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• 1. [Article] Contextual Influences on Trip Generation

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

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

• 2. [Article] The Effects of Commuter Rail on Population Deconcentration and Commuting: A Salt Lake City Case Study

  All transportation systems have the ability to transform human settlement patterns, which can affect a range of social, economic and environmental issues. Considering investments in rail infrastructure ...

  Citation × Citation Citation Abstract Copy Title: The Effects of Commuter Rail on Population Deconcentration and Commuting: A Salt Lake City Case Study Author: Ganning, Joanna, Beaudoin, Mercedes, Brewer, Simon, Kim, Keuntae, Park, Keunhyun Year: 2016 All transportation systems have the ability to transform human settlement patterns, which can affect a range of social, economic and environmental issues. Considering investments in rail infrastructure have increased in recent decades (Bureau of Transportation Statistics, 2007; Israel & Cohen-Blankshtain, 2010), it is important for planners and researchers to understand how these rail systems influence land use, metropolitan development patterns, and population migration. The following paragraphs summarize the studies and their findings. The Effects of Commuter Rail Establishment on the Relationships between the Built Environment, Travel Behavior, and Residential Self- Selection (RSS): To help regional and transportation planners better understand the role that commuter rail plays in directing intra-regional development, this chapter provides a longitudinal investigation of the influence of commuter rail on surrounding neighborhoods’ RSS, travel behavior and the built environment. We first analyze the role of commuter rail establishment in influencing change in neighborhood-level demographics, housing and economics (signs of RSS), and travel behavior. Second, we compare surveyed commuter rail riders to residents of the commuter rail stations’ host and neighboring areas. The results indicate that the development of commuter rail does not alter the host tracts in any of the characteristics observed, but rather suppresses population growth in neighboring tracts. Paired with direct evidence from a commuter rail user survey, we conclude that the use of commuter rail is more likely influenced by the built environment than by RSS. The Effects of Commuter Rail Establishment on Population Deconcentration: Research to date has not established the efficacy of commuter rail systems in attracting migrants most likely to use such an amenity. Through the application of a modified population deconcentration model, this chapter finds that the provision of a commuter rail station significantly increases neighborhood-level out-commuting and gross migration, which signals success in attracting migrants requiring commuting infrastructure. These findings also signal that commuter rail encourages regional population deconcentration, but the evidence is insufficient to form a conclusion and the evidence from Chapters 2 and 4 signal otherwise. Developing an Agent-Based Model (ABM) For Estimation of Land Use Changes around Commuter Rail Stations over Time: This chapter improves the understanding of commuter rails’ effect on future land use changes through spatial interaction modeling. In particular, we develop an innovative agent-based model (ABM) that allows us to estimate and visualize the probability of land use changes per parcel based on proximity to commuter rail stations, freeway exits, and the region’s central business district. Briefly, this chapter concludes that the development of a commuter rail station is statistically significantly associated with decreases in single-family residential land use near the station, which is met by increases in multifamily and mixed-use development. The spatial effects of stations on individual land uses vary by land use type, and no generalizable area of influence could be established. This report points to potential future research, as well as implications for planning practitioners. Title: The Effects of Commuter Rail on Population Deconcentration and Commuting: A Salt Lake City Case Study Author: Ganning, Joanna, Beaudoin, Mercedes, Brewer, Simon, Kim, Keuntae, Park, Keunhyun Year: 2016 All transportation systems have the ability to transform human settlement patterns, which can affect a range of social, economic and environmental issues. Considering investments in rail infrastructure have increased in recent decades (Bureau of Transportation Statistics, 2007; Israel & Cohen-Blankshtain, 2010), it is important for planners and researchers to understand how these rail systems influence land use, metropolitan development patterns, and population migration. The following paragraphs summarize the studies and their findings. The Effects of Commuter Rail Establishment on the Relationships between the Built Environment, Travel Behavior, and Residential Self- Selection (RSS): To help regional and transportation planners better understand the role that commuter rail plays in directing intra-regional development, this chapter provides a longitudinal investigation of the influence of commuter rail on surrounding neighborhoods’ RSS, travel behavior and the built environment. We first analyze the role of commuter rail establishment in influencing change in neighborhood-level demographics, housing and economics (signs of RSS), and travel behavior. Second, we compare surveyed commuter rail riders to residents of the commuter rail stations’ host and neighboring areas. The results indicate that the development of commuter rail does not alter the host tracts in any of the characteristics observed, but rather suppresses population growth in neighboring tracts. Paired with direct evidence from a commuter rail user survey, we conclude that the use of commuter rail is more likely influenced by the built environment than by RSS. The Effects of Commuter Rail Establishment on Population Deconcentration: Research to date has not established the efficacy of commuter rail systems in attracting migrants most likely to use such an amenity. Through the application of a modified population deconcentration model, this chapter finds that the provision of a commuter rail station significantly increases neighborhood-level out-commuting and gross migration, which signals success in attracting migrants requiring commuting infrastructure. These findings also signal that commuter rail encourages regional population deconcentration, but the evidence is insufficient to form a conclusion and the evidence from Chapters 2 and 4 signal otherwise. Developing an Agent-Based Model (ABM) For Estimation of Land Use Changes around Commuter Rail Stations over Time: This chapter improves the understanding of commuter rails’ effect on future land use changes through spatial interaction modeling. In particular, we develop an innovative agent-based model (ABM) that allows us to estimate and visualize the probability of land use changes per parcel based on proximity to commuter rail stations, freeway exits, and the region’s central business district. Briefly, this chapter concludes that the development of a commuter rail station is statistically significantly associated with decreases in single-family residential land use near the station, which is met by increases in multifamily and mixed-use development. The spatial effects of stations on individual land uses vary by land use type, and no generalizable area of influence could be established. This report points to potential future research, as well as implications for planning practitioners. Close

