D1.2.4 Inconsistency-tolerant Reasoning with Networked Ontologies

In this deliverable, we discuss the problem of reasoning with inconsistent networked ontologies. We first extend the semantics of description logic ALC with a four-valued semantics. This will allow us to reasoning with inconsistent ontologies non-trivially. We implement an algorithm for reasoning with the four-valued semantics and provide a prototype. We then propose a bilatticebased semantics to generalize the four-valued semantics. We extend OWL2 to bilattice. The bilattice-based semantics can be used to reasoning with trust information and deal with inconsistency. The bilattice-based semantics is applied to a single ontology which is integrated by networked ontologies. Therefore, we propose another approach for reasoning with distributed ontologies which is based on concept forgetting.