A pattern based approach of integrating data and knowledge to support cooperative query answering

A framework for integrating class-oriented data grouping and subject-oriented knowledge grouping to support cooperative query answering is proposed. This framework is characterized by a three layer data/knowledge organization: object layer, object-subject layer, and subject layer, where a database at the object layer and a knowledge base at the subject layer are coupled by virtual database patterns specified at the object-subject layer. Based on such an architecture, communicating databases and knowledge bases are organized and maintained independently but linked dynamically under specific subjects. Cooperative query answering can then be accomplished through tracing the behavior dependencies amongst cooperating objects under those subjects. To implement this approach, mechanisms of dynamic-classifications, deductions, focus transitions and goal rewrites are introduced. An experimental cooperative database system, CoBase, was developed to demonstrate the effectiveness of the approach