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Tri-County Metropolitan Transportation District of Oregon, Transportation -- Oregon -- Portland -- Planning, Intelligent transportation systems, Transportation -- Data processing

Physical Description

1 online resource (34 p.)


An operations plan contains information on the provision of transit service, including intended service levels, vehicle availability, and driver schedules. Agency resources would be utilized efficiently if the operations plan could be executed without disruptions in service. When service disruptions occur, the aim of operations control is to optimize system performance given the current state of the system (Wilson et al., 1992). This typically involves actions intended to either return service to schedule or restore headways separating vehicles. Disruptions in service impose costs on transit providers in the form of reduced productivity and on passengers in the form of increased in-vehicle travel time, longer waiting time at stops, and greater uncertainty.

This paper has two overall purposes. First, it provides a review of operations control principles and practices reported in the literature. Second, it reports the results of an operations control experiment whose objective was to maintain headways, or the time separation between buses on a route. The experiment was developed to explore a possible application of the automated Bus Dispatching System (BDS) recently implemented by Tri-Met, the transit provider for the Portland, Oregon, metropolitan region.


Catalog Number PR117.

Published by the Center for Urban Studies, College of Urban and Public Affairs, Portland State University.

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