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• 1. [Article] Evaluation of Advanced Traffic Control Systems

  Researchers from Portland State University develop performance measures and algorithms for evaluation of state-of-the-art traffic signal control technologies..

  Citation × Citation Citation Abstract Copy Title: Evaluation of Advanced Traffic Control Systems Author: Figliozzi, Miguel Year: 2014 Researchers from Portland State University develop performance measures and algorithms for evaluation of state-of-the-art traffic signal control technologies.. Title: Evaluation of Advanced Traffic Control Systems Author: Figliozzi, Miguel Year: 2014 Researchers from Portland State University develop performance measures and algorithms for evaluation of state-of-the-art traffic signal control technologies.. Close

• 2. [Article] A Model for Better Crosswalk Safety

  NITC researchers from Portland State University developed models to find what factors affected vehicles’ compliance with pedestrian safety laws. The results suggest that treatments discouraging accelerating ...

  Citation × Citation Citation Abstract Copy Title: A Model for Better Crosswalk Safety Author: Figliozzi, Miguel Year: 2017 NITC researchers from Portland State University developed models to find what factors affected vehicles’ compliance with pedestrian safety laws. The results suggest that treatments discouraging accelerating toward a crosswalk could help increase pedestrian safety. Title: A Model for Better Crosswalk Safety Author: Figliozzi, Miguel Year: 2017 NITC researchers from Portland State University developed models to find what factors affected vehicles’ compliance with pedestrian safety laws. The results suggest that treatments discouraging accelerating toward a crosswalk could help increase pedestrian safety. Close

• 3. [Article] Understanding Delivery Routes in Urban Areas

  Supply chains and urban areas cannot thrive without the efficient movement of goods. A recent study indicates that commercial vehicles carrying goods or providing services account for, on average, almost ...

  Citation × Citation Citation Abstract Copy Title: Understanding Delivery Routes in Urban Areas Author: Figliozzi, Miguel Year: 2009 Supply chains and urban areas cannot thrive without the efficient movement of goods. A recent study indicates that commercial vehicles carrying goods or providing services account for, on average, almost 10 percent of the total vehicle miles traveled (VMT) in medium to large urban areas. A predominant share of these trips takes place within a multi-stop tour. In order to develop a well-organized system for moving freight through urban areas, it is crucial to understand and quantify how routes and distribution decisions affect commercial vehicle flows and VMTs. In the past, transportation planning models have focused on passenger movements but not on freight routes or on estimating commercial vehicle activities or VMT. This research provides new methods to quantify the effect of delivery size and time windows in urban areas. This project aimed to determine how best to obtain practical and intuitive approximations on the length of commercial vehicle tours and miles traveled in urban areas. Additionally, the project tested various means of estimating the impact of time windows and delivery sizes on commercial VMTs. Title: Understanding Delivery Routes in Urban Areas Author: Figliozzi, Miguel Year: 2009 Supply chains and urban areas cannot thrive without the efficient movement of goods. A recent study indicates that commercial vehicles carrying goods or providing services account for, on average, almost 10 percent of the total vehicle miles traveled (VMT) in medium to large urban areas. A predominant share of these trips takes place within a multi-stop tour. In order to develop a well-organized system for moving freight through urban areas, it is crucial to understand and quantify how routes and distribution decisions affect commercial vehicle flows and VMTs. In the past, transportation planning models have focused on passenger movements but not on freight routes or on estimating commercial vehicle activities or VMT. This research provides new methods to quantify the effect of delivery size and time windows in urban areas. This project aimed to determine how best to obtain practical and intuitive approximations on the length of commercial vehicle tours and miles traveled in urban areas. Additionally, the project tested various means of estimating the impact of time windows and delivery sizes on commercial VMTs. Close

• 4. [Article] Crowdsourcing Cycling Safety and Route Data with the “ORcycle” Smartphone App

  ORcycle is a new smartphone application (for both Android and iOS) developed by Transportation, Technology, and People (TTP) lab researchers at Portland State University as part of an Oregon Department ...

