Digital Commons Network^™

Effect Of Local Chain Stiffness On Oligomer Crystallization From A Melt, Pierre Kawak, Christopher Akiki, Douglas R. Tree

Faculty Publications

While the process by which a polymer crystal nucleates from the melt has been extensively studied via molecular simulation, differences in polymer models and simulated crystallization conditions have led to seemingly contradictory results. We make steps to resolve this controversy by computing low-temperature phase diagrams of oligomer melts using Wang-Landau Monte Carlo simulations. Two qualitatively different crystallization mechanisms are possible depending on the local bending stiffness potential. Polymers with a discrete bending potential crystallize via a single-step mechanism, whereas polymers with a continuous bending potential can crystallize via a two-step mechanism that includes an intermediate nematic phase. Other model differences …

An Information Geometric Analysis Of A Shallow-Water Waveguide Using Vgs Parametrization, Michelle Wang

Undergraduate Honors Theses

In geoacoustic inversion, selecting an appropriate seabed parametrization, especially with an unknown number of sediment layers, is a challenge that is compounded by potential bias when establishing bounds in the parameter search space. One approach to addressing these issues is rooted in the techniques of Information geometry. Information geometry informs model selection and parameterization by quantifying which model parameters are informed by observational data. This paper provides an information geometric analysis of a shallow-water waveguide, where the acoustic properties of the lower half-space are derived from the viscous grain-shearing (VGS) model.

Specifically, we consider single-frequency transmission loss (TL) across a …

Membrane Hinges For Deployable Systems, C. Mitchel Skinner

Theses and Dissertations

Origami-inspired and deployable technology has become increasingly common in a variety of applications including satellite and antenna designs for space applications. The drive to utilize ultra-thin materials in the design of these deployable space structures has led to the development of membrane hinges. Membrane hinges show promise as an effective surrogate fold because of their potential advantages including requiring minimal volume and mass, allowing for small bending radii, and functioning without lubricant. Two challenges associated with membrane hinges include reliability after repeated cyclic loading and predictability of a large deployable with radially-unconstrained membrane hinges. The research presented includes the cyclic …

Rigorous Verification Of Stability Of Ideal Gas Layers, Damian Anderson

Theses and Dissertations

In this thesis we develop tools for carrying out computer assisted proof of the stability of traveling wave solutions of the spatially one-dimensional compressible Navier-Stokes equations with an ideal gas equation of state. In particular, we obtain rigorous, tight error bounds on a high-accuracy numerical approximation of the traveling wave profile for parameters corresponding to air, and we obtain rigorous representations in a neighborhood of positive and negative infinity of the solution to the first order ODE associated with linearizing the PDE equations about the traveling wave solution. We also develop supporting tools for rigorous verification of wave stability.

Characteristics Of Pyrolysis Products Of California Chaparral And Their Potential Effect On Wildland Fires, Mahsa Alizadeh, David R. Weise, Thomas H. Fletcher

Faculty Publications

The aim of this study was to investigate the pyrolysis of selected California foliage and estimate the energy content of the released volatiles to show the significance of the pyrolysis of foliage and its role during wildland fires. While the majority of the volatiles released during the pyrolysis of foliage later combust and promote fire propagation, studies on the energy released from combustion of these compounds are scarce. Samples of chamise (Adenostoma fasciculatum), Eastwood’s manzanita (Arctostaphylos glandulosa), scrub oak (Quercus berberidifolia), hoaryleaf ceanothus (Ceanothus crassifolius), all native to southern California, and sparkleberry …

Derivative Propagation Through Vortex Particle Method Simulation, Eric Green, Andrew Ning

Faculty Publications

Automatic differentiation (AD) is a powerful tool for evaluating numerical derivatives. In particular, reverse-mode AD provides numerical gradients in a way that is insensitive to the number of input variables. This makes reverse-mode AD well-suited for solving large optimization problems. However, reverse-mode AD has a particularly large associated memory cost because most intermediate values in operations need to be cached. This is problematic for large problems such as aerodynamics simulations, though, since the memory requirements can quickly become impractical. The solution implemented in this work is to provide analytic pullback expressions for functions for which many of the intermediate values …

Trajectory Optimization Of Evtol And Conventional Aircraft: A Comparative Analysis Of Vortex Particle Method And Vortex Lattice + Blade Element Momentum Theory, Andrew Tagg, Ryan Anderson, Cibin Joseph, Andrew Ning

Faculty Publications

Trajectory optimization of aircraft transition maneuvers can significantly influence the design of these systems, particularly when making decisions about aircraft geometry, propulsion sizing, and control system design. This paper presents the trajectory optimization of air vehicles including electric vertical takeoff and landing (eVTOL) as well as conventional aircraft. The study evaluates the influence of fidelity in trajectory design by comparing the use of two aerodynamic methods in the context of trajectory optimization. The mid-fidelity method utilizes a vortex lattice method (VLM) to model lifting surfaces while employing blade element momentum theory (BEMT) to model rudimentary rotor-wing interactions. The high-fidelity approach …

