Randomized complexity of linear arrangements and polyhedra? -- Tile transition systems as structured coalgebras? -- Caesar and DNA — views on cryptology -- Automata and their interaction: Definitional suggestions -- Axiomatising asynchronous process calculi -- A polynomial time approximation scheme for dense MupIN 2S{upAT} -- Decidable classes of the verification problem in a timed predicate logic -- Interpretations of extensible objects and types -- Restrictive acceptance suffices for equivalence problems -- Grammar systems as language analyzers and recursively enumerable languages -- An interpretation of extensible objects -- Modeling operating systems schedulers with multi-stack-queue grammars -- Iterative arrays with a wee bit alternation -- Secret sharing schemes with detection of cheaters for a general access structure -- Constructive notes on uniform and locally convex spaces -- Graph automorphisms with maximal projection distances -- Kleene theorems for event-clock automata -- Strong iteration lemmata for regular, linear, context-free, and linear indexed languages -- Exponential output size of top-down tree transducers -- On recognizable languages in divisibility monoids -- Expressiveness of point-to-point versus broadcast communications -- On relative loss bounds in generalized linear regression -- Generalized P-systems -- Optimal, distributed decision-making: The case of no communication -- Generalized PCP is decidable for marked morphisms -- On time-constructible functions in one-dimensional cellular automata -- Dichotomy theorem for the generalized unique satisfiability problem -- A general categorical connection between local event structures and local traces -- Correct translation of mutually recursive function systems into TOL collage grammars -- Synchronized product of linear bounded machines -- On maximal repetitions in words -- Axiomatization of the coherence property for categories of symmetries -- Sewing grammars -- State and transition complexity of Watson-Crick finite automata -- A confluence result for a typed ?-calculus of exception handling with fixed-point -- ?-Uniformly decidable sets and turing machines -- A parallel context-free derivation hierarchy -- Generalized synchronization languages -- A generalization of Dijkstra’s calculus to typed program specifications -- Homomorphisms and concurrent term rewriting -- On two-sided infinite fixed points of morphisms -- Tiling multi-dimensional arrays -- Modeling interaction by sheaves and geometric logic -- The operators minCh and maxCh on the polynomial hierarchy -- The Kolmogorov complexity of real numbers -- A partial order method for the verification of time Petri nets -- Deriving formulas for domination numbers of fasciagraphs and rotagraphs.

This book constitutes the refereed proceedings of the 12th International Symposium on Fundamentals of Computation Theory, FCT '99, held in Iasi, Romania in August/September 1999. The 42 revised full papers presented together with four invited papers were carefully selected from a total of 102 submissions. Among the topics addressed are abstract data types, algorithms and data structures, automata and formal languages, categorical and topological approaches, complexity, computational geometry, concurrency, cryptology, distributed computing, logics in computer science, process algebras, symbolic computation, molecular computing, quantum computing, etc.