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Full-Text Articles in Transportation

Sensing Safety: Developing A Flexible, Portable Alcohol Detection Patch For Community Wellness, Ava Hedayatipour, Ryan Huynh, Wahaab Ademola Sep 2026

Sensing Safety: Developing A Flexible, Portable Alcohol Detection Patch For Community Wellness, Ava Hedayatipour, Ryan Huynh, Wahaab Ademola

Mineta Transportation Institute

Alcohol-impaired driving remains one of the leading causes of traffic fatalities and serious injuries in the United States, posing significant challenges to transportation safety and imposing substantial social and economic costs. Although breathalyzers and wearable alcohol monitoring devices can help detect alcohol consumption, many existing technologies are expensive, bulky, or impractical for continuous, long-term monitoring. This study investigates a lowcost electrochemical sensing platform that could support future wearable alcohol monitoring systems for transportation safety applications. Specifically, the report presents the design, fabrication, and experimental evaluation of a custom screen-printed electrode (SPE) integrated with the Texas Instruments LMP91000 potentiostat. Each disposable …


Understanding Mobility-Related Challenges For Aapi Older Adults: A Preliminary Study In Southern California, Yongping Zhang, Priscila Salgado Inzunza, Carol Kachadoorian, Wen Cheng, Calvin Wong Jan 2025

Understanding Mobility-Related Challenges For Aapi Older Adults: A Preliminary Study In Southern California, Yongping Zhang, Priscila Salgado Inzunza, Carol Kachadoorian, Wen Cheng, Calvin Wong

Mineta Transportation Institute

The Federal Highway Administration (FHWA) and state Departments of Transportation (DOTs) Nationwide, the Asian American Pacific Islander (AAPI) community is projected to constitute 11 percent of people 65 years and older in the United States by 2050 (He et al., 2005). The challenges limiting the transportation and mobility of AAPI older adults include, but are not limited to, language barriers, cultural barriers, anti-Asian hate, accessibility to public transit, traffic safety and public security concerns, and changes to mobility due to the COVID-19 pandemic. This project conducted an extensive literature review and a preliminary multi-language survey in Southern California to better …


Artificial Intelligence For Pedestrian And Bicyclist Safety: Using Ai To Detect Near-Miss Collisions, Mohammad Pourhomayoun Oct 2024

Artificial Intelligence For Pedestrian And Bicyclist Safety: Using Ai To Detect Near-Miss Collisions, Mohammad Pourhomayoun

Mineta Transportation Institute

Near-Miss Collisions are events that, with a slight change in position or timing, could have resulted in a collision, which could have caused severe injury or property damage. Understanding near-miss collisions can help identify risks and potentially improve road safety. In this project, we developed an effective end-to-end system based on advanced artificial intelligence (AI) models and computer vision algorithms to detect and report near-miss collisions as an important indicator to identify and measure safety risks, especially in specific circumstances such as a right turn on a red light. The main objective is to improve the safety of pedestrians and …


Hillsboro: Bike And Pedestrian Implementation Recommended Strategy, Maddy Poehlein, Chris Corral, Sierra Willems, Ciara Williams, Lise Ferguson, Shane Seaman Jun 2024

Hillsboro: Bike And Pedestrian Implementation Recommended Strategy, Maddy Poehlein, Chris Corral, Sierra Willems, Ciara Williams, Lise Ferguson, Shane Seaman

Master of Urban and Regional Planning Workshop Projects

This project presents a contextualized Bike and Pedestrian Implementation Strategy for the City of Hillsboro. The goal was to develop an actionable approach to expand and improve the City’s active transportation network. The strategy incorporates 23 criteria for project selection informed by existing conditions and the City’s priorities. Finally, the report culminates with a recommended implementation approach using two top scoring projects as examples.


