Digital Commons Network^™

Fuel Injection For Hypersonic Air-Breathing Propulsion Systems, Justin Sprunger

Graduate Thesis and Dissertation post-2024

Hypersonic air-breathing propulsion systems face unique challenges related to fuel injection due to the supersonic flow in the combustor. For example, residence times within supersonic combustors are often orders of magnitude shorter than the timescales required for quality delivery of fuel. Additionally, because of the high incoming momentum of the free stream, fuel penetration is difficult to achieve without intrusive fueling structures. Intrusive fueling structures, however, are not desired as they induce high efficiency losses and require advanced cooling systems or thermal protection solutions. Therefore, an understanding of the trajectory of fuel injected from the sidewall of a combustor is …

Autonomous Navigation And Real-Time 3d Reconstruction Of Interior Spaces Using A Quadruped Robot, Steve Wilhelm

Graduate Thesis and Dissertation post-2024

This thesis develops and evaluates a ROS2-based application that enables the quadruped robot Unitree Go2 to simultaneously perform autonomous navigation, real-time mapping, and 3D reconstruction in indoor environments using Simultaneous Localization and Mapping (SLAM). The robot system, equipped with onboard sensors, aims to generate high-resolution point clouds that provide detailed 3D scans. The assessment focuses on the platform’s practical feasibility, operational reliability, and accuracy. The hardware setup combines the Unitree Go2 robot with its built-in sensors, a high-resolution 3D LiDAR, and an RGB-D camera. Software components include ROS2, the Unitree SDK, a navigation framework, and SLAM approaches. The application was …

Towards Robust Deep Learning: Label Noise Modeling, Algorithms, And Applications, Diego Fernando Linares Gonzalez

Graduate Thesis and Dissertation post-2024

This thesis investigates robust and hybrid deep learning with emphasis on improving accuracy and generalization in challenging real-world settings, including learning under noisy supervision and applications to complex scientific data.

In the first part, we address instance-dependent label noise by using a tensor factorization–based methodology that models the noise transition process as an instance-dependent decomposition. We also utilize low-rank block-term structures to capture class-specific and instance-specific correlations. Moreover, we include a robust loss function and rank regularization to achieve stable optimization during model training. We validated this with experiments on benchmark datasets, like Fashion-MNIST, CIFAR-10, and CIFAR-10N, demonstrating higher accuracy …

Reconfigurable Antenna Arrays For Mm-Wave Directional Software-Defined Radio Communications, Ectis Velazquez Jr

Graduate Thesis and Dissertation post-2024

This dissertation explores design challenges and promising solutions for mm-Wave directional software-defined radio (DSDR) reconfigurable antenna arrays. Current state-of-the-art solutions for DSDR antenna arrays at mm-Wave frequencies are typically limited to one beam, which does not take advantage of the directivity and spatial reusability of mm-Wave bands. Additionally, mm-Wave phased array antennas typically incur large amounts of loss from both commercial and state-of-the-art beam steering methods. In this dissertation, both challenges are addressed and so- lutions are proposed through several novel antenna array designs. The first challenge, designing an array for mm-Wave DSDR communications is achieved through a switched-beam array, …

A Framework For Machine Learning Surrogate Modeling In Physics-Based Reacting Flow Simulations, Jose O. Bobren-Diaz

Graduate Thesis and Dissertation post-2024

The design of next-generation combustion systems relies on computer simulations that capture the multidimensional and multiscale physics of turbulent reacting flows. These simulations are computationally intensive, requiring trade-offs to produce results within allowable time and cost constraints. These trade-offs often consist of general assumptions and modeling simplifications that approximate complex physical phenomena. Consequently, these models can limit both the accuracy and the regime of applicability to real systems since these approximations are often heuristic and inconsistent with the governing physics. Moreover, in today’s rapid design-to-prototype development phase, making timely and informed design decisions is important. This requires fast and reliable …

Advancing Heterogeneous Collaborative Perception For Autonomous Vehicles, Babak Ebrahimi Soorchaei

Graduate Thesis and Dissertation post-2024

Recent advances in computational and communication technologies have enabled deep neural networks (DNNs) and high‐speed vehicular wireless links, paving the way for cooperative perception and cognition in autonomous systems. By exchanging complementary observations, these methods overcome inherent sensor limitations, such as occlusions and restricted range, and thereby improve the detection of partially hidden targets. However, real‐world deployments face challenges from noisy measurements (e.g., GPS inaccuracies) and heterogeneous perception stacks: vehicles often rely heavily on visual detectors, yet there is no standardization ensuring uniform object‐detector architectures across a fleet.

