Engineering Commons^™

Integrating Artificial Intelligence For Transportation Cyber-Physical Systems: From Detection To Cyber Resilience, Reek Majumder

All Dissertations

This dissertation investigates different methods for methane detection using unmanned aerial vehicles (UAVs). The author addresses the fundamental problem of methane emissions, a potent greenhouse gas responsible for global warming. The first part of the dissertation aims to create a cost-effective system for real-time methane detection and intensity prediction using ensemble learning models trained on meteorological parameters. The ensemble learning-based classification models show a high accuracy for methane detection.

The second part of the dissertation investigates cyberattack detection for UAVs using a graph-based intrusion detection system (IDS) for controller area networks (CAN). This lightweight, protocol-independent IDS uses graph-based machine learning …

Understanding Conversion Of Long Chain Fatty Acids In Anaerobic Digestion Systems, Julia Ann Funk

All Dissertations

Anaerobic co-digestion with fats, oils, and grease (FOG) waste can increase energy production due to the high methane potential of lipids. However, adding FOG can lead to operational issues caused by accumulating saturated long-chain fatty acids (LCFA). My research explored why saturated LCFAs are often the primary intermediate that accumulates and the microbial sensitives of the populations responsible for their degradation. In each batch or semi-continuous experiment, all intermediates of FOG degradation, including LCFAs, volatile fatty acids (VFAs), Hydrogen gas (H₂), and endpoint methane production, were paired with temporal quantitative polymerase chain reaction (qPCR) of the Syntrophomonas genus …

Assessment Of Energy Efficiency Measures Recommended For Industrial Facilities: Environmental, Economic, And Life Cycle Perspectives, Dariush Jafari

Department of Civil and Environmental Engineering: Dissertations, Theses, and Student Research

This study assesses the economic, environmental, and life cycle impacts of more than 800 industrial Energy Efficiency Measures (EEMs) identified in manufacturing facilities across Nebraska. These EEMs are notable for their rapid implementation and minimal disruption to the facility’s building structure or core processes.

The research evaluates the financial viability of EEMs by analyzing utility savings, implementation costs, and payback periods. It also examines their cost-effectiveness in reducing greenhouse gas (GHG) emissions, including calculations of net cost and cost of mitigated CO₂-eq.

Key findings indicate that adding insulation to hot pipes and buildings, replacing personal fans with High-Volume, Low-Speed (HVLS) …

Mash Crashworthiness Of Work Zone Devices And Breakaway Luminaire Poles, Mohammadreza Rajaee

Department of Civil and Environmental Engineering: Dissertations, Theses, and Student Research

This thesis presents a study on the crashworthiness of two commonly-used roadside safety devices: Type II barricades and luminaire poles supported by TB1-17 transformer bases. The first part focuses on designing and evaluating a non-proprietary, Type II barricade that meets MASH criteria. A validated LS-DYNA model, based on a previously-tested Type III barricade, was used to guide the design. The proposed Type II system was evaluated through simulation and confirmed with full-scale crash testing. The second part of the study investigates luminaire poles supported by the TB1-17 transformer base. A previously-developed LS-DYNA model was updated and validated using test No. …

A Framework For Quantifying The Benefits Of Electric Vehicle Infrastructure Development, Donya Negahbani

Department of Civil and Environmental Engineering: Dissertations, Theses, and Student Research

Under the Biden Administration’s Justice40 Initiative, a significant portion of benefits derived from federal clean transportation investments is required to be directed to disadvantaged communities. Meeting this mandate necessitates a transparent and reproducible approach that quantifies various dimensions of value and allocates them equitably. This dissertation presents a flexible framework specifically tailored for the deployment of electric vehicle charging infrastructure in Nebraska, effectively translating equity goals into rigorous spatial and economic analyses. The framework first identifies multiple distinct categories of benefit that reflect the societal value of charging access: energy savings, economic opportunities, environmental quality enhancements, and public health improvements. …

Development Of Timber Bridge Railing And Approach Guardrail Transition, Aaron Lechtenberger

Department of Civil and Environmental Engineering: Dissertations, Theses, and Student Research

Timber bridges with transverse and longitudinal bridge decks are increasingly utilized across the United States. However, limited research exists to develop bridge railing systems for high-service-level roadways that meet current vehicular impact safety standards. In response to this gap, the United States Department of Agriculture - Forest Service -Forest Products Laboratory (USDA-FS-FPL), in collaboration with the Midwest Roadside Safety Facility (MwRSF), initiated a research program to develop, crash test, and evaluate higher-service-level bridge railings and approach guardrail transitions (AGTs) compliant with the American Association of State Highway and Transportation Officials (AASHTO) Manual for Assessing Safety Hardware (MASH).