Improving Pedestrian Safety With The Implementation Of The Demand-Responsive Transverse Rumble Strip As A New Traffic Safety Countermeasure, Md Shakhawat Hossen Dec 2021

Improving Pedestrian Safety With The Implementation Of The Demand-Responsive Transverse Rumble Strip As A New Traffic Safety Countermeasure, Md Shakhawat Hossen

UNLV Theses, Dissertations, Professional Papers, and Capstones

The traditional TRS has been extensively used as a traffic calming device to provide cognitive alerts in the form of sound and vibration to drivers. However, TRS always remains fixed on the road and thus exerts cognitive alerts, irrespective of any potential downstream hazards. Moreover, the continuous exposure to rumble strips has been identified as a source of discomfort and annoyance for drivers, which limits its application to potentially useful scenarios. This study explores a rumble strip design with dynamic behavior named as Demand-Responsive Transverse Rumble Strip (DRTRS) in order to address the limitations of static TRS. The study incorporates …


New Radar Sensor Technology For Intelligent Multimodal Traffic Monitoring At Intersections, Siyang Cao, Yao-Jan Wu, Feng Jin Nov 2021

New Radar Sensor Technology For Intelligent Multimodal Traffic Monitoring At Intersections, Siyang Cao, Yao-Jan Wu, Feng Jin

TREC Project Briefs

Intelligent Transportation Systems (ITS) need traffic data to run smoothly. At intersections, where there is the greatest potential for conflicts between road users, being able to reliably and intelligently monitor the different modes of traffic is crucial.

The Federal Highway Administration estimates that more than 50 percent of the combined total of fatal and injury crashes occur at or near intersections. For pedestrians the intersection is a particularly dangerous place: the City of Portland, OR identified that two-thirds of all crashes involving a pedestrian happen at intersections. And when darkness comes earlier in fall and winter, crashes increase dramatically. So …


Development Of Intelligent Multimodal Traffic Monitoring Using Radar Sensor At Intersections, Siyang Cao, Yao-Jan Wu, Feng Jin Nov 2021

Development Of Intelligent Multimodal Traffic Monitoring Using Radar Sensor At Intersections, Siyang Cao, Yao-Jan Wu, Feng Jin

TREC Final Reports

Multimodal traffic monitoring is critical for improving mobility and safety at intersections with potential conflicts among various modes of transportation. Traditional traffic monitoring approaches utilizing cameras cannot work reliably during the night and under hazardous weather conditions. We propose to build a new intelligent multimodal traffic monitoring device using the low-cost mmWave radar. The proposed device can reliably distinguish different modes (such as buses, pedestrians, bicyclists, trucks, motorcycles, etc.), and determine the counts, speed, and moving directions of every single target in an urban environment under various lighting and weather conditions. In the study, a low-cost prototype system will also …


Eisenhower And The Interstate, Brian H. Berry Oct 2021

Eisenhower And The Interstate, Brian H. Berry

Student Publications

By passing the Federal Highway Act of 1956, 34th U.S. President Dwight D. Eisenhower would go down in history as the father of the American Interstate Highway System. It was Ike’s determination to execute his ‘Grand Plan’ for a modernized road network that initiated the monumental effort to produce the roads we as Americans use every day. However, today’s highway network is a far cry from what Ike had in mind when he first envisioned the plan. Congressional dissent and special interests did much to undermine the success of Ike’s ‘Grand Plan,’ forcing him to compromise significantly on the issue. …


Data-Driven Mobility Strategies For Multimodal Transportation, Yao-Jan Wu, Xianfeng Terry Yang, Sirisha Kothuri, Abolfazl Karimpour, Qinzheng Wang, Jason Anderson Aug 2021

Data-Driven Mobility Strategies For Multimodal Transportation, Yao-Jan Wu, Xianfeng Terry Yang, Sirisha Kothuri, Abolfazl Karimpour, Qinzheng Wang, Jason Anderson

TREC Final Reports

Multimodal transportation systems (e.g., walking, cycling, automobile, public transit, etc.) are effective in increasing people’s travel flexibility, reducing congestion, and improving safety. Therefore, it is critical to understand what factors would affect people’s mode choices. With advanced technology, such as connected and automated vehicles, cities are now facing a transition from traditional urban planning to developing smart cities. To support multimodal transportation management, this study will serve as a bridge to connect speed management strategies of conventional corridors to connected vehicle corridors. This study consists of three main components. In the first component, the impact of speed management strategies along …


Enhancement Of Multimodal Traffic Safety In High-Quality Transit Areas, Yongping Zhang, Wen Cheng, Xudong Jia Feb 2021

Enhancement Of Multimodal Traffic Safety In High-Quality Transit Areas, Yongping Zhang, Wen Cheng, Xudong Jia

