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On Time-Series Analysis By Structured Matrix Decompositions With Applications To Signal Direction-Of-Arrival Estimation, Georgios Ierotheos Orfanidis

Electronic Theses and Dissertations

Modern autonomous systems operating in highly dynamic, non-stationary environments require reliable inference from short, potentially corrupted time-series measurements, where conventional statistical methods relying on large-sample support and stationarity assumptions become fundamentally inapplicable. This dissertation develops a unified, model-free theoretical framework for time-series analysis, with a particular application to signal Direction-of-Arrival (DoA) estimation, grounded in structured matrix decompositions under both the L2-norm and L1-norm formulations.

We first approach the problem from a conventional viewpoint by carrying out standard matrix analysis directly on Hankel-structured representations of time-series data. In this context, we demonstrate that L1-norm decompositions of Hankel matrices offer strong resistance …

Quantifying Evapotranspiration From The Wetlands In The Peripheral Area Between The Most Downstream Stream Gages And The Open Water Body Of The Great Salt Lake, Motasem S. Abualqumboz, David G. Tarboton

Publications

Study region: The eastern peripheral area between the most downstream stream gages and the open water body of the Great Salt Lake (GSL), located in northern Utah within the semiarid western United States (US). 

Study focus: As GSL levels decline, the eastern peripheral area is expanding, exposing former lakebed, much of which has transitioned into natural and managed wetlands. Evapotranspiration (ET) from these wetlands consumes water that would otherwise reach the open-water lake body, yet these losses remain poorly quantified and directly affect the GSL water balance. This study compares a water-balance-based ET estimate for the wetlands in the peripheral …

Computer Vision And Deep Learning-Based Decision Support System Using Eye Motion Tracking For Nystagmus Detection, Kowshik Balasubramanian

Electronic Theses and Dissertations

This thesis presents the design, implementation, and experimental validation of an artificial intelligence (AI)-driven system for detecting and quantifying nystagmus an involuntary, rhythmic oscillation of the eyes intended as a portable, low-cost complement to conventional Videonystagmography (VNG). The complete pipeline integrates six algorithmic stages: face landmark detection, contrast enhancement, background-aware pixel thresholding, grid-based vertical column filtering, connected-component cluster analysis, and centroid computation, operating in real time on standard smartphone video to extract a sub-pixel normalized iris position time-series without any specialized eye-tracking hardware or infrared illumination. The system supports diagnostic decision-making, highlighting its promise for incorporation into telemedicine settings. The …

External Force Control Of Transitional And Turbulent Flows, Cesar Alberto Leos

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

Turbulence in wall-bounded flows governs momentum transport, drag, and energy efficiency in a wide range of engineering systems, yet its response to external forcing remains incompletely understood across transitional and high Reynolds number regimes. This dissertation investigates an active flow control strategy based on spanwise external forcing and demonstrates how it modifies the dynamics of transitional and turbulent channel flows with the objective of identifying the mechanisms through which forcing alters transition, flow physics, and turbulent drag reduction.

Firstly, direct numerical simulations are performed to examine the subcritical transition under external forcing. The onset and sustenance of turbulence are shown …

2026 - The Thirtieth Annual Symposium Of Student Scholars

Symposium of Student Scholars Program Books

The full program book from the 30th Annual Symposium of Student Scholars, held on April 22-24, 2026. Includes abstracts from the presentations and posters.

