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• 1. [Article] Oregon Freight Data Mart

  Increasing freight volumes are adding pressure to the Oregon transportation system. Monitoring the performance of the transportation system and freight movements is essential to guarantee the economic ...

  Citation × Citation Citation Abstract Copy Title: Oregon Freight Data Mart Author: Figliozzi, Miguel, Bertini, Robert Year: 2010 Increasing freight volumes are adding pressure to the Oregon transportation system. Monitoring the performance of the transportation system and freight movements is essential to guarantee the economic development of the region, the efficient allocation of resources, and the quality of life of all Oregonians. Freight data is expensive to collect and maintain. Confidentiality issues, the size of the datasets, and the complexity of freight movements are barriers that preclude the easy access and analysis of freight data. Data accessibility and integration is essential to ensure successful freight planning and consistency across regional partner agencies and planning organizations. In relation to Internet-based mapping technology in freight data collection and planning, the main objectives of this project are: (a) address implementation issues associated with data integration, (b) present a system architecture to leverage existing publically-available interfaces and web applications to accelerate product development and reduce costs, (c) describe an existing web-based mapping prototype and its capabilities, (d) state lessons learned and present suggestions to streamline the integration and visualization of freight data, and (e) discuss load-time and display quality issues associated with the visualization of transportation data on internet-based mapping applications. The strategies and methodologies described in this report are equally applicable to the display of areas such as states or counties as well as linear data such linear data such as highways, waterways, and railways. Despite data integration challenges, Internet-based mapping provides a cost effective and appealing tool to store, access, and communicate freight data as well as enhance our understanding of freight issues. Institutional barriers, not technology, are the most demanding hurdles to widely implementing a freight data web-based mapping application in the near future. Title: Oregon Freight Data Mart Author: Figliozzi, Miguel, Bertini, Robert Year: 2010 Increasing freight volumes are adding pressure to the Oregon transportation system. Monitoring the performance of the transportation system and freight movements is essential to guarantee the economic development of the region, the efficient allocation of resources, and the quality of life of all Oregonians. Freight data is expensive to collect and maintain. Confidentiality issues, the size of the datasets, and the complexity of freight movements are barriers that preclude the easy access and analysis of freight data. Data accessibility and integration is essential to ensure successful freight planning and consistency across regional partner agencies and planning organizations. In relation to Internet-based mapping technology in freight data collection and planning, the main objectives of this project are: (a) address implementation issues associated with data integration, (b) present a system architecture to leverage existing publically-available interfaces and web applications to accelerate product development and reduce costs, (c) describe an existing web-based mapping prototype and its capabilities, (d) state lessons learned and present suggestions to streamline the integration and visualization of freight data, and (e) discuss load-time and display quality issues associated with the visualization of transportation data on internet-based mapping applications. The strategies and methodologies described in this report are equally applicable to the display of areas such as states or counties as well as linear data such linear data such as highways, waterways, and railways. Despite data integration challenges, Internet-based mapping provides a cost effective and appealing tool to store, access, and communicate freight data as well as enhance our understanding of freight issues. Institutional barriers, not technology, are the most demanding hurdles to widely implementing a freight data web-based mapping application in the near future. Close

• 2. [Article] Improving Travel Information Products via Robust Estimation Techniques

  Traffic-monitoring systems, such as those using loop detectors, are prone to coverage gaps, arising from sensor noise, processing errors and transmission problems. Such gaps adversely affect the accuracy ...

