Lotfi Bejaoui

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Qualified topological relations between spatial objects with possible vague shape L. Bejaoui abcd; F. Pinet c; Y. Bedard ab; M. Schneider cd a Department of Sciences géomatiques, Laval University, Quebec city, Que., Canada b Industrial Research Chair in Geospatial Databases for Decision Support, Laval University, Quebec city, Que., Canada c(More)
Vagueness is often considered as an inherent property of spatiotemporal phenomena. In order to reduce this vagueness, integrity constraints should be defined to improve logical consistency of spatiotemporal databases. However, existing constraints are not adapted to control logical consistency of vague spatiotemporal objects because they are initially(More)
Topological integrity constraints control the topological properties of spatial objects and the validity of their topological relationships in spatial databases. These constraints can be specified by using formal languages such as the spatial extension of the Object Constraint Language (OCL). Spatial OCL allows the expression of topological constraints(More)
Integrity constraints can control topological relations of objects in spatial databases. These constraints can be modelled using formal languages such as the spatial extension of the Object Constraint Language (Spatial OCL). This language allows the expression of topological integrity constraints involving crisp spatial objects but it does not support(More)
Approaches to make multiple sources interoperable were essentially investigated when one are able to resolve a priori the heterogeneity problems. This requires that a global schema must be elaborated or that mappings between local schemas must be established before any query can be posed. The object of this paper is to study to what extend a mediation(More)
†Centre for Research in Geomatics (CRG), Laval University, Quebec (QC) Canada – lotfi.bejaoui.1@ulaval.ca ‡Industrial Research Chair in Geospatial Databases for Decision Support, Laval University, Quebec (QC), Canada – yvan.bedard@scg.ulaval.ca §Cemagref-Clermont-Ferrand, France – francois.pinet@cemagref.fr ††Dept. Computer Sciences, Blaise-Pascal(More)
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