Research On The Optimization Of City Distribution Routes Considering Time Dependent Road Networks

The logistics and transportation industry is a basic industry supporting the development of national economy,an important support for building a modernized economic system and promoting high-quality economic development,and city distribution plays a crucial role as the "last mile" of logistics and transportation.The optimization of the city distribution path and the improvement of logistics transportation efficiency and service level are the keys to enhance the core competitiveness of logistics enterprises.Enterprises,customers and distributors are important subjects in the logistics and transportation system,and only by taking into account the interests and demands of all subjects can logistics enterprises obtain a win-win situation in terms of economic and social benefits.Based on this,this paper takes city logistics distribution as the research object,considers the time-varying traffic road network and customer’s pickup demand,and takes the carbon emission cost into account in the total cost of distribution,and investigates the Time Dependent Green Vehicle Routing Problem with Simultaneous Pickup and Delivery(TDGVRPSPD)in city distribution mode.The main research work of this paper is as follows:(1)The VRP-Model of Comprehensive Aversion(VRP-MCA)is constructed for city delivery.First,based on the "First-In-First-Out" criterion,the time-dependent road network characteristics are analyzed,and the distribution time is divided into several time periods,and the vehicle travel time calculation methods for different time periods are expressed by segmentation functions.Second,aversion is used to describe the degree of interest and demand satisfaction of the three subjects: enterprise,customer,and distributor.The deviation of total cost from the minimum ideal value is taken as the measure of enterprise aversion,the deviation of the time window of the distributor to reach the customer is taken as the measure of customer aversion,and the proportion of the distributor ’s waiting time in his total working time is taken as the measure of delivery agent aversion,and the weight coefficients are introduced to integrate the three and establish a path-optimized comprehensive aversion model.(2)Design an Improved Aquila Optimizer Based on Adaptive Large Neighborhood Search(IAO-ALNS)strategy.Based on the discrete optimization features of VRP,the Aquila-Customer(A-C)coding and decoding strategy is proposed to redefine the intelligent search behavior of Aquila by combining the four ways of hunting prey: expanded exploration,narrowed exploration,expanded exploitation and narrowed exploitation.The adaptive large-scale neighborhood search strategy is introduced,multiple neighborhood destruction operators and repair operators are designed,and an inferior solution acceptance criterion is added to the algorithm,and two stagnation perturbation strategies,the circular heuristic perturbation mechanism and the elite solution perturbation mechanism,are proposed.The effectiveness of the IAO-ALNS proposed in this paper is verified by the Solomon benchmark experiments and the comparison experiments based on the TDVRP test case with the Iterative Route Construction and Improvement algorithm(IRCI),Genetic Algorithm(GA),Particle Swarm Optimization(PSO)and Ant Colony Optimization(ACO).(3)The validity of the model and algorithm is verified through case experiments.Based on the actual geographic location and time-varying road network information,simulation experiments are conducted with Datong D enterprise as the research object to compare and analyze the models with different optimization objectives.The experimental results show that VRP-MCA can better balance the customers and distributors while optimizing the total cost of distribution.By analyzing the trends of total vehicle distribution cost under different time-varying road networks and vehicle models,it is concluded that logistics enterprises should consider the influence of time-varying road networks when planning distribution solutions,and reasonably plan the distribution time and choose distribution models according to the size of customers and the actual service demand,while the government should formulate relevant policies to alleviate traffic congestion,reduce road transportation costs,and help realize the optimization of the "last mile" of city distribution.The research on TDGVRPSPD model and solution algorithm in the city distribution mode has enriched the theoretical basis in the field of city logistics distribution and vehicle routing problems.At the same time,the research results have certain guiding significance for the planning of city distribution scheme and vehicle scheduling decision of logistics enterprises,and play a role in promoting the high-quality development of logistics industry.