Abstract: Aiming at the four levels closed-loop supply chain system composed of suppliers, manufacturers, sellers and third-party recycling, the system dynamics method is used to solve the quality control problem of four levels closed-loop supply chain. Firstly, the cause-and-effect loop diagram of four levels closed-loop supply chain quality control is plotted by Vensim simulation software, and the relationship between the influencing factors and the model boundary are found out. Secondly, the equations of each variable are designed, and the system flow diagram and the quality control model of the four levels closed-loop supply chain are further established. Meanwhile, rationality and authenticity of the model are tested. Finally, a numerical example is carried out to verify that the improvement of raw material quality fluctuation level and service quality level can improve the total profit of members at all levels of the four levels closed-loop supply chain, and it also can improve the overall performance of the closed-loop supply chain.

Key words: Four levels closed-loop supply chain, quality control, system dynamics, Vensim simulation

摘要： 针对供应商、制造商、销售商和回收商组成的四级闭环供应链系统，运用系统动力学方法解决四级闭环供应链质量控制问题。首先通过Vensim软件绘制四级闭环供应链质量控制的因果回路图，并分析各影响因素之间的关系及模型边界；其次输入各变量间的方程式，进一步建立四级闭环供应链质量控制的系统流图和模型，并测试模型的合理性和真实性；最后通过数值算例，验证了原材料质量波动水平和服务质量水平的改进可以提升四级闭环供应链各级成员的总利润，同时也能够使闭环供应链整体绩效得以改善。

关键词: 四级闭环供应链, 质量控制, 系统动力学, Vensim仿真