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OTREC-RR-430 By Christopher Monsere
Paperback: $4.49
Prints in 3-5 business days
This research report describes our efforts to assemble and develop a multimodal archive for the Portland-Vancouver region. The preliminary nature of the archiving process means that some of the data... More > are incomplete and samples. The arterial data sources available in the Portland-Vancouver region include data for local agencies (City of Portland, Clark County, WA, TriMet and C-TRAN) covering vehicle, transit, pedestrian, and bicycle modes. We provide descriptions of each data source and a spatial and temporal classification. The report describes the process for extracting data from the agency systems and transferring these data to our multimodal database. A number of novel visualizations were created. These are summarized in this report and examples are shown. Efforts to 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.< Less
OTREC-RR-430 By Christopher Monsere
eBook (PDF): $0.00
This research report describes our efforts to assemble and develop a multimodal archive for the Portland-Vancouver region. The preliminary nature of the archiving process means that some of the data... More > are incomplete and samples. The arterial data sources available in the Portland-Vancouver region include data for local agencies (City of Portland, Clark County, WA, TriMet and C-TRAN) covering vehicle, transit, pedestrian, and bicycle modes. We provide descriptions of each data source and a spatial and temporal classification. The report describes the process for extracting data from the agency systems and transferring these data to our multimodal database. A number of novel visualizations were created. These are summarized in this report and examples are shown. Efforts to 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.< Less
OTREC-RR-10-13 By Christopher Monsere
eBook (PDF): $0.00
Traffic oscillations are typical features of congested traffic flow that are characterized by recurring decelerations followed by accelerations (stop-and-go driving). This report describes the... More > impact of freeway traffic oscillations on traffic safety. This study employs a matched case-control design using high resolution traffic and crash data from a freeway segment. Traffic conditions prior to each crash were taken as cases, while traffic conditions during the same periods on days without crashes were taken as controls. These were also matched by presence of congestion, geometry and weather; 82 cases were extracted from data from 2004 to 2007. Conditional logistic regression models were developed based on the case-control samples. The results reveal that the standard deviation of speed (thus, oscillations) is a significant variable. The average traffic states prior to crashes were less significant than the speed variations in congestion.< Less
OTREC-RR-10-13 By Christopher Monsere
Paperback: $6.80
Prints in 3-5 business days
Traffic oscillations are typical features of congested traffic flow that are characterized by recurring decelerations followed by accelerations (stop-and-go driving). This report describes the... More > impact of freeway traffic oscillations on traffic safety. This study employs a matched case-control design using high resolution traffic and crash data from a freeway segment. Traffic conditions prior to each crash were taken as cases, while traffic conditions during the same periods on days without crashes were taken as controls. These were also matched by presence of congestion, geometry and weather; 82 cases were extracted from data from 2004 to 2007. Conditional logistic regression models were developed based on the case-control samples. The results reveal that the standard deviation of speed (thus, oscillations) is a significant variable. The average traffic states prior to crashes were less significant than the speed variations in congestion.< Less
OTREC-RR-12-04 By Christopher Monsere & Mecit Cetin
eBook (PDF): $0.00
Vehicle re-identification matches vehicles crossing two different locations. Building on a previous study, we investigate different methods for re-identification and explore factors that impact... More > accuracy. Archived data from weigh-in-motion (WIM) stations in Oregon are used to develop, calibrate, and test vehicle re-identification algorithms. In addition to the Bayesian approach developed in the previous study, a neural network model is developed. The results show both methods to be effective while the Bayesian method results are more accurate. A comprehensive analysis employing the Bayesian algorithm matches vehicles that cross upstream and downstream pairs of WIM sites. Data from 14 different pairs of WIM sites are used to evaluate how factors such as distance, travel time variability, truck volumes, and sensors impact accuracy. The testing showed a large variation in accuracy, with sensor accuracy and volumes have the greatest impacts, while distance alone shows no significant impact.< Less
OTREC-RR-12-04 By Christopher Monsere & Mecit Cetin
Paperback: $6.70
Prints in 3-5 business days
Vehicle re-identification matches vehicles crossing two different locations. Building on a previous study, we investigate different methods for re-identification and explore factors that impact... More > accuracy. Archived data from weigh-in-motion (WIM) stations in Oregon are used to develop, calibrate, and test vehicle re-identification algorithms. In addition to the Bayesian approach developed in the previous study, a neural network model is developed. The results show both methods to be effective while the Bayesian method results are more accurate. A comprehensive analysis employing the Bayesian algorithm matches vehicles that cross upstream and downstream pairs of WIM sites. Data from 14 different pairs of WIM sites are used to evaluate how factors such as distance, travel time variability, truck volumes, and sensors impact accuracy. The testing showed a large variation in accuracy, with sensor accuracy and volumes have the greatest impacts, while distance alone shows no significant impact.< Less
OTREC-RR-12-02 By Karen Dixon et al.
