ABSTRACT
In order to integrate different geographic data sets a conceptual framework is needed. In this chapter an ontology-based framework will be demonstrated. An ontology is a structured collection of unambiguously defined concepts. There are two kinds of ontologies: (1) ontologies for certain disciplines, domain ontologies, and (2) application ontologies, one for every data set involved. Other components of the framework are sets of surveying rules. Surveying rules determine the transformations from terrain situations into geographic data sets. With the help of application ontologies and surveying rules a top-level domain ontology for topographic mapping is refined and restructured into a reference model, in such a way that this reference model expresses the semantic interconnectedness of data sets. This chapter demonstrates how this refinement and restructuring is done.
