Proceedings of the 2003 Winter Simulation Conference S. Chick, P. J. Sánchez, D. Ferrin, and D. J. Morrice, eds. A META-THEORETIC APPROACH TO MODELING AND SIMULATION Mamadou K. Traoré LIMOS CNRS UMR 6158 Université Blaise Pascal Campus des Cézeaux 63177 Aubière Cedex, FRANCE ABSTRACT Simulation results Current state Simulator System Objective APPLICATION INTEGRATED COMPUTER-AID DECISION SUPPORT IDENTIFICATION PHASE ENGINEERING PHASE (M&S PROCESS) INTEGRATION PHASE Knowledge extraction scheme Commands Experimental data Validation Problem announcement Problem formulation Conceptual model Verification Verification Specification Knowledge base We aim at building a methodological framework that inte- grates various methods and key concepts in a more coher- ent Modeling and Simulation architecture. The required flexibility for such a framework can be achieved by model- ing the modeling process itself. The essence of this process lies in refining successive abstraction levels, each level into a lower one. The traversal of these abstraction levels, from the highest level (the more abstract) to the lowest one (the more detailed) involves two aspects: (1) System knowledge reside at different levels of a specification hier- archy; (2) many formalisms are often required for knowl- edge specification. As multi-formalism modeling provides a powerful means to deal with many formalisms, we show that modeling in addition the specification hierarchy pro- vides the means to support many modeling processes. Both means are combined in a common meta-theoretic approach to enhance flexibility of the integrative framework. 1 INTRODUCTION As an inter-disciplinary complex problem solving para- digm, Modeling and Simulation (M&S) addresses various applications, leading to diverse methods and underlying concepts. Consequently, it is desirable to integrate these methods and concepts in a coherent methodological framework. The M&S architecture in which our framework is growing is depicted in Figure 1. It attempts to unify ma- jor M&S issues, merging the following key approaches to- gether and with various experiences: • • • The M&S life cycle (Nance 1994). Figure 1: A Unified Architecture for the M&S Life Cycle The synthesis of the relationships between a real system, its conceptual representation and its soft- ware simulator (Zeigler 1976). world system (entities and their relationship, environ- mental constraints, ...) and the objectives of the M&S study (e.g. criteria evaluation, performance optimization, future prediction, ...). This iterative (and sometimes multi- threaded) phase, which is often driven by exchanges be- tween model designers and application domain experts, The analysis of M&S models design and execu- tion (Fishwick 1995). The identification phase, which initiates the M&S life cycle, starts with the announcement of a problem. The problem formulation is the process to identify both the real