Mineta Transportation Institute

Numerous extant studies are dedicated to enhancing the safety of active transportation modes, but very few studies are devoted to safety analysis surrounding transit stations, which serve as an important modal interface for pedestrians and bicyclists. This study bridges the gap by developing joint models based on the multivariate conditionally autoregressive (MCAR) priors with a distance-oriented neighboring weight matrix. For this purpose, transit-station-centered data in Los Angeles County were used for model development. Feature selection relying on both random forest and correlation analyses was employed, which leads to different covariate inputs to each of the two jointed models, resulting in …


Applying Data-Driven Multimodal Speed Management Strategies For Safe, Efficient Transportation, Yao-Jan Wu, Xianfeng Yeng, Sirisha Kothuri Jan 2021

Applying Data-Driven Multimodal Speed Management Strategies For Safe, Efficient Transportation, Yao-Jan Wu, Xianfeng Yeng, Sirisha Kothuri

TREC Project Briefs

How can we use a variety of data-driven speed management strategies to make transportation safer and more efficient for all modes–whether you’re driving, walking or taking transit? The project was led by Yao Jan Wu, director of the Smart Transportation Lab at the University of Arizona. Co-investigators were Xianfeng Terry Yang of the University of Utah, who researches traffic operations and modeling along with connected automated vehicles, and Sirisha Kothuri of Portland State University, whose research has focused on improving signal timing to better serve pedestrians. “We want to improve mobility for all users, be it pedestrians, vehicle drivers or …


Impact Of Regular And Narrow Av-Exclusive Lanes On Manual Driver Behavior, Sahar Ghanipoor Machiani, Aryan Sohrabi, Arash Jahangiri Oct 2020

Impact Of Regular And Narrow Av-Exclusive Lanes On Manual Driver Behavior, Sahar Ghanipoor Machiani, Aryan Sohrabi, Arash Jahangiri

Mineta Transportation Institute

This study attempts to answer the question of how a narrow (9-ft) lane dedicated to Automated Vehicles (AVs) would affect the behavior of drivers in the adjacent lane to the right. To this end, a custom driving simulator environment was designed mimicking the Interstate 15 smart corridor in San Diego. A group of participants was assigned to drive next to the simulated 9-ft narrow lane while a control group was assigned to drive next to a regular 12-ft AV lane. Driver behavior was analyzed by measuring the mean lane position, mean speed, and mental effort (self-reported/subjective measure). In addition to …


Automatic Traffic Monitoring And Management For Pedestrian And Cyclist Safety Using Deep Learning And Artificial Intelligence, Mohammad Pourhomayoun Sep 2020

Automatic Traffic Monitoring And Management For Pedestrian And Cyclist Safety Using Deep Learning And Artificial Intelligence, Mohammad Pourhomayoun

Mineta Transportation Institute

In this project, we have designed and developed an effective end-to-end system based on advanced Artificial Intelligence (AI), machine learning, and computer vision to automatically monitor, detect, track, and count pedestrians and bicyclists. The main objective of this project is to improve the safety of pedestrians and bicyclists, by applying self-sensed and AI-powered systems to monitor and control the flow of pedestrians/bicyclists. The developed system includes algorithms for detecting the pedestrians and bicyclists, as well as algorithms for tracking and counting the pedestrians. We evaluated the developed system on real videos captured by actual traffic cameras in the city of …


A No-Crash Course In Vision Zero Data, Anamaria Perez Apr 2020

A No-Crash Course In Vision Zero Data, Anamaria Perez

PSU Transportation Seminars

Vision Zero was adopted unanimously by Portland City Council in 2015 with the goal of eliminating traffic deaths and serious injuries on Portland streets in a way that is equitable, accountable, and data-driven. But what does it mean to be data-driven? And should we stop there?

