C 20
C++20 is a version of the ISO/IEC 14882 standard for the C++ programming language. C++20 replaced the prior version of the C++ standard, called C++17. The standard was technically finalized by WG21 at the meeting in Prague in February 2020, approved on 4 September 2020, and published in December 2020. Features C++20 adds more new major features than C++14 or C++17. Changes that have been accepted into C++20 include: Language * concepts, with terse syntax * modules * designated initializers (based on the C99 feature, and common g++ extension) * , this/code> as a lambda capture * template parameter lists on lambdas * three-way comparison using the "spaceship operator", operator <=> * initialization of an additional variable within a range-based for statement * lambdas in unevaluated contexts * default constructible and assignable stateless lambdas * allow pack expansions in lambda ''init-capture'' * class types in non-type template parameters, also allowing string ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Carbon-20
Carbon (6C) has 15 known isotopes, from to , of which and are stable. The longest-lived radioisotope is , with a half-life of years. This is also the only carbon radioisotope found in nature—trace quantities are formed cosmogenically by the reaction + → + . The most stable artificial radioisotope is , which has a half-life of . All other radioisotopes have half-lives under 20 seconds, most less than 200 milliseconds. The least stable isotope is , with a half-life of . List of isotopes , - , , style="text-align:right" , 6 , style="text-align:right" , 2 , , [] , proton emission, 2p , Subsequently decays by double proton emission to for a net reaction of → + 4 , 0+ , , , - , rowspan=3, , rowspan=3 style="text-align:right" , 6 , rowspan=3 style="text-align:right" , 3 , rowspan=3, , rowspan=3, , β+ () , , rowspan=3, 3/2− , rowspan=3, , rowspan=3, , - , β+α () , Immediately decays by proton emission to for a net reaction of → ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Fokker F-32
The Fokker F-32 was a passenger aircraft built by the Fokker Aircraft Corporation of America in 1929 in their Teterboro, New Jersey factory. It was the first four-engined aircraft designed and built in the United States. Ten examples were built, but they only entered limited commercial service; their high cost and problems with the cooling of the aft engines proved prohibitive. The United States Army Air Corps evaluated the F-32 as the YC-20, but did not purchase it. Crash The first F-32 crashed on November 27, 1929, during a demonstration of a three-engined takeoff from Roosevelt Field (airport), Roosevelt Field on Long Island, New York. One of the two port engines was stopped, but the other failed shortly after takeoff, causing a loss of control. The aircraft came down on a house in nearby Carle Place, New York, Carle Place, and was totally destroyed in the crash and subsequent fire. Nobody was killed, although the pilot and a passenger were injured. This crash was witnessed b ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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The Twentieth Century Society
The Twentieth Century Society (C20) is a British charity which campaigns for the preservation of architectural heritage from 1914 onwards. The society's interests embrace buildings and artefacts that characterise 20th-century Britain. It is formally recognised as one of the National Amenity Societies, and as such is a statutory consultee on alterations to listed buildings within its period of interest, and must be notified of any proposed work to a listed building which involves any element of demolition. The society was formed as The Thirties Society in 1979, the year in which the prominent "Thirties – British art and design before the War" exhibition was shown at the Hayward Gallery. Its establishment was inspired by and loosely modelled on the Victorian Society, which aims to protect pre-1914 Victorian and Edwardian buildings. Bevis Hillier was the first president, and Clive Aslet the first honorary secretary. In 1992, the society changed its name to The Twentieth Century S ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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King's Pawn Game
The King's Pawn Game is any chess opening starting with the move: :1. e4 It is the most popular opening move in chess, followed by the Queen's Pawn Game. Details about the move and the game plan White opens with the most popular of the twenty possible opening moves. Although effective in winning for White (54.25%), it is not quite as successful as the four next most common openings for White: 1.d4 (55.95%), 1.Nf3 (55.8%), 1.c4 (56.3%), and 1.g3 (55.8%). Since nearly all openings beginning 1.e4 have names of their own, the term ''King's Pawn Game,'' unlike Queen's Pawn Game, is rarely used to describe the opening of the game. Advancing the king's pawn two squares is highly useful because it occupies a square, attacks the center square d5, and allows the of White's and queen. Chess grandmaster Bobby Fischer said that the King's Pawn Game is "Best by test", and proclaimed that "With 1.e4! I win." Opening categorization and continuations King's Pawn Games are further cl ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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OMX Copenhagen 20
The OMX Copenhagen 25 (), formerly KFX and OMXC20) is the top-tier stock market index for Nasdaq Copenhagen, which is part of the Nasdaq Nordic Nasdaq Nordic is the common name for the subsidiaries of Nasdaq, Inc. that provide financial services and operate marketplaces for securities in the Nordic and Baltic regions of Europe. Historically, the operations were known by the company ..., prior being replaced (as of December 2017) was known as OMX Copenhagen 20 index. It is a market value weighted index that consists of the 25 most-traded stock classes. Components The following 25 listings make up the index as of January 2021. Footnotes External links Bloomberg page for KFX:IND Official OMX Copenhagen 25 composition [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Bill C-20
Bill C-20 refers to various legislation introduced into the House of Commons of Canada, including: * Clarity Act, relating to the secession of a province, introduced in 1999 to the second session of the 36th Parliament * An Act to amend the Criminal Code (protection of children and other vulnerable persons) and the Canada Evidence Act, introduced in 2002 to the second session of the 37th Canadian Parliament; not passed but subsequently re-introduced * Fair Representation Act (Canada) The ''Fair Representation Act'' was an act of the Parliament of Canada and was passed by the 41st Canadian Parliament in 2011. The Act was introduced as Bill C-20 with the long title ''An Act to amend the Constitution Act, 1867, the Electoral B ..., concerning redistribution, introduced in 2011 to the first session of the 41st Parliament {{SIA Canadian federal legislation ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Gulfstream IV
