Parallel hybrid models in system design

A parallel hybrid model is a partially implemented design, where some components exist as simulation models and others as operational subsystems, which executes on a parallel architecture. It supports an evolutionary design approach for complex, distributed systems such that an initial simulation model of the proposed design is iteratively refined and elaborated into an implemented system. It also supports hybrid simulation of physical modules and simulation models to facilitate rapid prototyping of complex, distributed systems. The paper describes the use of parallel hybrid models in system design, and discusses their execution issues including cyclic dependency, event causality, and real-time constraints.