This study continued …

Towards Advancing Streamflow And Peak Flow Prediction With Machine Learning: Identifying Infrastructure At Risk, Sudan Pokharel

Dissertations and Doctoral Documents, University of Nebraska-Lincoln, 2023–

Due to climate change and its impact, the need for adaptive strategies for natural disaster mitigation and resource management has never been more urgent. Central to this is water resource management, which is essential for sustainable human activities, ecological balance, and the mitigation of natural hazards like floods. Streamflow is a crucial element of water resource management and plays a vital role in planning and building water infrastructure, implementing emergency response plans, supporting flood mitigation initiatives, and regulating agricultural and industrial use. However, accurate prediction of streamflow still remains a challenge due to the complex non-linear and non-stationary interaction between …

Robot-Integrated 4d Building Information Modeling (4d Bim): Framework For Planning Safe Autonomous Construction Operations In Dynamic Environments, Hafiz Oyedimeji Oyediran

Dissertations and Doctoral Documents, University of Nebraska-Lincoln, 2023–

In the construction industry, the use of autonomous robots is considered a solution to overcome the heavy reliance on human workers to perform repetitive, strenuous, and hazardous tasks. While these robots offer the advantage of autonomous operation, ensuring their safe and efficient integration within construction sites requires precise planning. Such planning must account for the varying project complexities such as scope, site layout, tasks, timelines, existence of human workers, and other spatiotemporal conditions of the construction site. Currently, there are no methods to safely plan autonomous robot operations considering these factors within the overarching construction planning process. Thus, autonomous robots …

The Prototype Of A Fully Automated Pressuremeter For Various Geotechnical Applications, Anuar Akchurin

Theses and Dissertations

The geotechnical engineering field requires high-quality in-situ testing equipment that ensures consistency in the test execution. This research focuses on developing and testing a prototype of a fully automated pressuremeter control unit to allow the industry to obtain reliable and controlled stress-strain data, thereby improving efficiency and reducing testing time.

The objectives of this work are to design and develop a system with the necessary components to perform the pressuremeter test, integrate the testing procedure into the state machine design, enable automated testing, and validate the results by comparing the stress-strain data with that obtained from the existing hand-operated pressuremeter …

A Laboratory Study Of Local Scour And Driftwood Effects At A Type A Piano Key Weir, Manisha Panthi

All Graduate Theses and Dissertations, Fall 2023 to Present

Piano key weirs are a unique weir designed to increase the amount of flow that passes over it via its zig-zag shape (similar to the rectangular shape of keys of a piano). With its relatively small footprint, they are becoming more popular to upgrade existing water management projects and are also being used in new construction works. However, there is little information available regarding how these weirs handle sediment and driftwood. Additional information will help researchers and designers to understand the challenges of upstream sediment buildup, driftwood accumulation, and the effects of floods on downstream scour with viable protection measures. …

Irrigation Performance Connection To Water Quality In Big Creek, Sena Bildim

All Graduate Theses and Dissertations, Fall 2023 to Present

Due to new technologies and improved water management strategies, sprinkler irrigation systems are becoming more common in Utah and nearby areas. These systems are generally thought to be more efficient, but their effects on water quality are not well understood. This study focuses on the Big Creek watershed, which flows into Bear Lake—an area where water quality concerns are increasing.

The purpose of this research was to explore how different irrigation systems—sprinkler and surface—affect both water use and water quality. Field tests were conducted to measure how evenly water was applied and how efficient each system was. Water and soil …

Water Use By Irrigated Turfgrass And Connections To Climate And Biophysical Processes, Karem Meza

All Graduate Theses and Dissertations, Fall 2023 to Present

Urbanization and limited water supply and storage result in imbalanced urban water budgets. Quantification of water use becomes important in urban landscapes because urban turfgrass requires a significant amount of water and competes with other urban requirements. Evapotranspiration (ET) plays a crucial role in determining irrigation needs. Credible measurements and spatial estimates of urban turfgrass ET are needed for urban water management. However, these have not been addressed in urban landscapes in arid and semiarid regions. Despite estimating spatial urban turfgrass ET, turfgrass quality linked to ET has not been widely evaluated. Due to different environmental conditions, the driving forces …

