Structuring and querying personalized audio using ontologies

User-customized information selection and delivery reduces the complexity of the overwhelming amount of information available to end-users. Our approach employs user profiles, data selection, and presentation facilities to deliver customized audio information to end-users. Specifically, we construct a domain-dependent ontology (a collection of key concepts and their inter-relationships) to enable user-profile construction to support the retrieval of personalized audio information. In this research, we show how a domain-dependent ontology facilitates the generation of metadata. We demonstrate that ontology provides end-users richer forms of information to query into the system rather than keyword search. We present how this ontology is used to generate information selection requests (database queries in SQL). We develop an efficient algorithm for conjunctive queries in client-server architecture. Finally, we discuss novel optimization techniques that improve query processing performance, utilizing the knowledge associated with the ontology. The approach we have developed is being implemented in the context of the Personal AudioCast project at the USC, Integrated Media Systems Center.