Results 31 to 40 of about 304,382 (268)
Iso-array rewriting P systems with context-free iso-array rules [PDF]
, 2014 A new computing model called P system is a highly distributed and parallel theoretical model, which is proposed in the area of membrane computing. Ceterchi et al.
Bhuvaneswari, K. +4 more
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Complexity of Problems of Commutative Grammars [PDF]
Logical Methods in Computer Science, 2015 We consider commutative regular and context-free grammars, or, in other words, Parikh images of regular and context-free languages. By using linear algebra and a branching analog of the classic Euler theorem, we show that, under an assumption that the ...
Eryk Kopczynski
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From left-regular to Greibach normal form grammars [PDF]
, 1979 Each context-free grammar can be transformed to a context-free grammar in Greibach normal form, that is, a context-free grammar where each right-hand side of a prorfuction begins with a terminal symbol and the remainder of the right-hand side consists of
Nijholt, A.
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Fatgraph models of RNA structure
Computational and Mathematical Biophysics, 2017 In this review paper we discuss fatgraphs as a conceptual framework for RNA structures. We discuss various notions of coarse-grained RNA structures and relate them to fatgraphs.We motivate and discuss the main intuition behind the fatgraph model and ...
Huang Fenix +2 more
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On the Order Type of Scattered Context-Free Orderings [PDF]
Electronic Proceedings in Theoretical Computer Science, 2019 We show that if a context-free grammar generates a language whose lexicographic ordering is well-ordered of type less than ω^2, then its order type is effectively computable.
Kitti Gelle, Szabolcs Iván
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On the covering of left recursive grammars [PDF]
, 1976 In this paper we show that some prevailing ideas on the elimination of left recursion in a context-free grammar are not valid. An algorithm and a proof are given to show that every proper context-free grammar is covered by a non-left-recursive ...
Nijholt, A.
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An Online Algorithm for Lightweight Grammar-Based Compression
Algorithms, 2012 Grammar-based compression is a well-studied technique to construct a context-free grammar (CFG) deriving a given text uniquely. In this work, we propose an online algorithm for grammar-based compression.
Masayuki Takeda +2 more
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The Triple-Pair Construction for Weighted ω-Pushdown Automata [PDF]
Electronic Proceedings in Theoretical Computer Science, 2017 Let S be a complete star-omega semiring and Sigma be an alphabet. For a weighted omega-pushdown automaton P with stateset 1...n, n greater or equal to 1, we show that there exists a mixed algebraic system over a complete semiring-semimodule pair ((S ...
Manfred Droste +2 more
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Consistent Unsupervised Estimators for Anchored PCFGs
Transactions of the Association for Computational Linguistics, 2020 Learning probabilistic context-free grammars (PCFGs) from strings is a classic problem in computational linguistics since Horning ( 1969 ). Here we present an algorithm based on distributional learning that is a consistent estimator for a large class of ...
Clark, Alexander, Fijalkow, Nathanaël
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Data-oriented parsing with discontinuous constituents and function tags
Journal of Language Modelling, 2016 Statistical parsers are e ective but are typically limited to producing projective dependencies or constituents. On the other hand, linguisti- cally rich parsers recognize non-local relations and analyze both form and function phenomena but rely on ...
Andreas van Cranenburgh +2 more
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