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Semiconductor device

A semiconductor device is an electronic component that relies on the electronic properties of a semiconductor material for its function. Semiconductor devices have replaced vacuum tubes in most applications, they use electrical conduction in the solid state rather than the gaseous state or thermionic emission in a vacuum. Semiconductor devices are manufactured both as single discrete devices and as integrated circuit chips, which consist of two or more devices—which can number from the hundreds to the billions—manufactured and interconnected on a single semiconductor wafer. Semiconductor materials are useful because their behavior can be manipulated by the deliberate addition of impurities, known as doping. Semiconductor conductivity can be controlled by the introduction of an electric or magnetic field, by exposure to light or heat, or by the mechanical deformation of a doped monocrystalline silicon grid. Current conduction in a semiconductor occurs due to mobile or "free" electrons and electron holes, collectively known as charge carriers.

Doping a semiconductor with a small proportion of an atomic impurity, such as phosphorus or boron increases the number of free electrons or holes within the semiconductor. When a doped semiconductor contains excess holes, it is called a p-type semiconductor. A majority of mobile charge carriers have negative charge; the manufacture of semiconductors controls the location and concentration of p- and n-type dopants. The connection of n-type and p-type semiconductors form p–n junctions; the most common semiconductor device in the world is the MOSFET called the MOS transistor. As of 2013, billions of MOS transistors are manufactured every day. Semiconductor devices made per year have been growing by 9.1% on average since 1978, shipments in 2018 are predicted for the first time to exceed 1 trillion, meaning that well over 7 trillion has been made to date, in just in the decade prior. A semiconductor diode is a device made from a single p–n junction. At the junction of a p-type and an n-type semiconductor there forms a depletion region where current conduction is inhibited by the lack of mobile charge carriers.

When the device is forward biased, this depletion region is diminished, allowing for significant conduction, while only small current can be achieved when the diode is reverse biased and thus the depletion region expanded. Exposing a semiconductor to light can generate electron–hole pairs, which increases the number of free carriers and thereby the conductivity. Diodes optimized to take advantage of this phenomenon are known as photodiodes. Compound semiconductor diodes can be used to generate light, as in light-emitting diodes and laser diodes. Bipolar junction transistors are formed from two p–n junctions, in either n–p–n or p–n–p configuration; the middle, or base, region between the junctions is very narrow. The other regions, their associated terminals, are known as the emitter and the collector. A small current injected through the junction between the base and the emitter changes the properties of the base-collector junction so that it can conduct current though it is reverse biased; this creates a much larger current between the collector and emitter, controlled by the base-emitter current.

Another type of transistor, the field-effect transistor, operates on the principle that semiconductor conductivity can be increased or decreased by the presence of an electric field. An electric field can increase the number of free electrons and holes in a semiconductor, thereby changing its conductivity; the field may be applied by a reverse-biased p–n junction, forming a junction field-effect transistor or by an electrode insulated from the bulk material by an oxide layer, forming a metal–oxide–semiconductor field-effect transistor. The metal-oxide-semiconductor FET, a solid-state device, is by far the most used semiconductor device today, it accounts for at least 99.9% of all transistors, there have been an estimated 13 sextillion MOSFETs manufactured between 1960 and 2018. The gate electrode is charged to produce an electric field that controls the conductivity of a "channel" between two terminals, called the source and drain. Depending on the type of carrier in the channel, the device may be an n-channel or a p-channel MOSFET.

