The Optimization Of Common Delivery Routes Of Fresh Agricultural Products Cold Chain Logistics

In recent years,the cold chain logistics industry has become increasingly prosperous in China.This not only expands the scope of business in the logistics industry in China,but also stimulates the development of fresh foods.Some fresh supermarkets such as Yiguo and Freshhema have begun to flourish.Even e-commerce companies such as TMall,JD,and SUNING also launched fresh food platforms and distribution services.However,the scale of fresh food enterprises in China is not large enough.They are relatively fragmented,they cannot form market competitiveness,and there are some problems in site selection and distribution.Therefore,this thesis takes the fresh agricultural products with large demand of urban residents as the research object,responds to the development concept of national shared economy and green logistics,adopts the common distribution model,and reasonably plans the development pattern and cold chain distribution route of fresh agricultural products within the city.This dissertation summarizes China’s development plans and policies for agricultural products,cold chain logistics services,and joint distribution models,and analyzes the development status of the three aspects,sums up domestic and foreign experts and scholars in these aspects,as well as various types of intelligent heuristic algorithms,especially the use of simulated annealing algorithm to solve the vehicle routing problem.When referring to the research results of other scholars,it is found that there are problems such as the fixed the coefficient of the cargo damage cost,the single product type,and the use of simulation data in these studies.Combining these issues,this dissertation uses fresh produce as the research object,obtains relevant sample data and adopts a common distribution model to create a model for the path optimization of cold chain logistics.This thesis sorts out the conceptual model of common distribution,the classification of the vehicle routing problem and the original mathematical model,the elements of the simulated annealing algorithm,the flow,the characteristics,and other theoretical knowledge.It elaborates on the eight basic elements of the model,including customers,cold chain distribution vehicles,and objective functions,etc.Based on these elements,a six-part framework model consisting of farms and farmers,fresh produce providers,farmers’ markets(distribution centers),customers,third-party cold chain logistics companies and information platform(e-commerce platform)was established.Combined with previous research results,a new mathematical model for the common distribution route of cold-chain logistics for fresh agricultural products is established.At the same time,this dissertation also specifically describes the various costs incurred when a cold chain delivery vehicle completes a distribution activity.The linear reduction formula of the allocation loss ratio is added to the cargo damage cost,and a variety of fresh agricultural products are distributed.After the model is created,the simulated annealing algorithm is mainly used to solve the optimization mathematical model of the common distribution route of fresh agricultural products cold-chain logistics.Using MATLAB 2015 b software,30 communities in Kunming are randomly selected as distribution sites,three sets of experiments were conducted including simulated annealing algorithm for solving 13 distribution points,particle swarm algorithm for solving 13 distribution points and simulated annealing algorithm for solving 30 distribution points.Comparing the three groups of experimental results,it is found that the simulated annealing algorithm is superior to the particle swarm algorithm regardless of computational efficiency or accuracy when solving vehicle path problems.And the simulated annealing algorithm is also suitable for solving large-scale vehicle routing problems.Although the accuracy is reduced,it can quickly obtain the result close to the optimal solution.Finally,this dissertation puts forward some ideas on the future development path of the common distribution route of fresh agricultural product cold-chain logistics.For example,the dynamic vehicle route problem can be used,the actual traffic situation can be considered,and a better algorithm can be used to solve the model.Simultaneously,it is expected that the research in this dissertation will provide some help for the development of cold chain logistics in China in fresh agricultural products.