摘要:Structured study of spatial objects and their relationships leads to a better cognition of the geospatial information and creates the concept of context at a higher level of abstraction. This study is aimed at providing a comprehensive definition of the context for geospatial objects. A combination of binary qualitative spatial relationships (i.e. direction, distance, and topological relations) among the members of a set of spatial objects will be used accordingly. In addition, by incorporating the general concept of context, obtained from either static data (attributes in a database) or dynamic data (sensors), the compact context of spatial objects will be introduced. Our framework for presentation of the involved knowledge and conception about the objects in context is also explored using ontology and description logic because of powerful conceptualization of relationships, either spatial or non-spatial, integrally. For this purpose, the hierarchies of main structure and object properties are formed at first. The constraint and characteristics of classes, such as subclasses, equivalent classes, cardinality etc., and object properties, such as being functional, transitive, symmetric, asymmetric, inverse functional, disjoint etc., are discovered and presented in more detail using web ontology language in description logic mode. The implementation is then performed in the framework of semantic web and extensible markup language syntaxes. The method ultimately facilitates, spatial reasoning by effective querying in a semantic framework taking pellet reasoner and SPARQL (a recursive acronym for SPARQL Protocol and RDF Query Language).
关键词:spatial objects’ context ; geographic information system ; qualitative spatial relation ; ontology ; description logic ; OWL