Although the MOSFET is named in part for its "metal" gate, in modern devices polysilicon is used instead. By far, silicon is the most used material in semiconductor devices, its combination of low raw material cost simple processing, a useful temperature range makes it the best compromise among the various competing materials. Silicon used in semiconductor device manufacturing is fabricated into boules that are large enough in diameter to allow the production of 300 mm wafers. Germanium was a used early semiconductor material but its thermal sensitivity makes it less useful than silicon. Today, germanium is alloyed with silicon for use in very-high-speed SiGe devices. Gallium arsenide is widely used in high-speed devices but so far, it has been difficult to form large-diameter boules of this material, limiting the wafer diameter to sizes smaller than silicon wafers thus making m

John Rupert Firth

John Rupert Firth known as J. R. Firth, was an English linguist and a leading figure in British linguistics during the 1950s, he was Professor of English at the University of the Punjab from 1919–1928. He worked in the phonetics department of University College London before moving to the School of Oriental and African Studies, where he became Professor of General Linguistics, a position he held until his retirement in 1956, his work on prosody, which he emphasised at the expense of the phonemic principle, prefigured work in autosegmental phonology. Firth is noted for drawing attention to the context-dependent nature of meaning with his notion of'context of situation', his work on collocational meaning is acknowledged in the field of distributional semantics. In particular, he is known for the famous quotation: You shall know a word by the company it keeps Firth developed a particular view of linguistics that has given rise to the adjective'Firthian'. Central to this view is the idea of polysystematism.

David Crystal describes this as: an approach to linguistic analysis based on the view that language patterns cannot be accounted for in terms of a single system of analytic principles and categories... but that different systems may need to be set up at different places within a given level of description. His approach can be considered as resuming that of Malinowski's anthropological semantics, as a precursor of the approach of semiotic anthropology. Anthropological approaches to semantics are alternative to the three major types of semantics approaches: linguistic semantics, logical semantics, General semantics. Other independent approaches to semantics are psychological semantics; as a teacher in the University of London for more than 20 years, Firth influenced a generation of British linguists. The popularity of his ideas among contemporaries gave rise to what was known as the'London School' of linguistics. Among Firth's students, the so-called neo-Firthians were exemplified by Michael Halliday, Professor of General Linguistics in the University of London from 1965 until 1971.

Firth encouraged a number of his students, who became well known linguists, to carry out research on a number of African and Oriental languages. T. F. Mitchell worked on Arabic and Berber, Frank R. Palmer on Ethiopian languages, including Tigre, Michael Halliday on Chinese; some other students whose native tongues were not English worked with him and that enriched Firth's theory on prosodic analysis. Among his influential students were the Arab linguists Ibrahim Anis, Tammam Hassan and Kamal Bashir. Firth got many insights from work done by his students in Semitic and Oriental languages so he made a great departure from the linear analysis of phonology and morphology to a more of syntagmatic and paradigmatic analysis, where it is important to distinguish between the two levels of phonematic units and prosodies. Prosodic analysis paved the way to autosegmental phonology, though many linguists, who do not have a good background on the history of phonology, do not acknowledge this. Speech London: Benn's Sixpenny Library.

The Tongues of Men London: Watts & Co. Papers in Linguistics 1934–1951 London: Oxford University Press. A synopsis of linguistic theory 1930-1955, in Firth, Studies in Linguistic Analysis, Special volume of the Philological Society, chapter 1, pages 1-32, Oxford: Blackwell. Phonaestheme Systemic linguistics Chapman, S. & Routledge, P. Key Thinkers in Linguistics and the Philosophy of Language. Edinburgh: Edinburgh University Press. Pp 80-86

2008 Asian Men's Volleyball Cup

The 2008 Asian Men's Volleyball Cup was the 1st edition of the AVC Cup for Men, played by top eight teams of the 2007 Asian Championship. It was held at MCC Hall Convention Center, Nakhon Ratchasima, Thailand from 20 to 26 September 2008; the teams are seeded based on their final ranking at the 2007 Asian Men's Volleyball Championship. MCC Hall Convention Center, Nakhon Ratchasima, Thailand MVP: Hamzeh Zarini Best Scorer: Yasuyuki Shibakoya Best Spiker: Park Chul-woo Best Server: Cui Jianjun Best Setter: Saranchit Charoensuk Best Receiver: Yeo Oh-hyun Best Digger: Chien Wei-lun Best Libero: Yeo Oh-hyun Asian Volleyball Confederation