eBook (PDF): $0.00
The Highway Safety Manual (HSM) published by the American Association of State Highway and Transportation Officials in the spring of 2010 includes safety predictive methods which are used to estimate... More > the safety of a transportation facility. However, the safety performance functions (SPFs) were developed for states other than Oregon. Because of differences in crash reporting, driver and animal populations, and weather conditions, officials need calibrated SPFs for Oregon facilities. Predictive methods were developed for rural two-lane roads, rural multilane roads, and urban/suburban arterial roads. In this project SPFs were calibrated for these facility types based on their historic performance in Oregon. The report illustrates methods of site selection, collection of crash and site data, analysis methods, and an evaluation of crash severity distribution methods. Oregon agencies can use calibrated HSM predictive methods to more accurately assess expected facility safety performance for Oregon conditions.< Less
OTREC-RR-11-28 By Christopher Monsere et al.
eBook (PDF): $0.00
This report describes the early development of the Oregon Traffic Safety Data Archive (OrTSDA) with its mission to “build the knowledge base of traffic safety data in Oregon”. The archive... More > aims to provide current and historical sets of related data with an online interface, and encompass complete documentation. OrTSDA contains statewide reported motor vehicle crashes, population data, estimated vehicle miles traveled, traffic crime, and data on driving under the influence measures, which are available online for query and analysis. The archive produces safety performance metrics for statewide, county and city aggregations. Pre-built queries can filter for crash type, month, time, and severity. Raw crash data is available for experienced users. A map-based tool allows selection of crash data within a drawn boundary. This report includes a review of other online highway safety data portals, noting that interactive crash portals are restricted to a few state agencies or research university partners.< Less
OTREC-RR-11-28 By Christopher Monsere et al.
Paperback: $6.65
Prints in 3-5 business days
This report describes the early development of the Oregon Traffic Safety Data Archive (OrTSDA) with its mission to “build the knowledge base of traffic safety data in Oregon”. The archive... More > aims to provide current and historical sets of related data with an online interface, and encompass complete documentation. OrTSDA contains statewide reported motor vehicle crashes, population data, estimated vehicle miles traveled, traffic crime, and data on driving under the influence measures, which are available online for query and analysis. The archive produces safety performance metrics for statewide, county and city aggregations. Pre-built queries can filter for crash type, month, time, and severity. Raw crash data is available for experienced users. A map-based tool allows selection of crash data within a drawn boundary. This report includes a review of other online highway safety data portals, noting that interactive crash portals are restricted to a few state agencies or research university partners.< Less
OTREC-RR-11-07 By Christopher Monsere et al.
eBook (PDF): $0.00
This project evaluates the feasibility of re-identifying commercial trucks with data automatically collected at Oregon weigh-in-motion (WIM) stations. The methods consist of two main stages. The... More > first uses a Bayesian model to match each vehicle from the downstream station to the most “similar” upstream vehicle. In the second stage, methods are introduced to screen out vehicles crossing only downstream and to adjust accuracy vs. total number of vehicles matched by calculating the highest and second highest similarity measures for each vehicle. The proposed approach improves the accuracy of re-identification significantly. The models are applied to data from three WIM stations, creating two different “links” of 125 and 145 miles respectively. The algorithms match around 95% of trucks crossing both sites with about 90% accuracy. A threshold parameter allows adjustment of accuracy vs. total matched vehicles. When travel times vary widely between sites the mismatch rate increases.< Less

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Our World Our World By Deleah Payne
Paperback: $21.60