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The Processing Of Emotional Prosody And Semantics In Native And Non-Native Chinese Speakers, Cheng Xiao Oct 2025

The Processing Of Emotional Prosody And Semantics In Native And Non-Native Chinese Speakers, Cheng Xiao

Theses and Dissertations

Emotional information in spoken language is conveyed through both semantic and prosodic cues. While listeners interpret the meaning of utterances (what is said), they also detect the speaker’s emotional prosody (how it is said). For non-native speakers, processing these two types of information simultaneously can be challenging, particularly in a tonal language such as Mandarin Chinese, where the same acoustic feature (i.e., pitch) encodes both lexical semantics and emotional prosody. This dissertation reports a series of behavioral and fMRI experiments investigating how native and non-native Chinese speakers perceive and process emotional prosody and semantics in words and sentences. Behaviorally, results …


Improving District Targeted Support For Schools With Low Student Achievement By Implementing Assistance Relationships With School Leaders, Mary Ashley Gaskins Oct 2025

Improving District Targeted Support For Schools With Low Student Achievement By Implementing Assistance Relationships With School Leaders, Mary Ashley Gaskins

Theses and Dissertations

Riverbend School District faced a challenge: the lack of a formalized structure for providing schools with targeted support that meets their unique needs and increases student achievement. This study explored how the district-level instructional team could customize support to improve English Language Arts and Math performance at schools with low student achievement. The theory of improvement posited that district instructional leaders engaging in assistance relationships – through modeling instructional leadership and providing conceptual and practical tools – would enhance school leaders' capacity, ultimately improving teaching and learning. A key action of the improvement team was the creation and implementation of …


Developing A Comprehensive Schoolwide Discipline Plan In Title 1 Southern Schools, Rose Clark Kebe Oct 2025

Developing A Comprehensive Schoolwide Discipline Plan In Title 1 Southern Schools, Rose Clark Kebe

Theses and Dissertations

This qualitative case study explored how teachers in Title I schools across the southern United States perceived and experienced school discipline practices. The study addressed the problem of inconsistent implementation of restorative and preventive frameworks, which has contributed to inequitable outcomes, teacher frustration, and lost instructional time. Although initiatives such as Positive Behavioral Interventions and Supports (PBIS) are mandated across many districts, inconsistent use and limited fidelity have restricted their effectiveness in improving equitable discipline and school climate.

The purpose of the study was to examine teacher perspectives to inform the development of a culturally responsive, schoolwide behavioral system grounded …


Anthropomorphism In Language And Thought: The Effect Of Agentive Linguistic Framing On Readers’ Perceptions Of Ai Animacy, Dawson Petersen Oct 2025

Anthropomorphism In Language And Thought: The Effect Of Agentive Linguistic Framing On Readers’ Perceptions Of Ai Animacy, Dawson Petersen

Theses and Dissertations

Over the past decade, deep learning AI systems have gone from academic obscurity to near cultural centrality in the developed world. As these technologies become increasingly integrated into daily life, there is growing cause for concern about AI anthropomorphism—i.e., the perception of AIs as more human than they really are. Despite the potential risks, AI developers continue to market their technologies using agentive language that seems to be designed to encourage anthropomorphism. The current dissertation utilizes behavioral and eye-tracking methods to examine the relationship between agentive linguistic framing and AI anthropomorphism in both controlled judgments and automatic inferences. The results …


Behind The Gens: A Bioarchaeological Study Of Kinship Structure And Social Change In Iron Age Latium, Italy, Andrea Noemí Acosta Caballero Oct 2025

Behind The Gens: A Bioarchaeological Study Of Kinship Structure And Social Change In Iron Age Latium, Italy, Andrea Noemí Acosta Caballero

