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• 21. [Article] Modeling and Analyzing the Impact of Advanced Technologies on Transit Performance Measures in Arterial Corridors

  Transportation and transit agencies have implemented advanced technologies like transit signal priority (TSP) and Sydney Coordinated Adaptive Traffic System (SCATS) to reduce travel times and improve reliability. ...

  Citation × Citation Citation Abstract Copy Title: Modeling and Analyzing the Impact of Advanced Technologies on Transit Performance Measures in Arterial Corridors Author: Figliozzi, Miguel A., Feng, Wei Year: 2014 Transportation and transit agencies have implemented advanced technologies like transit signal priority (TSP) and Sydney Coordinated Adaptive Traffic System (SCATS) to reduce travel times and improve reliability. However, due to the lack of detailed empirical data, the joint impact of these factors and improvement strategies on bus travel time has not been studied at the stop-to-stop segment level. With the aim of assessing the performance of an existing TSP/SCATS system, this study had access to a unique set of high-resolution bus and traffic signal data. Novel algorithms and performance measures to measure TSP performance are proposed. Results indicate that a timely and effective TSP system requires a high degree of sophistication, monitoring and maintenance. Empirical data suggest that most TSP phase adjustments were granted in time (i.e., within a cycle) to buses that requested priority, but that only a small proportion resulted in reduced delay. In this study, many green extension phases were granted late, making them less effective than early green signal phases. Despite this, the TSP system did not increase delays for passengers and vehicles when side-street traffic is also considered. Title: Modeling and Analyzing the Impact of Advanced Technologies on Transit Performance Measures in Arterial Corridors Author: Figliozzi, Miguel A., Feng, Wei Year: 2014 Transportation and transit agencies have implemented advanced technologies like transit signal priority (TSP) and Sydney Coordinated Adaptive Traffic System (SCATS) to reduce travel times and improve reliability. However, due to the lack of detailed empirical data, the joint impact of these factors and improvement strategies on bus travel time has not been studied at the stop-to-stop segment level. With the aim of assessing the performance of an existing TSP/SCATS system, this study had access to a unique set of high-resolution bus and traffic signal data. Novel algorithms and performance measures to measure TSP performance are proposed. Results indicate that a timely and effective TSP system requires a high degree of sophistication, monitoring and maintenance. Empirical data suggest that most TSP phase adjustments were granted in time (i.e., within a cycle) to buses that requested priority, but that only a small proportion resulted in reduced delay. In this study, many green extension phases were granted late, making them less effective than early green signal phases. Despite this, the TSP system did not increase delays for passengers and vehicles when side-street traffic is also considered. Close

• 22. [Article] 1988 Oregon Public Transportation Study

  Oregon continues to face challenges in public transportation. The lack of a consistent and comprehensive framework of state policy is making local efforts to meet public transportation demands harder and ...