  Citation × Citation Citation Abstract Copy Title: Improving Travel Information Products via Robust Estimation Techniques Author: Maier, David, Tufte, Kristin A., Fernández Moctezuma, Rafael J. Year: 2009 Traffic-monitoring systems, such as those using loop detectors, are prone to coverage gaps, arising from sensor noise, processing errors and transmission problems. Such gaps adversely affect the accuracy of Advanced Traveler Information Systems. This project will explore models based on historical data that can provide estimates to fill such gaps. We build on an initial study by Mr. Rafael J. Fernandez-Moctezuma, using both a linear model and an artificial neural network (ANN) trained on historical data to estimate values for reporting gaps. These initial models were 80% and 89% accurate, respectively, in estimating the correct speed range, and misclassifications were always between adjacent speed ranges (in particular, the free-flow range and congested range were never confused). Going forward, we will investigate other non-linear models, such as Gaussian Mixtures, that provide further statistical metrics, in contrast to the uninterpreted weights of ANNs. This work will exploit the Portland Transportation Archive Listing (PORTAL) at the Intelligent Transportation Systems Laboratory at PSU. Dr. Tufte helps supervise development of PORTAL, and Mr. Fernandez used PORTAL data in his study. PORTAL holds more than two years of Portland-area freeway-loop-detector data at both detailed and aggregated levels, and is an ideal resource for the proposed work. Initially we will be building and testing estimators in off-line mode. We will select a highway segment (comprising multiple detector stations) that is representative in terms of pattern of outages. We will build models for this segment, then examine their performance on estimates for synthetic gaps (so we can compare estimates to reported values). Later, using live loop-detector data (which PORTAL supports), we will work towards on-line estimation over the local freeway network, which requires computing estimates in a timely manner. Our end target is improvements in end-user travel information products, such as the Portland-Metro Speed Map on ODOT's Trip Check. Our main evaluation metric will be the trade-off curve bewteen accuracy of prediciton and percentage of gaps that can be filled. This research supports national surface-transportation research priorities, including the Systems Management Information area (ITS JPO). Within that area, it relates to (2) Data Management (techniques and guidance for processing and managing data associated with highway and transit monitoring) and (5) Data Dissemination (exchanging information about transportation services and providing that information to travelers). [Page 3-15, U.S. Department of Transportation Research, Development, and Technology Plan, 6th Edition] Title: Improving Travel Information Products via Robust Estimation Techniques Author: Maier, David, Tufte, Kristin A., Fernández Moctezuma, Rafael J. Year: 2009 Traffic-monitoring systems, such as those using loop detectors, are prone to coverage gaps, arising from sensor noise, processing errors and transmission problems. Such gaps adversely affect the accuracy of Advanced Traveler Information Systems. This project will explore models based on historical data that can provide estimates to fill such gaps. We build on an initial study by Mr. Rafael J. Fernandez-Moctezuma, using both a linear model and an artificial neural network (ANN) trained on historical data to estimate values for reporting gaps. These initial models were 80% and 89% accurate, respectively, in estimating the correct speed range, and misclassifications were always between adjacent speed ranges (in particular, the free-flow range and congested range were never confused). Going forward, we will investigate other non-linear models, such as Gaussian Mixtures, that provide further statistical metrics, in contrast to the uninterpreted weights of ANNs. This work will exploit the Portland Transportation Archive Listing (PORTAL) at the Intelligent Transportation Systems Laboratory at PSU. Dr. Tufte helps supervise development of PORTAL, and Mr. Fernandez used PORTAL data in his study. PORTAL holds more than two years of Portland-area freeway-loop-detector data at both detailed and aggregated levels, and is an ideal resource for the proposed work. Initially we will be building and testing estimators in off-line mode. We will select a highway segment (comprising multiple detector stations) that is representative in terms of pattern of outages. We will build models for this segment, then examine their performance on estimates for synthetic gaps (so we can compare estimates to reported values). Later, using live loop-detector data (which PORTAL supports), we will work towards on-line estimation over the local freeway network, which requires computing estimates in a timely manner. Our end target is improvements in end-user travel information products, such as the Portland-Metro Speed Map on ODOT's Trip Check. Our main evaluation metric will be the trade-off curve bewteen accuracy of prediciton and percentage of gaps that can be filled. This research supports national surface-transportation research priorities, including the Systems Management Information area (ITS JPO). Within that area, it relates to (2) Data Management (techniques and guidance for processing and managing data associated with highway and transit monitoring) and (5) Data Dissemination (exchanging information about transportation services and providing that information to travelers). [Page 3-15, U.S. Department of Transportation Research, Development, and Technology Plan, 6th Edition] Close

• 3. [Article] Continuous Data Integration for Land Use and Transportation Planning and Modeling

  There is an urgent need for improved models that address the interdependencies between land use and transportation, and considerable new work is underway to develop such models in Oregon and elsewhere. ...

