Out-of-order execution and structural equivalence of simulation models

This paper revisits a technique for determining structural equivalence between simulation models. Specifically brought under scrutiny are the restrictions for applying a rule that expands a compound event vertex when converting a simulation graph model (SGM) into an extended SGM. By checking for interdependencies of state variables within the vertex, one can ensure that the logical structure of the original model is preserved during expansion, allowing for “out-of-order” execution of events - thus permitting a greater class of models to be deemed structurally (and behaviorally) equivalent. An example is provided of establishing structural equivalence between two discrete event simulations derived from the same model, which benefits from the revised expansion rule.