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A Transdisciplinary Emergent Approach For Systems And Interventions (Easi), Chaithanya Renduchintala Dec 2022

A Transdisciplinary Emergent Approach For Systems And Interventions (Easi), Chaithanya Renduchintala

Electronic Theses and Dissertations, 2020-

In modeling human behavior and social structures several factors can emerge over time this can be attributed to the availability of new data, increased complexity, changes to the organizational structure, interventions, introduction of innovative technology or services and due to improved knowledge and treatments. We hypothesize a new class of emergent decision support systems that continually evolve to account for this "Causal Drift". In this work, we illustrate the application of the Emergent Approach to Systems and Intervention (EASI™) methodology with the example of Community Intervention Activity Model (CIAM) to reduce the rate of diabetic hospitalization at the local/ county …


Modeling The Effects Of Diversity And Corporations On Participation Dynamics In Floss Ecosystems, Olivia Newton Dec 2022

Modeling The Effects Of Diversity And Corporations On Participation Dynamics In Floss Ecosystems, Olivia Newton

Electronic Theses and Dissertations, 2020-

A multitude of societal issues associated with the development of technology have emerged over the years including, but not limited to: insufficient personnel for maintenance; a lack of accessibility; the spread of harmful tools; and bias and discrimination against marginalized groups. I propose that a systems perspective is necessary to identify potential leverage points in technology production systems to influence them towards increased social good and evaluate their effectiveness for intervention. Toward this end, I conducted a mixed-methods study of a widely-adopted approach in tech production, free/libre and open source software (FLOSS) development. A survey was distributed to elicit responses …


Peat And Patty: Providing A Voice For Nature Through Animation, Clinnie Brinson Dec 2022

Peat And Patty: Providing A Voice For Nature Through Animation, Clinnie Brinson

Electronic Theses and Dissertations, 2020-

Peat and Patty is a 3D animated short story of a young scientist, Patty, and her pet parrot Peat, whose goal is to save their world from a dying ecosystem. Ultimately, they inadvertently receive help from a nearby polar bear which leads to the success of Patty's experiment. The purpose of this story is to highlight the dangers of global warming to our own ecosystem thus building eco-consciousness in viewers. We currently have natural disasters increasing in frequency, a rising global temperature, and pollution in our bodies of water (Rossati). By personifying nature, animation can invoke empathy from viewers towards …


Data Dimensionality Reduction Techniques: What Works With Machine Learning Models, Yuting Chen Dec 2022

Data Dimensionality Reduction Techniques: What Works With Machine Learning Models, Yuting Chen

Electronic Theses and Dissertations, 2020-

High-dimensional data has a wide range of applications in research, such as education, health, social media, and many other research fields. However, the high dimensionality of data can raise many problems for data analyses. This study focuses on commonly used techniques of dimensionality reduction for machine learning models, which play an essential and inevitable role in data prepossessing and statistical analysis. The main issues of high-dimensional data for machine learning tasks include the accuracy of data classification and visualization in machine learning models. Therefore, in this study, machine learning algorithms are used to predict and classify datasets to evaluate the …


Polyelectrolyte Functionalized Forward Osmosis For Water Reclamation From Synthetic Spacecraft Wastewater, Alina Ripp Dec 2022

Polyelectrolyte Functionalized Forward Osmosis For Water Reclamation From Synthetic Spacecraft Wastewater, Alina Ripp

Electronic Theses and Dissertations, 2020-

This study investigated the application of a polyelectrolyte (PE)-assisted metallic iron nanoparticle-integrated forward osmosis (FO) membrane to treat synthetic spacecraft wastewater comprising urea, ammonium carbonate, and linear alkylbenzene sulfonate (LAS). The draw solution (MgSO4) diluted via the FO operation was further treated using a nanofiltration (NF) membrane aimed at producing potable quality water by the FO-NF hybrid process. A cellulose triacetate FO membrane was functionalized by layer-by-layer deposition of polyallylamine hydrochloride (PAH) and polyacrylic acid (PAA) followed by incorporating zero valent iron nanoparticles (ZVINP) within the "bilayers". It required 14 bilayers to ensure a uniform coating as demonstrated via scanning …


