中文摘要：

本文以一个制造商、一个零售商和一个第三方回收商组成的闭环供应链系统为研究对象，分析了闭环供应链中存在的“双边际效应”问题，并通过收益费用共享契约解决上述问题，使闭环供应链实现协调。此外，本文分析了突发事件引起闭环供应链中最大市场需求规模发生扰动时，原收益费用共享契约下闭环供应链的协调会被打破这一问题，进而对收益费用共享契约加以改进，使之适用于协调突发事件发生前与发生后的闭环供应链系统。

英文摘要：

The coordinative strategy of closed -loop supply chain consisted of one manufacturer, one retailer, and one third party who is in charge of the recycle of used products is studied. The double marginal effect in closed - loop supply chain is analyzed, and then such supply chain coordinates with revenue - and - expense sharing contract. Furthermore, the conclusion shows that the coordination of the decentralized closed - loop supply chain could be broken off under the original revenue - and - expense sharing contract when the disturbance of the biggest market demand scale in the closed loop supply chain caused by unexpected accident occurs. Then, an improved revenue - and - expense sharing contract has been given, which is able to coordinate the closed loop supply chain and is suitable for coordinating closed loop supply chain before and after unexpected accident.