20 research outputs found
Filtrage automatique de courriels : une approche adaptative et multi niveaux
International audienceCet article propose un systĂšme de courriers Ă©lectroniques paramĂ©trable avec plusieurs niveaux de filtrage: un filtrage simple basĂ© sur l'information contenue dans l'entĂȘte du courriel ; un filtrage boolĂ©en basĂ© sur l'existence ou non de mots clĂ©s dans le corps du courriel ; un filtrage vectoriel basĂ© sur le poids de contribution des mots clĂ©s du courriel ; un filtrage approfondi basĂ© sur les propriĂ©tĂ©s linguistiques caractĂ©risant la structure et le contenu du courriel. Nous proposons une solution adaptative qui offre au systĂšme la possibilitĂ© d'apprendre Ă partir de donnĂ©es, de modifier ses connaissances et de s'adapter Ă l'Ă©volution des intĂ©rĂȘts de l'utilisateur et Ă la variation de la nature des courriels dans le temps. De plus, nous utilisons un rĂ©seau lexical permettant d'amĂ©liorer la reprĂ©sentation du courriel en prenant en considĂ©ration l'aspect sĂ©mantique.<BR /
Recent Decisions
International audienceCommunity structure is one of the most prominent features of complex networks. Community structure detection is of great importance to provide insights into the network structure and functionalities. Most proposals focus on static networks. However, finding communities in a dynamic network is even more challenging, especially when communities overlap with each other. In this article , we present an online algorithm, called OLCPM, based on clique percolation and label propagation methods. OLCPM can detect overlapping communities and works on temporal networks with a fine granularity. By locally updating the community structure, OLCPM delivers significant improvement in running time compared with previous clique percolation techniques. The experimental results on both synthetic and real-world networks illustrate the effectiveness of the method
Une approche par apprentissage basée sur des modÚles linguistiques
International audienceNous proposons une double amélioration des systÚmes de filtrage de courriels existants. D'une part, en utilisant une méthode d'apprentissage automatique permettant à un systÚme de filtrage d'élaborer des profils utilisateur. D'autre part, nous utilisons un ensemble de connaissances linguistiques sous forme de modÚles réduits issues de modÚles linguistiques de textes. Dans ce contexte, nous cherchons à évaluer si l'utilisation de connaissances et de traitements linguistiques peut améliorer les performances d'un systÚme de filtrage. En effet, nous utilisons, au-delà des caractéristiques lexicales, un ensemble d'indicateurs sur le message portant sur la structure et le contenu. Ces connaissances sont indépendantes du domaine d'application et la fiabilité repose sur l'opération d'apprentissage. Pour tenter de statuer sur la faisabilité de notre approche et d'évaluer son efficacité, nous l'avons expérimenté sur un corpus de 1 200 messages. Nous présentons les résultats d'un ensemble d'expériences d'évaluation
A New Distributed Chinese Wall Security Policy Model
The application of the Chinese wall security policy model (CWSPM) to control the information flows between two or more competing and/or conflicting companies in cloud computing (Multi-tenancy) or in the social network, is a very interesting solution. The main goal of the Chinese Wall Security Policy is to build a wall between the datasets of competing companies, and among the system subjects. This is done by the applying to the subjects mandatory rules, in order to control the information flow caused between them. This problem is one of the hottest topics in the area of cloud computing (as a distributed system) and has been attempted in the past; however the proposed solutions cannot deal with the composite information flows problem (e.g., a malicious Trojan horses problem), caused by the writing access rule imposed to the subject on the objects. In this article, we propose a new CWSP model, based on the access query type of the subject to the objects using the concepts of the CWSP. We have two types of walls placement, the first type consists of walls that are built around the subject, and the second around the object. We cannot find inside each once wall two competing objects\u27 data. We showed that this mechanism is a good alternative to deal with some previous models\u27 limitations. The model is easy to implement in a distributed system (as Cloud-Computing). It is based on the technique of Object Oriented Programming (Can be used in Cloud computing Software as a service SaaS ) or by using the capabilities as an access control in real distributed system
