CAUSAL FUNCTIONAL REPRESENTATION LANGUAGE WITH BEHAVIOR-BASED SEMANTICS

Understanding the design of a device requires both knowledge of the ge neral physical principles that determine its behavior and knowledge of its intended functions. However; the majority of work in model-based reasoning has focused on using either one of these types of knowledge alone. In order to use both types of knowledge in understanding a devi ce design, one must represent the functional knowledge in such a way t hat it has a clear interpretation in terms of observed behavior. We pr opose a new formalism, causal functional representation language (CFRL ), for representing device functions with well-defined semantics in te rms of behavior CFRL allows the specification of conditions that a beh avior must satisfy, such as occurrence of temporal sequences of events and causal relations among them and the components. We have used CFRL as the basis for a functional verification program, which determines whether a behavior achieves an intended function.