Search results for " Retrieval"
showing 10 items of 1114 documents
Query-preserving watermarking of relational databases and XML documents
2011
Watermarking allows robust and unobtrusive insertion of information in a digital document. During the last few years, techniques have been proposed for watermarking relational databases or Xml documents, where information insertion must preserve a specific measure on data (for example the mean and variance of numerical attributes). In this article we investigate the problem of watermarking databases or Xml while preserving a set of parametric queries in a specified language, up to an acceptable distortion. We first show that unrestricted databases can not be watermarked while preserving trivial parametric queries. We then exhibit query languages and classes of structures that allow guarante…
Recommandation de parcours de formation dans un contexte mobile
2013
National audience; Les récentes avancées dans les technologies de l'information et de la communication ont vu naître de nouvelles formes d'enseignement. L'apprentissage à distance classique s'enrichit et se transforme pour donner jour à un apprentissage plus flexible, accessible sur de multiples supports, à toute heure et en tout lieu : l'apprentissage mobile. Nos travaux portent sur la conception d'un système de recommandation basé sur le contenu, modélisé en utilisant les technologies du web sémantique. La recommandation prendra en compte l'objectif de formation, mais également les supports disponibles pour dispenser cette formation, les préférences personnelles de l'apprenant, ou encore …
MEDES '10: International ACM Conference on Management of Emergent Digital EcoSystems, Bangkok, Thailand, October 26-29, 2010
2010
International audience
Rules, Photos, and Crowdsourcing for Relationship Type Discovery in Social Networks
2011
International audience
MEDES '11: International ACM Conference on Management of Emergent Digital EcoSystems, San Francisco, CA, USA, November 21-24, 2011
2011
International audience
Special issue on context-aware and mobile multimedia databases and services
2010
International audience
Adding Knowledge Extracted by Association Rules into Similarity Queries
2010
International audience; In this paper, we propose new techniques to improve the quality of similarity queries over image databases performing association rule mining over textual descriptions and automatically extracted features of the image content. Based on the knowledge mined, each query posed is rewritten in order to better meet the user expectations. We propose an extension of SQL aimed at exploring mining processes over complex data, generating association rules that extract semantic information from the textual description superimposed to the extracted features, thereafter using them to rewrite the queries. As a result, the system obtains results closer to the user expectation than i…
Identifying Algebraic Properties to Support Optimization of Unary Similarity Queries
2009
International audience; Abstract. Conventional operators for data retrieval are either based on exact matching or on total order relationship among elements. Neither ofthem is appropriate to manage complex data, such as multimedia data, time series and genetic sequences. In fact, the most meaningful way tocompare complex data is by similarity. However, the Relational Algebra, employed in the Relational Database Management Systems (RDBMS),cannot express similarity criteria. In order to address this issue, we provide here an extension of the Relational Algebra, aimed at representingsimilarity queries in algebraic expressions. This paper identies fundamental properties to allow the integration…