  Citation × Citation Citation Abstract Copy Title: Continuous Data Integration for Land Use and Transportation Planning and Modeling Author: Wang, Liming, Kim, Kihong Year: 2014 There is an urgent need for improved models that address the interdependencies between land use and transportation, and considerable new work is underway to develop such models in Oregon and elsewhere. These models and planning practices to integrate land use into the process, however, require the integration of massive amounts of land use data that is messy and incomplete. There have been considerable advances in the treatment of such data problems in other domains, drawing on data mining and machine-learning techniques to address issues in various domains. To date, however, little systematic effort has applied these technological advances to the problem domain of land use and transportation data. Experience suggests that as much as 70% of the total effort in developing integrated land use and transportation models is directly or indirectly associated with data development, integration and cleaning, yet there is remarkably little systematic research focused on the development of reusable methods and tools to support this problem domain. In coordination with an ongoing project of similar theme funded by University of California Transportation Center (UCTC), this project will focus on bringing interdisciplinary methods to develop land use datasets for integrated land use and transportation planning and modeling, with special attention on preserving temporal dimension of the data and monitoring data quality through indicators. Utilizing statistics and machine-learning techniques, we will develop reusable tools that will create a harmonized and coherent land use database from various public and private sources. These tools will be made available to the public and can be used by cities, counties, metropolitan planning agencies, state agencies, universities or anyone else needing to develop a usable database for use in integrated planning and modeling. All of the resulting data, with the exception of proprietary or confidential input data where there is no viable alternative, would be public and reusable for planning and research. Title: Continuous Data Integration for Land Use and Transportation Planning and Modeling Author: Wang, Liming, Kim, Kihong Year: 2014 There is an urgent need for improved models that address the interdependencies between land use and transportation, and considerable new work is underway to develop such models in Oregon and elsewhere. These models and planning practices to integrate land use into the process, however, require the integration of massive amounts of land use data that is messy and incomplete. There have been considerable advances in the treatment of such data problems in other domains, drawing on data mining and machine-learning techniques to address issues in various domains. To date, however, little systematic effort has applied these technological advances to the problem domain of land use and transportation data. Experience suggests that as much as 70% of the total effort in developing integrated land use and transportation models is directly or indirectly associated with data development, integration and cleaning, yet there is remarkably little systematic research focused on the development of reusable methods and tools to support this problem domain. In coordination with an ongoing project of similar theme funded by University of California Transportation Center (UCTC), this project will focus on bringing interdisciplinary methods to develop land use datasets for integrated land use and transportation planning and modeling, with special attention on preserving temporal dimension of the data and monitoring data quality through indicators. Utilizing statistics and machine-learning techniques, we will develop reusable tools that will create a harmonized and coherent land use database from various public and private sources. These tools will be made available to the public and can be used by cities, counties, metropolitan planning agencies, state agencies, universities or anyone else needing to develop a usable database for use in integrated planning and modeling. All of the resulting data, with the exception of proprietary or confidential input data where there is no viable alternative, would be public and reusable for planning and research. Close

• 4. [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

• 5. [Article] Multimodal Data at Signalized Intersections: Strategies for Archiving Existing and New Data Streams to Support Operations and Planning & Fusion and Integration of Arterial Performance Data

  There is a growing interest in arterial system management due to the increasing amount of travel on arterials and a growing emphasis on multimodal transportation. The benefits of archiving arterial-related ...

