Filters








410 Hits in 5.2 sec

The Church-Rosser languages are the deterministic variants of the growing context-sensitive languages

Gundula Niemann, Friedrich Otto
2005 Information and Computation  
characterization of the growing context-sensitive languages and the Church-Rosser languages, respectively.  ...  The growing context-sensitive languages have been classified through the shrinking two-pushdown automaton, the deterministic version of which characterizes the class of generalized Church-Rosser languages  ...  Thus, the class GCRL of generalized Church-Rosser languages coincides with the class of 'deterministic growing context-sensitive languages.'  ... 
doi:10.1016/j.ic.2004.09.003 fatcat:t4f3hgckcjcnxj64dns2mjzoji

The Church-Rosser languages are the deterministic variants of the growing context-sensitive languages [chapter]

Gundula Niemann, Friedrich Otto
1998 Lecture Notes in Computer Science  
characterization of the growing context-sensitive languages and the Church-Rosser languages, respectively.  ...  The growing context-sensitive languages have been classified through the shrinking two-pushdown automaton, the deterministic version of which characterizes the class of generalized Church-Rosser languages  ...  Thus, the class GCRL of generalized Church-Rosser languages coincides with the class of 'deterministic growing context-sensitive languages.'  ... 
doi:10.1007/bfb0053554 fatcat:wuip36fa7vgnzl6rbki7pacdle

Page 1272 of Mathematical Reviews Vol. , Issue 99b [page]

1991 Mathematical Reviews  
Heinrich Seidel (Dresden) 99b:68112 68Q45 03D05 68Q42 68Q68 Buntrock, Gerhard; Otto, Friedrich (D-KSSL-MI; Kassel) Growing context-sensitive languages and Church-Rosser languages.  ...  In addition the authors show: (i) the family of (generalized) Church-Rosser languages and the family of context-free languages are incomparable, and (ii) each GCS language is accepted in polynomial time  ... 

Page 4866 of Mathematical Reviews Vol. , Issue 2004f [page]

2004 Mathematical Reviews  
the class of Church-Rosser languages can be interpreted as the deterministic counterpart to the class of growing context-sensitive languages.  ...  It is shown that each Church-Rosser language can be specified by a context-splittable Church-Rosser language system.  ... 

Page 6990 of Mathematical Reviews Vol. , Issue 96k [page]

1996 Mathematical Reviews  
The proof is given by means of Post’s correspondence problem.” 96k:68111 68Q45 Buntrock, Gerhard (D-WRZB-I; Wiirzburg); Otto, Friedrich (D-KSSL-MI; Kassel) Growing context-sensitive languages and Church-Rosser  ...  As a consequence the class of (generalized) Church-Rosser languages and the class of context-free languages are incomparable under set inclusion, which verifies a conjecture of R. McNaughton, P.  ... 

The size of Higman–Haines sets

Hermann Gruber, Markus Holzer, Martin Kutrib
2007 Theoretical Computer Science  
We show that for the family of Church-Rosser languages the Higman-Haines sets, which are the sets of all scattered subwords of a given language and the sets of all words that contain some word of a given  ...  The non-effectiveness is based on a non-recursive tradeoff result between the language description mechanism of Church-Rosser languages and the corresponding Higman-Haines sets, which in turn is also valid  ...  Conclusions We have investigated the size of Higman-Haines sets for the language families of recursively enumerable, recursive, context-sensitive, growing context-sensitive, and Church-Rosser languages  ... 
doi:10.1016/j.tcs.2007.07.036 fatcat:pj5zmp5dfvhuvjridivq7l4zia

Page 4945 of Mathematical Reviews Vol. , Issue 99g [page]

1999 Mathematical Reviews  
Summary: “The growing context-sensitive languages have been classified through the shrinking two-pushdown automaton, the deterministic version of which characterizes the class of general- ized Church-Rosser  ...  context-sensitive languages.  ... 

Page 2059 of Mathematical Reviews Vol. , Issue 2003C [page]

2003 Mathematical Reviews  
The main results: (1) The class of Church-Rosser languages co- incides with the class of languages accepted by a special type of deterministic restarting automata with rewriting. (2) Any growing context-sensitive  ...  language is recognized by a restarting automa- ton with rewriting. (3) The class of Church-Rosser congruential languages is a quotient basis for the recursively enumerable lan- guages.  ... 

