
Lloyd was born on August 2, 1960. He graduated from Phillips Academy in 1978 and received a bachelor of arts degree from Harvard College in 1982. He earned a certificate of advanced study in mathematics and a master of philosophy degree from Cambridge University in 1983 and 1984, while on a Marshall Scholarship. Lloyd was awarded a doctorate by Rockefeller University in 1988 (advisor Heinz Pagels) after submitting a thesis on Black Holes, Demons, and the Loss of Coherence: How Complex Systems Get Information, and What They Do With It.
From 1988 to 1991, Lloyd was a postdoctoral fellow in the High Energy Physics Department at the California Institute of Technology, where he worked with Murray Gell-Mann on applications of information to quantum-mechanical systems. From 1991 to 1994, he was a postdoctoral fellow at Los Alamos National Laboratory, wher
|
https://en.wikipedia.org/wiki/Universal%20graph
|
In mathematics, a universal graph is an infinite graph that contains every finite (or at-most-countable) graph as an induced subgraph. A universal graph of this type was first constructed by Richard Rado and is now called the Rado graph or random graph. More recent work
has focused on universal graphs for a graph family : that is, an infinite graph belonging to F that contains all finite graphs in . For instance, the Henson graphs are universal in this sense for the -clique-free graphs.
A universal graph for a family of graphs can also refer to a member of a sequence of finite graphs that contains all graphs in ; for instance, every finite tree is a subgraph of a sufficiently large hypercube graph
so a hypercube can be said to be a universal graph for trees. However it is not the smallest such graph: it is known that there is a universal graph for -vertex trees, with only vertices and edges, and that this is optimal. A construction based on the planar separator theorem can be used to show that -vertex planar graphs have universal graphs with edges, and that bounded-degree planar graphs have universal graphs with edges. It is also possible to construct universal graphs for planar graphs that have vertices.
Sumner's conjecture states that tournaments are universal for polytrees, in the sense that every tournament with vertices contains every polytree with vertices as a subgraph.
A family of graphs has a universal graph of polynomial size, containing every -vert
|
https://en.wikipedia.org/wiki/Ludwig%20Schl%C3%A4fli
|
Ludwig Schläfli (15 January 1814 – 20 March 1895) was a Swiss mathematician, specialising in geometry and complex analysis (at the time called function theory) who was one of the key figures in developing the notion of higher-dimensional spaces. The concept of multidimensionality is pervasive in mathematics, has come to play a pivotal role in physics, and is a common element in science fiction.
Life and career
Youth and education
Ludwig spent most of his life in Switzerland. He was born in Grasswil (now part of Seeberg), his mother's hometown. The family then moved to the nearby Burgdorf, where his father worked as a tradesman. His father wanted Ludwig to follow in his footsteps, but Ludwig was not cut out for practical work.
In contrast, because of his mathematical gifts, he was allowed to attend the Gymnasium in Bern in 1829. By that time he was already learning differential calculus from Abraham Gotthelf Kästner's Mathematische Anfangsgründe der Analysis des Unendlichen (1761). In 1831 he transferred to the Akademie in Bern for further studies. By 1834 the Akademie had become the new Universität Bern, where he started studying theology.
Teaching
After graduating in 1836, he was appointed a secondary school teacher in Thun. He stayed there until 1847, spending his free time studying mathematics and botany while attending the university in Bern once a week.
A turning point in his life came in 1843. Schläfli had planned to visit Berlin and become acquainted with its math
|
https://en.wikipedia.org/wiki/Clara%20Immerwahr
|
Clara Helene Immerwahr (; 21 June 1870 – 2 May 1915) was a German chemist. She was the first German woman to be awarded a doctorate in chemistry from the University of Breslau, and is credited with being a pacifist as well as a "heroine of the women's rights movement". From 1901 until her suicide in 1915, she was married to the Nobel Prize-winning chemist Fritz Haber.
Early life and education
Immerwahr was born on the Polkendorff Farm near Breslau (then in eastern Prussia; now known as Wojczyce, in western Poland). She was the youngest daughter of Jewish parents, chemist Philipp Immerwahr and his wife Anna (née Krohn). She grew up on the farm with her three older siblings, Elli, Rose and Paul. In 1890, her mother died of cancer; while Elli and her husband Siegfried stayed at the farm, Clara moved with her father to Breslau.