In this dissertation, we first explore the design of a lightweight detector …

Communication-Aware Trajectory Prediction And Tracking For Connected And Autonomous Vehicles, Arash Raftari

Graduate Thesis and Dissertation post-2024

This dissertation presents a unified framework for communication-aware trajectory prediction and vehicle state tracking in connected and autonomous vehicle (CAV) systems. Unlike most deep learning–based forecasting models that assume full observability of surrounding agents, the proposed approach explicitly accounts for limited communication range, packet loss, and bandwidth constraints that characterize real vehicular networks.

A model-based, error-driven information-passing policy is introduced to extend situational awareness beyond one hop. Rather than relaying messages based on distance or freshness, each vehicle evaluates the utility of received content in reducing system-wide position tracking error (PTE). Using compact Gaussian Mixture Model (GMM) representations of motion …

A Multivariable Feedback Approach To Individual Pitch Control For Fatigue Load Reduction In Wind Turbines, Kazi Ishtiak Mohsin Mr.

Graduate Thesis and Dissertation post-2024

This dissertation investigates advanced control strategies to improve performance and reduce fatigue loads in both land-based and floating offshore wind turbines. The proposed approaches target fatigue load mitigation at critical component frequencies while ensuring rotor speed regulation and efficient power generation. The control strategies are implemented and validated using both our in-house modeling and simulation platform, CRAFTS (Control Oriented Reconfigurable Acausal Floating Turbine Simulator), and the industry-standard OpenFAST model.

For land-based turbines, torque actuation and collective blade pitch control are incorporated into a nonlinear controller for rotor speed regulation and power generation. To address fatigue load reduction, individual pitch control …

Attention-Based 3d-Convolutional Neural Network Model For Mechanical Property Predictions Using, Daniel E. Traczyk

Graduate Thesis and Dissertation post-2024

Additive manufacturing (AM), while commonly used for rapid prototyping and creating components with complex geometries, has not been widely adopted for critical applications across the aerospace, automotive, defense, energy, and medical industries. This is, in part, due to the challenges of controlling flaws and uncertainty in the mechanical behavior of additively manufactured components. In recent years, there has been an increase in research aimed at predicting the final mechanical properties of additively manufactured components during the printing process. To address these issues, a 3D-CNN model was trained using low-cost in situ visible-light camera data, anomaly classifications, and the chosen process …

Load Modulated Balanced Amplifier (Lmba) With Antenna-Vswr Resilience For Energy- And Spectrum-Efficient Communications, Jiachen Guo

Graduate Thesis and Dissertation post-2024

The rapid evolution of 5G and forthcoming 6G networks demands higher data rates and lower latency within increasingly congested spectrum resources. Advanced modulation schemes such as high-order quadrature amplitude modulation (QAM) and orthogonal frequency-division multiplexing (OFDM) have been widely adopted to improve spectral efficiency; however, these techniques substantially increase the peak-to-average-power ratio (PAPR) of transmitted signals. To enable power amplifiers (PAs) to operate efficiently under this conditions, load-modulated balanced amplifiers (LMBAs) have been developed as an effective solution while inherently supporting broadband operation. On the other hand, the deployment of massive multiple-input multiple-output (MIMO) technology and highly integrated active-antenna systems …

Flywheel Technology: The Reliability Of Functional And Systemic Perturbations In A Crossover Design, Trevor J. Dufner

Graduate Thesis and Dissertation post-2024

The purpose of this dissertation series was to evaluate the reliability, validity, and applicability of the Desmotec D.EVO isoinertial flywheel device (D.EVO) for both isometric and dynamic squat assessments. Study one sought to establish the validity of the D.EVO for assessing squat maximal voluntary isometric contraction (FMVIC) versus a traditional squat maximal voluntary isometric contraction (TMVIC), determine the test-retest reliability of force and power outputs during FMVIC and flywheel squat protocols (FSPs), and explore relationships between these outputs and broad jump (BJ) and vertical jump (VJ) performance. We also identified the number of familiarization sessions needed for reliable data collection. …

Survivors Speak: Social Media's Influence On The Troubled Teen Industry, Jessica Hoffman

Graduate Thesis and Dissertation post-2024

This study focused on a three-year span of Twitter/X public tweets and discussions shared on the topic, The Troubled Teen Industry (TTI). Using the social listening tool Sprinklr, 7,743 public tweets were gathered on the matter and dissected to understand the influence the online conversation had on real-world changes in the industry. Narrowing down the initial 7,743 tweets to 2,447 applicable messages, this research analyzed the conversation surrounding the Troubled Teen Industry from the point of view of industry survivors and the role Paris Hilton and other influencers had on bringing the conversation to the digital space. The tweets meeting …

