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https://en.wikipedia.org/wiki/Organizational%20ecology
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Organizational ecology (also organizational demography and the population ecology of organizations) is a theoretical and empirical approach in the social sciences that is considered a sub-field of organizational studies. Organizational ecology utilizes insights from biology, economics, and sociology, and employs statistical analysis to try to understand the conditions under which organizations emerge, grow, and die.
The ecology of organizations is divided into three levels, the community, the population, and the organization. The community level is the functionally integrated system of interacting populations. The population level is the set of organizations engaged in similar activities. The organization level focuses on the individual organizations (some research further divides organizations into individual member and sub-unit levels).
What is generally referred to as organizational ecology in research is more accurately population ecology, focusing on the second level.
Development
Wharton School researcher William Evan called the population level the organization-set, and focused on the interrelations of individual organizations within the population as early as 1966. However, prior to the mid-1970s, the majority of organizational studies research focused on adaptive change in organizations (See also adaptive management and adaptive performance). The ecological approach moved focus to the environmental selection processes that affect organizations.
In 1976, Eric T
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https://en.wikipedia.org/wiki/Population%20ecology
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Population ecology is a sub-field of ecology that deals with the dynamics of species populations and how these populations interact with the environment, such as birth and death rates, and by immigration and emigration.
The discipline is important in conservation biology, especially in the development of population viability analysis which makes it possible to predict the long-term probability of a species persisting in a given patch of habitat. Although population ecology is a subfield of biology, it provides interesting problems for mathematicians and statisticians who work in population dynamics.
History
In the 1940s ecology was divided into autecology—the study of individual species in relation to the environment—and synecology—the study of groups of species in relation to the environment. The term autecology (from Ancient Greek: αὐτο, aúto, "self"; οίκος, oíkos, "household"; and λόγος, lógos, "knowledge"), refers to roughly the same field of study as concepts such as life cycles and behaviour as adaptations to the environment by individual organisms. Eugene Odum, writing in 1953, considered that synecology should be divided into population ecology, community ecology and ecosystem ecology, renaming autecology as 'species ecology' (Odum regarded "autecology" as an archaic term), thus that there were four subdivisions of ecology.
Terminology
A population is defined as a group of interacting organisms of the same species. A demographic structure of a population is how pop
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https://en.wikipedia.org/wiki/Henry%20Stapp
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Henry Pierce Stapp (born March 23, 1928 in Cleveland, Ohio) is an American mathematical physicist, known for his work in quantum mechanics, particularly the development of axiomatic S-matrix theory, the proofs of strong nonlocality properties, and the place of free will in the "orthodox" quantum mechanics of John von Neumann.
Biography
Stapp received his PhD in particle physics at the University of California, Berkeley, under the supervision of Nobel Laureates Emilio Segrè and Owen Chamberlain.
In 1958, Stapp was invited by Wolfgang Pauli to ETH Zurich to work with him personally on basic problems in quantum mechanics. When Pauli died in December 1958, Stapp studied von Neumann's book, and on the basis of that work composed an article entitled "Mind, Matter and Quantum Mechanics", which was not submitted for publication; but the title became the title of his 1993 book.
In 1969 Stapp was invited by Werner Heisenberg to work with him at the Max Planck Institute in Munich.
In 1976 Stapp was invited by J.A. Wheeler to work with him on problems in the foundations of Quantum Mechanics. Dr. Stapp has published many papers pertaining to the non-local aspects of quantum mechanics and Bell's theorem, including
three books published by Springer-Verlag.
Stapp has worked also in a number of conventional areas of high energy physics, including analysis of the scattering of polarized protons, parity violation, and S-matrix theory.
Research
Some of Stapp's work concerns the implica
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https://en.wikipedia.org/wiki/Hasse%E2%80%93Weil%20zeta%20function
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In mathematics, the Hasse–Weil zeta function attached to an algebraic variety V defined over an algebraic number field K is a meromorphic function on the complex plane defined in terms of the number of points on the variety after reducing modulo each prime number p. It is a global L-function defined as an Euler product of local zeta functions.
Hasse–Weil L-functions form one of the two major classes of global L-functions, alongside the L-functions associated to automorphic representations. Conjecturally, these two types of global L-functions are actually two descriptions of the same type of global L-function; this would be a vast generalisation of the Taniyama-Weil conjecture, itself an important result in number theory.
For an elliptic curve over a number field K, the Hasse–Weil zeta function is conjecturally related to the group of rational points of the elliptic curve over K by the Birch and Swinnerton-Dyer conjecture.
Definition
The description of the Hasse–Weil zeta function up to finitely many factors of its Euler product is relatively simple. This follows the initial suggestions of Helmut Hasse and André Weil, motivated by the case in which V is a single point, and the Riemann zeta function results.
Taking the case of K the rational number field Q, and V a non-singular projective variety, we can for almost all prime numbers p consider the reduction of V modulo p, an algebraic variety Vp over the finite field Fp with p elements, just by reducing equations for V. Sc
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https://en.wikipedia.org/wiki/Photoisomerization
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In chemistry, photoisomerization is a form of isomerization induced by photoexcitation. Both reversible and irreversible photoisomerizations are known for photoswitchable compounds. The term "photoisomerization" usually, however, refers to a reversible process.
Applications
Photoisomerization of the compound retinal in the eye allows for vision.
Photoisomerizable substrates have been put to practical use, for instance, in pigments for rewritable CDs, DVDs, and 3D optical data storage solutions. In addition, interest in photoisomerizable molecules has been aimed at molecular devices, such as molecular switches, molecular motors, and molecular electronics.
Another class of device that uses the photoisomerization process is as an additive in liquid crystals to change their linear and nonlinear properties. Due to the photoisomerization is possible to induce a molecular reorientation in the liquid crystal bulk, which is used in holography, as spatial filter or optical switching.
Examples
Azobenzenes, stilbenes, spiropyrans, are prominent classes of compounds subject to photoisomerism.
In the presence of a catalyst, norbornadiene converts to quadricyclane via ~300nm UV radiation . When converted back to norbornadiene, quadryicyclane’s ring strain energy is liberated in the form of heat (ΔH = −89 kJ/mol). This reaction has been proposed to store solar energy (photoswitchs).
Photoisomerization behavior can be roughly categorized into several classes. Two major classes are trans
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https://en.wikipedia.org/wiki/Supersymmetric%20quantum%20mechanics
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In theoretical physics, supersymmetric quantum mechanics is an area of research where supersymmetry are applied to the simpler setting of plain quantum mechanics, rather than quantum field theory. Supersymmetric quantum mechanics has found applications outside of high-energy physics, such as providing new methods to solve quantum mechanical problems, providing useful extensions to the WKB approximation, and statistical mechanics.
Introduction
Understanding the consequences of supersymmetry (SUSY) has proven mathematically daunting, and it has likewise been difficult to develop theories that could account for symmetry breaking, i.e., the lack of observed partner particles of equal mass. To make progress on these problems, physicists developed supersymmetric quantum mechanics, an application of the supersymmetry superalgebra to quantum mechanics as opposed to quantum field theory. It was hoped that studying SUSY's consequences in this simpler setting would lead to new understanding; remarkably, the effort created new areas of research in quantum mechanics itself.
For example, students are typically taught to "solve" the hydrogen atom by a laborious process which begins by inserting the Coulomb potential into the Schrödinger equation. After a considerable amount of work using many differential equations, the analysis produces a recursion relation for the Laguerre polynomials. The final outcome is the spectrum of hydrogen-atom energy states (labeled by quantum numbers n and
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https://en.wikipedia.org/wiki/List%20of%20Indian%20mathematicians
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The chronology of Indian mathematicians spans from the Indus Valley civilisation and the Vedas to Modern India.
Indian mathematicians have made a number of contributions to mathematics that have significantly influenced scientists and mathematicians in the modern era. Hindu-Arabic numerals predominantly used today and likely into the future.
Ancient (Before 320 CE)
Baudhayana sutras (fl. c. 900 BCE)
Yajnavalkya (700 BCE)
Manava (fl. 750–650 BCE)
Apastamba Dharmasutra (c. 600 BCE)
Pāṇini (c. 520–460 BCE)
Kātyāyana (fl. c. 300 BCE)
Akṣapada Gautama(c. 600 BCE–200 CE)
Bharata Muni (200 BCE-200 CE)
Pingala (c. 3rd/2nd century BCE)
Bhadrabahu (367 – 298 BCE)
Umasvati (c. 200 CE)
Yavaneśvara (2nd century)
Vasishtha Siddhanta, 4th century CE
Classical (320 CE–520 CE)
Vasishtha Siddhanta, 4th century CE
Aryabhata (476–550 CE)
Yativrsabha (500–570)
Varahamihira (505–587 CE)
Yativṛṣabha, (6th-century CE)
Virahanka (6th century CE)
Early Medieval Period (521 CE–1206 CE)
Brahmagupta (598–670 CE)
Bhaskara I (600–680 CE)
Shridhara (between 650–850 CE)
Lalla (c. 720–790 CE)
Virasena (792–853 CE)
Govindasvāmi (c. 800 – c. 860 CE)
Prithudaka (c. 830 – c. 900CE)
Śaṅkaranārāyaṇa, (c. 840 – c. 900 CE)
Vaṭeśvara (born 880 CE)
Mahavira (9th century CE)
Jayadeva 9th century CE
Aryabhata II (920 – c. 1000)
Vijayanandi (c. 940–1010)
Halayudha 10th Century
Śrīpati (1019–1066)
Abhayadeva Suri (1050 CE)
Brahmadeva (1060–1130)
Pavuluri Mallana (11th century CE)
Hema
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https://en.wikipedia.org/wiki/Mike%20Lewis%20%28musician%29
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Michael Richard Lewis (born 17 August 1977) is a Welsh musician. He is best known as the former rhythm guitarist for the Welsh alternative rock band Lostprophets, Welsh/American alternative rock band No Devotion and hardcore punk band Public Disturbance.
Early life
Lewis studied civil engineering for a year before turning to music. His mother was a shop assistant, and his father worked in management for a chemical company. Lewis attended Hawthorn High School in Pontypridd. His favourite subjects were Science and History. His first concert, as a concertgoer, came when he saw Tesla at St David's Hall.
Career
Before Lostprophets formed, Lewis was in a band called Public Disturbance. He was initially the original bassist for Lostprophets, but soon became the rhythm guitarist, with Stuart Richardson replacing him on the bass guitar. After the split of Lostprophets in 2013, Lewis became the manager to a few smaller bands.
On 1 May 2014 it was announced that the former members of Lostprophets (including Lewis) have formed a new band and are writing new music. On 1 July 2014, the new band No Devotion released their first single, "Stay" and have since released their debut album, Permanence.
Lee Gaze confirmed that keyboardist Jamie Oliver had departed from the band while also stating that Lewis had not left the band, but he hadn't worked with the other band members on the following album No Oblivion.
Personal life
In September 2006, Lewis married his girlfriend, Amber (née Payne)
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https://en.wikipedia.org/wiki/Virahanka
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Virahanka (Devanagari: विरहाङ्क) was an Indian prosodist who is also known for his work on mathematics. He may have lived in the 6th century, but it is also possible that he worked as late as the 8th century.
His work on prosody builds on the Chhanda-sutras of Pingala (4th century BCE), and was the basis for a 12th-century commentary by Gopala.
He was the first to propose the so-called Fibonacci Sequence.
See also
Indian mathematicians
References
External links
The So-called Fibonacci Numbers in Ancient and Medieval India by Parmanand Singh
8th-century Indian mathematicians
Fibonacci numbers
Medieval Sanskrit grammarians
Ancient Indian mathematical works
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https://en.wikipedia.org/wiki/Mah%C4%81v%C4%ABra%20%28mathematician%29
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Mahāvīra (or Mahaviracharya, "Mahavira the Teacher") was a 9th-century Jain mathematician possibly born in Mysore, in India. He authored Gaṇita-sāra-saṅgraha (Ganita Sara Sangraha) or the Compendium on the gist of Mathematics in 850 AD. He was patronised by the Rashtrakuta king Amoghavarsha. He separated astrology from mathematics. It is the earliest Indian text entirely devoted to mathematics. He expounded on the same subjects on which Aryabhata and Brahmagupta contended, but he expressed them more clearly. His work is a highly syncopated approach to algebra and the emphasis in much of his text is on developing the techniques necessary to solve algebraic problems. He is highly respected among Indian mathematicians, because of his establishment of terminology for concepts such as equilateral, and isosceles triangle; rhombus; circle and semicircle. Mahāvīra's eminence spread throughout South India and his books proved inspirational to other mathematicians in Southern India. It was translated into the Telugu language by Pavuluri Mallana as Saara Sangraha Ganitamu.
He discovered algebraic identities like a3 = a (a + b) (a − b) + b2 (a − b) + b3. He also found out the formula for nCr as [n (n − 1) (n − 2) ... (n − r + 1)] / [r (r − 1) (r − 2) ... 2 * 1]. He devised a formula which approximated the area and perimeters of ellipses and found methods to calculate the square of a number and cube roots of a number. He asserted that the square root of a negative number does not exist.
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https://en.wikipedia.org/wiki/Isotype
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Isotype can refer to:
Isotype (biology), a duplicate of the holotype of a species
Isotype (crystallography), a synonym for isomorph
Isotype (immunology), an antibody class according to its Fc region
Isotype (picture language), a method of showing social, technological, biological and historical connections in pictorial form
Isotype (song), 2017 song by Orchestral Manoeuvres in the Dark
See also
Isotope (disambiguation)
Isoform
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https://en.wikipedia.org/wiki/Va%E1%B9%ADe%C5%9Bvara
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Vaṭeśvara ( ) (born 880), was a tenth-century Indian mathematician from Kashmir who presented several trigonometric identities. He was the author (at the age of 24) of Vaṭeśvara-siddhānta written in 904 AD, a treatise focusing on astronomy and applied mathematics.The work criticized Brahmagupta and defended Aryabhatta I. An edition of the first three chapters was published in 1962 by R. S. Sharma and Mukund Mishra. Al Biruni referred to the works by Vateswara, particularly the Karaṇasāra, noting that the author was the son of Mihdatta who belonged to Nagarapura (also given as Anandapura which is now Vadnagar). The Karaṇasāra uses 821 Saka era (899 AD) as a reference year.
References
Other sources
K. V. Sarma (1997), "Vatesvara", Encyclopaedia of the History of Science, Technology, and Medicine in Non-Western Cultures edited by Helaine Selin, Springer,
Kashmiri people
880 births
10th-century Indian mathematicians
Year of death unknown
9th-century Indian mathematicians
Scholars from Jammu and Kashmir
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https://en.wikipedia.org/wiki/Parameshvara%20Nambudiri
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Vatasseri Parameshvara Nambudiri ( 1380–1460) was a major Indian mathematician and astronomer of the Kerala school of astronomy and mathematics founded by Madhava of Sangamagrama. He was also an astrologer. Parameshvara was a proponent of observational astronomy in medieval India and he himself had made a series of eclipse observations to verify the accuracy of the computational methods then in use. Based on his eclipse observations, Parameshvara proposed several corrections to the astronomical parameters which had been in use since the times of Aryabhata. The computational scheme based on the revised set of parameters has come to be known as the Drgganita or Drig system. Parameshvara was also a prolific writer on matters relating to astronomy. At least 25 manuscripts have been identified as being authored by Parameshvara.