  Citation × Citation Citation Abstract Copy Title: Crowdsourcing Cycling Safety and Route Data with the “ORcycle” Smartphone App Author: Figliozzi, Miguel Year: 2015 ORcycle is a new smartphone application (for both Android and iOS) developed by Transportation, Technology, and People (TTP) lab researchers at Portland State University as part of an Oregon Department of Transportation (ODOT) research project. ORcycle collects user, route, infrastructure, crash, and safety data. ORcycle was successfully launched in early November 2014 and presents many improvements over existing or similar apps. Initial data findings and insights will be presented. Lessons learned as well as opportunities and challenges associated with smartphone data collection methods will be discussed. More information about the app can be found here: http://www.pdx.edu/transportation-lab/orcycle. Title: Crowdsourcing Cycling Safety and Route Data with the “ORcycle” Smartphone App Author: Figliozzi, Miguel Year: 2015 ORcycle is a new smartphone application (for both Android and iOS) developed by Transportation, Technology, and People (TTP) lab researchers at Portland State University as part of an Oregon Department of Transportation (ODOT) research project. ORcycle collects user, route, infrastructure, crash, and safety data. ORcycle was successfully launched in early November 2014 and presents many improvements over existing or similar apps. Initial data findings and insights will be presented. Lessons learned as well as opportunities and challenges associated with smartphone data collection methods will be discussed. More information about the app can be found here: http://www.pdx.edu/transportation-lab/orcycle. Close

• 5. [Article] Exploiting New Data Sources to Quantify Arterial Congestion and Performance Measures at a Regional Scale

  Transit travel time, operating speed and reliability all influence service attractiveness, operating cost and system efficiency. These metrics have a long-term impact on system effectiveness through a ...

  Citation × Citation Citation Abstract Copy Title: Exploiting New Data Sources to Quantify Arterial Congestion and Performance Measures at a Regional Scale Author: Figliozzi, Miguel, Bertini, Robert L., Glick, Travis B, Stoll, Nicholas B, Feng, Wei, Sidhu, Bobjot S., Pande, Anurag Year: 2017 Transit travel time, operating speed and reliability all influence service attractiveness, operating cost and system efficiency. These metrics have a long-term impact on system effectiveness through a change in ridership. As part of its bus dispatch system (BDS), the Tri-County Metropolitan Transportation District of Oregon (TriMet) has been archiving automatic vehicle location (AVL) and automatic passenger count (APC) data for all bus trips at the stop level since 1997. In 2014, a new and higher-resolution bus AVL data collection system was fully implemented. This new AVL system provides stop-level data as well as five-second resolution (5-SR) bus position data between stops. Rather than relying on interpolation tools to estimate bus trajectories (including stops and delays) between stops, the higher-resolution data shows more precise bus positions along each trip. Bus travel speeds and intersection signal/queuing delays may be determined using this newer information of several variables on transit travel time. This research project explored potential applications of the new data for assessing transit performance, and for estimating transportation system performance measures for urban streets and arterials. Results suggest that the 5-SR data provides high-resolution time and position information which can be used to determine bus travel speeds between stops, identify speed breakdowns, and estimate intersection signal/queuing delays. Additionally, high-resolution achieved bus data can be used to visualize sources of congestion and delay on urban arterials. A new inter-stop trip time model was developed using the five-second resolution data. This newly developed model resulted in statistically significant and improved results over previous models. The models for overall travel time indicated that dwell time and average speed between stops were the major factors influencing transit travel time. Hence, it was concluded that estimation of average speed between stops is a critical component of the transit trip time models. Using this 5-SR data in the trip time model led to more precise and statistically valid trip time models. The research provides conclusions that can be used by transit agencies to improve operations through improvements such as transit signal priority. More importantly, for transit agencies looking for ways to archive data the research provides recommendations on formatting the data that can be most useful for future analysis. Title: Exploiting New Data Sources to Quantify Arterial Congestion and Performance Measures at a Regional Scale Author: Figliozzi, Miguel, Bertini, Robert L., Glick, Travis B, Stoll, Nicholas B, Feng, Wei, Sidhu, Bobjot S., Pande, Anurag Year: 2017 Transit travel time, operating speed and reliability all influence service attractiveness, operating cost and system efficiency. These metrics have a long-term impact on system effectiveness through a change in ridership. As part of its bus dispatch system (BDS), the Tri-County Metropolitan Transportation District of Oregon (TriMet) has been archiving automatic vehicle location (AVL) and automatic passenger count (APC) data for all bus trips at the stop level since 1997. In 2014, a new and higher-resolution bus AVL data collection system was fully implemented. This new AVL system provides stop-level data as well as five-second resolution (5-SR) bus position data between stops. Rather than relying on interpolation tools to estimate bus trajectories (including stops and delays) between stops, the higher-resolution data shows more precise bus positions along each trip. Bus travel speeds and intersection signal/queuing delays may be determined using this newer information of several variables on transit travel time. This research project explored potential applications of the new data for assessing transit performance, and for estimating transportation system performance measures for urban streets and arterials. Results suggest that the 5-SR data provides high-resolution time and position information which can be used to determine bus travel speeds between stops, identify speed breakdowns, and estimate intersection signal/queuing delays. Additionally, high-resolution achieved bus data can be used to visualize sources of congestion and delay on urban arterials. A new inter-stop trip time model was developed using the five-second resolution data. This newly developed model resulted in statistically significant and improved results over previous models. The models for overall travel time indicated that dwell time and average speed between stops were the major factors influencing transit travel time. Hence, it was concluded that estimation of average speed between stops is a critical component of the transit trip time models. Using this 5-SR data in the trip time model led to more precise and statistically valid trip time models. The research provides conclusions that can be used by transit agencies to improve operations through improvements such as transit signal priority. More importantly, for transit agencies looking for ways to archive data the research provides recommendations on formatting the data that can be most useful for future analysis. Close

