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2022

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Applying Data Science And Machine Learning To Understand Health Care Transition For Adolescents And Emerging Adults With Special Health Care Needs, Lisamarie Turk Dec 2022

Applying Data Science And Machine Learning To Understand Health Care Transition For Adolescents And Emerging Adults With Special Health Care Needs, Lisamarie Turk

Nursing ETDs

A problem of classification places adolescents and emerging adults with special health care needs among the most at risk for poor or life-threatening health outcomes. This preliminary proof-of-concept study was conducted to determine if phenotypes of health care transition (HCT) for this vulnerable population could be established. Such phenotypes could support development of future studies that require data classifications as input. Mining of electronic health record data and cluster analysis were implemented to identify phenotypes. Subsequently, a machine learning concept model was developed for predicting acute care and medical condition severity. Three clusters were identified and described (Cluster 1, n …


Using Materialized Views For Answering Graph Pattern Queries, Michael Lan Dec 2022

Using Materialized Views For Answering Graph Pattern Queries, Michael Lan

Dissertations

Discovering patterns in graphs by evaluating graph pattern queries involving direct (edge-to-edge mapping) and reachability (edge-to-path mapping) relationships under homomorphisms on data graphs has been extensively studied. Previous studies have aimed to reduce the evaluation time of graph pattern queries due to the potentially numerous matches on large data graphs.

In this work, the concept of the summary graph is developed to improve the evaluation of tree pattern queries and graph pattern queries. The summary graph first filters out candidate matches which violate certain reachability constraints, and then finds local matches of query edges. This reduces redundancy in the representation …


Android Security: Analysis And Applications, Raina Samuel Dec 2022

Android Security: Analysis And Applications, Raina Samuel

Dissertations

The Android mobile system is home to millions of apps that offer a wide range of functionalities. Users rely on Android apps in various facets of daily life, including critical, e.g., medical, settings. Generally, users trust that apps perform their stated purpose safely and accurately. However, despite the platform’s efforts to maintain a safe environment, apps routinely manage to evade scrutiny. This dissertation analyzes Android app behavior and has revealed several weakness: lapses in device authentication schemes, deceptive practices such as apps covering their traces, as well as behavioral and descriptive inaccuracies in medical apps. Examining a large corpus of …


Carrier Transport Engineering In Wide Bandgap Semiconductors For Photonic And Memory Device Applications, Ravi Teja Velpula Dec 2022

Carrier Transport Engineering In Wide Bandgap Semiconductors For Photonic And Memory Device Applications, Ravi Teja Velpula

Dissertations

Wide bandgap (WBG) semiconductors play a crucial role in the current solid-state lighting technology. The AlGaN compound semiconductor is widely used for ultraviolet (UV) light-emitting diodes (LEDs), however, the efficiency of these LEDs is largely in a single-digit percentage range due to several factors. Until recently, AlInN alloy has been relatively unexplored, though it holds potential for light-emitters operating in the visible and UV regions. In this dissertation, the first axial AlInN core-shell nanowire UV LEDs operating in the UV-A and UV-B regions with an internal quantum efficiency (IQE) of 52% are demonstrated. Moreover, the light extraction efficiency of this …


Photonic Monitoring Of Atmospheric Fauna, Adrien P. Genoud Dec 2022

Photonic Monitoring Of Atmospheric Fauna, Adrien P. Genoud

Dissertations

Insects play a quintessential role in the Earth’s ecosystems and their recent decline in abundance and diversity is alarming. Monitoring their population is paramount to understand the causes of their decline, as well as to guide and evaluate the efficiency of conservation policies. Monitoring populations of flying insects is generally done using physical traps, but this method requires long and expensive laboratory analysis where each insect must be identified by qualified personnel. Lack of reliable data on insect populations is now considered a significant issue in the field of entomology, often referred to as a “data crisis” in the field. …


