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.

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 …

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 …

Outdoor Position Recovery From Heterogeneous Telco Cellular Data, Yige Zhang, Weixiong Rao, Kun Zhang, Lei Chen

Machine Learning Faculty Publications

Recent years have witnessed unprecedented amounts of data generated by telecommunication (Telco) cellular networks. For example, measurement records (MRs) are generated to report the connection states between mobile devices and Telco networks, e.g., received signal strength. MR data have been widely used to localize outdoor mobile devices for human mobility analysis, urban planning, and traffic forecasting. Existing works using first-order sequence models such as the Hidden Markov Model (HMM) attempt to capture spatio-temporal locality in underlying mobility patterns for lower localization errors. The HMM approaches typically assume stable mobility patterns of the underlying mobile devices. Yet real MR datasets exhibit …

Low-Cement Concrete Mixture For Bridge Decks And Rails, Soumitra Das, George Morcous Ph.D., Jiong Hu

Nebraska Department of Transportation: Research Reports

Right after construction, drying shrinkage of restrained concrete bridge decks and rails causes early-age cracking, insertion of water and chemicals, and corrosion of reinforcing steel that eventually leads to delamination and spalling of concrete. The main objective of this research is to control early-age shrinkage cracking by reducing cementitious material content in bridge deck and rail concrete mixtures. Several reduced cementitious materials concrete (RCMC) mixtures were developed by optimizing aggregate particle packing and conducting overall performance evaluation. This evaluation was carried out in three phases. The first phase investigated the feasibility of new RCMC mixtures by testing workability, compressive strength, …

Corridor-Wide Surveillance Using Unmanned Aircraft Systems, Yu Zhang, Achilleas Kourtellis, Joseph Post, Hualong Tang, Keerthana Yelchuri, Brian Porter

Research Reports

In the second phase of the project, the research team continued traffic data collection with unmanned aerial systems (UAS) and dual sensors (RGB and thermal cameras) for roadways under normal operational condition and during incident clearance. The research team conducted a thorough literature review of incident detection methods. Based on the review outcomes, the research team extracted traffic features from learning the video data and trained several learning models for identifying non-congestion conditions caused by incidents. This method was tested on a two-minute video with data captured by a drone at a location at which traffic was passing through an …

Analyzing Transportation Amenities In The City Of Shamokin: An Emphasis On The Lower Anthracite Transportation System, Zane Hensal, Jeff Cianfrocca, Kosta Varkaris

Coal Region Field Station Student Projects

As the population gets older, and means of transportation get more expensive, the need for increased public transportation has increased exponentially. To develop recommendations for the Lower Anthracite Transportation System (LATS) in Northumberland County, this report compared various forms of multimodal transportation throughout the United States, and other foreign countries, and compared them with the current standards and practices set by LATS service. According to the United State Census Bureau, Shamokin is a small 3^rd class city in Northumberland County Pennsylvania, with a population of 6,901, a poverty rate of 35.9%, and is in the LATS service area. Shamokin …

The Rise Of Multi-Homing In Asia's Ride-Hailing Industry, Hai Wang

Asian Management Insights

Getting it right secures environmental and economic wins for the present and future.

Roadway Floods And Their Associated Weather-Related Conditions: New Insights Using Cars 511 Data For State And Federal Highways In Nebraska, Usa, Logan R. Bundy, Mark Anderson, Clinton M. Rowe, Rezaul Mamood

Department of Earth and Atmospheric Sciences: Faculty Publications

This study examined roadway flooding event data provided by the Nebraska Department of Transportation via the Condition Acquisition Reporting System (CARS) 511 archive (2016–2021). With these data, a novel analysis was completed to further the understanding of where, when, and why (meteorologically) roadway flooding occurs on Nebraska state and federal highways. In the study period, 298 roadway floods occurred, with an annual median of 16 per year. There was a greater risk for roadway floods to transpire more frequently in eastern Nebraska, which was attributed to the spatial climatology of heavy rainfall and the higher density of roadways and rivers. …

The Carbon Footprint Of Tourist Transportation In Gettysburg National Military Park, Charlie T. Cross, Justin P. Sawina

Student Publications

National Parks have a contradictory mandate to preserve the environment while providing resources for recreation. We studied the emissions of Gettysburg National Military Park (GNMP), specifically: What are the annual and per capita emissions caused by the various forms of transportation within the park? How does the annual and per capita emissions of GNMP compare with other national parks? To study this we compiled visitor statistics from the National Parks Service of vehicle and visitor count. We then observed 165 vehicles at Pickett’s Charge to find a breakdown of tourist vehicle types. These proportions were then used to find the …