In this presentation, learn how Portland’s Vision Zero Action Plan was developed and how the Vision Zero team is using data to move into a future where all Portlanders can travel safely, regardless of the travel mode they use. Explore the datasets used in Vision Zero implementation and the challenges that come with them. …


The Safe System Approach: Considerations For Developing A Multi-Layered System, Offer Grembek Oct 2019

The Safe System Approach: Considerations For Developing A Multi-Layered System, Offer Grembek

PSU Transportation Seminars

While the overarching objective of the transportation system is to provide mobility, it should be developed and operated under the framework of a safe system with the aspirational goal to establish a system on which no road user can be severely or fatally injured. To accomplish such a safe system, it is necessary to effectively harness all the core protective opportunities provided by the system. This includes the street design and operations, user behavior, vehicle design, protection systems, and EMS. The common thread across these layers is speed. This is directly driven by the quadratic relationship between velocity and kinetic …


Evaluation Of Bus/Bicycle Andbus/Right-Turn Traffic Delays And Conflicts, Miguel A. Figliozzi, Katherine Keeling, Travis Glick Oct 2019

Evaluation Of Bus/Bicycle Andbus/Right-Turn Traffic Delays And Conflicts, Miguel A. Figliozzi, Katherine Keeling, Travis Glick

TREC Final Reports

This research evaluates conflicts and delays caused by interactions between buses, bicycles, and right-turningvehicles. Two concerns caused by these overlapping bus, bicycle, and automobile facilities are analyzed; the firstconcern is the number of bus-bicycle conflicts (as a proxy for safety) and the second concern is bus delay. Video datawas collected and analyzed to quantify conflicts, travel time, and delay. For every bus passing through the study site,the mixed-traffic scenario that the bus incurs was categorized as one of 72 different combinations of bus, bicycle, andautomobile interactions. Video count data was weighted according to seasonal, weekly, and hourly bicycle volumedata to …


Modeling Driver-Pedestrian-Infrastructure Interactions At Signalized Midblock Crosswalks, Boniphace Kutela May 2019

Modeling Driver-Pedestrian-Infrastructure Interactions At Signalized Midblock Crosswalks, Boniphace Kutela

UNLV Theses, Dissertations, Professional Papers, and Capstones

Cities and metropolitan areas are increasingly facilitating pedestrians’ movement by the provision of pedestrian walking facilities. As pedestrian traffic increases, the risk of crash involvement increases, especially at midblock locations, where pedestrians are exposed to unsafe interactions with vehicular traffic. To improve pedestrians’ safety at midblock locations, various countermeasures are provided, which include signalized crosswalks. Several studies have analyzed driver-pedestrian interactions, as well as pedestrian-infrastructure interactions at signalized midblock crosswalks. However, more in-depth studies are necessary, due to shortfalls of study assumptions, which have led to the application of improper statistical models, as seen in the literature. Improved models are …


Webinar: Rethinking Streets For Bikes: An Evidence Based Guide Of Bike-Friendly Street Retrofits, Marc Schlossberg, Roger Lindgren Feb 2019

Webinar: Rethinking Streets For Bikes: An Evidence Based Guide Of Bike-Friendly Street Retrofits, Marc Schlossberg, Roger Lindgren

TREC Webinar Series

There is a growing demand for better infrastructure and fewer barriers to biking and other forms of space-efficient micromobility. Tackling daily trips by bike is easier on the environment, healthier for users and non-users alike, uses precious urbanized public and private land more efficiently, costs taxpayers less to build and maintain infrastructure, and when routes are safe and comfortable, moving by bike is also fun! Complete Streets policies are being adopted across the country, and there is an active conversation around the safety imperative of a Complete Streets approach. Yet, local officials often need both design guidance and the …


Pedestrian Safety On San Jose Roads: The Impact Of Traffic Safety Infrastructure, David Lisenbee Apr 2018

Pedestrian Safety On San Jose Roads: The Impact Of Traffic Safety Infrastructure, David Lisenbee

Master's Projects

How successful have the City of San Jose’s traffic safety improvement programs been in reducing pedestrian injuries/fatalities on city streets? This research question focuses on the impact of the City of San Jose’s traffic safety programs on pedestrian safety between 2010 and 2014. The research aims to determine the extent to which traffic safety programs and infrastructure reduce rates of pedestrian injuries/fatalities and the severity of pedestrian injuries when incidents occur.


