Přístupnostní navigace
E-application
Search Search Close
Publication detail
MEDUNA, A. ZEMEK, P.
Original Title
Controlled Pure Grammar Systems
Type
journal article in Web of Science
Language
English
Original Abstract
This paper discusses grammar systems that have only terminals, work in the leftmost way, and generate their languages under the regulation by control languages over rule labels. It establishes three results concerning their generative power. First, without any control languages, these systems are not even able to generate all context-free languages. Second, with regular control languages, these systems, having no more than two components, characterize the family of recursively enumerable languages. Finally, with control languages that are themselves generated by regular-controlled context-free grammars, these systems over unary alphabets generate nothing but regular languages. In its introductory section, the paper gives a motivation for introducing these systems, and in the concluding section, it formulates several open problems.
Keywords
formal languages, pure grammar systems, controlled derivations
Authors
MEDUNA, A.; ZEMEK, P.
RIV year
2012
Released
28. 10. 2012
ISBN
0948-6968
Periodical
Journal of Universal Computer Science
Year of study
18
Number
14
State
Republic of Austria
Pages from
2024
Pages to
2040
Pages count
17
URL
http://www.jucs.org/jucs_18_14/controlled_pure_grammar_systems
BibTex
@article{BUT96924, author="Alexandr {Meduna} and Petr {Zemek}", title="Controlled Pure Grammar Systems", journal="Journal of Universal Computer Science", year="2012", volume="18", number="14", pages="2024--2040", issn="0948-6968", url="http://www.jucs.org/jucs_18_14/controlled_pure_grammar_systems" }