OSA: an Integration Platform for Component-Based Simulation

Poster abstract.International audienceMany discrete-event simulators are developed concurrently, but with identical or similar purpose. This poster presents the Open Simulation Architecture (OSA), a discrete-event component-based simulation platform whose goal is to favor the reuse and integration of simulation software components and models. To favor reuse, OSA uses a layered approach to combine the modeling, simulation, and related concerns, such as instrumentation or deployment. OSA is both a testbed for experimenting new simulation techniques and a tool for real case studies. The ability of OSA to support challenging studies is illustrated by a Peer-to-peer system case study involving millions of components

Formulation en Coupe/Rounds pour le Routage dans les réseaux radio maillés

National audienceUn des problèmes au coeur de l'optimisation des réseaux radio maillés est le routage et l'ordonnancement d'appels. Dans cet article, nous étudions une relaxation classique de ce problème qui consiste à répartir la capacité entre les ensembles d'appels simultanés de manière à garantir un débit suffisant à chaque routeur du réseau. Nous introduisons une nouvelle formulation s'affranchissant du routage pour se concentrer sur la capacité de transport disponible sur les coupes du réseau. Nous prouvons son équivalence avec les formulations existantes et présentons un processus efficace de résolution par génération croisée de lignes et de colonnes

Reliability of Connections in Multilayer Networks under Shared Risk Groups and Costs Constraints

International audienceThe notion of Shared Risk Resource Groups (SRRG) has been introduced to capture survivability issues when a set of resources may fail simultaneously. Applied to Wavelength Division Multiplexing Network (WDM), it expresses that some links and nodes may fail simultaneously. The reliability of a connection therefore depends on the number of SRRGs through which it is routed. Consequently, this number has to be minimized. This problem has been proved NP-complete and hard to approximate in general, even when routing a single request. Some heuristics using shortest paths have already been designed, however the cost (the usual routing cost, not in term of SRRG) was not part of the objective. In this paper we study the problem of minimizing a linear combination of the average number of SRRG per paths and the cost of the routing. The main result of our work is a column generation formulation that allows to solve efficiently the problem of maximizing the reliability of a set of connection requests in MPLS/WDM mesh networks with SRRGs while keeping the cost of the routing low

Influence of Experience on Performance of Individual Surgeons in Thyroid Surgery: Prospective Cross Sectional Multicentre Study

Objective: To determine the association between surgeons’ experience and postoperative complications in thyroid surgery. Design: Prospective cross sectional multicentre study. Setting: High volume referral centres in five academic hospitals in France. Participants: All patients who underwent a thyroidectomy undertaken by every surgeon in these hospitals from 1 April 2008 to 31 December 2009. Main outcome measures: Presence of two permanent major complications (recurrent laryngeal nerve palsy or hypoparathyroidism), six months after thyroid surgery. We used mixed effects logistic regression to determine the association between length of experience and postoperative complications. Results: 28 surgeons completed 3574 thyroid procedures during a one year period. Overall rates of recurrent laryngeal nerve palsy and hypoparathyroidism were 2.08% (95% confidence interval 1.53% to 2.67%) and 2.69% (2.10% to 3.31%), respectively. In a multivariate analysis, 20 years or more of practice was associated with increased probability of both recurrent laryngeal nerve palsy (odds ratio 3.06 (1.07 to 8.80), P=0.04) and hypoparathyroidism (7.56 (1.79 to 31.99), P=0.01). Surgeons’ performance had a concave association with their length of experience (P=0.036) and age (P=0.035); surgeons aged 35 to 50 years had better outcomes than their younger and older colleagues. Conclusions: Optimum individual performance in thyroid surgery cannot be passively achieved or maintained by accumulating experience. Factors contributing to poor performance in very experienced surgeons should be explored further

Seismotectonics of southeast France: from the Jura mountains to Corsica

The analysis of the seismicity catalog (1996 to 2019) covering the region from the Jura mountains to Corsica provides a first-order image of the distribution of earthquakes, highlighting large structures such as the Briançonnais and Piedmontais seismic arcs, the eastward deepening of the focal depths through the Western Alps, several large active faults (e.g. Belledonne, Middle Durance, Ligure). Over this period the magnitudes are moderate and the focal mechanisms of the main events display a diversity of seismic behaviors that can be explained by the complexity of the different geological domains with a more or less strong structural inheritage, by variable rheological characteristics at the scale of the crust and by the joint action of different mechanisms of deformation. The distribution of the historical events is in fairly good agreement with the instrumental seismicity, but several earthquakes of $M >6$ are highlighted since the 14th century until the beginning of the 20th

