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Uav-Based Quantification Of Dynamic Lahar Channel Morphology At Volcán De Fuego, Guatemala, Jerry C. Mock, Jeffrey B. Johnson, Armando Pineda, Gustavo Bejar, Amilcar Roca

Geosciences Faculty Publications and Presentations

This study quantified erosional and depositional processes for secondary lahars in Las Lajas drainage at Volcán de Fuego, Guatemala, during the rainy season from May to October 2021. Abundant pyroclastic material from ongoing eruptive activity is remobilized seasonally during heavy precipitation, which can impact infrastructure and populations living near Fuego. Our region of focus was in an agricultural zone 6 to 10 km from the summit, surveyed with an unoccupied aerial vehicle (UAV) quadcopter at monthly intervals. Imagery was processed into overlapping time-lapse structure from motion digital elevation models (DEMs). DEMs were differenced to find volumetric changes as a function …

Impact Of Clay Contamination On Rutting Performance Of Asphalt Mixes, Sharmila Afsha

Open Access Theses & Dissertations

Sustainability of asphalt mixtures can be improved by using natural sands. They can enhance workability and lower the amounts required for asphalt binder and manufactured fine aggregate of mixes. However, one of the primary concerns with incorporating natural sands in a mixture is clay contamination. Harmful clays are chemically active particles that swell when exposed to moisture and reduce the bond between aggregate and asphalt binder. As a result, this study explores the effect of clay contamination on the rutting and moisture susceptibility of asphalt mixes. Twenty-one clay combinations of material passing the 0.075 mm (#200) sieve were selected utilizing …

Examining The Association Between Emotional Intelligence, Meaning In Life, Stress, And Burnout Among Preâ??Medical Students In The United States, Nayla Paulina Paulina Bejarano Chacon

Open Access Theses & Dissertations

Background and significance: The Association of American Medical Colleges (AAMC) has estimated that by 2034 there will be a physician shortage of around 124,000 physicians. With burnout being one of the main drivers, it is crucial to assess it. Burnout is characterized by high levels of emotional exhaustion and cynicism and low levels of academic efficacy.There has been substantial research on burnout among healthcare providers across different levels of training; however, few studies have examined burnout among undergraduate students who wish to pursue a graduate degree in healthcare. Given the shortage of healthcare providers in the United States, it is …

Inkjet-Printed Electrochemical Sensors For Lead Detection, Annatoma Arif

Open Access Theses & Dissertations

This PhD dissertation research has developed a simple, miniaturized, sensitive, selective, reproducible, and disposable 3D (inkjet printed – additive manufacturing technology) gold (Au) plated electrochemical sensor (ECS) on shape memory polymer (SMP) for aqueous lead detection. This technology has shown promising performance in the application of electrochemical sensing (lead (II) detection) due to increased effective electrode surface area (7.25 mm^2 ± 0.15 mm^2) despite miniaturizing lateral surface area (4.19 mm^2). The design, fabrication processes, optimization including bismuth functionalization, evaluation, uncertainty analysis, and cost analysis of the novel SMP based inkjet printed Au plated sensor have been delineated in this manuscript …

Geometrical And Surface Texture Characterization For Laser Powder Bed Fusion Process, Jesus Alfredo Rivas

Open Access Theses & Dissertations

Laser powder bed fusion (LPBF) is one of the most widely used additive manufacturing (AM) methods for metal parts. Geometrical tolerances required for industry applications are determined by geometrical measuring methods and process capability calculations. However, geometry characterization presents challenges for LPBF because measuring uncertainty values are not defined and the standardized measurement framework Geometric Tolerancing and Dimension (GD&T) is not fully adopted.

Measurement uncertainty is influenced by this process's high surface roughness (10 µm < Ra ⩽ 80 µm). As an example, when using multiple probing points or scanning pathways on a LPBF surface with the most accurate (+/- 0.004 mm) and traceable measurement method, the coordinate measuring machine (CMM), the results can vary by up to 0.050 mm to 0.070 mm. This measurement uncertainty leads to an imprecise benchmark reference for comparison with optical or X-ray computed tomography (XCT). These measurement variations also make it difficult to accurately characterize parts for automotive, aerospace, medical and other high-tech industries, such as a turbine blade geometry used in aircraft engines with a blade height tolerance of +/- 0.15 mm, which required a measurement uncertainty less than 30% of the tolerances. Mechanical properties such as tensile testing assessments useful in comparisons of materials, alloy development, quality control, and design under certain circumstances are also affected by this imprecise geometry characterization. Overestimating the diameter of the ASTM E8 sample by 0.100 mm can make up to a difference in stress results of 7%.