• 3. [Article] Improved Safety Performance Functions for Signalized Intersections

  For this effort, the research team developed new safety performance functions (SPFs) for signalized intersections in Oregon. The modeling dataset consisted of 964 crashes from a total of 73 intersections ...

  Citation × Citation Citation Abstract Copy Title: Improved Safety Performance Functions for Signalized Intersections Author: Dixon, Karen, Monsere, Christopher, Avelar, Raul, Barnett, Joel Stephen, Escobar, Paty, Kothuri, Sirisha Murthy Year: 2015 For this effort, the research team developed new safety performance functions (SPFs) for signalized intersections in Oregon. The modeling dataset consisted of 964 crashes from a total of 73 intersections that were randomly selected based on the presence of a traffic signal (identified through the crash data records). The SPFs were developed using a Poissonlognormal Generalized Linear Mixed model framework for total crashes and severe injury crashes (coded as KAB). Three SPFs were developed: 1) an SPF for total crashes, which relies on both major and minor AADTs to predict the expected number of crashes; 2) an SPF for KAB crashes, whose predictions derive from both AADTs as well as from the speed limit on the major road; and (3) a severity model to predict the proportion of KAB crashes to be used in combination with the SPF for total crashes. The research analyses determined that the speed limit variable significantly improved the quality of the SPFs and severity model, and as expected, suggests increasing severity with speed differentials. The models were validated spatially and temporally based on additional sites and using an additional year of data. The models all performed well during the validation; however enhanced models to improve model reliability were developed based on the larger dataset. As part of the model development, this research also explored a variety of rules to identify crashes as intersection-related based on the crash geo-location (including the common 250 feet rule). Crashes were manually classified from the combined data available from the geo-location of crashes, the geometric database, and the various fields in the Oregon crash database. These classifications were then compared to a number of rule options for classifying them as intersection crashes. The analysis revealed that the best performing rule is to use crashes that were geo-located within 300 feet of the centerline intersection at signalized locations plus crashes where the crash report indicates that they were associated with a traffic control device (i.e. traffic signal). Finally, this research effort developed models to estimate to estimate minor road AADT for use in safety analysis where this exposure information is not available. These models were developed from data from 66 intersections with known minor and major AADT volumes and validated with data from another 25 intersections. Significant model variables included major AADT, number of approach lanes, functional class, presence of a two-way leftturn lane, and parallel road AADT. Title: Improved Safety Performance Functions for Signalized Intersections Author: Dixon, Karen, Monsere, Christopher, Avelar, Raul, Barnett, Joel Stephen, Escobar, Paty, Kothuri, Sirisha Murthy Year: 2015 For this effort, the research team developed new safety performance functions (SPFs) for signalized intersections in Oregon. The modeling dataset consisted of 964 crashes from a total of 73 intersections that were randomly selected based on the presence of a traffic signal (identified through the crash data records). The SPFs were developed using a Poissonlognormal Generalized Linear Mixed model framework for total crashes and severe injury crashes (coded as KAB). Three SPFs were developed: 1) an SPF for total crashes, which relies on both major and minor AADTs to predict the expected number of crashes; 2) an SPF for KAB crashes, whose predictions derive from both AADTs as well as from the speed limit on the major road; and (3) a severity model to predict the proportion of KAB crashes to be used in combination with the SPF for total crashes. The research analyses determined that the speed limit variable significantly improved the quality of the SPFs and severity model, and as expected, suggests increasing severity with speed differentials. The models were validated spatially and temporally based on additional sites and using an additional year of data. The models all performed well during the validation; however enhanced models to improve model reliability were developed based on the larger dataset. As part of the model development, this research also explored a variety of rules to identify crashes as intersection-related based on the crash geo-location (including the common 250 feet rule). Crashes were manually classified from the combined data available from the geo-location of crashes, the geometric database, and the various fields in the Oregon crash database. These classifications were then compared to a number of rule options for classifying them as intersection crashes. The analysis revealed that the best performing rule is to use crashes that were geo-located within 300 feet of the centerline intersection at signalized locations plus crashes where the crash report indicates that they were associated with a traffic control device (i.e. traffic signal). Finally, this research effort developed models to estimate to estimate minor road AADT for use in safety analysis where this exposure information is not available. These models were developed from data from 66 intersections with known minor and major AADT volumes and validated with data from another 25 intersections. Significant model variables included major AADT, number of approach lanes, functional class, presence of a two-way leftturn lane, and parallel road AADT. Close