Insights Into Iapodian Lifeways: Phytolith And Starch Grain Analysis Of Animal And Human Dental Calculus From Croatia, Angelinne Moreno

Graduate Thesis and Dissertation post-2024

The Piplica hillfort is located near the village of Lovinac within the Lika region of Croatia. The Bronze Age is a pivotal period in Europe that encompasses changes in landscapes, social structures, and famously includes vast production of metals. The Bronze Age in Lika is characterized by changes in social, political, and economic lifeways; denser populations; expanded trade networks; and advancements in agriculture, husbandry, and metal-working. However, little is known about the Iapodes people, who inhabited the Lika region during the Late Bronze Age, and how they interacted with their environment.

The Iapodes were only known from classical Greek written …

Manipulated Workplace Hazing And Attributions, Cole B. Treadaway

Graduate Thesis and Dissertation post-2024

Workplace hazing has scarcely been researched, and when it has, the results have not always aligned. This study seeks to remedy the discrepant findings by examining the importance of hazing severity, as prior operationalizations of hazing severity utilizing the most frequently used and validated measure of workplace hazing do not adequately measure severity, as well as by introducing attribution theory to offer a potential explanation as to why some people respond favorably and others unfavorably to being hazed. This study utilized an experimental 2x2 factorial design with an added control group to examine whether the severity of the hazing and …

Better Models For Mosquito Control: Impacts On Nontarget Insects And Joint Species Distributions Of Mosquitoes, Jacob D. Hart

Graduate Thesis and Dissertation post-2024

Since its inception, mosquito control has been vital for limiting the spread of vector-borne pathogens. Modern control efforts balance the protection of public health and the prevention of environmental harm. We addressed this from two directions: the study of mosquito adulticide effects on nontarget insects, and fine scale distribution modeling of mosquitoes to better target control efforts. We first investigated the effects of ultra-low volume (ULV) pyrethroid applications on nontarget insects in Central Florida and found no statistically clear evidence of reduction in abundance or diversity. We reported a slight and statistically unclear reduction of night-flying Lepidoptera, and effective reduction …

Examining The Impact Of The Menstrual Cycle On Neutrophil Function: Immune Response, Il-8 Sensitivity, And Exercise Perception In Resistance Trained Eumenorrheic Women, Jessica M. Moon

Graduate Thesis and Dissertation post-2024

The purpose of this dissertation series was to examine the effect of the menstrual cycle on neutrophil chemotaxis and adhesion profiles, as well as general immunological, functional, and perceptual measures of recovery following resistance exercise in trained women. Study one explored the impact of the early follicular (EFP), late follicular (LFP), and mid-luteal (MLP) phases on neutrophil recruitment and adhesion receptor expression, markers of muscle damage and inflammation, and functional recovery following resistance exercise. Results indicated that menstrual phase did not have a significant impact on immunological recovery or functional recovery. However, main effects of menstrual phase were revealed in …

Bridging Physiology, Data Science, And Genomics To Illuminate Photosynthetic Variation In Sunflower, Rebekah E. Davis

Graduate Thesis and Dissertation post-2024

Photosynthesis is a critical metabolic process in plants involving ‘light reactions’ that capture solar energy to produce ATP and NADPH, and ‘dark reactions’ where these molecules power the enzyme Rubisco to synthesize sugars in the Calvin-Benson cycle. These processes serve as the primary energy source for plant growth and reproduction, displaying significant variation across species and environments. In Helianthus, distinct differences in photosynthetic traits are observed between annual and perennial species. Notably, carboxylation rates, photon capture, and maximum photosynthetic rates show strong phylogenetic signal (Pagel’s λ = 0.99) and are significantly higher in annuals. Photosynthesis is modeled here as a …

Becoming Black In A Divided Diaspora: Identity, Human Security, And The Intra-Group Dynamics Of African Americans And African Immigrants, Pleasant O. Ogedengbe

Graduate Thesis and Dissertation post-2024

This dissertation examines the formation of a shared Black identity among Native Black/African Americans and African immigrants in the United States through an expanded intersectional framework that integrates Social Identity Theory (SIT), Intergroup Contact Theory, and Secondary Marginalization Theory, all under the broader lens of human security. Human security is broadly defined as the protection of individuals from critical threats to their dignity, survival, and livelihood. It is deeply implicated in the experiences of Black communities confronting systemic racism and social exclusion. This study conceptualizes shared identity as a socio-psychological construct and a protective mechanism that enhances group-level resilience and …

