AN INTELLIGENT DATABASE FOR ENGINEERING APPLICATIONS

Many engineering applications need to response to unpredictable events in a timely manner. Active database systems provide an event-driven r ule processing capability to meet this requirement. In this paper, we present an intelligent database which integrates an object-oriented da tabase (OODB) with an expert system, CLIPS. The paper describes the de sign and implementation of the rule manager of this intelligent databa se. In the rule manager, event-condition-action (EGA) rules are repres ented as first class objects of the OODB. A rule definition language ( RDL) has been developed to manipulate ECA rules in a declarative way. A graphical user interface (GUI) also supplies a template to interacti vely define, delete, update and check ECA rules. Detection of time eve nts, method events, absolute events and composite events is supported by the rule manager. The CLIPS inference engine is used to control con dition evaluation and action execution after an ECA rule is triggered. Finally, a typical workflow application is used to illustrate the fun ctionality of the system. (C) 1997 Elsevier Science Limited.