Fundamentals of Computation Theory

This volume contains the proceedings of the Ninth Conference on Fundamentalsof Computation Theory (FCT 93) held in Szeged, Hungary, in August 1993. The conference was devoted to a broad range of topics including: - Semanticsand logical concepts in the theory of computing and formal specification - Automata and formal languages - Computational geometry, algorithmic aspects of algebra and algebraic geometry, cryptography - Complexity (sequential, parallel, distributed computing, structure, lower bounds, complexity of analytical problems, general concepts) - Algorithms (efficient, probabilistic, parallel, sequential, distributed) - Counting and combinatorics in connection with mathematical computer science The volume contains the texts of 8 invitedlectures and 32 short communications selected by the international program committee from a large number of submitted papers.

Inhalt
Rewriting, möbius functions and semi-commutations.- Simulations between different models of parallel computers.- Dense and disjunctive properties of languages.- The hierarchy of codes.- Five facets of hyperedge replacement beyond context-freeness.- An action structure for synchronous ?-calculus.- AC0 circuit complexity.- Pattern languages: Problems of decidability and generation.- General solution of mirror equation.- Decidability of equivalence for linear letter to letter top-down tree transducers.- Translations between flowchart schemes and process graphs.- Local equational logic.- Liveness of weighted circuits and the diophantine problem of Frobenius.- Context-free graph grammars: Separating vertex replacement from hyperedge replacement.- Formal languages consisting of primitive words.- Undecidability of the surjectivity problem for 2D cellular automata: A simplified proof.- Efficient interpretation of state charts.- Implementation of a universal unification algorithm for macro tree transducers.- Finding maximum convex polygons.- Approximations with axis-aligned rectangles (extended abstract).- Vector sequence analysis and full weak safety for concurrent systems.- Does transitivity help? On the complexity of poset properties.- Generalized topological sorting in linear time.- Easily checked self-reducibility.- On the complexities of linear LL(1) and LR(1) grammars.- On the relation between firing sequences and processes of Petri nets.- Maximum covering with D cliques.- Monotonically labelled ordered trees and multidimensional binary trees.- A maximum path length pumping lemma for edge-replacement languages.- Regular approximations to shuffle products of context-free languages, and convergence of their generating functions.- The equational theory of a Boolean monad.-Non erasing Taring machines: a frontier between a decidable halting problem and Universality.- On scattered syntactic monoids.- Regular tree languages without unary symbols are star-free.- One-way cellular automata on cayley graphs.- ON tree pattern unification problems.- Structural Equivalence and ETOL grammars.- A hierarchy of deterministic top-down tree transformations.- Synthesis of O(lg n) testable trees.- On the learnability of a restricted predicate formulae.