Issues in the pragmatics of qualitative modeling: lessons learned from a xerographics project
The photocopier is one of the most complex machines because xerography involves many types of physical phenomena. ARIA is a qualitative simulation of xerography that is intended to teach technicians the reasons behind some of the subtle problems that occur in copiers. This effort to model xerography exposed shortcomings in the techniques of qualitative modeling as applied to complex systems and helped to better understand the impact of certain basic modeling decisions.