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Witold Lipski
Witold Lipski Jr. (July 13, 1949, in Warsaw, Poland – May 30, 1985, in Nantes, France) was a Polish computer scientist (habilitation in computer science), and an author of two books: ''Combinatorics for Programmers'' (two editions) and (jointly with Wiktor Marek ''Combinatorial analysis''. Lipski, jointly with his PhD student, Tomasz Imieliński, created foundations of the theory of incomplete information in relational databases. Life Lipski graduated from the Program of Fundamental Problems of Technology, at the Warsaw Technical University. He received a Ph.D. in computer science at the Computational Center (later: Institute for Computer Science) of the Polish Academy of Sciences, under supervision of Prof. Wiktor Marek. Lipski's dissertation was on the topic of information storage and retrieval systems and titled 'Combinatorial Aspects of Information Retrieval'. His habilitation was granted by the Institute of Computer Science of Polish Academy of Sciences. Lipski spent a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Warsaw
Warsaw ( pl, Warszawa, ), officially the Capital City of Warsaw,, abbreviation: ''m.st. Warszawa'' is the capital and largest city of Poland. The metropolis stands on the River Vistula in east-central Poland, and its population is officially estimated at 1.86 million residents within a greater metropolitan area of 3.1 million residents, which makes Warsaw the 7th most-populous city in the European Union. The city area measures and comprises 18 districts, while the metropolitan area covers . Warsaw is an Alpha global city, a major cultural, political and economic hub, and the country's seat of government. Warsaw traces its origins to a small fishing town in Masovia. The city rose to prominence in the late 16th century, when Sigismund III decided to move the Polish capital and his royal court from Kraków. Warsaw served as the de facto capital of the Polish–Lithuanian Commonwealth until 1795, and subsequently as the seat of Napoleon's Duchy of Warsaw. Th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tomasz Imieliński
Tomasz Imieliński (born July 11, 1954 in Toruń, Poland) is a Polish-American computer scientist, most known in the areas of data mining, mobile computing, data extraction, and search engine technology. He is currently a professor of computer science at Rutgers University in New Jersey, United States. In 2000, he co-founded Connotate Technologies, a web data extraction company based in New Brunswick, NJ. Since 2004 till 2010 he had held multiple positions at Ask.com, from vice president of data solutions intelligence to executive vice president of global search and answers and chief scientist. From 2010 to 2012 he served as VP of data solutions at IAC/ Pronto. Tomasz Imieliński served as chairman of the Computer Science Department at Rutgers University from 1996 to 2003. He co-founded Art Data Laboratories LLC company, and its product, Articker is the largest known database that aggregates dynamic non-price information about the visual artists in the global art market. Artick ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Relational Algebra
In database theory, relational algebra is a theory that uses algebraic structures with a well-founded semantics for modeling data, and defining queries on it. The theory was introduced by Edgar F. Codd. The main application of relational algebra is to provide a theoretical foundation for relational databases, particularly query languages for such databases, chief among which is SQL. Relational databases store tabular data represented as relations. Queries over relational databases often likewise return tabular data represented as relations. The main purpose of the relational algebra is to define operators that transform one or more input relations to an output relation. Given that these operators accept relations as input and produce relations as output, they can be combined and used to express potentially complex queries that transform potentially many input relations (whose data are stored in the database) into a single output relation (the query results). Unary operators ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Edgar Codd
Edgar Frank "Ted" Codd (19 August 1923 – 18 April 2003) was an English computer scientist who, while working for IBM, invented the relational model for database management, the theoretical basis for relational databases and relational database management systems. He made other valuable contributions to computer science, but the relational model, a very influential general theory of data management, remains his most mentioned, analyzed and celebrated achievement. Biography Edgar Frank Codd was born in Fortuneswell, on the Isle of Portland in Dorset, England. After attending Poole Grammar School, he studied mathematics and chemistry at Exeter College, Oxford, before serving as a pilot in the RAF Coastal Command during the Second World War, flying Sunderlands. In 1948, he moved to New York to work for IBM as a mathematical programmer. In 1953, angered by Senator Joseph McCarthy, Codd moved to Ottawa, Ontario, Canada. In 1957 he returned to the US working for IBM and from 1961 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Logical Methods In Computer Science
''Logical Methods in Computer Science'' (LMCS) is a peer-reviewed open access scientific journal covering theoretical computer science and applied logic. It opened to submissions on September 1, 2004. The editor-in-chief is Stefan Milius ( Friedrich-Alexander Universität Erlangen-Nürnberg). History The journal was initially published by the International Federation for Computational Logic, and then by a dedicated non-profit. It moved to the . platform in 2017. The first editor-in-chief was Dana Scott. In its first year, the journal received 75 submissions. Abstracting and indexing The journal is abstracted and indexed in Current Contents/Engineering, Computing & Technology, Mathematical Reviews, Science Citation Index Expanded, Scopus, and Zentralblatt MATH. According to the ''Journal Citation Reports'', the journal has a 2016 impact factor The impact factor (IF) or journal impact factor (JIF) of an academic journal is a scientometric index calculated by Clarivate th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Universal Algebra