Integrated Machine Learning And Optimization Approaches, Dogacan Yilmaz Dec 2022

Integrated Machine Learning And Optimization Approaches, Dogacan Yilmaz

Dissertations

This dissertation focuses on the integration of machine learning and optimization. Specifically, novel machine learning-based frameworks are proposed to help solve a broad range of well-known operations research problems to reduce the solution times. The first study presents a bidirectional Long Short-Term Memory framework to learn optimal solutions to sequential decision-making problems. Computational results show that the framework significantly reduces the solution time of benchmark capacitated lot-sizing problems without much loss in feasibility and optimality. Also, models trained using shorter planning horizons can successfully predict the optimal solution of the instances with longer planning horizons. For the hardest data set, …


Helioseismic Diagnostics Of Active Regions And Their Magnetic Fields, John T. Stefan Dec 2022

Helioseismic Diagnostics Of Active Regions And Their Magnetic Fields, John T. Stefan

Dissertations

While two and a half decades of nearly constant observation by the Solar and Heliospheric Observatory (SOHO) and the Solar Dynamics Observatory (SDO) spacecraft have yielded key insights into the structure and dynamics of active regions, it is still unclear if active regions can be identified before emerging on the solar surface and, once emerged, whether the subsurface structure of an active region’s magnetic field can be measured. Regarding the dynamical processes associated with active regions, the height and mechanism of sunquake excitation remains poorly understood. To answer these questions, a comprehensive survey of active region magnetic fields and their …


Hydrodynamic Investigation Of The Discharge Of Complex Fluids From Dispensing Bottles Using Experimental And Computational Approaches, Baran Teoman Dec 2022

Hydrodynamic Investigation Of The Discharge Of Complex Fluids From Dispensing Bottles Using Experimental And Computational Approaches, Baran Teoman

Dissertations

The discharge of non-Newtonian, complex fluids through orifices of industrial tanks, pipes, dispensers, or packaging containers is a ubiquitous but often problematic process because of the complex rheology of such fluids and the geometry of the containers. This, in turn, reduces the discharge rate and results in residual fluid left in the container, often referred to as heel. Heel formation is undesired in general, since it causes loss of valuable material, container fouling, and cross-contamination between batches. Heel may be of significant concern not only in industrial vessels but also in consumer packaging. Despite its relevance, the research in this …


Interactions Of Amyloid Peptides With Lipid Membranes, Yanxing Yang Dec 2022

Interactions Of Amyloid Peptides With Lipid Membranes, Yanxing Yang

Dissertations

The aggregation of amyloid proteins into fibrils is a hallmark of several diseases including Alzheimer’s (AD), Parkinson’s, and Type II diabetes. This aggregation process involves the formation of small size oligomers preceding the formation of insoluble fibrils. Recent studies have shown that these oligomers are more likely to be responsible for cell toxicity than fibrils. A possible mechanism of toxicity involves the interaction of oligomers with the cell membrane compromising its integrity. In particular, oligomers may form pore-like structures in the cell membrane affecting its permeability or they may induce lipid loss via a detergent-like effect. This dissertation aims to …


Bioremediation Of Petroleum Hydrocarbons In Coastal Sediments, Charbel Abou Khalil Dec 2022

Bioremediation Of Petroleum Hydrocarbons In Coastal Sediments, Charbel Abou Khalil

Dissertations

The biodegradation of dispersed crude oil in the ocean is relatively rapid (a half-life of a few weeks). However, it is often much slower on shorelines, usually attributed to low moisture content, nutrient limitation, and higher oil concentrations in beaches than in dispersed plumes. Another factor may be the increased salinity of the upper intertidal and supratidal zones since these parts of the beach are potentially subject to prolonged evaporation and only intermittent inundation. Therefore, two laboratory experiments are conducted to investigate whether such an increase in porewater salinity results in additional inhibitory effects on oil biodegradation in seashores.