Immerwahr studied at the University of Breslau, attaining her degree and a PhD in chemistry under Richard Abegg in 1900, after 8 semesters of study (two more than required for male doctoral candidates). Her dissertation was entitled (Contributions to the Solubility of Slightly Soluble Salts of Mercury, Copper, Lead, Cadmium, and Zinc). She was the first woman Ph.D. at the University of Breslau and received the designation magna cum laude. Her thesis defense was held in the main hall of the university and was attended by many young women of the city, interested in seeing "" ("our first female doctor"). A few months after obtaining her degree, she gave a
|
https://en.wikipedia.org/wiki/Hankel%20transform
|
In mathematics, the Hankel transform expresses any given function f(r) as the weighted sum of an infinite number of Bessel functions of the first kind . The Bessel functions in the sum are all of the same order ν, but differ in a scaling factor k along the r axis. The necessary coefficient of each Bessel function in the sum, as a function of the scaling factor k constitutes the transformed function. The Hankel transform is an integral transform and was first developed by the mathematician Hermann Hankel. It is also known as the Fourier–Bessel transform. Just as the Fourier transform for an infinite interval is related to the Fourier series over a finite interval, so the Hankel transform over an infinite interval is related to the Fourier–Bessel series over a finite interval.
Definition
The Hankel transform of order of a function f(r) is given by
where is the Bessel function of the first kind of order with . The inverse Hankel transform of is defined as
which can be readily verified using the orthogonality relationship described below.
Domain of definition
Inverting a Hankel transform of a function f(r) is valid at every point at which f(r) is continuous, provided that the function is defined in (0, ∞), is piecewise continuous and of bounded variation in every finite subinterval in (0, ∞), and
However, like the Fourier transform, the domain can be extended by a density argument to include some functions whose above integral is not finite, for example .
Alt
|
https://en.wikipedia.org/wiki/James%20Hadley%20%28scholar%29
|
James Hadley (March 30, 1821 – November 14, 1872) was an American philologist who taught Greek and Hebrew languages at Yale College.
Biography
Hadley was born in Fairfield, New York, where his father was professor of chemistry at Fairfield Medical College. At the age of nine, a knee injury left him lame for life. Hadley received his early instruction at the Fairfield Academy, and also acquired some scientific knowledge from his father. He became assistant at the Academy, and later graduated from Yale College in 1842, having entered the junior class in 1840. Hadley was then a resident graduate at Yale for a year, after which he entered Yale's theological seminary, where he spent two years.
From April to September 1845, Hadley was a tutor at Middlebury College. He was a tutor at Yale in 1845–1848, an assistant professor of Greek in 1848–1851, and a professor of Greek, succeeding President Woolsey, from 1851 until his death in New Haven, Connecticut.
As an undergraduate, Hadley had proven an able mathematician, but the influence of Edward Elbridge Salisbury, under whom Hadley and William Dwight Whitney studied Sanskrit together, turned his attention toward the study of language. He knew Greek, Latin, Sanskrit, Hebrew, Arabic, Armenian, several Celtic languages, and the languages of modern Europe; but he published little, and his scholarship found scant outlet in the college classroom.
Hadley was well versed in civil law. His course of lectures on civil law was included in th
|
https://en.wikipedia.org/wiki/Physics%20engine
|
A physics engine is computer software that provides an approximate simulation of certain physical systems, such as rigid body dynamics (including collision detection), soft body dynamics, and fluid dynamics, of use in the domains of computer graphics, video games and film (CGI). Their main uses are in video games (typically as middleware), in which case the simulations are in real-time. The term is sometimes used more generally to describe any software system for simulating physical phenomena, such as high-performance scientific simulation.
Description
There are generally two classes of physics engines: real-time and high-precision. High-precision physics engines require more processing power to calculate very precise physics and are usually used by scientists and computer-animated movies. Real-time physics engines—as used in video games and other forms of interactive computing—use simplified calculations and decreased accuracy to compute in time for the game to respond at an appropriate rate for game play. A physics engine is essentially a big calculator that does mathematics needed to simulate physics.
Scientific engines
One of the first general purpose computers, ENIAC, was used as a very simple type of physics engine. It was used to design ballistics tables to help the United States military estimate where artillery shells of various mass would land when fired at varying angles and gunpowder charges, also accounting for drift caused by wind. The results were calculat
|
https://en.wikipedia.org/wiki/Free%20field
|
In physics a free field is a field without interactions, which is described by the terms of motion and mass.
Description
In classical physics, a free field is a field whose equations of motion are given by linear partial differential equations. Such linear PDE's have a unique solution for a given initial condition.
