Research On Site Selection Of Collection And Delivery Points And Vehicle Routing Optimization For Urban Fruits And Vegetables Distribution

With the improvement of people's living standard,the concept of healthy diet has become increasingly popular.The annual output of fresh fruits and vegetables in China was huge and increasing year by year,and fresh fruits and vegetables have become an indispensable food in people's daily life.In the selection of fresh fruits and vegetables,consumers have also paid more and more attention to quality issues such as freshness and nutritional value of fruits and vegetables.However,the development of cold chain logistics in China started relatively late.Compared with western developed countries,fresh agricultural products in China still had a higher rate of decay and a lower circulation rate.In the process of distribution of fresh fruits and vegetables in China,the cold chain was often broken,so the research on the distribution of fresh fruits and vegetables could effectively reduce the problem of fruit and vegetables corruption caused by improper distribution,so as to ensure the safety of fresh fruits and vegetables.This paper has taken urban fresh fruit and vegetable distribution as the research object,and adopted the collection and delivery points distribution mode to complete the last kilometer distribution task of urban fresh fruit and vegetable.This paper mainly studied the location problem of collection and delivery points and vehicle routing problem for urban fresh fruit and vegetable distribution.In terms of collection and delivery points location,the location selection has been combined with the daily travel laws of residents,and the mean shift clustering algorithm has been used to perform data analysis and information mining on the daily travel data of residents to complete the collection and delivery points location;In tenns of route optimization of distribution vehicles,the vehicle route optimization from distribution center to centralized delivery point was completed by establishing the mathematical model of route optimization of fresh fruit and vegetable distribution vehicles and solving it with particle swarm optimization algorithm.Finally,the visual module of distribution vehicle information has been designed to realize the visual management of distribution vehicle.Firstly,taking the convenience and coverage of collection and delivery points as the main factors,a method of site selection of collection and delivery points based on residents' daily travel rules has been proposed.The data of the origin and destination points of residents' daily trips were used as sample data to carry out mean shift clustering analysis,and the high-frequency visiting areas of residents' daily trips were obtained.Concentrated at the same time in order to meet the delivery point for residential area coverage,for each sample data given to determine weight value and weight value contained by the sample data under the specified radius and the number of residential,contains the more the number of residential weight value,the greater the makes different sample data's contribution to the final location point was different,made it more tend to residential areas,to ensure the location points of residential area coverage.The validity of the method was verified by comparing the site selection results with the distribution of cainiao post station.Secondly,combined with collection and delivery points distribution mode and adopted by the city of fresh fruit and vegetable distribution characteristics of city fruit and vegetable distribution costs was analyzed,the summation of the fixed cost,transportation cost,refrigeration and violation of time windows penalty cost as the optimization goal,to distribution vehicle maximum load ability as the main constraint condition,city fresh fruits and vegetables distribution route optimization model has been established.The particle swarm optimization(pso)algorithm was designed to solve the model,and the superiority of pso in solving the model was verified by comparing with genetic algorithm.Finally,at present there were few specific logistics link design vehicle information visualization module,in order to facilitate the delivery vehicles to realize visualization management and ensure distribution process transparent,designd the distribution vehicle information visualization management module,project of distribution vehicle location and distribution of visual representation,but also realized the distribution of data statistical analysis and management.