Digital Commons Network^™

Effect Of Antioxidant Additives And Recycling Agents On Performance Of Asphalt Binders And Mixtures - Phase I, Nitish R. Bastola, Mahdieh Khedmati, Hamzeh Haghshenas, Jamilla Teixeira

Nebraska Department of Transportation: Research Reports

The use of reclaimed asphalt pavement (RAP) in asphalt mixtures has notably increased in recent times. Nevertheless, the inherent stiff and aged characteristics of RAP materials have consistently raised concerns regarding cracking performance. The use of recycling agents (RAs) has gained popularity in recent years since they can effectively modify the engineering properties of the aged asphalt binder. Besides that, the combination of RA with antioxidant (AO) additives has shown promise in enhancing the long-term performance of RAP mixtures. This research aims to investigate the effect of various RAs and one AO additive on performance of asphalt binders and high-RAP …

Bikeability Disparities In Orange County, California: Intersection Of Place And Demographics, Jeanette Gritton, Maria Cristina Martinez, Georgiana Bostean, Megan Thiele Strong

Sociology Faculty Articles and Research

Active transportation modes such as walking and biking are gaining popularity for their extensive health and environmental benefits, yet scholars know little about how place-based accessibility varies by area sociodemographic composition. This study is among the first to examine sociodemographic disparities (by both race and socioeconomic status) in bikeability while allowing for heterogeneity in disparities. Consideration of bikeability disparities is particularly critical within the framework of urban planning concepts that promote equitable accessibility and reduced dependency on automobiles, such as the 15-minute city. Geographically Weighted Regressions examined associations between census tract-level bikeability (using an index that combines five components), socioeconomic …

Modeling Pedestrian And Bicyclist Crash Exposure With Location-Based Service Data, Yunwoo Nam, Jason Hawkins, Don Butler, Nicholas Aldridge, Mohammad Elayan, Kwant Il (Jason) Yoo

Nebraska Department of Transportation: Research Reports

The rising popularity of non-motorized transportation has brought about safety risks. The inclusion of accurate traffic volume information is one of the key elements to produce robust outcomes when researching safety. The project investigates and enhances transportation safety for pedestrians and bicyclists, emphasizing the integration of Location-Based Services (LBS) data, particularly StreetLight data, to analyze traffic volume and associated risks. The calibration process demonstrates the significance of traffic volume as a key variable influencing prediction accuracy across pedestrian, bicyclist, and vehicle models. The crash analysis reveals a strong correlation between crash counts and traffic activity, with noteworthy findings emerging at …

Traffic Sign Extraction From Mobile Lidar Point Cloud, Yushin Ahn, Riadh Munjy, Ziyuan Li

Mineta Transportation Institute

The extraction of traffic signs from Mobile Light Detection and Ranging (LiDAR) point cloud data has become a focal point in transportation research due to the increasing integration of LiDAR technologies. LiDAR, a remote sensing technology, captures detailed three-dimensional point cloud data, offering a comprehensive view of the surrounding environment. Mobile LiDAR systems mounted on vehicles enable efficient data collection, particularly for large-scale road networks. This study aims to develop and refine techniques for extracting traffic signs from Mobile LiDAR point cloud data, essential for enhancing road safety, navigation systems, and intelligent transportation solutions. By leveraging LiDAR technology, new possibilities …

America At A Glance: Travel Patterns By Disability And Rurality, Luke Santore, Andrew Myers, University Of Montana Rural Institute

Independent Living and Community Participation

RTC:Rural researchers use 2022 National Household Transportation Survey (NHTS) data to assess differences in travel behavior across disability status and rurality.