Theses and Dissertations

The cemetery of Osteria dell’Osa is the only completely published Iron Age cemetery from Latium. Its research legacy continues as dietary, mobility, and biological affinity patterns were reconstructed through carbon, nitrogen, oxygen, and strontium isotope analyses and biodistance analysis using bone and dental samples for this dissertation project. The main hypotheses tested are:

a) The diet of people buried at Osteria dell’Osa during the Iron Age likely consisted of mostly grains like wheat and barley, which may yield low carbon isotope signatures;

b) The protein consumption of the diet of people at Osteria dell’Osa was mainly composed of terrestrial protein …


Strategies For Developing Mathematical Identities In Middle School Students, Margaret M. Stevens Oct 2025

Strategies For Developing Mathematical Identities In Middle School Students, Margaret M. Stevens

Theses and Dissertations

This concurrent mixed-methods action research study investigated the impact of mathematical discourse intervention on seventh-grade students’ mathematical identities and understanding. Twenty students participated in a four-week intervention implementing Smith and Stein’s (2018) five practices plus one framework.

Quantitative results showed curriculum-based assessments improved significantly (p < .001, d = 1.64). State mathematics assessment revealed minimal change in mean scores. The Mathematical Identity Questionnaire revealed positive shifts across all five constructs, with largest gains in Mathematical Initiative (+0.40) and Problem-Solving Persistence (+0.30). Qualitative analysis using Bingham’s (2023) five-phase process revealed three themes: Mathematical Voice Development, Identity Transformation Through Competence Building, and Communal Validation. Social Cognitive Theory and Culturally Relevant Pedagogy integration showed how discourse interventions addressed both individual self-efficacy and systemic inequities. Findings suggest intensive discourse intervention can initiate positive changes in mathematical identity and understanding for struggling students. Implications include restructuring mathematics instruction to prioritize student discourse and voice, creating more equitable learning environments.


A Comparative Analysis Of Two Symphonies By Robert Volkmann: Symphony No. 1 In D Minor, Op. 44, And Symphony No. 2 In B-Flat Major, Op. 53, Baha Lee Oct 2025

A Comparative Analysis Of Two Symphonies By Robert Volkmann: Symphony No. 1 In D Minor, Op. 44, And Symphony No. 2 In B-Flat Major, Op. 53, Baha Lee

Theses and Dissertations

The 19th-century music scene boasts countless names, but some, like Robert Volkmann (1815–1883), have faded from the spotlight despite his prolific output as a composer, conductor, and educator. Volkmann’s music remains largely unknown and unperformed, waiting to be rediscovered. This lack of recognition provides a compelling opportunity to appreciate a talented composer and rekindle interest in his music. While scholarly inquiries into Volkmann are rare, delving into his major orchestral works, particularly his two symphonies, offers not only an understanding of his artistry but also a chance to revive interest in his captivating music.

Robert Volkmann composed only two symphonies …


Food Insecurity And Social Connection Of Nicaraguan Refugees And Asylum Seekers In Costa Rica: A Qualitative Study, Keren Herran Oct 2025

Food Insecurity And Social Connection Of Nicaraguan Refugees And Asylum Seekers In Costa Rica: A Qualitative Study, Keren Herran

Theses and Dissertations

Background

Given the physical and mental health consequences of food insecurity, solutions should be evidence-based and seek to prioritize vulnerable populations. This qualitative study adds to limited literature on how refugees and asylum seekers use their social connections to mitigate food insecurity by investigating how Nicaraguan refugees and asylum seekers in Costa Rica foster social connections and use these connections to acquire and manage food.

