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Eilenberg Machine
The X-machine (''XM'') is a theoretical model of computation introduced by Samuel Eilenberg in 1974.S. Eilenberg (1974) ''Automata, Languages and Machines, Vol. A''. Academic Press, London. The ''X'' in "X-machine" represents the fundamental data type on which the machine operates; for example, a machine that operates on databases (objects of type ''database'') would be a ''database''-machine. The X-machine model is structurally the same as the finite-state machine, except that the symbols used to label the machine's transitions denote relations of type ''X''→''X''. Crossing a transition is equivalent to applying the relation that labels it (computing a set of changes to the data type ''X''), and traversing a path in the machine corresponds to applying all the associated relations, one after the other. Original theory Eilenberg's original X-machine was a completely general theoretical model of computation (subsuming the Turing machine, for example), which admitted determin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Computation
Computation is any type of arithmetic or non-arithmetic calculation that follows a well-defined model (e.g., an algorithm). Mechanical or electronic devices (or, historically, people) that perform computations are known as '' computers''. An especially well-known discipline of the study of computation is computer science. Physical process of Computation Computation can be seen as a purely physical process occurring inside a closed physical system called a computer. Examples of such physical systems are digital computers, mechanical computers, quantum computers, DNA computers, molecular computers, microfluidics-based computers, analog computers, and wetware computers. This point of view has been adopted by the physics of computation, a branch of theoretical physics, as well as the field of natural computing. An even more radical point of view, pancomputationalism (inaudible word), is the postulate of digital physics that argues that the evolution of the universe is itself ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
X-Machine Testing
The (Stream) X-Machine Testing Methodology is a ''complete'' functional testing approach to software- and hardware testingM. Holcombe and F. Ipate (1998) ''Correct Systems - Building a Business Process Solution''. Springer, Applied Computing Series. that exploits the scalability of the Stream X-Machine model of computation.Gilbert Laycock (1993) ''The Theory and Practice of Specification Based Software Testing''. PhD Thesis, University of SheffieldAbstract Using this methodology, it is likely to identify a finite test-set that exhaustively determines whether the tested system's implementation matches its specification. This goal is achieved by a divide-and-conquer approach, in which the design is decomposed by refinementF. Ipate and M. Holcombe (1998) 'A method for refining and testing generalised machine specifications'. ''Int. J. Comp. Math.'' 68, pp. 197–219. into a collection of Stream X-Machines, which are implemented as separate modules, then tested bottom-up. At each ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
IATA
The International Air Transport Association (IATA ) is a trade association of the world's airlines founded in 1945. IATA has been described as a cartel since, in addition to setting technical standards for airlines, IATA also organized tariff conferences that served as a forum for price fixing. Consisting in 2016 of 290 airlines, primarily major carriers, representing 117 countries, the IATA's member airlines account for carrying approximately 82% of total available seat miles air traffic. IATA supports airline activity and helps formulate industry policy and standards. It is headquartered in Canada in the city of Montréal, with executive offices in Geneva, Switzerland. History IATA was formed in April 1945 in Havana, Cuba. It is the successor to the International Air Traffic Association, which was formed in 1919 at The Hague, Netherlands. At its founding, IATA consisted of 57 airlines from 31 countries. Much of IATA's early work was technical and IATA provided input to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
SXM (computational Model)
SXM may refer to: * SXM (computational model), model for a Stream X-Machine * SXM (transactional memory), a software under development at Microsoft Research * SXM (socket), a physical computer interface used by Nvidia computational GPU modules * SXM inc, a digital studio producing online entertainment for brands * Sint Maarten's ISO 3166-1 alpha-3 code ** Princess Juliana International Airport's IATA code ** Sint Maarten national football team's FIFA code * Sirius XM Radio's NYSE symbol * Servicios Aéreos Especializados Mexicanos's ICAO code * Starbury SXM, a basketball shoe produced by Starbury * ''SxM'', a 1994 album by Sangue Misto * SxM, formats of scanning microscope image handled by Image SXM * sxm, file extension for math files from StarOffice's StarMath (version 1–7) * sxm, file extension for math files from OpenOffice.org XML OpenOffice.org XML is an open XML-based file format developed as an open community effort by Sun Microsystems in 2000–2002. The open-sourc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hypercomputation
Hypercomputation or super-Turing computation refers to models of computation that can provide outputs that are not Turing-computable. Super-Turing computing, introduced at the early 1990's by Hava Siegelmann, refers to such neurological inspired, biological and physical realizable computing; It became the mathematical foundations of Lifelong Machine Learning. Hypercomputation, introduced as a field of science in the late 1990s, is said to be based on the Super Turing but it also includes constructs which are philosophical. For example, a machine that could solve the halting problem would be a hypercomputer; so too would one that can correctly evaluate every statement in Peano arithmetic. The Church–Turing thesis states that any "computable" function that can be computed by a mathematician with a pen and paper using a finite set of simple algorithms, can be computed by a Turing machine. Hypercomputers compute functions that a Turing machine cannot and which are, hence, not comput ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