Designing Road Diet Evaluations: Lessons Learned From San Jose’S Lincoln Avenue Road Diet, Hilary Nixon, Asha Weinstein Agrawal, Cameron Simons Jul 2017

Designing Road Diet Evaluations: Lessons Learned From San Jose’S Lincoln Avenue Road Diet, Hilary Nixon, Asha Weinstein Agrawal, Cameron Simons

Mineta Transportation Institute

This report analyzes traffic impacts from the 2015 implementation of a pilot “road diet” on Lincoln Avenue, in the City of San Jose, California, comparing data on traffic volumes and speeds from before and after the road diet was implemented. The analysis looks at impacts on both the road diet location itself and on surrounding streets likely to have been impacted by traffic diverted off the road diet segment. The results within the road diet zone were as expected, with falling volumes and numbers of speeders. The all-day data aggregated by street type (e.g., neighborhood streets, major streets) showed limited …


Webinar: Economic Impacts From Bicycle And Pedestrian Street Improvements, Jenny H. Liu Apr 2017

Webinar: Economic Impacts From Bicycle And Pedestrian Street Improvements, Jenny H. Liu

TREC Webinar Series

As many cities are investing in street improvements to provide better biking and walking experiences, the economic value and impacts of these active transportation facilities remain areas where many practitioners, planners and policy makers are seeking more conclusive evidence. With various modes competing for scarce resources, planners and transportation agencies often struggle with how to justify infrastructure investments for non-motorized modes, particularly when driving is still the predominant mode of transportation in most cities.

In this project we assess property value impacts of Portland’s “Green Loop” signature bike infrastructure concept, illustrating the importance of considering both accessibility and extensiveness of …


Exploring Factors Contributing To Lane Changes During Left Turns On Quadruple Left-Turn Lanes At Signalized Intersections, Fulu Wei, Zhenyu Wang, Jian Lu Jan 2017

Exploring Factors Contributing To Lane Changes During Left Turns On Quadruple Left-Turn Lanes At Signalized Intersections, Fulu Wei, Zhenyu Wang, Jian Lu

CUTR Faculty Journal Publications

Quadruple left-turn lanes are employed gradually at some major intersections in Jilin, China. At these intersections, frequent lane changes during left turns of vehicles can lead to vastly disordered traffic operations. In this study, the factors contributing to lane changes during left turn behaviors at quadruple left-turn lane intersections were interpreted based on a field survey. In total, data on 192 green intervals and 550 individual lane-change behaviors were collected in Changchun, Jilin Province. A lane-changing rate model was established to predict the rate of lane changes during left turns. In addition, an interval selection model was built to estimate …


Lessons From The Development Of A Guidebook On Pedestrian And Bicycle Connections To Transit, Nathan Mcneil, Allison Boyce Duncan, Drew Devitis Nov 2016

Lessons From The Development Of A Guidebook On Pedestrian And Bicycle Connections To Transit, Nathan Mcneil, Allison Boyce Duncan, Drew Devitis

PSU Transportation Seminars

To improve safety and increase transit use, transit agencies and the jurisdictions they serve have to approach transit service as door-to-door not just stop-to-stop.

Walking and bicycling are key modes for transit access.

Working with the Federal Transit Administration, a team from Portland State University developed a guidebook on improving pedestrian and bicycle access to transit (forthcoming). As part of the guidebook process, the PSU team conducted case studies on best practices of recent efforts in Minneapolis, Los Angeles and Atlanta.

This presentation will cover key lessons from the case studies, along with an overview of the guidebook.


Investigating The Relationship Between Latent Driving Patterns And Traffic Safety Using Smartphone-Based Mobile Sensor Data, Kenneth Wynne Apr 2016

Investigating The Relationship Between Latent Driving Patterns And Traffic Safety Using Smartphone-Based Mobile Sensor Data, Kenneth Wynne

Civil & Environmental Engineering Theses & Dissertations

Crash frequency modelling has been used in the past as an attempt to quantify the expected number of crashes occurring on a certain segment of roadway given a set of variables and factors describing the roadway segment and the traffic along that segment. These models are referred to as the Safety Performance Functions (SPFs) in the Highway Safety Manual (HSM). In past studies, these SPFs have focused primarily on roadway geometric information along with limited traffic exposure data such as traffic volume. Alternate data sources for probe vehicle data are increasingly available and this research sought to exploit this new …