This research aimed to evaluate various measurement approaches (contact and non-contact) for surface texture and geometrical size dimension characterization and provide information regarding measurement uncertainty …

Interdisciplinary Approach To Understanding Stakeholder Reasoning And Decision-Making For Water, Katalina Salas

Open Access Theses & Dissertations

On a global scale, humanity is compelled to address complex or â??wickedâ?? resource-related issues in the face of accelerating environmental change. In our work, we use the term wicked problem to refer to an issue that has multiple potential solutions and involves various stakeholders. The paths to reach resource sustainability under environmental uncertainty are difficult to identify, plausible outcomes remain uncertain, and tradeoffs required by any path chosen are challenging to understand. Environmental sustainability issues may involve perspectives from multiple stakeholders (i.e., scientists, policymakers, community members, and industry), often leading to conflicting interests and cultural misalignments that trigger the need …

Biomass-Mediated Metastable Zinc(Ii) Oxide Nanoparticles And Its Nanocomposites For Sustainable Water Treatment, Kazi Afroza Sultana

Open Access Theses & Dissertations

Water is undeniably the most crucial resource that allows all living entities to thrive and survive. Due to a continuously growing population and the expansion of industrial sectors, water pollution has emerged as a global issue. Consequently, people face challenges in obtaining the required quantity and quality of water for their daily activities such as drinking, cooking, hygiene, and agriculture. Hence, there is a compelling need to develop an effective and environmentally friendly approach to eliminate harmful pollutants in water, promoting the establishment of a sustainable society with widespread access to clean and safe water resources. Although there are a …

Time's Up: Against Shortening Statutes Of Limitation By Employment Contract, Meredith R. Miller

Villanova Law Review (1956 - )

No abstract provided.

Effect Of Implementing Psychosocial Interventions As Pen Pals In General Chemistry, Kristofer Felix Kintner Reiser

Dissertations

General Chemistry has a high DFWI rate, disproportionately impacting students of marginalized identities (Anderson & Kim, 2006). This research investigates the hypothesis that the impacts of stereotype threat and imposter syndrome could be moderated by sharing with others through a pen pal activity. This embedded mixed method study recruited participants who were general chemistry students at a public university in the Rocky Mountain region over two years (n= 264). Participant affect was measured using the Measure of Chemistry Identity (Hosbein & Barbera, 2020), Theories of Intelligence Scale (Dweck, 2000), Chemistry Attitudes and Experiences-Self Efficacy (Dalgety et al., 2003), and general …

Impacts Of Internship Experiences On Professional Identity Development For Undergraduate Women Of Color In Engineering, Kathleen Victoria Armstrong

Dissertations

Women of color are historically underrepresented in STEM, specifically the field of engineering (National Science Board, National Science Foundation, 2019). In considering ways to assist in women of color’s retention and persistence in engineering, it is necessary to recognize the role internships, a form of experiential education, at the undergraduate level impact professional identity development. The purpose of this study was to understand how internship experiences shape professional identity development for undergraduate women of color in engineering. Using a constructivist epistemology, a theoretical framework integrating social cognitive theory and intersectionality, and an interpretive methodology; the researcher utilized semi-structured interviews and …

Energy-Aware Coordination Of Automated Vehicles, Nathan Goulet

All Dissertations

Energy is an inherently limited resource for two reasons: the sources utilized to obtain energy are limited; and the methods used most often to convert energy also generate pollutants that the planet has a limited capacity to absorb or compensate for without adverse effects. Efficiently utilizing energy is, therefore, an important topic. As around 16% of the energy consumed in the United States is by light vehicles, a significant impact can be made if vehicle energy consumption is reduced. The advent of connected and automated vehicles offers unprecedented opportunities to optimize their behavior with respect to energy consumption through trajectory …

Belonging By Design: The Exploration Of Architecture Learning Environments And Their Role In The Sense Of Belonging And Field Identity Of Black Architecture Students, Stacy Scott

All Dissertations

This research offers a comprehensive analysis of the various dimensions of belonging, isolation, and the role of identity in architecture learning environments (ALEs) for Black architecture students. In a multi-site case study, the study analyzes the experiences of Black students in the habitus that forms these ALEs at three universities with fifteen participants. Through qualitative investigation and thematic analysis, this research evaluates the obstacles these students face when endeavoring to establish meaningful connections.