Parameter Optimization And Field Application Of Roof Volume Fracturing Using Horizontal Wells For Coalbed Methane Extraction From Broken-Soft Coal Seams, Zhang Qingli, Sun Siqing, Li Haozhe, Wu Xiaoxuan, Yang Fan, Zheng Yuqi, Li Wenbo

Coal Geology & Exploration

Objective and Method To achieve rapid coalbed methane (CBM) extraction from broken-soft coal seams using surface horizontal wells, this study proposed a volume fracturing technology for coal seam roof using horizontal wells. Focusing coal seam 4-1 in a mining area, this study established a numerical model using finite element analysis (FEA) software Abaqus Using this model, the impacts of in-situ stress on the cross-layer propagation characteristics of multiple fractures were investigated. Through true triaxial hydraulic fracturing experiments, the multi-fracture propagation patterns under varying injection rates of fracturing fluids, perforation cluster numbers, and cluster spacings were analyzed. Using 3D fracturing design …

Joint Inversion For Heat Transfer Parameters Of Porous Media With Geothermal-Seepage Coupling Based On A Physics-Informed Neural Network, Zhang Xiao, Yang Duoxing, Cong Lin, Cheng Yimei, Zhang Lianzhong

Coal Geology & Exploration

Background The thermal diffusivity and vertical seepage velocity of porous media are critical to characterizing the mechanisms underlying subsurface heat transfer. These two parameters are typically determined through inversion using temperature data since they are difficult to measure directly. Fiber-optic distributed temperature sensing (FO-DTS) can yield high-resolution, continuous temperature profiles, providing data for parameter identification. However, conventional numerical inversion suffers from limitations such as mesh dependency and sensitivity to initial values when used to process continuous monitoring data. Methods This study proposed a joint geothermal parameter inversion method that integrates FO-DTS data with a physics-informed neural network (PINN). Specifically, the …

Advanced Studies In Characterization Of Pyrolysis Products From Live Vegetation, Mahsa Alizadeh

Theses and Dissertations

Fire is a naturally occurring element in many ecosystems which can have both positive and negative effects. However, in recent years the frequency of the fires and the area they affect has increased. The rapid spread of wildland fires coupled with the limited resources available to forest services to manage wildland fires highlights the urgency for accurate prediction of fire spread. Fire prediction models enable the fire management services to predict the spread of fire and prioritize firefighting efforts more effectively. Understanding reactions and mechanisms occurring during wildland fires improves the fire prediction models. During wildland fires, the biomass covering …

Energetic Characterization Of 3-D Printed Acrylonitrile Butadiene Styrene Fuels For Hybrid Rocket Propulsion Applications, Stephen A. Whitmore, Ryan J. Thibaudeau, Ava T. Wilkey

Mechanical and Aerospace Engineering Faculty Publications

Hybrid rocket technologies are gaining recognition as eco-friendly alternatives to traditional propulsion systems. Utah State University’s Propulsion Research Laboratory has developed a High-Performance Green Hybrid Propulsion (HPGHP) technology, leveraging 3D-printed ABS fuel for reliable, low-energy ignition. Among tested materials, only ABS shows suitable electrical-breakdown properties for arc ignition. Unfortunately, due to the proprietary formulations in commercial ABS blends, and its limited use as a rocket-propellant, related composition and combustion data are limited. This study uses spectroscopic evaluation and bomb calorimetry to estimate material compositions, enthalpies of formation, and combustion energies for multiple commercially available 3-D print feed stock ABS types, …

Transitional And Turbulent Dynamics In Viscoelastic Wall-Bounded Flows, Alexia Martinez Ibarra

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

The addition of small amounts of long-chain polymers to a turbulent flow has been reported to modify the flow phenomena when compared to Newtonian flows, resulting in a significant skin-friction reduction. Although polymer-induced drag reduction has been extensively studied through both experimental and numerical studies, a unified and predictive understanding of the phenomenon is still lacking. This dissertation focuses on better understanding of this phenomenon, particularly on the transitional regime, which remains largely unexplored but is of utmost importance for both practical and fundamental purposes.

