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Social and Behavioral Sciences Commons

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Civil and Environmental Engineering

Portland State University

Traffic signs and signals -- Control systems

Articles 1 - 4 of 4

Full-Text Articles in Social and Behavioral Sciences

A Simulator-Based Analysis Of Engineering Treatments For Right-Hook Bicycle Crashes At Signalized Intersections, Jennifer Warner, David S. Hurwitz, Christopher M. Monsere, Kayla Fleskes Jul 2017

A Simulator-Based Analysis Of Engineering Treatments For Right-Hook Bicycle Crashes At Signalized Intersections, Jennifer Warner, David S. Hurwitz, Christopher M. Monsere, Kayla Fleskes

Civil and Environmental Engineering Faculty Publications and Presentations

A right-hook crash is a crash between a right-turning motor vehicle and an adjacent through-moving bicycle. At signalized intersections, these crashes can occur during any portion of the green interval when conflicting bicycles and vehicles are moving concurrently. The objective of this research was to evaluate the effectiveness of four types of engineering countermeasures – regulatory signage, intersection pavement marking, smaller curb radius, and protected intersection design – at modifying driver behaviors that are known contributing factors in these crashes. This research focused on right-hook crashes that occur during the latter stage of the circular green indication at signalized intersections …


Avoiding Bus Bunching: From Theory To Practice, Ricardo Giesen Jan 2017

Avoiding Bus Bunching: From Theory To Practice, Ricardo Giesen

PSU Transportation Seminars

The problem of bus bunching in a high frequency service has been largely studied in the literature.

This phenomenon is produced by three main factors

(i) the variability in travel time between stops; (ii) variations in passenger demand; and (iii) drivers’ heterogeneity.

In order to tackle this phenomenon a wide range of control strategies have been proposed, however, none of them had been successfully implemented on a large transit network with high frequency services.

In this talk, we present a control scheme based on a rolling horizon optimization problem that has been successfully implemented for real-time control of two high …


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 …


A Study Of Headway Maintenance For Bus Routes: Causes And Effects Of “Bus Bunching” In Extensive And Congested Service Areas, Miguel A. Figliozzi, Wu-Chi Feng, Gerardo Lafferriere, Wei Feng Jul 2012

A Study Of Headway Maintenance For Bus Routes: Causes And Effects Of “Bus Bunching” In Extensive And Congested Service Areas, Miguel A. Figliozzi, Wu-Chi Feng, Gerardo Lafferriere, Wei Feng

Civil and Environmental Engineering Faculty Publications and Presentations

A healthy and efficient public transit system is indispensable to reduce congestion, emissions, energy consumption, and car dependency in urban areas. The objective of this research is to 1) develop methods to evaluate and visualize bus service reliability for transit agencies in various temporal and spatial aggregation levels; 2) identify the recurrent unreliability trends of bus routes (focusing on high-frequency service periods) and understand their characteristics, causes and effects; and 3) model service times using linear regression models.

This research utilized six months of archived automatic vehicle location (AVL) and automatic passenger count (APC) data from a low-performance route (Route …