A Rewriting Based Model for Probabilistic Distributed Object Systems

Concurrent and distributed systems have traditionally been modelled using nondeterministic transitions over configurations. The nondeterminism provides an abstraction over scheduling, network delays, failures and randomization. However a probabilistic model can capture these sources of nondeterminism more precisely and enable statistical analysis, simulations and reasoning. We have developed a general semantic framework for probabilistic systems using probabilistic rewriting. Our framework also allows nondeterminism in the system. In this paper, we briefly describe the framework and its application to concurrent object based systems such as actors. We also identify a su#ciently expressive fragment of the general framework and describe its implementation. The concepts are illustrated by a simple client-server example

About Learning Discrete Mathematics at Bulgarian School

The present work is dedicated to the learning discrete mathematics at Bulgarian school. A review of syllabuses and standards has been made. A project of learning discrete mathematics elements from first to twelve class is proposed

Correct and Complete (Positive) Strategy Annotations for OBJ

AbstractStrategy annotations are used in several rewriting-based programming languages to introduce replacement restrictions aimed at improving efficiency and/or reducing the risk of nontermination. Unfortunately, rewriting restrictions can have a negative impact on the ability to compute normal forms. In this paper, we first ascertain/clarify the conditions ensuring correctness and completeness (regarding normalization) of computing with strategy annotations. Then, we define a program transformation methodology for (correct and) complete evaluations which applies to OBJ-like languages

The Timed Concurrent Constraint language in practice

We propose the tccp language for the specification and verification of security protocols. We study the relation between tccp and utcc by presenting a transformation from utcc into tccp that formally states the relation between the two languages. Finally, we present an interpreter for tccp implemented in Maude.Lescaylle Daudinot, A. (2009). The Timed Concurrent Constraint language in practice. http://hdl.handle.net/10251/14517Archivo delegad

Actes du troisième colloque de l’Association de didacticiens des mathématiques africains : ADiMA 3 : approche interdisciplinaire dans l'enseignement et l'apprentissage des mathématiques : quels projets et quels enjeux pour l'Afrique?

« Le colloque ADIMA 3 se situe dans les activités de l’Association de Didacticiens des Mathématiques Africains (ADIMA) reconnu comme une conférence régionale de l’ International Commission of Mathematical Instruction (ICMI). Le colloque vise à contribuer au développement de la recherche en didactique des mathématiques et des sciences et des techniques à tous les niveaux de l'enseignement, avec un souci particulier pour le développement de nouvelles recherches et pour le dialogue avec les mathématiciens, les physiciens, les informaticiens, les mécaniciens, etc. D’une envergure internationale et le colloque ADiMA 3 s’adressait aux chercheurs, formateurs et enseignants qui s’intéressent aux mathématiques et à leur enseignement et à son apprentissage. Le pari de ce troisième colloque scientifique d’ADiMA est de réfléchir sur la question de l’interdisciplinarité par le biais du thème suivant : Approche interdisciplinaire dans l’enseignement et l’apprentissage des mathématiques : quels projets et quels enjeux pour l’Afrique? [...].