In quantum field theory, an operator valued distribution is a free field if it satisfies some linear partial differential equations such that the corresponding case of the same linear PDEs for a classical field (i.e. not an operator) would be the Euler–Lagrange equation for some quadratic Lagrangian. We can differentiate distributions by defining their derivatives via differentiated test functions. See Schwartz distribution for more details. Since we are dealing not with ordinary distributions but operator valued distributions, it is understood these PDEs aren't constraints on states but instead a description of the relations among the smeared fields. Beside the PDEs, the operators also satisfy another relation, the commutation/anticommutation relations.
Canonical Commutation Relation
Basically, commutator (for bosons)/anticommutator (for fermions) of two smeared fields is i times the Peierls bracket of the field with itself (which is really a distribution, not a function) for the PDEs smeared over both test functions. This has the form of a CCR/CAR algebra.
CCR/CAR algebras with infinitely many degrees of freedom have many inequivalent irreducible unitary r
|
https://en.wikipedia.org/wiki/Null%20vector
|
In mathematics, given a vector space X with an associated quadratic form q, written , a null vector or isotropic vector is a non-zero element x of X for which .
In the theory of real bilinear forms, definite quadratic forms and isotropic quadratic forms are distinct. They are distinguished in that only for the latter does there exist a nonzero null vector.
A quadratic space which has a null vector is called a pseudo-Euclidean space.
A pseudo-Euclidean vector space may be decomposed (non-uniquely) into orthogonal subspaces A and B, , where q is positive-definite on A and negative-definite on B. The null cone, or isotropic cone, of X consists of the union of balanced spheres:
The null cone is also the union of the isotropic lines through the origin.
Split algebras
A composition algebra with a null vector is a split algebra.
In a composition algebra (A, +, ×, *), the quadratic form is q(x) = x x*. When x is a null vector then there is no multiplicative inverse for x, and since x ≠ 0, A is not a division algebra.
In the Cayley–Dickson construction, the split algebras arise in the series bicomplex numbers, biquaternions, and bioctonions, which uses the complex number field as the foundation of this doubling construction due to L. E. Dickson (1919). In particular, these algebras have two imaginary units, which commute so their product, when squared, yields +1:
Then
so 1 + hi is a null vector.
The real subalgebras, split complex numbers, split quaternions, and split-octon
|
https://en.wikipedia.org/wiki/Seamus%20Blackley
|
Jonathan "Seamus" Blackley (born 1968) is an American video game designer and former agent with Creative Artists Agency representing video game creators. He is best known for creating and designing the original Xbox in 2001.
Career
After entering Tufts University to study electrical engineering, Blackley switched to study physics and graduated in 1990, . As an undergraduate, he published his first paper in the Journal of Magnetic Resonance. After college, he studied high energy physics at the Fermi National Accelerator Laboratory, until the Superconducting Supercollider project was cancelled in 1993.
Blackley then went to work at Blue Sky Productions, later called Looking Glass Studios. In addition to his work on Ultima Underworld and System Shock, Blackley helped to create the sophisticated physics system in Flight Unlimited. He is mentioned in the Flight Unlimited manual as follows:
Following the completion of Flight Unlimited in 1995, Blackley planned to use that game's computational fluid dynamics (CFDs) code to create a combat flight simulator called Flight Combat. However, a new manager at Looking Glass Studios demanded that Blackley instead design a direct sequel to Flight Unlimited as to directly compete with Microsoft Flight Simulator. Blackley refused and was fired, leaving the company in late 1995.
After Looking Glass, Blackley worked at DreamWorks Interactive as executive producer of Jurassic Park: Trespasser, a video game sequel to the film The Lost World:
|
https://en.wikipedia.org/wiki/Boxcar%20function
|
In mathematics, a boxcar function is any function which is zero over the entire real line except for a single interval where it is equal to a constant, A. The function is named after its graph's resemblance to a boxcar, a type of railroad car. The boxcar function can be expressed in terms of the uniform distribution as
where is the uniform distribution of x for the interval and is the Heaviside step function. As with most such discontinuous functions, there is a question of the value at the transition points. These values are probably best chosen for each individual application.
When a boxcar function is selected as the impulse response of a filter, the result is a simple moving average filter, whose frequency response is a sinc-in-frequency, a type of low-pass filter.
See also
Boxcar averager
Rectangular function
Step function
Top-hat filter
References
Special functions
|
https://en.wikipedia.org/wiki/Carlo%20Beenakker
|
Carlo Willem Joannes Beenakker (born 9 June 1960) is a professor at Leiden University and leader of the university's mesoscopic physics group, established in 1992.
Early life and education
Born in Leiden as the son of physicists Jan Beenakker and Elena Manaresi, Beenakker graduated from Leiden University in 1982 and obtained his doctorate two years later.
