Digital Commons Network^™

Cross-Framework Validation Of Cnn Architectures: From Pytorch To Onnx, Shreya Nandanwar

Theses and Dissertations

This research presents CIPAC (CNN Inter-framework Parameter Analysis and Comparison), a validation approach designed to ensure the integrity of Deep Learning models during their transfer between computational frameworks. Although initially tested on Convolutional Neural Networks (CNNs), CIPAC is versatile enough for various Deep Learning architectures. It goes beyond traditional methods that focus on output accuracy, by examining the models’ architecture, parameters, and components to maintain consistency after transitions, like moving from PyTorch to ONNX framework. Inspired by software architecture’s stringent validation standards, CIPAC addresses the challenges of working with Machine Learning models on different platforms, making it an essential tool …

Electrocatalytic Degradation Of Bisphenol A Using Nickel Sulfide Supported On Graphene Oxide And Cobalt Sulfide Supported On Graphene Oxide Composite Materials, Katherine Ellynn Wright

Theses and Dissertations

The degradation of bisphenol A (BPA) by nickel sulfide supported on graphene oxide (NiS/GO) and cobalt sulfide supported on graphene oxide (CoS/GO) composite materials was investigated. The catalysts were studied to determine the optimal conditions for BPA degradation using electrocatalysis. Electrocatalytic trials were performed using varying parameters, which included electrolyte concentrations of 1.0 g/L, 2.0 g/L, and 4.0 g/L Na2SO4, pHs of 2, 4, and 6, and constant currents of either 0.100 A or 0.200 A. During the reaction samples were taken before the current was applied and 30 minutes and 60 minute intervals to observe the degradation of …

Conditional Quantization For Uniform Distributions On Line Segments And Regular Polygons, Tsianna Danielle Dominguez

Theses and Dissertations

Quantization for a Borel probability measure refers to the idea of estimating a given probability by a discrete probability with support containing a finite number of elements. If in the quantization some of the elements in the support are preselected, then the quantization is called a conditional quantization. In this thesis, we have investigated the conditional quantization for the uniform distributions defined on the unit line segments and m-sided regular polygons, where m ≥ 3, inscribed in a unit circle.

A Study Of Quantitative Reasoning Instructors’ Choices And Motivations When Teaching Quantitative Reasoning For The First Time, Trish Ann Harding

Theses and Dissertations

This qualitative study delves into the instructional decision-making processes of post-secondary instructors teaching quantitative reasoning (QR) courses for the first time. The study aims to address the gap in understanding how first-time QR instructors navigate the complexities of curriculum design and pedagogical strategies, and how these experiences contribute to their professional development. The research questions center on identifying the instructional decisions made by these instructors, exploring the factors influencing their decision-making, and understanding the impact of exercising agency has on their professional development. Through in-depth exploration, this study seeks to shed light on the challenges and opportunities faced by first-time …

Unraveling The Physics Of Quasar Jets Using Hst Polarimetry, Devon Clautice

Theses and Dissertations

We present a multiwavelength study of three high-power FR II (quasar) jets -- 3C 273, PKS 0637-752, and 1150+497 -- with an emphasis on new high-quality Hubble Space Telescope (HST) optical polarimetry and Chandra X-ray Observatory imaging. Relativistic jets from active galactic nuclei transport energy and mass from the supermassive black hole’s accretion region out to Megaparsec-scale lobes, with effects that feedback into galaxy formation and cluster energetics. We build on recent work which has called into question our fundamental understanding of FR II jet physics, and suggest that highly-efficient particle acceleration must be taking place in situ …

Test And Evaluation Model For Midwater Docking Of Autonomous Underwater Vehicles, Parker Baillon

Theses and Dissertations

This research created a Test and Evaluation (T&E) model for midwater Autonomous Underwater Vehicle (AUV) capture. The creation of this model will allow for a better assessment of the feasibility of midwater AUV capture. To achieve this, the T&E model was exposed to various flow conditions to assess stability. Capturing an AUV in midwater, the area below the wave-affected zone to the sea floor, has many benefits for an AUV and its mission. AUVs basing missions from a midwater dock will not be affected by wave motions. A midwater dock can be transported to any mission site and deployed with …