  Citation × Citation Citation Abstract Copy Title: Multimodal Data at Signalized Intersections: Strategies for Archiving Existing and New Data Streams to Support Operations and Planning & Fusion and Integration of Arterial Performance Data Author: Tufte, Kristin A., Monsere, Christopher M., Kothuri, Sirisha Murthy, Olson, Carl Scott Year: 2013 There is a growing interest in arterial system management due to the increasing amount of travel on arterials and a growing emphasis on multimodal transportation. The benefits of archiving arterial-related data are numerous. This research report describes our efforts to assemble and develop a multimodal archive for the Portland-Vancouver region. There is coverage of data sources from all modes in the metropolitan region; however, the preliminary nature of the archiving process means that some of the data are incomplete and samples. The arterial data sources available in the Portland-Vancouver region and that are covered in this report include data for various local agencies (City of Portland, Clark County, WA, TriMet and C-TRAN) covering vehicle, transit, pedestrian, and bicycle modes. We provide detailed descriptions of each data source and a spatial and temporal classification. The report describes the conceptual framework for an archive and the data collection and archival process, including the process for extracting the data from the agency systems and transferring these data to our multimodal database. Data can be made more useful though the use of improved visualization techniques. Thus as part of the project, a number of novel, online visualizations were created and implemented. These graphs and displays are summarized in this report and example visualizations are shown. As with any automated sensor system, data quality and completeness is an important issue and the challenge of automating data quality is large. Preliminary efforts to validate and monitor data quality and automate data quality processing are explored. Finally, the report presents efforts to combine transit and travel time data and signal timing and vehicle count data to generate some sample congestion measures. Title: Multimodal Data at Signalized Intersections: Strategies for Archiving Existing and New Data Streams to Support Operations and Planning & Fusion and Integration of Arterial Performance Data Author: Tufte, Kristin A., Monsere, Christopher M., Kothuri, Sirisha Murthy, Olson, Carl Scott Year: 2013 There is a growing interest in arterial system management due to the increasing amount of travel on arterials and a growing emphasis on multimodal transportation. The benefits of archiving arterial-related data are numerous. This research report describes our efforts to assemble and develop a multimodal archive for the Portland-Vancouver region. There is coverage of data sources from all modes in the metropolitan region; however, the preliminary nature of the archiving process means that some of the data are incomplete and samples. The arterial data sources available in the Portland-Vancouver region and that are covered in this report include data for various local agencies (City of Portland, Clark County, WA, TriMet and C-TRAN) covering vehicle, transit, pedestrian, and bicycle modes. We provide detailed descriptions of each data source and a spatial and temporal classification. The report describes the conceptual framework for an archive and the data collection and archival process, including the process for extracting the data from the agency systems and transferring these data to our multimodal database. Data can be made more useful though the use of improved visualization techniques. Thus as part of the project, a number of novel, online visualizations were created and implemented. These graphs and displays are summarized in this report and example visualizations are shown. As with any automated sensor system, data quality and completeness is an important issue and the challenge of automating data quality is large. Preliminary efforts to validate and monitor data quality and automate data quality processing are explored. Finally, the report presents efforts to combine transit and travel time data and signal timing and vehicle count data to generate some sample congestion measures. Close

• 6. [Article] Assessment and Refinement of Real-Time Travel Time Algorithms for Use in Practice

  The Federal Highway Administration (FHWA) has set a high priority on the use of existing dynamic message signs (DMS) to provide travel time estimates to the public. The Oregon Department of Transportation ...