Methods

In fall 2024, 35 in-depth semi-structured interviews were conducted in San José, Costa Rica. Participants were recruited through six migrant-serving nonprofit organizations. For study inclusion, participants had to: 1) be 18 or older; 2) …


Erosion Of Bermuda Grass Covered Soils, Oru-Ntui Johnwatters Nkiri Oct 2025

Erosion Of Bermuda Grass Covered Soils, Oru-Ntui Johnwatters Nkiri

Theses and Dissertations

Earthen embankments are the most common type of embankment due to the relatively low cost, simplicity, and material availability. However, they are also the most prone to erosion related failure, typically due to overtopping and piping. Research has been conducted to identify ways to control soil erosion and protect earthen embankments with different approaches such as addition of chemicals and biopolymer to the soil, installation of protective layering (geotextiles, concrete), increased soil compaction, and use of vegetation. This thesis considers the use of Bermuda Grass to increase resistance to erosion and protect embankments from failure during overtopping. Grass coverage and …


Gut Microbiome Dynamics In Heart Failure And The Therapeutic Potential Of Nmeg-Cgrp, Kamryn Michael Gleason Oct 2025

Gut Microbiome Dynamics In Heart Failure And The Therapeutic Potential Of Nmeg-Cgrp, Kamryn Michael Gleason

Theses and Dissertations

Heart failure (HF) is increasingly recognized as a multisystem disease often linked to gut dysbiosis; however, its specific effects on gut microbial composition remain poorly understood. This study examined long-term changes in the gut microbiome in a murine HF model induced by transverse aortic constriction (TAC) and evaluated the effects of NMEG-CGRP. TAC mimics pressure overload-induced cardiac dysfunction, replicating key features of HF. CGRP, a neuropeptide with vasodilatory and cardioprotective effects, shows potential as a therapy for HF but is limited by rapid degradation. A stabilized analog, NMEG-CGRP, was used to assess its impact on cardiac and gastrointestinal health. Mice …


Application Of Machine Learning For Vascular System Analysis, Alireza Bagheri Rajeoni Oct 2025

Application Of Machine Learning For Vascular System Analysis, Alireza Bagheri Rajeoni

Theses and Dissertations

The analysis of vascular structures is critical for diagnosing, monitoring, and treating vascular diseases such as aneurysms, stenosis, and vascular calcification. Traditional methods often rely on manual interpretation of imaging data, which is time-consuming, subjective, and not scalable. This work explores the application of advanced machine learning techniques to automate and enhance vascular system analysis. Our contributions include achieving state-of-the-art accuracy in vascular segmentation, developing a machine learning pipeline to automatically quantify vascular calcification in peripheral arterial disease, and designing a multi-stage machine learning system for abdominal aortic aneurysm analysis that identifies aneurysm boundaries and estimates aneurysm volume in a …


Performance Limiting Factors For Silicon Anodes In Lithium-Ion Batteries, Najmaddin Bashirzada Oct 2025

Performance Limiting Factors For Silicon Anodes In Lithium-Ion Batteries, Najmaddin Bashirzada

Theses and Dissertations

The rising global demand for high-performance and sustainable energy storage solutions has placed lithium-ion batteries (LIBs) at the forefront of technological progress. However, the energy density limits of traditional graphite anodes require the investigation of alternative materials. Silicon (Si), with its high theoretical capacity, is a promising anode material. Still, its practical use faces major challenges such as volumetric expansion, unstable solid electrolyte interphase (SEI) formation, and low conductivity. This thesis examines the electrochemical behavior and limitations of Si-based electrodes using coin cells and ex-situ three-electrode cells. A comparison of electrochemical testing methods – i.e., Galvanostatic Intermittent Titration Technique (GITT) …


Downwind-Upwind Flux Path Analysis Method For Model Reduction Performance Evaluations, Christian Robert Smith Oct 2025

Downwind-Upwind Flux Path Analysis Method For Model Reduction Performance Evaluations, Christian Robert Smith

Theses and Dissertations

Large, complex chemical kinetic models have long since been limited by the computational cost it takes to evaluate said model. Over time many reduction methods have been developed to combat this computational cost. However, very little has been done towards evaluating the limitations of reductions as a way of understanding the original model’s characteristics. This paper aimed to use a path flux analysis-based reduction algorithm to rapidly develop multiple reduced mechanisms for a 96 species FFCM-2 methane chemical kinetic model as well as an 858 species n-Dodecane chemical kinetic model. The goal of formulating these reduced mechanisms was to identify …