Firstly, direct numerical simulations are performed to study the effect of polymers on the laminar-turbulent …

Investigating The Cost And Efficiency Of Two Chemical Pathways To Produce The Plant-Based Coagulants, Taylor Nixon

Honors Theses

Plant-based coagulants are promising sustainable alternatives for water treatment due to their biodegradability, low toxicity, and reduced risk of secondary pollution. Unlike conventional inorganic coagulants, they generate less sludge and avoid secondary contamination in the environment. This project examines two chemical modification strategies for producing cationic cellulose coagulants. The first involves direct amination of cellulose using CHPTAC, while the second employs periodate-oxidized dialdehyde cellulose, which enables reductive amination through reactive aldehyde groups. These approaches are expected to yield materials with differing charges, surface functionalities, and structural properties that may influence coagulation performance. The study evaluates the technical and economic feasibility …

Mild Thermal Treatment Of Lithium-Ion Batteries To Optimize Black Mass Production, Brooke Lillie

Theses and Dissertations

This thesis explains the design of equipment and the experimental procedure for thermal treatment of lithium-ion batteries for the purpose of low-cost materials recycling. Conditions used were between 150 ℃ and 425 ℃, involving different atmospheric conditions and treatment durations. The battery samples were processed through a sieve shaker device. Mass loss during the heat treatment, and separation of the battery through sieving was used to analyze the effect of the treatments on separability of black mass from the batteries. Additionally, internal battery temperature was measured and compared to real average furnace temperature to monitor thermal runaway. Testing showed minimal …

Modelling Method Of Unmanned Vehicle Dynamics Based On Neural Network, Jun Wang, Min Liu, Xiaochuan Zhang, Yishan Ding, Juhui Feng, Ye Zhuang

Journal of System Simulation

Abstract: To address the challenges of high data acquisition costs of test data on dynamic characteristics between tires and soft terrain and low speed of numerical calculation for unmanned vehicles in complex terrestrial environments, a modeling method of unmanned vehicle dynamics based on a neural network was proposed. Tire-terrain contact dynamics models were built by using discrete element method (DEM) simulations for tire-terrain contact and experimental data, thereby creating a dataset of tire contact forces for various tire materials in terrestrial environments. The neural network was applied to regressively learn the dataset, and a nonlinear neural network tire model was …

Techno-Enviro-Economic Analysis Of Precipitated Calcium Carbonate Production From Carbon Dioxide In Cement Industry Flue Gas And Calcium Hydroxide, Natalia Debora Panggabean, Widodo Wahyu Purwanto

Journal of Materials Exploration and Findings

CCUS is a technological solution to reduce emissions from the cement industry, which is the second largest CO2-intensive industry. This study aims to analyze technical, economic, and environmental performance of Precipitated Calcium Carbonate (PCC) synthesis in cement industry flue gas. The process simulation includes the CO2 capture system from cement plant, CO2 captured used as feedstock for PCC synthesis process through its reaction with calcium hydroxide. The simulation was carried out using ASPEN Plus software. Technical analysis was performed to determine the CO2 capture efficiency and PCC synthesis efficiency. Economic analysis was conducted to calculate CO2 capture cost and production …

Feasibility Analysis Of Thermal Oxidizer To Determine Remaining Life Using Fitness- For-Service Level 3 Method, Yudhi Yudistirawan, Donanta Dhaneswara, Wahyuaji Narottama Putra, Gama Widyaputra, Dewi Kurnia Suci, Agung Putra Mahardhika

Journal of Materials Exploration and Findings

An aged thermal oxidizer (TOX) in the oil and gas industry necessitates a comprehensive evaluation to ensure its continued safe operation. This study presents a Remaining Life Assessment (RLA) and a Fitness for Service (FFS) evaluation for the four main components of the TOX, in accordance with API 510, API 579/ASME FFS-1, and ASME BPVC Section VIII Div-1 standards. The investigation includes the determination of maximum stress and maximum temperature required to assess the operational viability of the reactor. The four components are radiant, convection, transition, and stack sections—were modeled using the finite element method (FEM). Following the geometric modeling, …