  Citation × Citation Citation Abstract Copy Title: Assessment and Refinement of Real-Time Travel Time Algorithms for Use in Practice Author: Tufte, Kristin A., Kothuri, Sirisha Murthy Year: 2008 The Federal Highway Administration (FHWA) has set a high priority on the use of existing dynamic message signs (DMS) to provide travel time estimates to the public. The Oregon Department of Transportation (ODOT) currently has three DMS in the Portland metropolitan area configured to display travel time information. In the near future, ODOT would like to make travel time estimates available on additional DMS, over the Internet on tripcheck.com and via 511. Travel time estimates are valuable to the traveling public; however, the estimates must be accurate to be useful. The FHWA indicates that 90% accuracy is ideal and suggests a minimum accuracy of 80%. Thus, in order to display travel time estimates, it is essential to understand the accuracy of the estimates. The purpose of this study is to extend prior travel time research conducted at Portland State University with additional data collection and analysis to provide statistical confidence in travel time estimates and to determine the best travel time estimation approach for ODOT. Ground truth data in the form of probe vehicle runs will be collected and travel time estimates will be evaluated using that data. Several travel time estimation algorithms will be evaluated and modifications to existing algorithms will be proposed. In addition, this project will provide analysis to help understand the reliability and performance of the algorithms under various conditions (free-flow, congestion, incidents). A methodology will be developed for determining if travel time estimates fall within an acceptable accuracy limits. At the conclusion of the project, it is desired that a methodology can be recommended that will provide accurate measures of travel time for use with DMS, the Internet and 511 applications. Title: Assessment and Refinement of Real-Time Travel Time Algorithms for Use in Practice Author: Tufte, Kristin A., Kothuri, Sirisha Murthy Year: 2008 The Federal Highway Administration (FHWA) has set a high priority on the use of existing dynamic message signs (DMS) to provide travel time estimates to the public. The Oregon Department of Transportation (ODOT) currently has three DMS in the Portland metropolitan area configured to display travel time information. In the near future, ODOT would like to make travel time estimates available on additional DMS, over the Internet on tripcheck.com and via 511. Travel time estimates are valuable to the traveling public; however, the estimates must be accurate to be useful. The FHWA indicates that 90% accuracy is ideal and suggests a minimum accuracy of 80%. Thus, in order to display travel time estimates, it is essential to understand the accuracy of the estimates. The purpose of this study is to extend prior travel time research conducted at Portland State University with additional data collection and analysis to provide statistical confidence in travel time estimates and to determine the best travel time estimation approach for ODOT. Ground truth data in the form of probe vehicle runs will be collected and travel time estimates will be evaluated using that data. Several travel time estimation algorithms will be evaluated and modifications to existing algorithms will be proposed. In addition, this project will provide analysis to help understand the reliability and performance of the algorithms under various conditions (free-flow, congestion, incidents). A methodology will be developed for determining if travel time estimates fall within an acceptable accuracy limits. At the conclusion of the project, it is desired that a methodology can be recommended that will provide accurate measures of travel time for use with DMS, the Internet and 511 applications. Close

• 7. [Article] Analysis of Bus Collision Incidents Using Transit ITS and other Archived Operations Data

  This report analyzes factors contributing to bus operations safety incidents at TriMet, the transit provider for the Portland Oregon metropolitan region. The analysis focuses on 4,631 collision and non-collision ...

  Citation × Citation Citation Abstract Copy Title: Analysis of Bus Collision Incidents Using Transit ITS and other Archived Operations Data Author: Strathman, James G., Wachana, Paul Herman, Callas, Steve Year: 2010 This report analyzes factors contributing to bus operations safety incidents at TriMet, the transit provider for the Portland Oregon metropolitan region. The analysis focuses on 4,631 collision and non-collision incidents that occurred between 2006 and 2009. Empirical analysis of these incidents draws on a wide array of operator-level data recovered by transit ITS technologies in combination with information from TriMet’s human resources, scheduling, and customer relations databases. Incident frequencies are estimated in relation to operators’ demographic characteristics, employment status, assigned work characteristics, service delivery and performance indicators, temporal factors, and customer information. Apart from identifying factors that are empirically related to the frequency of safety incidents, the findings offer insights into operations policies and practices that hold promise for improving safety. Title: Analysis of Bus Collision Incidents Using Transit ITS and other Archived Operations Data Author: Strathman, James G., Wachana, Paul Herman, Callas, Steve Year: 2010 This report analyzes factors contributing to bus operations safety incidents at TriMet, the transit provider for the Portland Oregon metropolitan region. The analysis focuses on 4,631 collision and non-collision incidents that occurred between 2006 and 2009. Empirical analysis of these incidents draws on a wide array of operator-level data recovered by transit ITS technologies in combination with information from TriMet’s human resources, scheduling, and customer relations databases. Incident frequencies are estimated in relation to operators’ demographic characteristics, employment status, assigned work characteristics, service delivery and performance indicators, temporal factors, and customer information. Apart from identifying factors that are empirically related to the frequency of safety incidents, the findings offer insights into operations policies and practices that hold promise for improving safety. Close

• 8. [Article] Spatial variations in the intra-urban response to a noise source

  Most research on the urban sonic environment has been recent. One finding has been that physical noise exposure indices calibrate poorly with human noise response. The vagaries of human response to noise ...

