Control of Raw Materials Releasing for a Manufacturing System with Product Quality Downgrade

In some manufacturing systems, when raw materials of higher quality product are released into the system, the quality of a small part of finished goods is likely to be downgraded because of some random factors like machine failure. To improve the service level of products with different quality levels and minimize the average production cost, the releasing of raw materials for products with various quality levels should be well controlled. In this research, we construct the mathematical model of raw materials releasing control problem for manufacturing systems with quality downgrade. A hedging point control policy is proposed for this problem, and the structural characteristics of this policy are revealed by solving the linear programming problem. The control policy can drive the system state to the hedging point effectively. Furthermore, numerical experiments are conducted to evaluate the performance of the proposed policy and the impact of the hedging point on the average production cost.