Improving Static Cold Storage Life Of The Human Heart Before Transplant, Juan Sebastian Rodriguez Paez

Theses and Dissertations

Organ storage and transportation are critical steps for the success of organ transplantation. Static cold storage (SCS) of hearts for heart transplantation (HTx) remains the standard approach. However, SCS may involve damage to the tissue resulting from extended hypothermic preservation, potentially affecting organ viability. More over, the temperature distribution on and within the heart is unknown during heart transplantation. Therefore, there is an interest to study different stages of the heart transplantation process towards determining the 3D temperature distribution on and within the heart. There could be a possibility of having a hypothermic injury in different parts of the heart …

Methodologies For Optimization And Surface Heat Flux Estimation For Hybrid Thermal Protection Systems, Syed Arafun Nabi

Theses and Dissertations

Thermal protection system (TPS) plays a pivotal role in safeguarding space vehicles from extreme aerothermal heating during atmospheric entry. To ensure effective thermal management, Hybrid Thermal Protection seamlessly integrating both active and passive TPS is an innovative solution. The passive TPS consists of an insulative layer on vehicle skin to counteract the aerothermal heat. Although a thicker layer enhances insulation, a trade-off arises between the thickness of the passive layer and the spacecraft’s weight. Beneath the passive TPS layer lies the active TPS functioning as a heat exchanger where the vehicle fuel liquid is considered as coolant. The effectiveness of …

Investigating The Relationship Between Metacognition, Motivation, Self-Regulation Strategy Usage, And Physical Activity Participation, Kay Sharon Stanfield

Theses and Dissertations

There are numerous benefits associated with physical activity. Unfortunately, few people participate in enough daily activity to reap the rewards. Health professionals have explored ways to promote adherence to physical activity and healthy behavior. Evidence shows self-regulation to be a determinant of physical activity. This study investigated the relationship between self-regulation strategy usage and levels of physical activity participation. Additionally, the study examined how motivation (through the perspective of Self-Determination theory) impacts physical activity. Six behavior regulation styles correspond to the degree of motivation (from low to high) on the Self-Determination continuum. A comparison of behavior regulation styles to physical …

Artificial Neural Networks As The Solution Of Inverse Heat Conduction Problems In Multidimensional Domains, Andrea Carolina Martinez Mundarain

Theses and Dissertations

Surface heat flux measurement is essential in various industrial applications including atmospheric entry of space vehicles, machining processes, non-destructive testing and more. While direct measurement of surface heat flux is known to be a very difficult, if not infeasible, task, acquiring temperature measurement from sub- surface locations are often viable. The problem of evaluating the surface heat flux using internal temperature measurements is known as an inverse heat conduction problem (IHCP). IHCPs are considered as mathematically ill-posed as they are highly sensitive to measurement error. This research presents a solution based on the implementation of artificial neural networks (ANNs) to …

Development Of Chiral Lewis Base Catalysts For Chlorosilane-Mediated Asymmetric C-C Bond Formations, Changgong Xu

Theses and Dissertations

The chiral hydrazine is a crucial structural motif that serves as pivotal structural elements in numerous natural products and biologically significant molecules. We are particularly interested in the catalytic asymmetric reduction of hydrazones, as well as the catalytic asymmetric propargylation and allenylation of hydrazones, because they provide direct pathways to these enantio-enriched chiral building blocks. In this work, we will explore the potential of two different categories of chiral Lewis base catalysts in the said transformations.

Developed by another student in our group, axial-chiral 3,3’-triazolyl biisoquinoline N,N’-dioxides derived catalysts are tested and demonstrated its capability in activating various hydrazone …

System Identification For Motion Control Of Unmanned Aerial Vehicles Platform, Raj Ramesh Agarwal

Theses and Dissertations

Comprehensive research on Unmanned Aerial Vehicles (UAV) system identification for motion control parameters is presented in this thesis, with a focus on the necessity of precise control and improved performance. Using Pseudorandom Binary Sequence (PRBS) and Normally Distributed Random Numbers, it presents a unique technique for excitation of UAV dynamic systems. It also shows how effective random signals are in time-domain identification for precise control in a range of flying circumstances. The piece of research includes a thorough analysis and implementation of various approaches and its further improvements, highlighting the benefits and drawbacks of each. These approaches include the free …

