Stéphane Bressan

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The <italic>Context Interchange strategy</italic> presents a novel perspective for mediated data access in which semantic conflicts among heterogeneous systems are not identified a priori, but are detected and reconciled by a <italic>context mediator</italic> through comparison of <italic>contexts axioms</italic> corresponding to the systems engaged in data(More)
If XML is to play the critical role of the lingua franca for Internet data interchange that many predict, it is necessary to start designing and adopting benchmarks allowing the comparative performance analy sis of the tools being developed and proposed. The effectiveness of existing XML query languages has been studied by many who focused on the comparison(More)
In this paper, we propose a new tunable index scheme, called iMinMax(<italic>&Ogr;</italic>), that maps points in high dimensional spaces to single dimension values determined by their maximum or minimum values among all dimensions. By varying the tuning &#8220;knob&#8221; <italic>&Ogr;</italic>, we can obtain different family of iMinMax structures that are(More)
Some XML query processors operate on an internal representation of XML documents and can leverage neither the XML storage structure nor the possible access methods dedicated to this storage structure. Such query processors are often used in organizations that usually process transient XML documents received from other organizations. In this paper, we(More)
Efficient spatial joins are pivotal for many applications and particularly important for geographical information systems or for the simulation sciences where scientists work with spatial models. Past research has primarily focused on disk-based spatial joins; efficient in-memory approaches, however, are important for two reasons: a) main memory has grown(More)
The emergence of the Internet as the de facto Global Information Infrastructure enables the construction of decision support systems that leverage on the panoply of on-line information sources. This highly dynamic environment presents a critical need for a exible and scalable strategy for integrating the disparate information sources while respecting their(More)
The Context Interchange Project is studying the semantic integration of disparate, i.e. distributed and heterogeneous, information sources. In this paper, we illustrate the principle of Context Mediation using examples from an application of our prototype. We outline the Context Mediation abductive framework and present the Context Mediation procedure. We(More)
The success of the World Wide Web measured in terms of the number of its users and of the resulting traffic increase is only commensurate to the patience required when sitting in front of one’s computer, waiting for a document to be down-loaded. If one could identify the typical access patterns for a set of documents on a Web server, the server could use or(More)