Hierarchical Production Control in a Stochastic N-Machine Flowshop with Long-Run Average Cost1

This paper presents an asymptotic analysis of stochastic manufacturing systems consisting of machines in tandem subject to breakdown and repair and facing a constant demand, as the rates of change of the machine states approach infinity.This situation gives rise to a limiting problem in which the stochastic machine availability is replaced by its equilibrium mean availability.The long-run average cost for the original problem converges to the long-run average cost of the limiting problem. A method of “shrinking” and “entire lifting” is introduced in order to construct the near optimal controls for the original problem by using near optimal controls of the limiting problem.The convergence rate of the long-run average cost for the original problem to that of the limiting problem is established.This helps in providing an error estimate for the constructed open-loop asymptotic optimal control