  Citation × Citation Citation Abstract Copy Title: 1988 Oregon Public Transportation Study Author: Edner, Sheldon, Dueker, Kenneth, Dean, Janice Year: 1989 Oregon continues to face challenges in public transportation. The lack of a consistent and comprehensive framework of state policy is making local efforts to meet public transportation demands harder and fails to exploit economic and transportation opportunities for improving the vitality of the state. The absence of continuous and stable state financial assistance has weakened the state/local partnership in providing public transportation services and kept mobility for many Oregonians at a minimal level. Finally, as the federal role in funding transportation declines the need for aggressive state leadership increases. The following recommendations for Legislative and Executive action are offered as incremental steps towards meeting Oregon's public transportation challenge: Authorize additional funding for special needs transportation by increasing the revenues to the Special Transportation Fund. Authorize and fund an annual, stable capital assistance program for public transportation providers equivalent to the funding level of the past biennium. Provide greater flexibility of local public transportation option funding through authorization of new local revenue sources. Authorize and fund an expanded administrative role for the ODOT Public Transit Division to provide technical assistance, establish standards and monitor public transportation provider performance, administer state capital assistance to providers, and promote cooperation and coordination between transportation providers. Adopt as a statewide policy goal, cooperation among modal transportation agencies to achieve efficient and coordinated use of scarce resources. Adopt as a statewide policy goal, cooperation among public transportation programs and economic development programs in order to make Oregon an attractive and profitable location for industry. Adopt as a statewide policy goal, the coordination of services and resources among agencies that support public transportation and human service transportation. Create incentives for local land use guidelines that promote integration of transportation planning into existing and future land use policies. Title: 1988 Oregon Public Transportation Study Author: Edner, Sheldon, Dueker, Kenneth, Dean, Janice Year: 1989 Oregon continues to face challenges in public transportation. The lack of a consistent and comprehensive framework of state policy is making local efforts to meet public transportation demands harder and fails to exploit economic and transportation opportunities for improving the vitality of the state. The absence of continuous and stable state financial assistance has weakened the state/local partnership in providing public transportation services and kept mobility for many Oregonians at a minimal level. Finally, as the federal role in funding transportation declines the need for aggressive state leadership increases. The following recommendations for Legislative and Executive action are offered as incremental steps towards meeting Oregon's public transportation challenge: Authorize additional funding for special needs transportation by increasing the revenues to the Special Transportation Fund. Authorize and fund an annual, stable capital assistance program for public transportation providers equivalent to the funding level of the past biennium. Provide greater flexibility of local public transportation option funding through authorization of new local revenue sources. Authorize and fund an expanded administrative role for the ODOT Public Transit Division to provide technical assistance, establish standards and monitor public transportation provider performance, administer state capital assistance to providers, and promote cooperation and coordination between transportation providers. Adopt as a statewide policy goal, cooperation among modal transportation agencies to achieve efficient and coordinated use of scarce resources. Adopt as a statewide policy goal, cooperation among public transportation programs and economic development programs in order to make Oregon an attractive and profitable location for industry. Adopt as a statewide policy goal, the coordination of services and resources among agencies that support public transportation and human service transportation. Create incentives for local land use guidelines that promote integration of transportation planning into existing and future land use policies. Close

• 23. [Article] Accuracy of Bicycle Counting with Pneumatic Tubes in Oregon

  Interest in counting bicycles and establishing nonmotorized counting programs is increasing, but jurisdictions still struggle with how to integrate bicycle counting into standard practice. In this paper, ...

