Expressive Multi-level Modeling for the Semantic Web

In several subject domains, classes themselves may be subject to categorization, resulting in classes of classes (or "metaclasses"). When representing these domains, one needs to capture not only entities of different classification levels, but also their (intricate) relations. We observe that this is challenging in current Semantic Web languages, as there is little support to guide the modeler in producing correct multi-level ontologies, especially because of the nuances in the constraints that apply to entities of different classification levels and their relations. In order to address these representation challenges, we propose a vocabulary that can be used as a basis for multi-level ontologies in OWL along with a number of integrity constraints to prevent the construction of inconsistent models. In this process we employ an axiomatic theory called MLT (a Multi-Level Modeling Theory).