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• 1. [Article] The Effects of Roadway Capacity on Peak Narrowing - Evidence from 1995 NPTS

  Spreading of the peak is one effect of increased peak-period congestion. Due to peak spreading, the travel-time impact of congestion is mitigated for some travelers, but the inconvenience of traveling ...

  Citation × Citation Citation Abstract Copy Title: The Effects of Roadway Capacity on Peak Narrowing - Evidence from 1995 NPTS Author: Zhang, Jihong, Rufolo, Anthony M., Dueker, Kenneth, Strathman, James G. Year: 2000 Spreading of the peak is one effect of increased peak-period congestion. Due to peak spreading, the travel-time impact of congestion is mitigated for some travelers, but the inconvenience of traveling at a less-preferred time also has a cost. Alternatively, increases in capacity have their impacts on peak-period congestion mitigated by a narrowing of the peak. This reduces the travel-time savings, but it generates a benefit for those traveling closer to their preferred times. This benefit from capacity improvements has largely been ignored, and one reason is the difficulty of quantifying the effect. This paper reports on some crude attempts to quantify the peak-narrowing effect of increased capacity. Using 1995 Nationwide Personal Transportation Survey (NPTS) data, this study investigates how workers in Metropolitan Statistical Areas (MSAs) in the US respond to roadway capacity differences in terms of changing their departure time to work. It is assumed that there is some distribution of travel times given by a mean and some measure of deviation from the mean. Peak narrowing is then measured by decreases in the deviation from the mean. The peak narrowing effects are modeled for both the morning commute and all departures from home for work at any time of the day. As expected, in urban areas with higher roadway capacity per capita, workers tend to depart from home closer to the peak time. For the morning commute, the model estimates that each one-percent increase in lane-miles per capita results in workers departing from home about 5.75 percent closer to the peak time. The effects of roadway capacity are found to be statistically significant in both models. Title: The Effects of Roadway Capacity on Peak Narrowing - Evidence from 1995 NPTS Author: Zhang, Jihong, Rufolo, Anthony M., Dueker, Kenneth, Strathman, James G. Year: 2000 Spreading of the peak is one effect of increased peak-period congestion. Due to peak spreading, the travel-time impact of congestion is mitigated for some travelers, but the inconvenience of traveling at a less-preferred time also has a cost. Alternatively, increases in capacity have their impacts on peak-period congestion mitigated by a narrowing of the peak. This reduces the travel-time savings, but it generates a benefit for those traveling closer to their preferred times. This benefit from capacity improvements has largely been ignored, and one reason is the difficulty of quantifying the effect. This paper reports on some crude attempts to quantify the peak-narrowing effect of increased capacity. Using 1995 Nationwide Personal Transportation Survey (NPTS) data, this study investigates how workers in Metropolitan Statistical Areas (MSAs) in the US respond to roadway capacity differences in terms of changing their departure time to work. It is assumed that there is some distribution of travel times given by a mean and some measure of deviation from the mean. Peak narrowing is then measured by decreases in the deviation from the mean. The peak narrowing effects are modeled for both the morning commute and all departures from home for work at any time of the day. As expected, in urban areas with higher roadway capacity per capita, workers tend to depart from home closer to the peak time. For the morning commute, the model estimates that each one-percent increase in lane-miles per capita results in workers departing from home about 5.75 percent closer to the peak time. The effects of roadway capacity are found to be statistically significant in both models. Close

• 2. [Article] Self-Organizing Signals: A Better Framework for Transit Signal Priority

  Actuated traffic signal control logic has many advantages because of its responsiveness to traffic demands, short cycles, effective use of capacity leading to and recovering from oversaturation, and amenability ...