Exploring Variations In High-Resolution Downstream Hydraulic Geometry Of The Logan River, Gabriel V. Benitez

All Graduate Theses and Dissertations, Fall 2023 to Present

Rivers are dynamic systems that change shape due to natural events like floods, landslides, and wildfires, as well as human-made structures like bridges. These changes create unique and complex river patterns. However, measuring these changes accurately is challenging because traditional field surveys are time-consuming and often focus on easily accessible areas, which may not represent the whole river. Thanks to new high-resolution mapping technology and detailed river flow records, we can now see these changes in greater detail than ever before.

In this study, we focused on the Logan River, which flows through a canyon with a mix of rocky …

A Laboratory Study On The Hydraulics Of Stepped Spillways: Effects Of Step Geometry And A Labyrinth Crest, Megh Raj K C

All Graduate Theses and Dissertations, Fall 2023 to Present

Observed trends in extreme storms are affecting the safety of several embankment dams. Spillways are critical for safely conveying excess water in the reservoir over the dam and into the downstream river, yet many dams that were built over 40 years ago have undersized spillways to handle modern flood estimates requiring repairs and upgrades. Consequently, a unique spillway crest, the labyrinth weir, has been used as a cost-effective improvement for numerous projects to enhance discharge capacity of existing weirs. Another cost-effective option for overtopping protection due is to place a less expensive concrete, Roller-Compacted Concrete (RCC), over the dam to …

Investigating Changes In Hydroclimate, Land Cover, And Evapotranspiration Across The Great Salt Lake Basin And Its Major Subbasins, Bhuwan Ghimire

All Graduate Theses and Dissertations, Fall 2023 to Present

The Great Salt Lake (GSL) is a lake of environmental and economic importance for Utah, and in recent years lake levels have declined to critically low levels. The lake level is dependent on the balance between the inflow and outflow. Inflow into the lake is governed primarily by the streamflow originating from the Bear, Weber and Jordan River basins (GSL subbasins), direct precipitation over the lake and groundwater entering into the lake. The GSL is a terminal lake, with outflow via evaporation from the lake.

In this study, we examined hydrologic processes within the river basins that relate to streamflow …

Increasing The Spatial Resolution Of Snow Hydrology Data And Augmenting Existing Hydrology Monitoring Networks Using Low-Cost Snow Sensing Stations, Braedon Dority

All Graduate Theses and Dissertations, Fall 2023 to Present

Snow is a crucial part of the water cycle, especially in mountainous regions where melting snow provides water for millions of people. However, accurately measuring how much water is stored in snow is challenging. Current monitoring networks, such as the snowpack telemetry (SNOTEL) network in the western United States, provide valuable data, but have gaps in coverage and are expensive to operate and expand. This research explores a more affordable way to improve snow measurements by designing and testing low-cost snow sensing stations. These stations use open-source datalogger and software technology along with research-grade sensors to measure important snow variables. …

Surface Vortex Mitigation At Submerged Intakes, Camren Todd

All Graduate Theses and Dissertations, Fall 2023 to Present

Surface vortices at submerged intakes entrain air, convey debris, and reduce efficiency. This research investigates the effect of lid geometry on mitigation of surface vortices at submerged intakes in the context of still reservoirs. Six lid geometries were evaluated: three solid lids of increasing diameter, two lids with perforations, and one lid fitted with a downward curtain. Vortex severity was measured by Alden’s vortex type rating scale, surface-dimple diameter, and qualitative video analysis.

The perforated lid extension and the curtain configurations were most effective at mitigating vortices. The curtain configuration negated all surface swirling by redirecting a portion of the …

Influence Of Terrain Model Resolution On Rockfall Dispersion And Tortuosity Of Rockfall Paths, Lucas Jason Arsenith

Boise State University Theses and Dissertations

The geology of the Snake River Plain region of southwestern Idaho contains terraces formed from downcutting of the Boise River and columnar jointed basalt cliffs from lava flows. Within the city limits of Boise, Idaho, rockfall events originate from these columnar jointed basalt cliffs. Whitney Terrace, a rockfall-prone location in southwestern Boise, was chosen as the study site. Site-specific LiDAR data was used to create a bare earth terrain model, and rockfall boulders were geolocated and measured to be used as inputs into rockfall models. The slope below the cliff face was divided into four distinct slope zones, each with …

