Title

A DYNAMIC SCHEDULE-BASED MODEL FOR CONGESTED TRANSIT NETWORKS

Document Type

Journal Article

Publication Date

2004

Subject Area

operations - capacity, operations - traffic, ridership - commuting, ridership - demand, policy - congestion, mode - mass transit

Keywords

Waiting time, Travel time, Travel models (Travel demand), Travel demand, Travel behavior, Transit traffic, Transit, Traffic congestion, Timetables, Simulation, Schedules, Queuing, Queues, Queueing, Public transit, Origin and destination, O&D, Networks, Network equilibrium, Mathematical models, Mass transit, Local transit, Journey time, Gridlock (Traffic), Equilibrium (Systems), Dynamic traffic assignment, Dynamic models, Computer simulation, Capacity restraint, Algorithms

Abstract

This study describes a model and algorithm for solving the equilibrium assignment problem in a congested, dynamic and schedule-based transit network. It is assumed that the time varying origin-destination trip demand is given. All travelers have full predictive information (that has been gained through past experience) about present and future network conditions. The travelers select paths that minimize a generalized cost function that encompasses four components: in-vehicle time; waiting time; walking time; and a line change penalty. All transit vehicles have a fixed capacity and operate precisely as specified in preset timetables. Passengers queue at platforms according to the single channel first-in-first-out discipline. By using time-increment simulation, the passenger demand is loaded onto the network and the available capacity of each vehicle is updated dynamically. After each simulation run, the passenger arrival and departure profiles at all stations are recorded and these are used to predict dynamic queuing delays. From such delays, minimum paths are updated and used for the next simulation run. The user equilibrium assignment problem is solved iteratively by the method of successive averages. A hypothetical network is used as example to illustrate that the solution algorithm converges to the equilibrium solution in a satisfactory manner.

Comments

Transportation Research Part B Home Page: http://www.sciencedirect.com/science/journal/01912615