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PARALLEL CONTEXTUAL ARRAY GRAMMARS WITH TRAJECTORIES [chapter]

P. Helen Chandra, C. Martin-Vide, K. G. Subramanian, D. L. Van, P. S. P. Wang
2005 Handbook of Pattern Recognition and Computer Vision  
The method is based on contextual grammars of Marcus(1969) guided by trajectories in the generation process.The resulting grammar is called Parallel contextual array grammar with contexts shuffled on trajectories  ...  This grammar is capable of describing pictorial patterns that cannot be handled by certain other contextual array grammars introduced in the literature.  ...  Theorem 23: The emptiness problem and the finiteness problem are decidable for all classes of parallel contextual array grammars Parallel Contextual Array Grammars with contexts shuffled on Trajectories  ... 
doi:10.1142/9789812775320_0004 fatcat:pthv2crxfbaunndptrprlwh65q

Page 433 of Mathematical Reviews Vol. , Issue 87a [page]

1987 Mathematical Reviews  
Author summary: “We define a class of contextual grammars ‘in- termediate’ between the conditional contextual grammars and the contextual grammars with bounded choice (the addition of each context depends  ...  in one left-to-right or right-to-left pass with the same pass number for each derivation tree are referred to as simple multipass strategies.  ... 

Page 7285 of Mathematical Reviews Vol. , Issue 98K [page]

1998 Mathematical Reviews  
We also present the relations to contextual grammars with shuffled context and some new results on such grammars, and discuss the linguistic importance of such grammars.”  ...  {For the entire collection see MR 98i:68003.} 98k:68105 68Q50 Bruda, Stefan On the computational complexity of context-free parallel communicating grammar systems.  ... 

Extending Shape Grammars with Descriptors [chapter]

Haldane Liew
2004 Design Computing and Cognition '04  
One of the problems in using shape grammars is being able to describe succinctly and precisely the conditions necessary to perform the appropriate transformation in a drawing.  ...  The framework for the descriptors is based on the decision making process when applying a rule.  ...  Instead of relying on compound rules with parallel description grammars or using transformation and parameter restrictions, the descriptors in the contextual requirements phase rely on the visual properties  ... 
doi:10.1007/978-1-4020-2393-4_22 fatcat:fau3ynar5fcw3obrlee3mlixcu

Page 2110 of Mathematical Reviews Vol. 58, Issue 3 [page]

1979 Mathematical Reviews  
The author studies some variants of contextual grammars [cf. S. Marcus, same Rev. 14 (1969), 1525-1534; MR 41 #6636] and contextual grammars with regulated derivations.  ...  Pour ces mesures on étudie les problémes posés par J. Gruska [Information and Control 18 (1971), 502-519; MR 46 #10245}.” Paun, Gheorghe Contextual grammars with restrictions in derivation. Rev.  ... 

Page 4576 of Mathematical Reviews Vol. , Issue 98G [page]

1998 Mathematical Reviews  
Summary: “The paper deals with contextual grammars working in a totally parallel manner.  ...  98¢:68093 98g:68093 68Q50 68Q10 68Q45 Mihalache, Valeria (R-BUCHM; Bucharest) On parallel communicating grammar systems with context-free components.  ... 

Page 3884 of Mathematical Reviews Vol. , Issue 97F [page]

1997 Mathematical Reviews  
A derivation step for an external contextual grammar is, given a rule (L,u,v) of the grammar, adding a context (u,v) to a word f, obtaining thus the word ufv, provided f belongs to L.  ...  An external contextual language is a language which is the set of all words obtained from a finite set of words taken as axioms, applying repetitively derivation steps on the words obtained.  ... 

Page 4512 of Mathematical Reviews Vol. , Issue 97G [page]

1997 Mathematical Reviews  
In the paper under review, parallel variants of contextual grammars are considered.  ...  Several parallel modes of derivation are introduced and the result- ing models are compared to each other, as well as to other models defining standard families of languages, with respect to generative  ... 

On computational complexity of contextual languages

Lucian Ilie
1997 Theoretical Computer Science  
We consider the following restriction of internal contextual grammars, called local: in any derivation in a grammar, after applying a context, further contexts can be added only inside of or at most adjacent  ...  to the previous ones.  ...  In [12] , one considers internal contextual grammars with the following restriction: the words selecting the context must be maximal with respect to the subword order.  ... 
doi:10.1016/s0304-3975(96)00309-x fatcat:gmvaqtv6arfrpnw5dnazph73hm

Page 1591 of Mathematical Reviews Vol. , Issue 84d [page]

1984 Mathematical Reviews  
It is compared with the developmental languages such as OL, TOL and parallel-OL languages. We generalize AGFS by considering the effect of E and F on AGFS.  ...  Nguyen Xuan My; Paun, Gheorghe On the generative capacity of n-contextual grammars. Bull. Math. Soc. Sci. Math. R. S. Roumanie ( N.S.) 26(74) (1982), no. 4, 345-354.  ... 

Page 8286 of Mathematical Reviews Vol. , Issue 2001K [page]

2001 Mathematical Reviews  
The second part of this monograph (Chapters 10-16) is con- cerned with variants and more advanced subjects: Variants of contextual grammars (Chapter 10; one-sided contexts, determinis- tic grammars, parallel  ...  derivations, marked derivations); Two-level contextual grammars (Chapter 11); Regulated contextual gram- mars (Chapter 12; matrix, programmed and controlled contextual grammars); n-contextual grammars  ... 

Maximally Parallel Contextual String Rewriting [chapter]

Traian Florin Şerbănuţă, Liviu P. Dinu
2016 Lecture Notes in Computer Science  
parallel instance of w is computed in at most 2|w| steps Traian Florin S , erbȃnut ,ȃ (UNIBUC) Maximally Parallel Contextual String Rewriting Diaspora s , tiint ,ificȃ 2016  ...  The proposed transformations have the following properties: Properly encoding the refinement of parallel instances Erasing the extra flags and marks one obtains the rewritten word (through the current  ...  Context free grammars with maximally parallel derivation Context Sensitive L-Systems have some notion of sharing However, the context is usually altered during the rewrite P Systems [Pȃun, 1998] Multiset  ... 
doi:10.1007/978-3-319-44802-2_9 fatcat:mrcksgo75fajrongg2lebzbbay

Page 1967 of Mathematical Reviews Vol. , Issue 2001C [page]

2001 Mathematical Reviews  
grammars, m-contextual grammars, are particular cases of contextual grammars with contexts shuffled on trajectories.  ...  In this way we also obtain a very general class of contextual gram- mars such that most of the fundamental classes of contextual grammars, for instance, internal contextual grammars, external contextual  ... 

Page 7076 of Mathematical Reviews Vol. , Issue 99j [page]

1999 Mathematical Reviews  
Summary: “Bracketed contextual grammars are contextual gram- mars with an induced Dyck-structure to control the derivation process and to provide derivation trees.  ...  In this paper, we intro- duce a generalization of bracketed contextual grammars called multibracketed contextual grammars. The generative capacity of this class is investigated.  ... 

Page 8090 of Mathematical Reviews Vol. , Issue 98M [page]

1998 Mathematical Reviews  
One is based on simple partial orders of computation steps, while the other one is based on contextual nets and is an extension of a previous one for eventual CC programs.  ...  More precisely, by interpreting concurrency as possible parallelism, our semantics can be useful for a safe parallelization of some CLP computation steps.  ... 
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