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On the closure properties of linear conjunctive languages

Alexander Okhotin
2003 Theoretical Computer Science  
In this paper we investigate the closure properties of the language family generated by linear conjunctive grammars; the main result is its closure under complement, which implies that it is closed under  ...  We also consider several cases in which the concatenation of two linear conjunctive languages is certain to be linear conjunctive.  ...  Acknowledgements I am grateful to Kai Salomaa for his valuable advices on di erent versions of this paper. I would also like to thank my anonymous referee for important comments and suggestions.  ... 
doi:10.1016/s0304-3975(02)00543-1 fatcat:j52rv3xahrg4rpqrs3xl3amwri

AN OVERVIEW OF CONJUNCTIVE GRAMMARS [chapter]

ALEXANDER OKHOTIN
2004 Current Trends in Theoretical Computer Science  
Several theoretical results on their properties have been obtained since then, and a number of efficient parsing algorithms that justify the practical value of the concept have been developed.  ...  Conjunctive grammars were introduced in 2000 as a generalization of context-free grammars that allows the use of an explicit intersection operation in rules.  ...  Closure properties of conjunctive grammars are partially known.  ... 
doi:10.1142/9789812562494_0064 fatcat:ukdx344tsvgivnvgpu75sqw42u

Expressive power of LL(k) Boolean grammars

Alexander Okhotin
2011 Theoretical Computer Science  
It is also shown that linear conjunctive LL grammars cannot generate any language of the form L · {a, b}, with L non-regular, and that no languages of the form L · c * , with non-regular L, can be generated  ...  These results are used to establish a detailed hierarchy and closure properties of these and related families of formal languages.  ...  The work was supported by the Academy of Finland under grants 118540 and 134860.  ... 
doi:10.1016/j.tcs.2011.05.013 fatcat:mw3g3rip4zferecbwacbfrijou

Page 1400 of Mathematical Reviews Vol. , Issue 2004b [page]

2004 Mathematical Reviews  
Kingston, ON) On the closure properties of linear conjunctive languages.  ...  In the paper, the closure properties of the language family gen- erated by linear conjunctive grammars are investigated. The key result is that the family is closed under complement.  ... 

On the equivalence of linear conjunctive grammars and trellis automata

Alexander Okhotin
2004 RAIRO - Theoretical Informatics and Applications  
Trellis automata, also studied under the name of one-way real-time cellular automata, have been known since early 1980s as a purely abstract model of parallel computers, while linear conjunctive grammars  ...  for the importance of the language family they all generate.  ...  I am grateful to Sheng Yu for pointing me to the concept of trellis automaton and to Kai Salomaa for inspiring discussions on the subject of this paper, as well as for his detailed comments on its numerous  ... 
doi:10.1051/ita:2004004 fatcat:p3ypdctlfrfv3adjg564dh2q7e

A lattice-theoretic characterization of safety and liveness

Panagiotis Manolios, Richard Trefler
2003 Proceedings of the twenty-second annual symposium on Principles of distributed computing - PODC '03  
In a well-known paper Alpern and Schneider gave a topological characterization of safety and liveness for the linear time framework.  ...  We present a latticetheoretic characterization that allows us to unify previous results on safety and liveness, including the results for the linear time and branching time frameworks and for ω-regular  ...  L(B) = {t ∈ Σ ω | there is an accepting run of B on t} is the language of B.  ... 
doi:10.1145/872035.872083 dblp:conf/podc/ManoliosT03 fatcat:u6gzeonslbf35pfw5xd4q5xvam

Conjunctive and Boolean grammars: The true general case of the context-free grammars

Alexander Okhotin
2013 Computer Science Review  
The intended readership includes any computer scientists looking for a compact and accessible description of this formal model and its properties, as well as for a general outlook on formal grammars.  ...  Conjunctive grammars extend the definition of a context-free grammar by allowing a conjunction operation in the rules; Boolean grammars are further equipped with an explicit negation.  ...  This section summarizes the known closure properties of the five language families surveyed in this paper: those generated by linear conjunctive grammars (LinConj), conjunctive grammars (Conj), Boolean  ... 
doi:10.1016/j.cosrev.2013.06.001 fatcat:vjrnokycqres5mfpdupksfaumm

Closures and Modules Within Linear Logic Concurrent Constraint Programming [chapter]

Rémy Haemmerlé, François Fages, Sylvain Soliman
2007 Lecture Notes in Computer Science  
There are two somewhat contradictory ways of looking at modules in a given programming language. On the one hand, module systems are largely independent of the particulars of programming languages.  ...  On the other hand, the module constructs may interfere with the programming constructs, and may be redundant with the other scope mechanisms of a specific programming language, such as closures for instance  ...  These results have been illustrated with an instantiation of the MLCC scheme to constraint logic programs, leading to a simple yet powerful module system similar to the one proposed in [10] , supporting  ... 
doi:10.1007/978-3-540-77050-3_45 fatcat:eeuecetzpjdzdm7cdsdfy5jabq

