Qualitative modeling with temporal causality network and quantity network

A qualitative reasoning scheme with explicit temporal expression is presented. Its aim is to develop a possible solution for the fundamental problem of temporal reasoning and ambiguity rather than to refine the existing techniques for a specific domain. The proposed system represents the system behavior in the form of a partially ordered network. Time intervals may be defined in terms of relative lengths in a quantity space. Such explicit description of temporal quantities helps reduce ambiguity in qualitative simulation. An independent quantity space management system organizes the qualitative reasoning about physical and temporal quantities.<>