Detail publikace

Two Power-Decreasing Derivation Restrictions in Generalized Scattered Context Grammars

MASOPUST, T. MEDUNA, A. ŠIMÁČEK, J.

Originální název

Two Power-Decreasing Derivation Restrictions in Generalized Scattered Context Grammars

Anglický název

Two Power-Decreasing Derivation Restrictions in Generalized Scattered Context Grammars

Jazyk

en

Originální abstrakt

The present paper introduces and discusses generalized scattered context grammars that are based upon sequences of productions whose left-hand sides are formed by nonterminal strings, not just single nonterminals. It places two restrictions on the derivations in these grammars. More specifically, let k be a positive integer. The first restriction requires that all rewritten symbols occur within the first k symbols of the first continuous block of nonterminals in the sentential form during every derivation step. The other restriction defines derivations over sentential forms containing no more than k occurrences of nonterminals. As its main result, the paper demonstrates that both restrictions decrease the generative power of these grammars to the power of context-free grammars.

Anglický abstrakt

The present paper introduces and discusses generalized scattered context grammars that are based upon sequences of productions whose left-hand sides are formed by nonterminal strings, not just single nonterminals. It places two restrictions on the derivations in these grammars. More specifically, let k be a positive integer. The first restriction requires that all rewritten symbols occur within the first k symbols of the first continuous block of nonterminals in the sentential form during every derivation step. The other restriction defines derivations over sentential forms containing no more than k occurrences of nonterminals. As its main result, the paper demonstrates that both restrictions decrease the generative power of these grammars to the power of context-free grammars.

Dokumenty

BibTex 


@article{BUT48140,
  author="Tomáš {Masopust} and Alexandr {Meduna} and Jiří {Šimáček}",
  title="Two Power-Decreasing Derivation Restrictions in Generalized Scattered Context Grammars",
  annote="The present paper introduces and discusses generalized scattered context grammars
that are based upon sequences of productions whose left-hand sides are formed by
nonterminal strings, not just single nonterminals. It places two restrictions on
the derivations in these grammars. More specifically, let k be a positive
integer. The first restriction requires that all rewritten symbols occur within
the first k symbols of the first continuous block of nonterminals in the
sentential form during every derivation step. The other restriction defines
derivations over sentential forms containing no more than k occurrences of
nonterminals. As its main result, the paper demonstrates that both restrictions
decrease the generative power of these grammars to the power of context-free
grammars.",
  address="NEUVEDEN",
  booktitle="Acta Cybernetica",
  chapter="48140",
  edition="NEUVEDEN",
  howpublished="print",
  institution="NEUVEDEN",
  journal="Acta Cybernetica",
  number="4",
  volume="18",
  year="2008",
  month="january",
  pages="783--793",
  publisher="NEUVEDEN",
  type="journal article - other"
}