In the classical inventory systems, the retailer had to settle the accounts of the purchased items at the time they were received. But in practice, the supplier applies some strategic tools, such as trade credit contract, to enhance his sales channel and offers delay period to his customers to settle the account. Any member of the supply chain may offer full or partial trade credit contract to his downstream level. Full trade credit is the case that the latter is allowed to defer the whole payment to the end of the credit period. In partial trade credit, however, the downstream supply chain member must pay for a proportion of the purchased goods at first and can delay paying for the rest until the end of the credit period. This paper considers a two-level trade credit, where the supplier offers order-quantity-dependent partial trade credit to a retailer, who suggests full trade credit to his customers. An economic order quantity (EOQ) inventory model of a deteriorating item is formulated here, and the Branch and Reduce Optimization Navigator is applied to find the optimal replenishment policy. The sensitivity of the variables on different parameters has been analyzed by applying some numerical examples. The data reveal that increasing the credit periods of the retailer and the customers can decrease and increase the retailer’s total cost, respectively.

中文翻译：

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上游部分订单-数量相关贸易信贷和下游全额贸易信贷下的EOQ模型中变质项目的订购策略

在传统的库存系统中，零售商必须在收到购买的物品时结清帐款。但是在实践中，供应商运用一些战略工具（例如贸易信贷合同）来扩大其销售渠道，并为客户提供延迟结算账目的期限。供应链的任何成员都可以向其下游级别提供全部或部分贸易信贷合同。完全贸易信贷是允许后者将全部付款推迟到信贷期末的情况。但是，在部分贸易信贷中，下游供应链成员必须首先支付一定比例的已购买商品，并且可以将其余货款的支付延迟至信贷期结束之前。本文考虑了两级贸易信用，供应商向零售商提供与订单数量有关的部分贸易信贷，零售商向其客户建议全部贸易信贷。在此制定了变质项目的经济订单数量（EOQ）库存模型，并应用“分支和减少优化”导航器来找到最佳补货策略。通过应用一些数值示例，分析了变量对不同参数的敏感性。数据显示，增加零售商和客户的信用期可以分别减少和增加零售商的总成本。通过应用一些数值示例，分析了变量对不同参数的敏感性。数据显示，增加零售商和客户的信用期可以分别减少和增加零售商的总成本。通过应用一些数值示例，分析了变量对不同参数的敏感性。数据显示，增加零售商和客户的信用期可以分别减少和增加零售商的总成本。