Towards Accurate First-Principles Modeling In Heterogenous Catalysis: Ethane Dehydrogenation And Hydrogenolysis Over Pt Catalysts, Mubarak Ayo Bello Oct 2025

Towards Accurate First-Principles Modeling In Heterogenous Catalysis: Ethane Dehydrogenation And Hydrogenolysis Over Pt Catalysts, Mubarak Ayo Bello

Theses and Dissertations

First-principles modeling has become central to heterogeneous catalysis research, offering mechanistic insight and guiding catalyst design, yet conventional approaches often struggle to accurately describe complex catalytic systems due to methodological uncertainties, simplified assumptions, and the structural diversity of nanoparticle catalysts. This dissertation addresses these challenges using ethane dehydrogenation (EDH) and hydrogenolysis (EH) over platinum catalysts as model systems. The first study benchmarks density functional theory (DFT) functionals against the random phase approximation (RPA) for the EDH network on Pt(111), identifying cost-effective functionals and demonstrating the efficiency of BEEF-vdW ensembles for capturing functional uncertainty. The second study (addressed in prior work) …


Identifying And Understanding The Barriers To Sexual Health Information Seeking Experienced By Young Adults (Ages 18-26) Using Social Media, Alexander Nicolas Vera Oct 2025

Identifying And Understanding The Barriers To Sexual Health Information Seeking Experienced By Young Adults (Ages 18-26) Using Social Media, Alexander Nicolas Vera

Theses and Dissertations

This dissertation uses a qualitative, constructionist approach to examine the sociotechnical and cultural dynamics that shape digital sexual health-seeking practices of young adults. Guided by information practices and affordance theory, the research draws on semi-structured interviews and digital walkthroughs with 20 young adults (ages 18–26) from a convenience sample of young adults residing in South Carolina. Participants described how they use platforms like TikTok, Instagram, and Reddit not only to locate information but to assess its trustworthiness, inclusivity, and personal relevance in real time. Through in-depth accounts and screen-based demonstrations via digital walkthroughs, the study examines how participants engage in …


Multiphysics Modeling, Analysis, And Design Of Ceramic Hollow Fiber Membranes For Oxygen Separation, Hamed Abdolahimansoorkhani Oct 2025

Multiphysics Modeling, Analysis, And Design Of Ceramic Hollow Fiber Membranes For Oxygen Separation, Hamed Abdolahimansoorkhani

Theses and Dissertations

Oxygen plays a central role in numerous industrial processes. Several technologies have been reported for producing oxygen from air. Among them, oxygen transport membrane (OTM) technology—based on mixed-conducting, gas-tight ceramic membranes—has attracted significant attention due to its high oxygen selectivity, relatively low capital and operating costs, and versatility for both ex-situ and in-situ applications. Mathematical modeling of OTMs offers a powerful tool to investigate internal multi-physics transport phenomena, providing deeper insight into fundamental mechanisms while serving as a cost-effective approach for optimizing membrane stack designs.

After a comprehensive introduction, in the first part of this dissertation (chapter 2), a comprehensive …


A Building Block Approach To Certification By Analysis Applied To A Ditching Analysis, Preliminary Studies, Sean Taylor Oct 2025

A Building Block Approach To Certification By Analysis Applied To A Ditching Analysis, Preliminary Studies, Sean Taylor

Theses and Dissertations

Extended Twin-Engine Operations (ETOPS) certification ensures safe trans-oceanic operation of transport category aircraft. A critical aspect of ETOPS certification is compliance with ditching regulations. The importance of ditching analysis has grown significantly and come under greater scrutiny because of the ‘Miracle on the Hudson’ incident. For transport category aircraft certified under 14 CFR 25 regulations, compliance with ditching requirements, rests on two major components. First, demonstrating acceptable aircraft dynamic behavior during the ditching event and second, ensuring the airframe can withstand the loads generated because of water impact.

