| In recent years,the demand for intra city freight transportation in China is increasing.Urban online truck-hailing has developed rapidly Since its emergence because of its convenience and timeliness.Vehicle routing problem(VRP)is the vital branch of logistics distribution system research,it is very important to reduce the cost of logistics distribution.Compared with the traditional vehicle routing problem,the vehicle routing problem of online truck-hailing is more complex.Its main characteristics are the randomness of order generation time and delivery point location,uncertainty of service time,time window constraint and dynamic distribution demand.In this paper,based on the analysis of the existing research on vehicle routing problem,the vehicle routing problem of urban online truck-hailing is studied by adding feature constraints.This paper summarizes and reviews the research status of vehicle routing problem at home and abroad,focusing on the analysis of dynamic vehicle routing problem with uncertain demand problem,urban logistics distribution and online car hailing,and introduces the development status of urban online truck-hailing and Policy environment,and analyzes the characteristics of online truck-hailing distribution.Then the fundamental theory,classification and Main solution methods of vehicle routing problem are elaborated in detail,and each influencing factor of vehicle routing problem is analyzed emphatically.Then,combined with the characteristics of vehicle routing problem in freight network,the paper analyzes the components of vehicle routing problem of online truck-hailing,transforms the time window constraint into time penalty cost to show customer satisfaction,divides the distribution cost into vehicle fixed use cost and variable cost,and establishes single vehicle model and multi vehicle model with the minimum total distribution cost as the objective functionIn the process of solving the problem,it is necessary to continuously plan the optimal distribution route of new orders and calculate the corresponding distribution cost.This paper designs a genetic algorithm which can effectively solve the distribution route optimization of random new orders in small and medium-sized network.Two different examples are set to verify the effectiveness of the algorithm for solving the model,and the different results of single vehicle and considering different vehicle distribution in the same network scale are analyzed.The results show that the genetic algorithm has better performance for the small-scale distribution network.The results show that the Genetic Algorithm has good performance for the small-scale distribution network.Conclusively,the model is used in the goods distribution in Anning District of Lanzhou City as a case study.Anning District is selected as the optimization scope,and a distribution network is built between 28 places with dense flow of people,with each place corresponding to a delivery node,and the two hours between 15:00 and 17:00 are selected as the research time scope for experimental Calculation. |