Seismotectonics of southeast France: from the Jura mountains to Corsica

The analysis of the seismicity catalog (1996 to 2019) covering the region from the Jura mountains to Corsica provides a first-order image of the distribution of earthquakes, highlighting large structures such as the Briançonnais and Piedmontais seismic arcs, the eastward deepening of the focal depths through the Western Alps, several large active faults (e.g. Belledonne, Middle Durance, Ligure). Over this period the magnitudes are moderate and the focal mechanisms of the main events display a diversity of seismic behaviors that can be explained by the complexity of the different geological domains with a more or less strong structural inheritage, by variable rheological characteristics at the scale of the crust and by the joint action of different mechanisms of deformation. The distribution of the historical events is in fairly good agreement with the instrumental seismicity, but several earthquakes of $M >6$ are highlighted since the 14th century until the beginning of the 20th

Rapid response to the M_w 4.9 earthquake of November 11, 2019 in Le Teil, Lower Rhône Valley, France

On November 11, 2019, a Mw 4.9 earthquake hit the region close to Montelimar (lower Rhône Valley, France), on the eastern margin of the Massif Central close to the external part of the Alps. Occuring in a moderate seismicity area, this earthquake is remarkable for its very shallow focal depth (between 1 and 3 km), its magnitude, and the moderate to large damages it produced in several villages. InSAR interferograms indicated a shallow rupture about 4 km long reaching the surface and the reactivation of the ancient NE-SW La Rouviere normal fault in reverse faulting in agreement with the present-day E-W compressional tectonics. The peculiarity of this earthquake together with a poor coverage of the epicentral region by permanent seismological and geodetic stations triggered the mobilisation of the French post-seismic unit and the broad French scientific community from various institutions, with the deployment of geophysical instruments (seismological and geodesic stations), geological field surveys, and field evaluation of the intensity of the earthquake. Within 7 days after the mainshock, 47 seismological stations were deployed in the epicentral area to improve the Le Teil aftershocks locations relative to the French permanent seismological network (RESIF), monitor the temporal and spatial evolution of microearthquakes close to the fault plane and temporal evolution of the seismic response of 3 damaged historical buildings, and to study suspected site effects and their influence in the distribution of seismic damage. This seismological dataset, completed by data owned by different institutions, was integrated in a homogeneous archive and distributed through FDSN web services by the RESIF data center. This dataset, together with observations of surface rupture evidences, geologic, geodetic and satellite data, will help to unravel the causes and rupture mechanism of this earthquake, and contribute to account in seismic hazard assessment for earthquakes along the major regional Cévenne fault system in a context of present-day compressional tectonics

Distribution de programmes synchrones : Le cas d'Esterel

The realization of modern embedded systems increase the requirements of automatic or semi-automatic code distributing tools. Indeed the evolution of the hardware/software platform use for the realization of such systems turn toward heterogeneous chip network.Within the context of the synchronous language, all of their advantages, the possibility of distributing optimized code make this technologies more attractive.Our works consist connect the Esterel language with existing software, which can make the code distribution. Our final choice is the SynDEx software, because this software use the same theoretical foundation (synchronous systems) than Esterel language.Even, if the SynDEx software and the Esterel language use the same theoretical foundation, the Esterel language and the SynDEx software is different in the way they represent algorithm.Indeed the Esterel language is a imperative and control oriented language, while the SynDEx software is data flow oriented. In this circumstances, one part of our work consisted to transform the representation of Esterel program to data flow representation. Furthermore, in the goal of increase the evaluation of programs we exploit the structural information of the program to minimize the really active part of the program.La réalisation des systèmes embarqués modernes a fait naître le besoin de techniques et outils d'aide à la distribution automatique ou semi-automatique de code. En effet, l'évolution de la plate-forme matérielle/logicielle utilisée pour la réalisation de tels systèmes a tendance à s'orienter vers des réseaux et architectures de processeurs hétérogènes. Dans le cadre des langages synchrones, qui offrent déjà de nombreux avantages liés à une sémantique formelle (Model based design, outils de vérification...), la possibilité de distribution optimisée de code rendrait ces technologies encore plus . Notre travail a consisté à rapprocher le langage Esterel de logiciels existants permettant d'effectuer de la distribution de code. Notre choix final s'est porté sur le logiciel SynDEx, puisque ce dernier a l'immense avantage de reposer sur les même fondements théoriques (systèmes synchrones) que le langage Esterel.Bien que reposant sur les mêmes fondements théoriques, le langage Esterel et le logiciel SynDEx se distinguent par le fait que le premier correspond à un style de langage orienté flot de contrôle tandis que le second utilise pour la représentation des algorithmes un style orienté flot de données. Dans ce contexte, une partie de notre travail a consisté à transformer la représentation des programmes Esterel vers une représentation orientée flot de données