Mar 16, 2011

It’s a common occurrence: a digital signboard over the freeway tells you to expect a 15-minute trip, but traffic clears and you arrive in 10 minutes. Or, worse, you hit a clog and arrive in 30 minutes.

Sometimes those signboards, called dynamic message signs, are way off, Portland State University researcher Kristin Tufte found. But sometimes that doesn’t matter.

Tufte examined the signboards, called dynamic message signs, along Portland-area freeways in an OTREC project. Drivers typically reach their destinations earlier or later than the signs told them to expect when a so-called “shock wave” forms or dissipates; that is, when traffic suddenly bunches or clears up.

Currently, only three of the 30 or so message signs in the Portland metro area display travel times. Detectors at freeway onramps feed those signs. As a result, large swaths of freeway without onramps also have no data. To be most useful, new message signs would require more detectors in certain areas.

Take the busy Marquam Bridge in Portland, where busy freeways merge and there is no signboard. “There’s no detection for the whole length of the bridge,” Tufte said. “If you really want to have accurate travel times, you have to have detection there.”

As expected, Tufte found that traffic bunching or clearing in blind zones can throw off the accuracy of travel times displayed. Surprisingly, that inaccurate information is often good enough....

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Mar 17, 2009

OTREC helped sponsor the 50th Annual Forum of the Transportation Research Forum, held in Portland, Oregon March 16-18, 2009. OTREC faculty partner B. Starr McMullen of Oregon State University served as conference chair and OTREC sponsored the Keynote Speaker Daniel McFadden, 2000 Nobel Prize recipient in Economics, who presented “Sociality, Rationality and the Ecology of Choice.” OTREC faculty member Miguel Figliozzi presented “A Study of Transportation Disruption Causes and Costs in Containerized Maritime Transportation,” director Robert Bertini presented “Can Sensors Be Used to Provide Accurate Travel Time Information?,” and chaired a session on “Transportation Measures: Which Ones and How Do We Measure Them?,” PSU student Meead Saberi presented “Evaluating the Factors Affecting Student Travel Mode Choice,” PSU student Alex Bigazzi presented a poster “Adding Sustainability Performance Measures to a Transportation Data Archive,” PSU Student Meead Saberi presented a poster “Does Weather Affect Traffic Flow on Freeways?,” Miguel Figliozzi presented a poster with Kristin Tufte, “Integration and Visualization Challenges and Opportunities for Online Freight Data Mapping,” and PSU student Wei Feng presented a poster “Characteristics of Transitions in Freeway Traffic.” Congratulations to Prof. McMullent, TRF and all participants for a successful conference!

Feb 04, 2008

Faculty from all four OTREC partner campuses participated in the 2008 Northwest Transportation Conference at Oregon State University February 5-7. Under the theme of "Making the Most of What We Have: Innovations for the 21st Century," faculty served as session moderators and as roundtable members for a variety of topics. Portland State University attendees included Jennifer Dill, Peter Dusicka, Miguel Figliozzi, Hau Hagedorn, Chris Monsere, Tony Rufolo, Kristin Tufte and Brent Zenobia. University of Oregon faculty attending were Nico Larco, Marc Schlossberg and Yizhao Yang. Faculty from Oregon State University included Karen Dixon, Chris Higgins, Starr McMullen, Todd Scholz, Michael Scott and Lei Zhang. OTREC Associate Director Roger Lindgren from the Oregon Institute of Technology also attended. More information about the conference and program sessions: NWTC.

Aug 13, 2007

Allison Dane, staff member from Congressman Peter DeFazio’s office, who specializes in work with the House Transportation and Infrastructure Committee, visited Portland State University in August for an update on transportation research conducted in the ITS Lab, at PSU and within the Oregon Transportation Research and Education Consortium (OTREC). PSU faculty, including Professors Bertini, Dusicka, Smith, Tufte and Maier discussed their ongoing research efforts. Prof. Higgins from OSU, and Betsy Boyd from UO, plus OTREC staff (Hau Hagedorn, Jenny Kincaid and Rie Anderson) also participated in the meeting.