High Intraspecific Diversity Of Pocillopora Damicornis In Southeast Asia Reflects Adaptive Potential To Climate Change, Maria Lucille Carr

Theses and Dissertations

Marine heatwaves are increasing in intensity and frequency because of increased emissions of greenhouse gases. On coral reefs, warmer temperatures cause coral bleaching, mortality, and shifts in benthic composition. However, coral bleaching responses and survival vary geographically. Several hypotheses may explain such geographical differences in thermal tolerance, including the possibility that some localities may support higher intraspecific diversity than other localities, increasing the likelihood of survival of some individuals through heatwaves. Here we assessed geographic patterns of intraspecific genetic diversity in the ubiquitous coral Pocillopora damicornis. Intraspecific genetic diversity was assessed for 428 sequences across 44 sites in the Pacific …

Constructing And Understanding Angler License Typologies And Response To Landscape Change, Michael James Lant

Theses and Dissertations

The future of conservation could hinge entirely on voluntary contributions of individualsand their relationship with landscape features. Conservation funding is becoming increasingly unstable, shifting from large non-governmental organizations to voluntary user-pay funded organizations. At the same time the natural world is experiencing dramatic changes, such as the global extinction crisis and widespread loss of biodiversity. User-pay-experience models, such as recreational fishing in North Dakota, are challenged by the uncertainty surrounding angler participation and license sales. Our objectives were to 1) investigate license purchasing dynamics among resident North Dakota recreational anglers to reveal potential angler license typologies, 2) compare trip-related behavior …

A Statistical Fetch Model For Water Wave Glint Correction Using Worldview-3 Imagery, Amanda Jade Quintanilla

Theses and Dissertations

Sun glint in satellite imagery of the water surface contaminates the upwelling signal received by a detector. Many models exist that attempt to correct for this wave facet effect and phenomena. In this work a model for sun glint correction is created using the comparison of image transects between two nearly simultaneously collected images of the same area, although with differing sensor geometry. One image utilized in this research is almost entirely glint free while the other is contaminated by water wave facet glint. Although many models for removing sun glint exist based on various techniques, none are completely accurate, …

Utilization Of Confined Concrete In The Bottom Slab Of Double Composite Box Girder Bridges, Harry Craik

Theses and Dissertations

A mathematical model is proposed for the confinement of rectangular confined reinforced concrete elements under compression. The model was modified from existing models applied to rectangular confined concrete specimens. The present model applies to rectangular reinforced concrete cross-sections with a core aspect ratio of at least 2.0 and a high effective confinement index. The model applies to normal and high-strength concrete and incorporates the spacing of the transverse reinforcing hoops, the strength of the reinforcing bars, the reinforcing quantity, and the core aspect ratio of the section. The proposed model was verified against extensive experimental data, and there was a …

Modelling Terrestrial And Potential Extraterrestrial Photopigments Via Density Functional Theory, Dorothea Illner

Theses and Dissertations

In the search for extraterrestrial life, biosignatures play a crucial role in identifying its putative traces. A commonly known and robust biosignature is the Vegetation Red Edge (VRE), which can be described as a sharp increase of reflectance observed from a planet and stems from the light absorption of photopigments in specific regions in the electromagnetic spectrum. For Earth, this VRE is known to occur around 700 nm, however, if the photopigments absorb light in different regions and have different structures the VRE could experience a wavelenght shift.

In this work, Chlorophyll a and a potential photopigment precursor called Phot0 …

Denoising Diffusion Probabilistic Models Based Accelerated Mri, Alexander Francis Bugielski

Theses and Dissertations

Magnetic Resonance Imaging (MRI) is a cornerstone in obtaining intricate visualizations of anatomy and physiological processes within the human body. However, its extensive scan duration not only causes patient discomfort but also increases the likelihood of motion-induced artifacts in the images. To address such a challenge, this study investigates deep neural network models for reconstructing high-resolution MRI images from noisy and significantly undersampled data in a supervised learning manner. Specifically, it compares three models: a conventional U-Net, a self-attentive U-Net, and an innovative probabilistic diffusion model that builds upon the self-attentive U-Net architecture. These models are evaluated on their ability …

