CETTE THESE EST CONSACREE A LA MODELISATION PAR FILES D'ATTENTE DE CERTAINS SYSTEMES INFORMATIQUES. LE CHAPITRE I ANALYSE UN SYSTEME CLASSIQUE DE FILES D'ATTENTE EN SERRE. LES CHAPITRES II, III ET IV ABORDENT L'ANALYSE DE MODELES D'ALLOCATION D'UNE RESSOURCE UNIQUE DANS LES RESEAUX DE COMMUNICATION (BOUCLE, BUS...). CECI SE TRADUIT PAR LA RECHERCHE DE POLITIQUES OPTIMALES DE SERVICE DANS UNE FILE D'ATTENTE MULTICLASSE AVEC CONTRAINTES. LES CHAPITRES V ET VI TRAITENT DE L'EVALUATION DES PERFORMANCES DE DEUX PROTOCOLES DE COMMUNICATION MULTI-ACCES

CETTE THESE EST CONSACREE A LA MODELISATION PAR FILES D'ATTENTE DE CERTAINS SYSTEMES INFORMATIQUES. LE CHAPITRE I ANALYSE UN SYSTEME CLASSIQUE DE FILES D'ATTENTE EN SERRE. LES CHAPITRES II, III ET IV ABORDENT L'ANALYSE DE MODELES D'ALLOCATION D'UNE RESSOURCE UNIQUE DANS LES RESEAUX DE COMMUNICATION (BOUCLE, BUS...). CECI SE TRADUIT PAR LA RECHERCHE DE POLITIQUES OPTIMALES DE SERVICE DANS UNE FILE D'ATTENTE MULTICLASSE AVEC CONTRAINTES. LES CHAPITRES V ET VI TRAITENT DE L'EVALUATION DES PERFORMANCES DE DEUX PROTOCOLES DE COMMUNICATION MULTI-ACCES

Promoting original mathematical methods to determine the invariant measure of two-dimensional random walks in domains with boundaries, the authors use Using Riemann surfaces and boundary value problems to propose completely new approaches to solve functional equations of two complex variables. These methods can also be employed to characterize the transient behavior of random walks in the quarter plane.

AISB91 is the eighth conference organized by the Society for the Study of Artificial Intelligence and Simulation of Behaviour. It is not only the oldest regular conference in Europe on AI - which spawned the ECAI conferences in 1982 - but it is also the conference that has a tradition for focusing on research as opposed to applications. The 1991 edition of the conference was no different in this respect. On the contrary, research, and particularly newly emerging research dir ections such as knowledge level expert systems research, neural networks and emergent functionality in autonomous agents, was strongly emphasised. The conference was organized around the following sessions: dis tributed intelligent agents, situatedness and emergence in autonomous agents, new modes of reasoning, the knowledge level perspective, and theorem proving and machine learning. Each of these sessions is discussed below in more detail. DISTRIBUTED INTELLIGENT AGENTS Research in distributed AI is concerned with the problem of how multiple agents and societies of agents can be organized to co-operate and collectively solve a problem. The first paper by Chakravarty (MIT) focuses on the problem of evolving agents in the context of Minsky's society of mind theory. It addesses the question of how new agents can be formed by transforming existing ones and illustrates the theory with an example from game playing. Smieja (GMD, Germany) focuses on the problem of organizing networks of agents which consist internally of neural networks.