Investigating Rural Traffic Dynamics: A Traffic Study On E 2nd Street Intersection’S Behavior And Safety, Ma Anjelika Rose T. Pineda

2024 Spring Honors Capstone Projects

Traffic studies guide engineers in designing road networks to ensure smooth traffic flow and public safety. Such studies assess the need for traffic control devices to manage vehicle flow safely and efficiently. This is crucial at intersections which pose high risks of collision and congestion. A traffic analysis at the intersection of Island Grove and E 2nd Street on the FM-4 roadway in Cleburne, TX was conducted to evaluate the sufficiency of the current traffic control device. TxDOT warrants and standards and a field study were utilized and performed to justify the substitution for a traffic signal at the intersection. …

Innovation In Transportation Services For Older Adults Aging In Place, Tanya Vintimilla

Capstone Research Posters

As the global population ages, challenges with providing efficient and accessible transportation services for seniors aging in place become increasingly evident. This research paper explores innovative solutions to address the unique mobility and diverse needs of older adults, aiming to maintain their independence, social engagement and overall quality of life. Through a qualitative investigation that combines literature reviews and expert interviews, this study identifies the central relationship between universal design and service delivery in the form of transportation services. This study will serve as the focal point of ideas for innovation in transportation services, contributing to future changes that shape …

Public Cleanliness Satisfaction Survey 2023, Paulin Straughan, Mathews Mathew

Research Collection School of Social Sciences

The Singapore Management University undertook the sixth wave of the Public Cleanliness Satisfaction Survey (PCSS) with 2,010 Singapore residents providing responses to the survey from November 2023 to January 2024.

Similar to the findings from the 2022 wave of PCSS, the 2023 wave of the PCSS continued to reflect an overall satisfaction with public cleanliness in Singapore. Majority of survey respondents (94%) were satisfied with the cleanliness of public spaces that they had recently visited, which was an increase of 2% from 2022. Satisfaction with the cleanliness of food outlets saw the largest increase (by 3%) among all location types, …

Strengthening The Deployment Of Uncrewed Aerial Systems (Uas) At Kytc, Rachel Catchings, Suzanne Smith, Gayle Marks, Candice Wallace, Christopher Van Dyke

Kentucky Transportation Center Research Report

The Kentucky Transportation Cabinet (KYTC) and transportation agencies around the United States increasingly depends on uncrewed aircraft systems (UAS — also commonly known as drones) to collect data and accelerate project development and delivery. Drones let transportation practitioners safely and efficiently perform many activities, including bridge and highway inspection, construction monitoring, surveying, emergency response, and measuring stockpiles. KYTC’s implementation of UAS has expanded rapidly over the past 10 years, however, the agency lacks well-coordinated procedures for connecting pilots with end data users, scheduling and conducting flights, developing and documenting best practices, and processing and storing data. Based on a review …

Evaluation Of Ndot’S Sediment Barrier Practices Using Performance Data, Michael A. Perez, Wesley N. Donald, J. Blake Whitman, Brian G. Roche

Nebraska Department of Transportation: Research Reports

To protect waterways adjacent to construction projects with disturbed land, a 50 ft (15 m) vegetated buffer or equivalent sediment controls are required. However, there is little guidance on the effectiveness of vegetated buffers in removing sediment or how sediment barriers can aid shorter buffers or replace buffers. A modeling methodology was developed and used to determine the performance of 11,664 50 ft (15 m) vegetated buffer configurations with Nebraska conditions; sediment capture averaged 92.6% and ranged from 18.5% to 99.5%. To determine the performance of Nebraska Department of Transportation standard and modified sediment barrier installations, a large-scale testing methodology …

Semi-Decentralized Inference In Heterogeneous Graph Neural Networks For Traffic Demand Forecasting: An Edge-Computing Approach, Mahmoud Nazzal, Abdallah Khreishah, Joyoung Lee, Shaahin Angizi, Ala Al-Fuqaha, Mohsen Guizani

Machine Learning Faculty Publications

Prediction of taxi service demand and supply is essential for improving customer experience and provider's profit. Recently, graph neural networks (GNNs), modeling city areas as nodes in a transportation graph, have been shown efficient for this application as they utilize both local node features and the graph structure in the prediction. Still, further improvement can be achieved by either simultaneously exploiting different types of nodes/edges in the graphs or enlarging the scale of the transportation graph. However, both alternatives are challenged by the scalability of GNNs. An immediate remedy to the scalability challenge is to decentralize the GNN operation. In …

Optimal Algorithm For Managing On-Campus Student Transportation, Youssef Harrath Dr.