The results of this study provide a greater understanding of the impact that isolation, lack of representation have on students and the significance of support-seeking activities in …

Applications Of Large Eddy Simulations To Novel Internal Combustion Concepts, Patrick O'Donnell

All Dissertations

Computational fluid dynamics (CFD) simulations of internal combustion engines (ICEs) are becoming an increasingly popular tool in the automotive industry to either explain experimentally observed trends or perform lower cost design iterations. The convenience of commercially available CFD software and advancements made in computing hardware have been the impetus behind this growing popularity. However, obtaining accurate results using these software packages is not a trivial process and requires an in-depth understanding of the underlying numerical methodology and sub models for various physical phenomena. Specific to the ICEs, CFD simulation often entails the use of models for detailed chemistry and combustion, …

Innovations In Geospatial Technologies For Water And Environmental Resource Protection, Madeleine Bolick

All Dissertations

New technologies and applications of technologies are critical to protecting environmental and water resources. Students need to be aware of these new technologies so they can be prepared to utilize them in their future careers. One such technology is using Unmanned Aerial Vehicles (UAVs) because it can be applied to a wide variety of fields such as engineering, construction, wildlife biology, agriculture, and many more. Chapter two discusses the creation of an online teaching module to introduce students to using UAVs in natural resource research and evaluates how well students respond to the education module. Overall, student familiarity with UAVs …

Variability In Anesthesia And Its Implications For Improving Patient Safety, Joshua Michael Biro

All Dissertations

Improving patient safety in anesthesia has proven to be an arduous and challenging task. Despite the many strategies and interventions to improve patient safety that have been employed, patient harm in anesthesia remains a problem. The struggle to reduce patient harm in anesthesia is both attributable to and representative of the complexity of the anesthesia system. In navigating this complex system, anesthesia providers have different approaches to how they accomplish their work, which results in variability in anesthesia practice. This variability provides an immense challenge to designing and implementing efforts to improve patient safety, as rigid interventions are often met …

Protein A And Multimodal Anion-Exchange Membrane Adsorbers For Downstream Purification Of Therapeutic Biomolecules, Joshua Osuofa

All Dissertations

This dissertation explores development and characterization of membrane chromatography tools for downstream purification of therapeutic biomolecules. Convective technologies, particularly membrane chromatography, are emerging in the field of bioseparations as an alternative to resin chromatography due to their improved throughput capability. On the forefront of emerging membrane technologies are multimodal and Protein A membrane adsorbers. The overarching theme of this dissertation research was to investigate advances in these membrane chromatography tools. The primary objective was to develop and characterize novel Protein A membrane adsorbers. A secondary objective was to characterize newly commercialized Protein A and multimodal anion exchange membrane adsorbers.

Two …

Exploring Transfer Students’ Perceptions Of Their Transition Experience In Calculus 2 At A Research Intensive Institution: A Schlossberg’S And Tinto’S Theory Approach, Steven Edalgo

All Dissertations

This study explored the lived experiences of eleven transfer students as they described their experiences in Calculus 2 at very high research land grant institutions (R1). This qualitative investigation focused on the psychological phenomenon of transition as the transfer students perceived, reflected, made sense, and understood their transition experience. Furthermore, this study explored transfer students’ understanding of how they perceive the attributes of their success or lack of success in Calculus 2.

Employing the use of Schlossberg’s Transition Framework along with Tinto’s Persistence/Departure Framework, the perceptions of the transition experience was analyzed through the lens of this conceptual framework. The …

Supporting Nontenure Faculty In Documenting Teaching Effectiveness In A Faculty Learning Community, Becky Tugman

All Dissertations

This case study project explored the benefits of peer-supported review of teaching (P-SR) as part of a faculty learning community (FLC) to help increase nontenured track faculty's confidence in submission materials for annual evaluations and faculty promotion. The high-stakes evaluation guidelines can be vague, and nontenured faculty may have limited submission support. The FLC format was used to increase submission confidence and understanding of effective teaching evidence by offering a space for collaboration and problem-solving in a collective and meaningful way. The literature supporting professional development using the FLC framework model has grown since Milton Cox introduced it in 2004. …