Career
After the awarding of his doctorate, he then spent one year working in the United States of America as a fellow of the Niels Stensen Foundation before returning to the Netherlands as a member of the scientific staff of the Philips Research Laboratories in Eindhoven. He was made External Professor of Theoretical Physics at Leiden in 1991.
His work in mesoscopic physics addresses fundamental physical problems that occur when a macroscopic object is miniaturized.
In 1993, he shared the Royal/Shell prize for "the discovery and explanation of quantum effects in the electrical conduction in mesoscopic systems". He was elected a member of the Royal Holland Society of Sciences and Humanities in 2001, and the Royal Netherlands Academy of Arts and Sciences in 2002. He was awarded one of the Netherlands' most prestigious science awards, the Spinozapremie, in 1999. In 2006 he was honored with the AkzoNobel Science Award "for his pioneering work in the field of nanoscience".
In a 1997 study by the Institute for Scientific Information, Beenakker rated in the top 300 most cited physicists of the previous 16 years.
In 2008, Bee
|
https://en.wikipedia.org/wiki/Sigma%20approximation
|
In mathematics, σ-approximation adjusts a Fourier summation to greatly reduce the Gibbs phenomenon, which would otherwise occur at discontinuities.
A σ-approximated summation for a series of period T can be written as follows:
in terms of the normalized sinc function
The term
is the Lanczos σ factor, which is responsible for eliminating most of the Gibbs phenomenon. It does not do so entirely, however, but one can square or even cube the expression to serially attenuate Gibbs phenomenon in the most extreme cases.
See also
Lanczos resampling
References
Fourier series
Numerical analysis
|
https://en.wikipedia.org/wiki/Pseudotensor
|
In physics and mathematics, a pseudotensor is usually a quantity that transforms like a tensor under an orientation-preserving coordinate transformation (e.g. a proper rotation) but additionally changes sign under an orientation-reversing coordinate transformation (e.g., an improper rotation), which is a transformation that can be expressed as a proper rotation followed by reflection. This is a generalization of a pseudovector. To evaluate a tensor or pseudotensor sign, it has to be contracted with some vectors, as many as its rank is, belonging to the space where the rotation is made while keeping the tensor coordinates unaffected (differently from what one does in the case of a base change). Under improper rotation a pseudotensor and a proper tensor of the same rank will have different sign which depends on the rank being even or odd. Sometimes inversion of the axes is used as an example of an improper rotation to see the behaviour of a pseudotensor, but it works only if vector space dimensions is odd otherwise inversion is a proper rotation without an additional reflection.
There is a second meaning for pseudotensor (and likewise for pseudovector), restricted to general relativity. Tensors obey strict transformation laws, but pseudotensors in this sense are not so constrained. Consequently, the form of a pseudotensor will, in general, change as the frame of reference is altered. An equation containing pseudotensors which holds in one frame will not necessarily hold in a d
|
https://en.wikipedia.org/wiki/Joseph%20Gaertner
|
Joseph Gaertner (12 March 1732 – 14 July 1791) was a German botanist, best known for his work on seeds, De Fructibus et Seminibus Plantarum (1788-1792).
Biography
He was born in Calw, and studied in Göttingen under Albrecht von Haller. He was primarily a naturalist, but also worked at physics and zoology. He travelled extensively to visit other naturalists. He was professor of anatomy in Tübingen in 1760, and was appointed professor of botany at St Petersburg in 1768, but returned to Calw in 1770.
Gaertner made back cross to convert one species into another. Back cross increases nuclear gene frequency
His observations were:
1. Dominance of traits
2. Equal contribution of male and female to the progeny
3. No variation in F1 (first generation of descendants)
4. Large variation in F2 (second generation of descendants) including parental and intermediate types
5. Some of F2 plants had entirely new traits
but he was unable to give possible explanation for observed data but which was brilliantly done by Mendel
Julius Sachs writes
De Fructibus
By 1770 he had already begun work on his De Fructibus et Seminibus Plantarum, but thereafter he gave himself up almost entirely to it, becoming nearly blind through his persistent studies, partly with the microscope. The work's minutely accurate descriptions, comprising a thousand and more species, introduced a new era in plant morphology. The scientific value of the book was much increased by the addition of 180 copper-plate e
|
https://en.wikipedia.org/wiki/Maceration
|
Maceration may refer to:
Maceration (food), in food preparation
Maceration (wine), a step in wine-making
Carbonic maceration, a wine-making technique
Maceration (sewage), in sewage treatment
Maceration (bone), a method of preparing bones
Acid maceration, the use of an acid to extract micro-fossils from rock
Maceration, in chemistry, the preparation of an extract by solvent extraction
Maceration, in biology, the mechanical breakdown of ingested food into chyme
Skin maceration, in dermatology, the softening and whitening of skin that is kept constantly wet
Maceration, in poultry farming, a method of chick culling
|
https://en.wikipedia.org/wiki/BEST%20theorem
|
In graph theory, a part of discrete mathematics, the BEST theorem gives a product formula for the number of Eulerian circuits in directed (oriented) graphs. The name is an acronym of the names of people who discovered it: de Bruijn, van Aardenne-Ehrenfest, Smith and Tutte.