In …


Combustion Soot Nanoparticles: Mechanism Of Restructuring And Mechanical Properties, Ali Hasani Dec 2022

Combustion Soot Nanoparticles: Mechanism Of Restructuring And Mechanical Properties, Ali Hasani

Dissertations

Soot, a product of incomplete combustion of fossil fuels, is a global warming agent. The effect of soot particles on climate depends on their morphology. Freshly released soot particles are fractal lacey aggregates, but they often appear collapsed in atmospheric samples collected away from emission sources. A body of work has concluded that the collapse is caused by liquid shells when they form by vapor condensation around soot aggregates. However, some recent studies argue that soot remains fractal even when engulfed by the shells, collapsing only when the shells evaporate. To reconcile this disagreement, the effects of the condensation and …


Assessing The Health Effects Of Climate Change, Social Vulnerability, And Environmental Justice In Camden County, New Jersey, Daniil Ivanov Dec 2022

Assessing The Health Effects Of Climate Change, Social Vulnerability, And Environmental Justice In Camden County, New Jersey, Daniil Ivanov

Theses

Climate change negatively impacts health, while socially vulnerable and overburdened communities disproportionately experience climate change and negative health determinants. Camden County is used as a case study for analyzing environment, socioeconomics, and health. Environmental variables—PM2.5 and land cover of impervious surfaces, floodplains, and forests—were compared to the CDC Social Vulnerability Index (SVI) at the census tract level, finding significant correlations between land cover, air quality, and the SVI. The overburdened communities defined by the NJ Environmental Justice Law experienced a significantly higher incidence of emergency department visitation for respiratory, circulatory, and mental illnesses than non-overburdened communities. Health outcomes were compared …


Machine Learning-Based Data Analytics For Understanding Space Weather And Climate, Yasser Abduallah Dec 2022

Machine Learning-Based Data Analytics For Understanding Space Weather And Climate, Yasser Abduallah

Dissertations

This dissertation addresses multiple crucial problems in space weather and climate, presenting new machine learning-based data analytics algorithms and models for tackling the problems.

First, the dissertation presents two new approaches to predicting solar flares. One approach, called DeepSun, predicts solar flares by utilizing a machine-learning-as-a-service (MLaaS) platform. The DeepSun system provides a friendly interface for Web users and an application programming interface (API) for remote programming users. It adopts an ensemble learning method that employs several machine learning algorithms to perform multiclass flare prediction. The other approach, named SolarFlareNet, forecasts the occurrence of solar flares within the next 24 …


Host-Pathogen Interactions In A Changing World: Microbes, Mucosal Defenses, And Multiple Hosts, Brandon C. Labumbard Dec 2022

Host-Pathogen Interactions In A Changing World: Microbes, Mucosal Defenses, And Multiple Hosts, Brandon C. Labumbard

Graduate Doctoral Dissertations

As fungal diseases continue to emerge, research increasingly focuses on host-microbiome interactions and links to disease. Certain skin-associated microbes may benefit hosts by protecting them from invading pathogens. Seasonal changes in the host environment can also result in shifts in the microbial community and pathogen virulence – potentially influencing disease dynamics. I investigated how cutaneous microbial communities differ across hosts, seasons, and Batrachochytrium dendrobatidis (Bd) infection status by sequencing the microbial communities of 1,100 leopard frogs at five locations across the US. Percent anti-Bd function varied seasonally and with Bd infection status. Bacterial communities also varied across locations and time. …


Design Framework Of Uav-Based Environment Sensing, Localization, And Imaging System, Yue Sun Dec 2022

Design Framework Of Uav-Based Environment Sensing, Localization, And Imaging System, Yue Sun

Graduate Doctoral Dissertations

In this dissertation research, we develop a framework for designing an Unmanned Aerial Vehicle or UAV-based environment sensing, localization, and imaging system for challenging environments with no GPS signals and low visibility. The UAV system relies on the various sensors that it carries to conduct accurate sensing and localization of the objects in an environment, and further to reconstruct the 3D shapes of those objects. The system can be very useful when exploring an unknown or dangerous environment, e.g., a disaster site, which is not convenient or not accessible for humans. In addition, the system can be used for monitoring …


Non-Traditional Methods For The Green Synthesis Of Fine Chemicals, Tara Renée Mooney Dec 2022

