An exact discrete-event model and control policies for production lines with buffers

The authors present a hybrid simulation/analytic model for the analysis and design of unreliable production lines with buffers and discrete workparts. The model is exact and much faster than conventional piece-by-piece simulators. It can analyze, efficiently and accurately, lines of any size during either transient or steady-state periods by taking into account effectively all transients associated with the function of the line. It is demonstrated that the model is superior to both brute-force and event-driven models and is an efficient practical tool in the analysis and design of production lines. By incorporating the perturbation analysis technique into the proposed algorithm. the gradient estimation of the system´s throughput can be performed during a single simulation run for various design parameters. A number of experimental results are reported for the repair allocation problem, and the optimality of various control policies is investigated