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Broad boundaries are generally used to represent objects with fuzzy spatial extents. This concept is typically defined as a polygonal zone that should respect both connectedness and closeness conditions. Therefore, some real configurations, like regions with a partially broad boundary (e.g., a lake with rocker and swamp banks), are considered invalid. The(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)
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)
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