18 research outputs found
The Green Computing Observatory: a data curation approach for green IT
International audienceThe first barrier to improved energy efficiency is the difficulty of collecting data on the energy consumption of individual components of data centers, and the lack of overall data collection. GCO collects monitoring data on energy consumption of a large computing center, and publish them through the Grid Observatory. These data include the detailed monitoring of the processors and motherboards, as well as the global site information, such as overall consumption and overall cooling. A second barrier is making the collected data usable. The difficulty is to make the data readily consistent and complete, as well as understandable for further exploitation. For this purpose, GCO opts for an ontological approach in order to rigorously define the semantics of the data (what is measured) and the context of their production (how are they acquired and/or calculated). The Green Computing Observatory (GCO) addresses the previous issues within the framework of a production infrastructure dedicated to e-science, providing a unique facility for the Computer Science and Engineering community. The overall goal is to create a full-fledged data curation process. This paper reports on the first achievements, specifically acquisition and ontology
The Grid Observatory
International audienceThe goal of the Grid Observatory project (GO) is to contribute to an experimental theory of large grid systems by integrating the collection of data on the behaviour of the flagship European Grid Infrastructure (EGI) and its users, the development of models, and an ontology for the domain knowledge. The GO gives access to a database of grid usage traces available to the wider computer science community without the need of grid credentials. The paper presents the architecture of the digital curation process enacted by the GO and examples of their exploitation.L'objectif du projet Grid Observatoiry (GO) est de contribuer à une théorie expérimentale de systèmes globalisés à grande échelle en intégrant l'acquisition de données sur le comportement de l'infrastructure de la grille européenne phare (EGI) et de ses utilisateurs, avec le développement de modèles, et d'une ontologie du domaine. Le GO donne accès à une base de données des traces d'utilisation de la grille, mise à la disposition de la communauté scientifique. L'article présente l'architecture du processus de conservation numérique adoptée par le GO et des exemples de l'exploitation des traces collectées
Traitements interactifs d'images radiologiques et leurs applications cliniques
Medical imaging benefits from the broadening availability of different image sources, not only for diagnostics purpose, but also to evaluate the efficiency of a treatment and guiding surgical procedures. In the mean time, the development of operatory techniques aims for laparoscopic surgery, which allows for a decrease of risks related to the surgical acts and the patient's hospitalization time. However, realizing the surgical procedure under laparoscopy is less intuitive because of the use of cameras with a narrow field of view. We propose new computerized methods which allow for a better interpretation of radiological images, as well as new medical uses for these images. The contributions we present not only affect visualization and processing of data, structure reconstruction, mono- and multi-modal fusion and planning and realization of laparoscopic interventions and punctures, but also industrial imaging. The combined use of different image modalities allows for a better visualization, manipulation and understanding of tridimensional scenes, leading to a better accuracy in the observation and helping take a decision.Le monde médical dispose de plus en plus de sources d'images différentes, non seulement pour réaliser un diagnostic mais aussi pour évaluer l'efficacité d'un traitement et pour être guidé dans les interventions chirurgicales. Parallèlement, le développement des techniques opératoires s'oriente vers la chirurgie non " à ciel ouvert ", notamment la coelioscopie, qui permet de diminuer les risques liés à l'intervention ainsi que le temps d'hospitalisation du patient. En revanche, elle rend moins intuitive la réalisation de l'acte chirurgical, notamment du fait de la vision réduite à l'utilisation d'une ou plusieurs caméras dans la région d'intérêt. Durant ma thèse, j'ai conçu et mis en oeuvre des nouvelles méthodes informatiques de traitement 3D d'images radiologiques ainsi que de nouvelles utilisations médicales de ces images. Les contributions présentées concernent la visualisation et le traitement des données, la segmentation de structures 3D, la fusion mono et multimodale et l'aide à la réalisation d'interventions. Les applications présentées concernent notamment la planification et la réalisation d'interventions sous coelioscopie et de ponctions mais aussi l'imagerie industrielle. L'utilisation conjointe de différentes modalités d'images permet d'améliorer la visualisation, la manipulation et la compréhension de scènes tridimensionnelles, conduisant à une plus grande compréhension des observations et à une meilleure prise de décision
Traitements intéractifs d'images radiologiques et leurs utilisations cliniques
