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
Does Compact Development Increase or Reduce Traffic Congestion?
Reid Ewing Shima Hamidi
It is now widely held, even among many state transportation departments, that you cannot “pave your way out of congestion” (at least in the long run) due to highway induced traffic and highway induced development (sprawl). Therefore, any solution to highway congestion must be multi-faceted and must, in particular, reduce the need for so much vehicular traffic. From years of other research, we know that compact development that is dense, diverse, well-designed, etc. reduces vehicle miles…
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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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