25 research outputs found
XtremWeb : une plate-forme de recherche sur le calcul global et pair à pair
ISBN 274620472XLa connection à grande échelle des ordinateurs aux réseaux de communication et les mécanismes qui permettent leur interopérabilité (standardisation des protocoles, homogénéisation des formats d'échange, systèmes de nomage efficace, sécurisation des sites) motivent des tentatives de globalisation des ressources et des données à partir de systèmes de Calcul Global, Pair à Pair ou de GRID. Ces systèmes sont les prémisses de l'émergence de systèmes d'exploitation à grande échelle. Dans cet article nous proposons d'abord de situer les systémes Pair à Pair par rapport aux autres structures de GRID en soulignant leur différences qui ont principalement une origine historique. Dans une deuxième partie nous présentons une ratio- nalisation des systémes de Calcul Global et Pair à Pair. Nous détaillons ensuite la plate-forme XtremWeb qui constitue l'une des premières tentatives de généralisation du concept de parité entre les ressources appliqué à la globalisation du processeur, de la mémoire et du stockage. Nous terminons par la présentation de quelques points durs en recherche : la sécurisation des participants et la communication inter-noeud
Wheezing in infants: frequency, clinical characteristics and treatment
OBJECTIVE: To estimate the frequency and describe the clinical characteristics and respective treatments of previous history of wheezing. METHODS: Infants aged 6-23 months with upper respiratory tract complaints and reporting previous wheezing were followed-up retrospectively. Data were registered on a validated standardized form. RESULTS: Out of 451 infants, 164 (36.4%; 95%CI: 31.9-41.0) had a report of prior history of wheezing, 148 (32.8%; 95%CI: 28.5-37.4) during the first year of life. The mean age at the first episode of wheezing was 5.3±3.9 months. Among those who had had their first episode before 12 months of age, 38.5% reported 3 to 6 episodes and 14.2% > 6 episodes. Mean age at first episode was lower for those with > 3 episodes in comparison with those with seis episódios. A média da idade no primeiro episódio foi menor para os que apresentaram > três episódios em comparação aos que apresentaram até dois episódios (3,2±2,7 versus 5,7±2,5 meses, p < 0,001). CONCLUSÃO: Um terço dos lactentes apresentou chiado no primeiro ano de vida. Quanto mais cedo ocorre o primeiro episódio, mais frequente é a recorrência do chiado.Fundação de Amparo à Pesquisa do Estado da Bahia (FAPESB)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Universidade Federal da Bahia Faculdade de Medicina da Bahia Programa de Pós-Graduação em Ciências da SaúdeUniversidade Federal de São Paulo (UNIFESP) Escola Paulista de Medicina Departamento de PediatriaUniversidade de São Paulo Faculdade de Saúde Pública Departamento de EpidemiologiaEscola Bahiana de Medicina e Saúde PúblicaUFBAUFBA Faculdade de Medicina da Bahia Departamento de Anatomia Patológica e Medicina LegalUFBA Faculdade de Medicina da Bahia Departamento de PediatriaUNIFESP, EPM, Depto. de PediatriaSciEL
A contribuição do farmacêutico para a promoção do acesso e uso racional de medicamentos essenciais no SUS
Fatores associados à qualidade de vida de cuidadores de idosos em assistência domiciliária
Implante ósseo cortical alógeno conservado em mel na reconstrução de falha óssea diafisária em fêmur de cães: avaliação clínica e radiográfica
XtremWeb : une plate-forme de recherche sur le calcul global et pair à pair
ISBN 274620472XLa connection à grande échelle des ordinateurs aux réseaux de communication et les mécanismes qui permettent leur interopérabilité (standardisation des protocoles, homogénéisation des formats d'échange, systèmes de nomage efficace, sécurisation des sites) motivent des tentatives de globalisation des ressources et des données à partir de systèmes de Calcul Global, Pair à Pair ou de GRID. Ces systèmes sont les prémisses de l'émergence de systèmes d'exploitation à grande échelle. Dans cet article nous proposons d'abord de situer les systémes Pair à Pair par rapport aux autres structures de GRID en soulignant leur différences qui ont principalement une origine historique. Dans une deuxième partie nous présentons une ratio- nalisation des systémes de Calcul Global et Pair à Pair. Nous détaillons ensuite la plate-forme XtremWeb qui constitue l'une des premières tentatives de généralisation du concept de parité entre les ressources appliqué à la globalisation du processeur, de la mémoire et du stockage. Nous terminons par la présentation de quelques points durs en recherche : la sécurisation des participants et la communication inter-noeud
Computing on large-scale distributed systems: XtremWeb architecture, programming models, security, tests and convergence with grid
Global Computing systems belong to the class of large-scale distributed systems. Their properties high computational, storage and communication performance potentials, high resilience make them attractive in academia and industry as computing infrastructures in complement to more classical infrastructures such as clusters or supercomputers. However, generalizing the use of these systems in a multi-user and multi-parallel programming context involves finding solutions and providing mechanisms for many issues such as programming bag of tasks and message passing parallel applications, securing the application, the system itself and the computing nodes, deploying the systems for harnessing resources managed in different ways. In this paper, we present our research, often influenced by user demands, towards a Computational peer-to-peer system called XtremWeb.We describe (a) the architecture of the system and its motivations, (b) the parallel programming paradigms available in XtremWeb and how they are implemented, (c) the deployment issues and what mechanisms are used to harness simultaneously uncoordinated set of resources, and resources managed by batch schedulers and (d) the security issue and how we address, inside XtremWeb, the protection of the computing resources. We present two multi-parametric applications to be used in production: Aires belonging to the high energy physics (HEP) Auger project and a protein conformation predictor using a molecular dynamic simulator. To evaluate the performance and volatility tolerance, we present experiment results for bag of tasks applications and message passing applications. We show that the system can tolerate massive failure and we discuss the performance of the node protection mechanism. Based on the XtremWeb project developments and evolutions, we will discuss the convergence between Global Computing systems and Grid