  Citation × Citation Citation Abstract Copy Title: Accuracy of Bicycle Counting with Pneumatic Tubes in Oregon Author: Nordback, Krista, Kothuri, Sirisha Murthy, Phillips, Taylor, Gorecki, Carson, Figliozzi, Miguel Year: 2016 Interest in counting bicycles and establishing nonmotorized counting programs is increasing, but jurisdictions still struggle with how to integrate bicycle counting into standard practice. In this paper, the authors share findings and recommendations for how to minimize error for bicycle counting from tests conducted in conjunction with the Oregon Department of Transportation. This research studied three types of off-the-shelf pneumatic tube counters for counting bicycles, including equipment from five manufacturers: two bicycle-specific counters, three varieties of motor vehicle classification counters, and one volume-only motor vehicle counter. Tests were conducted both in a controlled environment and in on-road mixed traffic to better identify problems in accuracy. Equipment studied generally undercounted cyclists, especially those in groups. Results from the controlled test with standard bicycles showed that within 10 ft of the counter, the undercounting error ranged from 0% to 212%. In the mixed-traffic test, all the equipment tested tended to undercount with mean percent error ranging from 210% to 273%. Each counter type has pros and cons, but in general, counting accuracy decreased with increases in bicycle and motor vehicle traffic and longer tube lengths. Higher accuracy can be achieved by careful selection of equipment type, classification scheme, and tube configuration. Bicycle speeds given by off-the-shelf pneumatic counting equipment were accurate. Title: Accuracy of Bicycle Counting with Pneumatic Tubes in Oregon Author: Nordback, Krista, Kothuri, Sirisha Murthy, Phillips, Taylor, Gorecki, Carson, Figliozzi, Miguel Year: 2016 Interest in counting bicycles and establishing nonmotorized counting programs is increasing, but jurisdictions still struggle with how to integrate bicycle counting into standard practice. In this paper, the authors share findings and recommendations for how to minimize error for bicycle counting from tests conducted in conjunction with the Oregon Department of Transportation. This research studied three types of off-the-shelf pneumatic tube counters for counting bicycles, including equipment from five manufacturers: two bicycle-specific counters, three varieties of motor vehicle classification counters, and one volume-only motor vehicle counter. Tests were conducted both in a controlled environment and in on-road mixed traffic to better identify problems in accuracy. Equipment studied generally undercounted cyclists, especially those in groups. Results from the controlled test with standard bicycles showed that within 10 ft of the counter, the undercounting error ranged from 0% to 212%. In the mixed-traffic test, all the equipment tested tended to undercount with mean percent error ranging from 210% to 273%. Each counter type has pros and cons, but in general, counting accuracy decreased with increases in bicycle and motor vehicle traffic and longer tube lengths. Higher accuracy can be achieved by careful selection of equipment type, classification scheme, and tube configuration. Bicycle speeds given by off-the-shelf pneumatic counting equipment were accurate. Close

• 24. [Article] Modeling the Impact of Traffic Conditions on the Variability of Mid-Block Roadside PM2.5 on an Urban Arterial

  Modeling Impact of Traffic Conditions on Variability of Midblock Roadside Fine Particulate Matter Concentrations on an Urban Arterial: This paper presents an innovative modeling of fine particulate matter ...

  Citation × Citation Citation Abstract Copy Title: Modeling the Impact of Traffic Conditions on the Variability of Mid-Block Roadside PM2.5 on an Urban Arterial Author: Moore, Adam Year: 2014 Modeling Impact of Traffic Conditions on Variability of Midblock Roadside Fine Particulate Matter Concentrations on an Urban Arterial: This paper presents an innovative modeling of fine particulate matter (PM2.5) concentrations as a function of very high resolution meteorological and traffic data. Peak period measurements were taken at a mid-block roadside location on an urban arterial commuter roadway. To capture the impact of dynamic traffic conditions, data were analyzed at 10-second intervals, with substantially higher resolution than typical roadside air quality study designs. Particular attention was paid to changes in traffic conditions, including fleet mix, queuing and vehicle platooning over the course of the study period, and the effect of these changes on PM2.5. Significant correlations were observed between vehicle platoons and increases in PM2.5 concentrations. Traffic state analysis was employed to determine median PM2.5 levels before and after the onset of congestion. A multivariate regression model was estimated to determine significant PM2.5 predictors while controlling for autocorrelation. Significance was found not only in the simultaneous traffic variables but also in lagged traffic variables; additionally, the effects of vehicle types and wind direction were quantified. Modeling results indicate that traffic conditions and vehicle type do have a significant impact on roadside PM2.5 concentrations. For instance, the addition of one heavy vehicle was shown to increase PM2.5 concentrations by 2.45% when wind blew across the roadway before reaching the monitoring location. This study serves as a demonstration of the abilities of very high resolution data to identify the effects of relatively minute changes in traffic conditions on air pollutant concentrations. Title: Modeling the Impact of Traffic Conditions on the Variability of Mid-Block Roadside PM2.5 on an Urban Arterial Author: Moore, Adam Year: 2014 Modeling Impact of Traffic Conditions on Variability of Midblock Roadside Fine Particulate Matter Concentrations on an Urban Arterial: This paper presents an innovative modeling of fine particulate matter (PM2.5) concentrations as a function of very high resolution meteorological and traffic data. Peak period measurements were taken at a mid-block roadside location on an urban arterial commuter roadway. To capture the impact of dynamic traffic conditions, data were analyzed at 10-second intervals, with substantially higher resolution than typical roadside air quality study designs. Particular attention was paid to changes in traffic conditions, including fleet mix, queuing and vehicle platooning over the course of the study period, and the effect of these changes on PM2.5. Significant correlations were observed between vehicle platoons and increases in PM2.5 concentrations. Traffic state analysis was employed to determine median PM2.5 levels before and after the onset of congestion. A multivariate regression model was estimated to determine significant PM2.5 predictors while controlling for autocorrelation. Significance was found not only in the simultaneous traffic variables but also in lagged traffic variables; additionally, the effects of vehicle types and wind direction were quantified. Modeling results indicate that traffic conditions and vehicle type do have a significant impact on roadside PM2.5 concentrations. For instance, the addition of one heavy vehicle was shown to increase PM2.5 concentrations by 2.45% when wind blew across the roadway before reaching the monitoring location. This study serves as a demonstration of the abilities of very high resolution data to identify the effects of relatively minute changes in traffic conditions on air pollutant concentrations. Close

