新旧产品品质持续下降的库存管理策略分析

Optimal Inventory Policy for New and Recovery Items with Time-Declining Value

回收品品质下降是一个客观事实;企业利用回收品时,为了保证整机产品可靠性以及最小的成本支付,迫切需要在订货策略和旧产品剔除时机等多方面进行决策.贵金属催化剂,因为自然衰减原因,即使不投入冶炼,其产品活性也逐渐降低;因此,催化剂的库存管理更为棘手.以化工行业钯铑等贵金属催化剂为例,针对催化剂活性因为自然衰减和中毒衰减而持续下降的事实,以系统醛含量建立Markov过程,获得了企业订货策略和旧产品剔除的优解.研究表明,品质下降产品的回收再用过程中,(s,Q)订货策略优于(s,S)订货策略;而且,企业确实存在一个可以兼顾成本支付以及旧产品风险的旧产品剔除阈值.

Normally, the quality of recovery items will decline, and the quality of precious metal catalysts will decline even when they are new. For a better reliability assurance and lower cost expenditure, enterprises are eagerly seeking an optimal policy on acquisition and disposal. This paper observes the character- istics of natural decay and poisoned decay for the aldehyde activity of precious metal catalysts, establishes the Markov process of aldehyde in the system and, then, obtains the optimal safe inventory of aldehyde, acquisition quantity and disposal threshold. This study proves that the （s,Q） acquisition policy is superior to the （s,S） acquisition policy and that there exists a suitable disposal threshold for the recovery items.