Research On Distribution Route Optimization Of Cold Chain Logistics Considering Dynamic Demand

With the acceleration of urbanization and the upgrading of consumption level of residents,the market demand of cold chain food such as fresh fruits and vegetables is increasing rapidly,which makes the cold chain logistics industry enter a period of rapid development.However,in the cold chain logistics distribution,the unreasonable path planning leads to high distribution cost and low resource utilization,which seriously restricts the overall development level of the cold chain industry.At the same time,the emergence of fresh e-commerce and delivery platforms has brought great convenience to consumers in the way of shopping,making consumer demand more dynamic and diversified,this further increases the difficulty of cold chain logistics path planning.Therefore,in the cold chain logistics distribution problem,considering the customer’s dynamic demand,how to carry on the path optimization,is the current cold chain logistics domain urgent need to solve the problem.Firstly,based on the theories of cold chain logistics and dynamic vehicle routing problem,the characteristics of the problem are analyzed,the types of the problem are defined,a two-stage solution method of static planning followed by dynamic adjustment is proposed,the composition of the total cost of cold chain logistics distribution is discussed,and the calculation method of each cost is determined.The specific costs include vehicle start-up costs,fuel consumption costs,damage costs,refrigeration costs,carbon emission costs and penalty costs for violating the time window.Secondly,the dynamic vehicle routing optimization model of the cold chain logistics is constructed to minimize the total cost of distribution.For the dynamic information processing,two processing strategies,dynamic batch optimization and real-time re-optimization of urgent orders,are proposed,the two-stage solution flow chart is refined.According to the characteristics of the problem,particle swarm optimization algorithm is chosen as the solution algorithm,considering that the diversity of particles decreases quickly and the premature convergence is easy to occur,an improved particle swarm optimization based on 2-opt~*and relocate is proposed,and the validity of the algorithm is verified by the test of a standard example.Finally,YZ cold chain logistics enterprises as an example of case analysis,with the help of MATLAB software to obtain the optimal distribution path.By comparing the static and dynamic two-stage test results,the cold chain logistics distribution optimization scheme considering the dynamic demand can effectively improve the utilization ratio of vehicles,save the distribution time and reduce the distribution cost,it has more application value and can provide practical and feasible decision-making reference for cold chain logistics enterprises in distribution scheme.