摘要：AbstractWe consider a problem of optimal production and replacement control for a deteriorating manufacturing system containing a single unreliable machine that produces one type of products. The random phenomena are the breakdowns and repairs of the machine, the quality deteriorations and the demand of customers. The machine is subject to deteriorations and minimal repairs, which affect its failure rate and the defective rate of the parts produced, both increasing with the age of the machine. Due to the aging process, the option to replace the machine should be taken to eliminate these effects in order to be able to meet long-term demand. The objective is to find the simultaneous production and replacement control policies in order to minimize the total cost over an infinite planning horizon. The optimality conditions are developed in the form of the second-order Hamilton-Jacobi-Bellman (HJB) due to randomness in demand and quality. Numerical methods are used to obtain the optimal control policies. Finally, to illustrate the contribution of the paper and the robustness of the obtained control policies, a numerical example and a sensitivity analysis are presented.