The Gulfstream IV (or G-IV or GIV) and derivatives are a family of twinjet aircraft, mainly for private or business use. They were designed and built by Gulfstream Aerospace, a General Dynamics company based in Savannah, Georgia, United States, from 1985 until 2018. Aircraft power is provided by two Rolls-Royce RB.183 Tay turbofans. Upon delivery of the last G450, over 900 GIV/GIV-SP/G450 units had been produced. The last G450 was delivered on 19 January 2018 after 365 deliveries over 12 years, ending a 30-year production run, to be replaced by the G500. Development Gulfstream, in collaboration with Grumman, began work on the Gulfstream IV in March 1983 as a re-engined, stretched fuselage derivative of the Gulfstream III. The first GIV made its maiden flight on September 19, 1985. The model received type certification from the FAA on April 22, 1987. The G-IV entered into service with serial number 1000 in 1987 and was upgraded to the special purpose ''GIV-SP'' version at se ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Gulfstream III
The Gulfstream III, a business jet produced by Gulfstream Aerospace, is an improved variant of the Grumman Gulfstream II. Design and development The Gulfstream III was built at Savannah, Georgia, in the United States and was designed as an improved variant of the Grumman Gulfstream II. Design studies were performed by Grumman Aerospace Corporation in collaboration with Gulfstream American Corporation. Design of the Gulfstream III started with an effort to synthesize a completely new wing employing NASA supercritical airfoil sections and winglets. Optimization studies considering weight, drag, fuel volume, cost, and performance indicated that a substantial portion of the new wing benefit could be secured with modifications to the existing wing. As a result, the new wing concept was canceled and work began on design modifications that would retain the Gulfstream II wing box structure and trailing edge surfaces. Compared to the G-1159 Gulfstream II, the wing has more span and ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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SL C20
The SL C20 is a type of subway train used in the Stockholm metro, Sweden. Between 1997 and 2004, 271 3-car sets, numbered 2000–2270, were delivered to Stockholm by the former Kalmar Verkstad, owned by Adtranz, later acquired by Bombardier Transportation. The C20 is a completely new design and therefore is not compatible with other train types in the system. At , each carriage is longer than the previous train types. To save cost and weight, each unit has only four bogies. The middle car has two bogies. The end parts consist of one bogie each and are connected to the central portion via a semi-trailer-direction. Trolley subframes are made of stainless steel, and are less susceptible to corrosion. When the C20 was sold as the ''Vagn 2000'' ( en, Wagon 2000), it was marketed as the subway car of the future. All C20 coaches have been given their own names, all proposed by private individuals. Many of the names are linked to Stockholm; for example, coach no. 2001 was christened B ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Fullerene
A fullerene is an allotrope of carbon whose molecule consists of carbon atoms connected by single and double bonds so as to form a closed or partially closed mesh, with fused rings of five to seven atoms. The molecule may be a hollow sphere, ellipsoid, tube, or many other shapes and sizes. Graphene (isolated atomic layers of graphite), which is a flat mesh of regular hexagonal rings, can be seen as an extreme member of the family. Fullerenes with a closed mesh topology are informally denoted by their empirical formula C''n'', often written C''n'', where ''n'' is the number of carbon atoms. However, for some values of ''n'' there may be more than one isomer. The family is named after buckminsterfullerene (C60), the most famous member, which in turn is named after Buckminster Fuller. The closed fullerenes, especially C60, are also informally called buckyballs for their resemblance to the standard ball of association football ("soccer"). Nested closed fullerenes have been named ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Sauber C20
The Sauber C20 was the car with which the Sauber Formula One team competed in the 2001 Formula One season. It was powered by a Petronas-branded '01A' 3.0-litre V10, supplied by Scuderia Ferrari. The C20 was notable not only for its eventual position in the Constructors' World Championship but also for a new type of front suspension mounting: the "twin keel". The twin keel The effect of airflow underneath the nose had first become apparent in the early 1990s. By the end of the decade, most teams had settled for a design where both lower front suspension arms were mounted from a single longitudinal "keel" running underneath the nose. For 2001, the FIA introduced a regulation lifting the sides of the front wing by 50mm, in order to reduce downforce and cut cornering speeds. Sauber had introduced separate pylons for each of the front suspension mounts on their previous car, the C19. For the C20, the area between the front and back mounting points on each side was filled in, creating ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Colt Canada C20 DMR
The Colt Canada C20 DMR is a 7.62×51mm NATO designated marksman rifle created by Colt Canada, in response to a request by the Canadian Armed Forces to replace their earlier 5.56mm C8 carbine in sniper sections. The weapon is intended to enter service in the Canadian and Danish militaries, beginning in 2021. C20 rifles are fitted with the Schmidt & Bender 3-20×50 Ultra Short riflescope. Design The C20 DMR is a semi-automatic rifle that uses 20-round 7.62×51mm NATO box magazines. A major part of its design philosophy was making sure that it was reliable in extreme conditions, such as those specified in the NATO D/14 standards for safety, in which aspects of the weapon such as the kinematics, safety features, recoil, and barrel strength are put under the most severe strain. During these tests, the C20 fired 8,000 rounds without any stoppages and achieved an accuracy of 0.66 MOA over 144 five round groups. The C20 DMR barrel features 4 groove rifling with a 1:254 mm (1 in 10 in) ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |