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• 31. [Article] Webinar: Improving Walkability at Signalized Intersections with Signal Control Strategies

  The goal of signal timing at an intersection should be to maximize efficiency for all users. In many jurisdictions, however, traffic signals are timed mostly with the goal of reducing vehicular delay. Other ...

  Citation × Citation Citation Abstract Copy Title: Webinar: Improving Walkability at Signalized Intersections with Signal Control Strategies Author: Smaglik, Edward J., Kothuri, Sirisha Murthy Year: 2017 The goal of signal timing at an intersection should be to maximize efficiency for all users. In many jurisdictions, however, traffic signals are timed mostly with the goal of reducing vehicular delay. Other road users, such as pedestrians, deserve similar focus. In legacy transportation systems, pedestrians experience delays much in excess of those that would be deemed acceptable for a motor vehicle at the same location. Excessive delay can lead to pedestrian frustration, non-compliance and ultimately decreased safety. In the North American context, implementation of strategies to address pedestrian service varies greatly across jurisdictions, and there has been limited research on incorporating alternative pedestrian treatments at signalized intersections. Recent updates to the Highway Capacity Manual (HCM 2010) have included specific multimodal delay modeling techniques offering a bit more accommodation to pedestrians, but still remain heavily vehicle-centric. While strategies such as an exclusive pedestrian phase and leading pedestrian intervals can help improve the safety of pedestrian operations, legacy service of pedestrians requires that they still must wait for their turn. This webinar will present the details of alternative pedestrian strategies, as well as the results of recent research into the impact on delay that these treatments have on all users. At the conclusion, practitioner recommendations will be presented developed from the results of a user survey, field implementations of strategies, and software-in-the-loop (SITL). Title: Webinar: Improving Walkability at Signalized Intersections with Signal Control Strategies Author: Smaglik, Edward J., Kothuri, Sirisha Murthy Year: 2017 The goal of signal timing at an intersection should be to maximize efficiency for all users. In many jurisdictions, however, traffic signals are timed mostly with the goal of reducing vehicular delay. Other road users, such as pedestrians, deserve similar focus. In legacy transportation systems, pedestrians experience delays much in excess of those that would be deemed acceptable for a motor vehicle at the same location. Excessive delay can lead to pedestrian frustration, non-compliance and ultimately decreased safety. In the North American context, implementation of strategies to address pedestrian service varies greatly across jurisdictions, and there has been limited research on incorporating alternative pedestrian treatments at signalized intersections. Recent updates to the Highway Capacity Manual (HCM 2010) have included specific multimodal delay modeling techniques offering a bit more accommodation to pedestrians, but still remain heavily vehicle-centric. While strategies such as an exclusive pedestrian phase and leading pedestrian intervals can help improve the safety of pedestrian operations, legacy service of pedestrians requires that they still must wait for their turn. This webinar will present the details of alternative pedestrian strategies, as well as the results of recent research into the impact on delay that these treatments have on all users. At the conclusion, practitioner recommendations will be presented developed from the results of a user survey, field implementations of strategies, and software-in-the-loop (SITL). Close

• 32. [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

• 33. [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

• 34. [Article] Combined Traction and Energy Recovery Motor for Electric Vehicles

  Electric vehicle manufacturers are looking for ways to optimize energy use for vehicle range extension and reduction of battery capacity. Electric motors have lower efficiencies at very low speed and high ...

