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• 131. [Article] Evaluating the Level-of-Service of Protected Bike Lanes

  Summary: The most recent edition of the Highway Capacity Manual (HCM) contains analysis procedures for measuring the level-of-service (LOS), also referred to as quality of service, provided by an urban ...

  Citation × Citation Citation Abstract Copy Title: Evaluating the Level-of-Service of Protected Bike Lanes Author: Foster, Nick Year: 2014 Summary: The most recent edition of the Highway Capacity Manual (HCM) contains analysis procedures for measuring the level-of-service (LOS), also referred to as quality of service, provided by an urban roadway to bicyclists. The method uses different design and operating features of the roadway segment (e.g. width, motor vehicle volumes and speeds) to assess an LOS grade of A (best) to F (worst). These procedures are used by planners and engineers to recommend how existing streets could be retrofitted or new streets designed to better serve people on bicycles (and other modes). However, the current HCM does not include methods that address protected bike lanes (aka “cycle tracks” or “separated bike lanes”), only conventional striped bike lanes, shoulders, and shared streets. There are other methods for predicting comfort from a bicyclist’s perspective that do consider protected bike lanes, but they are either based only on expert opinion or on surveys in Denmark. This presentation will describe how to evaluate the level-of-service of a protected bike lane using results from surveys conducted in the United States. The model developed by this project could be used to supplement the current HCM to objectively consider a wider range of options for improving the environment for bicycling. This is increasingly important as the implementation of, and demand for, protected bike lanes surges around the US. Title: Evaluating the Level-of-Service of Protected Bike Lanes Author: Foster, Nick Year: 2014 Summary: The most recent edition of the Highway Capacity Manual (HCM) contains analysis procedures for measuring the level-of-service (LOS), also referred to as quality of service, provided by an urban roadway to bicyclists. The method uses different design and operating features of the roadway segment (e.g. width, motor vehicle volumes and speeds) to assess an LOS grade of A (best) to F (worst). These procedures are used by planners and engineers to recommend how existing streets could be retrofitted or new streets designed to better serve people on bicycles (and other modes). However, the current HCM does not include methods that address protected bike lanes (aka “cycle tracks” or “separated bike lanes”), only conventional striped bike lanes, shoulders, and shared streets. There are other methods for predicting comfort from a bicyclist’s perspective that do consider protected bike lanes, but they are either based only on expert opinion or on surveys in Denmark. This presentation will describe how to evaluate the level-of-service of a protected bike lane using results from surveys conducted in the United States. The model developed by this project could be used to supplement the current HCM to objectively consider a wider range of options for improving the environment for bicycling. This is increasingly important as the implementation of, and demand for, protected bike lanes surges around the US. Close

• 132. [Article] Towards Effective Design Treatment for Right Turns at Intersections with Bicycle Traffic

  The overall goal of this research was to quantify the safety performance of alternative traffic control strategies to mitigate right-turning-vehicle/bicycle collisions, often called "right-hook" crashes, ...