• 4. [Article] Sustainable Drainage Systems: Helping People Live with Water

  Sustainable drainage systems or ‘Suds’ are increasingly accepted as an effective means of ‘making space for water’, adapting to possible climate change and helping communities become more flood and drought ...

  Citation × Citation Citation Abstract Copy Title: Sustainable Drainage Systems: Helping People Live with Water Author: Everett, Glyn, Lamond, Jessica, Morzillo, Anita T., Chan, Faith Ka Shun, Matsler, Annie Marissa Year: 2016 Sustainable drainage systems or ‘Suds’ are increasingly accepted as an effective means of ‘making space for water’, adapting to possible climate change and helping communities become more flood and drought resilient. This study explores potential shifts in perception and attitude through Suds installation, development and habituation. Attitudes and awareness in communities in the USA and UK, where Suds have been in place for some time, were compared and contrasted, examining any evolution of beliefs and practices and wider community resilience. The principal finding was that there existed a lack of understanding about the existence and function of Suds. The paper concludes that consultation regarding solutions during Suds planning and installation, and ongoing dialogue afterwards, could usefully be explored as a means to improve local awareness of and satisfaction with Suds and promote greater understanding of their function. This may in turn encourage behaviour change to improve longer-term functionality... Title: Sustainable Drainage Systems: Helping People Live with Water Author: Everett, Glyn, Lamond, Jessica, Morzillo, Anita T., Chan, Faith Ka Shun, Matsler, Annie Marissa Year: 2016 Sustainable drainage systems or ‘Suds’ are increasingly accepted as an effective means of ‘making space for water’, adapting to possible climate change and helping communities become more flood and drought resilient. This study explores potential shifts in perception and attitude through Suds installation, development and habituation. Attitudes and awareness in communities in the USA and UK, where Suds have been in place for some time, were compared and contrasted, examining any evolution of beliefs and practices and wider community resilience. The principal finding was that there existed a lack of understanding about the existence and function of Suds. The paper concludes that consultation regarding solutions during Suds planning and installation, and ongoing dialogue afterwards, could usefully be explored as a means to improve local awareness of and satisfaction with Suds and promote greater understanding of their function. This may in turn encourage behaviour change to improve longer-term functionality... Close

• 5. [Article] Modeling Impact of Technological Changes on Urban Commercial Trips by Commercial Activity Routing Type

  Several noteworthy developments in logistics practice have taken place without an equivalent and comprehensive development in urban freight transportation modeling. Part of the problem is the lack of deep ...

