An ontology-based method for quality assesment of spatial data bases
Résumé
We propose an ontological approach for the quality assessment of spatial databases. This process is carried out at two levels. At the ontological level, the internal consistency of the specifications is considered. At the data level, real objects and their relations are studied with respect to the specifications. For this purpose, the national topographic database of Canada is selected as the case study. The ontology of the spatial database is translated into a knowledge base coded in Prolog. Then rules that define inconsistencies were defined. The querying of the knowledge base to determine the existence of such inconsistencies was carried out on a very large fact base. By this process, spatial relation between each pair of objects is analyzed with respect to the permitted relation between such objects in the ontology. The results obtained from various experimentations indicate the presence of several inconsistencies in the analyzed data set. These problems were attributed firstly to the control system that oversees the production process and secondly to the incomplete ontology. The overall approach appeared to be justified. The results obtained from several experimentation illustrated the potential of the proposed method for the quality assessment of spatial data bases in both ontological and data levels.