  Citation × Citation Citation Abstract Copy Title: Towards Effective Design Treatment for Right Turns at Intersections with Bicycle Traffic Author: Hurwitz, David, Monsere, Christopher Year: 2016 The overall goal of this research was to quantify the safety performance of alternative traffic control strategies to mitigate right-turning-vehicle/bicycle collisions, often called "right-hook" crashes, at signalized intersections in Oregon. A two stage experiment was developed in the OSU high-fidelity driving simulator to investigate the causal factors of right-hook crashes at signalized intersections with a striped bike lane and no right-turn lane, and to then identify and evaluate alternative design treatments that could mitigate the occurrence of right-hook crashes. Experiment 1 investigated motorist and environmental related causal factors of right-hook crashes, using three different motorist performance measures: (1) visual attention, (2) situational awareness (SA) and (3) crash avoidance behavior. Data was collected from 51 participants (30 male and 21 female) turning right 820 times in 21 different experimental scenarios. It was determined that the worst case right-hook scenario occurred when a bicycle was approaching the intersection at a higher speed (16 mph) and positioned in the blind zone of the motorist. In crash and near crash situations (measured by time-to-collision) the most common cause was a failure of the driver to actively search for the adjacent bicyclist (situational awareness level 1), although failures were also determined to occur due to failures of projection (i.e. incorrectly assuming that the bicycle would yield or that there was enough time to turn in front of the bicycle). Elements of driver performance and gap acceptance collected in the first stage simulator experiment were field validated based on 144 hrs of video to provide additional confidence in the findings. Title: Towards Effective Design Treatment for Right Turns at Intersections with Bicycle Traffic Author: Hurwitz, David, Monsere, Christopher Year: 2016 The overall goal of this research was to quantify the safety performance of alternative traffic control strategies to mitigate right-turning-vehicle/bicycle collisions, often called "right-hook" crashes, at signalized intersections in Oregon. A two stage experiment was developed in the OSU high-fidelity driving simulator to investigate the causal factors of right-hook crashes at signalized intersections with a striped bike lane and no right-turn lane, and to then identify and evaluate alternative design treatments that could mitigate the occurrence of right-hook crashes. Experiment 1 investigated motorist and environmental related causal factors of right-hook crashes, using three different motorist performance measures: (1) visual attention, (2) situational awareness (SA) and (3) crash avoidance behavior. Data was collected from 51 participants (30 male and 21 female) turning right 820 times in 21 different experimental scenarios. It was determined that the worst case right-hook scenario occurred when a bicycle was approaching the intersection at a higher speed (16 mph) and positioned in the blind zone of the motorist. In crash and near crash situations (measured by time-to-collision) the most common cause was a failure of the driver to actively search for the adjacent bicyclist (situational awareness level 1), although failures were also determined to occur due to failures of projection (i.e. incorrectly assuming that the bicycle would yield or that there was enough time to turn in front of the bicycle). Elements of driver performance and gap acceptance collected in the first stage simulator experiment were field validated based on 144 hrs of video to provide additional confidence in the findings. Close

• 133. [Article] The Trade-offs between Population Density and Households' Transportation-housing Costs

  As metropolitan area governments and others promote density-promoting “smart growth” policies, finer analysis is needed to quantify the impact of such policies on households' transportation and housing ...

  Citation × Citation Citation Abstract Copy Title: The Trade-offs between Population Density and Households' Transportation-housing Costs Author: Wang, Haizhong Year: 2015 As metropolitan area governments and others promote density-promoting “smart growth” policies, finer analysis is needed to quantify the impact of such policies on households' transportation and housing costs. Existing research suggests that households in urban areas trade-off between housing costs and transportation costs, but does not explore how policies to increase urban densities might explicitly impact this balance. Furthermore, the research does not adequately distinguish between the effect of urban area density and the effects of other factors associated with urban area density (e.g metropolitan area size and household incomes) on housing costs. This research uses the 2000 Census Public Use Micro Sample (PUMS) person and household data from 23 of the nation's most densely populated states to identify the impact of increased population density on three housing cost measures: household rents, housing unit values, and monthly mortgage payments. Log linear models were estimated for each housing cost measure using least-squares regression. Dependent variables included household, housing unit, and geographic area characteristics, including population density. The models were found to be very similar to one another in terms of the statistical significance and values of estimated model parameters. Population density (measured at the PUMS area level) was found to be statistically significant at the 0.01 level for all housing cost measures. Although significant, the parameter estimates show that the elasticity of housing cost with respect to population density is low, ranging from 0.041 to 0.05. This research also explores the relationship between housing costs and accessibility. Results show that households living in areas closer to jobs (as indicated by shorter average commute times) and households utilizing fixed route transit systems have marginally higher housing costs. Title: The Trade-offs between Population Density and Households' Transportation-housing Costs Author: Wang, Haizhong Year: 2015 As metropolitan area governments and others promote density-promoting “smart growth” policies, finer analysis is needed to quantify the impact of such policies on households' transportation and housing costs. Existing research suggests that households in urban areas trade-off between housing costs and transportation costs, but does not explore how policies to increase urban densities might explicitly impact this balance. Furthermore, the research does not adequately distinguish between the effect of urban area density and the effects of other factors associated with urban area density (e.g metropolitan area size and household incomes) on housing costs. This research uses the 2000 Census Public Use Micro Sample (PUMS) person and household data from 23 of the nation's most densely populated states to identify the impact of increased population density on three housing cost measures: household rents, housing unit values, and monthly mortgage payments. Log linear models were estimated for each housing cost measure using least-squares regression. Dependent variables included household, housing unit, and geographic area characteristics, including population density. The models were found to be very similar to one another in terms of the statistical significance and values of estimated model parameters. Population density (measured at the PUMS area level) was found to be statistically significant at the 0.01 level for all housing cost measures. Although significant, the parameter estimates show that the elasticity of housing cost with respect to population density is low, ranging from 0.041 to 0.05. This research also explores the relationship between housing costs and accessibility. Results show that households living in areas closer to jobs (as indicated by shorter average commute times) and households utilizing fixed route transit systems have marginally higher housing costs. Close

