Left-forbidding cooperating distributed grammar systems

0346740 - MÚ 2011 RIV NL eng J - Journal Article
Goldefus, F. - Masopust, Tomáš - Meduna, A.
Left-forbidding cooperating distributed grammar systems.
Theoretical Computer Science. Roč. 411, 40-42 (2010), s. 3661-3667. ISSN 0304-3975. E-ISSN 1879-2294
Institutional research plan: CEZ:AV0Z10190503
Keywords : cooperating distributed grammar system * cooperating derivation mode * left-forbidding grammar * generative power * descriptional complexity
Subject RIV: BA - General Mathematics
Impact factor: 0.838, year: 2010
http://www.sciencedirect.com/science/article/pii/S0304397510003440

A left-forbidding grammar, introduced in this paper, is a context-free grammar, where a set of nonterminal symbols is attached to each context-free production. Such a production can rewrite a nonterminal provided that no symbol from the attached set occurs to the left of the rewritten nonterminal in the current sentential form. The present paper discusses cooperating distributed grammar systems with left-forbidding grammars as components and gives some new characterizations of language families of the Chomsky hierarchy. In addition, it also proves that twelve nonterminals are enough for cooperating distributed grammar systems working in the terminal derivation mode with two left-forbidding components (including erasing productions) to characterize the family of recursively enumerable languages.
Permanent Link: http://hdl.handle.net/11104/0187681