• 25. [Article] Webinar: Developing Practical Dynamic Evaluation Methods for Transportation Structures

  Deteriorating transportation infrastructure is constantly in the news. Government agencies at all levels are pursuing methods to monitor structural health, so that they can prioritize repairs. In Oregon, ...

  Citation × Citation Citation Abstract Copy Title: Webinar: Developing Practical Dynamic Evaluation Methods for Transportation Structures Author: Riley, Charles Year: 2017 Deteriorating transportation infrastructure is constantly in the news. Government agencies at all levels are pursuing methods to monitor structural health, so that they can prioritize repairs. In Oregon, the Cascadia Subduction Zone megathrust earthquake looms as a significant natural hazard for which our transportation network is ill-prepared. The Oregon Department of Transportation (ODOT) estimates that it will take around $2.6 billion over seven years to repair or replace many of the existing bridges in the state’s network to maintain lifeline routes after a Cascadia event. Funding for the scenarios envisioned by ODOT is not forthcoming, and the project described in this webinar is aimed at creating a tool to support visual inspection of bridges for determining the extent of damage. The work presented in this webinar has evolved out of NITC-funded research and into a feasibility study of relatively simple but effective field methods for transportation structure dynamic evaluation. The primary driver for the methods under investigation is the advent of robust mobile apps that can process data from on-board accelerometers in real time. The goal of this work is to identify an easily deployed system to evaluate the dynamic response of a structure (commonly referred to as modal testing). Assuming such a system can be developed and deployed to record baseline data prior to the Cascadia event, the same system could be used after the event, or any significant event for that matter, to assist in determining if a structure has sustained damage that would limit its safe return to service. This webinar will describe the development and use of various tools for conducting modal testing in the field. After viewing the webinar, attendees should be able to: Describe the scale of the everyday and future hazards facing Oregon bridges Explain the relationship of structural parameters to dynamic response Describe a framework for conducting dynamic evaluation of structures to determine dominant modal frequencies Summarize the results of preliminary field studies using ambient traffic and forced vibration in conjunction with mobile-device based data acquisition Use mobile devices and apps to acquire acceleration data Title: Webinar: Developing Practical Dynamic Evaluation Methods for Transportation Structures Author: Riley, Charles Year: 2017 Deteriorating transportation infrastructure is constantly in the news. Government agencies at all levels are pursuing methods to monitor structural health, so that they can prioritize repairs. In Oregon, the Cascadia Subduction Zone megathrust earthquake looms as a significant natural hazard for which our transportation network is ill-prepared. The Oregon Department of Transportation (ODOT) estimates that it will take around $2.6 billion over seven years to repair or replace many of the existing bridges in the state’s network to maintain lifeline routes after a Cascadia event. Funding for the scenarios envisioned by ODOT is not forthcoming, and the project described in this webinar is aimed at creating a tool to support visual inspection of bridges for determining the extent of damage. The work presented in this webinar has evolved out of NITC-funded research and into a feasibility study of relatively simple but effective field methods for transportation structure dynamic evaluation. The primary driver for the methods under investigation is the advent of robust mobile apps that can process data from on-board accelerometers in real time. The goal of this work is to identify an easily deployed system to evaluate the dynamic response of a structure (commonly referred to as modal testing). Assuming such a system can be developed and deployed to record baseline data prior to the Cascadia event, the same system could be used after the event, or any significant event for that matter, to assist in determining if a structure has sustained damage that would limit its safe return to service. This webinar will describe the development and use of various tools for conducting modal testing in the field. After viewing the webinar, attendees should be able to: Describe the scale of the everyday and future hazards facing Oregon bridges Explain the relationship of structural parameters to dynamic response Describe a framework for conducting dynamic evaluation of structures to determine dominant modal frequencies Summarize the results of preliminary field studies using ambient traffic and forced vibration in conjunction with mobile-device based data acquisition Use mobile devices and apps to acquire acceleration data Close

