Research On Low Carbon Cold Chain Logistics Distribution Logistics Distribution Problem Considering Road Impedance

With the steady improvement of China’s economy,the demand for cold chain food is also increasing.Reasonable arrangement of distribution route is the key content of cold chain food distribution research.Cold chain food mainly includes the following aspects:low-temperature transportation and preservation,food is prone to corruption,transportation is time-effective,and customer points are widely dispersed.The scientific and reasonable optimal distribution route of cold chain food should meet the requirements of customers for time,the lowest degree of corruption of cold chain food,the lowest total distribution cost,the demand of customers and high distribution efficiency.Firstly,this paper summarizes the research results of cold chain logistics,low-carbon logistics and vehicle routing problem at home and abroad,and introduces the concept of cold chain logistics,low-carbon logistics and the elements of vehicle routing problem.The expression form of road impedance is analyzed,the actual driving time of refrigerated vehicle distribution is described by BPR road resistance function,and the road resistance function is improved by replacing the traffic volume in BPR road resistance function with density.Then,the assumptions and constraints of the model are put forward,including vehicle use cost,transportation cost,labor cost,refrigeration cost,cargo damage cost,time cost and carbon emission cost.A low-carbon cold chain logistics distribution path optimization model considering road impedance is established.Finally,in view of the shortcomings of ant colony algorithm and genetic algorithm,the two algorithms are combined,and the former,middle and later methods are used to calculate the pheromone volatilization coefficient ρ Set up a case study of low-carbon cold chain logistics distribution.The results show that the iteration times of genetic algorithm and ant colony algorithm are 23 and 15 generations respectively,and the iteration times of ant colony genetic algorithm is 9 generations,which is significantly better than the other two algorithms.In terms of running time,ant colony genetic algorithm has the shortest running time,18.6 seconds faster than genetic algorithm and 5.6 seconds faster than ant colony algorithm.The distribution costs of genetic algorithm and ant colony algorithm are 7221 and 7576 yuan respectively,and ant colony genetic algorithm is 7187 yuan,The carbon emission cost obtained by ant colony genetic algorithm is lower than that obtained by genetic algorithm,which is 75.26 yuan less than that obtained by ant colony genetic algorithm,and 137.42 yuan less than that obtained by ant colony genetic algorithm.Therefore,the optimal solution can greatly reduce carbon emission.Comparing the three heuristic algorithms with precise enumeration method,the difference between genetic algorithm and accurate enumeration method is 66 yuan,ant colony algorithm and accurate enumeration method is 421 yuan,and ant colony genetic algorithm and enumeration method is 32 yuan,The algorithm designed in this paper is closest to the actual calculated value,and then fully verifies the correctness and effectiveness of the model and algorithm,which is in line with the actual distribution situation of low-carbon cold chain logistics.