考虑成品质量差异和失销的混合系统库存决策

Inventory Decision-making for a Hybrid System Considering Quality Differences and Lost Sales of Finished Items

为确定最优的制造与再制造策略,对制造新品和再制造品存在质量差异并分别在一二级市场进行销售的混合系统进行研究。从一二级市场收购的旧产品再制造后仅用于满足二级市场的顾客需求,以最小化单位时间总成本为目标,建立了两类决策模型:1 1个制造周期N个再制造周期模型;2 M个制造周期1个再制造周期模型。运用消元法减化模型和利用差分函数对模型求解,得到了相关决策变量的求解公式。分析表明,单位制造新品与再制造品的生产成本和失销成本、单位旧产品的收购成本不会对制造与再制造决策产生影响。随着一、二级市场旧产品买回比率的提高,生产商倾向于采用1个制造周期N个再制造周期安排制造与再制造业务,其生产成本进一步降低。

To determine the optimal manufacture and remanufacture policy, a hybrid system is investigated in which newly manufactured and remanufactured items have different quality and are sold in primary markets and secondary markets respectively. Used items bought back from primary and secondary markets are remanufactured only to fulfill the demand of customers in secondary markets and two types of decision-making models are formulated to aim at the minimum unit time total cost： （1）one manufacturing cycle and N remanufacturing cycle model, （2）M manufacturing cycle and one remanufacturing cycle model. The models are reduced by the elimination method and solved by the difference function, and the formulae on related decision variables are derived. The analysis shows that unit lost demand cost and unit production cost for a newly manufactured item or remanufaetured one and unit buyback cost for used products have no impact on the decision-making for manufacturing and remanufacturing. With the increase of buyback rate for used products from primary and secondary markets, the producer tends to adopt one manufacturing cycle and N remanufacturing cycle method to arrange the manufacturing and remanufacturing operations and his production cost will be reduced further.