High Performance And Low Cost Passivating, Carrier-Selective Contacts For Silicon Photovoltaics, Jannatul Ferdous Mousumi Dec 2022

High Performance And Low Cost Passivating, Carrier-Selective Contacts For Silicon Photovoltaics, Jannatul Ferdous Mousumi

Electronic Theses and Dissertations, 2020-

The world is now focusing on expanding renewable energy sources to reduce the carbon footprint and mitigate climate change. Solar energy is one of the most environment-friendly and fastest-growing renewable energy sources in the present world. While crystalline silicon (c-Si) based devices dominate the global photovoltaics (PV) market with a current share of 95%, it is still challenging to achieve the theoretical efficiency limit of 29.4% with this technology due to a few performance limiting factors. Contact recombination losses are dominant among them which result from the recombination of photo-generated charge carriers due to the presence of defects at the …


Low-Resource Machine Learning Techniques For The Analysis Of Online Social Media Textual Data, Toktam Amanzadeh Oghaz Dec 2022

Low-Resource Machine Learning Techniques For The Analysis Of Online Social Media Textual Data, Toktam Amanzadeh Oghaz

Electronic Theses and Dissertations, 2020-

Low-resource and label-efficient machine learning methods can be described as the family of statistical and machine learning techniques that can achieve high performance without needing a substantial amount of labeled data. These methods include both unsupervised learning techniques, such as LDA, and supervised methods, such as active learning, each providing different benefits. Thus, this dissertation is devoted to the design and analysis of unsupervised and supervised techniques to provide solutions for the following problems: Unsupervised narrative summary extraction for social media content, Social media text classification with Active Learning (AL), Investigating restrictions and benefits of using Curriculum Learning (CL) for …


Adaptive Analytic Continuation For The State Transition Tensors Of The Two-Body Problem, Tahsinul Haque Tasif Dec 2022

Adaptive Analytic Continuation For The State Transition Tensors Of The Two-Body Problem, Tahsinul Haque Tasif

Electronic Theses and Dissertations, 2020-

In the past few decades, Kessler syndrome (named after Donald J. Kessler) has become a point of concern in the field of Space Situational Awareness and the future of space missions. It refers to a scenario, where space debris in Earth's orbits collides and creates an exponential increase in space debris numbers leading to more collisions and more debris. In order to handle the resulting challenges like conjunction analysis, tracking, and probability of collisions, the State Transition Matrix (STM) and Tensors (STTs) of the orbit problem play a significant role. In addition, STM and STTs are ubiquitous in spaceflight dynamics, …


Observation Of Novel Phases Of Quantum Matter Beyond Topological Insulator, Sabin Regmi Dec 2022

Observation Of Novel Phases Of Quantum Matter Beyond Topological Insulator, Sabin Regmi

Electronic Theses and Dissertations, 2020-

Because of the unique electronic properties, intriguing novel phenomena, and potentiality in quantum device applications, the quantum materials with non-trivial band structures have enticed a bulk of research works over the last two decades. The experimental discovery of the three-dimensional topological insulators (TIs) - bulk insulators with surface conduction via spin-polarized electrons - kicked off the flurry of research interests towards such materials, which resulted in the experimental discovery of new topological phases of matter beyond TIs. The topological semimetallic phase in Dirac, Weyl, and nodal-line semimetals is an example, where the classification depends on the dimensionality, degeneracy, and symmetry …


Distributed Detection In Energy Harvesting Wireless Sensor Networks, Ghazaleh Ardeshiri Dec 2022

Distributed Detection In Energy Harvesting Wireless Sensor Networks, Ghazaleh Ardeshiri

Electronic Theses and Dissertations, 2020-

A conventional wireless sensor networks (WSN), consisting of sensors powered by nonrechargeable batteries, has a strictly limited lifetime. Energy harvesting (EH) from the environment is a promising solution to address the energy constraint problem in conventional WSNs, and to render these networks to self-sustainable networks with perpetual lifetimes. In EH-powered WSNs, where sensors are capable of harvesting and storing energy, power control is necessary to balance the rates of energy harvesting and energy consumption for data transmission. In addition, wireless communication channels change randomly in time due to fading. These together prompt the need for developing new power control strategies …