  Citation × Citation Citation Abstract Copy Title: Modeling Impact of Technological Changes on Urban Commercial Trips by Commercial Activity Routing Type Author: Figliozzi, Miguel Year: 2006 Several noteworthy developments in logistics practice have taken place without an equivalent and comprehensive development in urban freight transportation modeling. Part of the problem is the lack of deep understanding of the workings of distribution processes in relation to the generation of truck traffic. This study emphasizes the role and importance that distribution network size and information and communications technology have on the truck traffic flows that materialize as the supply chain flows over the public infrastructure. A concept is developed of commercial activity routing types that characterize the interplay between transportation demand requests and routing characteristics. This research contributes to the field by proposing a novel and detailed characterization of truck flows in a supply chain context. With well-known, yet simple, models and formulas from vehicle routing, operations research, and management science literature, behavioral insights are derived about distributors' and carriers' routing and order-sizing decisions, since routing constraints and second-order effects are important drivers of truck flows. The main contribution is to bring a new commercial activity-routing perspective and a deeper level of operational decision-making analysis to cope with the intricacies of freight transportation modeling. Title: Modeling Impact of Technological Changes on Urban Commercial Trips by Commercial Activity Routing Type Author: Figliozzi, Miguel Year: 2006 Several noteworthy developments in logistics practice have taken place without an equivalent and comprehensive development in urban freight transportation modeling. Part of the problem is the lack of deep understanding of the workings of distribution processes in relation to the generation of truck traffic. This study emphasizes the role and importance that distribution network size and information and communications technology have on the truck traffic flows that materialize as the supply chain flows over the public infrastructure. A concept is developed of commercial activity routing types that characterize the interplay between transportation demand requests and routing characteristics. This research contributes to the field by proposing a novel and detailed characterization of truck flows in a supply chain context. With well-known, yet simple, models and formulas from vehicle routing, operations research, and management science literature, behavioral insights are derived about distributors' and carriers' routing and order-sizing decisions, since routing constraints and second-order effects are important drivers of truck flows. The main contribution is to bring a new commercial activity-routing perspective and a deeper level of operational decision-making analysis to cope with the intricacies of freight transportation modeling. Close

• 6. [Article] Pend Oreille River, Box Canyon Model: Model Development and Calibration

  The purpose of this study was to improve the existing Version 3.0 application of CE-QUAL-W2 of the Pend Oreille River between Box Canyon Dam and Albeni Falls Dam by performing the tasks outlined above. ...

  Citation × Citation Citation Abstract Copy Title: Pend Oreille River, Box Canyon Model: Model Development and Calibration Author: Annear, Robert Leslie, Berger, Chris, Wells, Scott A. Year: 2006 The purpose of this study was to improve the existing Version 3.0 application of CE-QUAL-W2 of the Pend Oreille River between Box Canyon Dam and Albeni Falls Dam by performing the tasks outlined above. In addition, the use of field data from 2004 as an additional calibration year would improve the confidence in the model’s predictive ability for temperature. The model simulations were run from January 1st to December 31st in each of the 3 years of model simulation: 1997, 1998 and 2004. The model chosen for development is CE-QUAL-W2 Version 3.5 (Cole and Wells, 2006). This is a twodimensional unsteady hydrodynamic and water quality model that includes typical eutrophication parameters (algae, nutrients, temperature, organic matter, dissolved oxygen, pH). The PSU-WQRG is a center for development of this modeling tool (see http://www.cee.pdx.edu/w2). Title: Pend Oreille River, Box Canyon Model: Model Development and Calibration Author: Annear, Robert Leslie, Berger, Chris, Wells, Scott A. Year: 2006 The purpose of this study was to improve the existing Version 3.0 application of CE-QUAL-W2 of the Pend Oreille River between Box Canyon Dam and Albeni Falls Dam by performing the tasks outlined above. In addition, the use of field data from 2004 as an additional calibration year would improve the confidence in the model’s predictive ability for temperature. The model simulations were run from January 1st to December 31st in each of the 3 years of model simulation: 1997, 1998 and 2004. The model chosen for development is CE-QUAL-W2 Version 3.5 (Cole and Wells, 2006). This is a twodimensional unsteady hydrodynamic and water quality model that includes typical eutrophication parameters (algae, nutrients, temperature, organic matter, dissolved oxygen, pH). The PSU-WQRG is a center for development of this modeling tool (see http://www.cee.pdx.edu/w2). Close

• 7. [Article] 3D Hydrodynamic Model Development and Verification

  A three-dimensional numerical model was developed to simulate hydrodynamic, temperature, and water quality distributions in rivers and lakes. In an attempt to get rid of the extra approximation and complexity, ...