• 26. [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

• 27. [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

• 28. [Article] Bicycle Level of Service: Where are the Gaps in Bicycle Flow Measures?

  Bicycle use is increasing in many parts of the U.S. Local and regional governments have set ambitious bicycle mode share goals as part of their strategy to curb greenhouse gas emissions and relieve traffic ...

  Citation × Citation Citation Abstract Copy Title: Bicycle Level of Service: Where are the Gaps in Bicycle Flow Measures? Author: Johnson, Pamela Christine Year: 2014 Bicycle use is increasing in many parts of the U.S. Local and regional governments have set ambitious bicycle mode share goals as part of their strategy to curb greenhouse gas emissions and relieve traffic congestion. In particular, Portland, Oregon has set a 25% mode share goal for 2030 (PBOT 2010). Currently bicycle mode share in Portland is 6.1% of all trips. Other cities and regional planning organizations are also setting ambitious bicycle mode share goals and increasing bicycle facilities and programs to encourage bicycling. Increases in bicycle mode share are being encouraged to increase. However, cities with higher-than-average bicycle mode share are beginning to experience locations with bicycle traffic congestion, especially during peak commute hours. Today, there are no established methods are used to describe or measure bicycle traffic flows. In the 1960s, the Highway Capacity Manual (HCM) introduced Level of Service (LOS) measurements to describe traffic flow and capacity of motor vehicles on highways using an A-to-F grading system; "A" describes free flow traffic with no maneuvering constraints for the driver and an "F" grade corresponds to over capacity situations in which traffic flow breaks down or becomes "jammed". LOS metrics were expanded to highway and road facilities, operations and design. In the 1990s, the HCM introduced LOS measurements for transit, pedestrians, and bicycles. Today, there are many well established and emerging bicycle level of service (BLOS) methods that measure the stress, comfort and perception of safety of bicycle facilities. However, it was been assumed that bicycle traffic volumes are low and do not warrant the use of a LOS measure for bicycle capacity and traffic flow. There are few BLOS methods that take bicycle flow into consideration, except for in the case of separated bicycle and bicycle-pedestrian paths. This thesis investigated the state of BLOS capacity methods that use bicycle volumes as a variable. The existing methods were applied to bicycle facility elements along a corridor that experiences high bicycle volumes in Portland, Oregon. Using data from the study corridor, BLOS was calculated and a sensitivity analysis was applied to each of the methods to determine how sensitive the models are to each of the variables used. An intercept survey was conducted to compare the BLOS capacity scores calculated for the corridor with the users' perception. In addition, 2030 bicycle mode share for the study corridor was estimated and the implications of increased future bicycle congestion were discussed. Gaps in the BLOS methods, limitations of the thesis study and future research were summarized. In general, the existing methods for BLOS capacity are intended for separated paths; they are not appropriate for existing high traffic flow facilities. Most of the BLOS traffic flow methods that have been developed are most sensitive to bicycle volumes. Some of these models may be a good starting point to improve BLOS capacity and traffic flow measures for high bicycle volume locations. Without the tools to measure and evaluate the patterns of bicycle capacity and traffic flow, it will be difficult to monitor and mitigate bicycle congestion and to plan for efficient bicycle facilities in the future. This report concludes that it is now time to develop new BLOS