Silicon Dioxide Multimode Interferometer Spectrometers, James Harkness

Theses and Dissertations

Multi-mode interferometer (MMI) spectrometers are a type of reconstructive micro-spectrometer based on imaging light propagation patterns in MMI waveguides. This dissertation describes how the MMI spectrometer was implemented for the first time using a silicon dioxide core. This approach showed a 6 dB improvement in SNR over SU-8 core devices. To implement the silicon dioxide MMI spectrometer, a fabrication technique for selectively roughening the surface of the waveguide needed to be developed. SU-8, a photosensitive polymer, was etched with oxygen plasma to create grass-like nanostructures. SU-8 grass can then be used as a transfer mask to plasma etch a surface. …

Stack-Based Exploit Development Techniques In Mips Architectures, Justin Applegate

Theses and Dissertations

Memory corruption vulnerabilities in binary executables represent a serious threat to software security, particularly in embedded and IoT (Internet of Things) devices that commonly use the MIPS architecture. While exploit development techniques for x86 are well-documented in academic literature, little systematic work exists on how those techniques translate to other architectures such as MIPS. This research addresses that gap by evaluating thirteen stack-based exploit development techniques and subtechniques, originally designed in the context of the x86 architecture, for their applicability to MIPS architectures. For each technique, vulnerable C code was written and compiled into both x86 and a set of …

Design And Modeling Of A Piezoelectric Bimorph Energy Harvester For Automotive Structural Vibrations, Ali Abu Shawish

Thesis/ Dissertation Defenses

The focus of this thesis is on the design and modelling piezoelectric bimorph energy harvesters for vehicular utilization, particularly on harvesting energy from local structural vibrations of automotive components. The vibrations resulted from road–tire interaction and drivetrain dynamics offer the potential for harnessing electrical energy for low power electronic systems when coupled with low damping resonance harvesting devices. The main purpose of this thesis is to evaluate the potential of a piezoelectric bimorph cantilever tuned to 100–300 Hz local automotive structural vibrations for electrical energy harvesting, and to analyze its actual performance under realistic excitation conditions. The harvester's dynamic response, …

Modeling Flood-Induced Cascading Disruptions In The Indian Electronics Supply Chain Using Influence Network Analysis, Surendra Orupalli, Hiroki Sayama

Northeast Journal of Complex Systems (NEJCS)

This study investigates flood induced disruptions in the Indian electronics supply chain using influence network analysis. Monsoon floods are recurring hazards that significantly impact economic activities, logistics, and industrial productivity. This study integrates district-level rainfall data (2020 to 2025) with supply chain network models to quantify cascading failures. The methodology applies rainfall thresholds (≥ 300 mm/month) to identify flood-prone districts and constructs a stochastic influence matrix representing inter-firm dependencies. Flood propagation dynamics are modeled iteratively with a propagation coefficient (α = 0.6) and convergence threshold (ε = 10⁻⁴). The resulting disruption profiles are mapped onto company-level revenues calibrated to India-specific …

Three Degree Of Freedom Wave Energy Converter Design For Resonant Motion, Greg Ballen, David G. Wilson, Rush Robinett, Shangyan Zou, Wayne Weaver

Michigan Tech Publications

As multiple-degree-of-freedom (3-DOF) wave energy converters (WECs) have demonstrated the ability to produce more power than single-degree-of-freedom devices, the challenge of designing buoys for efficient energy harvesting has increased in complexity. In this paper, a cylindrical WEC is designed to naturally resonate in surge, pitch, and heave modes at a specific target frequency of 0.2 Hz. By utilizing a penalty-based optimization method to balance buoyancy requirements with natural resonance, the design achieves minimal control force input, thereby reducing fluctuations in energy output and local energy storage requirements. The performance is evaluated under irregular sea states using a Bretschneider spectrum. Results …

Toward Human-Like Robot Behavior In Co-Manipulation: Learning From Human Dyad Performance, Adam Kenneth Jackson