  Citation × Citation Citation Abstract Copy Title: 3D Hydrodynamic Model Development and Verification Author: Al-Zubaidi, Hussein A. M. Year: 2016 A three-dimensional numerical model was developed to simulate hydrodynamic, temperature, and water quality distributions in rivers and lakes. In an attempt to get rid of the extra approximation and complexity, no coordinate transformation has been done and z-coordinate system has been employed. The governing equations are the continuity equation, free surface equation, momentum equations, and conservation equations of temperature and water quality. The model employs the time splitting technique which allows splitting the directions in which we end with two-dimensional governing equations and eventually the solution ends with a tri-diagonal matrix, which is easily solved by Thomas algorithm. The first step after developing a numerical model and before adding more features or applying the model to a real case, the model should be verified. The verification of the model was done by implementing the model to known solutions test cases in additional to evaluating whether the code preserves fluid mass. A series of test cases is performed by comparing the model results with the analytical solutions as proposed by many modelers. The model showed good agreement between the analytical and the numerical solution. Title: 3D Hydrodynamic Model Development and Verification Author: Al-Zubaidi, Hussein A. M. Year: 2016 A three-dimensional numerical model was developed to simulate hydrodynamic, temperature, and water quality distributions in rivers and lakes. In an attempt to get rid of the extra approximation and complexity, no coordinate transformation has been done and z-coordinate system has been employed. The governing equations are the continuity equation, free surface equation, momentum equations, and conservation equations of temperature and water quality. The model employs the time splitting technique which allows splitting the directions in which we end with two-dimensional governing equations and eventually the solution ends with a tri-diagonal matrix, which is easily solved by Thomas algorithm. The first step after developing a numerical model and before adding more features or applying the model to a real case, the model should be verified. The verification of the model was done by implementing the model to known solutions test cases in additional to evaluating whether the code preserves fluid mass. A series of test cases is performed by comparing the model results with the analytical solutions as proposed by many modelers. The model showed good agreement between the analytical and the numerical solution. Close

• 8. [Article] Exploratory Methods for Truck Re-Identification in a Statewide Network Based on Axle Weight and Axle Spacing Data to Enhance Freight Metrics: Phase II

  Vehicle re-identification methods can be used to anonymously match vehicles crossing two different locations based on vehicle attribute data. This research builds upon a previous study and investigates ...

