STACS 87 4th Annual Symposium on Theoretical Aspects of Computer Science, Passau, FRG, February 19-21, 1987

Towards a theory of relativizations: Positive relativizations.- Natural semantics.- On local routing of two-terminal nets.- Geometric relations among Voronoi diagrams.- Finding the largest empty rectangle on a grated surface.- Efficient graph algorithms using limited communication on a fixed-size array of processors.- On selecting the largest element in spite of erroneous information.- The correlation between the complexities of the non-hierarchical and hierarchical versions of graph problems.- Graph isomorphism is in the low hierarchy.- A hierarchy theorem for almost everywhere complex sets with application to polynomial complexity degrees.- Self-reducibility.- Probability one separation of the Boolean hierarchy.- Reversal complexity of multicounter and multihead machines.- Computing the counting function of context-free languages.- On the k-freeness of morphisms on free monoids.- Avoidable patterns on 2 letters.- Polynomial operations on rational languages.- Some structural aspects of hypergraph languages generated by hyperedge replacement.- Specification and implementation of concurrently accessed data structures: An abstract data type approach.- On implementations of loose abstract data type specifications and their vertical composition.- Are homomorphisms sufficient for behavioural implementations of deterministic and nondeterministic data types'.- Some remarks on presentations by finite Church-Rosser Thue systems.- Ground term confluence in parametric conditional equational specifications.- Describing semantic domains with sprouts.- Comparing direct and continuation semantics styles for concurrent languages.- Expressibility of first order logic with a nondeterministic inductive operator.- Bounded nondeterminism and the approximation induction principle in process algebra.- The step failure semantics.- On the complexity of containment, equivalence, and reachability for finite and 2-dimensional vector addition systems with states.- Closure properties of deterministic Petri nets.- Some results on fairness: The regular case.- Decidability questions for fairness in Petri nets.- Optimal sorting on multi-dimensionally mesh-connected computers.- On the contact-minimization-problem.- Making distributed spanning tree algorithms fault-resilient.- The derivation of on-the-fly garbage collection algorithms from distributed termination detection protocols.- On the expected complexity of distributed selection.- LPG: A generic, logic and functional programming language.- CEC.- ASSPEGIQUE.- REVEUR4 : A laboratory for conditional rewriting.- An interactive, incremental and portable computer algebra system for ?-calculus and combinatory logic based on video edition and rewriting techniques.- The Passau RAP System: Rapid prototyping for algebraic specifications.- SPRAC: A software engineering environment.- SLOG: A logic interpreter for equational clauses.- An algebraic transformation system for occam programs.- REVE a rewrite rule laboratory.