Non-Traditional Methods For The Green Synthesis Of Fine Chemicals, Tara Renée Mooney

Graduate Masters Theses

Herein, the advancement of microwave-assisted flow synthesis is reviewed and the green nitration of arenes is investigated. First, microwave-assisted flow systems are described, followed by their synthetic and environmental applications. Microwave-assisted flow synthesis has been applied successfully in organic, inorganic, material, and biochemical syntheses as well as environmental applications such as water desalination and the removal of volatile organic compounds from the atmosphere. In the second part of the Thesis, the methodological development of the first catalyst and solvent-free nitration of m-xylene using only nitric acid is detailed. This environmentally friendly reaction proceeds without the use of harsh Brønsted acids, …


A Neural Analysis-Synthesis Approach To Learning Procedural Audio Models, Danzel Serrano Dec 2022

A Neural Analysis-Synthesis Approach To Learning Procedural Audio Models, Danzel Serrano

Theses

The effective sound design of environmental sounds is crucial to demonstrating an immersive experience. Classical Procedural Audio (PA) models have been developed to give the sound designer a fast way to synthesize a specific class of environmental sounds in a physically accurate and computationally efficient manner. These models are controllable due to the choice of parameters from analyzing a class of sound. However, the resulting synthesis lacks the fidelity for the preferred immersive experience; thus, the sound designer would rather search through an extensive database for real recordings of a target sound class. This thesis proposes the Procedural audio Variational …


Methods For Drone Trajectory Analysis Of Bottlenose Dolphins (Tursiops Truncatus), Jillian D. Bliss Dec 2022

Methods For Drone Trajectory Analysis Of Bottlenose Dolphins (Tursiops Truncatus), Jillian D. Bliss

Theses and Dissertations

With the increase in the use of UAS (Unmanned Aerial Systems) for marine mammal research, there is a need for the development of methods of analysis to transform UAS high resolution video into quantitative data. This study sought to develop a preliminary method of analysis that would quantify and present a way to visualize the dynamics and relative spatial distribution and changes in distribution of bottlenose dolphins (Tursiops truncatus) in the waters of Turneffe Atoll, Belize. This approach employs a previously developed video tracking program ‘Keypoint Tracking’ that enables manual tracking of individual dolphins and the creation of …


Randomized Algorithms For Resource Allocation In Device To Device Communication., Subhankar Ghosal Dr. Dec 2022

Randomized Algorithms For Resource Allocation In Device To Device Communication., Subhankar Ghosal Dr.

Doctoral Theses

In device to device (D2D) communication, two users residing in close proximity can directly communicate between them, through a common channel, without the need of a base station. A pair of D2D users forms a link and a channel needs to be allocated to it. The interference relationship among the active links at time t is modelled as an interference graph g(t). To establish interference-free communication, we have to assign a channel vector C(t) and a power vector corresponding to the active links such that the required signal to interference plus noise ratio (SINR) is satisfied for each link. Since …


Towards Parking Lot Occupancy Assessment Using Aerial Imagery And Computer Vision, John Jewell Dec 2022

Towards Parking Lot Occupancy Assessment Using Aerial Imagery And Computer Vision, John Jewell

Electronic Thesis and Dissertation Repository

Advances in Computer Vision and Aerial Imaging have enabled countless downstream applications. To this end, aerial imagery could be leveraged to analyze the usage of parking lots. This would enable retail centres to allocate space better and eliminate the parking oversupply problem. With this use case in mind, the proposed research introduces a novel framework for parking lot occupancy assessments. The framework consists of a pipeline of components that map a sequence of image sets spanning a parking lot at different time intervals to a parking lot turnover heatmap that encodes the frequency each parking stall was used. The pipeline …


