"steps to Improve Qualitative Simulation"

This paper reports on two elements of work on qualitative simulation which extend on the basic Qsim algorithm [Kuipers 85] . The work has grown from attempts to examine the limits of current qualitative simulation techniques, specifically a reimplemented Qsim, when applied to models of the heart . The first 'Pragmatics to control simulation' presents ideas which extend the concept of Quality Space which is used in the Qsim system, and argues for a module to control the explosion of state space which occurs when no consideration is given to the meaning of splitting the existing quality space by adding a new landmark . 'Procrastination as a solution to the Qualitative simulation frame problem' presents work on better techniques for navigating the qualitative search space and 'Time to control simulation', reports on work to enhance the basic algorithm by use of temporal information, which is made available as states are generated and by examining previous state chains .