Biographical details
Parameshvara was a Hindu of Bhrgugotra following the Ashvalayanasutra of the Rigveda. Parameshvara's family name (Illam) was Vatasseri and his family resided in the village of Alathiyur (Sanskritised as Asvatthagrama) in Tirur, Kerala. Alathiyur is situated on the northern bank of the river Nila (river Bharathappuzha) at its mouth in Kerala. He was a grandson of a disciple of Govinda Bhattathiri (1237–1295 CE), a legendary figure in the astrological traditions of Kerala.
Parameshvara studied under teachers Rudra and Narayana, and also under Madhava of Sangamagrama (c. 1350 – c. 1425) the founder of the Kerala school of astronomy and
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https://en.wikipedia.org/wiki/Mahendra%20S%C5%ABri
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Mahendra Sūri (c. 1340 – 1400) is the 14th century Jain astronomer who wrote the Yantraraja, the first Indian treatise on the astrolabe. He was trained by Madana Sūri, and was teacher to Malayendu Sūri. Jainism had a strong influence on mathematics particularly in the last couple of centuries BC. By the time of Mahendra Suri, however, Jainism had lost support as a national religion and was much less vigorous.
Works
Mahendra Suri's fame rests on the work Yantrarāja, which introduced the astrolabe to the Indian astronomer. Mahendra Sūri was patronized by the Tughluq ruler of Delhi, Firūz Shāh (r. 1351–1388), who evinced keen interest in astronomy. Firūz Shāh had earlier caused the Bṛhatsaṃhitā of Varāhamihira to be translated into Persian. At the sultan's instance, Mahendra Sūri studied the astrolabe and introduced it to the Sanskrit audience in 1370 in his Yantrarāja. Its circulation was largely, if not wholly, confined to astronomers who worked within the Islamic and Ptolemaic traditions.
The Yantrarāja is best described as an astrolabe user's manual. It explains how this king (rāja) of instruments (yantra) is to be constructed and commissioned for purposes of observation. The saumya yantra (northern instrument) projected from the South Pole and the yāmya yantra (southern instrument) projected from the North Pole are discussed separately, followed by a description of the phaṇīndra yantra (the serpentine instrument), which combines both.
A detailed discussion on the applica
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https://en.wikipedia.org/wiki/Baudhayana%20sutras
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The (Sanskrit: बौधायन) are a group of Vedic Sanskrit texts which cover dharma, daily ritual, mathematics and is one of the oldest Dharma-related texts of Hinduism that have survived into the modern age from the 1st-millennium BCE. They belong to the Taittiriya branch of the Krishna Yajurveda school and are among the earliest texts of the genre.
The Baudhayana sūtras consist of six texts:
the , probably in 19 (questions),
the in 20 (chapters),
the in 4 ,
the Grihyasutra in 4 ,
the in 4 and
the in 3 .
The is noted for containing several early mathematical results, including an approximation of the square root of 2 and the statement of the Pythagorean theorem.
Baudhāyana Shrautasūtra
His Śrauta sūtras related to performing Vedic sacrifices have followers in some Smārta brāhmaṇas (Iyers) and some Iyengars of Tamil Nadu, Yajurvedis or Namboothiris of Kerala, Gurukkal Brahmins (Aadi Saivas) and Kongu Vellalars. The followers of this sūtra follow a different method and do 24 Tila-tarpaṇa, as Lord Krishna had done tarpaṇa on the day before amāvāsyā; they call themselves Baudhāyana Amavasya.
Baudhāyana Dharmasūtra
The Dharmasūtra of Baudhāyana like that of Apastamba also forms a part of the larger Kalpasutra. Likewise, it is composed of praśnas which literally means 'questions' or books. The structure of this Dharmasūtra is not very clear because it came down in an incomplete manner. Moreover, the text has undergone alterations in the form of additions and
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https://en.wikipedia.org/wiki/Reef%20aquarium
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A reef aquarium or reef tank is a marine aquarium that prominently displays live corals and other marine invertebrates as well as fish that play a role in maintaining the tropical coral reef environment. A reef aquarium requires appropriately intense lighting, turbulent water movement, and more stable water chemistry than fish-only marine aquaria, and careful consideration is given to which reef animals are appropriate and compatible with each other.
Components
Reef aquariums consist of a number of components, in addition to the livestock, including:
Display tank: The primary tank in which the livestock are kept and shown.
Stand: A stand allows for placement of the display tank at eye level and provides space for storage of the accessory components.
Sump: An accessory tank in which mechanical equipment is kept. A remote sump allows for a clutter-free display tank.
Refugium: An accessory tank dedicated to the cultivation of beneficial macroalgae and microflora/fauna. The refugium and sump are often housed in a single tank with a system of dividers to separate the compartments.
Lighting: Several lighting options are available for the reef-keeper and are tailored to the types of coral kept.
Canopy: The canopy houses the light fixtures and provides access to the tank for feeding and maintenance.
Filtration and water movement: A variety of filtration and water movement strategies are employed in reef aquaria. Bulky equipment is often relegated to the sump.
Display tank
A "ree
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https://en.wikipedia.org/wiki/Neil%20Gershenfeld
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Neil Adam Gershenfeld (born December 1, 1959) is an American professor at MIT and the director of MIT's Center for Bits and Atoms, a sister lab to the MIT Media Lab. His research studies are predominantly focused in interdisciplinary studies involving physics and computer science, in such fields as quantum computing, nanotechnology, and personal fabrication. Gershenfeld attended Swarthmore College, where he graduated in 1981 with a B.A. degree in physics with high honors, and Cornell University, where he earned his Ph.D.in physics in 1990. He is a Fellow of the American Physical Society. Scientific American has named Gershenfeld one of their "Scientific American 50" for 2004 and has also named him Communications Research Leader of the Year. Gershenfeld is also known for releasing the Great Invention Kit in 2008, a construction set that users can manipulate to create various objects.
Gershenfeld has been featured in a variety of newspapers and magazines such as The New York Times and The Economist, and on NPR.
He was named as one of the 40 modern-day Leonardos by the Museum of Science and Industry Chicago. Prospect named him as one of the top 100 public intellectuals.
Teaching career
In 1998, Gershenfeld started a class at MIT called "How to make (almost) anything". Gershenfeld wanted to introduce expensive, industrial-size machines to the technical students. However, this class attracted a lot of students from various backgrounds: artists, architects, designers, students w
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https://en.wikipedia.org/wiki/Chartered%20Mathematician
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Chartered Mathematician (CMath) is a professional qualification in Mathematics awarded to professional practising mathematicians by the Institute of Mathematics and its Applications (IMA) in the United Kingdom.
Chartered Mathematician is the IMA's highest professional qualification; achieving it is done through a rigorous peer-reviewed process. It provides formal recognition of a member’s qualifications in Mathematics, professional practise of Mathematics at an advanced level, technical standing, and commitment to remain at the forefront of Mathematics theory and practise throughout one's professional career.
The required standard for Chartered Mathematician registration is typically an accredited UK MMath degree, at least five years of peer-reviewed professional practise of advanced Mathematics, attainment of a senior-level of technical standing, and an ongoing commitment to Continuing Professional Development.
A Chartered Mathematician is entitled to use the post-nominal letters CMath, in accordance with the Royal Charter granted to the IMA by the Privy Council. The profession of Chartered Mathematician is a 'regulated profession' under the European professional qualification directives.
See also
Institute of Mathematics and its Applications
References
External links
Institute of Mathematics and its Applications website
Mathematics education in the United Kingdom
Mathematician
Mathematics
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https://en.wikipedia.org/wiki/Homeosis
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In evolutionary developmental biology, homeosis is the transformation of one organ into another, arising from mutation in or misexpression of certain developmentally critical genes, specifically homeotic genes. In animals, these developmental genes specifically control the development of organs on their anteroposterior axis. In plants, however, the developmental genes affected by homeosis may control anything from the development of a stamen or petals to the development of chlorophyll. Homeosis may be caused by mutations in Hox genes, found in animals, or others such as the MADS-box family in plants. Homeosis is a characteristic that has helped insects become as successful and diverse as they are.
Homeotic mutations work by changing segment identity during development. For example, the Ultrabithorax genotype gives a phenotype wherein metathoracic and first abdominal segments become mesothoracic segments. Another well-known example is Antennapedia: a gain-of-function allele causes legs to develop in the place of antennae.
In botany, Rolf Sattler has revised the concept of homeosis (replacement) by his emphasis on partial homeosis in addition to complete homeosis; this revision is now widely accepted.
Homeotic mutants in angiosperms are thought to be rare in the wild: in the annual plant Clarkia (Onagraceae), homeotic mutants are known where the petals are replaced by a second whorl of sepal-like organs, originating in a mutation of a single gene. The absence of lethal or de
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https://en.wikipedia.org/wiki/Streak
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Streak or streaking may refer to:
Streaking, running naked in a public place
Streaking or surfactant leaching in acrylic paints
Streaking (microbiology), a method of purifying micro-organisms
Streak (mineralogy), the color left by a mineral dragged across a rough surface
Streak (moth), in the family Geometridae
Streak (film), a 2008 film
Winning streak, consecutive wins in sport or gambling
Losing streak
The Streak (professional wrestling), a run of victories for The Undertaker at WrestleMania
The Streak (Easton High School Wrestling), a Pennsylvania, US, high-school streak
Iron man (sports streak), an athlete of unusual physical endurance
Hitting streak, in baseball, a consecutive amount of games in which a player appears and gets at least one base hit.
Dell Streak, tablet computer by Dell
Streak camera, device to measure short optical pulses
"The Streak" (song), a 1974 record by Ray Stevens
Archenteron, an indentation on a blastula
Heath Streak (1974–2023), Zimbabwean cricketer and cricket coach
Aero-Flight Streak, a late 1940s single engine civilian aircraft
Streak (company) is a private American company founded in 2011 and based in San Francisco, California
See also
Streaker (disambiguation)
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https://en.wikipedia.org/wiki/Robert%20Nalbandyan
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Robert M. Nalbandyan (, 1937–2002) was an Armenian chemist, the co-discoverer of photosynthetic protein plantacyanin, a pioneer in the field of free radicals, and a noted and prolific writer on various subjects in the field of chemistry.
Born in Yerevan, Armenia and educated at Moscow State University in Moscow, Russia, Nalbandyan lived and worked in Yerevan for most of his life, where he also headed a laboratory and lectured. He was recognized as one of Soviet Union's most prominent chemists, and in his research collaborated with fellow chemists in the USSR, US, Europe, and Australia. When the Armenian Soviet Socialist Republic struck for independence in 1989, Nalbandyan became a prominent critic of the nationalist movement, which he felt was foolhardy and was merely agitating the people for political gain. The energy shortage, economic woes, and virtual blockade experienced after independence seemed to justify his concerns. In 1996 he left the country and emigrated to the United States.
Primarily known in the scientific community for his research work with proteins, Nalbandyan was also recognized among his fellow scientists as a progressive thinker in other fields of chemistry, including neurochemistry.
References
1937 births
2002 deaths
Scientists from Yerevan
Moscow State University alumni
Armenian emigrants to the United States
Armenian chemists
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https://en.wikipedia.org/wiki/Lakatos%20Award
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The Lakatos Award is given annually for an outstanding contribution to the philosophy of science, widely interpreted. The contribution must be in the form of a monograph, co-authored or single-authored, and published in English during the previous six years. The award is in memory of the influential Hungarian philosopher of science and mathematics Imre Lakatos, whose tenure as Professor of Logic at the London School of Economics and Political Science (LSE) was cut short by his early and unexpected death. While administered by an international management committee organised from the LSE, it is independent of the LSE Department of Philosophy, Logic, and Scientific Method, with many of the committee's members being academics from other institutions. The value of the award, which has been endowed by the Latsis Foundation, is £10,000, and to take it up a successful candidate must visit the LSE and deliver a public lecture.
Selection
The award is administered by the following committee:
Professor Roman Frigg (Convenor, LSE)
Professor Richard Bradley (LSE)
Professor Hasok Chang (University of Cambridge)
Professor Nancy Cartwright (University of Durham)
Professor Kostas Gavroglu (University of Athens)
Professor Helen Longino (Stanford University)
Professor Samir Okasha (University of Bristol)
Professor Sabina Leonelli (University of Exeter)
The Committee makes the Award on the advice of an independent and anonymous panel of selectors.
Winners
The Award has so far been won by:
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https://en.wikipedia.org/wiki/Ciphertext%20stealing
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In cryptography, ciphertext stealing (CTS) is a general method of using a block cipher mode of operation that allows for processing of messages that are not evenly divisible into blocks without resulting in any expansion of the ciphertext, at the cost of slightly increased complexity.
General characteristics
Ciphertext stealing is a technique for encrypting plaintext using a block cipher, without padding the message to a multiple of the block size, so the ciphertext is the same size as the plaintext.
It does this by altering processing of the last two blocks of the message. The processing of all but the last two blocks is unchanged, but a portion of the second-to-last block's ciphertext is "stolen" to pad the last plaintext block. The padded final block is then encrypted as usual.
The final ciphertext, for the last two blocks, consists of the partial penultimate block (with the "stolen" portion omitted) plus the full final block, which are the same size as the original plaintext.
Decryption requires decrypting the final block first, then restoring the stolen ciphertext to the penultimate block, which can
then be decrypted as usual.
In principle any block-oriented block cipher mode of operation can be used, but stream-cipher-like modes can already be applied to messages of arbitrary length without padding, so they do not benefit from this technique. The common modes of operation that are coupled with ciphertext stealing are Electronic Codebook (ECB) and Cipher Block Ch
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https://en.wikipedia.org/wiki/Link%20%28knot%20theory%29
|
In mathematical knot theory, a link is a collection of knots which do not intersect, but which may be linked (or knotted) together. A knot can be described as a link with one component. Links and knots are studied in a branch of mathematics called knot theory. Implicit in this definition is that there is a trivial reference link, usually called the unlink, but the word is also sometimes used in context where there is no notion of a trivial link.
For example, a co-dimension 2 link in 3-dimensional space is a subspace of 3-dimensional Euclidean space (or often the 3-sphere) whose connected components are homeomorphic to circles.
The simplest nontrivial example of a link with more than one component is called the Hopf link, which consists of two circles (or unknots) linked together once. The circles in
the Borromean rings are collectively linked despite the fact that no two of them are directly linked. The Borromean rings thus form a Brunnian link and in fact constitute the simplest such link.