Enhancing Social Participation: The Role Of Communication Accommodations On Young Children With Ccn, Carli C. Brent

Graduate Thesis and Dissertation post-2024

BACKGROUND: Children with complex communication needs (CCN) have difficulty using and/or understanding speech to communicate, thus facing barriers for successful social participation in family-leisure activities due to limited access to communication supports in these environments. Social participation includes an individual’s active involvement in activities that consist of a social element to produce opportunities for meaningful interactions with others. Children with CCN benefit from communication supports, like Augmentative and Alternative Communication (AAC) devices. AAC supports children with CCN to effectively communicate with themselves, others, and their environment. While communication supports have been recently implemented into private and public spaces, the …

Skeletal Embodiment Of Structural Violence: Testing Application Of The Weathering Hypothesis In Analyses Of Identified Sex, Jasper K. Shaw

Graduate Thesis and Dissertation post-2024

Structural violence refers to the experiences of inequality faced by marginalized sex, gender, race, and socioeconomic groups. Unequal access to healthcare, housing, and education can cause poor health that may affect how a decedent is analyzed by forensic anthropologists. This research hypothesizes that, due to gender- and sex-based marginalization, females will display greater rates of stress and correlated accelerated aging (i.e., weathering), than males. Computed tomography scans from 100 males and 99 females aged 20-69 years old and white and middle class, were sampled from the New Mexico Decedent Image Database (NMDID). Stress was assessed via cranial porosities, antemortem tooth …

The Effects Of Resistance Training Volume On Muscle Quality Among Older Adults, Kevan Knowles

Graduate Thesis and Dissertation post-2024

BACKGROUND: Age-related declines in muscle strength are more closely linked to deteriorations in muscle quality than muscle mass. Echo intensity (EI) measured by B-mode ultrasonography is a common non-invasive marker of intramuscular adiposity and fibrous tissue. Although high-intensity resistance training is effective, the added value of higher training volumes on muscle quality and strength in older adults remains unclear. PURPOSE: This study aimed to compare the effects of different resistance training volumes on various measures of muscle quality, size, and strength among older adults. METHODS: Twenty-five older adults were randomized to either moderate volume (2 sets per exercise) or high …

Change Point Monitoring In High-Dimensional Factor Models, Mahdi Mirhosseini

Graduate Thesis and Dissertation post-2024

This dissertation presents the Factor-Augmented Detection (FAD) algorithm, a robust methodological framework for online change point detection in high-dimensional data streams, grounded in classical factor model analysis. To tackle the challenges of monitoring large-scale datasets, the FAD algorithm decomposes data into a parsimonious set of common factors and sparsely changing idiosyncratic residuals, facilitating independent, targeted analysis of low-dimensional factor dynamics and sparse high- dimensional residual evolution.

Following decomposition, structural changes in the factor components are identified using established multivariate sequential monitoring techniques, specifically the Multivariate Cumulative Sum (mCUSUM) and Multivariate Exponentially Weighted Moving Average (mEWMA) procedures. Simultaneously, sparse alterations in …

Boba Tea Shops And Identity: Exploration Of Boba Shops Among College Students In Greater Orlando, Naydelin Karime Trejo Vega

Graduate Thesis and Dissertation post-2024

This thesis explores the cultural and social significance of boba tea shops among college students aged 18 to 26 in Greater Orlando. Although many people view boba tea as a trendy drink, this study treats it as a meaningful part of some students’ daily lives, identity formation, and sense of belonging. Through a multi-method approach that includes participant observation, surveys, and semi-structured interviews, I examine what motivates college students to purchase boba tea and how boba shops impact their identity and sense of belonging. I conducted fieldwork at three different boba tea shops in Greater Orlando—two franchises and one locally …

Standby To Standby: How Time Weaponization And Social Currency Impact Identity Within The Veteran Community Upon Discharge., Nichole Ann Carminati

Graduate Thesis and Dissertation post-2024

This research project analyzed the first year of transition from active duty to civilian life by conducting 22 in- person interviews from veteran participants who served in the Global War on Terror post 9/11 and were discharged between 2001 and 2022. The purpose of this research was to identify key areas of vulnerability when evaluating veterans’ transition from military identity to civilian life. Global War on Terror Veterans are at an increased risk of difficulty transitioning to civilian life due to contributing factors of multiple redeployments, stigma over receiving medical and mental health care, and knowledge gaps in obtaining benefits …

Everglades Restoration: Interdisciplinary Analysis And Pluralist Approaches, Sarah Swiersz

