Results 21 to 30 of about 1,739 (253)
Grammar-Based Recognition of Documentary Forms and Extraction of Metadata
International Journal of Digital Curation, 2010 Metadata extraction is a critical aspect of ingestion of collections into digital archives and libraries. A method for automatically recognizing document types and extracting metadata from digital records has been developed.
William Underwood
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Subgraph Queries by Context-free Grammars
Journal of Integrative Bioinformatics, 2008 We describe a method for querying vertex- and edge-labeled graphs using context-free grammars to specify the class of interesting paths. We introduce a novel problem, finding the connection subgraph induced by the set of matching paths between given two ...
Sevon Petteri, Eronen Lauri
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Context-Free Tree Grammars are as Powerful as Context-Free Jungle Grammars
Acta Cybernetica, 2015 Jungles generalize trees by sharing subtrees and allowing garbage. It is shown that IO context-free tree grammars generate the same jungle languages as context-free jungle grammars.
Drewes, F., Engelfriet, J.
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Journal of Computer and System Sciences, 1974 In an attempt to provide a unified theory of grammars, a model is introduced which has two components. The first is a ''grammar form,'' which provides the general structure of the productions in the grammars to be defined. The second is an ''interpretation'', which yields a specific grammar.
Armin B. Cremers, Seymour Ginsburg
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Path querying using conjunctive grammars
Труды Института системного программирования РАН, 2018 Graphs are used as a data structure to represent large volumes of information in a compact and convenient for analysis form in many areas: bioinformatics, graph databases, static code analysis, etc.
R. Sh. Azimov, S. V. Grigorev
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Macros for context-free grammars [PDF]
Proceedings of the 10th international ACM SIGPLAN conference on Principles and practice of declarative programming, 2008 Current parser generators are based on context-free grammars. Because such grammars lack abstraction facilities, the resulting specifications are often not easy to read. Fischer's macro grammars extend context-free grammars with macro-like productions thus providing the equivalent of procedural abstraction. However, their use is hampered by the lack of
Peter Thiemann 0001, Matthias Neubauer
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Concurrent Context-Free Grammars [PDF]
, 2013 In this paper we study some properties of context-free concurrent grammars which are controlled by Petri nets under parallel firing strategies, i.e., the transitions of a Petri net fire simultaneously in different modes. These variants of control increase the computational power of generative devices.
Gairatzhan Mavlankulov +3 more
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Binary Context-Free Grammars [PDF]
Symmetry, 2020 A binary grammar is a relational grammar with two nonterminal alphabets, two terminal alphabets, a set of pairs of productions and the pair of the initial nonterminals that generates the binary relation, i.e., the set of pairs of strings over the terminal alphabets.
Sherzod Turaev +4 more
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Generative Power and Closure Properties of Watson-Crick Grammars
Applied Computational Intelligence and Soft Computing, 2016 We define WK linear grammars, as an extension of WK regular grammars with linear grammar rules, and WK context-free grammars, thus investigating their computational power and closure properties.
Nurul Liyana Mohamad Zulkufli +3 more
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Reduction of context-free grammars
Information and Control, 1970 This paper is concerned with the following problem: Given a context-free grammar G, find a context-free grammar with the fewest nonterminal symbols or with the fewest rules that is equivalent to G. A reduction procedure is presented for finding such a reduced context-free grammar that is structurally equivalent to a given G.
Kenichi Taniguchi, Tadao Kasami
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