Historically, original equipment manufacturers (OEMs) relied on comparisons to existing aircraft with …


Implicit Neural Representation For Image Reconstruction, Canyu Zhang Oct 2025

Implicit Neural Representation For Image Reconstruction, Canyu Zhang

Theses and Dissertations

Image reconstruction seeks to restore corrupted images and recover visual content that has been lost or degraded. Such degradation may result from low resolution, occlusion, masking, or shadow interference. This problem has become an increasingly significant research topic, as visual information plays a central role in almost every aspect of modern life. Neural network based approaches have recently emerged as highly effective solutions for this task. In particular, convolutional neural networks and transformer based architectures have demonstrated remarkable success in producing visually convincing reconstructions. However, these models remain constrained in several important ways, one of the most critical being that …


Recognizing The Unexpected: Deep Learning Across Complex Environments, Ge Song Oct 2025

Recognizing The Unexpected: Deep Learning Across Complex Environments, Ge Song

Theses and Dissertations

Ensuring the security, trustworthiness, and operational integrity of modern autonomous and cyber-physical systems presents a critical challenge. While widely utilized in various engineering applications, such as intelligent transportation and industrial manufacturing, these systems require robust monitoring frameworks to identify unexpected anomalies in real-time, thereby maintaining operational safety and efficiency. This dissertation develops advanced deep learning methodologies for anomaly detection and health monitoring, with a particular emphasis on semisupervised reconstruction-based approaches that identify anomalies in complex environments using models trained only with normal operational patterns.

Building on this theme, the first study focuses on analyzing pedestrian behavior and detecting anomalies at …


Development Of A Strategy To Neutralize Ccl8 Activity And Ablate Ccl8 Cellular Targets, Bernardo Chavez Oct 2025

Development Of A Strategy To Neutralize Ccl8 Activity And Ablate Ccl8 Cellular Targets, Bernardo Chavez

Theses and Dissertations

The chemokine CCL8 (monocyte chemoattractant protein-2) is a versatile signaling molecule involved in tumor progression, immune cell recruitment, and therapeutic resistance. Through activation of receptors including CCR1, CCR2B, and CCR5, CCL8 promotes leukocyte trafficking, epithelial–mesenchymal transition, and the establishment of immunosuppressive tumor microenvironments. In breast cancer and inflammatory diseases, elevated CCL8 levels correlate with poor clinical outcomes, making it a promising therapeutic target.

A strategy was developed to block CCL8 activity and selectively ablate CCL8 receptor expressing cells. A neutralizing monoclonal antibody, 1G3E5, was identified from a panel of murine candidates based on high affinity CCL8 binding. Sequencing revealed two …


Parental Attitudes And Expectations Regarding Piano Study For Their Children With Autism Spectrum Disorder, Lin Zhong Oct 2025

Parental Attitudes And Expectations Regarding Piano Study For Their Children With Autism Spectrum Disorder, Lin Zhong

Theses and Dissertations

This study investigates parental attitudes and expectations regarding piano study for children with Autism Spectrum Disorder. Although music has been recognized for its therapeutic and educational benefits among individuals with ASD, research examining these outcomes from the perspective of parents has been limited. This study focuses on in-depth interviews with nine parents of children with ASD enrolled in the Carolina LifeSong Initiative, a specialized piano program serving students with diverse developmental disorders.