  Citation × Citation Citation Abstract Copy Title: Spatial variations in the intra-urban response to a noise source Author: Conder, Wilbur David Year: 1973 Most research on the urban sonic environment has been recent. One finding has been that physical noise exposure indices calibrate poorly with human noise response. The vagaries of human response to noise have given impetus to research to isolate the factors that differentiate human response to noise. The present thesis continues this research. The thesis specifies human noise response to occur on three levels: awareness, annoyance, and complaint. The factors that structure each level of noise response are identified in the published Iiterature. Noise awareness is a function of noise exposure. Noise annoyance is a function of noise exposure to a lesser degree. In addition annoyance is structured by attitudes toward the noise source, special interests in its economic benefits and personal susceptibility to noise irritation. Complaint concerning noise involves the previous factors plus an affluence or socio-economic component. The trend as one moves upward in the noise response hierarchy is for the structuring factors to become specific to individuals rather than location. Hence, noise awareness with respect to a stationary noise source will vary spatially, while complaint will be random in space. In testing these premises the author has made use of noise exposure indices for Portland International Airport and a social survey of response in the area surrounding the airport. The noise exposure indices were supplied by the consulting firm of Bolt, Beranek, and Newman Inc. and the social survey was conducted and tabulated by the Center for Population Research and Census at Portland State University. Multivariate methods were used for testing the premises concerning the hierarchical relationships between awareness, annoyance, and complaint.The variables representing awareness, annoyance, and complaint are quantified from the survey data through principle component and factor scores computer programs. The noise awareness measure is selected for greatest emphasis since it underlies to annoyance and complaint. The noise awareness measure is investigated and errors in its measurement are estimated through psychometric methods. Trend surface techniques are used to test the spatial regularity of awareness, annoyance, and complaint. As hypothesized, awareness is regular in space, annoyance less so, and complaint is random. Through multiple regression analysis noise awareness is tested against socio-economic measures, noise exposure measures, attitudes, and special interest. Noise exposure variables account for the largest part of the variation in noise awareness. A trend surface analysis is conducted on the values of awareness predicted by a large number of exposure, attitude, and other variables. The process is repeated for the residual values from the multiple regression. Predicted values are systematic in space but the residual values are largely random. The predicted values are mapped and compared with the actual smoothed awareness response surface. The two maps correspond well. It is concluded that noise exposure corrected for ambient noise levels adequately approximates the noise awareness response surface. Title: Spatial variations in the intra-urban response to a noise source Author: Conder, Wilbur David Year: 1973 Most research on the urban sonic environment has been recent. One finding has been that physical noise exposure indices calibrate poorly with human noise response. The vagaries of human response to noise have given impetus to research to isolate the factors that differentiate human response to noise. The present thesis continues this research. The thesis specifies human noise response to occur on three levels: awareness, annoyance, and complaint. The factors that structure each level of noise response are identified in the published Iiterature. Noise awareness is a function of noise exposure. Noise annoyance is a function of noise exposure to a lesser degree. In addition annoyance is structured by attitudes toward the noise source, special interests in its economic benefits and personal susceptibility to noise irritation. Complaint concerning noise involves the previous factors plus an affluence or socio-economic component. The trend as one moves upward in the noise response hierarchy is for the structuring factors to become specific to individuals rather than location. Hence, noise awareness with respect to a stationary noise source will vary spatially, while complaint will be random in space. In testing these premises the author has made use of noise exposure indices for Portland International Airport and a social survey of response in the area surrounding the airport. The noise exposure indices were supplied by the consulting firm of Bolt, Beranek, and Newman Inc. and the social survey was conducted and tabulated by the Center for Population Research and Census at Portland State University. Multivariate methods were used for testing the premises concerning the hierarchical relationships between awareness, annoyance, and complaint.The variables representing awareness, annoyance, and complaint are quantified from the survey data through principle component and factor scores computer programs. The noise awareness measure is selected for greatest emphasis since it underlies to annoyance and complaint. The noise awareness measure is investigated and errors in its measurement are estimated through psychometric methods. Trend surface techniques are used to test the spatial regularity of awareness, annoyance, and complaint. As hypothesized, awareness is regular in space, annoyance less so, and complaint is random. Through multiple regression analysis noise awareness is tested against socio-economic measures, noise exposure measures, attitudes, and special interest. Noise exposure variables account for the largest part of the variation in noise awareness. A trend surface analysis is conducted on the values of awareness predicted by a large number of exposure, attitude, and other variables. The process is repeated for the residual values from the multiple regression. Predicted values are systematic in space but the residual values are largely random. The predicted values are mapped and compared with the actual smoothed awareness response surface. The two maps correspond well. It is concluded that noise exposure corrected for ambient noise levels adequately approximates the noise awareness response surface. Close