Hybrid Life Cycles In Software Development, Eric Vincent Schoenborn Dec 2022

Hybrid Life Cycles In Software Development, Eric Vincent Schoenborn

Culminating Experience Projects

This project applied software specification gathering, architecture, work planning, and development to a real-world development effort for a local business. This project began with a feasibility meeting with the owner of Zeal Aerial Fitness. After feasibility was assessed the intended users, needed functionality, and expected user restrictions were identified with the stakeholders. A hybrid software lifecycle was selected to allow a focus on base functionality up front followed by an iterative development of expectations of the stakeholders. I was able to create various specification diagrams that express the end projects goals to both developers and non-tech individuals using a standard …


Cenozoic Extension Of The Lake Tanganyika Rift, East Africa: Structures, Tectonostratigraphy And Paleoenvironmental Reconstruction, Shaidu Shaban Dec 2022

Cenozoic Extension Of The Lake Tanganyika Rift, East Africa: Structures, Tectonostratigraphy And Paleoenvironmental Reconstruction, Shaidu Shaban

Dissertations - ALL

Active continental rifts are ideal sites for understanding the break-up of continents, and long-lived rift lake environments are known as important reservoirs for endemic communities and biodiversity. The sedimentary fill of extensional continental rifts within the East Africa Rift System (EARS) records a long history of continental extension and variable tropical climate that is unparalleled in its duration and fidelity. Continental extensional basins are sensitive to variations caused by the interplay between tectonics, sedimentary processes, and climate change. However, to discern the sedimentary fill history and its related tectonostratigraphy, as well as for reconstructing past climate changes, high-fidelity data such …


Metallacycle-Mediated Cross-Coupling As An Enabling Tool For Studies In Carbocycle Synthesis And Functionalization, Adam Barry Millham Dec 2022

Metallacycle-Mediated Cross-Coupling As An Enabling Tool For Studies In Carbocycle Synthesis And Functionalization, Adam Barry Millham

Dartmouth College Ph.D Dissertations

Natural products, specifically complex, carbocyclic natural products, have served as the inspiration for novel methods development for decades. Over that time, metallacycle-mediated cross-coupling has arisen as a powerful means for the synthesis of fused carbocycles. This work details three methods for the synthesis and functionalization of carbocyclic motifs that have been enabled by Ti-mediated cross-coupling reactions. The first of these studies include a complementary method to the Pauson–Khand reaction for the synthesis of highly substituted cyclopentenones via Ti-mediated alkyne–β-ketoester coupling. The second project, a modern approach to steroidal tetracycles, will be discussed that features: (1) an alkoxide-directed metallacycle-mediated [2+2+2] annulation …


Application Of Distributed Fiber-Optic Sensing For Pressure Predictions And Multiphase Flow Characterization, Gerald Kelechi Ekechukwu Dec 2022

Application Of Distributed Fiber-Optic Sensing For Pressure Predictions And Multiphase Flow Characterization, Gerald Kelechi Ekechukwu

LSU Doctoral Dissertations

In the oil and gas industry, distributed fiber optics sensing (DFOS) has the potential to revolutionize well and reservoir surveillance applications. Using fiber optic sensors is becoming increasingly common because of its chemically passive and non-magnetic interference properties, the possibility of flexible installations that could be behind the casing, on the tubing, or run on wireline, as well as the potential for densely distributed measurements along the entire length of the fiber. The main objectives of my research are to develop and demonstrate novel signal processing and machine learning computational techniques and workflows on DFOS data for a variety of …


The Unexpected Effectiveness Of Strategically Sparse Cooperation, Neal D. Munson Dec 2022

The Unexpected Effectiveness Of Strategically Sparse Cooperation, Neal D. Munson

Theses and Dissertations

In this work, we will show a result derived from a class of economically inspired multi-agent differential games. The result shows that in the class of games we present, only a sparse cooperation structure is needed by the agents to achieve an outcome that is in a particular sense "optimal". One may expect that to achieve such an outcome, a centralized control or full cooperation would be necessary; it is not. Not only is it not necessary - it is never necessary. We precisely characterize what kind of cooperation IS necessary to attain that kind of optimality. Only the sparsest …


Short-Range Magnetic Correlations, Spontaneous Magnetovolume Effect, And Local Distortion In Magnetic Semiconductor Mnte, Raju Baral Dec 2022

