Research On The Closed-loop Supply Chains Management

In this dissertation,the importance of the Closed-loop supply chain management and the sate of art of the field reviewed.The characters of Closed-loop supply chain management are analyzed and some problems existed in the field are studied.This dissertation has mainly carried on the following research.A mathematical model and an algorithm for the location problem in closed-loop supply chain are proposed.There are forward logistics and reverse logistics in the closed-loop supply chain.These two kinds of logistics share the same supply chain networks in the model and the quantities of requirement and reverse products are considered stochastic.Variable neighborhood search algorithm is designed for the location problem in closed-loop supply chain.Multiple solutions are used in parallel in the algorithm,and the solutions are modified in an evolutionary manner during the algorithm running.Location routing problem in closed-loop supply chain problem is also studied and the mathematical model is put forward.The problem combines location problem with vehicle routing problem.All of these problems are hard combinatorial optimization problems.This kind of problem is solved by stages usually.The stages include location and location routing respectively.A genetic algorithm is designed to solve the problem and location and routing are tackled simultaneously in the genetic algorithm by the solution coding and evolution.Performance measurement is also studied which is important in closed-loop supply chain management.The index system of closed-loop supply chain performance measurement is proposed in this dissertation.The index system is hierarchical which consists of key enterprise(supplier) performance,distributor performance,retailer performance and the integrated performance.The indexes include economic performance measurements in usual meaning and the social performance measurements especially in closed-loop supply chain.The indexes are also can be considered as qualitative and quantitative.The performance measurement problem is a kind of comprehensive evaluation problem and a modified analytic hierarchy process combined genetic algorithm is proposed.Closed-loop supply chain management is a kind of complex system analyzing problem.So the closed-loop supply chain management system based on multi-agent system is designed.Agents in the system are established according to the structure entity and function entity,and the system built with the agents is the same hierarchical as the closed-loop supply chain.In order to improve the communicating effectiveness between agents and the system effectiveness,an expended contract net protocol is proposed which is named multi-step protocol based on constraints relax.