Study On Delivery And Pick-up Vehicle Routing Problems In Logistics Distribution

In recent years, logistics, taken as "the third profit resource", has been taken seriously and been developing rapidly. Lots of physical distribution centers are established to improve the efficiency of goods flow by large factories and commercial firms. Meanwhile, considerable sum of transportation corporations, storage enterprises and shipping companies are taking on business of third party logistics. The distribution business is now flourishing in my country. How to low distribution cost is concerned. Transportation is the key part of the logistics distribution, so decline of transportation cost is focused on.Furthermore, to remain invincible in the intense market competition, logistics enterprises are supposed to have their own core strengths and competitiveness. VRP is a crucial and direct link with customs in the entire logistics, whereas, the optimization of vehicle planning of the distribution system is a key segment of the whole optimization system, which directly reflects the nucleus competitiveness of the enterprisesThis dissertation consists of five chapters. Chapter 1 and Chapter 2 are taken as matting for the next chapters, Chapter 3 and Chapter 4 is the key parts and the novelty points. Chapter 5 is about the validation of module.Chapter 1 analyzes the coming into being and developing of logistics distribution and the demand of logistics distribution system in terms of concepts, and introduces VRP. In terms of theories, chapter 2 presents the arithmetic of DPVRP. Then it detailedly classifies and tells reverse logistics that causes DPVRP. Chapter 3 uses transportation informationizing as a clue, explains the structure and functions of the system, formulates the design of database, which includes the basic data structure and electronic map database. At the goal of building module chapter 4 firstly introduces the mixed-integer module to show DPVRPTW, secondly improves C-W saving metricmethod to solve DPVRPTW. Chapter 5 makes use of real cases to validate arithmetic above.Delivery and pick-up vehicle routing problem is complex so we choose saving matrix method ,and improve on it to make sure that we can quickly search the solution of DPVRP with time window.Because of development of logistics distribution and prospect of computer-aided transportation optimization system application, this dissertation gives an assumption to design computer-aided transportation optimization system. And according to some restrictions that maybe occur during real operation of logistics distribution, the author deals with the problem flexibly, and explains the main modules.