Solving Unsteady Potential Flow Problems In O(N) Time, Ryan Anderson, Andrew Ning

Faculty Publications

Design of vertical takeoff and landing aircraft is challenging in part due to significant aerodynamic interactions between rotors and wings. Computational models can aid in their design, but are computationally expensive. 3-D panel methods coupled with vortex particle wakes offer an attractive solution, but solving for the panel strengths scales poorly for large problems. Multigrid methods, such as Krylov subspace methods in conjunction with the fast multipole method (FMM), have been demonstrated to reduce the scaling to O(𝑁). We explore the performance and limitations of the Krylov-FMM method, traditional matrix-powered GMRES, LU decomposition, and a novel O(𝑁) multigrid approach to …

Addressing Social Inequalities Using Ai, Big Data, And Machine Learning, Erica L. Jensen, Lakell Archer, Sumaya Ali

Journal of Nonprofit Innovation

No abstract provided.

Application And Development Of Ceragenins In Medical Device Coatings For Clinical Settings, Elliot E. Sherren

Theses and Dissertations

Hospital-acquired infections (HAIs) pose a significant and increasing threat to global health. One primary cause of this threat is increasing antibiotic resistance. As traditional antibiotics continue to grow less effective, there is an urgent need for novel antimicrobial strategies. This work explores the potential of ceragenins, also known as cationic steroid antimicrobials (CSAs), as a promising alternative to combat HAIs. Specifically, we investigated potential roles that CSAs can play in the context of multiple medical device coatings in healthcare settings. Ceragenins are synthetic mimic of antimicrobial peptides (AMPs) which exhibit broad-spectrum antimicrobial activity against many common pathogens that have been …

Exploring Seizure Signal Processing And Methods To Characterize Seizure-Like Activity In Mouse Brains, Benjamin Kearsley

Undergraduate Honors Theses

Status Epilepticus (SE) is a dangerous type of seizure that is difficult to treat and can have permanent or fatal consequences. Developing methods to properly process and classify SE in Local Field Potential (LFP) signals are important steps towards being able to predict SE in clinic and save lives. This thesis explores methods for the seizure data processing LFP data with the goal of gaining a deeper understanding of the effect of brain region and tissue preparation paradigm on power output in specific frequency ranges. The brain regions compared are the neocortex and hippocampus, and the preparation paradigms are 4AP …

Elucidating The Role Of Aging In Protein Misfolding And Amyloid Cascade In Transthyretin Amyloidosis, Chad Hyer

Undergraduate Honors Theses

This study attempts to provide the first comprehensive proteomic analysis of protein folding stability (PFS) in transthyretin amyloidosis (ATTR) across different age groups to shed light on the mechanisms of age-mediated protein misfolding and the amyloid cascade. Utilizing the Iodine Protein Stability Assay (IPSA), we characterize the PFS of proteins across the serum proteome in a cohort of 100 individuals (18-85 years old) to investigate the impact of aging on changes in protein folding across the proteome. Presented are preliminary data from 20 participants.

Our study overcomes limitations in previous studies of ATTR by providing a structural perspective on TTR …

Synthesis Of Streptococcus Pneumoniae Serotypes 6a And 6b Di- And Trisaccharides As Propargyl Glycosyl Antigens For Glycoconjugate Vaccines, Tianyao Meng

Theses and Dissertations

Streptococcus pneumoniae (Spn) is a globally prevalent Gram-positive pathogen responsible for invasive pneumococcal diseases (IPD). Among its over 90 serotypes, Spn serotypes 6A (Sp6A) and 6B (Sp6B) are two of the most common causes of IPD around the world and are more frequently isolated from infections than most of the other serotypes. Our group has previously developed a method for making immune responses to bacterial glycans T cell-dependent, involving attachment of short synthetic glycans to a virus-like nanoparticle (VLP), and in combination with a natural killer T cell (NKT cell) adjuvant. This strategy enhanced immune responses by facilitating T cell …

A Nordhaus-Gaddum Type Problem For The Normalized Laplacian Spectrum And Graph Cheeger Constant, Adam Widtsoe Knudson

Theses and Dissertations

We will study various quantities related to connectivity of a graph. To this end, we look at Nordhaus-Gaddum type problems, which are problems where the same quantity is studied for a graph $G$ and its complement $G^c$ at the same time. For a graph $G$ on $n$ vertices with normalized Laplacian eigenvalues $0 = \lambda_1(G) \leq \lambda_2(G) \leq \cdots \leq \lambda_n(G)$ and graph complement $G^c$, we prove that \begin{equation*} \max\{\lambda_2(G),\lambda_2(G^c)\}\geq \frac{2}{n^2}. \end{equation*} We do this by way of lower bounding $\max\{i(G), i(G^c)\}$ and $\max\{h(G), h(G^c)\}$ where $i(G)$ and $h(G)$ denote the isoperimetric number and Cheeger constant of $G$, respectively. We …

Jinetes De La Tormenta: The Invasive Influence Of Gender Constructs On The Journey Towards Selfhood And Societal Progress, Marissa Nicole Luquette

