11 research outputs found

    Adaptation d'un algorithme optimal d'ordonnancement en régime permanent pour des lots bornés

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    International audienceLe contexte de cet article est l ordonnancement de lots bornes de travaux identiques sur une plate-forme d execution heterogene comme la grille. Les travaux executes sont des graphes de t?ches orientes et sans cycle (DAG), en forme d anti-arbre. Les t?ches sont de plusieurs types et les n{oe}uds de la plate-forme ne sont pas toujours en mesure d executer tous les types de t?ches. Le probleme de minimisation du temps d execution d un lot est un probleme NP-Complet. Sous l angle du regime permanent, il est possible de decrire le probleme sous la forme d un programme lineaire donnant une solution optimale pour l ordonnancement cyclique de lots infinis. Lorsque les lots sont bornes, les resultats restent bons bien que sous optimaux. Nous montrons ici que les phases d initialisation et de terminaison ajoutent un sur-co?t qui penalise le temps global d execution. Nous montrons ensuite le lien entre la taille de ces phases et la taille de la periode de l ordonnancement cyclique et donnons un algorithme permettant le calcul de la periode minimale. Des experimentations, obtenues par simulations avec SimGrid, illustrent en fin d article le gain apporte par le choix d une periode minimal

    Processing Identical Workflows on {SOA} Grids: Comparison of Three Approaches

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    International audienceIn this paper we consider the scheduling of a batch of workflows on a service oriented grid. A job is represented by a directed acyclic graph without forks (intree) but with typed tasks. The processors are distributed and each processor have a set of services that carry out equivalent task types. The objective function is to minimize the makespan of the batch execution. Three algorithms are studied in this context: an on-line algorithm, a genetic algorithm and a steady-state algorithm. The contribution of this paper is on the experimental analysis of these algorithms and on their adaptation to the context. We show that their performances depend on the size and complexity of the batch and on the characteristics of the execution platform. end{abstract

    Comparison of Batch Scheduling for Identical Multi-Tasks Jobs on Heterogeneous Platforms

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    International audienceIn this paper we consider the scheduling of a batch of the same job on a heterogeneous execution platform. A job is represented by a directed acyclic graph without forks (intree) but with typed tasks. The execution resources are distributed and each resource can carry out a set of task types. The objective function is to minimize the makespan of the batch execution. Three algorithms are studied in this context: an on-line algorithm, a genetic algorithm and a steady-state algorithm. The contribution of this paper is on the experimental analysis of these algorithms and on their adaptation to the context. We show that their performances depend on the size of the batch and on the characteristics of the execution platform

    Steady-State for Batches of Identical Task Graphs

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    International audienceIn this paper, we focus on the problem of scheduling batches of identical task graphs on a heterogeneous platform, when the task graph consists in a tree. We rely on steady-state scheduling, and aim at reaching the optimal throughput of the system. Contrarily to previous studies, we concentrate upon the scheduling of batches of limited size. We try to reduce the processing time of each instance, thus making steady-state scheduling applicable to smaller batches. The problem is proven NP-complete, and a mixed integer program is presented to solve it. Then, different solutions, using steady-state scheduling or not, are evaluated through comprehensive simulations

    Assessing new approaches to schedule a batch of identical intree-shaped workflows on a heterogeneous platform

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    International audienceIn this paper, we consider the makespan optimisation when scheduling a batch of identical workflows on a heterogeneous platform as a service-oriented grid or a micro-factory. A job is represented by a directed acyclic graph (DAG) with typed tasks and no fork nodes (in-tree precedence constraints). The processing resources are able to process a set of task types, each with unrelated processing cost. The objective function is to minimise the execution makespan of a batch of identical workflows while most of the works concentrate on the throughput in this case. Three algorithms are studied in this context: a classical list algorithm and two algorithms based on new approaches, a genetic algorithm and a steady-state algorithm. The contribution of this paper is both on the adaptation of these algorithms to the particular case of batches of identical workflows and on the performance analysis of these algorithms regarding the makespan. We show the benefits of their adaptation, and we show that the algorithm performance depends on the structure of the workflow, on the size of the batch and on the platform characteristics