Investigation Of Vo2 Thin Films And Devices For Opto-Electromechanical Applications, Samee Azad

All Dissertations

Specialized and optimized low pressure direct oxidation technique have been implemented to synthesize high quality VO₂ thin films on various substrates (sapphire, SiO₂/Si, AT-cut quartz, GaN/AlGaN/GaN/Si and muscovite). Structural and surface characterization methods such as X-ray diffraction, Raman spectroscopy and atomic force microscopy have been administered on the grown VO₂ films which indicate their material quality. Transition of characteristics of the VO₂ films are caused by semiconductor metal transition (SMT). This phenomenon is attributed as the change maker in transition of resistivity and transmitted optical power through the VO₂ films. Apart the substrates mentioned, …

High-Energy Storm Events And Their Impacts On Carbon Storage In Tidal Wetlands Of South Carolina, Gavin Gleasman

All Dissertations

Atmospheric carbon dioxide (CO₂) concentrations have been increasing at an accelerating rate for the past two centuries, profoundly impacting global climate change. Atmospheric CO₂ concentrations are influenced by the global carbon cycle through physical and biogeochemical pathways. Tidal wetland environments play a vital role in the global carbon cycle by offsetting atmospheric CO₂ concentrations through their natural physiochemical processes of high autotrophic productivity, allochthonous organic matter deposition, anoxic soils, and continuous accretion which promotes carbon sequestration with long-term storage at the land-ocean margin. The Intergovernmental Panel on Climate Change (IPCC) and United States Global Change Research …

Vibration-Based Fault Diagnostics In Wind Turbine Gearboxes Using Machine Learning, Abdelrahman Amin

All Dissertations

A significantly increased production of wind energy offers a path to achieve the goals of green energy policies in the United States and other countries. However, failures in wind turbines and specifically their gearboxes are higher due to their operation in unpredictable wind conditions that result in downtime and losses. Early detection of faults in wind turbines will greatly increase their reliability and commercial feasibility. Recently, data-driven fault diagnosis techniques based on deep learning have gained significant attention due to their powerful feature learning capabilities. Nonetheless, diagnosing faults in wind turbines operating under varying conditions poses a major challenge. Signal …

Social Distortion: Disinformation, Polarization, And The Politics Of Identity In An Online World, Jennifer Duck Brown

All Dissertations

This dissertation addresses three issues that intertwine: Disinformation, polarization, and the politics of identity. Social media currently dominates how we receive our news and information. This coincides with a disinformation pandemic full of false news and propaganda running rampant online. What often ensues is a social distortion that poses as reality. Seventy-two percent of all Americans use some type of social media according to Pew Research. Not all social media is nefarious, but the design of the social platforms further aggravate how people learn and communicate. Through original and peer-reviewed mixed methods research on topics including the conspiracy theories of …

Processing, Microstructure, And Properties Of Alumina Ceramics And Silica Glass During Laser Selective Additive/Subtractive Manufacturing, Xiao Geng

All Dissertations

The heterogeneous structure is essential to obtain excellent performance in many ceramics or glass devices/components. Conventional fabrication on these heterogeneous structure composites usually requires multiple treatments, specific molds for certain structures, and post-processing to get desired structure and properties. Therefore, the flexibility of the structure is limited, and a long fabrication time is required.

Integrated additive/subtractive manufacturing and laser-based technologies have caught researchers` attention in ceramics/glass heterogeneous structure fabrication. This is because the integration of additive manufacturing (AM) with subtractive manufacturing (SM) not only maintained the advantages of AM in rapid prototyping, design complexity, and reduced material wastage but also …

Implementation Of An Early College Design In A Rural High School: Empowering Place-Conscious Leadership To Affect Change And Overcome Barriers To Innovation, Michael Timko

All Dissertations

This qualitative, improvement science, autoethnograpic case study aims to examine a unique perspective on rural research through the lens of place-conscious leadership. With an identified problem of inequity in advanced-level course offerings, which resulted in lost student opportunities and student attrition to neighboring schools, the leadership at Forest Lakes High School (FLHS) in rural South Carolina began the ambitious journey of reframing their narrative. As a scholarly researcher and administrator at FLHS, I had the unique opportunity to immerse myself fully in all aspects of this study. My dual positionality allowed me to study this process while sharing the lived …

