Using CSIM to model complex systems

Simulation models of complex systems, defined here to be systems with large number of activities or resources or with activities which exhibit complex behavior patterns, make severe requirements on simulation packages. These requirements are in the form of expressiveness (can you express the complexity in the language of the model?) and in the form of accommodation (can the runtime environment handle the large number of simula- tion objects?). This paper describes CSIM, a process-oriented simulation language based on C, and the features of CSIM which make it useful in developing and executing models of complex systems.