Research On The Path Optimization Of Express Vehicles With Hard Time Window

With the development of The Times and the progress of the society,the happiness index of people’s life is gradually rising,and the way of shopping is also gradually developing.By 2022,China’s online retail sales have reached 13.79 trillion yuan,which brings the development of the express industry.Due to the economy and timeliness of the express industry,more and more express enterprises begin to pay attention to the transportation problem of express delivery.How to reduce the distribution cost,improve the timeliness of delivery and express delivery,and the reasonable arrangement of the transportation path of express delivery vehicles has become a key issue for the development of express delivery enterprises.Based on this problem,this candidate has the express vehicle path optimization research with a hard time window as the research object of the master’s thesis.The specific research contents are as follows:Firstly,the research status of vehicle routing problems at home and abroad is expounded,and according to the characteristics of the logistics and transportation industry and the existing distribution mode,the optimization problem of express delivery vehicles in self-operated post stations studied in this paper is introduced.And considering that exceeding the customer’s time window will receive customer complaints and thus affect the revenue of the station,so a mathematical model of vehicle distribution with a hard time window is designed,and when designing the objective function of the mathematical model,the objective function is divided into two sections,namely the cost of using the vehicle and the delivery cost of the vehicle,and the objective function is the minimum that is,the total cost of distribution is the minimum as the optimization goal under reasonable constraints and appropriate assumptions.Secondly,the implementation process of ant colony algorithm and genetic algorithm on this problem is designed,and the shortcomings of the existing genetic algorithm are found under the verification of Solomon example,the large-scale neighborhood search algorithm is combined with the genetic algorithm,the hybrid genetic algorithm is designed,and the large-scale neighborhood algorithm is used to insert the local search operation of the genetic algorithm,so that the search ability of the mixed genetic algorithm is improved and the effectiveness of understanding is strengthened,and the Solomon study is used again.The feasibility and effectiveness of hybrid genetic algorithm in solving the delivery route optimization problem of express vehicles are verified.Finally,taking L express station in Changchun city as an example,combining ant colony algorithm and mixed genetic algorithm,MATLAB software was used to solve the actual situation of L express station respectively,and compare the distribution cost of the two After comparison,it is found that the hybrid genetic algorithm can reduce the transportation cost and improve the timeliness of express delivery in practice.It makes the express vehicle path optimization research more practical significanceThe optimization model of express vehicle path of L express delivery station in Changchun city is representative to a certain extent,and this modeling can be also applied to the solution of express delivery stations under the same self-operated mode.It is expected that this paper can provide some theoretical reference for the distribution methods of these post stations.