Theses and Dissertations

Co-manipulation requires two or more agents to coordinate through a shared object while exchanging information through motion and force. Although this capability is routine for humans, robotic systems still struggle to participate in such interaction naturally and effectively. This thesis addresses that gap by studying human co-manipulation behavior, developing methods to quantify performance, collecting a leader-follower dataset that isolates haptic communication, and training data-driven controllers from human demonstrations. First, cumulative and real-time metrics were developed to quantify human dyad performance. In particular, the behavioral modes "quickly" and "smoothly" were formulated as measurable performance objectives using completion time and squared jerk. …

Hypertext Transfer Protocol Fingerprinting: Techniques For Attacker-In-The-Middle Proxy Detection, Evasion, And Counter-Evasion, Jensen George Wood

Theses and Dissertations

Attacker-in-the-middle (AitM) phishing toolkits have emerged as a critical threat to enterprise and individual security by enabling adversaries to bypass multi-factor authentication (MFA) and compromise cloud-based accounts at scale. Traditional detection techniques--such as IP blocklists or content-based detection methods--are often ineffective against these increasingly sophisticated attacks. We propose a novel method that detects malicious proxies by identifying artifacts they introduce into HTTP request headers. To evaluate our approach, we systematically analyze traffic passed through several open-source AitM toolkits and proxies, identifying distinct modifications to header structures and content, then formalize these features as YARA rules for automated use. To validate …

Predictive Analytics In Oncology And Ophthalmology: Machine Learning Applications For Diabetic Retinopathy And Breast Cancer, Ali Abidalkareem

Electronic Theses and Dissertations

The convergence of artificial intelligence and healthcare represents one of the most transformative developments in modern medicine, with deep learning technologies emerging as powerful tools for addressing complex diagnostic challenges. This dissertation develops and validates machine learning frameworks that address critical challenges in medical diagnosis through innovative approaches to data augmentation, feature learning, and classification, focusing on two fundamental problems: Diabetic Retinopathy (DR) severity classification using multi-model convolutional neural networks (CNNs), and breast cancer stage identification using microRNA (miRNA) gene expression biomarkers. For diabetic retinopathy classification, this work proposes an ensemble deep learning framework that integrates Diffusion-based data augmentation for …

Evaluating Ai-Driven Sustainable Neuro-Urbanism Through A Human-Centered Framework: The Case Of Ras Elbar City, Egypt, Esraa Elazab, Ahmed Eltawil

Mansoura Engineering Journal

This study applies and evaluates a previously developed human-centered framework for AI-driven sustainable neuro-urbanism through a case study of Ras Elbar City, Egypt. Building on earlier conceptual research that integrated artificial intelligence (AI), neuroscience-informed design, and sustainability principles, this paper seeks to test the framework’s practical relevance in the context of a developing coastal city. Using qualitative evaluation methods, including field observation and spatial assessment, the research examines twelve key urban design elements such as green spaces, mobility networks, lighting, and soundscapes. Each element is analyzed across three dimensions: neuro-urbanism goals, AI integration, and sustainability outcomes. The findings show that …

Application Of Fidic Epc/Turnkey Contract Under The Egyptian Public Works Contracts Law, Ahmed Alhady Dr., Mahmoud Mahmoud Ahmed Eng., Ahmed Elhakeem Prof., Mohamed Ibrahim Dr.

Civil Engineering

This study focuses on the application of FIDIC Conditions of Contract for EPC Turnkey Projects—Silver Book 1999, (FIDIC (EPC&T)), when governed by the Egyptian Law of Contracts concluded by public bodies No. 182 of 2018 (ELC) due to the conflicts that may arise from such application. Hence, this study identifies specific FIDIC (EPC&T) 1999 clauses that have the potential for conflicts with ELC, shows the similarities and disparities between these clauses and the relevant ELC articles, and provides recommendations to ensure the successful application of FIDIC (EPC&T) 1999 under ELC. This was achieved through a multistep research methodology in which …

Security Risks Of Ai-Generated Code In Software Development, Maame Agyekum

Cybersecurity Undergraduate Research Showcase

Artificial Intelligence(AI) has recently forced change globally, public Institutions and as well as national security. Advancement in machine learning, mixed datasets have enabled significantly powerful systems while being capable of operating at a large scale. As innovation and technological advancement increases at rapid pace, issues like a regulation gap where scientific development far exceeds the government’s ability to regulate and establish an effective oversight. As a result, Artificial Intelligence has been controlled by private companies, leading to an industry where speed and profit often outweigh safety and ethical responsibility.

