Results 21 to 30 of about 1,698 (255)
A Theoretical Foundation for Syntactico-Semantic Pattern Recognition
IEEE Access, 2021 Conventionally syntactic pattern recognition tasks have been driven by grammars defining a syntactic structure. Syntactic Pattern recognition tasks were primarily relying on the ability of parsing algorithms to recognize the patterns in the input data ...
Shrinivasan Patnaikuni, Sachin Gengaje
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Grammar Compression with Probabilistic Context-Free Grammar [PDF]
2020 Data Compression Conference (DCC), 2020 We propose a new approach for universal lossless text compression, based on grammar compression. In the literature, a target string $T$ has been compressed as a context-free grammar $G$ in Chomsky normal form satisfying $L(G) = \{T\}$. Such a grammar is often called a \emph{straight-line program} (SLP).
Naganuma, Hiroaki +4 more
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Grammars with two-sided contexts [PDF]
Electronic Proceedings in Theoretical Computer Science, 2014 In a recent paper (M. Barash, A. Okhotin, "Defining contexts in context-free grammars", LATA 2012), the authors introduced an extension of the context-free grammars equipped with an operator for referring to the left context of the substring being ...
Mikhail Barash, Alexander Okhotin
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Learning Cover Context-Free Grammars from Structural Data [PDF]
Scientific Annals of Computer Science, 2014 We consider the problem of learning an unknown context-free gram- mar from its structural descriptions with depth at most ℓ. The structural descriptions of the context-free grammar are its unlabelled derivation trees. The goal is to learn a cover context-
M. Marin, G. Istrate
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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.
Cremers, Armin, Ginsburg, Seymour
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Undecidable problems concerning densities of languages [PDF]
Discrete Mathematics & Theoretical Computer Science, 2005 In this paper we prove that the question whether a language presented by a context free grammar has density, is undecidable. Moreover we show that there is no algorithm which, given two unambiguous context free grammars on input, decides whether the ...
Jakub Kozik
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Weighted Context-Free Grammars Over Bimonoids
Scientific Annals of Computer Science, 2019 We introduce and investigate weighted context-free grammars over an arbitrary bimonoid K. Thus, we do not assume that the operations of K are commutative or idempotent or they distribute over each other.
George Rahonis, Faidra Torpari
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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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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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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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