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• 1. [Article] Tracking Trucks to Improve Performance

  Freight transportation is an important part of Oregon’s economy, and the Oregon Department of Transportation, or ODOT, continually observes the highway system to make sure it is running as smoothly as ...

  Citation × Citation Citation Abstract Copy Title: Tracking Trucks to Improve Performance Author: Cetin, Mecit, Monsere, Christopher M. Year: 2013 Freight transportation is an important part of Oregon’s economy, and the Oregon Department of Transportation, or ODOT, continually observes the highway system to make sure it is running as smoothly as possible. By monitoring the progress of individual trucks, ODOT can obtain performance metrics such as travel time, travel delays, and origin-destination flows. This information can help identify slow passages or bottlenecks in the highway system. Typical ways of obtaining these metrics, however, may involve purchasing expensive equipment, and may also raise privacy concerns if each truck is required to carry a tracking unit. To avoid these difficulties, Portland State University researcher Chris Monsere explored a simpler way to get freight performance measures using a probabilistic approach. Title: Tracking Trucks to Improve Performance Author: Cetin, Mecit, Monsere, Christopher M. Year: 2013 Freight transportation is an important part of Oregon’s economy, and the Oregon Department of Transportation, or ODOT, continually observes the highway system to make sure it is running as smoothly as possible. By monitoring the progress of individual trucks, ODOT can obtain performance metrics such as travel time, travel delays, and origin-destination flows. This information can help identify slow passages or bottlenecks in the highway system. Typical ways of obtaining these metrics, however, may involve purchasing expensive equipment, and may also raise privacy concerns if each truck is required to carry a tracking unit. To avoid these difficulties, Portland State University researcher Chris Monsere explored a simpler way to get freight performance measures using a probabilistic approach. Close

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

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

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

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

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

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

• 4. [Article] 2007 Portland Metropolitan Region Transportation System Performance Report

  Our transportation system is a key ingredient in the economy, quality of life and urban fabric of the Portland metropolitan area. It has been stated in the past that it is not possible to manage our transportation ...

  Citation × Citation Citation Abstract Copy Title: 2007 Portland Metropolitan Region Transportation System Performance Report Author: Bertini, Robert Year: 2008 Our transportation system is a key ingredient in the economy, quality of life and urban fabric of the Portland metropolitan area. It has been stated in the past that it is not possible to manage our transportation system tomorrow unless we understand how it is performing today. In this spirit, the Portland State University Center for Transportation Studies has been working with regional and statewide partners to develop new capabilities to measure, monitor and track the performance of the transportation system in real time and using archived data sources. We believe that it is possible to leverage these disparate data sources toward providing better transportation system performance information for planners, engineers, citizens, researchers and decision-makers. Using this information, we can collaboratively develop policies and programs that can help make our transportation system more efficient, equitable and effective. With this in mind, we are pleased to present the 2007 Portland Metropolitan Region Transportation System Performance Report. We have attempted to make this report comprehensive and multimodal in spirit. We truly view this as a starting point, a work in progress, and we intend to continue to improve the content and format of this report in years to come. Of the new charts that were added for this years’ report, several relate to environmental health or sustainability (air quality, drive-alone commuters, etc.). We are also in the process of developing other “green” performance measures such as motor vehicle emissions, fuel consumption, and person-miles traveled. These new performance measures will appear in future versions of this report. The Center for Transportation Studies strives to stimulate and conduct multidisciplinary research on transportation issues, facilitating the dissemination of information and encouraging the implementation of research results. We welcome both comments on this report and participation in Center for Transportation Studies programs and activities from all interested parties. We invite you to visit our website at www.cts.pdx.edu, and thank you in advance for your interest and input Title: 2007 Portland Metropolitan Region Transportation System Performance Report Author: Bertini, Robert Year: 2008 Our transportation system is a key ingredient in the economy, quality of life and urban fabric of the Portland metropolitan area. It has been stated in the past that it is not possible to manage our transportation system tomorrow unless we understand how it is performing today. In this spirit, the Portland State University Center for Transportation Studies has been working with regional and statewide partners to develop new capabilities to measure, monitor and track the performance of the transportation system in real time and using archived data sources. We believe that it is possible to leverage these disparate data sources toward providing better transportation system performance information for planners, engineers, citizens, researchers and decision-makers. Using this information, we can collaboratively develop policies and programs that can help make our transportation system more efficient, equitable and effective. With this in mind, we are pleased to present the 2007 Portland Metropolitan Region Transportation System Performance Report. We have attempted to make this report comprehensive and multimodal in spirit. We truly view this as a starting point, a work in progress, and we intend to continue to improve the content and format of this report in years to come. Of the new charts that were added for this years’ report, several relate to environmental health or sustainability (air quality, drive-alone commuters, etc.). We are also in the process of developing other “green” performance measures such as motor vehicle emissions, fuel consumption, and person-miles traveled. These new performance measures will appear in future versions of this report. The Center for Transportation Studies strives to stimulate and conduct multidisciplinary research on transportation issues, facilitating the dissemination of information and encouraging the implementation of research results. We welcome both comments on this report and participation in Center for Transportation Studies programs and activities from all interested parties. We invite you to visit our website at www.cts.pdx.edu, and thank you in advance for your interest and input Close