Growth Potential Of Materials For Decarbonization: Insights From The Cement Industry Value Chain, Noha Mostafa

Mechanical Engineering

To meet the Paris Agreement objectives and limit global warming to 1.5˚C compared to preindustrial levels, it is estimated that the built sector must cut its total emissions by 50% before the year 2030 and fully decarbonize it by 2050. The built environment is estimated to be responsible for 40% of global energy and emissions. These global carbon emissions include both operational carbon—the day-to-day carbon emissions generated through the operation and maintenance of buildings—and embodied carbon. With its recorded high emissions, cement manufacturing is a key area of interest for the decarbonization efforts. To meet the increasing demand for sustainably …

Systematic Design And Optimization Of Porous Bone Plates Using Taguchi Method And Finite Element Analysis, Aliaa A. Farraj, Tawakol A. Enab, Hanan M. Amer, Mostafa A. Elbahloul

Mansoura Engineering Journal

Solid bone fixation plates, although clinically effective, often induce stress shielding and impair periosteal blood flow due to their mismatch in stiffness with cortical bone. To overcome these limitations, this study proposes lattice-engineered porous bone plates designed to balance mechanical integrity and biological compatibility. A systematic parametric investigation was conducted by varying three design variables: crystal structure type (diamond, fluorite, and gyroid), porosity levels (50%, 70%, and 90%), and structure layout. Three-dimensional models were developed using nTopology, and finite element analysis (FEA) was performed under a static compressive load to evaluate stress distribution. A Taguchi L9 orthogonal array was employed …

Biomass Demineralization: A Critical Need For Future Biorefineries, Leoncio Santiago-Martínez, Styliani Avraamidou, Alejandro Ayala-Cortés, Ruth Azike, Santanu Bakshi, Chumki Banik, Ezra Bar Ziv, Fei Long, Rebecca Ong, Et Al.

Michigan Tech Publications

Biomass contains up to 14 essential elements that serve as nutrients for plant growth and development, including photosynthesis and enzyme functionalities. These elements in different chemical forms (e.g., minerals) constitute the inorganic fraction of biomass and can cause operational issues in thermal and biochemical biomass conversion technologies. In biomass gasification and pyrolysis processes, for instance, inorganics can cause fouling, tar formation, and corrosion. In catalytic and biochemical processes, inorganics can poison catalysts, alter biochemical pathways, and modify product yields and selectivity. This review provides an overview of the inorganic content in biomass feedstocks, the critical role inorganics play in plant …

Analysis Of The Effects Of Magnetic Field, Heat Transfer, And Thermal Radiation On Blood Flow Through Bifurcated Artery To Enhance Tumor Treatments, Abdullahi Isah, Dauda Gulibur Yakubu, Ali Musa

Tanzania Journal of Science

The work presents the effects of some pertinent parameters on blood flow through bifurcated artery to enhance tumor treatments. Combining appropriately the basic equations, together with the fractionalized Maxwell fluid model allow us to determine the velocity, temperature and concentration of blood flow through bifurcated artery. The study adopted the Atangana-Baleanu fractional time derivative on fluid model to describe the non-Newtonian behavior of blood flow. The numerical simulations were performed using the combined Laplace transform and the method of undetermined coefficients and the results obtained with the aid of Mathcad software were simulated and presented graphically. From the graphical results, …