Two-stage metaheuristics algorithm approach to the Location Routing Problem in logistic management

The Location Routing Problem (LRP) is a famous and practical problem in modem Logistic Management. Since the LRP problem includes many candidate facilities and customers with different demands in integrated logistics in studied, it is a combinatorial optimization problem with NP-hard. In original solution of the LRP problem, we usually give fixed assumptions for the modeling; One of the assumptions is there is no traffic jam after we get the optimized routing. However, it is difficult to fulfill this assumption in practice. After being converted to a dynamic optimization problem it becomes a very important problem in real world. In this paper we divide the problem into two sub-problems and then solve them one by one. One sub-problem is deciding which candidate facilities should give service to particular customers on basis of minimum wrap-net method by using heuristic technique. In the second sub-problem, an improved ant algorithm is employed to search for the optimal routes dynamically. The pseudo code is given to the above metaheuristics algorithm as well.