Data-Driven Power System Stability Analysis And Control, Jian Xie Dec 2022

Data-Driven Power System Stability Analysis And Control, Jian Xie

Electronic Theses and Dissertations, 2020-

In recent years, with the expansion of power system size, the increase of interconnection and the use of large-scale renewable energy, power system stability and safe operations have become more prominent, causing challenges to the normal operation of power grid. Traditional analysis rely on detailed models of the system. But for real power systems, the operating state of the system is variable, and the model-based analysis methods may not accurately reflect the real operating state of the system. Therefore, this dissertation is focused on data-driven stability analysis and control. First, a method for locating the oscillation source of multi-machine systems …


The Y-Chromosome's Role In Sexually Dimorphic Evolution And Mother's Curse Compensation, Tobias Nielsen Dec 2022

The Y-Chromosome's Role In Sexually Dimorphic Evolution And Mother's Curse Compensation, Tobias Nielsen

Electronic Theses and Dissertations, 2020-

The Y-chromosome and mitochondria (containing mtDNA) appear entirely dissimilar, the former being a sex chromosome found in the nucleus and the latter an organelle with thousands of copies in the cytoplasm. However, both experience uniparental inheritance, with Y-chromosomes being patrilineal and mitochondria matrilineal. This leads to various other similarities including haploidy, high mutation rates, and limited or lack of genetic recombination. Moreover, the low number of protein-coding genes contained on both led to the belief that neither contributes significantly to the adaptive evolution of complex traits. However, recent studies show the Y-chromosome and mitochondria both influence roughly 10% of male …


Torward Real-World Cross-View Image Geo-Localization, Sijie Zhu Dec 2022

Torward Real-World Cross-View Image Geo-Localization, Sijie Zhu

Electronic Theses and Dissertations, 2020-

Cross-view image geo-localization aims to determine the locations of street-view query images by searching in a GPS-tagged reference image database from aerial view. One fundamental challenge is the dramatic view-point/domain difference between the street-view query images and aerial-view reference images. Recent works have made great progress on bridging the domain gap with advanced deep learning techniques and geometric prior knowledge, i.e. the query is aligned at the center of one aerial-view reference image (spatial alignment) and the orientation relationship between the two views is known (orientation alignment). However, such prior knowledge of the geometry correspondence of the two views is …


Multi-Plane Light Conversion: Devices And Applications, Yuanhang Zhang Dec 2022

Multi-Plane Light Conversion: Devices And Applications, Yuanhang Zhang

Electronic Theses and Dissertations, 2020-

Multi-plane light conversion (MPLC) has recently been developed as a versatile tool for manipulating spatial distributions of the optical field through repeated phase modulations. An MPLC Device consists of a series of phase masks separated by free-space propagation. It can convert one orthogonal set of beams into another orthogonal set through unitary transformation, which is useful for a number of applications. In telecommunication, for example, mode-division multiplexing (MDM) is a promising technology that will enable continued scaling of capacity by employing spatial modes of a single fiber. MPLC has shown great potential in MDM devices with ultra-wide bandwidth, low insertion …


Processing And Characterization Of Ultra High Temperature And High Conductive Composites, Haonan Song Dec 2022

Processing And Characterization Of Ultra High Temperature And High Conductive Composites, Haonan Song

Electronic Theses and Dissertations, 2020-

There are significant challenges for materials in extreme environments for a variety of applications such as aircraft engines, gas turbines, nuclear reactors, re-entry vehicles, and hypersonic structures. Ceramic matrix composites (CMCs) could be ideal candidates to meet these stringent requirements for materials due to their high melting temperatures, high oxidation, corrosion and ablation resistance, low creep, and thermal cycling behavior in such extreme environments. Particularly, continuous fibers can bridge cracks in CMCs and therefore improve the strength and fracture toughness of composites. Metal matrix ceramics are important materials in various industries, such as aerospace and automobile. MMCs have excellent mechanical …


High Voltage Aqueous Electrolyte Based Structural Supercapacitors For Electric Vehicles, Deepak Pandey Dec 2022

High Voltage Aqueous Electrolyte Based Structural Supercapacitors For Electric Vehicles, Deepak Pandey