Generalizations
The notion of a link can be generalized in a number of ways.
General manifolds
Frequently the word link is used to describe any submanifold of the sphere diffeomorphic to a disjoint union of a finite number of spheres, .
In full generality, the word link is essentially the same as the word knot – the context is that one has a submanifold M of a manifold N (considered to be trivially embedded) and a non-trivial embedding of M in N, non-trivial in the sense that t
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https://en.wikipedia.org/wiki/Boolean%20data%20type
|
In computer science, the Boolean (sometimes shortened to Bool) is a data type that has one of two possible values (usually denoted true and false) which is intended to represent the two truth values of logic and Boolean algebra. It is named after George Boole, who first defined an algebraic system of logic in the mid 19th century. The Boolean data type is primarily associated with conditional statements, which allow different actions by changing control flow depending on whether a programmer-specified Boolean condition evaluates to true or false. It is a special case of a more general logical data type—logic does not always need to be Boolean (see probabilistic logic).
Generalities
In programming languages with a built-in Boolean data type, such as Pascal and Java, the comparison operators such as > and ≠ are usually defined to return a Boolean value. Conditional and iterative commands may be defined to test Boolean-valued expressions.
Languages with no explicit Boolean data type, like C90 and Lisp, may still represent truth values by some other data type. Common Lisp uses an empty list for false, and any other value for true. The C programming language uses an integer type, where relational expressions like i > j and logical expressions connected by && and || are defined to have value 1 if true and 0 if false, whereas the test parts of if, while, for, etc., treat any non-zero value as true. Indeed, a Boolean variable may be regarded (and implemented) as a numerical varia
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https://en.wikipedia.org/wiki/Potts%20model
|
In statistical mechanics, the Potts model, a generalization of the Ising model, is a model of interacting spins on a crystalline lattice. By studying the Potts model, one may gain insight into the behaviour of ferromagnets and certain other phenomena of solid-state physics. The strength of the Potts model is not so much that it models these physical systems well; it is rather that the one-dimensional case is exactly solvable, and that it has a rich mathematical formulation that has been studied extensively.
The model is named after Renfrey Potts, who described the model near the end of his 1951 Ph.D. thesis. The model was related to the "planar Potts" or "clock model", which was suggested to him by his advisor, Cyril Domb. The four-state Potts model is sometimes known as the Ashkin–Teller model, after Julius Ashkin and Edward Teller, who considered an equivalent model in 1943.
The Potts model is related to, and generalized by, several other models, including the XY model, the Heisenberg model and the N-vector model. The infinite-range Potts model is known as the Kac model. When the spins are taken to interact in a non-Abelian manner, the model is related to the flux tube model, which is used to discuss confinement in quantum chromodynamics. Generalizations of the Potts model have also been used to model grain growth in metals, coarsening in foams, and statistical properties of proteins. A further generalization of these methods by James Glazier and Francois Graner, known a
|
https://en.wikipedia.org/wiki/Robert%20J.%20Lang
|
Robert James Lang (born May 4, 1961) is an American physicist who is also one of the foremost origami artists and theorists in the world. He is known for his complex and elegant designs, most notably of insects and animals. He has studied the mathematics of origami and used computers to study the theories behind origami. He has made great advances in making real-world applications of origami to engineering problems.
Education and early occupation
Lang was born in Dayton, Ohio, and grew up in Atlanta, Georgia. Lang studied electrical engineering at the California Institute of Technology, where he met his wife-to-be, Diane. He earned a master's degree in electrical engineering at Stanford University in 1983, and returned to Caltech for a Ph.D. in applied physics, with a dissertation titled Semiconductor Lasers: New Geometries and Spectral Properties.
Lang began work for NASA's Jet Propulsion Laboratory in 1988. Lang also worked as a research scientist for Spectra Diode Labs of San Jose, California, and then at JDS Uniphase, also of San Jose.
Lang has authored or co-authored over 80 publications on semiconductor lasers, optics, and integrated optoelectronics, and holds 46 patents in these fields. In 2001, Lang left the engineering field to be a full-time origami artist and consultant. However, he still maintains ties to his physics background: he was the editor-in-chief of the IEEE Journal of Quantum Electronics from 2007 to 2010, and has done part-time laser consulting for
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https://en.wikipedia.org/wiki/Benzoylecgonine
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Benzoylecgonine is the main metabolite of cocaine, formed by the liver and excreted in the urine. It is the compound tested for in most cocaine urine drug screens and in wastewater screenings for cocaine use.
Biochemistry and physiology
Chemically, benzoylecgonine is the benzoate ester of ecgonine. It is a primary metabolite of cocaine, and is pharmacologically inactive. It is the corresponding carboxylic acid of cocaine, its methyl ester. It is formed in the liver by the metabolism of cocaine by hydrolysis, catalysed by carboxylesterases, and subsequently excreted in the urine.
Urinalysis
Benzoylecgonine is the compound tested for in most substantive cocaine drug urinalyses.
Presence in drinking water
Benzoylecgonine is sometimes found in drinking water supplies. In 2005, scientists found surprisingly large quantities of benzoylecgonine in Italy's Po River and used its concentration to estimate the number of cocaine users in the region. In 2006, a similar study was performed in the Swiss ski town of Saint-Moritz using wastewater to estimate the daily cocaine consumption of the population. A study done in the United Kingdom found traces of benzoylecgonine in the country's drinking water supply, along with carbamazepine (an anticonvulsant) and ibuprofen (a common non-steroidal anti-inflammatory drug), although the study noted that the amount of each compound present was several orders of magnitude lower than the therapeutic dose and therefore did not pose a risk to the pop
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https://en.wikipedia.org/wiki/A.%20A.%20Krishnaswami%20Ayyangar
|
A. A. Krishnaswami Ayyangar (1892–1953) was an Indian mathematician. He received his M.A. in Mathematics at the age of 18 from Pachaiyappa's College, and subsequently taught mathematics there. In 1918, he joined the mathematics department of the University of Mysore and retired from there in 1947. He was born in a Tamil Brahmin family. He died in June 1953. He was the father of the Kannada poet and scholar A. K. Ramanujan.
Works
Ayyangar had a number of publications, including an article on the Chakravala method where he showed how the method differed from the method of continued fractions. He pointed out that this point was missed by André Weil, who thought that the Chakravala method was only an "experimental fact" to the Indians and attributed general proofs to Pierre de Fermat and Joseph-Louis Lagrange.
Professor Subhash Kak of Louisiana State University, Baton Rouge first noted that Ayyangar's presentations of the work of other Indian mathematicians was unique, and was instrumental in bringing it to the notice of the scientific community.
References
External links
Brief life and some papers
1892 births
1953 deaths
20th-century Indian mathematicians
Academic staff of the University of Mysore
Scientists from Karnataka
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https://en.wikipedia.org/wiki/First-class%20function
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In computer science, a programming language is said to have first-class functions if it treats functions as first-class citizens. This means the language supports passing functions as arguments to other functions, returning them as the values from other functions, and assigning them to variables or storing them in data structures. Some programming language theorists require support for anonymous functions (function literals) as well. In languages with first-class functions, the names of functions do not have any special status; they are treated like ordinary variables with a function type. The term was coined by Christopher Strachey in the context of "functions as first-class citizens" in the mid-1960s.
First-class functions are a necessity for the functional programming style, in which the use of higher-order functions is a standard practice. A simple example of a higher-ordered function is the map function, which takes, as its arguments, a function and a list, and returns the list formed by applying the function to each member of the list. For a language to support map, it must support passing a function as an argument.
There are certain implementation difficulties in passing functions as arguments or returning them as results, especially in the presence of non-local variables introduced in nested and anonymous functions. Historically, these were termed the funarg problems, the name coming from "function argument". In early imperative languages these problems were avoided
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https://en.wikipedia.org/wiki/Protein%20kinase%20C
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In cell biology, Protein kinase C, commonly abbreviated to PKC (EC 2.7.11.13), is a family of protein kinase enzymes that are involved in controlling the function of other proteins through the phosphorylation of hydroxyl groups of serine and threonine amino acid residues on these proteins, or a member of this family. PKC enzymes in turn are activated by signals such as increases in the concentration of diacylglycerol (DAG) or calcium ions (Ca2+). Hence PKC enzymes play important roles in several signal transduction cascades.
In biochemistry, the PKC family consists of fifteen isozymes in humans. They are divided into three subfamilies, based on their second messenger requirements: conventional (or classical), novel, and atypical. Conventional (c)PKCs contain the isoforms α, βI, βII, and γ. These require Ca2+, DAG, and a phospholipid such as phosphatidylserine for activation. Novel (n)PKCs include the δ, ε, η, and θ isoforms, and require DAG, but do not require Ca2+ for activation. Thus, conventional and novel PKCs are activated through the same signal transduction pathway as phospholipase C. On the other hand, atypical (a)PKCs (including protein kinase Mζ and ι / λ isoforms) require neither Ca2+ nor diacylglycerol for activation. The term "protein kinase C" usually refers to the entire family of isoforms. The different classes of PKCs found in jawed vertebrates originate from 5 ancestral PKC family members (PKN, aPKC, cPKC, nPKCE, nPKCD) that expanded due to genome duplicati
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https://en.wikipedia.org/wiki/Meyer
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Meyer may refer to:
People
Meyer (surname), listing people so named
Meyer (name), a list of people and fictional characters with the name
Companies
Meyer Burger, a Swiss mechanical engineering company
Meyer Corporation
Meyer Sound Laboratories
Meyer Turku, a Finnish shipbuilding company
Behn Meyer, a German chemical company
Fred Meyer, an American hypermarket chain and subsidiary of Kroger
Fred Meyer Jewelers
Places
United States
Meyer, Illinois, an unincorporated community in Adams County, Illinois
Meyer, Franklin County, Illinois, an unincorporated community in Franklin County, Illinois
Meyer, Iowa, in Mitchell County, Iowa
Myers, Montana (also spelled Meyer), an unincorporated community in Treasure County
Meyer Township, Michigan
Other
Meyer House (disambiguation), multiple buildings in the U.S.
Meyer locomotive
Meyer Theatre, an historic theater in Wisconsin, U.S.
USS Meyer (DD-279), a Clemson-class destroyer in the United States Navy
See also
Justice Meyer (disambiguation)
Von Meyer
Myer (disambiguation)
Meyr (disambiguation)
Meier
Meijer (surname)
Meir (disambiguation)
Mair (disambiguation)
Mayer (disambiguation)
Maier
Mayr
Meyers
Myers
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https://en.wikipedia.org/wiki/Knot%20group
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In mathematics, a knot is an embedding of a circle into 3-dimensional Euclidean space. The knot group of a knot K is defined as the fundamental group of the knot complement of K in R3,
Other conventions consider knots to be embedded in the 3-sphere, in which case the knot group is the fundamental group of its complement in .
Properties
Two equivalent knots have isomorphic knot groups, so the knot group is a knot invariant and can be used to distinguish between certain pairs of inequivalent knots. This is because an equivalence between two knots is a self-homeomorphism of that is isotopic to the identity and sends the first knot onto the second. Such a homeomorphism restricts onto a homeomorphism of the complements of the knots, and this restricted homeomorphism induces an isomorphism of fundamental groups. However, it is possible for two inequivalent knots to have isomorphic knot groups (see below for an example).
The abelianization of a knot group is always isomorphic to the infinite cyclic group Z; this follows because the abelianization agrees with the first homology group, which can be easily computed.
The knot group (or fundamental group of an oriented link in general) can be computed in the Wirtinger presentation by a relatively simple algorithm.
Examples
The unknot has knot group isomorphic to Z.
The trefoil knot has knot group isomorphic to the braid group B3. This group has the presentation
or
A (p,q)-torus knot has knot group with presentation
The f
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https://en.wikipedia.org/wiki/Michael%20Heath
|
Michael Heath may refer to:
Mike Heath (baseball) (born 1955), baseball player
Michael Heath (cartoonist) (born 1935), British strip cartoonist and illustrator
Michael Heath (computer scientist) (born 1946), computer scientist who specializes in scientific computing
Mike Heath (swimmer) (born 1964), former American Olympic swimmer
Michael Heath (Paralympic swimmer) (born 1989), Canadian Paralympic swimmer
Michael Heath, the Recorder of Lincoln
See also
Mickey Heath (1903–1986), baseball player
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https://en.wikipedia.org/wiki/Chromism
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In chemistry, chromism is a process that induces a change, often reversible, in the colors of compounds. In most cases, chromism is based on a change in the electron states of molecules, especially the π- or d-electron state, so this phenomenon is induced by various external stimuli which can alter the electron density of substances. It is known that there are many natural compounds that have chromism, and many artificial compounds with specific chromism have been synthesized to date. It is usually synonymous with chromotropism, the (reversible) change in color of a substance due to the physical and chemical properties of its ambient surrounding medium, such as temperature and pressure, light, solvent, and presence of ions and electrons.
Chromism is classified by what kind of stimuli are used. Examples of the major kinds of chromism are as follows.
thermochromism is chromism that is induced by heat, that is, a change of temperature. This is the most common chromism of all.
photochromism is induced by light irradiation. This phenomenon is based on the isomerization between two different molecular structures, light-induced formation of color centers in crystals, precipitation of metal particles in a glass, or other mechanisms.
electrochromism is induced by the gain and loss of electrons. This phenomenon occurs in compounds with redox active sites, such as metal ions or organic radicals.
solvatochromism depends on the polarity of the solvent. Most solvatochromic compounds a
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https://en.wikipedia.org/wiki/Precision%20%28computer%20science%29
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In computer science, the precision of a numerical quantity is a measure of the detail in which the quantity is expressed. This is usually measured in bits, but sometimes in decimal digits. It is related to precision in mathematics, which describes the number of digits that are used to express a value.
Some of the standardized precision formats are
Half-precision floating-point format
Single-precision floating-point format
Double-precision floating-point format
Quadruple-precision floating-point format
Octuple-precision floating-point format
Of these, octuple-precision format is rarely used. The single- and double-precision formats are most widely used and supported on nearly all platforms. The use of half-precision format has been increasing especially in the field of machine learning since many machine learning algorithms are inherently error-tolerant.
Rounding error
Precision is often the source of rounding errors in computation. The number of bits used to store a number will often cause some loss of accuracy. An example would be to store "sin(0.1)" in IEEE single precision floating point standard. The error is then often magnified as subsequent computations are made using the data (although it can also be reduced).
See also
Arbitrary-precision arithmetic
Extended precision
Granularity
IEEE754 (IEEE floating point standard)
Integer (computer science)
Significant figures
Truncation
Approximate computing
References
Computer data
Approximations
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https://en.wikipedia.org/wiki/Fr%C3%A9d%C3%A9ric%20Lepied
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Frédéric Lepied (born 1967) is a French computer engineer, and was the CTO of Mandriva until January 2006.
Biography
Born in 1967, Frédéric Lepied took an early interest in computer science and was educated at the Bréguet school in Noisy-le-Grand, France.
