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
Investigating Effects of TNCs on Parking Demand and Revenues
Benjamin Clark Anne Brown
For the past century, mobility in the United States has been dictated by cars. Furthermore, cars—and even more so, the storage of cars—have dictated urban form. With cities dedicating more space to parking than even streets and roads, parking has become baked into city land use, regulations, codes, ordinances, master plans, and even finances. What happens when a car trip no longer ends in a parking space? Both transportation network companies (TNCs) and, eventually, autonomous vehicles (AVs),…
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Multimodal Trip Generation, Vehicle Ownership and Use: Characterizing The Travel Patterns of Residents of Multifamily Housing
Kelly Clifton
Many cities are reconsidering their reliance on ITE’s Trip Generation Manual, now in its 10th edition. Kelly Clifton and co-investigator Kristina Currans of the University of Arizona examine the advantages and limitations of ITE’s land use taxonomy for multifamily residences. They find that the land use categories aiming to capture intensity of development for residential land uses (high-rise apartments, for example) do not appear to capture any more variation in the vehicle or person trip…
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