High-Fidelity 3d Reconstruction Of Space Bodies Using Machine Learning And Neural Radiance Fields, Timothy Jacob Huber

Theses and Dissertations

In the era of burgeoning space exploration, the growing population of spacecraft heightens the inevitability of collisions. While traditional imagery remains effective for damage assessment, its lack of 3D representation of the object necessitates more advanced approaches. This research delves into cutting-edge methodologies, with a primary focus on leveraging machine learning and computer vision technologies to enhance the precision and efficiency of damage assessment by taking imagery of a space body and creating a 3D model. The study extensively investigates TransMVSNet, a neural network code employing classical computer vision techniques such as multi-vision stereo (MVS) and depth maps. This approach …

Evaluation Of Beach-Fx — Beach Nourishment Planning Model – Miami Beach Case Study, Brennan Chase Banks

Theses and Dissertations

Miami Beach, located on the Southeast coast of Florida, is a concerning location for coastal erosion because of the increasing intensity and frequency of tropical storms, nuisance flooding, and accelerated sea-level rise due to climate change. Miami Beach is famous for its beautiful beaches, making it a location of high interest for tourists, citizens, and investors. It is vital for coastal practitioners to accurately model coastal processes, beach evolution, and storm damage during the planning stage of coastal protection projects. The U.S. Army Corps of Engineers developed the Beach-fx model as a tool for engineers, planners, and economists to …

Thermal Conductivity Of Thin Porous Ceramic Coatings: An Analytical And Experimental Study, Lei Zhao

Theses and Dissertations

An analytical model of the thermal conductivity of the porous yttrium-stabilized zirconia (YSZ) layer used in the thermal barrier coatings (TBCs) is presented. Such high-temperature resistant coatings are essential to protect the metallic components of gas turbine engines. The model calculates the conductivity based on the coating's porosity, pore size distribution, and pore morphology, including the individual pore cross-section area, aspect ratio, and orientation, which are extracted from the scanning electron microscopy images. The model was verified through comparisons with numerical simulation results from a multiphysics software tool. A laser temperature gradient test was performed to validate the analytical model …

4-Channel Spatially Multiplexed Communication System In Single-Core Optical Fibers, Ce Su

Theses and Dissertations

This dissertation delves into exploring and advancing spatial domain / space division multiplexing (SDM) technologies within single-core optical fibers, a frontier in optical fiber communications poised to meet the burgeoning global demand for data transmission. At the heart of this research is the pursuit to significantly enhance the capacity and efficiency of optical fiber communication systems without necessitating additional fiber infrastructure. This work unveils a new paradigm in optical fiber communications characterized by a pioneering 4-channel SDM system through a meticulous process encompassing theoretical modeling, computational simulations, design innovations, and rigorous experimental validations. Theoretical contributions include the development of refined …

Representation Learning For Generative Models With Applications To Healthcare, Astronautics, And Aviation, Van Minh Nguyen

Theses and Dissertations

This dissertation explores applications of representation learning and generative models to challenges in healthcare, astronautics, and aviation.

The first part investigates the use of Generative Adversarial Networks (GANs) to synthesize realistic electronic health record (EHR) data. An initial attempt at training a GAN on the MIMIC-IV dataset encountered stability and convergence issues, motivating a deeper study of 1-Lipschitz regularization techniques for Auxiliary Classifier GANs (AC-GANs). An extensive ablation study on the CIFAR-10 dataset found that Spectral Normalization is key for AC-GAN stability and performance, while Weight Clipping fails to converge without Spectral Normalization. Analysis of the training dynamics provided further …

Continuous Improvement In North Dakota Schools: Impact Of Mtss Essential Tier 1 Components In Red River Valley Education Cooperative Schools Identified For Targeted Or Comprehensive Support And Improvement, Amy Elizabeth Rohlk

Theses and Dissertations

The goal of the continuous improvement process in North Dakota K-12 education is to review and adjust practice to best support student learning. This study considered the continuous improvement services and supports provided by North Dakota Department of Public Instruction (NDDPI), such as providing training and support through regional education cooperatives, adopting the North Dakota multi-tier system of supports (NDMTSS), identifying criteria for low-performing schools under the targeted or comprehensive support and improvement (TSI or CSI) initiative, as well as partnering with Cognia for program improvement tools and school accreditation reviews.The sample population of this study was limited to member …