  Citation × Citation Citation Abstract Copy Title: Combined Traction and Energy Recovery Motor for Electric Vehicles Author: Long, James, Wang, Xin, Kansaku, Claude, Moravec, Brian Year: 2014 Electric vehicle manufacturers are looking for ways to optimize energy use for vehicle range extension and reduction of battery capacity. Electric motors have lower efficiencies at very low speed and high torque. This is typically at vehicle launch from standstill, at very low speeds, and during energy regeneration at lower speeds and approaching standstill. The KersTech solution is a breakthrough technology allowing supplement of the electric drive with a hydraulic drive, active in lower speeds ranges, dropping out as the electric motor takes over in its higher efficiency range of operation. The report consists of four parts. Part I presents novel the hybrid vehicle simulations in MATLAB. Both the Diesel-Hydraulic Hybrid Vehicle and Electric-Hydraulic Hybrid Vehicle have been simulated and compared in this report. Part II deals with the electrical system control design. Permanent magnet synchronous motors have been widely used in hybrid electric vehicle applications. Permanent magnet synchronous motors have a small size, high efficiency and high performance. This report presents a mathematical model of permanent magnet synchronous motor. Power switching electronics are used to generate the desired voltage/current from DC source. A pulse width modulation technique controls the switching power electronic by creating a control signals which are applied to their gates. The whole circuit of the inverter based on space vector pulse width modulation is simulated in MATLAB/Simulink and its results are presented. Field-oriented control is implemented via digital signal processors to control the permanent magnet synchronous motor. Clarke and Park transformations are applied to “abc" coordinate frame of the permanent magnet synchronous motor model to get the “qd" coordinate frame used in the field oriented control technique. Hence, the developed torque and the magnetizing the flux component are controlled separately. PI controller is used to control the motor speed and torque. PI controllers are designed using frequency response method and a symmetric optimum method. The whole system is simulated based on the mathematical model of PMSM and field oriented control method with designed PI controllers. Simulation results show the PMSM to have perfect dynamic response. A digital signal processor can be used to implement the field oriented control algorithms and compute the parameters in real time. Implementation of field oriented control of a permanent magnet synchronous motor shows that the motor has satisfactory response in terms of torque ripple and speed response. Nonlinear control, including Sliding Mode Controller and State Dependent Linear Matrix Inequality Controller, are also proposed as a powerful control technique to govern the speed of the permanent magnet synchronous motor in hybrid vehicle applications. In Part III, we discuss the hydraulic system design. Finally, in Part IV, the dSPACE hardware controller is used for the overall control system design. Title: Combined Traction and Energy Recovery Motor for Electric Vehicles Author: Long, James, Wang, Xin, Kansaku, Claude, Moravec, Brian Year: 2014 Electric vehicle manufacturers are looking for ways to optimize energy use for vehicle range extension and reduction of battery capacity. Electric motors have lower efficiencies at very low speed and high torque. This is typically at vehicle launch from standstill, at very low speeds, and during energy regeneration at lower speeds and approaching standstill. The KersTech solution is a breakthrough technology allowing supplement of the electric drive with a hydraulic drive, active in lower speeds ranges, dropping out as the electric motor takes over in its higher efficiency range of operation. The report consists of four parts. Part I presents novel the hybrid vehicle simulations in MATLAB. Both the Diesel-Hydraulic Hybrid Vehicle and Electric-Hydraulic Hybrid Vehicle have been simulated and compared in this report. Part II deals with the electrical system control design. Permanent magnet synchronous motors have been widely used in hybrid electric vehicle applications. Permanent magnet synchronous motors have a small size, high efficiency and high performance. This report presents a mathematical model of permanent magnet synchronous motor. Power switching electronics are used to generate the desired voltage/current from DC source. A pulse width modulation technique controls the switching power electronic by creating a control signals which are applied to their gates. The whole circuit of the inverter based on space vector pulse width modulation is simulated in MATLAB/Simulink and its results are presented. Field-oriented control is implemented via digital signal processors to control the permanent magnet synchronous motor. Clarke and Park transformations are applied to “abc" coordinate frame of the permanent magnet synchronous motor model to get the “qd" coordinate frame used in the field oriented control technique. Hence, the developed torque and the magnetizing the flux component are controlled separately. PI controller is used to control the motor speed and torque. PI controllers are designed using frequency response method and a symmetric optimum method. The whole system is simulated based on the mathematical model of PMSM and field oriented control method with designed PI controllers. Simulation results show the PMSM to have perfect dynamic response. A digital signal processor can be used to implement the field oriented control algorithms and compute the parameters in real time. Implementation of field oriented control of a permanent magnet synchronous motor shows that the motor has satisfactory response in terms of torque ripple and speed response. Nonlinear control, including Sliding Mode Controller and State Dependent Linear Matrix Inequality Controller, are also proposed as a powerful control technique to govern the speed of the permanent magnet synchronous motor in hybrid vehicle applications. In Part III, we discuss the hydraulic system design. Finally, in Part IV, the dSPACE hardware controller is used for the overall control system design. Close

• 35. [Article] Contextual Influences on Trip Generation

  There is national interest in building data that expands upon the existing Institute of Transportation Engineers (ITE) trip generation rates to include sites located in a multi-modal context. Current ITE ...