    Preventive and Curative treatment of malaria during pregnancy in Mali: Evaluation of the Healthcare Professionals based on the Malian National Malaria Control Program (NMCP) Guidelines

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    Malaria infections in pregnancy should be treated promptly with safe and efficacious antimalarial drugs to prevent harmful effects on the mother and fetus. To succeed, the Malian has developed NMCP guidelines for the management of malaria cases in pregnant women. The study aimed at the analysis of the prescription of antimalarial drugs based on the Mali's NMCP guidelines. We conducted a cross-sectional study during malaria transmission season from June to August 2020. The sampling concerned all prescriptions for pregnant women containing at least one antimalarial drug. The frequency of prescription of antimalarial drugs was 85%. 132 (74.16%) were preventive treatments and 46 (25.84%) curative treatments. 30 (90.91%) of pregnant women in the first trimester received one dose of Sulfadoxine-Pyrimethamine. 6 (12.5%) received three doses in the third trimester. Of the 46 antimalarial drugs prescribed for the treatment of uncomplicated malaria, 30 (65.22%) were Artemether-lumefantrine (tablet), 10 (21.74%) were Quinine (tablet). 29 (63.04%) were compliant with NMCP guidelines and 17 (36.96%) were not. The non-compliances concerned 3 prescriptions of Artemether-lumefantrine in the first trimester, 3 and 5 prescriptions of Quinine (tablet) in the second and third trimester respectively and at the end 2 and 4 non-compliances respectively for the prescription of injectable dosage forms of Quinine and Artesunate. This study showed a great noncompliance with the Mali's NMCP guidelines in the prescription of antimalarial in pregnant women. Chemoprophylaxis should be prohibited in the first trimester.   Keywords: Curative and Preventive Treatment, Malaria in Pregnancy, Malaria Transmission, Mal

    Spatio-Temporal Dynamic of Malaria Incidence: A Comparison of Two Ecological Zones in Mali

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    International audienceMalaria transmission largely depends on environmental, climatic, and hydrological conditions. In Mali, malaria epidemiological patterns are nested within three ecological zones. This study aimed at assessing the relationship between those conditions and the incidence of malaria in Dangassa and Koila, Mali. Malaria data was collected through passive case detection at community health facilities of each study site from June 2015 to January 2017. Climate and environmental data were obtained over the same time period from the Goddard Earth Sciences (Giovanni) platform and hydrological data from Mali hydraulic services. A generalized additive model was used to determine the lagged time between each principal component analysis derived component and the incidence of malaria cases, and also used to analyze the relationship between malaria and the lagged components in a multivariate approach. Malaria transmission patterns were bimodal at both sites, but peak and lull periods were longer lasting for Koila study site. Temperatures were associated with malaria incidence in both sites. In Dangassa, the wind speed (p = 0.005) and river heights (p = 0.010) contributed to increasing malaria incidence, in contrast to Koila, where it was humidity (p < 0.001) and vegetation (p = 0.004). The relationships between environmental factors and malaria incidence differed between the two settings, implying different malaria dynamics and adjustments in the conception and plan of interventions

    Gaia Early Data Release 3 - Catalogue validation

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    International audienceContext. The third Gaia data release is published in two stages. The early part, Gaia EDR3, gives very precise astrometric and photometric properties for nearly two billion sources together with seven million radial velocities from Gaia DR2. The full release, Gaia DR3, will add radial velocities, spectra, light curves, and astrophysical parameters for a large subset of the sources, as well as orbits for solar system objects.Aims. Before the publication of the catalogue, many different data items have undergone dedicated validation processes. The goal of this paper is to describe the validation results in terms of completeness, accuracy, and precision for the Gaia EDR3 data and to provide recommendations for the use of the catalogue data.Methods. The validation processes include a systematic analysis of the catalogue contents to detect anomalies, either individual errors or statistical properties, using statistical analysis and comparisons to the previous release as well as to external data and to models.Results. Gaia EDR3 represents a major step forward, compared to Gaia DR2, in terms of precision, accuracy, and completeness for both astrometry and photometry. We provide recommendations for dealing with issues related to the parallax zero point, negative parallaxes, photometry for faint sources, and the quality indicators
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