Short-Range Magnetic Correlations, Spontaneous Magnetovolume Effect, And Local Distortion In Magnetic Semiconductor Mnte, Raju Baral

Theses and Dissertations

The antiferromagnetic semiconductor MnTe has recently attracted significant interest as a potential high-performance thermoelectric material. Its promising thermoelectric properties are due in large part to short-range magnetic correlations in the paramagnetic state, which enhance the thermopower through the paramagnon drag effect. Using magnetic pair distribution function (mPDF) analysis of neutron total scattering data, we present a detailed, real-space picture of the short-range magnetic correlation in MnTe, offering a deeper view into the paramagnon drag effect and the nature of the correlated paramagnetic state. We confirm the presence of nanometer-scale antiferromagnetic correlations far into the paramagnetic state, show the evolution of …


Regression Modeling Of Complex Survival Data Based On Pseudo-Observations, Rong Rong Dec 2022

Regression Modeling Of Complex Survival Data Based On Pseudo-Observations, Rong Rong

Statistical Science Theses and Dissertations

The restricted mean survival time (RMST) is a clinically meaningful summary measure in studies with survival outcomes. Statistical methods have been developed for regression analysis of RMST to investigate impacts of covariates on RMST, which is a useful alternative to the Cox regression analysis. However, existing methods for regression modeling of RMST are not applicable to left-truncated right-censored data that arise frequently in prevalent cohort studies, for which the sampling bias due to left truncation and informative censoring induced by the prevalent sampling scheme must be properly addressed. Meanwhile, statistical methods have been developed for regression modeling of the cumulative …


Potential Benefits Of The Campus Outdoor Built Environment On Student Stress, Leading To Improved Retention, Kevin Dilliard Dec 2022

Potential Benefits Of The Campus Outdoor Built Environment On Student Stress, Leading To Improved Retention, Kevin Dilliard

Graduate Liberal Studies Theses and Dissertations

University landscape managers often ask themselves, are they making a difference? Since what they do is not a revenue-generating department, how can they validate their true worth beyond making the campus beautiful, which is excellent, but what added value do they bring? As is common practice, when economic times get tough, the landscape department budget is one of the first to be cut, but is that the wisest thing to do? This research was intended to explore the concept that the services landscape managers provide have a return on investment by providing an environment in which students can thrive and …


Folk Theories, Recommender Systems, And Human-Centered Explainable Artificial Intelligence (Hcxai), Michael Ridley Dec 2022

Folk Theories, Recommender Systems, And Human-Centered Explainable Artificial Intelligence (Hcxai), Michael Ridley

Electronic Thesis and Dissertation Repository

This study uses folk theories to enhance human-centered “explainable AI” (HCXAI). The complexity and opacity of machine learning has compelled the need for explainability. Consumer services like Amazon, Facebook, TikTok, and Spotify have resulted in machine learning becoming ubiquitous in the everyday lives of the non-expert, lay public. The following research questions inform this study: What are the folk theories of users that explain how a recommender system works? Is there a relationship between the folk theories of users and the principles of HCXAI that would facilitate the development of more transparent and explainable recommender systems? Using the Spotify music …


Advances In The Automatic Detection Of Optimization Opportunities In Computer Programs, Delaram Talaashrafi Dec 2022

Advances In The Automatic Detection Of Optimization Opportunities In Computer Programs, Delaram Talaashrafi

Electronic Thesis and Dissertation Repository

Massively parallel and heterogeneous systems together with their APIs have been used for various applications. To achieve high-performance software, the programmer should develop optimized algorithms to maximize the system’s resource utilization. However, designing such algorithms is challenging and time-consuming. Therefore, optimizing compilers are developed to take part in the programmer’s optimization burden. Developing effective optimizing compilers is an active area of research. Specifically, because loop nests are usually the hot spots in a program, their optimization has been the main subject of many optimization algorithms. This thesis aims to improve the scope and applicability of performance optimization algorithms used in …