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Janusz Brzozowski (computer Scientist)
Janusz (John) Antoni Brzozowski (May 10, 1935 – October 24, 2019) was a Polish-Canadian computer scientist and Distinguished Professor Emeritus at the University of Waterloo's David R. Cheriton School of Computer Science. In 1962, Brzozowski earned his PhD in the field of electrical engineering at Princeton University under Edward J. McCluskey. The topic of the thesis was ''Regular Expression Techniques for Sequential Circuits''. From 1967 to 1996 he was Professor at the University of Waterloo. He is known for his contributions to mathematical logic, circuit theory, and automata theory. Achievements in research Brzozowski worked on regular expressions and on syntactic semigroups of formal languages.Pin (1997) The result was ''Characterizations of locally testable events'' written together with Imre Simon, which had a similar impact on the development of the algebraic theory of formal languages as Marcel-Paul Schützenberger's characterization of the star-free languages. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Warsaw, Poland
Warsaw ( pl, Warszawa, ), officially the Capital City of Warsaw,, abbreviation: ''m.st. Warszawa'' is the capital and List of cities and towns in Poland, largest city of Poland. The metropolis stands on the Vistula, River Vistula in east-central Poland, and its population is officially estimated at 1.86 million residents within a Warsaw metropolitan area, greater metropolitan area of 3.1 million residents, which makes Warsaw the List of cities in the European Union by population within city limits, 7th most-populous city in the European Union. The city area measures and comprises Districts and neighbourhoods of Warsaw, 18 districts, while the metropolitan area covers . Warsaw is an Alpha global city, a major cultural, political and Financial centre, economic hub, and the country's seat of government. Warsaw traces its origins to a small Fishing village, fishing town in Masovia. The city rose to prominence in the late 16th century, when Sigismund III decided to move ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Regular Expressions
A regular expression (shortened as regex or regexp; sometimes referred to as rational expression) is a sequence of characters that specifies a search pattern in text. Usually such patterns are used by string-searching algorithms for "find" or "find and replace" operations on strings, or for input validation. Regular expression techniques are developed in theoretical computer science and formal language theory. The concept of regular expressions began in the 1950s, when the American mathematician Stephen Cole Kleene formalized the concept of a regular language. They came into common use with Unix text-processing utilities. Different syntaxes for writing regular expressions have existed since the 1980s, one being the POSIX standard and another, widely used, being the Perl syntax. Regular expressions are used in search engines, in search and replace dialogs of word processors and text editors, in text processing utilities such as sed and AWK, and in lexical analysis. Most gener ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Journal Of The ACM
The ''Journal of the ACM'' is a peer-reviewed scientific journal covering computer science in general, especially theoretical aspects. It is an official journal of the Association for Computing Machinery. Its current editor-in-chief is Venkatesan Guruswami. The journal was established in 1954 and "computer scientists universally hold the ''Journal of the ACM'' in high esteem". See also * ''Communications of the ACM ''Communications of the ACM'' is the monthly journal of the Association for Computing Machinery (ACM). It was established in 1958, with Saul Rosen as its first managing editor. It is sent to all ACM members. Articles are intended for readers with ...'' References External links * Publications established in 1954 Computer science journals Association for Computing Machinery academic journals Bimonthly journals English-language journals {{compu-journal-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lila Kari
Lila Kari (née Sântean) is a Romanian and Canadian computer scientist, professor in the David R. Cheriton School of Computer Science at the University of Waterloo, Canada. Biography Professor Kari earned a master's degree at the University of Bucharest in 1987, studying there with Gheorghe Păun, and then moved to the University of Turku in Finland for her graduate studies, earning a Ph.D. in 1991 under the supervision of Arto Salomaa. She came to the University of Western Ontario as a visiting professor in 1993, and by 1996 had been hired there as a tenure-track faculty member.. In 2017 she accepted a position of professor of computer science and University Research Chair at the University of Waterloo. Research Kari's thesis research was in formal language theory. In the mid-1990s, inspired by an article by Leonard Adleman in ''Science'', she shifted her interests to DNA computing. In her research, together with Laura Landweber, she has initiated and explored the study of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Computing Research Association
The Computing Research Association (CRA) is a 501(c)3 non-profit association of North American academic departments of computer science, computer engineering, and related fields; laboratories and centers in industry, government, and academia engaging in basic computing research; and affiliated professional societies. CRA was formed in 1972 and is based in Washington, D.C., United States. Mission and activities CRA's mission is to enhance innovation by joining with industry, government and academia to strengthen research and advanced education in computing. CRA executes this mission by leading the computing research community, informing policymakers and the public, and facilitating the development of strong, diverse talent in the field. Policy CRA assists policymakers who seek to understand the issues confronting the federal Networking and Information Technology Research and Development (NITRD) program, a thirteen-agency, $4-billion-a-year federal effort to support computing res ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ehrenfeucht–Fraïssé Game