Erosion Resistant Rock Shoulder, Chung R. Song, Richard L. Wood, Basil Abualshar, Mark O'Brien, Bashar Al-Nimri, Mitra Nasimi

Nebraska Department of Transportation: Research Reports

Highway shoulder rocks are exposed to continuous erosion force due to unexpected floodings caused by climate change. The evaluation methods of the erosion resistance of highway shoulder rocks are not currently well-developed. This study developed a new large-scale testing device, the University of Nebraska-Lincoln Erosion Testing Bed (UNLETB), which has the capability of testing the shoulder gravels. Different gradations were tested using UNLETB, and the results distinguished a high-resistant group and a low-resistant group. The low resistant group was treated with different binding agents: Ammonium Lignosulfonate (LIGNO10), Soybean Soap Stock, and DirtGlue. The treated samples showed better erosion resistance based …

Inequality Of Air Quality?: A Study Of Air Quality Within Housing Price Brackets In Gettysburg, Pa, Jess G. Schaefer, Alexis J. Jones, Arden H. Dowd

Student Publications

With the rise of cars and other motorized vehicles has come the rise of air pollution, which tends to have disproportionate environmental and health impacts on low-income and communities of color. This study analyzes car presence and air quality on a transect within Gettysburg, PA to determine if there is a relationship between air pollution and vehicle presence, and if there is a difference in air quality between higher price bracket housing compared to campus, commercial, and lower price bracket housing. To test our research questions, we identified nine sampling locations along a transect where we measured air pollutants, including …

Energy Dissipation Optimization For Circular Culverts, David M. Admiraal, Chi Zhang

Nebraska Department of Transportation: Research Reports

Two types of energy dissipation devices at circular culvert outlets were investigated: full-length weirs and staggered weirs. Related literature was reviewed; a model broken-back circular culvert and dissipation basin was built; instrumentation was installed to measure discharge, piezometric head, and velocities; and four sizes of full-length and staggered weirs were tested over a range of discharges and tailwaters. Weir heights ranged from D/8 to 4D/8, in which D was the culvert diameter. The two weir types were subjected to two styles of tests: (1) tests unaffected by tailwater and (2) tailwater-influenced tests. For tall full-length weirs (3D/8 and 4D/8), basin …

Unsupervised Sampling Promoting For Stochastic Human Trajectory Prediction, Guangyi Chen, Zhenhao Chen, Shunxing Fan, Kun Zhang

Machine Learning Faculty Publications

The indeterminate nature of human motion requires trajectory prediction systems to use a probabilistic model to formulate the multi-modality phenomenon and infer a finite set of future trajectories. However, the inference processes of most existing methods rely on Monte Carlo random sampling, which is insufficient to cover the realistic paths with finite samples, due to the long tail effect of the predicted distribution. To promote the sampling process of stochastic prediction, we propose a novel method, called BOsampler, to adaptively mine potential paths with Bayesian optimization in an unsupervised manner, as a sequential design strategy in which new prediction is …

Truck Platooning Effects On Girder Bridges: Phase Ii-Service, Joshua Steelman, Jay Puckett, Daniel Linzell, Bowen Yang

Nebraska Department of Transportation: Research Reports

Truck platooning—wirelessly linking two or more trucks to travel in a closely spaced convoy—is federally promoted to save fuel, improve the environment, and improve traffic operations. Platooning places trucks much closer than current design codes anticipate. While this strategy can provide higher fuel efficiency, it also can potentially overload structures. Previous reliabilitybased studies (Steelman et al., 2021; Yang et al., 2021) have focused on the Strength I limit state and have shown that trucks can operate at weights exceeding standard legal load limits even with short headways at operating-level reliability. However, service limit states in the AASHTO LRFD Bridge Design …

The Heterogeneous Vehicle Routing Problem With Multiple Time Windows For The E-Waste Collection Problem, Aldy Gunawan, Minh P.K Nguyen, Vincent F. Yu, Dang Viet Anh Nguyen

Research Collection School Of Computing and Information Systems

Waste from electrical and electronic equipment (WEEE) or e-waste describes end-of-life electronic products that are discarded. Due to their toxic and negative impacts to humans' health, many publications have been proposed to handle, however, studies related to e-waste collection and transportation to waste disposal sites are not widely studied so far. This study proposes a mixed integer linear programming (MILP) model to solve the e-waste collecting problem by formulating it as the heterogeneous vehicle routing problem with multiple time windows (HVRPMTW). The model is validated with newly developed benchmark instances that are solved by commercial software, CPLEX. The model is …