A Hybrid Framework To Secure Iot Sensor Networks Based On Blockchain And Machine Learning, Shereen Ismail

Theses and Dissertations

With the advances in sensor network technologies, more and more networked things, or smart objects, are being evolved in cyber-physical-based systems including Internet of Things. In recent years, Internet of Things Sensor Networks is a significant subject to a variety of internal and external cyber-attacks, necessitating the development of robust countermeasures tailored to their unique characteristics and limitations. Various prevention and detection techniques have been proposed to mitigate these attacks. Classical security techniques, such as spread spectrum, cryptography, and key management, may not efficiently detect attacks, and can demand sophisticated software and hardware changes, rendering these solutions insufficient to address …

A Qualitative Case Study Of Students' Of Color Perceptions And Experiences Of Academic Success In College Algebra At Snow College, Melanie Larsen Jenkins

Theses and Dissertations

This qualitative case study explored perceptions of learning support and student success, particularly for students of color who had enrolled in a college algebra course. The purpose of this study was primarily to include student voices in the conversations about student success. The study uses a qualitative case study approach in two ways: 1) to interview nine students who found success and students who did not find success in College Algebra to glean information about their personal experiences and perceptions of learning and 2) to interview three professors of College Algebra to understand their pedagogical strategies that are designed to …

A Study Of Forecasted Electromagnetic Path Errors To Determine Potential Impacts On Detect And Avoid Systems For Unmanned Aircraft, Brianna Marie Kump

Theses and Dissertations

Temperature, atmospheric pressure, and vapor pressure affect electromagnetic propagation. ​For radars, variations in electromagnetic propagation can cause a radar target (e.g., aircraft) to shift in its apparent position, resulting in misrepresentation of the target’s position on the radar display​. These variations can be forecast using atmospheric profiles from Numerical Weather Prediction (NWP) and ray tracing software. Evaluation and quantification of differences between forecasted and analyzed electromagnetic propagation conditions using ray tracing techniques and atmospheric conditions derived from the Rapid Refresh (RAP) model will provide guidance regarding Detect And Avoid (DAA) performance requirements.

Examining The Shared Knowledge And Collaboration When Working With Students With Sensory Disabilities, Lacey Jo Long

Theses and Dissertations

The purpose of this study was to explore the shared knowledge and collaboration between special education and itinerant teachers working with students with sensory disabilities (i.e., teachers of students with visual impairments, teachers of the deaf/hard of hearing, and teachers of students who are deafblind). This study addressed the following research questions: What do special education and itinerant teachers need to know about sensory disabilities? How does this shared knowledge affect the collaboration of special education and itinerant teachers? The study was conducted using an anonymous online survey of special education and itinerant teachers serving students with sensory disabilities, including …

A Statistical Model For The Surface Tension Of Microdroplet Surfactants And Multicomponent Mixtures, Douglas Mohr

Theses and Dissertations

The effects atmospheric aerosols have on climate are not fully understood due to the limited knowledge of the interaction between aerosols and clouds. This interaction, known as the indirect effect of aerosols, is an area of interest within the field of atmospheric science. The presence of surfactants in the atmosphere due to natural and anthropogenic sources is known to negatively affect cloud formation, and is a contributor to the indirect effect. Quantifying how surfactants affect atmospheric aerosols will improve the understanding of the indirect effect. This work explores a statistically mechanically derived surface tension model for surfactant aqueous solutions, which …

Using An Airship Design To Extend A Small Uncrewed Aircraft Flight Endurance, Joseph Reilly

Theses and Dissertations

One limitation of uncrewed aircraft is being unable to fly as long as needed for some operations, such as linear inspection. This research explores the flight endurance of an uncrewed aircraft using airship design. It investigates the benefits of using an airship design to increase the efficiency and extension of the flight of a small, uncrewed aerial system (sUAS). Thus, it is crucial to find ways to augment flight endurance. Two different airframes were built, and flight tested using a lifting gas to provide the lifting force and vectored thrust needed to move. Flight testing captured time in the air …