Universal algebra (sometimes called general algebra) is the field of mathematics that studies algebraic structures themselves, not examples ("models") of algebraic structures. For instance, rather than take particular groups as the object of study, in universal algebra one takes the class of groups as an object of study. Basic idea In universal algebra, an algebra (or algebraic structure) is a set ''A'' together with a collection of operations on ''A''. An ''n''- ary operation on ''A'' is a function that takes ''n'' elements of ''A'' and returns a single element of ''A''. Thus, a 0-ary operation (or ''nullary operation'') can be represented simply as an element of ''A'', or a '' constant'', often denoted by a letter like ''a''. A 1-ary operation (or ''unary operation'') is simply a function from ''A'' to ''A'', often denoted by a symbol placed in front of its argument, like ~''x''. A 2-ary operation (or ''binary operation'') is often denoted by a symbol placed between its argum ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cylindric Algebra
In mathematics, the notion of cylindric algebra, invented by Alfred Tarski, arises naturally in the algebraization of first-order logic with equality. This is comparable to the role Boolean algebras play for propositional logic. Cylindric algebras are Boolean algebras equipped with additional cylindrification operations that model quantification and equality. They differ from polyadic algebras in that the latter do not model equality. Definition of a cylindric algebra A cylindric algebra of dimension \alpha (where \alpha is any ordinal number) is an algebraic structure (A,+,\cdot,-,0,1,c_\kappa,d_)_ such that (A,+,\cdot,-,0,1) is a Boolean algebra, c_\kappa a unary operator on A for every \kappa (called a ''cylindrification''), and d_ a distinguished element of A for every \kappa and \lambda (called a ''diagonal''), such that the following hold: : (C1) c_\kappa 0=0 : (C2) x\leq c_\kappa x : (C3) c_\kappa(x\cdot c_\kappa y)=c_\kappa x\cdot c_\kappa y : (C4) c_\kappa c_ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
SIGMOD
SIGMOD is the Association for Computing Machinery's Special Interest Group on Management of Data, which specializes in large-scale data management problems and databases. The annual ACM SIGMOD Conference, which began in 1975, is considered one of the most important in the field. While traditionally this conference had always been held within North America, it took place in Paris in 2004, Beijing in 2007, Athens in 2011, and Melbourne in 2015. The acceptance rate of the ACM SIGMOD Conference, averaged from 1996 to 2012, was 18%, and it was 17% in 2012. In association with SIGACT and SIGART, SIGMOD also sponsors the annual ACM Symposium on Principles of Database Systems (PODS) conference on the theoretical aspects of database systems. PODS began in 1982, and has been held jointly with the SIGMOD conference since 1991. Each year, the group gives out several awards to contributions to the field of data management. The most important of these is the SIGMOD Edgar F. Codd Innovations Aw ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Imieliński–Lipski Algebra
In database theory, Imieliński–Lipski algebra is an extension of relational algebra onto tables with different types of null values. It is used to operate on relations with incomplete information. Imieliński–Lipski algebras are defined to satisfy precise conditions for semantically meaningful extension of the usual relational operators, such as projection, selection, union, and join, from operators on relations to operators on relations with various kinds of "null values". These conditions require that the system be ''safe'' in the sense that no incorrect conclusion is derivable by using a specified subset F of the relational operators; and that it be ''complete'' in the sense that all valid conclusions expressible by relational expressions using operators in F are in fact derivable in this system. For example, it is well known that the three-valued logic approach to deal with null values, supported treatment of nulls values by SQL is not complete, see Ullman book. T ... [...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] |
VLDB Conference
International Conference on Very Large Data Bases or VLDB conference is an annual conference held by the non-profit ''Very Large Data Base Endowment Inc.'' While named after very large databases, the conference covers the research and development results in the broader field of database management. The mission of VLDB Endowment is to "promote and exchange scholarly work in databases and related fields throughout the world." The VLDB conference began in 1975 and is now closely associated with SIGMOD and SIGKDD. Venues See also * XLDB XLDB (eXtremely Large DataBases) is a yearly conference about databases, data management and analytics. The definition of ''extremely large'' refers to data sets that are too big in terms of volume (too much), and/or velocity (too fast), and/or va ... References External links VLDB Endowment Inc. {{Authority control Computer science conferences ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
ACM Transactions On Database Systems
The ''ACM Transactions on Database Systems'' (''ACM TODS'') is one of the scientific journal, journals produced by the Association for Computing Machinery. ''TODS'' publishes one volume yearly. Each volume has four issues, which appear in March, June, September and December. The editor-in-chief is Christopher Jermaine (Rice University). Abstracting and indexing According to the ''Journal Citation Reports'', the journal had a 2020 impact factor of 1.086. It is indexed in the following bibliographic databases: *Ei Compendex *SCImago Journal Rank, SCImago *Scopus *ProQuest SciTech Premium Collection *Web of Science References External links Journal homepage Computer science journals Association for Computing Machinery academic journals, Transactions on Database Systems Hybrid open access journals {{compu-journal-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
