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Social and Behavioral Sciences Commons

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Portland State University

Engineering

Intelligent transportation systems

Articles 1 - 4 of 4

Full-Text Articles in Social and Behavioral Sciences

Modeling And Analyzing The Impact Of Advanced Technologies On Transit Performance Measures In Arterial Corridors, Miguel A. Figliozzi, Wei Feng Aug 2014

Modeling And Analyzing The Impact Of Advanced Technologies On Transit Performance Measures In Arterial Corridors, Miguel A. Figliozzi, Wei Feng

Civil and Environmental Engineering Faculty Publications and Presentations

Transportation and transit agencies have implemented advanced technologies like transit signal priority (TSP) and Sydney Coordinated Adaptive Traffic System (SCATS) to reduce travel times and improve reliability. However, due to the lack of detailed empirical data, the joint impact of these factors and improvement strategies on bus travel time has not been studied at the stop-to-stop segment level. With the aim of assessing the performance of an existing TSP/SCATS system, this study had access to a unique set of high-resolution bus and traffic signal data. Novel algorithms and performance measures to measure TSP performance are proposed. Results indicate that a …


Characteristics Of Transitions In Freeway Traffic, Robert L. Bertini, Soyoung Ahn Sep 2010

Characteristics Of Transitions In Freeway Traffic, Robert L. Bertini, Soyoung Ahn

Civil and Environmental Engineering Faculty Publications and Presentations

This research seeks to understand the characteristics of transitions as freeway traffic changes from one state to another. This study addresses the features of two types of transitions; transitions near a merge and transitions along shock waves during the onsets and dissipations of queues at several freeway sites.

Individual vehicle trajectory data were analyzed for studying the transitions near a merge. The length of a transition zone was measured by analyzing the spatial changes in flow, density and speed along kinematic waves near a merge. It was found that the length of transition in terms of flow, density and speed …


How Can We Best Manage Freeway Congestion?, Robert Bertini, Christopher Monsere Dec 2008

How Can We Best Manage Freeway Congestion?, Robert Bertini, Christopher Monsere

TREC Project Briefs

Researchers from Portland State University evaluate Oregon’s Implementation of System-Wide Adaptive Ramp Metering (SWARM).


Using Archived Its Data To Measure The Operational Benefits Of A System-Wide Adaptive Ramp Metering System, Robert L. Bertini, Christopher Monsere, Oren Eshel, Soyoung Ahn Dec 2008

Using Archived Its Data To Measure The Operational Benefits Of A System-Wide Adaptive Ramp Metering System, Robert L. Bertini, Christopher Monsere, Oren Eshel, Soyoung Ahn

Civil and Environmental Engineering Faculty Publications and Presentations

A System-Wide Adaptive Ramp Metering (SWARM) system has been implemented in the Portland, Oregon metropolitan area, replacing the previous pre-timed ramp-metering system that had been in operation since 1981. SWARM has been deployed on six major corridors and operates during the morning and afternoon peak hours. This report presents results of a "before" and "after" evaluation of the performance of two freeway corridors as part of ongoing efforts to measure the benefits of the new SWARM system, as compared to the pre-timed system. The study benefited from using the existing regional data, surveillance and communications infrastructure in addition to a …