In 1999, he joined the Mandrakesoft Research and Development team. He was known as the author of rpmlint, an RPM packages checker (similar to Debian's lintian program), and the maintainer of several core packages, including XFree86 and the initscripts. At that time he wrote an O'Reilly book on CVS (2000) and maintained the wacom tablet driver in XFree86 and in X.Org (2001). He then spent one year in Canada in the Mandrakesoft Montreal office, and became Mandrakesoft CTO when he came back to France in 2002.
Frédéric Lepied left Mandriva on February 3, 2006. He then joined Intel Corporation to manage Software manufacturers relationships. Late 2008, he joined Splitted Desktop Systems an innovative hardware company, as chief of strategy. In 2013, he became VP Software Engineering at eNovance before joining Red Hat in 2015.
References
Sources
1967 births
Living people
French computer scientists
Free software programmers
French computer programmers
French businesspeople
Mandriva Linux
Debian people
Intel people
Red Hat people
Red Hat employees
Emacs
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https://en.wikipedia.org/wiki/Interhalogen
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In chemistry, an interhalogen compound is a molecule which contains two or more different halogen atoms (fluorine, chlorine, bromine, iodine, or astatine) and no atoms of elements from any other group.
Most interhalogen compounds known are binary (composed of only two distinct elements). Their formulae are generally , where n = 1, 3, 5 or 7, and X is the less electronegative of the two halogens. The value of n in interhalogens is always odd, because of the odd valence of halogens. They are all prone to hydrolysis, and ionize to give rise to polyhalogen ions. Those formed with astatine have a very short half-life due to astatine being intensely radioactive.
No interhalogen compounds containing three or more different halogens are definitely known, although a few books claim that and have been obtained, and theoretical studies seem to indicate that some compounds in the series are barely stable.
Some interhalogens, such as , , and , are good halogenating agents. is too reactive to generate fluorine. Beyond that, iodine monochloride has several applications, including helping to measure the saturation of fats and oils, and as a catalyst for some reactions. A number of interhalogens, including , are used to form polyhalides.
Similar compounds exist with various pseudohalogens, such as the halogen azides (, , , and ) and cyanogen halides (, , , and ).
Types of interhalogens
Diatomic interhalogens
The interhalogens of form XY have physical properties intermediate betwee
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https://en.wikipedia.org/wiki/Sanford%20Jackson
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Sanford Jackson was a Canadian biochemist.
Jackson graduated from the University of Toronto in chemical engineering and pathological chemistry. He was research biochemist and biochemist-in-chief at the Toronto Hospital for Sick Children 1937–1974.
Jackson was a founding member of the Canadian Society of Clinical Chemists and the Ontario Society of Clinical Chemists. He invented the bilirubinometer, which allowed more accurate measurement of serum bilirubin in infants and children.
Jackson died 4 September 2000 at age 91.
References
External links
Professor Emeritus Sanford Jackson
Year of birth missing
Canadian biochemists
University of Toronto alumni
Academic staff of the University of Toronto
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https://en.wikipedia.org/wiki/Raymond%20Davis
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Raymond Davis may refer to:
Raymond Davis Jr. (1914–2006), American physicist and chemist, Nobel laureate in physics
Ray Davis (American football) (born 1999), American football player
Ray Davis (musician) (1940–2005), member of The Parliaments, Parliament, Funkadelic, and The Temptations
Ray Davis (businessman), chief executive officer of Energy Transfer Partners and owner of the Texas Rangers of Major League Baseball
Raymond Allen Davis (born 1974), American CIA contractor accused of double murder in Pakistan in 2011
Raymond E. Davis (1885–1965), U.S. Navy sailor and 1906 recipient of the U.S. Medal of Honor
Raymond G. Davis (1915–2003), U.S. Marine Corps general and 1950 recipient of the U.S. Medal of Honor
Wallace Ray Davis (1949–2007), televangelist and owner of Affiliated Media Group
Ray E. Davis, football and baseball coach at Louisiana Tech in 1939
Raymond Cazallis Davis (1836–1919), chief librarian at the University of Michigan
See also
Raymond Davies (disambiguation)
Ray Davies (born 1944), frontman of The Kinks
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https://en.wikipedia.org/wiki/Quenching
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In materials science, quenching is the rapid cooling of a workpiece in water, oil, polymer, air, or other fluids to obtain certain material properties. A type of heat treating, quenching prevents undesired low-temperature processes, such as phase transformations, from occurring. It does this by reducing the window of time during which these undesired reactions are both thermodynamically favorable, and kinetically accessible; for instance, quenching can reduce the crystal grain size of both metallic and plastic materials, increasing their hardness.
In metallurgy, quenching is most commonly used to harden steel by inducing a martensite transformation, where the steel must be rapidly cooled through its eutectoid point, the temperature at which austenite becomes unstable. In steel alloyed with metals such as nickel and manganese, the eutectoid temperature becomes much lower, but the kinetic barriers to phase transformation remain the same. This allows quenching to start at a lower temperature, making the process much easier. High-speed steel also has added tungsten, which serves to raise kinetic barriers, which among other effects gives material properties (hardness and abrasion resistance) as though the workpiece had been cooled more rapidly than it really has. Even cooling such alloys slowly in air has most of the desired effects of quenching; high-speed steel weakens much less from heat cycling due to high-speed cutting.
Extremely rapid cooling can prevent the formation of a
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https://en.wikipedia.org/wiki/Boltzmann%20machine
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A Boltzmann machine (also called Sherrington–Kirkpatrick model with external field or stochastic Ising–Lenz–Little model) is a stochastic spin-glass model with an external field, i.e., a Sherrington–Kirkpatrick model, that is a stochastic Ising model. It is a statistical physics technique applied in the context of cognitive science. It is also classified as a Markov random field.
Boltzmann machines are theoretically intriguing because of the locality and Hebbian nature of their training algorithm (being trained by Hebb's rule), and because of their parallelism and the resemblance of their dynamics to simple physical processes. Boltzmann machines with unconstrained connectivity have not been proven useful for practical problems in machine learning or inference, but if the connectivity is properly constrained, the learning can be made efficient enough to be useful for practical problems.
They are named after the Boltzmann distribution in statistical mechanics, which is used in their sampling function. They were heavily popularized and promoted by Geoffrey Hinton, Terry Sejnowski and Yann LeCun in cognitive sciences communities and in machine learning. As a more general class within machine learning these models are called "energy based models" (EBM), because Hamiltonians of spin glasses are used as a starting point to define the learning task.
Structure
A Boltzmann machine, like a Sherrington–Kirkpatrick model, is a network of units with a total "energy" (Hamiltonian) de
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https://en.wikipedia.org/wiki/David%20J.%20Simms
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David John Simms (13 January 1933 – 24 June 2018) was an Indian-born Irish mathematician who was a Fellow Emeritus and former Associate Professor of Mathematics at Trinity College, Dublin. Born in Sankeshwar, Mysore (the state now known as Karnataka), India, he specialized in differential geometry and geometric quantisation. He was a member of the Royal Irish Academy from 1978 and was a member of the Editorial Board of the journal Mathematical Proceedings of the Royal Irish Academy.
Academic career
Simms completed his undergraduate degree in Mathematics in Trinity College Dublin, graduating in 1955. He was elected a Scholar of the College in 1952, when he was just in the first year of his degree, a notable achievement. He went on to do a Ph.D. in the University of Cambridge under W. V. D. Hodge. Simms lectured in Glasgow University before returning to Trinity. He served as head of the Department of Pure and Applied Mathematics from 1991 to 1998.
Simms' research interests included differential geometry and geometric quantisation.
Books and select publications
Lie Groups and Quantum Mechanics, Springer Lecture Notes in Mathematics Number 52, 1968
Lectures on Geometric Quantization, (with N.M.J. Woodhouse) Springer Lecture Notes in Physics Number 53, 1976 professional papers.
Geometric quantization of energy levels in the Kepler problem, D.J. Simms - Symposia Mathematica, 1974
David Simms was a member of the Royal Irish Academy since 1978. He was a member of the Editorial
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https://en.wikipedia.org/wiki/Rachel%20Carson%20College
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Rachel Carson College is a residential college at the University of California, Santa Cruz. Named in honor of conservationist Rachel Carson, it is on the west side of campus, north of Oakes College and southeast of Porter College. The current provost of the college is Professor Sue Carter, also a faculty member of UCSC's Physics Department. The theme of its freshman core course is Environment and Society.
History
Rachel Carson College was founded in 1972 as College Eight at the current location of the Kerr Hall lecture building. Before it moved to its present location in 1990, College Eight was the only UCSC college that did not have its own on-campus housing; residential students were then housed at the Porter College residence halls. At the time, its focus was on transfer students, who are usually less likely to live on campus than students on a traditional four-year course.
On September 15, 2016, it was announced that the former College Eight would be named Rachel Carson College, with the help of an endowment from the Helen and Will Webster Foundation.
Freshman core class
Rachel Carson College's freshman core class, Environment and Society, "examines education, identity, nature, community, livelihood, and livability at local and national levels as contemporary global transformations affect them." (All Rachel Carson College freshmen must take it, but transfer students are exempt if they have more than 45 credits.) The course has been expanded to a year, the first quart
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https://en.wikipedia.org/wiki/Exponential%20formula
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In combinatorial mathematics, the exponential formula (called the polymer expansion in physics) states that the exponential generating function for structures on finite sets is the exponential of the exponential generating function for connected structures.
The exponential formula is a power-series version of a special case of Faà di Bruno's formula.
Algebraic statement
Here is a purely algebraic statement, as a first introduction to the combinatorial use of the formula.
For any formal power series of the form
we have
where
and the index runs through the list of all partitions of the set
. (When the product is empty and by definition equals .)
Formula in other expressions
One can write the formula in the following form:
and thus
where is the th complete Bell polynomial.
Alternatively, the exponential formula can also be written using the cycle index of the symmetric group, as follows:where stands for the cycle index polynomial, for the symmetric group defined as:and denotes the number of cycles of of size . This is a consequence of the general relation between and Bell polynomials:
The combinatorial formula
In applications, the numbers count the number of some sort of "connected" structure on an -point set, and the numbers count the number of (possibly disconnected) structures. The numbers count the number of isomorphism classes of structures on points, with each structure being weighted by the reciprocal of its automorphism group, and the numbers coun
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https://en.wikipedia.org/wiki/ICR
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ICR may refer to:
Biology
Idiopathic condylar resorption, a temporomandibular joint disorder
Immunological constant of rejection, Immunology concept relating to tissue rejection
Implanted cardiac resynchronization device, in cardiology
Imprinting Control Region, genetic imprinting
Electronics and physics
Inductance (L), Capacitance (C), Resistance (R), see LCR meter and RLC circuit
Instant centre of rotation, the point in a body undergoing planar movement that has zero velocity at a particular time
Intelligent character recognition, advanced OCR
Ion cyclotron resonance, a physics phenomenon in cyclotron particle acceleration
Organizations
Catholic University of Rennes (Institut catholique de Rennes), a French Catholic university
Institute for Centrifugal Research, imaginary company created by Till Nowak as the impetus behind The Centrifuge Brain Project
Institute for Comparative Research in Human and Social Sciences, a Japanese institution in humanities and social sciences
Institute for Creation Research, a creationist organization in Dallas, Texas
Institute of Cancer Research, a college within the University of London
Institute of Cetacean Research, a Japanese institution
International Care & Relief, international development charity
International Centre of Reconstruction
International Rescue Committee, a global humanitarian, relief, and refugee-assistance non-government agency
Iraqi Council of Representatives, a political council of Iraq
Central Instit
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https://en.wikipedia.org/wiki/Jacqueline%20Barton
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Jacqueline K. Barton (born May 7, 1952 New York City, NY), is an American chemist. She worked as a professor of chemistry at Hunter College (1980–82), and at Columbia University (1983–89) before joining the California Institute of Technology. In 1997 she became the Arthur and Marian Hanisch Memorial Professor of Chemistry and from 2009 to 2019, the Norman Davidson Leadership Chair of the Division of Chemistry and Chemical Engineering at Caltech. She currently is the John G. Kirkwood and Arthur A. Noyes Professor of Chemistry.
Barton studies the chemical and physical properties of DNA and their roles in biological activities. The primary focus of her research is transverse electron transport along double-stranded DNA, its implications in the biology of DNA damage and repair, and its potential for materials sciences applications such as targeted chemotherapeutic treatments for cancer. Among many other awards, Barton has received the 2011 National Medal of Science and the 2015 Priestley Medal.
Early life and education
Jacqueline Ann Kapelman was born on May 7, 1952, in New York City. Her father served in the Assembly for nearly a decade before serving as a trial judge in the New York Supreme Court next two decades. Her father was one of the trial judges in the Son of Sam serial murder case.
Jacqueline Kapelman attended Riverdale Country School for Girls in Riverdale, New York, where her math teacher, Mrs. Rosenberg, insisted that she be allowed to take calculus at the boy
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https://en.wikipedia.org/wiki/List%20of%20mathematical%20knots%20and%20links
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This article contains a list of mathematical knots and links. See also list of knots, list of geometric topology topics.
Knots
Prime knots
01 knot/Unknot - a simple un-knotted closed loop
31 knot/Trefoil knot - (2,3)-torus knot, the two loose ends of a common overhand knot joined together
41 knot/Figure-eight knot (mathematics) - a prime knot with a crossing number four
51 knot/Cinquefoil knot, (5,2)-torus knot, Solomon's seal knot, pentafoil knot - a prime knot with crossing number five which can be arranged as a {5/2} star polygon (pentagram)
52 knot/Three-twist knot - the twist knot with three-half twists
61 knot/Stevedore knot (mathematics) - a prime knot with crossing number six, it can also be described as a twist knot with four twists
62 knot - a prime knot with crossing number six
63 knot - a prime knot with crossing number six
71 knot, septafoil knot, (7,2)-torus knot - a prime knot with crossing number seven, which can be arranged as a {7/2} star polygon (heptagram)
74 knot, "endless knot"
818 knot, "carrick mat"
10161/10162, known as the Perko pair; this was a single knot listed twice in Dale Rolfsen's knot table; the duplication was discovered by Kenneth Perko
12n242/(−2,3,7) pretzel knot
(p, q)-torus knot - a special kind of knot that lies on the surface of an unknotted torus in R3
Composite
Square knot (mathematics) - a composite knot obtained by taking the connected sum of a trefoil knot with its reflection
Granny knot (mathematics) - a composite knot obtai
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https://en.wikipedia.org/wiki/Toroidal
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Toroidal describes something which resembles or relates to a torus or toroid:
Mathematics
Torus
Toroid, a surface of revolution which resembles a torus
Toroidal polyhedron
Toroidal coordinates, a three-dimensional orthogonal coordinate system
Toroidal and poloidal coordinates, directions relative to a torus of reference
Toroidal graph, a graph whose vertices can be placed on a torus such that no edges cross
Toroidal grid network, where an n-dimensional grid network is connected circularly in more than one dimension
Engineering
Toroidal inductors and transformers, a type of electrical device
Toroidal and poloidal, directions in magnetohydrodynamics
Toroidal engine, an internal combustion engine with pistons that rotate within a toroidal space
Toroidal CVT, a type of continuously variable transmission
Toroidal reflector, a parabolic reflector which has a different focal distance depending on the angle of the mirror
Toroidal propeller, an efficient propeller design
Other uses
Toroidal ring model in theoretical physics
Vortex ring, also known as a toroidal vortex; a toroidal flow in fluid mechanics
See also
Atoroidal
Torus (disambiguation)
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https://en.wikipedia.org/wiki/Tamagawa%20number
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In mathematics, the Tamagawa number of a semisimple algebraic group defined over a global field is the measure of , where is the adele ring of . Tamagawa numbers were introduced by , and named after him by .
