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Page 4575 of Mathematical Reviews Vol. , Issue 98G [page]

1998 Mathematical Reviews  
When no control is imposed on the splicing operation, we get a charac- terization of regular languages. When a control is considered, we obtain characterizations of recursively enumerable languages.  ...  For example, for each recursively enumerable string language L there exists a quasi-monotonic one-dimensional array grammar generating the array image of L.”  ... 

Page 2769 of Mathematical Reviews Vol. , Issue 99d [page]

1991 Mathematical Reviews  
) Characterizations of recursively enumerable languages by means of insertion grammars.  ...  We prove here that each recursively enumerable language can be written as the weak coding of the image by an inverse morphism of a language generated by an insertion grammar (with the maximal length of  ... 

On the weight of universal insertion grammars

Lila Kari, Petr Sosík
2008 Theoretical Computer Science  
We study the computational power of pure insertion grammars. We show that pure insertion grammars of weight 3 can characterize all recursively enumerable languages.  ...  This is achieved by either applying an inverse morphism and a weak coding, or a left (right) quotient with a regular language.  ...  Acknowledgements This research was supported by the Canada Research Chair Grant and NSERC Discovery Grant to L.K., and by the Ramón y Cajal Program and the Czech Science Foundation, grant No. 201/06/0567  ... 
doi:10.1016/j.tcs.2008.01.037 fatcat:wywk2xjtm5apnif6lvbdhck5tm

Page 1968 of Mathematical Reviews Vol. , Issue 2001C [page]

2001 Mathematical Reviews  
; Yu, Sheng (3-WON-C; London, ON) At the crossroads of DNA computing and formal languages: characterizing recursively enumerable languages using insertion-deletion systems.  ...  Summary: “Several characterizations of recursively enumerable (RE) languages are presented, using insertion-deletion systems.  ... 

Context-free insertion–deletion systems

Maurice Margenstern, Gheorghe Păun, Yurii Rogozhin, Sergey Verlan
2005 Theoretical Computer Science  
Rather unexpectedly, we found that context-free insertion-deletion systems characterize the recursively enumerable languages.  ...  that membrane systems with one membrane having contextfree insertion-deletion rules without conditional use of them generate all recursively enumerable languages (this improves an earlier result).  ...  InsDel systems of a "sufficiently large" weight can characterize RE, the family of recursively enumerable languages.  ... 
doi:10.1016/j.tcs.2004.06.031 fatcat:n52nnfcke5b2zpbr4im4roqd4a

Characterizations of recursively enumerable languages by means of insertion grammars

Carlos Martin-Vide, Gheorghe Păun, Arto Salomaa
1998 Theoretical Computer Science  
We prove here that each recursively enumerable language can be written as the weak coding of the image by an inverse morphism of a language generated by an insertion grammar (with the maximal length of  ...  An insertion grammar is based on pure rules of the form uu + lc~v (the string x is inserted in the context (u,u)).  ...  We also denote by FIN, REG, LIN, CF, CS, RE the families of finite, regular, linear, context-free, contextsensitive, recursively enumerable languages, respectively.  ... 
doi:10.1016/s0304-3975(97)00079-0 fatcat:5bngvgfwpzagxm5rqqbdrhoqbm

Homomorphic characterizations of recursively enumerable languages with very small language classes

Satoshi Okawa, Sadaki Hirose
2001 Theoretical Computer Science  
In this paper, we attempt to characterize the class of recursively enumerable languages with much smaller language classes than that of linear languages.  ...  Then the homomorphic characterizations of the class of recursively enumerable languages are obtained using these classes and a class, ML, of minimal linear languages.  ...  Acknowledgements The authors would like to thank a referee who gave valuable comments to improve the paper and informed a recent result on this theme.  ... 
doi:10.1016/s0304-3975(99)00110-3 fatcat:35lcfshvgzfmdhq47ycrorva4y