Activated Carbon Synthesis From Lignin-Rich Byproduct Streams Of Biorefineries, Chengjun Wu

All Dissertations

Over the past decade, the production of biofuels from lignocellulosic biomass has steadily increased to offset the use of fuels from petroleum. To make biofuels cost-competitive, it is necessary to add value to the “ligno-” components (up to 30% by mass) of the biomass. Instead of just burning it for heat and electricity generation, direct conversion of lignin carbon into a product provides a complementary path to carbon capture, promoting a more environmentally conscious approach. However, the utilization of these lignin-rich byproduct streams, which are separated from the biofuels production, for industrial products can be challenging. The use of specific …

Improving Lignin Recovery From Paper Mill And Biorefinery Waste Streams Via Liquid-Phase Splitting, Carter Fitzgerald

All Dissertations

Lignin is an abundant biopolymer with significant promise due to its aromaticity. It has been targeted as a replacement for a number of petroleum-based products including adhesives, coatings, polyurethane foams, activated carbon, and carbon fibers. However, commercially available bulk lignins are too polydisperse, and contain too many residual metals from the pulping process that are detrimental to the properties of the final product.

The Sequential Liquid-lignin Recovery and Purification (SLRP) process was developed by Michael Lake and John Blackburn, in collaboration with Clemson, with the intention of creating a continuous method for recovering lignin from paper-mill black liquors. Thies and …

Advanced Quantitative Approaches To Unveil Social Inequities In Educational Contexts, Manuel J. Jiménez, Vanessa Svihla, Karl Benedict, Victor Law, Meeko Oishi

Organization, Information and Learning Sciences ETDs

Chapter 2 introduces an innovative method integrating Geographic Information Systems and Machine Learning to evaluate educational policy outcomes. This approach overcomes the limitations of traditional statistical methods and effectively analyzes complex relationships between educational data and demographic factors.

The study in Chapter 3 developed a prediction model for school report cards in New Mexico using census data and applying the methods described in Chapter 2. The accurate predictions suggested that the school accountability system disproportionately assigned failing grades to schools serving minoritized students. The study also confirmed that status measures depend more on demographics than growth measures.

The study in …

Assessing The Role Of Distance To Level I Trauma Units On Atv Rollovers, Tractor Rollovers, And Machinery Entanglement Outcomes, Andrew K. Schissel

Capstone Experience: Master of Public Health

All-Terrain Vehicle (ATV) rollovers, tractor rollovers, and machinery entanglements cause traumatic injuries to agricultural workers. Response time of first responders combined with travel to trauma units can take a significant amount of time in rural areas, potentially leading to an increased risk of fatal outcomes for those involved in these incidents. The aim of this study is to determine if distance to a level I trauma unit is a factor in the outcomes of these incidents. ATV rollovers, tractor rollovers, and machinery entanglement injuries and fatalities, collected from a 7-state Midwestern region were entered into a GIS system along with …

The Impact Of Doulas On Breastfeeding In Black Women: A Literature Review, Delaney C. Holland

Capstone Experience: Master of Public Health

This literature review was conducted to explore the impacts doulas have on breastfeeding initiation and continuation in the Black population. Black women’s breastfeeding and continuation is exceptionally low compared to white women and other races and ethnicities. Six journal articles were used to examine the relationships that doulas have on breastfeeding initiation and continuation in black communities. There was an array of study designs found throughout the articles to help support the doula and breastfeeding relationship in Black women. The results of this literature review were preliminarily positive, but more evidence is required to firmly establish the positive impact of …

Developing An Early Warning System Of Highway Slope Failure Based On In-Situ Hydraulic Conductivity Of Soil, Alinda Gupta

Civil Engineering Dissertations - Archive

Highway slope failure is globally a momentous issue. Highway slope failure poses a significant issue in transportation infrastructure. Several factors can contribute to slope failures, including geological conditions, weather events, and human activities. Weather events like heavy rainfall, cyclic shrinkage and swelling can trigger slope failures constructed on high plastic clays. It increases pore water pressure, causing soil saturation, and inducing failure. The consequences of highway slope failures are severe, ranging from traffic disruptions, road closures, and damage to vehicles and infrastructure, to potential injuries or loss of lives. Addressing and mitigating slope failure risks is crucial for ensuring the …