• 134. [Article] The Bridge and the City

  Daniel Biau, international consultant, civil engineer and author of The Bridge and the City: A Universal Love Story, will share insights on urbanization and bridges. Across countries and centuries, the ...

  Citation × Citation Citation Abstract Copy Title: The Bridge and the City Author: Biau, Daniel Year: 2016 Daniel Biau, international consultant, civil engineer and author of The Bridge and the City: A Universal Love Story, will share insights on urbanization and bridges. Across countries and centuries, the session will explore a fundamental social and demographic change: the emergence of a planet of towns and cities. But it will look at this densification of human and economic relations through a specific lens, the increased connectivity triggered by strategic urban bridges. As places of encounters and exchanges, bridges have played a major role in the urbanization of our planet. With reference to twenty-four world cities, the presentation will explain how these monuments have influenced urban development over all continents. The most fascinating cities in Europe (Paris, Rome, Istanbul, Saint-Petersburg, London) all possess fantastic bridges. The same could be said about North American cities (New York, San Francisco, Portland, Chicago) and cities in other regions of the world. Besides, the most famous bridges have almost always been erected at a critical juncture in the history of their host cities. It could be argued that “the bridge makes the city” because, in history, the city reaches a new dimension when its “grand” bridge is inaugurated. Bridges can be seen as founding milestones, buttonholes and laces of the urban fabric, as well as signatures of the built environment. As architectural objects and engineering feats, they directly reflect the technical achievements and aesthetical values of their time, as well as the socio-cultural and economic context of their construction. The lecture will illustrate a universal relationship, over space and time, from Rome and its Ponte Sant’Angelo (134) and Paris and its Pont-Neuf (1607) to New York and its Brooklyn Bridge (1883) and Shanghai and its Nanpu Da Qiao (1991). It will also draw lessons from that history for contemporary urban planning. Title: The Bridge and the City Author: Biau, Daniel Year: 2016 Daniel Biau, international consultant, civil engineer and author of The Bridge and the City: A Universal Love Story, will share insights on urbanization and bridges. Across countries and centuries, the session will explore a fundamental social and demographic change: the emergence of a planet of towns and cities. But it will look at this densification of human and economic relations through a specific lens, the increased connectivity triggered by strategic urban bridges. As places of encounters and exchanges, bridges have played a major role in the urbanization of our planet. With reference to twenty-four world cities, the presentation will explain how these monuments have influenced urban development over all continents. The most fascinating cities in Europe (Paris, Rome, Istanbul, Saint-Petersburg, London) all possess fantastic bridges. The same could be said about North American cities (New York, San Francisco, Portland, Chicago) and cities in other regions of the world. Besides, the most famous bridges have almost always been erected at a critical juncture in the history of their host cities. It could be argued that “the bridge makes the city” because, in history, the city reaches a new dimension when its “grand” bridge is inaugurated. Bridges can be seen as founding milestones, buttonholes and laces of the urban fabric, as well as signatures of the built environment. As architectural objects and engineering feats, they directly reflect the technical achievements and aesthetical values of their time, as well as the socio-cultural and economic context of their construction. The lecture will illustrate a universal relationship, over space and time, from Rome and its Ponte Sant’Angelo (134) and Paris and its Pont-Neuf (1607) to New York and its Brooklyn Bridge (1883) and Shanghai and its Nanpu Da Qiao (1991). It will also draw lessons from that history for contemporary urban planning. Close

