考虑学习效应的可复用物流容器供应链的最优运作决策研究

本文研究了单个制造商通过可复用物流容器将产品送至单个零售商的闭环供应链,在可复用物流容器回收处理后得到的数量小于发出时数量的条件下,本文考虑可以通过工人操作过程中存在的学习效应来降低可复用物流容器的丢弃率。本文构建了两个模型：模型1未考虑维修中心工人操作过程中存在的学习效应,可复用容器的丢弃率为随机变量;模型2考虑维修中心工人在操作过程中存在学习效应,使得可复用物流容器的丢弃率不断降低。通过定量分析确定了最小联合库存总成本下的最优运行周期、货物配送次数以及可复用容器配送次数。结果表明,在任一供应链参与者不采取降本措施的情况下,仅考虑工人在操作过程中存在的学习效应就可以起到降低容器丢弃率、节约总成本的效果。此外,本文还分析了制造商可以支付给工人的最大维修费用,为企业的成本投入预算提供决策依据。     

On bivariate ageing properties of exchangeable Farlie–Gumbel–Morgenstern distributions

This paper deals with bivariate Farlie–Gumbel–Morgenstern distributions. We build the TP2 (RR2) property of the residual lifetime and study the evolution of the dependence of the residual lifetime at large age. Also, we derive the aging property in the sense of the upper orthant order. Furthermore, in the context of IFR (DFR) marginals the residual lifetime at the age above the median is found to be increasing (decreasing) in the upper orthant order.     

A closed-loop supply chain for deteriorating products under stochastic container return times

This paper studies a two-stage supply chain where returnable transport items (RTIs) are used to ship finished products from the supplier to the buyer. Empty RTIs are collected at the buyer and returned to the supplier. The return time of RTIs is considered to be stochastic in this paper, and further finished products are assumed to deteriorate during potential delivery delays. First, the paper develops an analytical model of this supply chain, and then it discusses the properties of the model. Secondly, it presents the results of a simulation study in which the behaviour of the model is analysed. The results of our analysis indicate that the supply chain can influence both the risk of RTI stockouts at the supplier and the deterioration rate by changing the value of the return lot size of RTIs. Further, the results indicate that realising the optimal value for the RTI return lot size is especially important in case the mean return time of RTIs is short, while in case of a long RTI return lead time, an approximation of the optimal RTI return lot size is also acceptable.