  Citation × Citation Citation Abstract Copy Title: Exploratory Methods for Truck Re-Identification in a Statewide Network Based on Axle Weight and Axle Spacing Data to Enhance Freight Metrics: Phase II Author: Cetin, Mecit, Monsere, Christopher M. Year: 2012 Vehicle re-identification methods can be used to anonymously match vehicles crossing two different locations based on vehicle attribute data. This research builds upon a previous study and investigates different methods for solving the re-identification problem and explores some of the factors that impact the accuracy of the results. To support this work, archived data from weigh-in-motion (WIM) stations in Oregon are used for developing, calibrating, and testing vehicle re-identification algorithms. In addition to the Bayesian approach developed by the researchers in the previous study, a neural network model is developed for solving the re-identification problem. The results from the testing datasets showed that both methods can be effective in solving the re-identification problem while the Bayesian method yields more accurate results. A comprehensive analysis is performed to investigate the key factors impacting the accuracy of the results. The analyses are performed by employing the Bayesian algorithm to match commercial vehicles that cross upstream and downstream pairs of WIM sites that are separated by long distances ranging from 70 to 214 miles. Data from 14 different pairs of WIM sites are used to evaluate how matching accuracy is impacted by various factors such as the distance between two sites, travel time variability, truck volumes, and sensor accuracy or consistency of measurements. After running the vehicle re-identification algorithm for each one of these 14 pairs of sites, the matching error rates are reported. The results from the testing datasets showed a large variation in terms of accuracy. It is found that sensor accuracy and volumes have the greatest impacts on matching accuracy whereas the distance alone does not have a significant impact. Overall, for estimating travel times and origin-destination flows between two WIM sites, the methods developed in this project can be used to effectively match commercial vehicles crossing two data collection sites that are separated by long distances. Title: Exploratory Methods for Truck Re-Identification in a Statewide Network Based on Axle Weight and Axle Spacing Data to Enhance Freight Metrics: Phase II Author: Cetin, Mecit, Monsere, Christopher M. Year: 2012 Vehicle re-identification methods can be used to anonymously match vehicles crossing two different locations based on vehicle attribute data. This research builds upon a previous study and investigates different methods for solving the re-identification problem and explores some of the factors that impact the accuracy of the results. To support this work, archived data from weigh-in-motion (WIM) stations in Oregon are used for developing, calibrating, and testing vehicle re-identification algorithms. In addition to the Bayesian approach developed by the researchers in the previous study, a neural network model is developed for solving the re-identification problem. The results from the testing datasets showed that both methods can be effective in solving the re-identification problem while the Bayesian method yields more accurate results. A comprehensive analysis is performed to investigate the key factors impacting the accuracy of the results. The analyses are performed by employing the Bayesian algorithm to match commercial vehicles that cross upstream and downstream pairs of WIM sites that are separated by long distances ranging from 70 to 214 miles. Data from 14 different pairs of WIM sites are used to evaluate how matching accuracy is impacted by various factors such as the distance between two sites, travel time variability, truck volumes, and sensor accuracy or consistency of measurements. After running the vehicle re-identification algorithm for each one of these 14 pairs of sites, the matching error rates are reported. The results from the testing datasets showed a large variation in terms of accuracy. It is found that sensor accuracy and volumes have the greatest impacts on matching accuracy whereas the distance alone does not have a significant impact. Overall, for estimating travel times and origin-destination flows between two WIM sites, the methods developed in this project can be used to effectively match commercial vehicles crossing two data collection sites that are separated by long distances. Close

• 9. [Article] Bayesian Models for Reidentification of Trucks Over Long Distances on the Basis of Axle Measurement Data

  Vehicle reidentification methods can be used to anonymously match vehicles crossing 2 different locations on the basis of vehicle attribute data. In this article, reidentification methods are developed ...

  Citation × Citation Citation Abstract Copy Title: Bayesian Models for Reidentification of Trucks Over Long Distances on the Basis of Axle Measurement Data Author: Cetin, Mecit, Monsere, Christopher, Nichols, Andrew Year: 2011 Vehicle reidentification methods can be used to anonymously match vehicles crossing 2 different locations on the basis of vehicle attribute data. In this article, reidentification methods are developed to match commercial vehicles that cross 2 weigh-in-motion sites in Oregon that are separated by 145 miles. Using vehicle length and axle data as attributes to characterize vehicles, a Bayesian model is developed that uses probability density functions obtained by fitting Gaussian mixture models to a sample data set of matched vehicles. The reidentification model when applied to a test data set (where each downstream vehicle also crosses the upstream site) matches vehicles with an accuracy of 91% when both axle weight and axle spacings data are used. To account for the fact that not all vehicles in the downstream also cross the upstream site, an additional new step is developed to screen mismatched vehicles produced by the algorithm. For this step, several screening methods are developed that allow the user to trade off the total number of matched vehicles and error rate. For evaluating the effectiveness of the screening methods, 2 scenarios are considered. In the first scenario, only common vehicles that cross both the upstream and downstream sites are considered, whereas in the second scenario all downstream vehicles are considered. It is shown that the mismatch error can be reduced to as low as 1% and 5% at the expense of not matching about 25% of the common vehicles (crossing both sites) for the first and second scenarios, respectively. Title: Bayesian Models for Reidentification of Trucks Over Long Distances on the Basis of Axle Measurement Data Author: Cetin, Mecit, Monsere, Christopher, Nichols, Andrew Year: 2011 Vehicle reidentification methods can be used to anonymously match vehicles crossing 2 different locations on the basis of vehicle attribute data. In this article, reidentification methods are developed to match commercial vehicles that cross 2 weigh-in-motion sites in Oregon that are separated by 145 miles. Using vehicle length and axle data as attributes to characterize vehicles, a Bayesian model is developed that uses probability density functions obtained by fitting Gaussian mixture models to a sample data set of matched vehicles. The reidentification model when applied to a test data set (where each downstream vehicle also crosses the upstream site) matches vehicles with an accuracy of 91% when both axle weight and axle spacings data are used. To account for the fact that not all vehicles in the downstream also cross the upstream site, an additional new step is developed to screen mismatched vehicles produced by the algorithm. For this step, several screening methods are developed that allow the user to trade off the total number of matched vehicles and error rate. For evaluating the effectiveness of the screening methods, 2 scenarios are considered. In the first scenario, only common vehicles that cross both the upstream and downstream sites are considered, whereas in the second scenario all downstream vehicles are considered. It is shown that the mismatch error can be reduced to as low as 1% and 5% at the expense of not matching about 25% of the common vehicles (crossing both sites) for the first and second scenarios, respectively. Close