Le monde médical dispose de plus en plus de sources d'images différentes, non seulement pour réaliser un diagnostic, mais aussi pour évaluer l'efficacité d'un traitement et être guidé lors d'interventions chirurgicales. Parallèlement, le développement des techniques opératoires s'oriente vers la chirurgie non "à ciel ouvert", notamment la cœlioscopie, qui permet de diminuer les risques liés à l'intervention ainsi que le temps d'hospitalisation du patient, puisqu'on ne pratique que de très petites incisions pour accéder aux organes ou lésions à soigner. En revanche, elle rend moins intuitive la réalisation de l'acte chirurgical, notamment du fait de la vision réduite à l'utilisation d'une ou plusieurs caméras dans la région d'intérêt. Dans ce mémoire, nous proposons de nouvelles méthodes informatiques permettant d'approfondir l'interprétation des images radiologiques, ainsi que de nouvelles utilisations médicales de ces images. Les contributions présentées concernent la visualisation et le traitement des données, la reconstruction de structures, la fusion mono et multirnodale, ainsi que l'aide à la réalisation d'interventions. Les applications présentées concernent notamment la planification et la réalisation d'interventions sous cœlioscopie et de ponctions, mais aussi l'imagerie industrielle. Dans tous les cas, l'utilisation conjointe de différentes modalités d'images, qu'elles soient issues ou non d'équipements radiologiques, perm d'améliorer la visualisation, la manipulation et la compréhension de scènes tridimensionnelles, conduisant à une plus grande précision de l'observation et à une meilleure prise de décision.Medical imaging benefits from the broadening availability of different image sources, not only for diagnostics purpose, but also to evaluate the efficiency of a treatment and guiding surgical procedures. ln the mean time, the development of operatory techniques aims for laparoscopic surgery, which allows for a decrease ofrisks related to the surgical acts and the patient's hospitalization time. However, realizing the surgical procedure under laparoscopy is less intuitive because 0 the use of cameras with a narrow field ofview. ln this manuscript, we propose new computerized methods which allow for a better interpretation of radiological images, as well as new medical uses for these images. The contributions we present not only affect visualization and processing 0 data, structure reconstruction, mono- and multi-modal fusion and planning and realization of laparoscopic interventions and punctures, but also industrial irnaging. The combined use of different image modalities, being radiological or not, allows for a better visualization, manipulation and understanding of tridimensional scenes, leading to a better accuracy in the observation and helping take a decision.ORSAY-PARIS 11-BU Sciences (914712101) / SudocSudocFranceF
TFT, Tests For Triplestores: Certifying the interoperability of RDF database systems using a continuous delivery workflow
International audience—In March 2013, the W3C recommended SPARQL 1.1 to retrieve and manipulate decentralized RDF data. Real-world usage requires advanced features of Recommendation SPARQL 1.1. As these are not consistently implemented, we propose a software named TFT (Tests For Triplestores) to test the interoperability of the SPARQL endpoint of RDF database sys-tems. To help the developers and end-users of RDF databases, we perform daily tests daily on Jena-Fuseki, Marmotta-KiWistore, 4Store and three other commercial databases. With these tests, we have built a scoring system named SPARQLScore and share our results on the website http://sparqlscore.com
Sequential fault monitoring
International audienceFor large-scale distributed systems, the knowledge component at the core of the MAPE-K loop remains elusive. In the context of end-to-end probing, fault monitoring can be re- casted as an inference problem in the space-time domain. We propose and evaluate Sequential Matrix Factorization (SMF), a fully spatio-temporal method that exploits both the recent advances in matrix factorization for the spatial information and a new heuristics based on historical information. Adaptivity oper- ates at two levels: algorithmically, as the exploration/exploitation tradeoff is controlled by a self-calibrating parameter; and at the policy level, as active learning is required for the most challenging cases of a real-world dataset
The Grid Observatory 3.0 - Towards reproducible research and open collaborations using semantic technologies
EGI Community Forum 2014ID : 69 The Grid Observatory 3.0 -Towards reproducible research and open collaborations using semantic technologies Summary : The Grid Observatory 3.0 evolves the Grid Observatory (G.O.) and Green Computing Observatory (G.C.O.) along the Open Linked Data and reproducible research concepts. The first objective is to make analysis easier and more productive, by addressing the technical heterogeneity of the data (EGI services logs), and the wide range of potential usage. Semantic web technologies address these by (i) creating an OWL ontology of the EGI software architecture, (ii) converting the traces from selected services of the grid into an ontology compatible RDF format and (iii) organizing them in SPARQL-enabled triple stores. These technologies expedite and make transparent the personalized integration of multiple, independent sources, required for analysing the behaviour of the EGI grid, as well as long-term sustainability of the GO and GCO repositories. Moreover, the scientist's activity can be exploited to refine the ontology in a collective knowledge building process The second objective is to encourage reproducible science by providing ways to repeat in silico experiments based on the GO data and stored queries over data and processing algorithms. A catalogue of customizable queries will be provided to show examples of queries and processing over the published data. Cloud-based hosting and processing capabilities will be offered to scientists to store and share their processes and algorithms through a collaborative platform in order to encourage open collaborations
Certifying the interoperability of RDF database systems
International audienceIn March 2013, the W3C recommended SPARQL 1.1 to retrieve and manipulate decentralized RDF data. Real-world usage requires advanced features of SPARQL 1.1. recommendations As these are not consistently implemented, we propose a test framework named TFT (Tests for Triple stores) to test the interoperability of the SPARQL end-point of RDF database systems. This framework can execute the W3C's SPARQL 1.1 test suite and also its own tests of interoperability. To help the developers and end-users of RDF databases, we perform daily tests on Jena-Fuseki, Marmotta-KiWistore, 4Store and three other commercial databases. With these tests, we have built a scoring system named SPARQLScore and share our results on the website http://sparqlscore.com