The interviews explored parents’ motivations for initiating piano study, expectations for both musical and non-musical outcomes, and observations of their children’s growth and challenges through music. Parents reported …


Spectral Modeling Of Electromagnetic Radiation From Power Converters, Regan A. Varner Oct 2025

Spectral Modeling Of Electromagnetic Radiation From Power Converters, Regan A. Varner

Theses and Dissertations

Switching power converters are increasingly utilized in contemporary electronics. They are becoming more compact and operate at higher frequencies, which contributes to radiated electromagnetic interference (EMI). This EMI is important to quantify for electromagnetic compatibility of the converters with other nearby systems. In this thesis, analytical models have been developed for both ideal and non-ideal switching waveforms, employing piecewise functions to describe time-domain waveforms, with their corresponding frequency spectra derived and compared to empirical spectra. The results demonstrate that the comparisons with measured frequency data exhibit agreement with the analytical models up to approximately 25 MHz. Additionally, our analysis indicates …


Calculating Surface Current Velocities From Video Generated From A Near Forward-Facing Camera, Colby James Weeks Oct 2025

Calculating Surface Current Velocities From Video Generated From A Near Forward-Facing Camera, Colby James Weeks

Theses and Dissertations

This work presents a camera system for estimating surface currents. A combined camera and IMU system provide high resolution images and high precision orientation information, respectively. This eliminates the need for leveling and enables forward looking operation. The hardware stack includes a Lucid Vision Triton TRT162S monochrome camera, an SBG Ellipse D with dual antenna GNSS for precise pose, and an Nvidia Jetson Orin for acquisition and processing. The Ellipse D provides a hardware trigger at 10 Hz to time stamp each frame and to synchronize images with inertial measurements.

A camera calibration step estimates the intrinsic camera parameters and …


Towards Robust Bmocz Schemes For Non-Coherent Wireless Communication, Anthony Joseph Perre Oct 2025

Towards Robust Bmocz Schemes For Non-Coherent Wireless Communication, Anthony Joseph Perre

Theses and Dissertations

Non-coherent communication has emerged as a promising approach to address several challenges at the physical layer. A particular scheme called binary modulation on conjugate-reciprocal zeros (BMOCZ) uses the zeros (i.e, roots) of a polynomial to convey information bits. In this thesis, we strive to improve the reliability of BMOCZ in various scenarios. In particular, we utilize machine learning (ML) methods to determine the parameters for BMOCZ and improve upon the decoding performance. Moreover, we introduce a smooshed BMOCZ variant to combat typical impairments encountered within wireless communications, including timing offsets (TOs) for noncoherent orthogonal frequency division multiplexing (OFDM). Through numerical …


The Role Of Fibroblast Activation Protein On Left Ventricular Growth And Extracellular Matrix Remodeling As A Function Of Age And Pressure Overload, Amelia Marie Churillo Oct 2025

The Role Of Fibroblast Activation Protein On Left Ventricular Growth And Extracellular Matrix Remodeling As A Function Of Age And Pressure Overload, Amelia Marie Churillo

Theses and Dissertations

Fibroblast activation protein (FAP) is abundantly expressed in cancer associated fibroblasts and contributes to extracellular matrix (ECM) remodeling. Recent studies using imaging techniques have identified increased levels of FAP in the left ventricle (LV) of patients identified as at risk for developing heart failure. However, the role of FAP in regulated LV myocardial structure and function remains unclear. This project tested two hypotheses: First, genetic ablation of FAP would modify LV structure and function and be more pronounced with aging. Second, genetic ablation of FAP would modify LV structure and function with LV pressure overload (LVPO) accompanied by ECM remodeling.


Multi-Layer Decision Making For Long-Term Autonomous Mission Based On Dual Process Theory, Shruti Jadhav Oct 2025

Multi-Layer Decision Making For Long-Term Autonomous Mission Based On Dual Process Theory, Shruti Jadhav

Theses and Dissertations

Unmanned aerial vehicles (UAVs) are increasingly used in precision agriculture, where extended autonomous operation is required for monitoring, intervention, and field management. However, achieving long-term autonomy remains challenging due to battery constraints, environmental uncertainty, and the need to balance exploration with event-driven tasks. To address these challenges, a multi-layer decision-making framework inspired by Dual Process Theory (DPT) is developed. The framework combines reactive return-tobase strategies, exploratory navigation, and directional bias from prior missions, with a conflict-monitoring mechanism that adapts system behavior based on real-time conditions. The approach is implemented in a simulated agricultural grid environment, demonstrating improved adaptability and coverage …


