Timetable Optimization For Urban Rail Transit Based On Railway Passenger Hub Station Connecting

Urban rail transit has become the backbone to relieve passengers in railway passenger hub for the large capacity,safety and reliability.Achieving a good connection between the train timetable of urban rail transit and the arrival time of railway trains is an important way to reduce the waiting time of passengers and improve the service level of urban rail transit.It is also a key point to improve the operation efficiency of railway passenger hub.Few studies have considered the impact of impulsive arrival passenger flow at hub stations in the planning stage,and most of them focus on the determination of the equilibrium departure time of trains at the connecting station,as well as ignoring the passenger flow distribution of other stations on the same line.Therefore,based on the basic theory of transportation organization optimization,this study takes the connecting station and line as the research object,and constructs the optimization model of the departure time of the station and timetable of the line allowing for the dynamic passenger flow,which aims to search a new solution for the connection research between urban rail transit and railway.The research details are as follows:Theoretical analysis of timetable scheduling and railway passenger hub connection.First of all,the factors which influencing timetable scheduling are summarized as passenger travel demand,operating conditions and transportation resources.Then,the study makes a detailed analysis of the characteristics of connecting railway passenger hub:Firstly,based on the definition of the spatial transfer mode between railway and urban rail transit,the whole process of transfer is characterized,which lays a foundation for deriving the dynamic passenger flow.Next,the study analyzes the arrival of railway trains and the spatial and temporal distribution characteristics of passenger flow of connecting line.,which reflects the importance of allowing for the railway passenger flow when it comes to timetable optimization.Finally,the framework of train scheduling is proposed.From level of the station,combined with the whole process of railway transfer passengers,the pulsed arrival of the railway passengers is described,which is taken as input of the model of the train departure time,as well as allowing for the uniform arrival of non-railway passengers.The model aims to reduce the total waiting time of passengers and evacuate the passengers in the railway passenger hub as soon as possible.From level of the connecting line,focusing on the passenger distribution of the connecting station,while considering that of other ordinary stations on the connecting urban rail lines and putting a certain penalty on the passenger detention time into the objective function,the model of timetable scheduling is established to determine the departure time at the first station of each train by the unbalanced mode.Which aiming at minimizing the total passenger waiting time of the whole line.Finally,combined with the characteristics of the problem,an improved nonlinear adaptive genetic algorithm is designed based on the traditional genetic algorithm.Case studies and results analysis.Based on the actual data of Shenyang Metro Line 1 connecting Shenyang Railway Station,the test schemes are designed for the station level model and the line level model respectively,and solved by the designed algorithm.Furthermore,combined with the visualization method,the total waiting time of passengers,the number of passengers remaining,the full-load rate of trains and the number of people gathered at the connecting stations are taken as evaluation indicators and compared with the initial scheme to verify the validity of the model.The sensitivity analysis of the model is further studied by discussing number of trains and the weight of the connecting station.It is found that the model proposed in this paper is more effective in the off-peak period of the urban rail transit rather than peak period.The reason lies in the fact that the connecting station has the largest proportion of passengers in the whole line during the off-peak time,and the train departure interval is more sufficient to optimize.Focusing on the distribution of passenger flow at the connecting station is conducive to improving the level of urban rail transit service,but it will sacrifice the passenger travel efficiency of the ordinary station at the same time,thus affecting the service level of the whole line.In actual operation,the relationship between the two should be correctly handled in combination with different scenarios aiming to optimize the comprehensive service level of urban rail transit.