Research On Optimization Algorithms For Vehicle Routing Problem With Weight-Related Cost And Inventory-Transportation Problem In Distribution System

The economic development impels the process of the globalization of the manufacturing enterprises. The competition among enterprises has become the competition among the supply chain which the enterprises belong to. The level of supply chain management determines the competitiveness of the supply chain. How to manage and optimize the supply chain effectively becomes a hot issue concerned by the managers of the enterprises. The distribution system meets customers' needs to complete the conversion from product to merchandise. It is an important part to increase the value of the supply chain and it is a bridge between producers and consumers. The inventory and transportation costs in the distribution system account for a relatively high proportion of the logistics costs. The effective management and optimization of the distribution system is the key of the supply chain management. Hence, the optimization problems in the distribution system become a focus of the theoretical study. However, the distribution system is a complex system, and there are many factors to be considered in the optimization and not to be ignored simply. At the same time, the new management and operation continue emerging to make the existing research and decision not be applied to the new environment and condition, which leads to the demand about the decision and optimization on the distribution system under the new environment or operation being urgent increasingly.For this reason, the production and distribution enterprises are as the background. The vehicle routing decision with weight-related cost and the integrated inventory transportation problem under vehicle-rent operation mode are considered systematically by adopting the theory and method of the optimization. The major work of this paper includes five aspects as follows:(1) Based on the routing problem and integrated inventory and transportstion problems, the summary and the corresponding research are done from the aspects of the modeling and solution. The different classification methods, the basic extensions of the vehicle routing problem and the different modeling methods are presented. The two types of integrated inventory and distribution problems classified by the different research focus are introduced. The solving algorithms of the vehicle routing problem and the integrated inventory and distribution problem are studied. The above-mentioned work provides a theoretical and methodological support for the research of the key issues.(2) The detailed description of the background of the vehicle routing problem with weight-ralated cost (VRPWRC) has been given. The model of the weighted traveling salesman problem is presented. Two types of methods are introduced to solve the problem. One type is to modify the solutions of the Traveling Salesman Problem which are CW algorithm and a kind of particle swarm optimization algorithm. The other is to design a heuristic by considering the characteristic of the problem. The reason of studying the problem is given. The scatter search algorithm for the vehicle routing problem with weight-related cost is proposed. The heuristic rule considering the weight-related cost is embedded in the framework of scatter search algorithm. The comparison with other algorithms for the same problem is to verify the validity of the scatter searcfi algorithm. The applicability of the model is analyzed.(3) Based on the vehicle routing problem with weight-ralated cost, the multi-depot vehicle routing problem with weight-ralated cost is proposed that the depot of the VRPWRC is extended from one to multiple and the constraint of the route length is considered. To solve the problem, the solving algorithm of the multi-depot vehicle routing problem is studied first. The benchmark problems of the multi-depot vehicle routing problem are used to test the scatter search algorithm and to verify the validity of the algorithm. Considering the scatter search algorithms for the multi-depot vehicle routing problem and for the VRPWRC, the scatter search for the multi-depot vehicle routing problem with weight-ralated cost is proposed. The effect of varying the parameter of weight-related cost on the total cost and the applicability of the model are analyzed. The performance of the proposed algorithm is also studied.(4) The integrated inventory and transportation problem with different operation mode of transportation is studied. It focuses on comparing and analyzing the difference adopting the different operation mode of transportation for the same problem. The applicability of the different operation mode of transportation under the different conditions is obtained by analyzing the total cost of the different operation of transportation with the same plan, the relationship among the optimal solutions of the different operation mode of transportation and the effect of varying the parameters on the total cost under vehicle-rent operation mode. The factors that affect the selection of the operation mode of transportation are presented. The method of the measurement is introduced to guide the enterprises to select the operation mode of transportation.(5) The multi-period integrated inventory transportation problem with the vehicle-rent operation mode and the many-many network structure is considered in production and distribution enterprise. Based on the observation to the new operation mode of transportation, the inventory and multi-depot open transportation problem with vehicle-rent (IMDOT-VR) is proposed. The transportation part is modeled by the open vehicle routing problem. A genetic algorithm with elitist preservation strategy is developed for IMDOT-VR. The solution is coded by two-dimensional coding. The initial population is generated by the heuristic rule. The mutation operator is designed to reduce the inventory and penalty cost. The random data is used to verify the effectiveness of the algorithm.