capacity measures that address bicycle traffic flow. Title: Bicycle Level of Service: Where are the Gaps in Bicycle Flow Measures? Author: Johnson, Pamela Christine Year: 2014 Bicycle use is increasing in many parts of the U.S. Local and regional governments have set ambitious bicycle mode share goals as part of their strategy to curb greenhouse gas emissions and relieve traffic congestion. In particular, Portland, Oregon has set a 25% mode share goal for 2030 (PBOT 2010). Currently bicycle mode share in Portland is 6.1% of all trips. Other cities and regional planning organizations are also setting ambitious bicycle mode share goals and increasing bicycle facilities and programs to encourage bicycling. Increases in bicycle mode share are being encouraged to increase. However, cities with higher-than-average bicycle mode share are beginning to experience locations with bicycle traffic congestion, especially during peak commute hours. Today, there are no established methods are used to describe or measure bicycle traffic flows. In the 1960s, the Highway Capacity Manual (HCM) introduced Level of Service (LOS) measurements to describe traffic flow and capacity of motor vehicles on highways using an A-to-F grading system; "A" describes free flow traffic with no maneuvering constraints for the driver and an "F" grade corresponds to over capacity situations in which traffic flow breaks down or becomes "jammed". LOS metrics were expanded to highway and road facilities, operations and design. In the 1990s, the HCM introduced LOS measurements for transit, pedestrians, and bicycles. Today, there are many well established and emerging bicycle level of service (BLOS) methods that measure the stress, comfort and perception of safety of bicycle facilities. However, it was been assumed that bicycle traffic volumes are low and do not warrant the use of a LOS measure for bicycle capacity and traffic flow. There are few BLOS methods that take bicycle flow into consideration, except for in the case of separated bicycle and bicycle-pedestrian paths. This thesis investigated the state of BLOS capacity methods that use bicycle volumes as a variable. The existing methods were applied to bicycle facility elements along a corridor that experiences high bicycle volumes in Portland, Oregon. Using data from the study corridor, BLOS was calculated and a sensitivity analysis was applied to each of the methods to determine how sensitive the models are to each of the variables used. An intercept survey was conducted to compare the BLOS capacity scores calculated for the corridor with the users' perception. In addition, 2030 bicycle mode share for the study corridor was estimated and the implications of increased future bicycle congestion were discussed. Gaps in the BLOS methods, limitations of the thesis study and future research were summarized. In general, the existing methods for BLOS capacity are intended for separated paths; they are not appropriate for existing high traffic flow facilities. Most of the BLOS traffic flow methods that have been developed are most sensitive to bicycle volumes. Some of these models may be a good starting point to improve BLOS capacity and traffic flow measures for high bicycle volume locations. Without the tools to measure and evaluate the patterns of bicycle capacity and traffic flow, it will be difficult to monitor and mitigate bicycle congestion and to plan for efficient bicycle facilities in the future. This report concludes that it is now time to develop new BLOS capacity measures that address bicycle traffic flow. Close

• 29. [Article] A Study of Headway Maintenance for Bus Routes: Causes and Effects of “Bus Bunching” in Extensive and Congested Service Areas

  A healthy and efficient public transit system is indispensable to reduce congestion, emissions, energy consumption, and car dependency in urban areas. The objective of this research is to 1) develop methods ...

