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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Transportation, Social Support by Family Visitation, and Depression of Older Adult Nursing Home Residents: A Mixed-Methods Study
Vivian Miller
Older adults who live in nursing homes are at an increased risk for depression and anxiety, and research has shown that social connections and family support are key factors that positively impact their mental health. However, research also suggests that one of the primary barriers to maintaining those relationships, and enabling family members to visit residents, is transportation. This NITC dissertation examined transportation barriers of family members in the community visiting their loved…
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