On a homomorphic characterization of recursively enumerable languages

Arto Salomaa
1973 Annales Academiae Scientiarum Fennicae Series A I Mathematica  
It does not seem likely that the construction could be modifred to leld a locally testable language. Mathematics Department I-Iniyersitv of 'Iurku. Finland  ...  So far our definitions &re based on the alphabet V7 alone. We now consider an arbitrary but fixed recursively enumerable language L over Vr, generated by a type 0 grammar G : (VN, Vr, au+t, l).  ...  Proot of Theorem 1 Every recursivell' enumerable language over V,7 is generated by a tgle 0 grammar.  ... 
doi:10.5186/aasfm.1973.525 fatcat:yw7q5jr3lrf55cfovtgnb4gqkm

Page 3304 of Mathematical Reviews Vol. , Issue 2004d [page]

2004 Mathematical Reviews  
enumerable languages with insertion grammars.  ...  Summary: “In this note we obtain some representation theorems for recursively enumerable languages by using insertion systems and morphisms.  ... 

Page 10266 of Mathematical Reviews Vol. , Issue 2004m [page]

2004 Mathematical Reviews  
, ON) Representing recursively enumerable languages by iterated deletion.  ...  Summary: “A characterization of the recursively enumerable lan- guages in terms of the iterated deletion operation is given. This solves two open problems posed by M. Ito and P. V.  ... 

Canonical scattered context generators of sentences with their parses

Alexander Meduna, Jiří Techet
2007 Theoretical Computer Science  
It demonstrates that for every recursively enumerable language, L, there exists a canonical scattered context generator whose language consists of L's sentences followed by their parses.  ...  In fact, this result is established based on the generators containing no more than six nonterminals.  ...  The first author was supported by GAČR grant 201/07/0005 and research intent MSM 021630528. The second author was supported by GAČR grant 102/05/H050 and FRVŠ grant FR762/2007/G1.  ... 
doi:10.1016/j.tcs.2007.07.044 fatcat:ru775vcgtjgehm3k3nai7qfxae

Page 8089 of Mathematical Reviews Vol. , Issue 98M [page]

1998 Mathematical Reviews  
We first prove several variants of this charac- terization of recursively enumerable languages.  ...  Summary: “We investigate the problem of expressing an arbitrary recursively enumerable language Ly in terms of an internal con- textual language.  ... 

MORPHIC CHARACTERIZATIONS OF LANGUAGE FAMILIES IN TERMS OF INSERTION SYSTEMS AND STAR LANGUAGES

FUMIYA OKUBO, TAKASHI YOKOMORI
2011 International Journal of Foundations of Computer Science  
A similar characterization can be obtained for recursively enumerable languages, where insertion systems of weight (3, 3) and 2-star languages are involved.  ...  This paper will mainly focus on those systems whose insertion operations are performed in a context-free fashion, called context-free insertion systems, and obtain several characterizations of language  ...  Further, we shall show that a manner of construction used in the proof can be applied to characterize recursively enumerable languages in a similar form of h(L(γ) ∩ F + ), for some insertion system γ and  ... 
doi:10.1142/s012905411100799x fatcat:6gyge2dnnrhu3jfm3fmgz32g54

Morphic characterizations of languages in Chomsky hierarchy with insertion and locality

Kaoru Fujioka
2011 Information and Computation  
This paper concerns new characterizations of regular, context-free, and recursively enumerable languages, using insertion systems with lower complexity.  ...  Specifically, each recursively enumerable language L can be represented in the form L = h(L(γ ) ∩ R), where γ is an insertion system of weight (3, 3) , R is a strictly 2-testable language, and h is a projection  ...  It has been shown that by using insertion and deletion operations, any recursively enumerable language can be obtained in [2, 8] .  ... 
doi:10.1016/j.ic.2010.11.011 fatcat:d46gkl4rwzg45due2d4rkqkqru

Page 4274 of Mathematical Reviews Vol. , Issue 95g [page]

1995 Mathematical Reviews  
(R-BRAS; Brasov) On the characterization of some generative grammars by numerical functions.  ...  The main problem presented in this paper is the learnability of enumerable families of uniformly recursive languages in terms of the number of allowed mind changes.  ... 
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