HCCM - A Control World View For Health Care Discrete Event Simulation

The classical world-views of discrete event simulation (DES) are event scheduling, activity scanning and process interaction. A fourth approach, the three-phase method, extends activity scanning and is often regarded as another world-view. These world-views provide the theoretical framework for applying DES in practice. However, in health care simulation, practitioners often face modeling challenges where the concepts and methodologies described by these world-views are not able to reflect either the dynamics or the entity flow of the system being modelled. This leads to individualized approaches and solutions that do not build on a unified and standardized theoretical basis. In this paper we present an extension to the activity scanning world-view based on the needs of the health care sector that uses hierarchical control structures as a more general, flexible and powerful tool to define health care DES models. To demonstrate the strength and potential of the approach two ongoing simulation studies are briefly outlined and the benefits of using the new world-view for these models is discussed. INTRODUCTION AND MOTIVATION In DES the underlying system is changed at discrete points in time. How these changes are modeled, controlled and triggered is dependent on the sub-domain of discrete event simulation, also known as the worldview, being utilized. The classical world-views are: event scheduling; activity scanning; and process interaction. However, the three phase method, which is an extension to the activity scanning approach, is also often referred to as a world-view. Much work has been done to formalize, evaluate, compare and transform the different world-views, as in (Balci 1988; Birta and Arbez 2007), or more recently (Overstreet and Nance