Executive Summary

The aim of this deliverable is to present a framework for representing the interrelationships between distributed ontologies within a heterogeneous ontology network and dealing with mismatching or even conflicting concept definitions. For this purpose, we take advantage of related efforts within the SEKT and Knowledge Web projects. We employ a mapping language which we developed in a joint effort with the SEKT project to describe the connection between ontologies. Such a mapping language allows us to deal with complementary concept definitions. Our approach to reason with the ontology network starts with importing the ontologies into a common format that eliminates the heterogeneity. We consider WSML Flight as an appropriate language for the common format because it shows an optimal trade-off between expressivity and tractability. After translating the ontologies into WSML Flight, we define mappings based on the mapping language defined in a joint effort with the SEKT project. Afterwards we insert the parts of the ontologies and the mappings that are relevant to the query into a so-called reasoning space. We detect the parts of the ontologies and the mappings that are relevant to the query by means of