Tsuneo Tamagawa's observation was that, starting from an invariant differential form ω on , defined over , the measure involved was well-defined: while could be replaced by with a non-zero element of , the product formula for valuations in is reflected by the independence from of the measure of the quotient, for the product measure constructed from on each effective factor. The computation of Tamagawa numbers for semisimple groups contains important parts of classical quadratic form theory.
Definition
Let be a global field, its ring of adeles, and a semisimple algebraic group defined over .
Choose Haar measures on the completions such that has volume 1 for all but finitely many places . These then induce a Haar measure on , which we further assume is normalized so that has volume 1 with respect to the induced quotient measure.
The Tamagawa measure on the adelic algebraic group is now defined as follows. Take a left-invariant -form on defined over , where is the dimension of . This, together with the above choices of Haar measure on the , induces Haar measures on for all places of . As is semisimple, the product of these measures yields a Haar measure on , called the Tamagawa measure. The Tamagawa measure does not depend on the choice of ω, nor o
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https://en.wikipedia.org/wiki/Zero%20matrix
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In mathematics, particularly linear algebra, a zero matrix or null matrix is a matrix all of whose entries are zero. It also serves as the additive identity of the additive group of matrices, and is denoted by the symbol or followed by subscripts corresponding to the dimension of the matrix as the context sees fit. Some examples of zero matrices are
Properties
The set of matrices with entries in a ring K forms a ring . The zero matrix in is the matrix with all entries equal to , where is the additive identity in K.
The zero matrix is the additive identity in . That is, for all it satisfies the equation
There is exactly one zero matrix of any given dimension m×n (with entries from a given ring), so when the context is clear, one often refers to the zero matrix. In general, the zero element of a ring is unique, and is typically denoted by 0 without any subscript indicating the parent ring. Hence the examples above represent zero matrices over any ring.
The zero matrix also represents the linear transformation which sends all the vectors to the zero vector. It is idempotent, meaning that when it is multiplied by itself, the result is itself.
The zero matrix is the only matrix whose rank is 0.
Occurrences
The mortal matrix problem is the problem of determining, given a finite set of n × n matrices with integer entries, whether they can be multiplied in some order, possibly with repetition, to yield the zero matrix. This is known to be undecidable for a set of
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https://en.wikipedia.org/wiki/Charge-transfer%20complex
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In chemistry, a charge-transfer (CT) complex or electron-donor-acceptor complex describes a type of supramolecular assembly of two or more molecules or ions. The assembly consists of two molecules that self-attract through electrostatic forces, i.e., one has at least partial negative charge and the partner has partial positive charge, referred to respectively as the electron acceptor and electron donor. In some cases, the degree of charge transfer is "complete", such that the CT complex can be classified as a salt. In other cases, the charge-transfer association is weak, and the interaction can be disrupted easily by polar solvents.
Examples
Electron donor-acceptor complexes
A number of organic compounds form charge-transfer complex, which are often described as electron-donor-acceptor complexes (EDA complexes). Typical acceptors are nitrobenzenes or tetracyanoethylene (TCNE). The strength of their interaction with electron donors correlates with the ionization potentials of the components. For TCNE, the stability constants (L/mol) for its complexes with benzene derivatives correlates with the number of methyl groups: benzene (0.128), 1,3,5-trimethylbenzene (1.11), 1,2,4,5-tetramethylbenzene (3.4), and hexamethylbenzene (16.8).
1,3,5-Trinitrobenzene and related polynitrated aromatic compounds, being electron-deficient, form charge-transfer complexes with many arenes. Such complexes form upon crystallization, but often dissociate in solution to the components. Char
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https://en.wikipedia.org/wiki/Jared%20Cohon
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Jared Leigh Cohon (born October 7, 1947) served as the eighth president of Carnegie Mellon University in Pittsburgh, Pennsylvania, United States. he is a University Professor in the Carnegie Mellon College of Engineering.
He holds a BS in Civil Engineering from the University of Pennsylvania and MS and PhD degrees in Civil and Environmental Engineering from Massachusetts Institute of Technology, earned in 1972 and 1973, respectively.
Prior to Carnegie Mellon, Cohon was the Dean of the School of Forestry and Environmental Studies and professor of environmental systems analysis at Yale University from 1992 to 1997 and was a faculty member in the Department of Geography and Environmental Engineering and Assistant and Associate Dean of Engineering and Vice Provost for Research at Johns Hopkins University from 1973 to 1992.
Cohon stepped down from his position as President of Carnegie Mellon in 2013 and returned to the faculty as a University Professor in the Departments of Civil and Environmental Engineering and Engineering and Public Policy and director of the Wilton E. Scott Institute for Energy Innovation. In 2014, Carnegie Mellon announced that the University Center would be renamed in honor of President Cohon and will be called the Cohon University Center.
Cohon was elected a member of the National Academy of Engineering (2012) for contributions to environmental systems analysis and national policy and leadership in higher education.
References
External links
Preside
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https://en.wikipedia.org/wiki/Markov%20blanket
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In statistics and machine learning, when one wants to infer a random variable with a set of variables, usually a subset is enough, and other variables are useless. Such a subset that contains all the useful information is called a Markov blanket. If a Markov blanket is minimal, meaning that it cannot drop any variable without losing information, it is called a Markov boundary. Identifying a Markov blanket or a Markov boundary helps to extract useful features. The terms of Markov blanket and Markov boundary were coined by Judea Pearl in 1988. A Markov blanket can be constituted by a set of Markov chains.
Markov blanket
A Markov blanket of a random variable in a random variable set is any subset of , conditioned on which other variables are independent with :
It means that contains at least all the information one needs to infer , where the variables in are redundant.
In general, a given Markov blanket is not unique. Any set in that contains a Markov blanket is also a Markov blanket itself. Specifically, is a Markov blanket of in .
Markov boundary
A Markov boundary of in is a subset of , that itself is a Markov blanket of , but any proper subset of is not a Markov blanket of . In other words, a Markov boundary is a minimal Markov blanket.
The Markov boundary of a node in a Bayesian network is the set of nodes composed of 's parents, 's children, and 's children's other parents. In a Markov random field, the Markov boundary for a node is the set of its neig
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https://en.wikipedia.org/wiki/Chirality%20%28mathematics%29
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In geometry, a figure is chiral (and said to have chirality) if it is not identical to its mirror image, or, more precisely, if it cannot be mapped to its mirror image by rotations and translations alone. An object that is not chiral is said to be achiral.
A chiral object and its mirror image are said to be enantiomorphs. The word chirality is derived from the Greek (cheir), the hand, the most familiar chiral object; the word enantiomorph stems from the Greek (enantios) 'opposite' + (morphe) 'form'.
Examples
Some chiral three-dimensional objects, such as the helix, can be assigned a right or left handedness, according to the right-hand rule.
Many other familiar objects exhibit the same chiral symmetry of the human body, such as gloves and shoes. Right shoes differ from left shoes only by being mirror images of each other. In contrast thin gloves may not be considered chiral if you can wear them inside-out.
The J, L, S and Z-shaped tetrominoes of the popular video game Tetris also exhibit chirality, but only in a two-dimensional space. Individually they contain no mirror symmetry in the plane.
Chirality and symmetry group
A figure is achiral if and only if its symmetry group contains at least one orientation-reversing isometry. (In Euclidean geometry any isometry can be written as with an orthogonal matrix and a vector . The determinant of is either 1 or −1 then. If it is −1 the isometry is orientation-reversing, otherwise it is orientation-preserving.
A general d
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https://en.wikipedia.org/wiki/Chirality%20%28chemistry%29
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In chemistry, a molecule or ion is called chiral () if it cannot be superposed on its mirror image by any combination of rotations, translations, and some conformational changes. This geometric property is called chirality (). The terms are derived from Ancient Greek (cheir) 'hand'; which is the canonical example of an object with this property.
A chiral molecule or ion exists in two stereoisomers that are mirror images of each other, called enantiomers; they are often distinguished as either "right-handed" or "left-handed" by their absolute configuration or some other criterion. The two enantiomers have the same chemical properties, except when reacting with other chiral compounds. They also have the same physical properties, except that they often have opposite optical activities. A homogeneous mixture of the two enantiomers in equal parts is said to be racemic, and it usually differs chemically and physically from the pure enantiomers.
Chiral molecules will usually have a stereogenic element from which chirality arises. The most common type of stereogenic element is a stereogenic center, or stereocenter. In the case of organic compounds, stereocenters most frequently take the form of a carbon atom with four distinct groups attached to it in a tetrahedral geometry. A given stereocenter has two possible configurations, which give rise to stereoisomers (diastereomers and enantiomers) in molecules with one or more stereocenter. For a chiral molecule with one or more stereoc
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https://en.wikipedia.org/wiki/Chirality%20%28physics%29
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A chiral phenomenon is one that is not identical to its mirror image (see the article on mathematical chirality). The spin of a particle may be used to define a handedness, or helicity, for that particle, which, in the case of a massless particle, is the same as chirality. A symmetry transformation between the two is called parity transformation. Invariance under parity transformation by a Dirac fermion is called chiral symmetry.
Chirality and helicity
The helicity of a particle is positive (“right-handed”) if the direction of its spin is the same as the direction of its motion. It is negative (“left-handed”) if the directions of spin and motion are opposite. So a standard clock, with its spin vector defined by the rotation of its hands, has left-handed helicity if tossed with its face directed forwards.
Mathematically, helicity is the sign of the projection of the spin vector onto the momentum vector: “left” is negative, “right” is positive.
The chirality of a particle is more abstract: It is determined by whether the particle transforms in a right- or left-handed representation of the Poincaré group.
For massless particles – photons, gluons, and (hypothetical) gravitons – chirality is the same as helicity; a given massless particle appears to spin in the same direction along its axis of motion regardless of point of view of the observer.
For massive particles – such as electrons, quarks, and neutrinos – chirality and helicity must be distinguished: In the case of thes
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https://en.wikipedia.org/wiki/Paul%20Sabatier%20%28chemist%29
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Prof Paul Sabatier FRS(For) HFRSE (; 5 November 1854 – 14 August 1941) was a French chemist, born in Carcassonne. In 1912, Sabatier was awarded the Nobel Prize in Chemistry along with Victor Grignard. Sabatier was honoured for his work improving the hydrogenation of organic species in the presence of metals.
Education
Sabatier studied at the École Normale Supérieure, starting in 1874. Three years later, he graduated at the top of his class. In 1880, he was awarded a Doctor of Science degree from the College de France.
In 1883 Sabatier succeeded Édouard Filhol at the Faculty of Science, and began a long collaboration with Jean-Baptiste Senderens, so close that it was impossible to distinguish the work of either man.
They jointly published 34 notes in the Accounts of the Academy of Science, 11 memoirs in the Bulletin of the French Chemical Society and 2 joint memoirs to the Annals of Chemistry and Physics.
The methanation reactions of COx were first discovered by Sabatier and Senderens in 1902.
Sabatier and Senderen shared the Academy of Science's Jecker Prize in 1905 for their discovery of the Sabatier–Senderens Process.
After 1905–06 Senderens and Sabatier published few joint works, perhaps due to the classic problem of recognition of the merit of contributions to joint work.
Sabatier taught science classes most of his life before he became Dean of the Faculty of Science at the University of Toulouse in 1905.
Research
Sabatier's earliest research concerned the thermo
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https://en.wikipedia.org/wiki/Stars%20%28M.%20C.%20Escher%29
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Stars is a wood engraving print created by the Dutch artist M. C. Escher in 1948, depicting two chameleons in a polyhedral cage floating through space.
The compound of three octahedra used for the central cage in Stars had been studied before in mathematics, and Escher likely learned of it from the book Vielecke und Vielflache by Max Brückner. Escher used similar compound polyhedral forms in several other works, including Crystal (1947), Study for Stars (1948), Double Planetoid (1949), and Waterfall (1961).
The design for Stars was likely influenced by Escher's own interest in both geometry and astronomy, by a long history of using geometric forms to model the heavens, and by a drawing style used by Leonardo da Vinci. Commentators have interpreted the cage's compound shape as a reference to double and triple stars in astronomy, or to twinned crystals in crystallography. The image contrasts the celestial order of its polyhedral shapes with the more chaotic forms of biology.
Prints of Stars belong to the permanent collections of major museums including the Rijksmuseum, the National Gallery of Art, and the National Gallery of Canada.
Description
Stars is a wood engraving print; that is, it was produced by carving the artwork into the end grain of a block of wood (unlike a woodcut which uses the side grain), and then using this block to print the image. It was created by Escher in October 1948. Although most published copies of Stars are monochromatic, with white artwork aga
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https://en.wikipedia.org/wiki/Quantum%20level
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Quantum level may refer to:
Energy level, a particle that is bound can only take on certain discrete values of energy, called energy levels
Quantum realm, also called the quantum scale, a physics term referring to scales where quantum mechanical effects become important
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https://en.wikipedia.org/wiki/Fisheries%20science
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Fisheries science is the academic discipline of managing and understanding fisheries. It is a multidisciplinary science, which draws on the disciplines of limnology, oceanography, freshwater biology, marine biology, meteorology, conservation, ecology, population dynamics, economics, statistics, decision analysis, management, and many others in an attempt to provide an integrated picture of fisheries. In some cases new disciplines have emerged, as in the case of bioeconomics and fisheries law. Because fisheries science is such an all-encompassing field, fisheries scientists often use methods from a broad array of academic disciplines. Over the most recent several decades, there have been declines in fish stocks (populations) in many regions along with increasing concern about the impact of intensive fishing on marine and freshwater biodiversity.
Fisheries science is typically taught in a university setting, and can be the focus of an undergraduate, master's or Ph.D. program. Some universities offer fully integrated programs in fisheries science. Graduates of university fisheries programs typically find employment as scientists, fisheries managers of both recreational and commercial fisheries, researchers, aquaculturists, educators, environmental consultants and planners, conservation officers, and many others.