• 10. [Article] A finite difference soil-structure interaction study of a section of the Bonneville Navigation Lock buttress diaphragm wall utilizing pressuremeter test results

  The P-y curve, used in current practice as an efficient Iine-load vs. soi displacement model for input into the finite difference method of laterally loaded pile analysis, is extended in this study for ...

  Citation × Citation Citation Abstract Copy Title: A finite difference soil-structure interaction study of a section of the Bonneville Navigation Lock buttress diaphragm wall utilizing pressuremeter test results Author: McCormack, Thomas C. Year: 1987 The P-y curve, used in current practice as an efficient Iine-load vs. soi displacement model for input into the finite difference method of laterally loaded pile analysis, is extended in this study for use with cohesionless soils in diaphragm wall analysis on the Personal Computer with the BMCOL7 program. An analogous W-y curve is proposed, an elastic-plastic model with line-load limits developed from classical earth-pressure theories. A new formula for predicting a horizontal walI modulus for cohesionless soiIs from the pressuremeter modulus is developed for use in predicting the displacements on the W-y curves. The resulting modulus values are shown to yield reasonable displacements values. A new procedure for modeling preloaded tie-back anchors and staged excavation for diaphragm walIs was developed, utiIizing multiple computer runs, updated the W-y curves, and superposition of deflections. These new developments were applied to a parametric study of a deflection-critical section of the new Bonnevilie Nav-Lock Buttress Diaphragm Wall, for which extensive high-quality pressuremeter test results were available. Deflection curves of the wall are presented, showing the effect of variations in anchor preload, walI cracking, anchor slip, at-rest pressure, and soiI modulus. The results indicate that preloading will reduce wall deflections by at least 4-fold, but that wall cracking can potentially double deflections. Safety factors against passive soil failure were determined to be about 5 at anchor preload, and more than 40 after fulI excavation. Title: A finite difference soil-structure interaction study of a section of the Bonneville Navigation Lock buttress diaphragm wall utilizing pressuremeter test results Author: McCormack, Thomas C. Year: 1987 The P-y curve, used in current practice as an efficient Iine-load vs. soi displacement model for input into the finite difference method of laterally loaded pile analysis, is extended in this study for use with cohesionless soils in diaphragm wall analysis on the Personal Computer with the BMCOL7 program. An analogous W-y curve is proposed, an elastic-plastic model with line-load limits developed from classical earth-pressure theories. A new formula for predicting a horizontal walI modulus for cohesionless soiIs from the pressuremeter modulus is developed for use in predicting the displacements on the W-y curves. The resulting modulus values are shown to yield reasonable displacements values. A new procedure for modeling preloaded tie-back anchors and staged excavation for diaphragm walIs was developed, utiIizing multiple computer runs, updated the W-y curves, and superposition of deflections. These new developments were applied to a parametric study of a deflection-critical section of the new Bonnevilie Nav-Lock Buttress Diaphragm Wall, for which extensive high-quality pressuremeter test results were available. Deflection curves of the wall are presented, showing the effect of variations in anchor preload, walI cracking, anchor slip, at-rest pressure, and soiI modulus. The results indicate that preloading will reduce wall deflections by at least 4-fold, but that wall cracking can potentially double deflections. Safety factors against passive soil failure were determined to be about 5 at anchor preload, and more than 40 after fulI excavation. Close