  Citation × Citation Citation Abstract Copy Title: Self-Organizing Signals: A Better Framework for Transit Signal Priority Author: Furth, Peter G. Year: 2015 Actuated traffic signal control logic has many advantages because of its responsiveness to traffic demands, short cycles, effective use of capacity leading to and recovering from oversaturation, and amenability to aggressive transit priority. Its main drawback has been its inability to provide good progression along arterials. However, the traditional way of providing progression along arterials, coordinated-actuated control with a common, fixed cycle length, has many drawbacks stemming from its long cycle lengths, inflexibility in recovering from priority interruptions, and ineffective use of capacity during periods of oversaturation. This research explores a new paradigm for traffic signal control, “self-organizing signals,” based on local actuated control but with some additional rules that create coordination mechanisms. The primary new rules proposed are for secondary extensions, in which the green may be held to serve an imminently arriving platoon, and dynamic coordination, in which small groups of closely spaced signals communicate with one another to cycle synchronously with the group’s critical intersection. Simulation tests in VISSIM performed on arterial corridors in Massachusetts and Arizona show overall delay reductions of up to 14% compared to an optimized coordinated-actuated scheme where there is no transit priority, and more than 30% in scenarios with temporary oversaturation. Tests also show that with self-organizing control, transit signal priority can be more effective than with coordinated-actuated control, reducing transit delay by about 60%, or 12 to 14 s per intersection with little impact on traffic delay. Title: Self-Organizing Signals: A Better Framework for Transit Signal Priority Author: Furth, Peter G. Year: 2015 Actuated traffic signal control logic has many advantages because of its responsiveness to traffic demands, short cycles, effective use of capacity leading to and recovering from oversaturation, and amenability to aggressive transit priority. Its main drawback has been its inability to provide good progression along arterials. However, the traditional way of providing progression along arterials, coordinated-actuated control with a common, fixed cycle length, has many drawbacks stemming from its long cycle lengths, inflexibility in recovering from priority interruptions, and ineffective use of capacity during periods of oversaturation. This research explores a new paradigm for traffic signal control, “self-organizing signals,” based on local actuated control but with some additional rules that create coordination mechanisms. The primary new rules proposed are for secondary extensions, in which the green may be held to serve an imminently arriving platoon, and dynamic coordination, in which small groups of closely spaced signals communicate with one another to cycle synchronously with the group’s critical intersection. Simulation tests in VISSIM performed on arterial corridors in Massachusetts and Arizona show overall delay reductions of up to 14% compared to an optimized coordinated-actuated scheme where there is no transit priority, and more than 30% in scenarios with temporary oversaturation. Tests also show that with self-organizing control, transit signal priority can be more effective than with coordinated-actuated control, reducing transit delay by about 60%, or 12 to 14 s per intersection with little impact on traffic delay. Close

• 3. [Article] Federal Transit Administration's Impact on Public Transportation in the United States

  The Federal Transit Administration invests in building the capacity and improving the quality of public transportation throughout the United States of America. Under FTA's leadership, public rail, bus, ...

  Citation × Citation Citation Abstract Copy Title: Federal Transit Administration's Impact on Public Transportation in the United States Author: Changchien, Amy Year: 2014 The Federal Transit Administration invests in building the capacity and improving the quality of public transportation throughout the United States of America. Under FTA's leadership, public rail, bus, trolley, ferry, and other transit services have reached greater levels of safety, reliability, availability, and accessibility. Come hear the highlights of FTA's impacts and participate in an interactive question/answer session and discussion on career options in public transportation. Title: Federal Transit Administration's Impact on Public Transportation in the United States Author: Changchien, Amy Year: 2014 The Federal Transit Administration invests in building the capacity and improving the quality of public transportation throughout the United States of America. Under FTA's leadership, public rail, bus, trolley, ferry, and other transit services have reached greater levels of safety, reliability, availability, and accessibility. Come hear the highlights of FTA's impacts and participate in an interactive question/answer session and discussion on career options in public transportation. Close

• 4. [Article] Improving the Representation of the Pedestrian Environment in Travel Demand Models, Phase I

  There is growing support for improvements to the quality of the walking environment, including more investments to promote pedestrian travel. Metropolitan planning organizations (MPOs) are improving regional ...

