Study On Urban Rail Transit Train Operation Plan Model Considering Stop-skip And Coordinated Synchronizaion

Congestion of urban traffic makes an influence on the daily travel quality of individuals and reducing their efficiency of necessary trips.At the same time,it can also cause social problems,such as traffic safety and environmental pollution.Based on the large capacity,fast,safe,high efficiency,energy saving and environmental protection advantages,urban rail transit(URT)has become the main way to relieve the pressure of urban traffic as the transit skeleton of a city.With the continuous development of urban rail transit network construction,operation management strategy,measures and methods have entered the phase of network operation from a single line operation.Then,traditional and onefold operation plan has been more and more difficult to satisfy the demand of large scale and complexity of network passenger.In this inevitable trend,accurate,efficient and quantitative evaluation of train operation plan modeling theoretical system needs to be established.This system is supposed to be a theoretical approach of forecasting,planning and preparating for operations management department.Moreover,it provides technical guidance and evaluation methods to adjust and optimize the existing timetabling.As a result,it is going to improve the level of service(LOS)of the URT in order to realize the harmonious development of urban transit and passenger travel.Based on the compilation principle,theory and method of the URT operation scheme,our study analyzes the interaction mechanism between network,trains and passenger demands.The stop-choice problem,control of departure and arrival,the plan of buffer times and the headway is researched.The operation scheme is discussed considering the stopping times,the behaviors of transfer passengers,the arrival pattern and the buffer times.From the perspective of satisfying the demand of passenger demands and controlling the operational efficiency,multi-scenarios of modeling theoretical system is established considering passenger travel cost and operation cost.It could provide the adjusting method and the quantitative evaluation index for designing the stop,seamless transfers and robustness optimization.At first,the references of operation scheme,timetabling and robustness research are reviewed.The modeling ideas and algorithm of existing references aiming at frequency,turning-around,stopping,LOS of passengers,waiting times,transfer efficiency and robustness are analyzed.The methodology of URT operation scheme study is summarized in detail.The core of our study is stop-skipping,synchronization and coordination of transfer,the robustness of timetabling.The main objective and research area of establishing modeling theoretical system of operation scheme is proposed.Then,the optimization problem of URT stop-skipping plan is studied on the single line.Passengers’ waiting time,travelling time and trains’ cycle time are calculated accurately.Based on the constraints of trains’ departure and arrival,a model is established with the goal of minimization of passengers’ travel cost and company’s operation cost.A bi-objective nonlinear mixed integer programming model with 0/1 decision variable is proposed.With ideal point method applied,the bi-objective function is transformed into a single objective one remaining the constraints unchanged.A large scale calculation problem is solved by tabu algorithm.Based on four representative demand distribution scenarios,the availability of the model is verified.Five current stop-skipping plans are compared and analyzed due to the stochastic demands.According to an empirical operation plan of foreign URT,operation schemes combination of several train are exacted.Based on the given passenger demands,the operation benefits of the local train,the rapid train and the express train combinations are compared.Further,the above-mentioned analysis is used to illustrate the different effects of the deterministic and stochastic operation schemes.Based on the five representational case of different demand assignment,applicable conditions are analyzed with satisfying various demands.With the departure time of the first train determined concisely,a model aiming at the maximization of the number of successful transfer is proposed in order to achieve synchronization and coordination at the network.Then the genetic algorithm(GA)is designed to solve this model.Due to the comparative optimization before and after,as well as the results form the CPLEX solver,the improved GA is proven to be feasible and effective to solve it.Moreover,the synchronized and coordinated optimization model was put forward,which was based on accurate division of passengers of urban rail transit.Its target is to achieve the seamless transfer for the passengers.The corresponding normal distributions of transfer arrivals are established according to different transfer stations.To minimize the total transfer waiting times was set as the target of the model.The constraints of trains running,passenger division and the calculation method of waiting times are input.The model was a non-liner planning model with binary decision variables.The model was solved by combining improved genetic algorithm with computer simulation.At last,the robust timetabling optimization model for URT is proposed based on passenger demands.Based on the interaction between waiting passengers and trains,the actual dwell time of trains is calculated,which is compared with the planed dwell time to judge whether the train is delayed or not.If it is delayed,the buffer time need to be adjusted by means of our proposed model.Using these measures,it can improve the robustness of timetabling and avoid increasing the extra timetabling cycle.The objective of the model was to minimize the deviation time of timetabling.The nonlinear mixed-integral programming model was established and solved by the improved genetic algorithm.