TREC research addresses complex transportation problems by drawing on multiple disciplines, including engineering, planning, economics and design, from across the Portland State University campus. Use the search box at right to search for a specific project.
Research Highlights
Unsupervised Approach to Investigate Urban Traffic Crashes Based on Crash Unit, Crash Severity, and Manner of Collision
Farzin Maniei Stephen Mattingly
Both crash frequency analysis (CFA) and real-time crash prediction models (RTCPMs) typically divide a highway into segments with a constant length for data aggregation. Despite the significant impact of the segment length in several previous traffic safety studies, no standard approach exists for determining a recommended segment length for crash data aggregation. This research investigates the impact of fragment size (segment length) on traffic crash data aggregation and establishes a…
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Assessing State Efforts to Integrate Transportation, Land Use and Climate Change
Rebecca Lewis Rob Zako
Climate change is increasingly recognized as a threat to life on earth. “Continued emissions of greenhouse gases (GHG) will cause further warming and changes in all components of the climate system. Limiting climate change will require substantial and sustained reductions of GHG emissions.” (IPCC WGI, 2013.)
The transportation sector accounts for almost one-third of all GHG emissions in the United States. Growing Cooler describes GHG emissions from transportation as comprised of a three…
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