  Citation × Citation Citation Abstract Copy Title: Improving the Representation of the Pedestrian Environment in Travel Demand Models, Phase I Author: Clifton, Kelly J., Singleton, Patrick Allen, Muhs, Christopher Devlin, Schneider, Robert J., Lagerwey, Peter Year: 2013 There is growing support for improvements to the quality of the walking environment, including more investments to promote pedestrian travel. Metropolitan planning organizations (MPOs) are improving regional travel demand forecasting models to better represent walking and bicycling and to expand the evaluative capacity of models to address policy-relevant issues like air quality, public health, and the smart allocation of infrastructure and other resources. This report describes an innovative, spatially disaggregate method to integrate walking activity into trip-based travel models. Using data for the Portland, OR, metropolitan area, the method applies trip generation at a new micro-scale spatial unit: a 264-foot-by-264-foot (80-meters-by-80-meters) pedestrian analysis zone (PAZ). Next, a binary logit walk mode split model — using a new pedestrian environment measure — estimates the number of walk trips generated. Non-walk trips are then aggregated up to larger transportation analysis zones (TAZs) for destination choice, mode choice, and traffic assignment. Finally, there are opportunities for choosing destinations and for routing of the PAZ pedestrian trips. This method improves travel models’ sensitivity to policy-and investment-related walking influences, and it could operate as a standalone tool for rapid scenario analysis. Care must be taken when applying this method with respect to scalability, forecasting, and operational challenges. Title: Improving the Representation of the Pedestrian Environment in Travel Demand Models, Phase I Author: Clifton, Kelly J., Singleton, Patrick Allen, Muhs, Christopher Devlin, Schneider, Robert J., Lagerwey, Peter Year: 2013 There is growing support for improvements to the quality of the walking environment, including more investments to promote pedestrian travel. Metropolitan planning organizations (MPOs) are improving regional travel demand forecasting models to better represent walking and bicycling and to expand the evaluative capacity of models to address policy-relevant issues like air quality, public health, and the smart allocation of infrastructure and other resources. This report describes an innovative, spatially disaggregate method to integrate walking activity into trip-based travel models. Using data for the Portland, OR, metropolitan area, the method applies trip generation at a new micro-scale spatial unit: a 264-foot-by-264-foot (80-meters-by-80-meters) pedestrian analysis zone (PAZ). Next, a binary logit walk mode split model — using a new pedestrian environment measure — estimates the number of walk trips generated. Non-walk trips are then aggregated up to larger transportation analysis zones (TAZs) for destination choice, mode choice, and traffic assignment. Finally, there are opportunities for choosing destinations and for routing of the PAZ pedestrian trips. This method improves travel models’ sensitivity to policy-and investment-related walking influences, and it could operate as a standalone tool for rapid scenario analysis. Care must be taken when applying this method with respect to scalability, forecasting, and operational challenges. Close

• 5. [Article] Hilltop Planning Workshop Team

  "Oregon Health & Science University Night Access Plan" Oregon Health & Science University (OHSU) is a nationally renowned academic, research and health institution. At its current capacity, OHSU sees over ...

  Citation × Citation Citation Abstract Copy Title: Hilltop Planning Workshop Team Author: Anderson, Lea Year: 2016 "Oregon Health & Science University Night Access Plan" Oregon Health & Science University (OHSU) is a nationally renowned academic, research and health institution. At its current capacity, OHSU sees over 250,000 patients a year, teaches 5,000 students, employs about 16,000 people, and utilizes over 2,000 contract workers. Simply put, there are a lot of people who need to access the OHSU central campuses (Marquam Hill and South Waterfront) every day. Furthermore, because OHSU is a medical and research institution, there are large numbers of people needing to access the campuses at all hours of the day and night. Over the last five months Hilltop Planning, a group of six PSU MURP graduate students, has been working with OHSU Transportation & Parking to shed light on issues related to night transportation and access for the central campuses. One of the primary goals of the project is to "get more cars off the hill" and figure out how to make other modes both feasible and appealing for OHSU employees. Hilltop Planning has explored recommendations related to active transportation, ride-share, parking management, transit service, internal policy change and education and awareness campaigns. During the seminar Hilltop Planning will be talking about many of the issues related to night transportation more generally, as well as some of the key takeaways and findings from their work over these past few months. Final report is available online at: http://archives.pdx.edu/ds/psu/17508 Title: Hilltop Planning Workshop Team Author: Anderson, Lea Year: 2016 "Oregon Health & Science University Night Access Plan" Oregon Health & Science University (OHSU) is a nationally renowned academic, research and health institution. At its current capacity, OHSU sees over 250,000 patients a year, teaches 5,000 students, employs about 16,000 people, and utilizes over 2,000 contract workers. Simply put, there are a lot of people who need to access the OHSU central campuses (Marquam Hill and South Waterfront) every day. Furthermore, because OHSU is a medical and research institution, there are large numbers of people needing to access the campuses at all hours of the day and night. Over the last five months Hilltop Planning, a group of six PSU MURP graduate students, has been working with OHSU Transportation & Parking to shed light on issues related to night transportation and access for the central campuses. One of the primary goals of the project is to "get more cars off the hill" and figure out how to make other modes both feasible and appealing for OHSU employees. Hilltop Planning has explored recommendations related to active transportation, ride-share, parking management, transit service, internal policy change and education and awareness campaigns. During the seminar Hilltop Planning will be talking about many of the issues related to night transportation more generally, as well as some of the key takeaways and findings from their work over these past few months. Final report is available online at: http://archives.pdx.edu/ds/psu/17508 Close

