Results 11 to 20 of about 304,382 (268)
Implicit learning of recursive context-free grammars. [PDF]
PLoS ONE, 2012 Context-free grammars are fundamental for the description of linguistic syntax. However, most artificial grammar learning experiments have explored learning of simpler finite-state grammars, while studies exploring context-free grammars have not assessed
Martin Rohrmeier +2 more
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LPG–PCFG: An Improved Probabilistic Context- Free Grammar to Hit Low-Probability Passwords [PDF]
Sensors, 2022 With the development of the Internet, information security has attracted more attention. Identity authentication based on password authentication is the first line of defense; however, the password-generation model is widely used in offline password ...
Xiaozhou Guo +4 more
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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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A stochastic context free grammar based framework for analysis of protein sequences [PDF]
BMC Bioinformatics, 2009 Background In the last decade, there have been many applications of formal language theory in bioinformatics such as RNA structure prediction and detection of patterns in DNA.
Nebel Jean-Christophe, Dyrka Witold
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On the Size Complexity of Non-Returning Context-Free PC Grammar Systems [PDF]
Electronic Proceedings in Theoretical Computer Science, 2009 Improving the previously known best bound, we show that any recursively enumerable language can be generated with a non-returning parallel communicating (PC) grammar system having six context-free components.
Erzsébet Csuhaj-Varjú, György Vaszil
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Multiplicative-Additive Focusing for Parsing as Deduction [PDF]
Electronic Proceedings in Theoretical Computer Science, 2015 Spurious ambiguity is the phenomenon whereby distinct derivations in grammar may assign the same structural reading, resulting in redundancy in the parse search space and inefficiency in parsing.
Glyn Morrill, Oriol Valentín
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Cross-Domain Feature Enhancement-Based Password Guessing Method for Small Samples [PDF]
EntropyAs a crucial component of account protection system evaluation and intrusion detection, the advancement of password guessing technology encounters challenges due to its reliance on password data. In password guessing research, there is a conflict between
Cheng Liu +7 more
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Learning of Structurally Unambiguous Probabilistic Grammars [PDF]
Logical Methods in Computer Science, 2023 The problem of identifying a probabilistic context free grammar has two aspects: the first is determining the grammar's topology (the rules of the grammar) and the second is estimating probabilistic weights for each rule.
Dana Fisman +2 more
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Split-Based Algorithm for Weighted Context-Free Grammar Induction
Applied Sciences, 2021 The split-based method in a weighted context-free grammar (WCFG) induction was formalised and verified on a comprehensive set of context-free languages. WCFG is learned using a novel grammatical inference method. The proposed method learns WCFG from both
Mateusz Gabor +2 more
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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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