Accession Number : AD0666408

Title :   CLOSURES WHICH PRESERVE FINITENESS IN FAMILIES OF LANGUAGES,

Corporate Author : SYSTEM DEVELOPMENT CORP SANTA MONICA CALIF

Personal Author(s) : Rose,Gene F.

Report Date : 01 OCT 1967

Pagination or Media Count : 35

Abstract : Each set of operations selected from union, intersection, complement, star, quotients, derivatives, word-reversal and homomorphisms is investigated with respect to its closure of an arbitrary family of word-sets, as well as to its closure of an arbitrary family of regular languages. Certain sets are shown to produce a finite closure only for every finite family of regular languages; in either case, the closure for a given family of regular languages can be calculated by algorithm. For a third class of sets, the closure is not necessarily finite even for finite families of regular languages. (Author)

Descriptors :   (*LANGUAGE, SET THEORY), VOCABULARY, ALGORITHMS, LINGUISTICS

Subject Categories : Linguistics

Distribution Statement : APPROVED FOR PUBLIC RELEASE