Electronic Theses and Dissertations, 2020-

The current electric vehicles (EVs) face many challenges like limited charge capacity, low miles/charge, and long charging times. Herein, these issues are addressed by developing "energized composite," which is a multifunctional supercapacitor-based energy-storing carbon fiber reinforced polymer composite that can store supplemental electric energy and function as the body shell of EV's. This is achieved by developing a unique design, vertically aligning graphene sheets on carbon fiber electrodes and depositing metal oxides to obtain high energy density electrodes. A high-strength multilayer composite is fabricated using an alternate layer pattern configuration of epoxy and polyacrylamide gel electrolyte. The composite so developed …


Advanced Deep Learning Methodologies For Deepfake Detection, Aminollah Khormali Dec 2022

Advanced Deep Learning Methodologies For Deepfake Detection, Aminollah Khormali

Electronic Theses and Dissertations, 2020-

The recent advances in the field of Artificial Intelligence (AI), particularly Generative Adversarial Networks (GANs) and an abundance of training samples along with robust computational resources have significantly propelled the field of AI-generated fake information in all kinds, e.g., deepfakes. Deepfakes are among the most sinister types of misinformation, posing large-scale and severe security and privacy risks targeting critical governmental institutions and ordinary people across the world. The fact that deepfakes are AI-generated digital content and not actual events captured by a camera implies that they still can be detected using advanced AI models. Although the deepfake detection task has …


Progress In Chaos: Cash Transfers And Women Economic Empowerment Amidst Climate Change And Violent Conflicts In West Africa, Jennifer Obado Joel Dec 2022

Progress In Chaos: Cash Transfers And Women Economic Empowerment Amidst Climate Change And Violent Conflicts In West Africa, Jennifer Obado Joel

Electronic Theses and Dissertations, 2020-

Do cash transfers shift gender norms of economic relations within households and communities during crises? This study explores the effect of social protection programs like cash transfers on women's economic empowerment in contexts where climate change and violent conflicts co-occur. Cash transfers have become a policy of choice for governments and development agencies seeking to alleviate poverty, address economic and political grievances, and build individual and community resilience to climate change. Due to the recent popularity of cash transfers, there needs to be more scholarship on its effect on women's intra-household economic agency and voice in communities. Therefore, this study …


Ceria Defect Engineering Using Thin-Films/Ald And Biological Applications, Udit Kumar Dec 2022

Ceria Defect Engineering Using Thin-Films/Ald And Biological Applications, Udit Kumar

Electronic Theses and Dissertations, 2020-

Ceria nanostructures have been utilized for various engineering applications due to their unique defect structure, enabling them to have regenerative redox properties. The ability to shuttle between Ce3+ and Ce4+ oxidation states extends to unique properties. Defect level in ceria is usually expressed in the Ce3+/Ce4+ ratio. It can be achieved by varying the size(0 to 3D), morphologies, dopants, hetero-nanostructures, and external stimuli. However, it is still a challenge to have precise control over defect structures in the ceria lattice. The current study aims to explore the thin film deposition techniques for cerium oxide using ALD (Atomic layer deposition) and …


Extracellular Vesicle-Associated Biomolecules As Potential Biomarkers For Alzheimer's Disease Diagnosis, Lina Bedoya Martinez Dec 2022

Extracellular Vesicle-Associated Biomolecules As Potential Biomarkers For Alzheimer's Disease Diagnosis, Lina Bedoya Martinez

Electronic Theses and Dissertations, 2020-

Alzheimer's disease (AD) involves progressive neurodegeneration leading to the loss of normal neuronal function. Extracellular accumulation of amyloid-beta (Aß), through the abnormal cleavage of the amyloid precursor protein (APP) by ß- and γ-secretases, is one of the hallmarks of AD. Current research focuses on finding potential candidates for biomarkers and techniques with improved sensitivity for early disease detection. Extracellular vesicles (EVs) found in body fluids are a source of biomarkers for AD diagnosis. EVs transport pathologically significant biomolecules, like nucleic acids and proteins, across the blood-brain barrier, mediating local and distant cell-to-cell communication. Therefore, this study evaluated EV-associated DNA and …


The Facile Preparation Of Bis(Imino)Pyridine Complexes Via Mechanochemistry And Inorganic Synthons Via Benign Reductants, Thomas Shaw Dec 2022

