Study On Passenger Flow Assignment Method Of Urban Rail Transit Based On Improved Logit Model

In the backdrop of urban rail transit network operation,the number of urban rail transit passengers is steep rise and network structure is increasingly complex.The expansion of the urban rail transit network increased the diversity and randomness of passenger route choice,and enhancement the uncertainty and dynamic of urban rail transit network passenger flow distribution.This brings great challenges to the operation and management of urban rail transit.Therefore,it is necessary to model and analyze the passenger travel behavior in theory and calculate the passenger flow distribution accurately,and provide reliable theoretical foundation and technical means for the safe operation of urban rail transit.In this paper,Space L method is used to construct the underlying network model based on the physical network of urban rail transit,then transfer stations and terminal stations are extracted from the underlying network to establish the upper network directed graph model.The K short path algorithm is used to search the effective path in the upper network,and then the effective path set of the upper network is mapped to the underlying network by the association transfer station set.So,the effective path set of the whole network is solved by this means,and the search efficiency is improved.According to the survey of passenger travel behavior of urban rail transit,the main influencing factors of passenger travel are analyzed,and angular cost is introduced to indicate the role of route information in the map guiding passengers travel.The generalized cost function of passenger travel is defined to quantify the utility value of passenger travel path by considering the in-train time,waiting time,transfer cost,congestion cost and angular cost.Aiming at the defects of the Multinational Logit Model,the utility value of the path is adjusted by the path size in the utility function,the selection probability is calculated by the relative cost of the path,and the improved Logit model is proposed to improve the accuracy of passenger flow assignment.Take the Beijing rail transit network in 2016 as an example,the upper and underlying network model are build,and the OD passenger flow matrix is extracted from the cleaned AFC data.MATLAB software is used to program passenger flow assignment model based on path size Logit,and obtaining the results:operation indicators of lines,passenger flow distribution,section load,transfer passenger flow and so on.This verify the validity and applicability of the passenger flow assignment model.Finally,based on the research results of this dissertation,the Beijing rail transit passenger flow simulation system is developed,which provides a decision support platform for urban rail transit passenger flow monitoring and the mining of passenger flow distribution law.