• 135. [Article] Webinar: Transport Cost Index: A New Comprehensive Performance Measure for Transportation and Land Use

  Recent federal and state policies are placing increasing emphasis on using comprehensive transportation performance measures to guide transportation decision making processes covering policy areas ranging ...

  Citation × Citation Citation Abstract Copy Title: Webinar: Transport Cost Index: A New Comprehensive Performance Measure for Transportation and Land Use Author: Wang, Liming Year: 2015 Recent federal and state policies are placing increasing emphasis on using comprehensive transportation performance measures to guide transportation decision making processes covering policy areas ranging from mobility, safety, economy and livability, to issues of equity and environment. While it is relatively easy to build consensus on mobility measures that center on the transportation system alone, it is much harder for performance measures to incorporate both transportation and land use, loosely defined as accessibility measures, even with continuous efforts to catalog and design such measures. Two projects at PSU sponsored by Oregon DOT and National Institute of Transportation Communities (NITC) aim to to develop and evaluate Transport Cost Index (TCI), a comprehensive performance measure for transportation and land use, in order to fill important gaps in popular accessibility measures: TCI is a composite indicator that is able to present an overall picture of a community’s accessibility, while at the same time is relatively easy to interpret for policy makers and the public; It fills gaps in policy areas represented by popular performance measures of land use and transportation systems, in particular the equity and balance aspects; It is applicable for monitoring historical and projected trends (benchmarking), evaluating and comparing outcomes from what-if scenarios (scenario evaluation), as well as to report the current status. The webinar reviews similar measures, describes the rationale, design and implementation of TCI, and presents results of its applications in Portland and Corvallis, Oregon, as well as preliminary testing results from Salt Lake City, Utah and Tampa Bay, Florida. Title: Webinar: Transport Cost Index: A New Comprehensive Performance Measure for Transportation and Land Use Author: Wang, Liming Year: 2015 Recent federal and state policies are placing increasing emphasis on using comprehensive transportation performance measures to guide transportation decision making processes covering policy areas ranging from mobility, safety, economy and livability, to issues of equity and environment. While it is relatively easy to build consensus on mobility measures that center on the transportation system alone, it is much harder for performance measures to incorporate both transportation and land use, loosely defined as accessibility measures, even with continuous efforts to catalog and design such measures. Two projects at PSU sponsored by Oregon DOT and National Institute of Transportation Communities (NITC) aim to to develop and evaluate Transport Cost Index (TCI), a comprehensive performance measure for transportation and land use, in order to fill important gaps in popular accessibility measures: TCI is a composite indicator that is able to present an overall picture of a community’s accessibility, while at the same time is relatively easy to interpret for policy makers and the public; It fills gaps in policy areas represented by popular performance measures of land use and transportation systems, in particular the equity and balance aspects; It is applicable for monitoring historical and projected trends (benchmarking), evaluating and comparing outcomes from what-if scenarios (scenario evaluation), as well as to report the current status. The webinar reviews similar measures, describes the rationale, design and implementation of TCI, and presents results of its applications in Portland and Corvallis, Oregon, as well as preliminary testing results from Salt Lake City, Utah and Tampa Bay, Florida. Close

• 136. [Article] Webinar: Impacts of Roadway and Traffic Characteristics on Air Pollution Risks for Bicyclists

  Active travel such as walking and bicycling can lead to health benefits through an increase in physical activity. At the same time, more active travelers breath more and so can experience high pollution ...

