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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… Read More

The Impact of Ride Hail Services on the Accessibility of Nonprofit Services

Dyana Mason
Ride hailing services (such as Lyft and Uber) are frequently pointed to as a means of filling mobility gaps in a transportation system, especially in areas that are not well-served by transit. How might nonprofit organizations address the mobility needs of their clients through ride hailing (also known as Transportation Network Companies, or TNCs)? Many people who use nonprofit services (e.g. food assistance, social services, health care or educational support) also experience transportation… Read More

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  • Curriculum: K-12 and University

 

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