• 9. [Article] Diurnal and Seasonal Variations of NO, NO2 and PM2.5 Mass as a Function of Traffic Volumes Alongside an Urban Arterial

  Urban arterial corridors are landscapes that give rise to short and long-term exposures to transportation-related pollution. With high traffic volumes and a wide mix of road users, urban arterial environments ...

  Citation × Citation Citation Abstract Copy Title: Diurnal and Seasonal Variations of NO, NO2 and PM2.5 Mass as a Function of Traffic Volumes Alongside an Urban Arterial Author: Kendrick, Christine M., Koonce, Peter, George, Linda A. Year: 2015 Urban arterial corridors are landscapes that give rise to short and long-term exposures to transportation-related pollution. With high traffic volumes and a wide mix of road users, urban arterial environments are important targets for improved exposure assessment to traffic-related pollution. A common method to estimate exposure is to use traffic volumes as a proxy. The study presented here analyzes a unique yearlong dataset of simultaneous roadside air quality and traffic observations for a U.S. arterial to assess the reliability of using traffic volumes as a proxy for traffic-related exposure. Results show how the relationships of traffic volumes with NO and NO2 vary not only by time of day and season but also by time aggregation. At short-term aggregations (15 minutes) nitrogen oxides were found to have a significant linear relationship with traffic volumes during morning hours for all seasons although variability was still high (r2= 0.1 - 0.45 NO, r2=0.14 - 0.27 NO2), and little to no relationship during evening periods (r222). Comparisons with coarse annual results validate the use of traffic volumes to estimate annual exposure concentrations for morning periods (r2= 0.89 NO, r2=0.87 NO2) and evening NO2 (r2=0.46). Traffic volumes are a weak or poor predictor for annual evening NO (r2= -0.09) and short-term 15 minute aggregations. Seasonal and diurnal characterizations show that roadside PM2.5 (mass) measurements do not have a relationship with local traffic volumes, leading us to conclude that PM2.5 mass is more tied to regional sources and meteorological conditions. As epidemiology and personal exposure assessment research aims to study health impacts and pollutant levels encountered by pedestrians, bicyclists, those waiting for transit, and other road users, these results show when traffic volumes alone can be a reliable proxy for exposure and when this approach is not warranted. Title: Diurnal and Seasonal Variations of NO, NO2 and PM2.5 Mass as a Function of Traffic Volumes Alongside an Urban Arterial Author: Kendrick, Christine M., Koonce, Peter, George, Linda A. Year: 2015 Urban arterial corridors are landscapes that give rise to short and long-term exposures to transportation-related pollution. With high traffic volumes and a wide mix of road users, urban arterial environments are important targets for improved exposure assessment to traffic-related pollution. A common method to estimate exposure is to use traffic volumes as a proxy. The study presented here analyzes a unique yearlong dataset of simultaneous roadside air quality and traffic observations for a U.S. arterial to assess the reliability of using traffic volumes as a proxy for traffic-related exposure. Results show how the relationships of traffic volumes with NO and NO2 vary not only by time of day and season but also by time aggregation. At short-term aggregations (15 minutes) nitrogen oxides were found to have a significant linear relationship with traffic volumes during morning hours for all seasons although variability was still high (r2= 0.1 - 0.45 NO, r2=0.14 - 0.27 NO2), and little to no relationship during evening periods (r222). Comparisons with coarse annual results validate the use of traffic volumes to estimate annual exposure concentrations for morning periods (r2= 0.89 NO, r2=0.87 NO2) and evening NO2 (r2=0.46). Traffic volumes are a weak or poor predictor for annual evening NO (r2= -0.09) and short-term 15 minute aggregations. Seasonal and diurnal characterizations show that roadside PM2.5 (mass) measurements do not have a relationship with local traffic volumes, leading us to conclude that PM2.5 mass is more tied to regional sources and meteorological conditions. As epidemiology and personal exposure assessment research aims to study health impacts and pollutant levels encountered by pedestrians, bicyclists, those waiting for transit, and other road users, these results show when traffic volumes alone can be a reliable proxy for exposure and when this approach is not warranted. Close