NASA
The National Aeronautics and Space Administration (NASA ) is an independent agency of the US federal government responsible for the civil space program, aeronautics research, and space research. NASA was established in 1958, succeeding the National Advisory Committee for Aeronautics (NACA), to give the U.S. space development effort a distinctly civilian orientation, emphasizing peaceful applications in space science. NASA has since led most American space exploration, including Project Mercury, Project Gemini, the 1968-1972 Apollo Moon landing missions, the Skylab space station, and the Space Shuttle. NASA supports the International Space Station and oversees the development of the Orion spacecraft and the Space Launch System for the crewed lunar Artemis program, Commercial Crew spacecraft, and the planned Lunar Gateway space station. The agency is also responsible for the Launch Services Program, which provides oversight of launch operations and countdown m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gerard Huet
Gerard is a masculine forename of Proto-Germanic origin, variations of which exist in many Germanic and Romance languages. Like many other early Germanic names, it is dithematic, consisting of two meaningful constituents put together. In this case, those constituents are ''gari'' > ''ger-'' (meaning 'spear') and -''hard'' (meaning 'hard/strong/brave'). Common forms of the name are Gerard (English, Scottish, Irish, Dutch, Polish and Catalan); Gerrard (English, Scottish, Irish); Gerardo ( Italian, and Spanish); Geraldo ( Portuguese); Gherardo ( Italian); Gherardi ( Northern Italian, now only a surname); Gérard (variant forms ''Girard'' and ''Guérard'', now only surnames, French); Gearóid ( Irish); Gerhardt and Gerhart/Gerhard/Gerhardus ( German, Dutch, and Afrikaans); Gellért ( Hungarian); Gerardas (Lithuanian) and Gerards/Ģirts ( Latvian); Γεράρδης ( Greece). A few abbreviated forms are Gerry and Jerry (English); Gerd (German) and Gert (Afrikaans and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pāṇini
, era = ;;6th–5th century BCE , region = Indian philosophy , main_interests = Grammar, linguistics , notable_works = ' ( Classical Sanskrit) , influenced= , notable_ideas= Descriptive linguistics (Devanagari: पाणिनि, ) was a Sanskrit philologist, grammarian, and revered scholar in ancient India, variously dated between the 6th and 4th century BCE. Since the discovery and publication of his work by European scholars in the nineteenth century, Pāṇini has been considered the "first descriptive linguist", François & Ponsonnet (2013: 184). and even labelled as “the father of linguistics”. Pāṇini's grammar was influential on such foundational linguists as Ferdinand de Saussure and Leonard Bloomfield. Legacy Pāṇini is known for his text '' Aṣṭādhyāyī'', a sutra-style treatise on Sanskrit grammar, 3,996 verses or rules on linguistics, syntax and semantics in "eight chapters" which is the foundational text of th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lexical Semantics
Lexical semantics (also known as lexicosemantics), as a subfield of linguistics, linguistic semantics, is the study of word meanings.Pustejovsky, J. (2005) Lexical Semantics: Overview' in Encyclopedia of Language and Linguistics, second edition, Volumes 1-14Taylor, J. (2017) Lexical Semantics'. In B. Dancygier (Ed.), The Cambridge Handbook of Cognitive Linguistics (Cambridge Handbooks in Language and Linguistics, pp. 246-261). Cambridge: Cambridge University Press. It includes the study of how words structure their meaning, how they act in grammar and Principle of compositionality, compositionality, and the relationships between the distinct senses and uses of a word. The units of analysis in lexical semantics are lexical units which include not only words but also sub-words or sub-units such as affixes and even compound words and phrases. Lexical units include the catalogue of words in a language, the lexicon. Lexical semantics looks at how the meaning of the lexical units correl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Samuel Eilenberg
Samuel Eilenberg (September 30, 1913 – January 30, 1998) was a Polish-American mathematician who co-founded category theory (with Saunders Mac Lane) and homological algebra. Early life and education He was born in Warsaw, Kingdom of Poland to a Jewish family. He spent much of his career as a professor at Columbia University. He earned his Ph.D. from University of Warsaw in 1936, with thesis ''On the Topological Applications of Maps onto a Circle''; his thesis advisors were Kazimierz Kuratowski and Karol Borsuk. He died in New York City in January 1998. Career Eilenberg's main body of work was in algebraic topology. He worked on the axiomatic treatment of homology theory with Norman Steenrod (and the Eilenberg–Steenrod axioms are named for the pair), and on homological algebra with Saunders Mac Lane. In the process, Eilenberg and Mac Lane created category theory. Eilenberg was a member of Bourbaki and, with Henri Cartan, wrote the 1956 book ''Homological Algebra''. La ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Communicating X-Machine
The Communicating (Stream) X-Machine is a model of computation introduced by various researchers in the 1990s to model systems composed of communicating agents. The model exists in several variants, which are either based directly on Samuel Eilenberg's X-machineS. Eilenberg (1974) ''Automata, Languages and Machines, Vol. A''. Academic Press, London. or on Gilbert Laycock's later Stream X-Machine The Stream X-machine (SXM) is a model of computation introduced by Gilbert Laycock in his 1993 PhD thesis, ''The Theory and Practice of Specification Based Software Testing''.Gilbert Laycock (1993) ''The Theory and Practice of Specification Based ....Gilbert Laycock (1993) ''The Theory and Practice of Specification Based Software Testing''. PhD Thesis, University of Sheffield. Abstract{{Webarchive, url=https://web.archive.org/web/20071105145328/http://www.mcs.le.ac.uk/people/gtl1/PhDabstract.html , date=2007-11-05 References Theory of computation Models of computation< ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
