Exploiting Shared Ontology with Default Information for Web Agents

When different agents communicate with each other, there needs to be some way to ensure that the meaning of what one agent embodies is accurately conveyed to another agent. It has been argued that ontologies play a key role in communication among different agents. However, in some situations, because there exist terminological heterogeneities and incompleteness of pieces of information among ontologies used by different agents, communication among agents will be very complex and difficult to tackle. In this paper, we proposed a solution to the problem for these situations. We used distributed description logic to model the mappings between ontologies used by different agents and further make a default extension to the DDL for default reasoning. Then, base on the default extension of the DDL model, a complete information query can be reduced to checking default satisfiability of the complex concept corresponding to the query.