Fisheries research
Because fisheries take place in a diverse set of aquatic environments (i.e., high seas, coastal areas, large and small rivers, and lakes of all
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https://en.wikipedia.org/wiki/High-energy%20nuclear%20physics
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High-energy nuclear physics studies the behavior of nuclear matter in energy regimes typical of high-energy physics. The primary focus of this field is the study of heavy-ion collisions, as compared to lighter atoms in other particle accelerators. At sufficient collision energies, these types of collisions are theorized to produce the quark–gluon plasma. In peripheral nuclear collisions at high energies one expects to obtain information on the electromagnetic production of leptons and mesons that are not accessible in electron–positron colliders due to their much smaller luminosities.
Previous high-energy nuclear accelerator experiments have studied heavy-ion collisions using projectile energies of 1 GeV/nucleon at JINR and LBNL-Bevalac up to 158 GeV/nucleon at CERN-SPS. Experiments of this type, called "fixed-target" experiments, primarily accelerate a "bunch" of ions (typically around 106 to 108 ions per bunch) to speeds approaching the speed of light (0.999c) and smash them into a target of similar heavy ions. While all collision systems are interesting, great focus was applied in the late 1990s to symmetric collision systems of gold beams on gold targets at Brookhaven National Laboratory's Alternating Gradient Synchrotron (AGS) and uranium beams on uranium targets at CERN's Super Proton Synchrotron.
High-energy nuclear physics experiments are continued at the Brookhaven National Laboratory's Relativistic Heavy Ion Collider (RHIC) and at the CERN Large Hadron Collider
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https://en.wikipedia.org/wiki/Terry%20Sejnowski
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Terrence Joseph Sejnowski (born 13 August 1947) is the Francis Crick Professor at the Salk Institute for Biological Studies where he directs the Computational Neurobiology Laboratory and is the director of the Crick-Jacobs center for theoretical and computational biology. He has performed pioneering research in neural networks and computational neuroscience.
Sejnowski is also Professor of Biological Sciences and adjunct professor in the departments of neurosciences, psychology, cognitive science, computer science and engineering at the University of California, San Diego, where he is co-director of the Institute for Neural Computation.
With Barbara Oakley, he co-created and taught Learning How To Learn: Powerful mental tools to help you master tough subjects, the world's most popular online course, available on Coursera.
Education and early life
Born in Cleveland in 1947, Sejnowski received his B.S. in physics in 1968 from the Case Western Reserve University, M.A. in physics from Princeton University with John Archibald Wheeler, and a PhD in physics from Princeton University in 1978 with John Hopfield.
While in Princeton for his M.A. in physics, he analyzed the strength of gravitational waves from all known sources at the time, and the required sensitivity needed for detection. He noticed that all gravitational wave detectors were 1000x too insensitive to detect, and, thinking that the requisite detectors would not appear until 30 years later, decided to go into a differ
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https://en.wikipedia.org/wiki/Biol
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Biol may refer to:
Abbreviation for Biology
Biol, a commune of the Isère département, in France
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https://en.wikipedia.org/wiki/Feng%20Kang
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Feng Kang (; September 9, 1920 – August 17, 1993) was a Chinese mathematician. He was elected an academician of the Chinese Academy of Sciences in 1980. After his death, the Chinese Academy of Sciences established the Feng Kang Prize in 1994 to reward young Chinese researchers who made outstanding contributions to computational mathematics.
Early life and education
Feng was born in Nanjing, China and spent his childhood in Suzhou, Jiangsu. He studied at Suzhou High School. In 1939 he was admitted to Department of Electrical Engineering of the National Central University (Nanjing University). Two years later he transferred to the Department of Physics where he studied until his graduation in 1944. He became interested in mathematics and studied it at the university.
Career
After graduation, he contracted spinal tuberculosis and continued to learn mathematics by himself at home. Later in 1946 he went to teach mathematics at Tsinghua University. In 1951 he was appointed as assistant professor at Institute of Mathematics of the Chinese Academy of Sciences. From 1951 to 1953 he worked at Steklov Mathematical Institute in Moscow, under the supervision of Professor Lev Pontryagin. In 1957 he was elected as an associate professor at Institute of Computer Technology of the Chinese Academy of Sciences, where he began his work on computational mathematics and became the founder and leader of computational mathematics and scientific computing in China. In 1978 he was appointed as the f
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https://en.wikipedia.org/wiki/P1
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P1, P01, P-1 or P.1 may refer to:
Computing, robotics, and, telecommunications
DSC-P1, a 2000 Sony Cyber-shot P series camera model
Sony Ericsson P1, a UIQ 3 smartphone
Packet One, the first company to launch WiMAX service in Southeast Asia
Peer 1, an Internet hosting provider
Honda P1, a 1993 Honda P series of robots, an ASIMO predecessor
Media
DR P1, a Danish radio network operated by Danmarks Radio
NRK P1, a Norwegian radio network operated by the Norwegian Broadcasting Corporation
SR P1, a Swedish radio network operated by Sveriges Radio
Polonia 1, a Polish TV channel of the Polcast Television
Military
P-1 Hawk, a 1923 biplane fighter of the U.S. Army Air Corps
Kawasaki P-1, a Japanese maritime patrol aircraft (previously P-X)
P-1 (missile), a Soviet anti-ship cruise missile
Science
Biology
P1 antigen, identifies P antigen system
P1 laboratory, biosafety -level-1 laboratory
P1 phage, a bacterial virus
SARS-CoV-2 Gamma variant, a strain of COVID-19 virus SARS-CoV-2 first detected in Manaus, Brazil in 2020
ATC code P01 Antiprotozoals, a subgroup of the Anatomical Therapeutic Chemical Classification System
Pericarp color1 (p1), a gene in the phlobaphene biosynthesis pathway in maize
C1 and P1 (neuroscience), a component of the visual evoked potential
P1 nuclease, a nuclease that works on single-stranded DNA as well as RNA
Other sciences
Period 1 of the periodic table
Pollard's p − 1 algorithm for integer factorization
P-ONE - a proposed neutri
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https://en.wikipedia.org/wiki/Totalitarian%20principle
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In quantum mechanics, the totalitarian principle states: "Everything not forbidden is compulsory." Physicists including Murray Gell-Mann borrowed this expression, and its satirical reference to totalitarianism, from the popular culture of the early twentieth century.
The statement is in reference to a surprising feature of particle interactions: that any interaction that is not forbidden by a small number of simple conservation laws is not only allowed, but must be included in the sum over all "paths" that contribute to the outcome of the interaction. Hence if it is not forbidden, there is some probability amplitude for it to happen.
In the many-worlds interpretation of quantum mechanics, the principle has a more literal meaning: that every possibility at every interaction that is not forbidden by such a conservation law will actually happen (in some branch of the wave function).
Origin of the phrase
Neither the phrase nor its application to quantum physics originated with Gell-Mann, but a 1956 paper by him contains the first published use of the phrase as a description of quantum physics. Gell-Mann used it to describe the state of particle physics around the time he was formulating the Eightfold Way, a precursor to the quark-model of hadrons.
Formulations close to Gell-Mann's are used in T. H. White's 1958 (not 1938–39) version of The Once and Future King and in Robert Heinlein's 1940 short story "Coventry". They differ in details such as the order of the words "for
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https://en.wikipedia.org/wiki/Bob%20Delaney%20%28politician%29
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Bob Delaney (born ) is a former politician in Ontario, Canada. He was the Liberal member of the Legislative Assembly of Ontario from 2003 to 2018 who represented the ridings of Mississauga West and Mississauga—Streetsville.
Background
Delaney was born in Montreal, Quebec, and has a Bachelor of Science degree in physics from Concordia University in that city. He received a Master of Arts degree in business administration from Simon Fraser University in British Columbia in 1988, and has received accreditation from the Canadian Public Relations Society. He has lived primarily in Mississauga since 1983.
Politics
Delaney ran for the Ontario legislature in the provincial election of 1999 losing to Progressive Conservative cabinet minister John Snobelen by about 9,000 votes in the riding of Mississauga West. After Snobelen resigned from the legislature in early 2003 Delaney ran for the Liberals again in the provincial election of 2003, this time defeating Progressive Conservative candidate Nina Tangri by over 7,000 votes. He was re-elected in 2007, 2011 and 2014.
In 2006, Delaney was appointed the parliamentary assistant (PA) to the Minister Responsible for Seniors. He has subsequently served as PA to the Minister of Research and Innovation, the Minister of Tourism, the Minister of Revenue, the Minister of Education and the Minister of Energy. He also served as chair of the Standing Committee on Finance and Economic Affairs from 2011 to 2013.
On March 25, 2014, he was named Ch
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https://en.wikipedia.org/wiki/Cold%20Spring%20Harbor%20%28disambiguation%29
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Cold Spring Harbor can refer to:
Cold Spring Harbor (album), Billy Joel's first solo album, released in 1971
Cold Spring Harbor (novel), a 1986 novel by Richard Yates
Cold Spring Harbor, New York, a hamlet on Long Island
Cold Spring Harbor (LIRR station), a station on the Long Island Railroad
See also
Cold Spring Harbor Laboratory, a genetics laboratory
Cold Spring Harbor Jr./Sr. High School
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https://en.wikipedia.org/wiki/Open%20reading%20frame
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In molecular biology, open reading frames (ORFs) are defined as spans of DNA sequence between the start and stop codons. Usually, this is considered within a studied region of a prokaryotic DNA sequence, where only one of the six possible reading frames will be "open" (the "reading", however, refers to the RNA produced by transcription of the DNA and its subsequent interaction with the ribosome in translation). Such an ORF may contain a start codon (usually AUG in terms of RNA) and by definition cannot extend beyond a stop codon (usually UAA, UAG or UGA in RNA). That start codon (not necessarily the first) indicates where translation may start. The transcription termination site is located after the ORF, beyond the translation stop codon. If transcription were to cease before the stop codon, an incomplete protein would be made during translation.
In eukaryotic genes with multiple exons, introns are removed and exons are then joined together after transcription to yield the final mRNA for protein translation. In the context of gene finding, the start-stop definition of an ORF therefore only applies to spliced mRNAs, not genomic DNA, since introns may contain stop codons and/or cause shifts between reading frames. An alternative definition says that an ORF is a sequence that has a length divisible by three and is bounded by stop codons. This more general definition can be useful in the context of transcriptomics and metagenomics, where a start or stop codon may not be present
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https://en.wikipedia.org/wiki/Technological%20evolution
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The term "technological evolution" captures explanations of technological change that draw on mechanisms from evolutionary biology. Evolutionary biology has one of its roots in the book “On the origin of species” by Charles Darwin. In the style of this catchphrase, technological evolution might describe the origin of new technologies.
Combinatoric theory of technological change
The combinatoric theory of technological change states that every technology always consists of simpler technologies and a new technology is made of already existing technologies. One notion of this theory is that this interaction of technologies creates a network. All the technologies which interact to form a new technology can be thought of as complements, such as a screwdriver and a screw which by their interaction create the process of screwing a screw. This newly formed process of screwing a screw can be perceived as a technology itself and can therefore be represented by a new node in the network of technologies. The new technology itself can interact with other technologies to form a new technology again. If this process of combining existing technologies is repeated again and again, the network of technologies grows.
The here described mechanism of technological change has been termed “combinatorial evolution”. Others call it “technological recursion”.
Brian Arthur has elaborated how the theory is related to the mechanism of genetic recombination from evolutionary biology and in which aspec
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https://en.wikipedia.org/wiki/Definable
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In mathematical logic, the word definable may refer to:
A definable real number
A definable set
A definable integer sequence
A relation or function definable over a first order structure
A mathematical object or concept that is well-defined
Mathematics disambiguation pages
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https://en.wikipedia.org/wiki/Conference%20on%20Neural%20Information%20Processing%20Systems
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The Conference and Workshop on Neural Information Processing Systems (abbreviated as NeurIPS and formerly NIPS) is a machine learning and computational neuroscience conference held every December. The conference is currently a double-track meeting (single-track until 2015) that includes invited talks as well as oral and poster presentations of refereed papers, followed by parallel-track workshops that up to 2013 were held at ski resorts.
History
The NeurIPS meeting was first proposed in 1986 at the annual invitation-only Snowbird Meeting on Neural Networks for Computing organized by The California Institute of Technology and Bell Laboratories. NeurIPS was designed as a complementary open interdisciplinary meeting for researchers exploring biological and artificial Neural Networks. Reflecting this multidisciplinary approach, NeurIPS began in 1987 with information theorist Ed Posner as the conference president and learning theorist Yaser Abu-Mostafa as program chairman. Research presented in the early NeurIPS meetings included a wide range of topics from efforts to solve purely engineering problems to the use of computer models as a tool for understanding biological nervous systems. Since then, the biological and artificial systems research streams have diverged, and recent NeurIPS proceedings have been dominated by papers on machine learning, artificial intelligence and statistics.
From 1987 until 2000 NeurIPS was held in Denver, United States. Since then, the conferenc
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https://en.wikipedia.org/wiki/Mathematics%20of%20three-phase%20electric%20power
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In electrical engineering, three-phase electric power systems have at least three conductors carrying alternating voltages that are offset in time by one-third of the period. A three-phase system may be arranged in delta (∆) or star (Y) (also denoted as wye in some areas, as symbolically it is similar to the letter 'Y'). A wye system allows the use of two different voltages from all three phases, such as a 230/400 V system which provides 230 V between the neutral (centre hub) and any one of the phases, and 400 V across any two phases. A delta system arrangement provides only one voltage, but it has a greater redundancy as it may continue to operate normally with one of the three supply windings offline, albeit at 57.7% of total capacity. Harmonic current in the neutral may become very large if nonlinear loads are connected.
Definitions
In a star (wye) connected topology, with rotation sequence L1 - L2 - L3, the time-varying instantaneous voltages can be calculated for each phase A,C,B respectively by:
where:
is the peak voltage,
is the phase angle in radians
is the time in seconds
is the frequency in cycles per second and
voltages L1-N, L2-N and L3-N are referenced to the star connection point.
Diagrams
The below images demonstrate how a system of six wires delivering three phases from an alternator may be replaced by just three. A three-phase transformer is also shown.
