| Under the Belt and Road Initiative,the China-Europe Railway Express has achieved "full results".As a result,it has already radiated 28 countries and more than 60 cities in Europe in recent years,opened a new chapter of Eurasian railway transportation and became a bridge between the two countries.The CR Express has advantages such as short distance,quick aging,high security and all day long segmented transportation.Under the situation of large scale stagnation of international air and sea routes caused by the outbreak of Covid-19 pneumonia,the CR Express kept smooth and became a priority for the transportation in the opposite direction.It showed strong vitality during the epidemic.However,while the CR Express has made remarkable achievements,it also faces many problems that hinder its development,such as unclear market positioning,insufficient supporting facilities,high repetition of lines and insufficient supply of goods,which will increase the cost of the train,damage its operation efficiency and stability,and is not conducive to the formation of real market competitiveness.Therefore,based on the overall perspective,this text constructs a hybrid hub and spoke logistics network model for the CR Express to allow direct transportation,and the overall route layout of the CR Express can be optimized,so as to promote the high-quality development of it.The main research contents include the following aspects:The first part is current situation of the CR Express operation and its two logistics transportation modes,point-to-point transportation and assembly center transfer,compares and summarizes the current problems of the CR Express logistics transportation network.Then it combs the specific classification and characteristics of the hub-and-spoke network theory system,and paves the way for the following determination of the basic research carrier for the optimization of the CR Express transport network based on the hub and spoke theory.Secondly,construct a hybrid hub-and-spoke logistics transportation network model allowing direct transportation.The model takes the minimization of network operation cost as the objective function,adopts the hybrid two-stage algorithm of random search-Genetic Algorithm,and solves the model through Python programming.After,collect the relevant data of the CR Express for empirical research,the result shows that the system cost is the best while choosing five cities of Tianjin,Zhengzhou,Chongqing,Xi’an and Suzhou as the hub nodes.The total cost of the hybrid hub and spoke logistics transportation network model with direct access is about 20.19% lower than that without direct access,which shows that the establishment of direct transportation in the network can reduce the transportation cost and improve logistics efficiency,on the basis of this,study the factorial experiment of the number p of central hubs and the discount coefficient of trunk transportation α.Finally,combined with the research conclusions of this paper,four suggestions are put forward to promote the development of the CR Express.To sum up,the CR Express logistics transportation network which combines centralized and point-to-point direct transportation,not only improves the efficiency of transportation scale,but also reduces the detour cost.Thus,the operation efficiency of the train is improved,which can provide a reference for the optimization of the CR Express logistics transport network transportation in the future. |
