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Full-Text Articles in Engineering
Analysis And Application Of Log-Linear And Quantile Regression Models To Predict Bus Dwell Times, Travis B. Glick, Miguel Figliozzi
Analysis And Application Of Log-Linear And Quantile Regression Models To Predict Bus Dwell Times, Travis B. Glick, Miguel Figliozzi
Civil and Environmental Engineering Faculty Publications and Presentations
Understanding the key factors that contribute to transit travel times and travel time variability is an essential part of transit planning and research. Delay that occurs when buses service bus stops, dwell time, is one of the main sources of travel time variability and has therefore been the subject of ongoing research to identify and quantify its determinants. Previous research has focused on testing new variables using linear regressions that may be added to models to improve predictions. An important assumption of linear regression models used in past research efforts is homoscedasticity or the equal distribution of the residuals across …
Evaluation Of Shared Space To Reduce Traffic Congestion, Kimley Frosch, David Martinelli, Avinash Unnikrishnan
Evaluation Of Shared Space To Reduce Traffic Congestion, Kimley Frosch, David Martinelli, Avinash Unnikrishnan
Civil and Environmental Engineering Faculty Publications and Presentations
Pedestrian and vehicle interactions often lead to conflicts that bring about safety, traffic congestion, and priority or right of way issues. Common methods used in the past to combat said issues have largely relied on the principle of separating the motions of pedestrians and vehicles by means of bridges, tunnels, signals, and access restrictions. A different approach known as shared space aims to solve the same problems with a less structured and defined environment which instead places more reliance on human interaction and perception. Although it has been used in multiple scenarios across Europe with success, instances of shared spaces …
A Study Of Bus High-Resolution Gps Speed Data Accuracy, Miguel Figliozzi, Nicholas B. Stoll
A Study Of Bus High-Resolution Gps Speed Data Accuracy, Miguel Figliozzi, Nicholas B. Stoll
Civil and Environmental Engineering Faculty Publications and Presentations
The recent availability of high-frequency transit (HFT) GPS data for buses has allowed the estimation of detailed bus-travel speed profiles between bus stops. HFT data are defined as data comprising GPS vehicle trajectory recorded at or less than 5 s intervals. With HFT data it is now possible to measure changes in bus speed at specific locations of interest, such as intersections, ramps, crosswalks, and so on. Previous research efforts have not compared GPS-based bus speeds with general traffic speeds at specific locations between stops. This research fills this knowledge gap, utilizing accurate stationary radar speed data as a baseline …
Creating A National Nonmotorized Traffic Count Archive: Process And Progress, Krista Nordback, Kristin A. Tufte, Morgan Harvey, Nathan Mcneil, Elizabeth Stolz, Jolene Liu
Creating A National Nonmotorized Traffic Count Archive: Process And Progress, Krista Nordback, Kristin A. Tufte, Morgan Harvey, Nathan Mcneil, Elizabeth Stolz, Jolene Liu
Civil and Environmental Engineering Faculty Publications and Presentations
Robust bicycle and pedestrian data on a national scale would help promote effective planning and engineering of walking and bicycling facilities, build the evidence-based case for funding such projects, and dispel notions that walking and cycling are not occurring. To organize and promote the collection of nonmotorized traffic data, a team of transportation professionals and computer scientists is creating a national bicycle and pedestrian count archive. This archive will enable data sharing by centralizing continuous and short-duration traffic counts in a publicly available online archive. Although other archives exist, this will be the first archive that will be national in …
Evolution And Usage Of The Portal Data Archive: 10-Year Retrospective, Kristin A. Tufte, Robert Bertini, Morgan Harvey
Evolution And Usage Of The Portal Data Archive: 10-Year Retrospective, Kristin A. Tufte, Robert Bertini, Morgan Harvey
Civil and Environmental Engineering Faculty Publications and Presentations
The Portal transportation data archive (http://portal.its.pdx.edu/) was begun in June 2004 in collaboration with the Oregon Department of Transportation, with a single data source: freeway loop detector data. In 10 years, Portal has grown to contain approximately 3 TB of transportation-related data from a wide variety of systems and sources, including freeway data, arterial signal data, travel times from Bluetooth detection systems, transit data, and bicycle count data. Over its 10-year existence, Portal has expanded both in the type of data that it receives and in the geographic regions from which it gets data. This paper discusses the …
Analysis Of The Impacts Of Transit Signal Priority On Bus Bunching And Performance, Eric Albright, Miguel Andres Figliozzi
Analysis Of The Impacts Of Transit Signal Priority On Bus Bunching And Performance, Eric Albright, Miguel Andres Figliozzi
Civil and Environmental Engineering Faculty Publications and Presentations
Efficient and reliable public transit systems provide opportunities to reduce congestion, emissions in urban areas and provide access and mobility to residents. Headway, or the time difference between departing or arriving vehicles, is a useful measure to gauge bus transit performance; because short headways can lead to bus bunching incidents that quickly degrade transit level of service. While Transit Signal Priority (TSP) has been shown to decrease travel time and delay experienced by buses, little work has shown how TSP may affect bus bunching. This research attempts to understand the characteristics of bus trips, especially TSP, that prevent or promote …