• 6. [Article] Consistent Estimation of Route Choice Models for Dynamic Transit Assignment

  Dynamic transit assignment models have the potential to improve local transportation agencies’ capability to forecast the demand for public transit facilities under conditions of limited capacity or varying ...

  Citation × Citation Citation Abstract Copy Title: Consistent Estimation of Route Choice Models for Dynamic Transit Assignment Author: Hood, Jeff Year: 2016 Dynamic transit assignment models have the potential to improve local transportation agencies’ capability to forecast the demand for public transit facilities under conditions of limited capacity or varying reliability. In order to be useful in practice, the simulated route choices of passengers in these models need to reflect the behavior of actual residents observed in local travel surveys. Most analysis methods of revealed route choice preferences developed to date have either (1) not been proven to provide consistent estimates or (2) required an untenable computation time for practical applications. Furthermore, no model of transit route choice has accounted for variability in both passenger behavior and vehicle arrivals. This seminar will focus on an econometric framework that Hood Transportation Consulting designed to overcome these limitations in partnership with the second FHWA Strategic Highway Research Program, the Metropolitan Transportation Commission of the San Francisco Bay Area, the San Francisco County Transportation Authority, and the Puget Sound Regional Council. The framework is based on a recursive logit model where the traveler makes a series of dynamic choices which maximize the conditional expected utility of travel to the destination, given the sequence of vehicles which have already arrived. The model also contains new size variables to correct for the correlations caused by route overlap. Application of the new correction formulas to illustrative examples demonstrates that predictions with the model more closely match theoretically correct results than existing methods. Title: Consistent Estimation of Route Choice Models for Dynamic Transit Assignment Author: Hood, Jeff Year: 2016 Dynamic transit assignment models have the potential to improve local transportation agencies’ capability to forecast the demand for public transit facilities under conditions of limited capacity or varying reliability. In order to be useful in practice, the simulated route choices of passengers in these models need to reflect the behavior of actual residents observed in local travel surveys. Most analysis methods of revealed route choice preferences developed to date have either (1) not been proven to provide consistent estimates or (2) required an untenable computation time for practical applications. Furthermore, no model of transit route choice has accounted for variability in both passenger behavior and vehicle arrivals. This seminar will focus on an econometric framework that Hood Transportation Consulting designed to overcome these limitations in partnership with the second FHWA Strategic Highway Research Program, the Metropolitan Transportation Commission of the San Francisco Bay Area, the San Francisco County Transportation Authority, and the Puget Sound Regional Council. The framework is based on a recursive logit model where the traveler makes a series of dynamic choices which maximize the conditional expected utility of travel to the destination, given the sequence of vehicles which have already arrived. The model also contains new size variables to correct for the correlations caused by route overlap. Application of the new correction formulas to illustrative examples demonstrates that predictions with the model more closely match theoretically correct results than existing methods. Close