  Citation × Citation Citation Abstract Copy Title: Contextual Influences on Trip Generation Author: Clifton, Kelly J., Currans, Kristina Marie, Muhs, Christopher D. Year: 2012 There is national interest in building data that expands upon the existing Institute of Transportation Engineers (ITE) trip generation rates to include sites located in a multi-modal context. Current ITE rates represent travel behavior for development in single lots and uses, primarily measured in low-density suburban areas. Despite evidence that a more compact urban form, access to transit and a greater mix of uses generates fewer and shorter vehicle trips, local governments are often compelled to use current ITE trip generation rates to evaluate transportation impacts and calculate transportation system development charges (TSDCs). This is due to: a) the expense of collecting local data, b) lack of alternative sources of information, c) the strong industry bias toward using ITE published rates and d) the absence of a empirically tested methodology for adjusting those rates for development occurring in different land use and transportation contexts. Compounding these challenges, cities in Oregon are required to demonstrate that planning and zoning changes will not degrade the performance of state-owned transportation facilities compared to the levels of service documented in the Regional Transportation Plan under the Oregon Transportation Planning Rule, section -0060, and Oregon Highway Plan, Policy 1.F.6. These requirements can conflict with regional policies in Metro's 2040 Growth Concept that call for development of mixed-use centers and corridors to support jobs and freight reliability, a compact urban form and leverage transportation investments such as high capacity transit. Thus, there are gaps in the understanding about how best to evaluate, mitigate and plan for growth under these conditions. This research proposes to develop multi-modal trip generation rates that better reflect the relationship between land use, transportation and travel demand for specific land use types located in various urban settings. The project aims to collect local data (using multi-modal counts and establishment surveys) on a few specific land uses (deemed most problematic to estimate demand and occurring across the spectrum of urban conditions) to develop trip generation rates that are sensitive to demographic, land use and transportation contexts. These new trip rates will be compared to the ITE rates for the same land use category and a methodology for adjusting the ITE rates will be developed. This adjustment methodology will be validated, using additional data collected in this research. The research will be documented and made available to local partners and disseminated widely to reach out to other communities across the country. The research conducted for this project would account for how the built environment (e.g., both land use and transportation) influences travel behavior (number of trips, trip length, mode choice), and determine trip rates that reflect the entire activity spectrum of different development/place typologies. This is extremely important in determining the impact of different development types on the transportation system to: 1) avoid over-planning the system for the surrounding land uses; (2) suggest strategies and investment priorities to encourage more compact, mixed-use areas with more transportation choices and 3) avoid creating regulatory and/or financial barriers to compact form envisioned by local, regional and statewide plans (i.e. uniform TSDCs can result in lower impact development paying the same rates, and thus subsidizing development with higher impact costs to the transportation system). The documentation of the findings and methodology will be applicable to current and future growth and be transferable to other communities, locally and nationally, beyond the Portland region. Title: Contextual Influences on Trip Generation Author: Clifton, Kelly J., Currans, Kristina Marie, Muhs, Christopher D. Year: 2012 There is national interest in building data that expands upon the existing Institute of Transportation Engineers (ITE) trip generation rates to include sites located in a multi-modal context. Current ITE rates represent travel behavior for development in single lots and uses, primarily measured in low-density suburban areas. Despite evidence that a more compact urban form, access to transit and a greater mix of uses generates fewer and shorter vehicle trips, local governments are often compelled to use current ITE trip generation rates to evaluate transportation impacts and calculate transportation system development charges (TSDCs). This is due to: a) the expense of collecting local data, b) lack of alternative sources of information, c) the strong industry bias toward using ITE published rates and d) the absence of a empirically tested methodology for adjusting those rates for development occurring in different land use and transportation contexts. Compounding these challenges, cities in Oregon are required to demonstrate that planning and zoning changes will not degrade the performance of state-owned transportation facilities compared to the levels of service documented in the Regional Transportation Plan under the Oregon Transportation Planning Rule, section -0060, and Oregon Highway Plan, Policy 1.F.6. These requirements can conflict with regional policies in Metro's 2040 Growth Concept that call for development of mixed-use centers and corridors to support jobs and freight reliability, a compact urban form and leverage transportation investments such as high capacity transit. Thus, there are gaps in the understanding about how best to evaluate, mitigate and plan for growth under these conditions. This research proposes to develop multi-modal trip generation rates that better reflect the relationship between land use, transportation and travel demand for specific land use types located in various urban settings. The project aims to collect local data (using multi-modal counts and establishment surveys) on a few specific land uses (deemed most problematic to estimate demand and occurring across the spectrum of urban conditions) to develop trip generation rates that are sensitive to demographic, land use and transportation contexts. These new trip rates will be compared to the ITE rates for the same land use category and a methodology for adjusting the ITE rates will be developed. This adjustment methodology will be validated, using additional data collected in this research. The research will be documented and made available to local partners and disseminated widely to reach out to other communities across the country. The research conducted for this project would account for how the built environment (e.g., both land use and transportation) influences travel behavior (number of trips, trip length, mode choice), and determine trip rates that reflect the entire activity spectrum of different development/place typologies. This is extremely important in determining the impact of different development types on the transportation system to: 1) avoid over-planning the system for the surrounding land uses; (2) suggest strategies and investment priorities to encourage more compact, mixed-use areas with more transportation choices and 3) avoid creating regulatory and/or financial barriers to compact form envisioned by local, regional and statewide plans (i.e. uniform TSDCs can result in lower impact development paying the same rates, and thus subsidizing development with higher impact costs to the transportation system). The documentation of the findings and methodology will be applicable to current and future growth and be transferable to other communities, locally and nationally, beyond the Portland region. Close