The Facile Preparation Of Bis(Imino)Pyridine Complexes Via Mechanochemistry And Inorganic Synthons Via Benign Reductants, Thomas Shaw

Electronic Theses and Dissertations, 2020-

This thesis is comprised of two key themes: (i) leveraging mechanochemical synthetic methods for the green preparation of bis(imino)pyridine ligands and associated first row transition metal coordination complexes, and (ii) the preparation and characterization of both historic and novel mid-valent inorganic synthons via the use of dimethylphenylsilane as a stoichiometric reducing agent. The first portion of this thesis highlights the utilization of solvent-free vibratory ball-milling in lieu of traditional, solvent-based refluxes. A variety of both bis(imino)pyridine ligands and complexes were formed in drastically reduced timeframes with solvent-economical work-up procedures. This methodology was also leveraged for the isolation of acetyl(imino)pyridine ligands …


Synthesis, Characterization, And Modeling Of Thermo-Responsive Hydrogels With Improved Mechanical Strength And Swelling Kinetics, Marilu Ortiz Nieves Jan 2022

Synthesis, Characterization, And Modeling Of Thermo-Responsive Hydrogels With Improved Mechanical Strength And Swelling Kinetics, Marilu Ortiz Nieves

Electronic Theses and Dissertations, 2020-

Hydrogels have been extensively studied for use in applications such as tissue engineering, drug delivery systems, wound dressing, actuators, valves, and sensors in Micromechanical Systems (MEMS), among others. Thermo-responsive hydrogels in particular pose various advantages such as their capability to respond to an external stimulus and reverse the response when the stimulus is removed and the ability to imbibe a significant amount of solvent and increase their volume by over 1000%. Extensive research has been conducted to tune and improve hydrogel’s rate and degree of swelling and mechanical properties. Previous work showed that when synthetic clay (Laponite) is cross-linked with …


Graph Neural Networks For Improved Interpretability And Efficiency, Patrick Pho Jan 2022

Graph Neural Networks For Improved Interpretability And Efficiency, Patrick Pho

Electronic Theses and Dissertations, 2020-

Attributed graph is a powerful tool to model real-life systems which exist in many domains such as social science, biology, e-commerce, etc. The behaviors of those systems are mostly defined by or dependent on their corresponding network structures. Graph analysis has become an important line of research due to the rapid integration of such systems into every aspect of human life and the profound impact they have on human behaviors. Graph structured data contains a rich amount of information from the network connectivity and the supplementary input features of nodes. Machine learning algorithms or traditional network science tools have limitation …


Synergistic Impacts Of Climate Change And Human Induced Stressors On The Apalachicola Bay Food Web, Kira Allen Jan 2022

Synergistic Impacts Of Climate Change And Human Induced Stressors On The Apalachicola Bay Food Web, Kira Allen

Electronic Theses and Dissertations, 2020-

Apalachicola Bay, an estuary located in northwest Florida, is likely to experience an increase in climate change and human-induced stressors, such as sea level rise and changes in freshwater inflow, in the future. A coupled hydrodynamic and food web modeling approach was used to simulate future scenarios of low and high river flow and sea level rise in Apalachicola Bay from 2020 to 2049 and demonstrate the range of temporal and spatial changes in water temperature, salinity, fisheries species populations and the broader food web. Concurrent with model development, a survey of Apalachicola Bay stakeholders was conducted to assess stakeholder …


Exploration Of The Oral Microbiome In Non-Ventilated Hospitalized Patients, Kimberly Emery Jan 2022

Exploration Of The Oral Microbiome In Non-Ventilated Hospitalized Patients, Kimberly Emery

Electronic Theses and Dissertations, 2020-

Non-ventilator hospital acquired pneumonia (NV-HAP) impacts 1 in 100 hospitalized patients and is a significant patient concern due to its negative clinical outcomes. Many factors play a role in NV-HAP development: oral health, oral care, microaspiration risk, and the oral microbiome. Little is known about how the oral microbiome alters during hospitalization. This study explored changes in the oral microbiome of non-ventilated hospitalized patients over time and analyzed the relationship between the oral microbiome, pre-hospital residence, and NV-HAP. A prospective, observational design was used to recruit 46 non-ventilated adults 65 years and older from a large medical center in central …