  Citation × Citation Citation Abstract Copy Title: Webinar: Impacts of Roadway and Traffic Characteristics on Air Pollution Risks for Bicyclists Author: Bigazzi, Alexander Y. Year: 2015 Active travel such as walking and bicycling can lead to health benefits through an increase in physical activity. At the same time, more active travelers breath more and so can experience high pollution inhalation rates during travel. This webinar will review the state of knowledge about how roadway and traffic characteristics impact air pollution risks for bicyclists, including the latest PSU research quantifying bicyclists' uptake of traffic-related air pollution using on-road measurements in Portland. The PSU research team including Alex Bigazzi, Jim Pankow, and Miguel Figliozzi quantified bicyclist exposure concentrations on different types of roadways, respiration responses to exertion level, and changes in blood concentrations of pollutants. Implications for planners, engineers, and policy-makers will be discussed, including guidance for more pollution-conscious bicycle network planning and design. Additionally, ways for individual travelers to reduce their air pollution risks will be discussed. This 60-minute webinar is eligible for one hour of training which equals 1 CM or 1 PDH. NITC applies to the AICP for Certification Maintenance credit for each webinar. We will provide an attendance certificate to those who document their professional development hours. Title: Webinar: Impacts of Roadway and Traffic Characteristics on Air Pollution Risks for Bicyclists Author: Bigazzi, Alexander Y. Year: 2015 Active travel such as walking and bicycling can lead to health benefits through an increase in physical activity. At the same time, more active travelers breath more and so can experience high pollution inhalation rates during travel. This webinar will review the state of knowledge about how roadway and traffic characteristics impact air pollution risks for bicyclists, including the latest PSU research quantifying bicyclists' uptake of traffic-related air pollution using on-road measurements in Portland. The PSU research team including Alex Bigazzi, Jim Pankow, and Miguel Figliozzi quantified bicyclist exposure concentrations on different types of roadways, respiration responses to exertion level, and changes in blood concentrations of pollutants. Implications for planners, engineers, and policy-makers will be discussed, including guidance for more pollution-conscious bicycle network planning and design. Additionally, ways for individual travelers to reduce their air pollution risks will be discussed. This 60-minute webinar is eligible for one hour of training which equals 1 CM or 1 PDH. NITC applies to the AICP for Certification Maintenance credit for each webinar. We will provide an attendance certificate to those who document their professional development hours. Close

• 137. [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

• 138. [Article] Understanding Transportation in Urban China - Local Residents vs Migrant Workers

  With rapid urbanization in China and other developing economies around the world, it has become imperative to understand household transportation behavior and expenditures in these urban areas. The objective ...

  Citation × Citation Citation Abstract Copy Title: Understanding Transportation in Urban China - Local Residents vs Migrant Workers Author: Liu, Jenny H. Year: 2016 With rapid urbanization in China and other developing economies around the world, it has become imperative to understand household transportation behavior and expenditures in these urban areas. The objective of this study is to examine the differences in the determinants of household transportation expenditures within two very distinct populations in Chinese cities: local residents and migrant workers. In order to craft policies or strategies promoting sustainable transportation or livability, it is essential to understand whether the drivers that push the migrant population towards spending more on transportation or owning bikes or motorbikes are similar to drivers for the rest of the population. This is further complicated by the differential treatment of households within China’s hukou (household registration) system which determines eligibility to receive public benefits in housing or education. Because nearly 40% of the population in urban areas are migrants, it is particularly important to examine how the transportation choices and behavior of migrant households may diverge (or not) from the rest of the urban dwellers. Utilizing a unique dataset that surveys both types of households, we utilize descriptive statistics and regression models to analyze their transportation expenditures. We find that household income level and automobile ownership are the strongest predictors of household transportation expenditures. In addition, larger local resident households who are younger tend to spend more on transportation while migrant households generally spend less on transportation, particularly those with stronger social networks and those who do not hold urban hukou status. We conclude that significant differences do exist and may be exacerbated by inequitable access to public services, housing opportunities and other urban amenities in addition to major differences in household composition, preferences and levels of participation in the urban economic and social systems. Title: Understanding Transportation in Urban China - Local Residents vs Migrant Workers Author: Liu, Jenny H. Year: 2016 With rapid urbanization in China and other developing economies around the world, it has become imperative to understand household transportation behavior and expenditures in these urban areas. The objective of this study is to examine the differences in the determinants of household transportation expenditures within two very distinct populations in Chinese cities: local residents and migrant workers. In order to craft policies or strategies promoting sustainable transportation or livability, it is essential to understand whether the drivers that push the migrant population towards spending more on transportation or owning bikes or motorbikes are similar to drivers for the rest of the population. This is further complicated by the differential treatment of households within China’s hukou (household registration) system which determines eligibility to receive public benefits in housing or education. Because nearly 40% of the population in urban areas are migrants, it is particularly important to examine how the transportation choices and behavior of migrant households may diverge (or not) from the rest of the urban dwellers. Utilizing a unique dataset that surveys both types of households, we utilize descriptive statistics and regression models to analyze their transportation expenditures. We find that household income level and automobile ownership are the strongest predictors of household transportation expenditures. In addition, larger local resident households who are younger tend to spend more on transportation while migrant households generally spend less on transportation, particularly those with stronger social networks and those who do not hold urban hukou status. We conclude that significant differences do exist and may be exacerbated by inequitable access to public services, housing opportunities and other urban amenities in addition to major differences in household composition, preferences and levels of participation in the urban economic and social systems. Close