Graduate Thesis and Dissertation post-2024

This study uses interdisciplinary methods to analyze ecological restoration of the Florida Everglades (Everglades Restoration). Everglades Restoration is considered one of the largest ecosystem restoration projects in the world, relying on complex intergovernmental and sociopolitical relationships. Framing Everglades Restoration as a quintessential “wicked problem”, a problem that is inherently complex and unsolvable, provides grounds for interdisciplinary analysis. This study analyzes two epistemological approaches to Everglades Restoration: Western-scientific knowledge, the epistemological foundation of Everglades Restoration, and Indigenous Traditional Ecological Knowledge, which challenges the foundations of Everglades Restoration. Interdisciplinary analysis within a decolonial framework identifies limits to integration of knowledge, a core …

The Southern Closet: A Survey Of Queer Community And Protest Methods Against Heteronormativity In Greater Orlando., Edward J. Lay

Graduate Thesis and Dissertation post-2024

In the United States, there have been efforts by the dominant socioeconomic class in Western countries, such as the United States, to regulate gender conformity and heteronormativity in schools, jobs, family structures, and public policy. Florida is no stranger to these efforts of regulation and has had a turbulent history with the LGBTQIA community, enough so that it has occasionally caught the public eye throughout the years. Exploring the actions and effects of the Johns Committee in the 1950s and 1960s, as well as the protests of Anita Bryant in Miami in the 1970s as they challenged equal rights ordinances, …

Effects Of Cerium Concentration And Scattering Centers On The Performance Of Gagg Transparent Ceramic Scintillators, William M. Bowman

Graduate Thesis and Dissertation post-2024

Cerium-doped Gadolinium Aluminum Gallium Garnet (Ce:GAGG) is a rugged scintillator material renowned for its high light output, fast luminescence decay, good stopping power, and energy resolution, making it an ideal candidate for gamma radiation detection. Its optically isotropic crystalline structure enables the fabrication of transparent optical ceramics, effectively addressing certain limitations associated with single-crystal growth. However, the production of highly transparent ceramics often involves costly processing methods with low overall yield. Reactive sintering offers a more economical alternative, but as with other processing techniques, the elimination of scattering centers—such as porosity and secondary phases—remains a significant challenge. These defects hinder …

Characterization, Imaging, And Modeling Of Thermal Dynamics And Failure Mechanisms Of Quantum Cascade Lasers, Alejandro M. Villalobos Meza

Graduate Thesis and Dissertation post-2024

As advancements in Quantum Cascade Laser (QCL) technology continue to push the upper limits of continuous-wave performance, effective thermal management remains at the forefront of design considerations. The compact and highly tunable active region that has made QCL technology so attractive also imposes challenges to heat dissipation during continuous wave operation. To address this ongoing challenge, this work demonstrates a set of characterization and modeling techniques which can be used to interrogate different aspects of the thermal and structural properties of QCLs. Emphasis is placed on a suite of electron microscopy techniques and their role in providing a window into …

Holographic Optical Elements For Complex Beam Transformations, Shaghayegh Yaraghi

Graduate Thesis and Dissertation post-2024

In this thesis, we explore the design, fabrication, and application of volume holographic phase elements in photo-thermo-refractive (PTR) glass for two key purposes: expanding the eye-box in augmented reality (AR) displays and controlling optical angular momentum (OAM) modes in laser cavities.

Encoding complex phase structures in PTR glass enables efficient beam shaping, multiplexing, and wavefront engineering, offering strong potential in AR displays, optical communications, and structured light. Holographic optical elements (HOEs) recorded in PTR glass exhibit high diffraction efficiency (over 99%), thermal stability, and chemical durability. Combined with low absorption and scattering in the visible and near-IR, these features make …

Three-Section Multi Quantum Well Mode-Locked Laser For Optical Comb Generation And Space Applicationsical Comb Generation And Space Applications, Di Huang

Graduate Thesis and Dissertation post-2024

This dissertation presents the design, fabrication, and characterization of three-section AlGaInAs/InP multi-quantum-well mode-locked laser diodes (MLLDs) operating near 1.55 µm for optical frequency-comb generation and control in space communication systems. The devices integrate gain, saturable-absorber, and modulation sections, enabling both passive and hybrid mode-locking with precise tunability through independent bias control. Under hybrid mode-locking, the MLLD achieved 1.32 ps pulses with a 5.87 nm optical bandwidth and a 35 dB improvement in RF side-mode suppression compared with passive operation, demonstrating enhanced timing stability and reduced phase noise. Fixed-point analysis established a framework for evaluating dispersion and frequency drift, while the …