Research & Publications

This study analyzed the transportation issues at the University of Bahrain Sakhir campus, where a bus system with an unorganized and fixed number of buses allocated each semester was in place. Data was collected through a survey, on-site observations, and student schedules to estimate the number of buses needed. The study was limited to students who require to move between buildings for academic purposes and not those who choose to ride buses for other reasons. An algorithm was designed to calculate the optimal number of buses for each time slot, and for each day. This solution could improve transportation efficiency, …

Development Of Guideline For The Use Of Geosynthetics In Different Roadway Layered System In Nebraska, Jongwan Eun, Seunghee Kim, Daniel Robertson, Yusuf Alhowaidi, Hung Van, Laith Ibdah

Nebraska Department of Transportation: Research Reports

This study evaluated the design properties of the geosynthetic reinforced soils for the roadway pavement and compared the reinforcing performance depending on different geosynthetics and soil types, particularly for a subgrade layer in Nebraska. The results obtained from a large direct shear test, pullout test, and soil chamber test with a dynamic cone penetrometer (DCP) showed that geosynthetic improves soil properties associated with the pullout and interface shear resistance, strength related parameters. The Large Scale Tracking Wheel Test also showed how the performance of biaxial geogrid reinforced pavement improved the strength/stiffness and reduced the total permanent deformation and pressure acting …

Green Amendments Land Use And Transportation: What Could Go Wrong?, Michael Lewyn

Scholarly Works

Numerous states have amended their constitutions to include a green amendment (that is, an amendment providing that the state's citizens have a right to a healthy environment). Unfortunately, the vagueness of these amendments leaves an enormous amount of interpretative power to courts. This article examines how some courts have interpreted green amendments and how these interpretations risk the misuse of green amendments. Additionally, this article examines how such misuse may be avoided.

A Charging Strategy For Large Commercial Electric Vehicle Fleets, Bassam Al-Hanahi, Iftekhar Ahmad, Daryoush Habibi, Pravakar Pradhan, Mohammad A. S. Masoum

Research outputs 2022 to 2026

The popularity of Commercial Electric Vehicles (CEVs) has experienced a surge in recent years, particularly in urban vocational contexts, as a means of advancing towards the goal of attaining net-zero emissions by 2050. The return-to-base charging strategy, which involves charging CEVs at depots, has become a prevalent practice for smaller CEV fleets. Nevertheless, for larger CEV fleets, the limited charging capacity at depots presents a significant challenge, leading to a reliance on both limited depot charging infrastructure and public charging infrastructure. This reliance can have a substantial impact on both the operational costs and the sustainability of logistics services. To …

Patient Autonomy, Public Safety, And Drivers With Cognitive Decline, Sharona Hoffman, Cassandra Burke Robertson

Faculty Publications

With a growing elderly population, cognitive decline in drivers has become a significant public safety concern. Currently, over thirty-two million individuals who are seventy or older have driver’s licenses, and that number is growing quickly. In addition, almost ten percent of U.S. seniors (those sixty-five and older) have dementia, and an additional twenty-two percent have mild cognitive impairment. Between a quarter and a half of individuals with mild to moderate dementia still drive. As cognitive abilities such as memory, attention, and decision-making skills deteriorate, a driver's ability to operate a vehicle safely can be compromised. This not only puts the …

Segac: Sample Efficient Generalized Actor Critic For The Stochastic On-Time Arrival Problem, Honglian Guo, Zhi He, Wenda Sheng, Zhiguang Cao, Yingjie Zhou, Weinan Gao

Research Collection School Of Computing and Information Systems

This paper studies the problem in transportation networks and introduces a novel reinforcement learning-based algorithm, namely. Different from almost all canonical sota solutions, which are usually computationally expensive and lack generalizability to unforeseen destination nodes, segac offers the following appealing characteristics. segac updates the ego vehicle’s navigation policy in a sample efficient manner, reduces the variance of both value network and policy network during training, and is automatically adaptive to new destinations. Furthermore, the pre-trained segac policy network enables its real-time decision-making ability within seconds, outperforming state-of-the-art sota algorithms in simulations across various transportation networks. We also successfully deploy segac …