Bayesian Spatiotemporal Modeling With Gaussian Processes, Qing He Jan 2022

Bayesian Spatiotemporal Modeling With Gaussian Processes, Qing He

Electronic Theses and Dissertations, 2020-

Bayesian spatiotemporal models have been successfully applied to various fields of science, such as ecology and epidemiology. The complicated nature of spatiotemporal patterns can be well represented through priors such as Gaussian processes. This dissertation is focused on two applications of Bayesian spatiotemporal models: a) anomaly detection for spatiotemporal data with missingness and b) zero-inflated spatiotemporal count data analysis. Missingness in spatiotemporal data prohibits anomaly detection algorithms from learning characteristic rules and patterns due to the lack of most data. This project is motivated by a challenge provided by the National Science Foundation (NSF) and the National Geospatial-Intelligence Agency (NGA). …


The Direct And Indirect Effects Of Strategic Displacement On Territorial Control In Conventional Civil War, Jennifer Hudson Jan 2022

The Direct And Indirect Effects Of Strategic Displacement On Territorial Control In Conventional Civil War, Jennifer Hudson

Electronic Theses and Dissertations, 2020-

Which strategies contribute towards a belligerent's ability to shift territorial control in its favor more quickly than others? This dissertation advances a theory of territorial control dynamics in conventional civil war that places the civilian population at the center of the analysis. Existing scholarship explaining territorial control in conventional civil war has emphasized the role of relative military capabilities, direct military confrontations aimed at territorial conquest, and the existence of established zones of control, with civilians generally residing in areas clearly dominated by one party or another, not in contested areas. As such, theory holds that this makes the civilian …


Plasmonic Sensor Based Detection Of Dopamine, Sang Lee Jan 2022

Plasmonic Sensor Based Detection Of Dopamine, Sang Lee

Electronic Theses and Dissertations, 2020-

With a rapidly ageing population, neurological diseases are becoming increasingly relevant in the design of public health policies and strategies in western societies. In the last decades, biochemical research has consistently shown the critical role that neurotransmitters and their associated metabolites play as biomarkers in tracking and diagnosis of different brain disorders and cancers. In particular, dopamine, an organic electrochemical neurotransmitter, has been shown to be paramount for the proper functioning of the neural system. Dopamine's dysfunction, has been shown to underlie the pathogenesis in several neurological disorders such as Parkinson's disease, depression, chronic schizophrenia and psychosis. Unfortunately, currently available …


A Unified Tool For Adaptive Collocation Techniques Applied To Solving Optimal Control Problems, Bethany Kelly Jan 2022

A Unified Tool For Adaptive Collocation Techniques Applied To Solving Optimal Control Problems, Bethany Kelly

Electronic Theses and Dissertations, 2020-

In this work, a user-friendly MATLAB tool is introduced to solve nonlinear optimal control problems by applying collocation techniques using Coupled Radial Basis Functions (CRBFs). CRBFs are a new class of Radial Basis Functions combined with a conical spline r^5, which provides the advantage of insensitivity to the shape parameter while maintaining accuracy and robustness. To solve optimal control problems, software tools are often employed to implement numerical methods and apply advanced techniques to solving differential equations. Although several commercial software tools exist for solving optimal control problems, such as ICLOCS2, GPOPS, and DIDO, there are no options available that …


Development Of A Dual-Mode Cmos Microelectrode Array For The Simultaneous Study Of Electrochemical And Electrophysiological Activities Of The Brain, Geoffrey Mulberry Jan 2022

Development Of A Dual-Mode Cmos Microelectrode Array For The Simultaneous Study Of Electrochemical And Electrophysiological Activities Of The Brain, Geoffrey Mulberry

Electronic Theses and Dissertations, 2020-

Medical diagnostic devices are in high demand due to increasing cases of neurodegenerative diseases in the aging population and pandemic outbreaks in our increasingly connected global community. Devices capable of detecting the presence of a disease in its early stages can have dramatic impacts on how it can be treated or eliminated. High cost and limited accessibility to diagnostic tools are the main barriers preventing potential patients from receiving a timely disease diagnosis. This dissertation presents several devices that are aimed at providing higher quality medical diagnostics at a low cost. Brain function is commonly studied with systems detecting the …