Study On The Mechanism Of Short Time Passenger Flow Uncertainty For Urban Rail Transit

Short-term passenger flow of urban rail transit is the basis of rail transit operation management and dispatching.Researching the uncertainty mechanism of short-term passenger flow to grasp the dynamic changes is an important way to improve the management level and service level of passengers.In view of the shortage of the current research on the uncertainty mechanism of short-term passenger flow,this paper discusses the formation of short term passenger flow uncertainty from the perspective of individual travel decision.It provides a new way to study the uncertainty of short-term passenger flow.First,the concept of uncertainty of short-term passenger flow is discussed,including the basic meaning of short-term passenger flow,uncertainty theory.And combining the specific situation of the railway transportation system,a clear explanation of the basic characteristics of short-term passenger flow uncertainty is given:random and periodic.Second,the characteristics and related concepts of prospect theory are introduced and the factors of passenger travel decision-making from two aspects of environmental factors and psychological factors are analyzed.And using prospect theory to describe the passenger's decision behavior of the trip mode and departure time,travel decision-making models were established.Combined with the passenger travel decision-making process,there is analysis of the uncertain factors of the various stages about travel information acquisition and decision-making,especially the irrational factors about cognitive limitations and the heuristic cognitive mode in the presence of the passengers cognitive process,which explains the formation mechanism of short-term passenger flow uncertainty in theory.At the same time,this paper analyzes the influence of cognitive uncertainty on travel decision making results.Third,taking the short-term passenger flow history data of Nanjing subway as an example,the uncertainty of different time granularity and different types of short-term passenger flow was analyzed,indicating that the larger the granularity of the time,the lower the uncertainty of the short-term passenger flow.The uncertainty characteristic of short-term passenger flow were analyzed from the aspects of the social environment and the natural environment factors,which showed that the uncertainty of stored-value ticket and single ticket short-term passenger flow in weekend is higher than working days,short-term passenger flows in holidays were higher than that of the adjacent days,and the effects of season weather to short-time passenger flow on flat hump period is higher than the peak period.