• 10. [Article] Tri-Met's Experience With Automatic Passenger Counter and Automatic Vehicle Location Systems

  The Tri-County Metropolitan Transportation District of Oregon (Tri-Met) is one of about 30 metropolitan transit agencies that have deployed both automatic vehicle location (AVL) and automatic passenger ...

  Citation × Citation Citation Abstract Copy Title: Tri-Met's Experience With Automatic Passenger Counter and Automatic Vehicle Location Systems Author: Strathman, James G. Year: 2002 The Tri-County Metropolitan Transportation District of Oregon (Tri-Met) is one of about 30 metropolitan transit agencies that have deployed both automatic vehicle location (AVL) and automatic passenger counter (APC) systems (Casey, 1999). These technologies are important components of the agency’s new automated bus dispatching system (BDS). The AVL and APC systems at Tri-Met recover comprehensive operations and passenger activity data at the bus stop level that is archived for later analysis. The agency has gained a reputation as an industry leader in the areas of data archiving and the application of archived data to performance monitoring and analysis. Prior to the implementation of AVL and APC technology, Tri-Met, like others in the transit industry, relied on costly manual data recovery. During lean budget years in the early 1980s, the agency began using stand-alone APCs instead of ride checkers, and recovered very little operating data beyond what was required for Federal Transit Administration reporting. With its AVL and APC systems, Tri-Met is now automatically collecting and archiving over 500,000 stop and event data records per day. Offline analysis of this data supports a wide array of agency activities. The transformation from scarce to abundant data has contributed to a variety of functional changes that have both enhanced service quality and improved efficiency. This report examines factors related to the development of Tri-Met’s BDS that have contributed to its success in data archiving and analysis. The organization of the report includes a description of the BDS, a review of the types of analyses that have been supported by archived data, a discussion of factors that influenced decisions made on the design of the system, reflections on unrealized expectations and missed opportunities, and concluding observations. Title: Tri-Met's Experience With Automatic Passenger Counter and Automatic Vehicle Location Systems Author: Strathman, James G. Year: 2002 The Tri-County Metropolitan Transportation District of Oregon (Tri-Met) is one of about 30 metropolitan transit agencies that have deployed both automatic vehicle location (AVL) and automatic passenger counter (APC) systems (Casey, 1999). These technologies are important components of the agency’s new automated bus dispatching system (BDS). The AVL and APC systems at Tri-Met recover comprehensive operations and passenger activity data at the bus stop level that is archived for later analysis. The agency has gained a reputation as an industry leader in the areas of data archiving and the application of archived data to performance monitoring and analysis. Prior to the implementation of AVL and APC technology, Tri-Met, like others in the transit industry, relied on costly manual data recovery. During lean budget years in the early 1980s, the agency began using stand-alone APCs instead of ride checkers, and recovered very little operating data beyond what was required for Federal Transit Administration reporting. With its AVL and APC systems, Tri-Met is now automatically collecting and archiving over 500,000 stop and event data records per day. Offline analysis of this data supports a wide array of agency activities. The transformation from scarce to abundant data has contributed to a variety of functional changes that have both enhanced service quality and improved efficiency. This report examines factors related to the development of Tri-Met’s BDS that have contributed to its success in data archiving and analysis. The organization of the report includes a description of the BDS, a review of the types of analyses that have been supported by archived data, a discussion of factors that influenced decisions made on the design of the system, reflections on unrealized expectations and missed opportunities, and concluding observations. Close