Scolytoplatypus

Scolytoplatypus is a genus of beetles belonging to the family Curculionidae. The genus contains about 47 to 50 species worldwide. In Asia, 29 species known, 11 or 12 are known in 7 species in Madagascar. Males and females are dimorphic. Male frons distinctly concave as opposed to the convex female frons. Asian species can be separated from African counterparts by having sexually dimorphic antennae. Scolytoplatypus acuminatus Scolytoplatypus africanus Scolytoplatypus armatus Scolytoplatypus blandfordi Scolytoplatypus brahma Scolytoplatypus calvus Scolytoplatypus cirratus Scolytoplatypus congonus Scolytoplatypus curviciliosus Scolytoplatypus eichelbaumi Scolytoplatypus exiguus Scolytoplatypus daimio Scolytoplatypus darjeelingi Scolytoplatypus fasciatus Scolytoplatypus gardneri Scolytoplatypus hova Scolytoplatypus kivuensis Scolytoplatypus kunala Scolytoplatypus lopchuensis Scolytoplatypus luzonicus Scolytoplatypus macgregori Scolytoplatypus mikado Scolytoplatypus minimus Scolytoplatypus mutabilis Scolytoplatypus neglectus Scolytoplatypus nitidicollis Scolytoplatypus obtectus Scolytoplatypus occidentalis Scolytoplatypus opacicollis Scolytoplatypus permirus Scolytoplatypus pubescens Scolytoplatypus raja Scolytoplatypus ruficauda Scolytoplatypus rugosus Scolytoplatypus samsinghensis Scolytoplatypus shogun Scolytoplatypus supercilliosus Scolytoplatypus truncatus Scolytoplatypus unipilus Scolytoplatypus uter Scolytoplatypus zahradniki

Bar/None Records

Bar/None Records is an independent record label based in Hoboken, New Jersey. Tom Prendergast started Bar/None in early 1986 in New Jersey. Having worked in pirate radio and booked and promoted bands in his native Ireland, Prendergast moved to Hoboken in 1982; the first release on Bar/None was by Rage to Live, whose leader, Glenn Morrow, soon became a partner in the label. Morrow had built a network of contacts in the alternative music community having toured nationally with his previous band, The Individuals, had worked in the A&R department of Warner Bros. and as the managing editor of New York Rocker magazine. In 2000, Prendergast moved back to Ireland, sold his shares to Morrow; the Bar/None debut album of They Might Be Giants sold more than 100,000 copies and their follow-up, more than doubled those sales. Other artists that started on Bar/None and went on to the major record labels include Luka Bloom, Yo La Tengo, Freedy Johnston and Tindersticks. List of record labels Official site

1952–53 Netherlands Football League Championship

The Netherlands Football League Championship 1952–1953 was contested by 56 teams participating in four divisions. The national champion would be determined by a play-off featuring the winners of each division of the Netherlands. RCH won this year's championship by beating Sparta Rotterdam and Vitesse Arnhem. Eerste Klasse A: Moving in from other divisions: AFC Ajax, DOS, NEC Nijmegen, RCH, Sneek Wit Zwart, VSV, FC Wageningen and Zwolsche Boys Promoted from 2nd Division: HeraclesEerste Klasse B: Moving in from other divisions: AGOVV Apeldoorn, DWS, Elinkwijk, Go Ahead, HVV't Gooi, HFC Haarlem and sc Heerenveen Promoted from 2nd Division: StormvogelsEerste Klasse C: Moving in from other divisions: Brabantia, Emma, HBS Craeyenhout, LONGA, Sparta Rotterdam, Theole and VVV Venlo Promoted from 2nd Division: SBV ExcelsiorEerste Klasse D: Moving in from other divisions: ADO Den Haag, Bleijerheide, DHC Delft, FC Eindhoven, Feijenoord, NAC and RBC Roosendaal Promoted from 2nd Division: TEC Tiel RSSSF Netherlands Football League Championships 1898-1954