Kinetic Growth Rate Analysis Of Coelastrella Sp. In Aquaculture Wastewater., Rob Skarvan

Master of Engineering Theses

The demand for sustainable food and energy production continues to rapidly rise. Utilizing aquaculture wastewater as microalgae growth medium is a potential opportunity for nutrient recycling and industrial symbiosis, but more research is required to understand how best to design and scale-up a dual-purpose facility. This study investigates the growth of Coelastrella sp. in aquaculture wastewater compared to industry-standard growth medium BG-11 and modified tap water as controls. Though cell size and pigment density varied throughout media, aquaculture wastewater performed very comparably to BG-11 as a microalgae culture broth.

The Monod equation can model Coelastrella sp. growth based …

Selecting Green Wall Adoption Best Solutions Using Optimization: Addressing Barriers And Maximizing Benefits, Samar Nadeem

Theses and Dissertations

This research explores the potential of green walls as a sustainable solution to mitigate urban challenges and align with global climate change objectives. Despite their ecological and social benefits, green wall implementation faces significant barriers, hindering their adoption. Consequently, this study aims to develop a comprehensive framework to identify the obstacles, propose feasible solutions, and provide actionable strategies for promoting green walls. This framework incorporates an optimization model specifically designed for government-led solutions, evaluating their feasibility based on administrative feasibility, community acceptance, technical feasibility, industrial acceptance, and long-term adoption potential. By quantifying and prioritizing solutions based on their cost, feasibility, …

Estimation Of Breach Hydrograph Resulting From Dam Embankment Failure Due To Internal Erosion Or Overtopping: Comparison Of Simplified Methods With Real-Case Failure Data And Recommendations, Laurent Del Gatto, Jean-Robert Courivaud

5th International Seminar on Dam Protections Against Overtopping

The opening of a breach in an embankment dam, whether due to overtopping or internal erosion, is a critical failure mode for these structures. Estimating the resulting breach hydrograph is essential for assessing downstream risks. While no universal physical model covers all dam types, empirical formulas are commonly used. EDF analyzed 14 such formulas, comparing them with rupture data from 32 embankment dam failures. The best formulas - Froehlich 1995, Xu & Zhang 2009, and CLF 2020 - yield a “best estimate” for peak flow. However, due to variability, results should be interpreted cautiously. Consider estimating breach characteristics like width …

Breach Modeling Flume Tests, R. M. Monteiro-Alves, R. Moran, M. Á. Toledo, M. Morris, C. Picault, J-R. Courivaud

5th International Seminar on Dam Protections Against Overtopping

From previous flume tests conducted in the framework of the OVERCOME Project, intended to investigate the effect of different soil materials, overflow discharges, and upstream face watertightness on the breaching processes of overflowed levee sections, we determined the need for further investigation on the effect of test repeatability, content of fines and armouring caused by the coarser particles. This document presents the results of this new set of tests which have shown an impact of these variables on the breach macro erosion processes, erosion rates and breach dimensions.

Development Of Low-Carbon Cementitious Composites With Volcanic Ash And Calcium Carbide Residue Using Carbonation Curing, Jad Samir Bawab

Thesis/ Dissertation Defenses

The production and use of cement and concrete is a major contributor to numerous environmental problems, primarily centered around high carbon emissions, extensive resource depletion, and vast waste generation. This thesis aims to develop and characterize low-carbon concrete by using volcanic ash (VA) and calcium carbide residue (CCR) as partial cement substitutes while exposing the cementitious composite to accelerated carbonation curing. The study is a multi-level assessment of the incorporated materials and curing method divided into four phases. The first stage studied and optimized the CCR content and carbonation curing parameters of carbonation-cured concrete. It was revealed that using 5% …

Physically Based Assessment Of Flow Resistance In Stepped Chutes, T. L. Wahl, B. J. Heiner, K. R. Smithgall, C. C. Shupe, J. Falkenstine

5th International Seminar on Dam Protections Against Overtopping

Existing physically based methods for estimating stepped chute friction factors or energy dissipation rates consider relative step height and relative step-tip spacing to be key factors, but do not fully account for chute slope and associated step orientation. For slopes steeper than 45° each step acts as an offset into the flow, while for flatter slopes each step presents an offset away from the flow, but methods that consider only the step-tip spacing do not account for this difference. Furthermore, most experimental studies have been performed in open channel spillway models, where two-phase air-water flow and variable flow depths make …