Precise statement
Let G = (V, E) be a directed graph. An Eulerian circuit is a directed closed path which visits each edge exactly once. In 1736, Euler showed that G has an Eulerian circuit if and only if G is connected and the indegree is equal to outdegree at every vertex. In this case G is called Eulerian. We denote the indegree of a vertex v by deg(v).
The BEST theorem states that the number ec(G) of Eulerian circuits in a connected Eulerian graph G is given by the formula
Here tw(G) is the number of arborescences, which are trees directed towards the root at a fixed vertex w in G. The number tw(G) can be computed as a determinant, by the version of the matrix tree theorem for directed graphs. It is a property of Eulerian graphs that tv(G) = tw(G) for every two vertices v and w in a connected Eulerian graph G.
Applications
The BEST theorem shows that the number of Eulerian circuits in directed graphs can be computed in polynomial time, a problem which is #P-complete for undirected graphs. It is also used in the asymptotic enumeration of Eulerian circuits of complete and complete bipartite graphs.
History
The BEST theorem is due to van Aardenne-Ehrenfest and de Bruijn
(1951), §6, Theorem
|
https://en.wikipedia.org/wiki/Instituto%20de%20Biolog%C3%ADa%20y%20Medicina%20Experimental
|
The Experimental Medicine and Biology Institute (, IByME) is a research and development centre affiliated to the University of Buenos Aires, in Buenos Aires, Argentina.
History
The institute was privately founded on March 14, 1944, by Dr. Bernardo A. Houssay, Nobel Prize in Physiology and Medicine (1947) for his work in diabetes and the control of the carbohydrate metabolism. Drs. Eduardo Braun-Menéndez, Oscar Orías, Juan T. Lewis and Virgilio G. Foglia were co-founders. The founding of the institute was motivated by the dismissal of Dr. Houssay, together with 150 other professors from the University of Buenos Aires, by the military government. Dr. Houssay became its director and brought to work with him several colleagues and students. The initiative was made possible by the support of Dr. Miguel F. Laphitzondo and others who granted financial contributions in memory of Juan B. Sauberán.
The institute was the first organization devoted to scientific research in Argentina. Its initial structure resembled that of the Rockefeller Institute for Medical Research (now Rockefeller University, New York, United States) and of the Pasteur Institute, Paris, France. In 1949, the institute was established as a chartered foundation recognized by the National Bureau of Non-Profit Entitites (Registro Nacional de Entidades de Bien Público).
Later on, several Houssay's disciples left the institute to settle research groups in many Argentine and other Latin American universities. Many rese
|
https://en.wikipedia.org/wiki/Dynamic%20array
|
In computer science, a dynamic array, growable array, resizable array, dynamic table, mutable array, or array list is a random access, variable-size list data structure that allows elements to be added or removed. It is supplied with standard libraries in many modern mainstream programming languages. Dynamic arrays overcome a limit of static arrays, which have a fixed capacity that needs to be specified at allocation.
A dynamic array is not the same thing as a dynamically allocated array or variable-length array, either of which is an array whose size is fixed when the array is allocated, although a dynamic array may use such a fixed-size array as a back end.
Bounded-size dynamic arrays and capacity
A simple dynamic array can be constructed by allocating an array of fixed-size, typically larger than the number of elements immediately required. The elements of the dynamic array are stored contiguously at the start of the underlying array, and the remaining positions towards the end of the underlying array are reserved, or unused. Elements can be added at the end of a dynamic array in constant time by using the reserved space, until this space is completely consumed. When all space is consumed, and an additional element is to be added, then the underlying fixed-size array needs to be increased in size. Typically resizing is expensive because it involves allocating a new underlying array and copying each element from the original array. Elements can be removed from the end o
|
Subsets and Splits
No community queries yet
The top public SQL queries from the community will appear here once available.