Geographic Information Science: Third International Conference, GI Science 2004 Adelphi, MD, USA, October 20-23, 2004 Proceedings

This section gives a description of notions used throughout this study. Current achievements in developing action—centered ontologies are also discussed. 2.1 Ontologies In the context of information extraction and retrieval, different kinds of ontologies can be distinguished [15]: • Top—level ontologies describe very general concepts like space and time, not depending on a particular domain, • Domain ontologies and task ontologies describe the vocabulary related to a generic domain or kind ...