STACS 93 10th Annual Symposium on Theoretical Aspects of Computer Science, Würzburg, Germany, February 25-27, 1993. Proceedings

This volume contains the proceedings of the tenth annual Symposium on Theoretical Aspects of Computer Science (STACS '93), held in W}rzburg, February 25-27, 1993. The STACS symposia are held alternately in Germany and France, and organized jointly by the Special Interest Group for Theoretical Computer Science of the Gesellschaft f}r Informatik (GI) and theSpecial Interest Group for Applied Mathematics of the Association Francaise des Sciences et Technologies de l'Information et des Syst mes (afcet). The volume includes the three invited talks which opened the three days of the symposium: "Causal and distributed semantics for concurrent processes" (I. Castellani), "Parallel architectures: design and efficient use" (B. Monien et al.), and "Transparent proofs" (L. Babai). The selection of contributed papers is organized into parts on: computational complexity, logic in computer science, efficient algorithms, parallel and distributed computation, language theory, computational geometry, automata theory, semantics and logic of programming languages, automata theory and logic, circuit complexity, omega-automata, non-classical complexity, learning theory and cryptography, and systems.

Causal and distributed semantics for concurrent processes.- Editorial note.- Alternation for two-way machines with sublogarithmic space.- Separating the lower levels of the sublogarithmic space hierarchy.- Locating P/poly optimally in the extended low hierarchy.- Measure, stochasticity, and the density of hard languages.- Halting problem of one binary Horn clause is undecidable.- Decidability and undecidability results for duration calculus.- Defining ?-typed ?-calculi by axiomatizing the typing relation.- The complexity of logic-based abduction.- Treewidth of chordal bipartite graphs.- On paths in networks with valves.- Scheduling interval ordered tasks in parallel.- An O(?n)-worst-case-time solution to the granularity problem.- The synthesis problem of Petri nets.- General refinement and recursion operators for the Petri Box calculus.- On fairness in distributed automated deduction.- Divide-and-conquer algorithms on the hypercube.- A first-order isomorphism theorem.- Splittings, robustness and structure of complete sets.- Defying upward and downward separation.- Counting, selecting, and sorting by query-bounded machines.- Cancellation in context-free languages: Enrichment by reduction.- Counting overlap-free binary words.- The limit set of recognizable substitution systems.- Partially commutative Lyndon words.- Parallel architectures: Design and efficient use.- Weighted closest pairs.- Rectilinear path queries in a simple rectilinear polygon.- Parallel algorithm for the matrix chain product and the optimal triangulation problems (extended abstract).- Multi-list ranking: complexity and applications.- Exact algorithms for a geometric packing problem (extended abstract).- A decomposition theorem for probabilistic transition systems.- Local automata and completion.-Efficient compression of wavelet coefficients for smooth and fractal-like data.- On the equivalence of two-way pushdown automata and counter machines over bounded languages.- Computability properties of low-dimensional dynamical systems.- Fixed-parameter intractability II (extended abstract).- Limits on the power of parallel random access machines with weak forms of write conflict resolution.- On using oracles that compute values.- Multicounter automata with sublogarithmic reversal bounds.- Structured operational semantics for concurrency and hierarchy.- The complexity of verifying functional programs.- Towards the formal design of self-stabilizing distributed algorithms.- Axiomatizations of temporal logics on trace systems.- Capabilities and complexity of computations with integer division.- Extended locally definable acceptance types.- Gap-definability as a closure property.- On the logical definability of some rational trace languages.- Solving systems of set constraints using tree automata.- Complement problems and tree automata in AC-like theories (extended abstract).- Transparent (holographic) proofs.- Computing symmetric functions with AND/OR circuits and a single MAJORITY gate.- Threshold circuits for iterated multiplication: Using AC0 for free.- Circuits with monoidal gates.- A non-probabilistic switching lemma for the Sipser function.- Frontiers of feasible and probabilistic feasible Boolean manipulation with branching programs.- On syntactic congruences for ?—languages.- A polynomial time algorithm for the equivalence of two morphisms on ?-regular languages.- Locally threshold testable languages of infinite words.- Deterministic asynchronous automata for infinite traces.- Recursive automata on infinite words.- A complexity theoretic approach toincremental computation.- Precise average case complexity.- The bit probe complexity measure revisited.- Language learning with some negative information.- Language learning with a bounded number of mind changes.- Efficient sharing of many secrets.- The KIV system a tool for formal program development.- 1st Grade — A system for implementation, testing and animation of graph algorithms.- The program verifier Tatzelwurm.- LEDA a library of efficient data types and algorithms.- Defining ?-typed ?-calculi by axiomatizing the typing relation.