Representing Discrete Events in System Dynamics Models: A Theoretical Application to Modelling Coal Production

The paper begins with the suggestion that simulation modelling has traditionally been divided into two separate types-open-loop discrete-event based analysis and closed-loop continuous modelling. Separate simulation packages have been evolved for meeting these needs.There are, however, important managerial problems where the discrete and feedback processes are both present and are both significant, and they pose a modelling dilemma. It is shown that the dilemma can be resolved, without the use of hybrid languages, by using the random processes and very flexible logical operator facilities in DYSMAP in a novel way to create discrete events. This is demonstrated by a theoretical application within the coal mining industry.