Approximations to production lot sizing with machine breakdowns

  title={Approximations to production lot sizing with machine breakdowns},
  author={Kun-Jen Chung},
  journal={Computers & OR},
In general, the study of the convexity (concavity) of the total annual cost function (the annual net pro1t function) should be one of the main research topics about the inventory model. This paper 1rst shows that the long-run average cost function per unit of time for the case of exponential failures is unimodal. However, it is neither convex nor concave. Second, the better lower bound Q∗ ‘ and upper bound Q ∗ u can be obtained to improve some existing results. Finally, numerical examples… CONTINUE READING