Balanced loads
Generally, in electric power systems, the loads are distributed as evenl
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https://en.wikipedia.org/wiki/Cupido
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Cupido may refer to:
Biology
Cupido (butterfly), a genus of butterflies
Biotodoma cupido, a species of cichlid
Tympanuchus cupido, the North American greater prairie chicken
Music
Cupido (group), a Spanish band that released the 2019 song "Autoestima"
Cupido (album), a 2023 album by Tini
"Cupido" (Tini song)
"Cupido" (Ivy Queen song), 2012
"Cupido", a 1988 song by El Gran Combo de Puerto Rico from Romántico y Sabroso
Places
Cupido, Suriname, an indigenous village near Wageningen
Cúpido Formation a geologic formation in Mexico
Cupido River, Espírito Santo, Brazil
People
Aidynn Cupido (born 1996), South African rugby union player
Damian Cupido (born 1982), Australian rules footballer
Joey Cupido (born 1990), Canadian lacrosse player
John Cupido (born 1976), South African politician
Keanu Cupido (born 1998), South African footballer
Luca Cupido (born 1995), Italian-born American Olympic water polo player
Paul Cupido (born 1972), Dutch fine art photographer
Other uses
Cupid, or Cupīdō, the Roman god of love
Cupido, a character in the Battle Arena Toshinden fighting game series
763 Cupido, an asteroid
See also
Cupid (disambiguation)
Cupidon (disambiguation)
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https://en.wikipedia.org/wiki/List%20of%20Nobel%20laureates
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The Nobel Prizes (, ) are awarded annually by the Royal Swedish Academy of Sciences, the Swedish Academy, the Karolinska Institutet, and the Norwegian Nobel Committee to individuals and organizations who make outstanding contributions in the fields of chemistry, physics, literature, peace, and physiology or medicine. They were established by the 1895 will of Alfred Nobel, which dictates that the awards should be administered by the Nobel Foundation. An additional prize in memory of Alfred Nobel was established in 1968 by the Sveriges Riksbank (Sweden’s central bank) for outstanding contributions to the field of economics. Each recipient, a Nobelist or laureate, receives a gold medal, a diploma, and a sum of money which is decided annually by the Nobel Foundation.
Prize
Each prize is awarded by a separate committee; the Royal Swedish Academy of Sciences awards the Prizes in Physics, Chemistry, and Economics; the Karolinska Institute awards the Prize in Physiology or Medicine; and the Norwegian Nobel Committee awards the Prize in Peace. Each recipient receives a medal, a diploma and a monetary award that has varied throughout the years. In 1901, the recipients of the first Nobel Prizes were given 150,782 SEK, which is equal to 8,402,670 SEK in December 2017. In 2017, the laureates were awarded a prize amount of 9,000,000 SEK. The awards are presented in Stockholm in an annual ceremony on December 10, the anniversary of Nobel's death.
In years in which the Nobel Prize is not
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https://en.wikipedia.org/wiki/Bryan%20Sykes
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Bryan Clifford Sykes (9 September 1947 – 10 December 2020) was a British geneticist and science writer who was a Fellow of Wolfson College and Emeritus Professor of human genetics at the University of Oxford.
Sykes published the first report on retrieving DNA from ancient bone (Nature, 1989). He was involved in a number of high-profile cases dealing with ancient DNA, including that of Ötzi the Iceman. He also suggested a Florida accountant by the name of Tom Robinson was a direct descendant of Genghis Khan, a claim that was subsequently disproved.
Sykes is best known outside the community of geneticists for his two popular books on the investigation of human history and prehistory through studies of mitochondrial DNA.
Education
Sykes was educated at Eltham College, received his BSc from the University of Liverpool, his PhD from the University of Bristol, and his DSc from the University of Oxford.
Career
The Seven Daughters of Eve
In 2001 (Banta Press Hardback) Sykes published a book for the popular audience, The Seven Daughters of Eve, in which he explained how the dynamics of maternal mitochondrial DNA (mtDNA) inheritance leave their mark on the human population in the form of genetic clans sharing common maternal descent. He notes that the majority of Europeans can be classified in seven such clans, known scientifically as haplogroups, distinguishable by differences in their mtDNA that are unique to each group, with each clan descending from a separate prehistoric
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https://en.wikipedia.org/wiki/Bernard%20Baars
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Bernard J. Baars (born 1946, in Amsterdam) is a former Senior Fellow in Theoretical Neurobiology at The Neurosciences Institute in San Diego, CA., and is currently an Affiliated Fellow there.
He is best known as the originator of the global workspace theory, a theory of human cognitive architecture and consciousness. He previously served as a professor of psychology at the State University of New York, Stony Brook where he conducted research into the causation of human errors and the Freudian slip, and as a faculty member at the Wright Institute.
Baars co-founded the Association for the Scientific Study of Consciousness, and the Academic Press journal Consciousness and Cognition, which he also edited, with William P. Banks, for "more than fifteen years".
In addition to research on global workspace theory with Professor Stan Franklin and others, Baars is working to re-introduce the topic of the conscious brain into the standard college and graduate school curriculum, by writing college textbooks and general audience books, web teaching, advanced seminars and course videos. Baars has also published on animal consciousness, volition, and feelings of knowing, and is currently working on an approach to "higher" states, as defined in the meditation traditions. New brain recording methods continue to reveal unexpected evidence on those topics.
Bibliography
Bernard Baars: The cognitive revolution in psychology, NY: Guilford Press, 1986, .
Bernard Baars: A cognitive theory of
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https://en.wikipedia.org/wiki/John%20Mayow
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John Mayow FRS (1641–1679) was a chemist, physician, and physiologist who is remembered today for conducting early research into respiration and the nature of air. Mayow worked in a field that is sometimes called pneumatic chemistry.
Life
There has been controversy over both the location and year of Mayow's birth, with both Cornwall and London claimed, along with birth years from 1641 to 1645. Proctor's extensive research led him to conclude that Mayow was born in 1641 near Morval in Cornwall and that he was admitted to Wadham College, Oxford at age 17 in 1658. A year later Mayow became a scholar at Oxford, and in 1660 he was elected to a fellowship at All Souls. He graduated in law (bachelor, 1665, doctor, 1670), but made medicine his profession, and became noted for his practice therein, especially in the summer time, in the city of Bath. In 1678, on the proposal of Robert Hooke, Mayow was appointed a fellow of the Royal Society. The following year, after a marriage which was not altogether to Mayow's content, he died in London and was buried in the Church of St Paul, Covent Garden.
Scientific work
Mayow also discovered that there were two constituents of air. Inactive and active. Mayow published at Oxford in 1668 two tracts, on respiration and rickets, and in 1674 these were reprinted, the former in an enlarged and corrected form, with three others De sal-nitro et spiritu nitro-aereo, De respiratione foetus in utero et ovo, and De motu musculari et spiritibus anim
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https://en.wikipedia.org/wiki/Francis%20Guthrie
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Francis Guthrie (born 22 January 1831 in London; d. 19 October 1899 in Claremont, Cape Town) was a South African mathematician and botanist who first posed the Four Colour Problem in 1852. He studied mathematics under Augustus De Morgan, and botany under John Lindley at University College London. Guthrie obtained his B.A. in 1850, and LL.B. in 1852 with first class honours. While colouring a map of the counties of England, he noticed that at least four colours were required so that no two regions sharing a common border were the same colour. He postulated that four colours would be sufficient to colour any map. This became known as the Four Color Problem, and remained one of the most famous unsolved problems in topology for more than a century until it was eventually proven in 1976 using a lengthy computer-aided proof.
Guthrie arrived in South Africa on 10 April 1861 and was met and entertained by Dr Dale (later Sir Langham Dale), who was instrumental in the establishing of the University of the Cape of Good Hope in June 1873. Guthrie took up the post of mathematics master at the Graaff-Reinet College. While there he gave a course of acclaimed public lectures on botany in 1862 and thus started a lifelong friendship with local resident Harry Bolus. He advised Bolus to take up the study of botany to ease his grief at the loss of his six-year-old son. When Bolus left for Cape Town a few years later, he persuaded Guthrie to move there as well in 1875. For a while, he practised
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https://en.wikipedia.org/wiki/Silenes
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In inorganic chemistry, silenes, or disilalkenes, are silicon compounds that contain double bonds. The parent molecule is disilene, .
Structure
The first transient disilene was reported in 1972 by D. N. Roark and Garry J. D. Peddle. Simple disilenes easily polymerize. To suppress this tendency, bulky substituents are used. Indeed the first isolable disilene, tetramesityldisilene, was described in 1981 by West, Fink, and Michl. It was prepared by UV-photolysis of the related cyclic trisilane:
2 [Si(mesityl)2]3 → 3 (mesityl)2Si=Si(mesityl)2
Structure of tetramesityldisilene
Tetramesityldisilene is a yellow-orange solid. The Si=Si double bond lengths of disilenes vary between 2.14 and 2.29 Å and are nearly 5 to 10% shorter than the Si-Si single bond lengths of corresponding disilanes. A peculiarity of disilenes is the trans-bending of the substituents, which is never observed in alkenes. The trans-bent angles of disilenes between the R2Si planes and the Si=Si vector range from 0 to 33.8 °. This distortion is rationalized by the stability of the corresponding silylene fragments, although disilenes do not typically dissociate.
The distorted geometry of disilenes can be rationalized by considering the valence orbitals of silicon, which are 3s and 3p, whereas those of carbon are 2s and 2p. Thus, the energy gap between the ns and np orbitals of a silicon atom is larger than that of a carbon atom.
Therefore, silylene fragments are in a singlet state, while carbene fragments ar
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https://en.wikipedia.org/wiki/MacDiarmid%20Institute%20for%20Advanced%20Materials%20and%20Nanotechnology
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The MacDiarmid Institute for Advanced Materials and Nanotechnology (often simply called the MacDiarmid Institute) is a New Zealand Centre of Research Excellence (CoRE) specialising in materials science and nanotechnology. It is hosted by Victoria University of Wellington, and is a collaboration between five universities and two Crown Research Institutes.
Background
The Institute is named after Alan MacDiarmid, a New Zealander who won the Nobel Prize in Chemistry in 2000. It is funded by the New Zealand government through the Tertiary Education Commission.
The Institute divides its work into four research areas:
Towards Zero Waste - Reconfigurable Systems
Towards Zero Carbon - Catalytic Architectures
Towards Low Energy Tech - Hardware for Future Computing
Sustainable resource use - Mātauranga Māori Research Programme
Awards
From 2004 to 2007, the MacDiarmid Institute sponsored the annual Young Scientist of the Year awards for up-and-coming scientists and researchers in New Zealand, organised by the Foundation for Research, Science and Technology. These awards replaced the FiRST Scholarship Awards, and have subsequently been replaced by the Prime Minister's MacDiarmid Emerging Scientist Prize.
Directors
See also
Cather Simpson
Alison Downard
References
External links
MacDiarmid Institute website
MacDiarmid Institute's BioNanotechnology network
Research institutes in New Zealand
Victoria University of Wellington
Nanotechnology institutions
2002 establishments in New
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https://en.wikipedia.org/wiki/Wu%20Youxun
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Wu Youxun (; 26 April 1897 – 30 November 1977), also known as Y. H. Woo, was a Chinese physicist. His courtesy name was Zhèngzhī ().
Biography
Wu graduated from the Department of Physics of Nanjing Higher Normal School (later renamed National Central University and Nanjing University), and was later associated with the Department of Physics at Tsinghua University. He served as president of National Central University and Jiaotong University in Shanghai. When he was a graduate student at the University of Chicago he studied x-ray and electron scattering, and verified the Compton effect which gave Arthur Compton the Nobel Prize in Physics.
Awards
In 2000, the Chinese Physical Society established five prizes, in recognition of five pioneers of modern physics in China. The Wu Youxun Prize is awarded to physicists in nuclear physics.
References
1897 births
1977 deaths
Boxer Indemnity Scholarship recipients
Educators from Jiangxi
Members of Academia Sinica
Members of the Chinese Academy of Sciences
Nanjing University alumni
National Central University alumni
Academic staff of the National Southwestern Associated University
People from Yichun, Jiangxi
Physicists from Jiangxi
Presidents of National Central University
Presidents of Nanjing University
Presidents of Shanghai Jiao Tong University
Academic staff of Shanghai Jiao Tong University
Academic staff of Tsinghua University
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https://en.wikipedia.org/wiki/Classical%20mathematics
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In the foundations of mathematics, classical mathematics refers generally to the mainstream approach to mathematics, which is based on classical logic and ZFC set theory. It stands in contrast to other types of mathematics such as constructive mathematics or predicative mathematics. In practice, the most common non-classical systems are used in constructive mathematics.
Classical mathematics is sometimes attacked on philosophical grounds, due to constructivist and other objections to the logic, set theory, etc., chosen as its foundations, such as have been expressed by L. E. J. Brouwer. Almost all mathematics, however, is done in the classical tradition, or in ways compatible with it.
Defenders of classical mathematics, such as David Hilbert, have argued that it is easier to work in, and is most fruitful; although they acknowledge non-classical mathematics has at times led to fruitful results that classical mathematics could not (or could not so easily) attain, they argue that on the whole, it is the other way round.
See also
Constructivism (mathematics)
Finitism
Intuitionism
Non-classical analysis
Traditional mathematics
Ultrafinitism
Philosophy of Mathematics
References
Mathematical logic
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https://en.wikipedia.org/wiki/Large%20eddy%20simulation
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Large eddy simulation (LES) is a mathematical model for turbulence used in computational fluid dynamics. It was initially proposed in 1963 by Joseph Smagorinsky to simulate atmospheric air currents, and first explored by Deardorff (1970). LES is currently applied in a wide variety of engineering applications, including combustion, acoustics, and simulations of the atmospheric boundary layer.
The simulation of turbulent flows by numerically solving the Navier–Stokes equations requires resolving a very wide range of time and length scales, all of which affect the flow field. Such a resolution can be achieved with direct numerical simulation (DNS), but DNS is computationally expensive, and its cost prohibits simulation of practical engineering systems with complex geometry or flow configurations, such as turbulent jets, pumps, vehicles, and landing gear.
The principal idea behind LES is to reduce the computational cost by ignoring the smallest length scales, which are the most computationally expensive to resolve, via low-pass filtering of the Navier–Stokes equations. Such a low-pass filtering, which can be viewed as a time- and spatial-averaging, effectively removes small-scale information from the numerical solution. This information is not irrelevant, however, and its effect on the flow field must be modelled, a task which is an active area of research for problems in which small-scales can play an important role, such as near-wall flows, reacting flows, and multiphase
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https://en.wikipedia.org/wiki/Alan%20MacDiarmid
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Alan Graham MacDiarmid, ONZ FRS (14 April 1927 – 7 February 2007) was a New Zealand-born American chemist, and one of three recipients of the Nobel Prize for Chemistry in 2000.
Early life and education
MacDiarmid was born in Masterton, New Zealand as one of five children – three brothers and two sisters. His family was relatively poor, and the Great Depression made life difficult in Masterton, due to which his family shifted to Lower Hutt, a few miles from Wellington, New Zealand. At around age ten, he developed an interest in chemistry from one of his father's old textbooks, and he taught himself from this book and from library books.
MacDiarmid was educated at Hutt Valley High School and Victoria University of Wellington.
In 1943, MacDiarmid passed the University of New Zealand's University Entrance Exam and its Medical Preliminary Exam. He then took up a part-time job as a "lab boy" or janitor at Victoria University of Wellington during his studies for a BSc degree, which he completed in 1947. He was then appointed demonstrator in the undergraduate laboratories. After completing an MSc in chemistry from the same university, he worked as an assistant in its chemistry department. It was here that he had his first publication in 1949, in the scientific journal Nature. He graduated in 1951 with first class honours, and won a Fulbright Fellowship to the University of Wisconsin–Madison. He majored in inorganic chemistry, receiving his M.S. degree in 1952 and his PhD in 1953.
