Showing papers in "Theoretical Computer Science in 2002"

TL;DR: A step towards a theory on Evolutionary Algorithms, in particular, the so-called (1+1) evolutionary Algorithm, is performed and linear functions are proved to be optimized in expected time O(nlnn) but only mutation rates of size (1/n) can ensure this behavior.

TL;DR: The paper outlines the principles underlying the Maude system implementation, including its semicompilation techniques, and explains and illustrates with examples the main concepts of Maude's language design including its underlying logic, functional, system and object-oriented modules, as well as parameterized modules, theories, and views.

TL;DR: Several complexity measures for Boolean functions are discussed: certificate complexity, sensitivity, block sensitivity, and the degree of a representing or approximating polynomial, and how they give bounds for the decision tree complexity of Boolean functions on deterministic, randomized, and quantum computers.

TL;DR: In this article, the authors propose inheritance-preserving transformation rules for workflow processes and show that these rules can be used to avoid problems such as the "dynamic change bug." The dynamic change bug refers to errors introduced by migrating a case (i.e., a process instance) from an old process definition to a new one.

TL;DR: The present paper presents the basic ideas of computing with membranes and some fundamental properties (mostly concerning the computational power and efficiency) of P systems of various types.

TL;DR: A model for real-time systems augmented with discrete probability distributions based on the timed automata model of Alur and Dill is presented and two approaches to model checking are introduced.

TL;DR: This is the first comprehensive study of variants of the Stable Marriage Problem in which the preference lists of the participants are not necessarily complete and not necessarily totally ordered, and gives a 2-approximation algorithm for the problems of finding a stable matching of maximum or minimum size.

TL;DR: This paper summarizes one variety of approaches to the semantics of logic programs: that based on fixpoint theory, and hopes readers will see parallels with, and the divergences from the better known fixpoint treatments developed for other programming methodologies.

TL;DR: A unified enumerative and asymptotic theory of directed two-dimensional lattice paths in half-planes and quarter-planes based on a specific “kernel method” that provides an important decomposition of the algebraic generating functions involved, as well as a generic study of singularities of an associated algebraic curve.

TL;DR: The main emphasis of this paper is the treatment of operational semantics, notions of equivalence, and (sound and complete) axiomatisations of these equivalences for different types of Markovian process algebras, where delays are governed by exponential distributions.

TL;DR: The criteria for separability and quantum entanglement are reviewed, both in a bipartite as well as a multipartite setting, and how these criteria bear on the experimental detection of quantumEntanglement is indicated.

TL;DR: This paper provides an overview of recent developments concerning the process of local majority voting in graphs, and its basic properties, from graph theoretic and algorithmic standpoints.

TL;DR: An overview of the CASL design is given, and all the main concepts and constructs of CASL are briefly explained and illustrated -- the reader is referred to the CASl Language Summary for further details.

TL;DR: The theory and applications of rewriting logic have been vigorously developed by researchers all over the world during the past eleven years and several language implementations and a variety of formal tools have been developed and have been used in a wide range of applications.

TL;DR: This work derives the big-step semantics, termination and nontermination semantics, Plotkin's natural, Smyth's demoniac and Hoare's angelic relational semantics and equivalent nondeterministic denotational semantics from the maximal trace semantics of a transition system.

TL;DR: The relations between searching games with errors and problems concerning communication through a noisy channel and error-correcting codes are shown, and a taxonomy of such games is given, depending on the type of questions allowed, on the degree of interactivity between the players, and on the imposed limitations on errors.

TL;DR: A deterministic local search algorithm for k-SAT running in time (2-2/(k+ 1))n up to a polynomial factor is described, which is better than all previous bounds for deterministic k- SAT algorithms.

TL;DR: The 2-way quantum finite automata with quantum and classical states (2qcfa's) model as discussed by the authors is a variant of the classical 2qfa model, which may be simpler to implement than unrestricted 2qFa's; the internal state of a 2Qcfa may include a quantum part that may be in a mixed quantum state, but the tape head position is required to be classical.

TL;DR: It is shown that Par can be made into an equivalence of 2-categories between MCat and a 2-category of restriction categories, and deduce the completeness and cocompleteness of the 2-Categories of M-c categories and of restriction category.

TL;DR: It is proved that admissible representations δx, δy of topological spaces x,y have the desirable property that every partial function f :⊆ X → Y is continuously realizable with respect to δ x,δy if and only if f is sequentially continuous.

TL;DR: This paper introduces authentication tests and proves their soundness by giving new and straightforward proofs of security goals for several protocols, and illustrates how to use the authentication tests as a heuristic for finding attacks against incorrect protocols.

TL;DR: This top-down refutation procedure overcomes failure situations in the unification process by using the similarity relation, and can lead to the implementation of a more general PROLOG interpreter, without detracting from the elegance of the language.

TL;DR: The type system is extended to the new constructs, and it is shown that noninterference still holds, while remaining in a nonprobabilistic setting.

TL;DR: This paper has three contributions: a presentation of the concepts of rules and strategies available in ELAN, an expression of rewrite rules with matching conditions in conditional rewriting logic, and an enrichment mechanism of a rewrite theory into a strategy theory in conditional rewrite logic.

TL;DR: This work defines a query automaton (QA) as a deterministic two-way finite automaton over trees that has the ability to select nodes depending on the state and the label at those nodes, and establishes the complexity of the non-emptiness, containment, and equivalence of QAs to be complete for EXPTIME.

TL;DR: The history of attempts to analyse evolutionary algorithms is described and then new methods for continuous as well as discrete search spaces are presented and discussed.

TL;DR: It is shown that automata of this kind characterise expressive power of monadic second-order logic (MSOL) over tree-like structures and it is proved that MSOL theory of a tree- like structure is effectively reducible to that of the original structure.

TL;DR: It is proved that the frequencies of the factors in a strong sense do exist for all episturmian words.

TL;DR: An Almost No Free Lunch (ANFL) theorem shows that for each function which can be optimized efficiently by a search heuristic there can be constructed many related functions where the same heuristic is bad.

TL;DR: This paper explores the application of rewriting logic to the executable formal modeling of real-time and hybrid systems, and gives general techniques by which such systems can be specified as ordinary rewrite theories.