• 6. [Article] Green and Economic Fleet Replacement Modeling: Part I

  The purpose of this study was to gain a better understanding of how equipment replacement decisions are supported with data collection and quantitative models at state DOTs, and to determine if models ...

  Citation × Citation Citation Abstract Copy Title: Green and Economic Fleet Replacement Modeling: Part I Author: Kim, David S., Figliozzi, Miguel, Porter, J. David Year: 2011 The purpose of this study was to gain a better understanding of how equipment replacement decisions are supported with data collection and quantitative models at state DOTs, and to determine if models found in the research literature offer any better decision support when applied to realistic fleet usage and cost data. This study also addressed the current state of equipment replacement at state DOTs with respect to using measurable “green” criteria in replacement decisions, and the development of new quantitative replacement models utilizing such criteria. The responses from 25 state DOTs indicates that there is little consistency in the criteria used by state DOTs to support replacement decisions and the way that these criteria are used. There are also no measurable “green” criteria utilized. However, most state DOTs maintain an information system where cost and usage data is recorded, stored, and utilized as part of the replacement process. To investigate if a particular modeling approach offers better performance than the variety of approaches used in practice, a simulation study was conducted. Simulation models were used to evaluate the effectiveness of replacement models for prioritizing equipment replacement. The models evaluated come from the research literature and were compared to a simple replacement model that is similar to those used by state DOTs. Results indicate that the simple models used in practice provide similar results to the best model from the research literature. Title: Green and Economic Fleet Replacement Modeling: Part I Author: Kim, David S., Figliozzi, Miguel, Porter, J. David Year: 2011 The purpose of this study was to gain a better understanding of how equipment replacement decisions are supported with data collection and quantitative models at state DOTs, and to determine if models found in the research literature offer any better decision support when applied to realistic fleet usage and cost data. This study also addressed the current state of equipment replacement at state DOTs with respect to using measurable “green” criteria in replacement decisions, and the development of new quantitative replacement models utilizing such criteria. The responses from 25 state DOTs indicates that there is little consistency in the criteria used by state DOTs to support replacement decisions and the way that these criteria are used. There are also no measurable “green” criteria utilized. However, most state DOTs maintain an information system where cost and usage data is recorded, stored, and utilized as part of the replacement process. To investigate if a particular modeling approach offers better performance than the variety of approaches used in practice, a simulation study was conducted. Simulation models were used to evaluate the effectiveness of replacement models for prioritizing equipment replacement. The models evaluated come from the research literature and were compared to a simple replacement model that is similar to those used by state DOTs. Results indicate that the simple models used in practice provide similar results to the best model from the research literature. Close

• 7. [Article] Safety Effectiveness of Pedestrian Crossing Enhancements

  Over the last decade, the Oregon DOT and other agencies have systematically implemented many pedestrian crossing enhancements (PCEs) across the state. This study explored the safety performance of these ...

