供应中断情况下的库存控制模型研究

Research on an Inventory Control Model with Supply Disruptions

研究了按单装配系统中一个无时间界限的定期查看库存模型.针对该装配系统中,每个周期的总装配能力有限,产品由不同的组件装配而成,各组件的订货提前期确定,订货提前期的概率分布依赖于外生可观测的马尔可夫链的状态,组件的订货成本是线性的,未能满足的需求全部按照缺货处理,首先提出了一种在给定的状态依赖基础库存策略的情况下,确定长期平均成本的方法,该方法考虑了所有基础库存策略的状态;之后,应用该方法分析了组件中断可能对企业库存状况和长期平均成本带来的影响.研究表明,状态不变的基础库存策略是最优的,并且组件供应中断时间的长短比组件供应中断概率的大小对组件库存策略的影响更大.该研究结果对企业和管理部门中的中断管理以及应急事件计划的制定有一定的参考价值.

We consider an infinite-horizon, periodic-review inventory model in a capacitated assemble to order system in which the products are assembled from some components, and the leadtime probability distribution is dependent on the state of a completely observed, exogenous Markov chain. Order costs are linear, and unsatisfied demand is fully backlogged. In this paper, the author presents a procedure for determining the long-run average cost for a given state-dependent basestock policy. Then these results are applied to analyze the effect of a possible major supply chain disruption on an enterprise＇ s inventory and longrun average cost. Our research shown that the base inventory with constant state is optimal. And the length of components supply disruption has the more effect on the level of components inventory than the probability of components supply disruption. The result can provide some reference for the cooperation between business and government in disruption management and Contingency planning.