Intuitionistic LTL and a New Characterization of Safety and Liveness [chapter]

Patrick Maier
2004 Lecture Notes in Computer Science  
Frequently, we will refer to the elements of this lattice as languages or properties.  ...  In particular, ILTL admits an elegant logical characterization of safety and liveness properties. Keywords Linear-time temporal logic, intuitionistic logic, safety and liveness properties.  ...  Acknowledgements The author thanks Viorica Sofronie-Stokkermans for the many intensive discussions that greatly helped to develop and clarify the ideas of this report.  ... 
doi:10.1007/978-3-540-30124-0_24 fatcat:hyxxymr6yvdmrgphbzlbezmkbq

Design of abstract domains using first-order logic

Elena Marchiori
1999 Theoretical Computer Science  
Moreover, the choice of the assertion language allows one to focus only on the abstract domains that describe the properties of interest, that is, those expressible in that language.  ...  An assertion language is chosen that specifies the properties of interest, and abstract domains on that assertion language are defined to be suitably chosen sets of assertions.  ...  Acknowledgements Many thanks to the anonymous referees: both the contents and the presentation of the paper have improved a lot thanks to their comments and suggestions. A special word  ... 
doi:10.1016/s0304-3975(98)00231-x fatcat:yrkpiatasnesdasvddqzojvw6m

Conjunctive grammars and alternating pushdown automata

Tamar Aizikowitz, Michael Kaminski
2013 Acta Informatica  
In this paper we explore several extensions of models for context-free languages which combine both the notion of conjunction and of disjunction, leading to a richer set of languages.  ...  In this paper we introduce a variant of alternating pushdown automata, Synchronized Alternating Pushdown Automata, which accept the same class of languages as those generated by conjunctive grammars.  ...  Acknowledgments The authors are grateful to Nissim Francez for his remarks on the first draft of this paper.  ... 
doi:10.1007/s00236-013-0177-3 fatcat:zt4wycctujhujonkrsm6bxtnsu

Conjunctive Grammars and Alternating Pushdown Automata [chapter]

Tamar Aizikowitz, Michael Kaminski
2008 Lecture Notes in Computer Science  
In this paper we explore several extensions of models for context-free languages which combine both the notion of conjunction and of disjunction, leading to a richer set of languages.  ...  In this paper we introduce a variant of alternating pushdown automata, Synchronized Alternating Pushdown Automata, which accept the same class of languages as those generated by conjunctive grammars.  ...  Acknowledgments The authors are grateful to Nissim Francez for his remarks on the first draft of this paper.  ... 
doi:10.1007/978-3-540-69937-8_6 fatcat:mqxb5ztnxzbpvbcxwkqh2flnhq

Whale Calf, a Parser Generator for Conjunctive Grammars [chapter]

Alexander Okhotin
2003 Lecture Notes in Computer Science  
Whale Calf is a parser generator that supports the conjunctive grammars, introduced in [2, 3, 4], as the means of specifying the language.  ...  Conjunctive grammars inherit all descriptive capabilities of context-free grammars (since every context-free grammar is a conjunctive grammar) and give an opportunity to use an explicit language intersection  ...  The preliminary results on the properties of this language family [10] have not yet been published.  ... 
doi:10.1007/3-540-44977-9_20 fatcat:2s37fkhs4nahrdsz5y7fmatyzi

A brief note about Rott contraction

E. Ferme RO Rodriguez
1998 Logic Journal of the IGPL  
One of the ways to model contraction functions for belief sets is epistemic entrenchment.  ...  The first step was provided by Gärdenfors in [5] , who defined epistemic entrenchment and a contraction function in terms of it and related the latter with the AGM contraction function.  ...  A theory is understood to be any set K of proposition closed under Cn, i.e. such that Cn(K) = K. Let L be the set of all the sentences of the language. Let K the set of all theories of the language.  ... 
doi:10.1093/jigpal/6.6.835 fatcat:plh4xqitazhqxgsyhwub7agava

Locally finite languages

Olivier Finkel
2001 Theoretical Computer Science  
Then we study closure properties of the family LOC of locally ÿnite languages, and show that most undecidability results that hold for context free languages may be extended to locally ÿnite languages.  ...  This result, combined with a preceding one of (Finkel and Ressayre (J.  ...  Then remark that if one substitute in the language L Aut the language L n−1 (q i ; q j ; E) for the letter (q i ; q j ; E), we obtain the ! n -language L ! n (Aut).  ... 
doi:10.1016/s0304-3975(99)00286-8 fatcat:x43nxdrzzzfafaoykf4dwbabrm
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