Qualitative Spatial Reasoning in RCC8 with OWL and SWRL

The Region Connection Calculus (RCC), and particularly its RCC8 subset, have been extensively studied and used for qualitative spatial reasoning. Some sets of computational operations have also been defined for topological relations, as the CM8 set, that allows to compute the RCC8 relationships on raster images. In this paper, we propose a reified representation of the RCC8 spatial relationships and of the CM8 primitives, within a lattice of concepts, implemented in OWL (Ontology Web Language) in order to help the interpretation of urban satellite images. Our approach allows for a straightforward representation of concepts corresponding to conjuctions or disjunctions of RCC8 spatial relationships, and thus offers the advantage to overcome some drawbacks of the existing approaches in OWL, where spatial relations are represented as roles. Indeed, the OWL language does not allow the expression of the disjunction or of the conjunction of roles. We can then implement a reasoning on the RCC8 relationships, which in particular allows to compute the composition table and its transitive closure. As the reification of roles precludes the use of role's properties, such as symmetry and transitivity, we propose to implement RCC8 inferences through SWRL rules (Semantic Web Rule Language).