Optimal and near-optimal policies for lost sales inventory models with at most one replenishment order outstanding
- 作者：Roger M. Hill and Sø ; ren Glud Johansen
- 关键词：Inventory ; Lost sales ; Semi-Markov decision processes ; Policy iteration
- 刊名：European Journal of Operational Research
- 出版年：2006
- 期刊代码：58_03772217
- 类别：et
- 出版时间：2006
- 卷：169
- 期：1
- 页码：111-132
- 文件大小：406 K
摘要
In this paper we use policy-iteration to explore the behaviour of optimal control policies for lost sales inventory models with the constraint that not more than one replenishment order may be outstanding at any time. Continuous and periodic review, fixed and variable lead times, replenishment order sizes which are constrained to be an integral multiple of some fixed unit of transfer and service level constraint models are all considered. Demand is discrete and, for continuous review, assumed to derive from a compound Poisson process. It is demonstrated that, in general, neither the best (s, S) nor the best (r, Q) policy is optimal but that the best policy from within those classes will have a cost which is generally close to that of the optimal policy obtained by policy iteration. Finally, near-optimal computationally-efficient control procedures for finding (s, S) and (r, Q) policies are proposed and their performance illustrated.