Quality control in manufacturing systems using M/G/1 queues with (N+1) different inspection rates

In this paper the authors propose a model with (N+1) different inspection rates which can be integrated with a manufacturing process described by an M/G/1 queueing system. Using illustrative examples, based on hypothetical data, the model is used to investigate the optimal inspection strategies under two, three and four inspection rate policies. For any value of N it is possible to achieve equality optimal inspection strategies by carefully selecting the associated inspection rates for different ranges of queue lengths (work in process).