Reduction of simple semi-conditional grammars with respect to the number of conditional productions

The present paper discusses the descriptional complexity of simple semiconditional grammars with respect to the number of conditional productions. More specifically, it demonstrates that for every phrase-structure grammar, there exists an equivalent simple semi-conditional grammar that has no more than twelve conditional productions

Simple-Semi-Conditional Versions of Matrix Grammars with a Reduced Regulating Mechanism

This paper discusses some conditional versions of matrix grammars. It establishes several characterizations of the family of the recursively enumerable languages based on these grammars. In fact, making use of the Geffert Normal forms, the present paper demonstrates these characterizations based on matrix grammars with conditions of a limited length, a reduced number of nonterminals, and a reduced number and size of matrices

Regulated Formal Models and Their Reduction

Department of Theoretical Computer Science and Mathematical LogicKatedra teoretické informatiky a matematické logikyFaculty of Mathematics and PhysicsMatematicko-fyzikální fakult