High-speed Trains Connection Optimization Of Large Hub Based On Transfers

With the increase of the frequency of personnel flow between major cities in China and the acceleration of the process of high-speed railway network construction,in recent years,China's high-speed rail passenger traffic has grown year by year.However,due to China's vast territory,the layout of large cities is relatively scattered and the distance is relatively long.In addition,due to the daily maintenance distance of the EMU,the difficulty of preparing the cross-line train operation map etc.,the number of direct trains running on medium and long-distance high-speed railways is limited,there are a large number of medium and long-distance cross-line passenger flows in the road network.Some medium and long-distance passengers who choose to travel by high-speed rail can only reach the final destination by transferring within the transit hub.Therefore,research on passenger transfer and optimization issues of medium and long-distance high-speed train connection in high-speed rail hubs is of great significance for ensuring efficient passenger flow transfers and further leveraging the competitive advantages of high-speed rail.This paper summarizes and analyzes the existing literature,and finds that the existing studies on the optimization of train connections in high-speed rail hubs are mostly analyzed from the level of train operation plans and train connection plans,and most of the studies in the literature have not yet considered the issue of passenger transfer at different stations,the acquisition of passenger flow data for demand transfers,and the balance of high-speed train arrivals at interchange hub stations.Based on this,this paper proposes to solve the problem of continuation optimization of medium and long-distance high-speed trains in multiple large-scale high-speed hubs by arranging and optimizing the arrival and departure times of medium and long-distance high-speed trains at interchange hub stations within a certain period.First of all,the overview of large high-speed rail passenger hubs and the theory of medium and long-distance cross-line passenger flow are explained,the advantages and disadvantages and applicability of medium and long-distance cross-line high-speed rail passenger transport modes are comparatively elaborated,and the transfer status of some large high-speed rail passenger hubs in China is analyzed statistically.Furthermore,the passenger transfer process and train connection situation in the high-speed rail passenger hub are studied,the time for passengers to transfer at the same station and transfer at different stations are defined and explained,and the train connection relationship criteria and the classification form of train connection conditions are discussed.Secondly,it is proposed to use the high-speed rail passenger flow statistics algorithm based on the shortest OD distance to obtain the demand-related passenger flow data,with the help of a multi-objective non-linear optimization method,the arrival and departure times of medium and long-distance high-speed trains arriving and departing at high-speed rail interchange hub stations during the study period are used as variables,the optimization objectives are to have the highest average transfer satisfaction for passengers who need to transfer,and the optimal balance of medium and long-distance high-speed trains arrivals and departures on interchange hub routes,comprehensively considers the constraints of station interval time,reasonable train arrival time,and passenger transfer time in the interchange hub,and built a large-scale hub high-speed rail train connection optimization model based on transfers.An improved genetic algorithm is designed for the characteristics of the model,and the coding method of the basic genetic algorithm is improved,at the same time,in the process of designing the selection operator,the strong global search performance of the genetic algorithm is combined with the strong local search performance of the simulated annealing algorithm.Finally,a simplified network diagram of a high-speed railway line in the high-speed railway network and two other lines connected to it is selected as an example,according to the model constructed in this paper and the improved genetic algorithm,the optimization scheme of high-speed rail train connection in the large-scale interchange hub in the example is solved.Comparing the improved genetic algorithm with the basic genetic algorithm,the average transfer satisfaction of objective function one demand transfer passengers increases by 9.59%,objective function two medium and long-distance high-speed trains arrival and departure balance indicators on interchange hub routes increases by 11.70%,this result validates the effectiveness of the model constructed and the improved genetic algorithm designed in this paper.It also shows that the research ideas and methods proposed in this paper can effectively optimize the connection quality of medium and long-diatance high-speed trains in large high-speed railway interchange hubs.This method of arranging and optimizing the arrival and departure times of high-speed trains at interchange hub stations within a certain period can provide effective decision support for the optimization of high-speed train connection in large interchange hubs.