Qualitative modeling techniques for process control and diagnosis

Qualitative reasoning is an alternative to mathematical modeling and can be used to reason about unforeseen situations that are not encoded in the knowledge base. The authors focus on the constraint-based approach to qualitative reasoning using an algorithm called qualitative simulations (QSIM). They explain the basic concepts of QSIM using a simplified pulp bleaching example. Further on, they discuss how this can be used to do fault diagnosis.