• 139. [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

• 140. [Article] Evaluation of Transportation Microenvironments Through Assessment of Cyclysts' Exposure to Traffic-Related Particulate Matter

  It is well established that vehicles powered by carbon-based fuels (e.g. gasoline, diesel) have a negative impact on air quality, especially in urban centers. Traditionally, air quality conformity studies ...

  Citation × Citation Citation Abstract Copy Title: Evaluation of Transportation Microenvironments Through Assessment of Cyclysts' Exposure to Traffic-Related Particulate Matter Author: George, Linda A., Figliozzi, Miguel A., Monsere, Christopher M., Kendrick, Christine M., Bigazzi, Alexander Y, Moore, Adam Year: 2011 It is well established that vehicles powered by carbon-based fuels (e.g. gasoline, diesel) have a negative impact on air quality, especially in urban centers. Traditionally, air quality conformity studies analyze the macroenvironmental impact of transportation corridors, as they relate to regional air quality management concerns. Urban residents spend a considerable amount of outdoor time in transportation microenvironments as pedestrians, bicycle commuters, people waiting to use public transport, residents and workers situated along roadways, and commuters within vehicles. An emerging area of research has shown that human health impacts within transport microenvironments can be considerable, but have not been well-characterized. As urban public policies increasingly encourage the use of multi-mode commuting in dense urban centers, decisionmakers need reliable modeling tools to predict and mitigate the health consequences of vehicle-related emissions in transportation microenvironments. This project proposes unique integration of real-time multi-modal personal exposure monitoring with real-time detailed traffic monitoring in order to develop a computer model that links traffic characteristics, emissions, built environment configuration, mode of travel and health impacts. Existing emission and dispersion models do not take direct account of the dynamic nature of traffic and how emissions impact the health of the diversity of urban dwellers, bus commuters, pedestrians, and bicycle riders. Typical approaches use highly aggregated vehicle data and computed link speeds to assign an emission factor to the traffic, an assumed proportion of which is trucks. In addition, existing methods to assess environmental impacts tend to focus on the production source of the pollutant not the impacts, which require information on population activities and its proximity to vehicle flows. Personal exposure studies document significant air quality impacts within the transportation microenvironment but do not integrate dynamic traffic and emission analysis. Previous research argues for a comprehensive approach. From the perspective of mitigating transportation impacts, it is significant to understand: a) exposure to the pollution, which in turn requires assessment of where people are in relation to the source of the pollutant, and b) the relation between pollution and vehicle flows. This research will target highly polluted high exposure hotspots in Portland, e.g. high traffic flows running through a major trip destination area for shopping, entertainment, education, or health care highly dependent on mode of travel, traffic levels and type, and built environment characteristics. Our approach is to conduct field studies to measure personal exposure to particulate matter as a function of transportation mode through pre-determined routes in the city. Exposure levels, position, time and rate of travel will be recorded. Simultaneously we will collect detailed traffic data that will provide type/number of vehicle, speed of travel and start/stop behavior. GIS analysis of the urban form and land use characteristics will establish built environment parameters. These data will be integrated into a built environment-travel mode-exposure model. The major scientific innovations offered by this project are: 1) integration of detailed and real-time exposure/emissions with a real-time traffic measurement approach, and 2) development of an integrated emissions and transportation model that combines traffic characteristics, emissions, built environment configuration, mode