中文摘要：

文章研究了易腐品二级供应链中的延迟支付策略问题．对于资金充足和资金受限两种情景，分别给出了没有延迟支付和存在延迟支付时零售商及供应商的利润模型及最优策略，并建立了供应商主导的Stackelberg博弈模型，设计了求解均衡解的粒子群优化算法．最后，通过数值算例探讨了延付期、批发价格及延付利息的变化对零售商和供应商利润的影响，得到了零售商的最优订货策略以及供应商的最优延迟支付决策，对零售商是否接受延迟支付策略进行了权衡分析．结果表明，短期的延付期是可以提高零售商和供应商的利润，但延付期的延长不一定带来零售商利润的提升，同样供应商也无法从零售商手中赚取额外利息利润，反而降低了供应商的利润．另外，资金受限下零售商采用延付通常能够取得更高的收益，同时供应商能够通过提高批发价和利息获得更大利润．

英文摘要：

This paper analyzes permissible delay in payment of a two-level supply chain for deteriorating item considering cash constraint. We obtain the annual profitmodel of supply chain member and the constraint and without cash constraint optimal order policy of the retailer with cash Furthermore, a stackelberg game model be- tween the supplier and the retailer is put forward and a PSO is presented to achieve the optimal solution of the problem. Finally, numerical examples are developed to explore the impacts of some supplier＇s parameters on supply chain members. Out- comes of the paper show that the revenue of the retailer and the supplier increase as the delay period in payment increases before certain threshold point. However, after the threshold, the revenue of them may decrease as the delay period increase. In addition, retailer with cash constrain prefers delay strategy, supplier can also gain more by increasing wholesale price and interest rate.