Approche multicritĂšre de recherche dâinformation structurĂ©e basĂ©e sur lâapprentissage dâordonnancement
Il est connu que, dans la recherche dâinformation, des meilleures performances sont obtenues lorsque plusieurs sources de pertinence sont combinĂ©es en utilisant des mĂ©thodes dâapprentissage dâordonnancement. Dans cet article, nous proposons une approche multicritĂšre pour la recherche dâinformation dans les documents structurĂ©es basĂ©e sur les mĂ©thodes dâapprentissage dâordonnancement pour apprendre automatiquement un modĂšle de Ranking et mesurer lâimpact de chaque source de pertinence. Des expĂ©rimentations sur une grande collection de la compagne dâĂ©valuation de la recherche dâinformation XML (INEX) ont montrĂ© la performance de notre approche.Mot-cles: XML, Recherche dâinformation structurĂ©e, Apprentissage dâordonnancement, Ranking SVM, BM25English AbstractItâs known that, in information retrieval, best performances are obtained when many sources of evidence are combined using learning to rank methods. In this paper, we propose a multiple criteria approach for XML information retrieval based on learning to rank methods to automatically learn a ranking model and measure the impact of each source of evidence. Experiments on a large collection from the XML Information Retrieval evaluation campaign (INEX) showed good performance of the approach.Keywords: XML, structured information retrieval, learning-to-rank, Ranking SVM, BM2
Mécanisme de prédiction pour une plateforme de filtrage collaboratif
Face Ă la quantitĂ© et la rapiditĂ© dâapparition de nouvelles informations le dĂ©veloppement de systĂšmes dâinformation pour cibler au mieux les rĂ©ponses fournies aux utilisateurs afin quâelles soient plus proches de leurs attentes et de leurs goĂ»ts personnels est devenu une nĂ©cessitĂ© incontournable. Les systĂšmes de filtrage collaboratif sâinscrivent parmi ces systĂšmes dâinformation avec certaines particularitĂ©s qui font la diffĂ©rence. Le terme de filtrage collaboratif dĂ©signe les techniques utilisant les goĂ»ts connus dâun groupe dâutilisateurs pour prĂ©dire la prĂ©fĂ©rence inconnue dâun nouvel utilisateur. Cet article dĂ©crit une plateforme de base de filtrage collaboratif qui permet aux utilisateurs la dĂ©couverte de documents intĂ©ressants, grĂące Ă lâautomatisation du processus naturel de recommandation, elle leur permet dâexprimer leurs avis quant Ă la pertinence des documents, selon leurs goĂ»ts et la qualitĂ© quâils perçoivent des documents ; elle offre la possibilitĂ© de bĂ©nĂ©ficier des Ă©valuations sur les documents que dâautres utilisateurs, de profil proche, ont jugĂ©s intĂ©ressants. Tous ces avantages sont apportĂ©s aux utilisateurs par le principe de collaboration, en contrepartie dâun effort individuel : lâĂ©valuation des documents.Mots clĂ©s: Filtrage collaboratif, plateforme, communautĂ©s, prĂ©dictions, recommandationsEnglish Title: Prediction mechanism for a platform of collaborative filteringEnglish AbstractWith the explosive growth of the quantity of new information the development of information systems to target the best answers provided to users, so they are closer to their expectations and personal taste, has become an unavoidable necessity. The collaborative filtering systems are among these information systems with particular characteristics that make the difference. The term refers to collaborative filtering techniques using the familiar tastes of a group of users to predict the unknown preference of a new user. This article describes a basic platform of collaborative filtering, which allows users to discover interesting documents, through automation of the natural process of recommendation, it allows them to express their opinion about the relevance of documents, according to their tastes and documentsâ quality they perceive; it offers the opportunity to benefit from the evaluations on documents of other users, with similar profile, have found interesting. All these benefits are provided to users by the principle of collaboration, in return for an individual effort: evaluating documents.Keywords: Collaborative filtering, community, platform, predictions, recommender system