of travel and predicted health impacts. The outcomes of the research will be of importance to the general public, urban communities, departments of transportation charged with managing urban traffic, and public health authorities. Title: Evaluation of Transportation Microenvironments Through Assessment of Cyclysts' Exposure to Traffic-Related Particulate Matter Author: George, Linda A., Figliozzi, Miguel A., Monsere, Christopher M., Kendrick, Christine M., Bigazzi, Alexander Y, Moore, Adam Year: 2011 It is well established that vehicles powered by carbon-based fuels (e.g. gasoline, diesel) have a negative impact on air quality, especially in urban centers. Traditionally, air quality conformity studies analyze the macroenvironmental impact of transportation corridors, as they relate to regional air quality management concerns. Urban residents spend a considerable amount of outdoor time in transportation microenvironments as pedestrians, bicycle commuters, people waiting to use public transport, residents and workers situated along roadways, and commuters within vehicles. An emerging area of research has shown that human health impacts within transport microenvironments can be considerable, but have not been well-characterized. As urban public policies increasingly encourage the use of multi-mode commuting in dense urban centers, decisionmakers need reliable modeling tools to predict and mitigate the health consequences of vehicle-related emissions in transportation microenvironments. This project proposes unique integration of real-time multi-modal personal exposure monitoring with real-time detailed traffic monitoring in order to develop a computer model that links traffic characteristics, emissions, built environment configuration, mode of travel and health impacts. Existing emission and dispersion models do not take direct account of the dynamic nature of traffic and how emissions impact the health of the diversity of urban dwellers, bus commuters, pedestrians, and bicycle riders. Typical approaches use highly aggregated vehicle data and computed link speeds to assign an emission factor to the traffic, an assumed proportion of which is trucks. In addition, existing methods to assess environmental impacts tend to focus on the production source of the pollutant not the impacts, which require information on population activities and its proximity to vehicle flows. Personal exposure studies document significant air quality impacts within the transportation microenvironment but do not integrate dynamic traffic and emission analysis. Previous research argues for a comprehensive approach. From the perspective of mitigating transportation impacts, it is significant to understand: a) exposure to the pollution, which in turn requires assessment of where people are in relation to the source of the pollutant, and b) the relation between pollution and vehicle flows. This research will target highly polluted high exposure hotspots in Portland, e.g. high traffic flows running through a major trip destination area for shopping, entertainment, education, or health care highly dependent on mode of travel, traffic levels and type, and built environment characteristics. Our approach is to conduct field studies to measure personal exposure to particulate matter as a function of transportation mode through pre-determined routes in the city. Exposure levels, position, time and rate of travel will be recorded. Simultaneously we will collect detailed traffic data that will provide type/number of vehicle, speed of travel and start/stop behavior. GIS analysis of the urban form and land use characteristics will establish built environment parameters. These data will be integrated into a built environment-travel mode-exposure model. The major scientific innovations offered by this project are: 1) integration of detailed and real-time exposure/emissions with a real-time traffic measurement approach, and 2) development of an integrated emissions and transportation model that combines traffic characteristics, emissions, built environment configuration, mode of travel and predicted health impacts. The outcomes of the research will be of importance to the general public, urban communities, departments of transportation charged with managing urban traffic, and public health authorities. Close