  Citation × Citation Citation Abstract Copy Title: Safety Effectiveness of Pedestrian Crossing Enhancements Author: Monsere, Christopher M., Figliozzi, Miguel, Kothuri, Sirisha, Razmpa, Ali, Hazel, Daniel R. Year: 2016 Over the last decade, the Oregon DOT and other agencies have systematically implemented many pedestrian crossing enhancements (PCEs) across the state. This study explored the safety performance of these enhanced crossing in Oregon. Detailed data were collected on 191 crossings. Supplemental data items included crossing location information, route characteristics, surrounding land use and crossing enhancement descriptions. Pedestrian volume at the crossing locations was a highly desirable but unavailable data element. To characterize pedestrian activity, a method was developed to estimate ranges for pedestrian crosswalk activity levels based on the land use classification at the census block level and the presence of pedestrian traffic generators such as bus stops, schools, shopping centers and hospitals within a 0.25-mile radius. Each crosswalk was categorized into one of six levels of activity – very low, low, medium-low, medium, medium-high and high. Crash data for the 2007-2014 period were assembled for the safety analysis. After filtering, 62 pedestrian crashes and 746 rear-end crashes were retained for further analysis. The crash data were merged and analyzed. Crash patterns and risk ratios were explored. The most important trend observed was a shift (reduction) in the pedestrian crash severity after the installation of the crosswalk treatments. This shift was from fatal and injury A crash type to lower severity crashes of injury B and injury C. For pedestrian crashes, increases in the risk ratio were observed for increases in the number of lanes, the posted speed, and estimated pedestrian activity level. Similar trends were observed for rear-end crashes. Due to data limitations, subsequent safety analysis focused on installations of RRFB crossing enhancements. A CMF for RRFB installations was estimated. The CMFS for pedestrian crashes are 0.64 +/- 0.26 using a simple before-after analysis; for rear-end crashes: 0.93 +/- 0.22 using an empirical Bayes analysis approach. Title: Safety Effectiveness of Pedestrian Crossing Enhancements Author: Monsere, Christopher M., Figliozzi, Miguel, Kothuri, Sirisha, Razmpa, Ali, Hazel, Daniel R. Year: 2016 Over the last decade, the Oregon DOT and other agencies have systematically implemented many pedestrian crossing enhancements (PCEs) across the state. This study explored the safety performance of these enhanced crossing in Oregon. Detailed data were collected on 191 crossings. Supplemental data items included crossing location information, route characteristics, surrounding land use and crossing enhancement descriptions. Pedestrian volume at the crossing locations was a highly desirable but unavailable data element. To characterize pedestrian activity, a method was developed to estimate ranges for pedestrian crosswalk activity levels based on the land use classification at the census block level and the presence of pedestrian traffic generators such as bus stops, schools, shopping centers and hospitals within a 0.25-mile radius. Each crosswalk was categorized into one of six levels of activity – very low, low, medium-low, medium, medium-high and high. Crash data for the 2007-2014 period were assembled for the safety analysis. After filtering, 62 pedestrian crashes and 746 rear-end crashes were retained for further analysis. The crash data were merged and analyzed. Crash patterns and risk ratios were explored. The most important trend observed was a shift (reduction) in the pedestrian crash severity after the installation of the crosswalk treatments. This shift was from fatal and injury A crash type to lower severity crashes of injury B and injury C. For pedestrian crashes, increases in the risk ratio were observed for increases in the number of lanes, the posted speed, and estimated pedestrian activity level. Similar trends were observed for rear-end crashes. Due to data limitations, subsequent safety analysis focused on installations of RRFB crossing enhancements. A CMF for RRFB installations was estimated. The CMFS for pedestrian crashes are 0.64 +/- 0.26 using a simple before-after analysis; for rear-end crashes: 0.93 +/- 0.22 using an empirical Bayes analysis approach. Close