  Citation × Citation Citation Abstract Copy Title: A Study of Headway Maintenance for Bus Routes: Causes and Effects of “Bus Bunching” in Extensive and Congested Service Areas Author: Figliozzi, Miguel A., Feng, Wu-chi, Lafferriere, Gerardo, Feng, Wei Year: 2012 A healthy and efficient public transit system is indispensable to reduce congestion, emissions, energy consumption, and car dependency in urban areas. The objective of this research is to 1) develop methods to evaluate and visualize bus service reliability for transit agencies in various temporal and spatial aggregation levels; 2) identify the recurrent unreliability trends of bus routes (focusing on high-frequency service periods) and understand their characteristics, causes and effects; and 3) model service times using linear regression models. This research utilized six months of archived automatic vehicle location (AVL) and automatic passenger count (APC) data from a low-performance route (Route 15) of TriMet, the public transit provider in the Portland metropolitan area. Route 15 has experienced difficulties in terms of schedule adherence and headway regularity. This research developed methods to summarize causes of bus bunching. We first determined the frequency of each cause (expressed as percentages) meeting pre-determined thresholds. Next, we performed a sensitivity analysis to demonstrate how cause percentage results change using varying difficulty levels of bus bunching thresholds. Finally, we investigated how cause percentage results vary spatially along different route segments. This research also developed novel ways to summarize and visualize vast amounts of bus route operations data in an insightful and intuitive manner: 1) a route/stop level visualization performance measure framework using color contour diagrams and 2) a dynamic interactive bus monitoring visualization framework based on a Google Maps platform. Visualizations proposed in this study can aid transit agency managers and operators to identify operational problems and better understand how such problems propagate spatially and temporally across routes. Finally, regression models were estimated to understand the key factors impacting dwell and travel times. Title: A Study of Headway Maintenance for Bus Routes: Causes and Effects of “Bus Bunching” in Extensive and Congested Service Areas Author: Figliozzi, Miguel A., Feng, Wu-chi, Lafferriere, Gerardo, Feng, Wei Year: 2012 A healthy and efficient public transit system is indispensable to reduce congestion, emissions, energy consumption, and car dependency in urban areas. The objective of this research is to 1) develop methods to evaluate and visualize bus service reliability for transit agencies in various temporal and spatial aggregation levels; 2) identify the recurrent unreliability trends of bus routes (focusing on high-frequency service periods) and understand their characteristics, causes and effects; and 3) model service times using linear regression models. This research utilized six months of archived automatic vehicle location (AVL) and automatic passenger count (APC) data from a low-performance route (Route 15) of TriMet, the public transit provider in the Portland metropolitan area. Route 15 has experienced difficulties in terms of schedule adherence and headway regularity. This research developed methods to summarize causes of bus bunching. We first determined the frequency of each cause (expressed as percentages) meeting pre-determined thresholds. Next, we performed a sensitivity analysis to demonstrate how cause percentage results change using varying difficulty levels of bus bunching thresholds. Finally, we investigated how cause percentage results vary spatially along different route segments. This research also developed novel ways to summarize and visualize vast amounts of bus route operations data in an insightful and intuitive manner: 1) a route/stop level visualization performance measure framework using color contour diagrams and 2) a dynamic interactive bus monitoring visualization framework based on a Google Maps platform. Visualizations proposed in this study can aid transit agency managers and operators to identify operational problems and better understand how such problems propagate spatially and temporally across routes. Finally, regression models were estimated to understand the key factors impacting dwell and travel times. Close

• 30. [Article] Maintaining Safe, Efficient and Sustainable Intermodal Transport Through the Port of Portland

  About $15 billion of freight passes annually through the Lower Columbia River (LCR) navigation channel to reach Portland and Vancouver, where most of it connects with land transport. This commerce plays ...