Reduced Order Simulator Of A Nuclear Thermal Propulsion System, Jackson Taylor Zazzaro Oct 2025

Reduced Order Simulator Of A Nuclear Thermal Propulsion System, Jackson Taylor Zazzaro

Theses and Dissertations

This thesis presents the development of a reduced-order simulator for a nuclear thermal propulsion (NTP) system, designed to capture the key thermo-fluid and performance characteristics of such systems while maintaining computational efficiency. The primary objective of this work is to develop and demonstrate a modular simulation framework capable of modeling the coupled physics of an NTP reactor, nozzle, and orbital transfer system. The simulator integrates a reduced-order thermal-fluid model of the reactor, a simplified nozzle model, and an orbital transfer model, providing a comprehensive yet computationally efficient representation of the propulsion process. By employing reduced-order modeling techniques, the simulator achieves …


A Qualitative Study Of Middle School Teachers’ Experiences Integrating Computer Coding Into Mathematics Classrooms, George William Austin Iii Oct 2025

A Qualitative Study Of Middle School Teachers’ Experiences Integrating Computer Coding Into Mathematics Classrooms, George William Austin Iii

Theses and Dissertations

As computers become more accessible in schools nationwide, teachers are embracing them to impact achievement positively (Brudno, 2013; Cetin, 2016). As a result, computer coding instruction has gained attention as a strategy for providing students with skills that will serve them both pre and post-graduation (Burke & Kafai, 2013; Yadav et al., 2016; Ng, 2017). Computer coding is the process of providing instructions for a computer to follow. In 2017, the South Carolina State Board of Education approved Computer Science and Digital Literacy standards for all K-8 public schools in the state of South Carolina (South Carolina Department of Education, …


Rate-Dependent Interlaminar Shear Characterization In Solid-State Extruded Ultrahigh Molecular Weight Polyethylene Film Composites, Frank David Thomas Jr. Oct 2025

Rate-Dependent Interlaminar Shear Characterization In Solid-State Extruded Ultrahigh Molecular Weight Polyethylene Film Composites, Frank David Thomas Jr.

Theses and Dissertations

Ultrahigh Molecular Weight Polyethylene (UHMWPE) cross-ply [0o/90o] thin film composites are emerging as an effective material for impact applications due to their high axial strength-to-weight ratio and favorable delamination properties. Mode-II interlaminar shear (ILS) fracture-driven delamination has been shown to be a significant energy absorption mechanism. Therefore, accurately characterizing ILS behavior as a function of strain rate in these composites is essential to inform computational models. Since these composites are significantly thinner and weaker in both interlaminar shear and transverse tension than traditional carbon fiber epoxy composites, standard ILS Mode II test methods/specimens such as end-notched flexure (ENF) are expected …


Enhancing Two-Phase Heat Spreading: Development And Performance Evaluation Of Hermetically Sealed Hybrid Heat Sinks, Walker Ryan Champion Oct 2025

Enhancing Two-Phase Heat Spreading: Development And Performance Evaluation Of Hermetically Sealed Hybrid Heat Sinks, Walker Ryan Champion

Theses and Dissertations

Modern, high-performance technology presents challenges for thermal management based on power density. To cool heat fluxes to this degree, conventional liquid-cooled heat sinks are utilized because air cooling becomes insufficient (>100 𝑊/𝑐𝑚2 ). This study introduces a hybrid heat sink that integrates liquid cooling with a dropwise-enhanced vapor chamber, contains a hermetic seal, and achieves high thermal performance with low energy consumption. The temperature hotspots, thermal resistances, gravitational/pin effects, temperature uniformity, and coefficient of performance were investigated. Experimental results demonstrate a high cooling capacity of 600 W over a 6.25 𝑐𝑚2 heating area with a low cooling …