| Since the reform and opening up,our economy has taken off rapidly,and foreign trade has been strengthened constantly.In particular,China joined the WTO,and the economic and trade relationship between China and foreign countries has been strengthened continuously.Since then China has become the leading economic and trade partner in many countries.In this context,container transportation,the most important carrier of foreign trade,continues to develop.However,with the increasing demand for port container transportation,the imperfect operation of container transportation has been fully exposed,the port container circulation is not timely,and the demand information is delayed or wrong,resulting in excessive port operation costs and third-party logistics distribution costs.It is urgent to reduce the cost of port container transportation.The breakthrough point is how to quickly and accurately match the arrival time of container ships with customer demand information,reduce the storage time of goods in the storage yard,speed up the circulation and reduce unnecessary costs.This paper starts from the link between port and logistics company and matches JIT mode to port container transfer link.This paper is based on the "just-in-time,zero-inventory" management principle of JIT(just in time)production mode,and follows its core idea of "appropriate material distribution island at appropriate time".This paper tries to analyze just in time distribution(JITD)of LCL cargo from the perspective of third-party logistics company,set up constraint conditions according to JIT thought,establish port container distribution mathematical model with JIT thought,and select some improved optimization algorithm.Through the simulation software to calculate the mathematical model,get the optimal optimization results.Based on the background of the selected topic,this document is mainly divided into four parts.First,according to the background of the selected topic,the status of research and theories related to just-in-time distribution(JITD),port container and VRPTW(Vehicle Routing Problem with Time Windows)distribution are exposed,and theories related to the distribution are explained.JIT distribution and the distribution of container suitcases.and traditional container distribution The process is analyzed by adding JIT thinking.Second,based on the JIT concept and LCL transportation,analyze the cost components and related constraints,establish a mixed time window penalty cost and customer demand penalty cost mathematical model,and finally establish the LCL freight distribution path optimization model with the optimal objective function cost.Third,through the comparative analysis of various optimization methods,an improved economic-genetic hybrid algorithm is established to promote faster operation and better results.In the design of the algorithm,the elite retention strategy and the adaptive crossover strategy are used,and the improved fitness function is used to search for better optimization capabilities,and the basic genetic algorithm and the improved genetic algorithm are compared through of the algorithm performance test function,and the improved genetic algorithm is obtained.The top skill is stronger and the speed is faster.Finally,the original distribution plan of the case of soybean distribution in port containers was compared with the optimized distribution plan.The optimized distribution cost was lower and the loading rate was higher.The cost was reduced from 1964,138 yuan to 1551,431 yuan,and the charge rate was 79.38% increased to 90.71%.After that,the basic genetic algorithm and the improved genetic algorithm are used to calculate the case.After10 calculations,it is concluded that the improved genetic algorithm has faster convergence speed and stronger stability.. |
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