Slider : un Raisonneur Incrémental Évolutif

National audienceThe main drawbacks of current reasoning methods over ontologies are they struggle to provide scalability for large datasets. The batch processing reasoners who provide the best scalability so far are unable to infer knowledge from evolving data. We contribute to solving these problems by introducing Slider, an efficient incremental reasoner. Slider exhibits a performance improvement by more than a 70% compared to the OWLIM-SE reasoner. Slider is conceived to handle expanding data from streams with a growing background knowledge base. It natively supports ρdf and RDFS, and its architecture allows to extend it to more complex fragments with a minimal effort.Les solutions existantes pour le raisonnement incrémental souffrent principalement de leur incapacité à prendre en charge des ontologies complexes et ne sont pas conçues pour gérer de grandes quantités de connaissances. Dans cet article, nous présentons Slider (Chevalier et al. (2015)), un raisonneur incrémental évolutif par chaînage avant, permettant de raisonner sur des flux de données sémantiques

Gestion de flux de données pour l'observation de systèmes

La popularisation de la technologie a permis d'implanter des dispositifs et des applications de plus en plus développés à la portée d'utilisateurs non experts. Ces systèmes produisent des flux ainsi que des données persistantes dont les schémas et les dynamiques sont hétérogènes. Cette thèse s'intéresse à pouvoir observer les données de ces systèmes pour aider à les comprendre et à les diagnostiquer. Nous proposons tout d'abord un modèle algébrique Astral capable de traiter sans ambiguïtés sémantiques des données provenant de flux ou relations. Le moteur d'exécution Astronef a été développé sur l'architecture à composants orientés services pour permettre une grande adaptabilité. Il est doté d'un constructeur de requête permettant de choisir un plan d'exécution efficace. Son extension Asteroid permet de s'interfacer avec un SGBD pour gérer des données persistantes de manière intégrée. Nos contributions sont confrontées à la pratique par la mise en œuvre d'un système d'observation du réseau domestique ainsi que par l'étude des performances. Enfin, nous nous sommes intéressés à la mise en place de la personnalisation des résultats dans notre système par l'introduction d'un modèle de préférences top-k.Due to the popularization of technology, non-expert people can now use more and more advanced devices and applications. Such systems produce data streams as well as persistent data with heterogeneous schemas and dynamics. This thesis is focused on monitoring data coming from those systems to help users to understand and to perform diagnosis on them. We propose an algebraic model Astral able to treat data coming from streams or relations without semantic ambiguity. The engine Astronef has been developed on top of a service-oriented component framework to enable a large adaptability. It embeds a query builder which can select a composition of components to provide an efficient query plan. Its extension Asteroid interfaces with a DBMS in order to manage persistent data in an integrated manner. Our contributions have been confronted to practice with the deployment of a monitoring system for the digital home and with a performance study. Finally, we extend our approach with an operator to personalize the results by introducing a top-k preference model.SAVOIE-SCD - Bib.électronique (730659901) / SudocGRENOBLE1/INP-Bib.électronique (384210012) / SudocGRENOBLE2/3-Bib.électronique (384219901) / SudocSudocFranceF

Factors Influencing Customer Satisfaction towards E-shopping in Malaysia

Online shopping or e-shopping has changed the world of business and quite a few people have decided to work with these features. What their primary concerns precisely and the responses from the globalisation are the competency of incorporation while doing their businesses. E-shopping has also increased substantially in Malaysia in recent years. The rapid increase in the e-commerce industry in Malaysia has created the demand to emphasize on how to increase customer satisfaction while operating in the e-retailing environment. It is very important that customers are satisfied with the website, or else, they would not return. Therefore, a crucial fact to look into is that companies must ensure that their customers are satisfied with their purchases that are really essential from the ecommerce’s point of view. With is in mind, this study aimed at investigating customer satisfaction towards e-shopping in Malaysia. A total of 400 questionnaires were distributed among students randomly selected from various public and private universities located within Klang valley area. Total 369 questionnaires were returned, out of which 341 questionnaires were found usable for further analysis. Finally, SEM was employed to test the hypotheses. This study found that customer satisfaction towards e-shopping in Malaysia is to a great extent influenced by ease of use, trust, design of the website, online security and e-service quality. Finally, recommendations and future study direction is provided. Keywords: E-shopping, Customer satisfaction, Trust, Online security, E-service quality, Malaysia