Research On Logistics Distribution Routing Problem Based On Improved Ant Colony Algorithm

Distribution plays an important role in logistic system, and it requires delivering the right commodities to the right place by the right method at the right time. Vehicle routing problem (VRP) involves the design of a set of minimum-cost vehicle routes, delivering the right commodities to the right location by the very method at the very time. So vehicle routing problem represents a very important part of any logistic distribution systems and they are named as one of the most successful areas in Operations Research in the past decades. So it becomes an important studying trend to solve the vehicle scheduling problem with heuristic algorithm.In this dissertation, the main research work and innovative points for vehicle routing problem as follows: We firstly describe the development history and research situation of the VRP, and then present the mathematical model and the constraint conditions of the problem. Meanwhile, we give a review of the past research on vehicle routing problems and their solution methods, establishing the base of algorithm in this dissertation. On the base of reality, we purpose the researchproblem——vehicle routing problem with time window (VRPTW) and construct amathematical model. The model has the vehicle capacity and customer demands as constraint conditions, and the distribution cost as the objective function.Ant Colony Optimization (ACO) algorithm is a new swarm intelligence heuristic algorithm. Owing to its positive feedback and effective parallelization and strong lustiness, ACO has been applied in many fields. However, the traditional algorithms have the problems of early convergence or stagnation in the process of combinatorial optimization problems. To solve these problems, this dissertation proposes three novel improved ant colony algorithms of solving the VRPTW problem. Through the analysis of the principle of ACO, the improved ACO algorithms were realized by object-oriented thought. The test results of a series of Benchmark problems indicated that the improved ACO algorithms were efficient in solving VRPTW problem, especially in the large-scale VRPTW problem.Finally, the most important creative point is that by the background of "The critical technologies and platform of modern logistics management", develop the VRP Optimizer, which is a software toolkit developed by FLTK and Visual C++ 6.0. In the system, some common optimization algorithms, the ACO and three improved ant colony algorithms are adopted to solve the VRPTW test cases, and then compare the different results, in the end, choose the best solution. This software has improved the efficiency of distribution, optimized the management and obtained preferable effect in factual application.The conclusion of this dissertation has significance of realistic theory and application value to the establishment of logistics distribution and vehicle routing problem, and it is valuable for the study of ant colony algorithm.