An Insertion into the Chomsky Hierarchy? [chapter]

Robert McNaughton
1999 Jewels are Forever  
One important result is that the deterministic growing context-sensitive languages turn out to be identical to an interesting family of formal languages de nable in a certain way by con uent reduction  ...  These discoveries have pointed out certain break-throughs connected with the concept of growing contextsensitive languages, which originated in the 1980's with a paper by E. Dahlhaus and M.K.  ...  Growing context-sensitive languages.  ... 
doi:10.1007/978-3-642-60207-8_18 fatcat:ap2y32u3azgtxf3uarecwh5yke

Page 5983 of Mathematical Reviews Vol. , Issue 94j [page]

1994 Mathematical Reviews  
Summary: “We investigate growing context-sensitive grammars (GCSGs). The variable membership problem for GCSGs is shown to be NP-complete. This solves a problem posed by E. Dahlhaus and M. K.  ...  The first group con- tains four papers on questions in term rewriting which have been stimulated by research in graph rewriting: type assignment, con- fluence, Church-Rosser properties and reduction strategies  ... 

Regular Languages Are Church-Rosser Congruential [chapter]

Volker Diekert, Manfred Kufleitner, Klaus Reinhardt, Tobias Walter
2012 Lecture Notes in Computer Science  
In [Niemann and Otto 2005] Church-Rosser languages were characterized as deterministic growing context-sensitive languages. For more results about Church-Rosser languages see e.g.  ...  Since {a m b n | m ≥ n} is deterministic context-free, the class of Church-Rosser languages is strictly larger than the class of Church-Rosser congruential languages.  ...  The languages L 1 and L 2 are non-regular but deterministic context-free whereas L 3 is regular. The first language L 1 is Church-Rosser congruential.  ... 
doi:10.1007/978-3-642-31585-5_19 fatcat:42x3d3j6h5gy7ojsei7jbogqju

Left-to-right regular languages and two-way restarting automata

Friedrich Otto
2009 RAIRO - Theoretical Informatics and Applications  
The intersection of the classes CRL and CFL has been investigated only recently [13] , and it has been shown that the problem of deciding whether a given Church-Rosser or context-free language belongs  ...  Further, deterministic RWW-automata accept the Church-Rosser languages (CRL) of [15, 19] , which are of interest as they have linear-time decidable membership problems.  ...  Also he thanks Hartmut Messerschmidt from Universität Kassel for fruitful discussions on the results presented here and their proofs.  ... 
doi:10.1051/ita/2009013 fatcat:pghe46jrpvbgzcwdcfxuuuzzsu

The degree of word-expansion of lexicalized RRWW-automata — A new measure for the degree of nondeterminism of (context-free) languages

F. Mráz, F. Otto, M. Plátek
2009 Theoretical Computer Science  
Our main results establish a hierarchy of classes of context-free languages and two hierarchies of classes of non-context-free languages that are based on the expansion factor of a language.  ...  This type of recognition is typical for analysis by reduction, a method used in linguistics for the creation and verification of formal descriptions of natural languages.  ...  As M is a deterministic RRWW-automaton, L C (M) is a Church-Rosser language, which implies that it belongs to the class GCSL of growing context-sensitive languages [3] .  ... 
doi:10.1016/j.tcs.2009.03.017 fatcat:e4wmz6ptkvefznvrqt52djqxie

Infinite Convergent String-rewriting Systems and Cross-sections for Finitely Presented Monoids

F. OTTO, M. KATSURA, Y. KOBAYASHI
1998 Journal of symbolic computation  
On the other hand, it is shown that each finitely presented monoid with a decidable word problem has a finite presentation that admits a cross-section which is a Church-Rosser language.  ...  However, regular cross-sections or even context-free cross-sections do not suffice.  ...  By admitting weight-reducing string-rewriting systems we obtain the class of generalized Church-Rosser languages (GCRL), which can be interpreted as the class of deterministic growing context-sensitive  ... 
doi:10.1006/jsco.1998.0230 fatcat:66f3r5ntwvdz5p6extzc7wlt3e

The context-splittable normal form for Church–Rosser language systems

Jens R. Woinowski
2003 Information and Computation  
In this paper the context-splittable normal form for rewriting systems defining Church-Rosser languages is introduced.  ...  It is proved that this normal form can be achieved for each Church-Rosser language and that the construction is effective. Some interesting consequences of this characterization are given, too.  ...  Church-Rosser languages Definition 1.  ... 
doi:10.1016/s0890-5401(03)00035-x fatcat:oanqinzkyverndyopx4o4gxqgm
« Previous Showing results 1 — 15 out of 410 results