Ahead Of His Time? A Reanalysis Of The Air-Tunnel Stepped Chute Studies Of Marcos José Tozzi, T. L. Wahl, J. A. Higgs, J. Matos

5th International Seminar on Dam Protections Against Overtopping

Stepped spillways offer energy dissipation advantages and construction efficiencies over smooth spillway chutes. Energy dissipation is typically estimated using empirical relations that depend on chute slope, unit discharge and relative step height. Open-channel tests of model spillways experience self-aerated air-water flow downstream from the aeration inception point, and the presence of air dramatically affects energy dissipation and flow depth, making it difficult to separately determine the effects of step geometry and other basic flow properties. The 1992 doctoral dissertation of Marcos José Tozzi from the Polytechnic School of the University of São Paulo included open channel stepped spillway tests with …

Hydraulic Measurements In A Saf Stilling Basin With A Stepped Chute For Embankment Protection, B. M. Crookston, N. Young

5th International Seminar on Dam Protections Against Overtopping

Stepped chutes have become commonplace in embankment dam rehabilitation projects due to project economy, constructability, and improved chute energy dissipation. Consequently, for applications where a stilling basin is merited the interaction of stepped chutes and stilling basins is of high interest. A commonly used stilling basin type for many smaller embankment dams, the St. Anthony Falls stilling basin (SAF), has no specific hydraulic design guidance for use downstream of a stepped chute. Therefore, this study was conducted at the Utah Water Research Laboratory in a flume with 0.1 m tall steps, a total drop height of 1.8 m, and an …

Assessing A Solution For Ga Work Zone Safety Through Cross Classification, Asiah Lightfoot, Sunanda Dissanayake

Symposium of Student Scholars

Work zone safety is a health risk for drivers and construction workers. In Georgia, work zone crashes have decreased over the past 5 years, but the number of fatalities has still been over 1,000 each of those years. Studies have proven solutions such as lowering the speed limit or relying on current traffic control devices to be ineffective. The risks associated with these crashes must be recognized to improve upon previous solutions or innovate new ones from the results. The objective of this study is to utilize cross classification to identify factors that contribute to work zone crash deaths and …

2d Probabilistic Scour Model For Predicting The Time-Rate Of Scour For Spillways And Overtopping Dams Based On The Erodibility Index Method, M. F. George, G. W. Annandale

5th International Seminar on Dam Protections Against Overtopping

Time-dependent prediction of rock scour for dams and spillways has largely remained elusive given limited available data on rock erosion rate parameters in literature. Recently, a theoretical framework for determining the rate of rock scour was developed by Annandale (2025), enhancing the Erodibility Index Method (EIM). The EIM is the most commonly used and accepted approach for evaluation of scour in rock for dam applications. This theoretical framework has been incorporated into the 2D probabilistic jet impingement scour model (George & Annandale, 2023) so that scour progression due to head-cutting in a spillway channel (lined or unlined) or overtopping onto …

Building Resilience: Strategies For Sustainable Wildfire Management In California, Jaiden Rennie, Pegah Zamani

Symposium of Student Scholars

Wildfires in California are becoming more intense and destructive, threatening communities, ecosystems, and livelihoods. This project explores how resilience and sustainability can work together to reduce wildfire risks and long-term damage. By reviewing research, case studies, and expert insights, it examines what’s driving these fires, climate change, poor land management, and human activity, and looks at solutions that can make a real difference. From community education programs to AI-driven fire detection and smarter policies, the findings highlight practical ways to better prepare for and manage wildfires. The goal is to contribute to a future where communities and the environment are …

Development Of A Microcontroller-Based Intelligent Traffic Light Control System For Vehicular Movement In T-Junctions, Frederick O. Ehiagwina

Tanzania Journal of Engineering and Technology (TJET)

This research is devoted to the issue of regulating traffic congestion in major cities using light-dependent resistors coupled with the PIC16F877A microcontroller. This study proposes an intelligent traffic control system for T-Junctions, utilizing sensing and control to optimize traffic flow through dynamic phase adjustments and congestion reduction, enabled by a microcontroller-based decision-making system. The proposed system reduces traffic congestion, automates control, and enhances safety, minimizing accidents and lowering infrastructure costs. Under simulated environment, it demonstrates an average response time of 50 ms and achieves 99% accuracy in displaying the correct countdown. Finally, the number of state transitions handled per minute …