In the mathematical discipline of model theory, the Ehrenfeucht–Fraïssé game (also called back-and-forth games) is a technique based on game semantics for determining whether two structures are elementarily equivalent. The main application of Ehrenfeucht–Fraïssé games is in proving the inexpressibility of certain properties in first-order logic. Indeed, Ehrenfeucht–Fraïssé games provide a complete methodology for proving inexpressibility results for first-order logic. In this role, these games are of particular importance in finite model theory and its applications in computer science (specifically computer aided verification and database theory), since Ehrenfeucht–Fraïssé games are one of the few techniques from model theory that remain valid in the context of finite models. Other widely used techniques for proving inexpressibility results, such as the compactness theorem, do not work in finite models. Ehrenfeucht–Fraïssé-like games can also be defined for othe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
First-order Logic
First-order logic—also known as predicate logic, quantificational logic, and first-order predicate calculus—is a collection of formal systems used in mathematics, philosophy, linguistics, and computer science. First-order logic uses quantified variables over non-logical objects, and allows the use of sentences that contain variables, so that rather than propositions such as "Socrates is a man", one can have expressions in the form "there exists x such that x is Socrates and x is a man", where "there exists''"'' is a quantifier, while ''x'' is a variable. This distinguishes it from propositional logic, which does not use quantifiers or relations; in this sense, propositional logic is the foundation of first-order logic. A theory about a topic is usually a first-order logic together with a specified domain of discourse (over which the quantified variables range), finitely many functions from that domain to itself, finitely many predicates defined on that domain, and a set of ax ... [...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''. Later ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Regular Expression
A regular expression (shortened as regex or regexp; sometimes referred to as rational expression) is a sequence of characters that specifies a search pattern in text. Usually such patterns are used by string-searching algorithms for "find" or "find and replace" operations on strings, or for input validation. Regular expression techniques are developed in theoretical computer science and formal language theory. The concept of regular expressions began in the 1950s, when the American mathematician Stephen Cole Kleene formalized the concept of a regular language. They came into common use with Unix text-processing utilities. Different syntaxes for writing regular expressions have existed since the 1980s, one being the POSIX standard and another, widely used, being the Perl syntax. Regular expressions are used in search engines, in search and replace dialogs of word processors and text editors, in text processing utilities such as sed and AWK, and in lexical analysis. Most gener ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Star-free Language
A regular language is said to be star-free if it can be described by a regular expression constructed from the letters of the alphabet, the empty set symbol, all boolean operators – including complementation – and concatenation but no Kleene star.Lawson (2004) p.235 For instance, the language of words over the alphabet \ that do not have consecutive a's can be defined by (\emptyset^c aa \emptyset^c)^c, where X^c denotes the complement of a subset X of \^*. The condition is equivalent to having generalized star height zero. An example of a regular language which is not star-free is \, i.e. the language of strings consisting of an even number of "a". Marcel-Paul Schützenberger characterized star-free languages as those with aperiodic syntactic monoids.Lawson (2004) p.262 They can also be characterized logically as languages definable in FO the first-order logic over the natural numbers with the less-than relation, as the counter-free languages and as languages defin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Marcel-Paul Schützenberger
Marcel-Paul "Marco" Schützenberger (24 October 1920 – 29 July 1996) was a French mathematician and Doctor of Medicine. He worked in the fields of formal language, combinatorics, and information theory.Herbert Wilf, Dominique Foata, ''et al.'',In Memoriam: Marcel-Paul Schützenberger, 1920-1996," ''Electronic Journal of Combinatorics'', served from University of Pennsylvania Dept. of Mathematics Server, article dated 12 October 1996, retrieved from WWW on 4 November 2006. In addition to his formal results in mathematics, he was "deeply involved in struggle against the votaries of eo-arwinism",Foata, Dominique, "In Memoriam," ''op. cit.'' a stance which has resulted in some mixed reactions from his peers and from critics of his stance on evolution. Several notable theorems and objects in mathematics as well as computer science bear his name (for example Schutzenberger group or the Chomsky–Schützenberger hierarchy). Paul Schützenberger was his great-grandfather. In the lat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
