Ontology aware software service agents: meeting ordinary user needs on the semantic web

To achieve the dream of the semantic web, it must be possible for ordinary users to invoke services. It is clear that users need simple-to-invoke-and-use services. This dissertation offers an ontological approach to declaratively create services that users can invoke using free-form, natural-language-like specifications. Our approach uses task ontologies as foundational knowledge. A task ontology consists of a domain ontology and a process ontology. The domain ontology encodes domain information such as possible constraints and instances in terms of object sets, relationship sets among these object sets, and operations over values in object sets and relationship sets. The process ontology consists of generic processes that are domain independent-coded once and work for all. Our system recognizes the constraints in a service request, discovers any missing information and obtains it from users, and formalizes the constraints in the context of the domain ontology. The system satisfies the constraints by obtaining information from databases associated with the domain ontology and providing users with solutions or near solutions when there is no way to satisfy all the constraints. Our experiments with our prototype implementation show that our approach can create services that satisfy end-user needs.