Article history: Received 27 July 2010 Accepted after revision 22 November 2010 Available online 24 December 2010 Presented by Marc Yor We consider the problem of a particle subject to Brownian motion in a 2D circular domain with reflecting boundaries except for an absorbing gate. An exact solution for the mean first escape time is given for a gate of any size. Also obtained is the exact probab...

Multimedia desktop conferencing systems are gaining momentum and increasingly becoming a reality. In these systems, besides using audio, video and multi-user applications, users can share a vast number of single-user applications for collaborative work. In these systems, there are two basic architectures for sharing single-user applications, centralized and replicated. In this paper, we present...

— We construct and analyze efficient fully discrete Galerkin type methods, that are of high order of accuracy and conservative in the L sense,for approximating the solution ofaform of the linear Schrödinger équation with a time-dependent coefficient, found e.g. in underwater acoustics. The time stepping procedures are based on the class of implicit Runge-Kutta methods known as the q-stage Gauss...

— In a recent paper the first two authors showed that a convenient choice of « bubble tensors » leads to a significant réduction of the number of degrees offreedom needed to definefinite element spaces for the extra stresses, suitablefor the solution of viscoelastic flow problems. In this context specialists' usual guiding criterion is a stable and accurate approximation of the underlying linea...

The authors develop empirical likelihood (EL) based methods of inference for a common mean using data from several independent but nonhomogeneous populations. For point estimation, they propose a maximum empirical likelihood (MEL) estimator and show that it is √ n -consistent and asymptotically optimal. For confidence intervals, they consider two EL based methods and show that both intervals ha...

This work presents an approach to circumvent one of the major problems with techniques to build and apply software quality estimation models, namely the use of precise metric thresholds values. We used a fuzzy logic based approach to investigate the stability of a reusable class library interface, using structural metrics as stability indicators. To evaluate this new approach, we conducted a st...

In this article we prove that the poset of m-divisible noncrossing partitions is EL-shellable for every wellgenerated complex reflection group. This was an open problem for type G(d, d, n) and for the exceptional types, for which a proof is given case-by-case. Résumé. Dans cet article nous prouvons que l’ensemble ordonné des partitions non-croisées m-divisibles est ELépluchable (“EL-shellable”)...

Le temps nécessaire pour écouter un flux audio est un facteur réduisant l’accès efficace à de grandes archives de parole. Une première approche, la structuration automatique des données, permet d’utiliser un moteur de recherche pour cibler plus rapidement l’information. Les listes de résultats générées sont longues dans un souci d’exhaustivité. Alors que pour des documents textuels, un coup d’o...

L’auto-stabilisation garantit qu’à la fin d’une période de fautes transitoires, un système réparti retrouve de lui-même un comportement correct en un temps fini. La spéculation consiste à garantir que le système soit correct pour toute exécution mais possède des performances significativement meilleures pour un sous-ensemble d’exécutions qui sont supposées plus probables. Un protocole spéculati...

RÉSUMÉ. Cet article montre comment nous utilisons la technologie agent pour traiter les problèmes de coopération et de coordination de processus dans le contexte du Workflow Inter-Organisationnel (WIO) lâche. Le WIO a pour but de faire collaborer des processus issus et s’exécutant dans différentes organisations réparties, autonomes et hétérogènes. Le WIO lâche correspond à une coopération occas...