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

Understanding the Accessibility, Economic and Social Equity Impacts of Urban Greenway Infrastructure

Jenny Liu
“City Greenways” is a concept proposed as a part of Portland’s 2035 Comprehensive Plan, which calls for a citywide network of park-like pedestrian and bicycle friendly streets crisscrossing the city at roughly three-mile intervals. This research establishes several approaches to measure the transportation network impact of the “City Greenways” and relate bicycle network measures to economic and social equity outcomes. Expanding upon existing literature, we derived three sets of bicycle… Read More