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https://en.wikipedia.org/wiki/Thigmotropism
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In plant biology, thigmotropism is a directional growth movement which occurs as a mechanosensory response to a touch stimulus. Thigmotropism is typically found in twining plants and tendrils, however plant biologists have also found thigmotropic responses in flowering plants and fungi. This behavior occurs due to unilateral growth inhibition. That is, the growth rate on the side of the stem which is being touched is slower than on the side opposite the touch. The resultant growth pattern is to attach and sometimes curl around the object which is touching the plant. However, flowering plants have also been observed to move or grow their sex organs toward a pollinator that lands on the flower, as in Portulaca grandiflora.
Physiological factors
Since growth is a complex developmental procedure, there are indeed many requirements (both biotic and abiotic) that are needed for both touch perception and a thigmotropic response to occur. One of these is calcium. In a series of experiments in 1995 using the tendril Bryonia dioica, touch-sensing calcium channels were blocked using various antagonists. Responses to touch in treatment plants which received calcium channel inhibitors were diminished compared to control plants, indicating that calcium may be required for thigmotropism. Later in 2001, a membrane depolarization pathway was proposed in which calcium was involved: when a touch occurs, calcium channels open and calcium flows into the cell, shifting the electrochemical potent
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https://en.wikipedia.org/wiki/Georgia%204-H
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Georgia 4-H was founded in 1904 by G.C. Adams in Newton County, Georgia, United States, as the Girls Canning, and Boys Corn Clubs.
The Georgia 4-H Program is a branch of Georgia Cooperative Extension, which is part of the University of Georgia College of Agriculture and Environmental Sciences, and is funded by the University System of Georgia and private partners.
History
Georgia 4-H began with the start of the special Boys Corn Club contest that was first organized by Superintendent of Schools, G. C. Adams. Like the corn club he organized 100 years ago, G. C. Adams was unique. He ranked high as an educator. He taught at Pine Grove School in Newton County, he was principal of Palmer Institute at Oxford, he served as county school commissioner, and he was the president of the Fifth District Agriculture School at Monroe. Yet, Mr. Adams never attended high school or college, and he did not go to school more than a year in his entire life. While writing about Mr. Adams in the Atlanta Constitution after he had been elected Georgia commissioner of agriculture in 1932, Stiles A. Martin called him "one of the best educated, best read and most learned men in the state."
Perhaps Mr. Adams' greatest accomplishment was organizing the corn club, and he is best known for that; but he was a pioneer in other fields, too. He also single-handedly developed a plan for transporting school children, which probably resulted in our school buses of today. In the same year he organized an oratori
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https://en.wikipedia.org/wiki/Paul%20Flory
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Paul John Flory (June 19, 1910 – September 9, 1985) was an American chemist and Nobel laureate who was known for his work in the field of polymers, or macromolecules. He was a leading pioneer in understanding the behavior of polymers in solution, and won the Nobel Prize in Chemistry in 1974 "for his fundamental achievements, both theoretical and experimental, in the physical chemistry of macromolecules".
Biography
Personal life
Flory was born in Sterling, Illinois, on June 19, 1910. He was raised by Ezra Flory and Nee Martha Brumbaugh. His father worked as a clergyman-educator, and his mother was a school teacher. He first gained his interest in science from Carl W Holl, who was a professor in chemistry. Holl was employed in Indiana at Manchester College as a chemistry professor. In 1936, he married Emily Catherine Tabor. He and Emily had three children together: Susan Springer, Melinda Groom and Paul John Flory, Jr. They also had five grandchildren. All of his children pursued careers in the field of science. His first position was at DuPont with Wallace Carothers. He was posthumously inducted into the Alpha Chi Sigma Hall of Fame in 2002. Flory died on September 9, 1985, due to a massive heart attack. His wife Emily died in 2006 aged 94.
Schooling
After graduating from Elgin High School in Elgin, Illinois in 1927, Flory received a bachelor's degree from Manchester College (Indiana) (now Manchester University) in 1931 and a Ph.D. from the Ohio State University in 1934
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https://en.wikipedia.org/wiki/JCM
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JCM may refer to:
Japan Collection of Microorganisms
James Clerk Maxwell
John Cougar Mellencamp
Journal of Clinical Microbiology
Journal of Communications
AGM-169 Joint Common Missile
Jewish Children's Museum
Jackson Central-Merry High School, a public high school in Jackson, Tennessee
JunoCam, a camera on a planned space probe to the planet Jupiter
Joint Council of Municipalities
Jaynes-Cummings model
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https://en.wikipedia.org/wiki/Overdominance
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Overdominance is a rare condition in genetics where the phenotype of the heterozygote lies outside the phenotypical range of both homozygous parents. Overdominance can also be described as heterozygote advantage regulated by a single genomic locus, wherein heterozygous individuals have a higher fitness than homozygous individuals. However, not all cases of the heterozygote advantage are considered overdominance, as they may be regulated by multiple genomic regions. Overdominance has been hypothesized as an underlying cause for heterosis (increased fitness of hybrid offspring).
Examples
Sickle cell anemia
An example of overdominance in humans is that of the sickle cell anemia. This condition is determined by a single polymorphism. Possessors of the deleterious allele have lower life expectancy, with homozygotes rarely reaching 50 years of age. However, this allele also yields some resistance to malaria. Thus in regions where malaria exerts or has exerted a strong selective pressure, sickle cell anemia has been selected for its conferred partial resistance to the disease. While homozygotes will have either no protection from malaria or a dramatic propensity to sickle cell anemia, heterozygotes have fewer physiological effects and a partial resistance to malaria.
Salmonoid major histocompatibility complex
Major histocompatibility complex (MHC) genes exhibit extensive variation, generally attributed to the notion of heterozygous individuals identifying a wider range of pepti
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https://en.wikipedia.org/wiki/Change%20of%20basis
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In mathematics, an ordered basis of a vector space of finite dimension allows representing uniquely any element of the vector space by a coordinate vector, which is a sequence of scalars called coordinates. If two different bases are considered, the coordinate vector that represents a vector on one basis is, in general, different from the coordinate vector that represents on the other basis. A change of basis consists of converting every assertion expressed in terms of coordinates relative to one basis into an assertion expressed in terms of coordinates relative to the other basis.
Such a conversion results from the change-of-basis formula which expresses the coordinates relative to one basis in terms of coordinates relative to the other basis. Using matrices, this formula can be written
where "old" and "new" refer respectively to the firstly defined basis and the other basis, and are the column vectors of the coordinates of the same vector on the two bases, and is the change-of-basis matrix (also called transition matrix), which is the matrix whose columns are the coordinate vectors of the new basis vectors on the old basis.
This article deals mainly with finite-dimensional vector spaces. However, many of the principles are also valid for infinite-dimensional vector spaces.
Change of basis formula
Let be a basis of a finite-dimensional vector space over a field .
For , one can define a vector by its coordinates over
Let
be the matrix whose th column is fo
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https://en.wikipedia.org/wiki/Kenneth%20Campbell%20%28VC%29
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Kenneth Campbell, (21 April 1917 – 6 April 1941) was a British airman who was posthumously awarded the Victoria Cross for an attack that damaged the German battlecruiser Gneisenau, moored in Brest, France, during the Second World War.
Early life
Kenneth Campbell was from Ayrshire and educated at Sedbergh School. He gained a chemistry degree at Clare College, Cambridge, where he was a member of the Cambridge University Air Squadron.
Second World War
In September 1939, Campbell was mobilised for service with the Royal Air Force (RAF) following the outbreak of the Second World War. Flying Officer Campbell joined No. 22 Squadron RAF in September 1940, piloting the Bristol Beaufort torpedo bomber. Campbell torpedoed a merchant vessel near Borkum in March 1941. Days later, he escaped from a pair of Messerschmitt Bf 110 fighters, despite extensive damage to his aircraft. Two days later, on a 'Rover' patrol he torpedoed another vessel, off IJmuiden.
On 6 April 1941 over Brest Harbour, France, Flying Officer Campbell attacked the German battleship Gneisenau. He flew his Beaufort through the gauntlet of concentrated anti-aircraft fire from about 1000 weapons of all calibres and launched a torpedo at a height of .
The attack had to be made with absolute precision: the Gneisenau was moored only some away from a mole in Brest's inner harbour. For the attack to be effective, Campbell would have to time the release to drop the torpedo close to the side of the mole. That Campbell manag
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https://en.wikipedia.org/wiki/Alfred%20Werner
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Alfred Werner (12 December 1866 – 15 November 1919) was a Swiss chemist who was a student at ETH Zurich and a professor at the University of Zurich. He won the Nobel Prize in Chemistry in 1913 for proposing the octahedral configuration of transition metal complexes. Werner developed the basis for modern coordination chemistry. He was the first inorganic chemist to win the Nobel Prize, and the only one prior to 1973.
Biography
Werner was born in 1866 in Mulhouse, Alsace (which was then part of France, but which was annexed by Germany in 1871). He was raised as Roman Catholic. He was the fourth and last child of Jean-Adam Werner, a foundry worker, and his second wife, Salomé Jeanette Werner, who originated from a wealthy family. He went to Switzerland to study chemistry at the Swiss Federal Institute (polytechnikum) in Zurich. Still, since this institute was not empowered to grant doctorates until 1909, Werner received a doctorate formally from the University of Zürich in 1890. After postdoctoral study in Paris, he returned to the Swiss Federal Institute to teach (1892). In 1893 he moved to the University of Zurich, where he became a professor in 1895. In 1894 he became a Swiss citizen.
In his last year, he suffered from a general, progressive, degenerative arteriosclerosis, especially of the brain, aggravated by years of excessive drinking and overwork. He died in a psychiatric hospital in Zurich.
Werner died on 15 November 1919 of arteriosclerosis in Zürich at the age of 5
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https://en.wikipedia.org/wiki/Dendroid
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The word Dendroid derives from the Greek word "dendron" meaning ( "tree-like")
Dendroid may refer to:
Dendroid (topology), in mathematics
Dendroid (malware), Android malware
See also
Dendrite (disambiguation)
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https://en.wikipedia.org/wiki/Neutralism
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Neutralism may refer to:
Biology
Neutral theory of molecular evolution
Politics
Neutral country
Nonalignment (disambiguation)
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https://en.wikipedia.org/wiki/Pieter%20Kok
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Pieter Kok (born in June 1972) is a Dutch physicist and one of the co-developers of quantum interferometric optical lithography.
Kok was born in Friesland in the Netherlands. In 1997 he graduated from the University of Utrecht with a degree in Foundations of Quantum Theory. In 2001, he received his PhD in physics from the University of Wales, Bangor. His research specializations include linear optical implementations of quantum communication and computation protocols, quantum teleportation and the interpretation of quantum theory.
Dr. Kok has worked in the Quantum Computing Technologies Group at the NASA/Jet Propulsion Laboratory, in Pasadena, California, Hewlett-Packard Laboratories in Bristol, England and at the Department of Materials, University of Oxford. He is a Professor of Theoretical Physics at the University of Sheffield.
He and his wife, Rose Roberto, live in northern England with their two children.
References
Selected publications
External links
"Quantum Computing" in
https://web.archive.org/web/20120209122709/http://ldsd.group.shef.ac.uk/members/?name=Kok
thesis url summary
1972 births
Living people
21st-century Dutch physicists
Alumni of Bangor University
People from Friesland
Theoretical physicists
Utrecht University alumni
Academics of the University of Sheffield
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https://en.wikipedia.org/wiki/ESN
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ESN may refer to:
Eastern Security Network, the armed wing of the Indigenous People of Biafra (IPOB)
Easton Airport (Maryland), United States
Echo state network in computer science
Edmonton Street News, a Canadian newspaper
Einstein summation notation, used in mathematical physics
Electronic serial number for mobile devices
Emergency Services Network, in the UK
Entertainment Studios Networks, an American cable network
Erasmus Student Network, a European student organization
European Sensory Network, studies the five senses
European Society for Neurochemistry
Salvadoran Sign Language
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https://en.wikipedia.org/wiki/Ancient%20Egyptian%20mathematics
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Ancient Egyptian mathematics is the mathematics that was developed and used in Ancient Egypt 3000 to c. , from the Old Kingdom of Egypt until roughly the beginning of Hellenistic Egypt. The ancient Egyptians utilized a numeral system for counting and solving written mathematical problems, often involving multiplication and fractions. Evidence for Egyptian mathematics is limited to a scarce amount of surviving sources written on papyrus. From these texts it is known that ancient Egyptians understood concepts of geometry, such as determining the surface area and volume of three-dimensional shapes useful for architectural engineering, and algebra, such as the false position method and quadratic equations.
Overview
Written evidence of the use of mathematics dates back to at least 3200 BC with the ivory labels found in Tomb U-j at Abydos. These labels appear to have been used as tags for grave goods and some are inscribed with numbers. Further evidence of the use of the base 10 number system can be found on the Narmer Macehead which depicts offerings of 400,000 oxen, 1,422,000 goats and 120,000 prisoners. Archaeological evidence has suggested that the Ancient Egyptian counting system had origins in Sub-Saharan Africa. Also, fractal geometry designs which are widespread among Sub-Saharan African cultures are also found in Egyptian architecture and cosmological signs.
The evidence of the use of mathematics in the Old Kingdom (c. 2690–2180 BC) is scarce, but can be deduced from
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https://en.wikipedia.org/wiki/Overlapping%20subproblems
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In computer science, a problem is said to have overlapping subproblems if the problem can be broken down into subproblems which are reused several times or a recursive algorithm for the problem solves the same subproblem over and over rather than always generating new subproblems.
For example, the problem of computing the Fibonacci sequence exhibits overlapping subproblems. The problem of computing the nth Fibonacci number F(n), can be broken down into the subproblems of computing F(n − 1) and F(n − 2), and then adding the two. The subproblem of computing F(n − 1) can itself be broken down into a subproblem that involves computing F(n − 2). Therefore, the computation of F(n − 2) is reused, and the Fibonacci sequence thus exhibits overlapping subproblems.
A naive recursive approach to such a problem generally fails due to an exponential complexity. If the problem also shares an optimal substructure property, dynamic programming is a good way to work it out.
Fibonacci sequence example in C
Consider the following C code:
#include <stdio.h>
#define N 5
static int fibMem[N];
int fibonacci(int n) {
int r = 1;
if (n > 2) {
r = fibonacci(n - 1) + fibonacci(n - 2);
}
fibMem[n - 1] = r;
return r;
}
void printFibonacci() {
int i;
for (i = 1; i <= N; i++) {
printf("fibonacci(%d): %d\n", i, fibMem[i - 1]);
}
}
int main(void) {
fibonacci(N);
printFibonacci();
return 0;
}
/* Output:
fibonacci(1): 1
fibonacci(2): 1
fibonacci(3): 2
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