  Citation × Citation Citation Abstract Copy Title: Maintaining Safe, Efficient and Sustainable Intermodal Transport Through the Port of Portland Author: Jay, David A., Pan, Jiayi Year: 2011 About $15 billion of freight passes annually through the Lower Columbia River (LCR) navigation channel to reach Portland and Vancouver, where most of it connects with land transport. This commerce plays a vital role in sustaining the regional economy and connecting Oregon to the global economy. The timely connection of truck and rail transport with vessels is vital, especially for export traffic. This link is susceptible to disruption if water depths in the navigation channel are shallower than expected, leading to delays and/or draft limitations. Moreover, ship drafts have increased in recent decades, 25% of the vessels calling in the river sail with a draft close to the channel depth at low water, and these carry roughly 70% of the cargo. A large vessel may have as little as 0.6 m bed clearance when it passes through a low-tide point in the river, which each vessel in transit must do. Thus, prediction and real-time communication of water level to vessels is vital to safety as well as efficiency. This has been implemented through the LOADMAX system, consisting of telemetered water-level gauges and a forecast model. Moreover, the dilemma has been made more critical by changes in the river – low water levels in the river channel between Wauna and Vancouver have decreased 0.3-1.2 m since 1940. The rate of decrease depends on location and riverflow, but appears to have accelerated in the last decade. The reasons for this decrease are not understood. For perspective, an ongoing 0.9 m channel deepening will cost about $150 million when completed, so unintended decreases in water depths are expensive as well as potentially dangerous. Lower water levels in the river also increase carbon emissions, because smaller loads mean more land and vessel transport trips. Further, navigation and salmon habitat restoration are closely connected. Dredging is used to maintain the channel, and habitat restoration is an integral part of the channel deepening. New dredging strategies are needed to maintain the newly deepened channel, but dredging that removes material permanently from the river may, further lower water levels, limiting possibilities for habitat restoration and reducing bed clearance for large ships. These problems will be exacerbated by future decreases in summer river flows due to climate change. Title: Maintaining Safe, Efficient and Sustainable Intermodal Transport Through the Port of Portland Author: Jay, David A., Pan, Jiayi Year: 2011 About $15 billion of freight passes annually through the Lower Columbia River (LCR) navigation channel to reach Portland and Vancouver, where most of it connects with land transport. This commerce plays a vital role in sustaining the regional economy and connecting Oregon to the global economy. The timely connection of truck and rail transport with vessels is vital, especially for export traffic. This link is susceptible to disruption if water depths in the navigation channel are shallower than expected, leading to delays and/or draft limitations. Moreover, ship drafts have increased in recent decades, 25% of the vessels calling in the river sail with a draft close to the channel depth at low water, and these carry roughly 70% of the cargo. A large vessel may have as little as 0.6 m bed clearance when it passes through a low-tide point in the river, which each vessel in transit must do. Thus, prediction and real-time communication of water level to vessels is vital to safety as well as efficiency. This has been implemented through the LOADMAX system, consisting of telemetered water-level gauges and a forecast model. Moreover, the dilemma has been made more critical by changes in the river – low water levels in the river channel between Wauna and Vancouver have decreased 0.3-1.2 m since 1940. The rate of decrease depends on location and riverflow, but appears to have accelerated in the last decade. The reasons for this decrease are not understood. For perspective, an ongoing 0.9 m channel deepening will cost about $150 million when completed, so unintended decreases in water depths are expensive as well as potentially dangerous. Lower water levels in the river also increase carbon emissions, because smaller loads mean more land and vessel transport trips. Further, navigation and salmon habitat restoration are closely connected. Dredging is used to maintain the channel, and habitat restoration is an integral part of the channel deepening. New dredging strategies are needed to maintain the newly deepened channel, but dredging that removes material permanently from the river may, further lower water levels, limiting possibilities for habitat restoration and reducing bed clearance for large ships. These problems will be exacerbated by future decreases in summer river flows due to climate change. Close