Geometric Design, Speed, And Safety, Richard J. Porter Apr 2015

Geometric Design, Speed, And Safety, Richard J. Porter

PSU Transportation Seminars

In this seminar, Dr. Porter will explore the interactions of geometric design decisions, speed, and safety. A performance-based approach to this topic will be considered given the availability of several key documents, including the Highway Safety Manual and TRB's Modeling Operating Speed: Synthesis Report as well as a significant body of published research. A historical look at the design speed concept will show that while the design speed definition has changed on more than one occasion, the same basic but flawed philosophy that relates design speed to a “safe speed” is still reflected in supplemental guidance related to design speed …


Pedestrian Safety And Culture Change, Ron Van Houten May 2014

Pedestrian Safety And Culture Change, Ron Van Houten

PSU Transportation Seminars

This session will describe the process and results of a NHTSA study that showed a change in driver culture of yielding to pedestrians in crosswalks on a citywide basis. The research won the Pat Waller award from the National Academy of Sciences, Transportation Research Board in January of this year. The approach to changing road user behavior focused on an integrated approach that include Enforcement, Engineering, and Educational efforts that were designed to be dovetailed together and that included a social norming component. Additional information will be provided on engineering solutions that can facilitate changes in pedestrian level of service …


Simultaneous Equation Modeling For Crash Rate Of Freeway Segments, Anthony Ramos May 2014

Simultaneous Equation Modeling For Crash Rate Of Freeway Segments, Anthony Ramos

UNLV Theses, Dissertations, Professional Papers, and Capstones

In 2010, the total number of reported traffic crashes in the state of Nevada was 51,664 of which 235 (0.6%) resulted in one or more deaths (Nevada Department of Transportation, 2012). The state's "Zero Fatalities" traffic safety campaign aims to reduce the rate even further. Out of the total number of crashes, Clark County (includes Las Vegas) accounted for 78.89%. This study examines safety improvement by developing advanced crash prediction models. The system of crash prediction equations consider geometric conditions and traffic volume using simultaneous equation modeling (SEM). The models are based on geometric characteristics and traffic volume data collected …


Study Of Seat-Belt Usage In Nevada & Driver's Performance, Atul Sancheti Dec 2013

Study Of Seat-Belt Usage In Nevada & Driver's Performance, Atul Sancheti

UNLV Theses, Dissertations, Professional Papers, and Capstones

According to the Centers for Disease Control (CDC), motor vehicle incidents has been reported to be the leading cause of the accidental deaths in the United States accounting for more than 42,000 deaths every year. Distracted driving and Driving under influence (DUI) are the major contributors to these roadway crashes. Moreover, drivers fatigue and drowsiness behind the wheel is another important factor contributing to the high fatality rate. These factors results in significant decline in the driver's abilities of perception, recognition and vehicle control.

It has also been reported by National Highway Traffic Safety Administration (NHTSA) estimated that about 292,471 …


Influence Of Road Cross Section On Access Spacing, Karen K. Dixon, Yanfen Zhou, J. L. Gattis Oct 2013

Influence Of Road Cross Section On Access Spacing, Karen K. Dixon, Yanfen Zhou, J. L. Gattis

TREC Final Reports

This report presents a study on the influences of select cross-sectional-related design elements (specifically median configurations and bicycle lanes) and their impact on crash severity and type, as well as the associated driver gap acceptance for turning maneuvers at midblock driveway locations on urban arterials. The primary goal of this proposed research is to better understand how the median and bicycle lane configurations can influence safety and operations at driveway locations. The research team utilized crash data, traffic data, and roadway information from driveway locations in the U.S. states of Oregon, Arkansas and Oklahoma. The project team supplemented the data …


A Visualization Tool For A Highway Safety Management System, Indira Khanal, Naveen Veeramisti, Justin Baker, Alexander Paz Apr 2013

A Visualization Tool For A Highway Safety Management System, Indira Khanal, Naveen Veeramisti, Justin Baker, Alexander Paz

College of Engineering: Graduate Celebration Programs

  • With lot of research, Federal Highway Administration
    has released a highway Safety management System
    software called as SafetyAnalyst (SA)
  • SA has a suite of analytical tools to identify and
    manage system-wide safety improvements:
    Network Screening
    Diagnosis and Countermeasure Selection
    Economic Analyses and priority Ranking
    Countermeasure Evaluation
  • SA provides a very rudimentary approach to display
    results just in tabular and textual format
  • This study proposes a visualization tool that expands
    the output capabilities provided by SafetyAnalyst