Theses and Dissertations

The novel Jinetes de la tormenta, written by Spanish author, Javier Castañeda de la Torre, presents gender as an obstacle to individuals in the ongoing process of self-discovery (as it relates to personal identity) and as the underlying source of human discontent in the technological age. Jinetes represents gender as a hindrance to the developing self through masculine and feminine binaries in European colonial languages and through the performative behavioral expectations tethered to the gendered body the theoretical works of Jacques Lacan and Hélène Cixous. The theoretical works of Jacques Lacan and Hélène Cixous establish the argument surrounding linguistic gender …

"Vampire Plastics": An Investigation Of Poly(Olefin Sulfone) Depolymerization And Its Dust Mitigation Abilities, Alexandra Kathryn Kanani Gallion Stapley

Theses and Dissertations

The ubiquity of particulate contamination requires dust mitigation techniques to provide low-scatter surfaces and edges on sensitive optical devices in space. Poly(olefin sulfone)s have been shown to photodegrade with the assistance of a photobase generator when exposed to UV light (254 nm) and heat (120 °C). These polymers may be useful for minimizing dust on optical surfaces for space applications. However, their behavior in vacuum has not been fully characterized. We synthesized poly(2-methyl-1-pentene sulfone) (PMPS) and poly(1-hexene sulfone) (PHS) with and without a photobase generator. We studied the photodegradation (172 nm or 254 nm) of thin films in vacuum. Spectroscopic …

The Osteological Neutral Pose Of The Neck Of An Apatosaurine Sauropod Based On Virtual And Physical Models, Colin Don Boisvert

Theses and Dissertations

An array of sauropod taxa coexisted in Late Jurassic North America. How so many giant genera coexisted without competing for food is puzzling considering their potential metabolic requirements. One aspect of this question is neck posture, which has been much contested, both in terms of the intrinsic curvature of the neck and the resultant elevation of the head. Neck curvature is characterized by the Osteological Neutral Pose (ONP), wherein the intervertebral joints are in an undeflected state. This pose is crucial to understanding neck posture. The articulated series of presacral vertebrae 2-19 of an exceptionally well-preserved apatosaurine, BYU 18531, are …

Procedural Pre-Training For Visual Recognition, Connor S. Anderson

Theses and Dissertations

Deep learning models can perform many tasks very capably, provided they are trained correctly. Usually, this requires a large amount of data. Pre-training refers to a process of creating a strong initial model by first training it on a large-scale dataset. Such a model can then be adapted to many different tasks, while only requiring a comparatively small amount of task-specific training data. Pre-training is the standard approach in most computer vision scenarios, but it's not without drawbacks. Aside from the cost and effort involved in collecting large pre-training datasets, such data may also contain unwanted biases, violations of privacy, …

Zeros Of Convex Combinations Of Elementary Families Of Harmonic Functions, Rebekah Ottinger

Theses and Dissertations

Brilleslyper et al. analyzed a one-parameter family of harmonic trinomials, and Brooks and Lee analyzed a one-parameter family of harmonic functions with poles. Each family was explored to find the relationship between the size of the parameter and the number of zeros of the harmonic function. In this thesis, we examine convex combinations of members of these families. We determine conditions under which the critical curves separating the sense-preserving and sense-reversing regions are circular. We show that the number of zeros of a convex combination can be greater than the maximum number of zeros of either part.

Ocean Rain Detection And Wind Retrieval Through Deep Learning Architectures On Advanced Scatterometer Data, Matthew Yoshinori Otani Mckinney

Theses and Dissertations

The Advanced Scatterometer (ASCAT) is a satellite-based remote sensing instrument designed for measuring wind speed and direction over the Earth's oceans. This thesis aims to expand and improve the capabilities of ASCAT by adding rain detection and advancing wind retrieval. Additionally, this expansion to ASCAT serves as evidence of Artificial Intelligence (AI) techniques learning both novel and traditional methods in remote sensing. I apply semantic segmentation to ASCAT measurements to detect rain over the oceans, enhancing capabilities to monitor global precipitation. I use two common neural network architectures and train them on measurements from the Tropical Rainfall Measuring Mission (TRMM) …

Leveraging Biological Mechanisms In Machine Learning, Kyle J. Rogers

Theses and Dissertations

This thesis integrates biologically-inspired mechanisms into machine learning to develop novel tuning algorithms, gradient abstractions for depth-wise parallelism, and an original bias neuron design. We introduce neuromodulatory tuning, which uses neurotransmitter-inspired bias adjustments to enhance transfer learning in spiking and non-spiking neural networks, significantly reducing parameter usage while maintaining performance. Additionally, we propose a novel approach that decouples the backward pass of backpropagation using layer abstractions, inspired by feedback loops in biological systems, enabling depth-wise training parallelization. We further extend neuromodulatory tuning by designing spiking bias neurons that mimic dopamine neuron mechanisms, leading to the development of volumetric tuning. This …

Medial Temporal Lobe Surface Features And Cognition In Aging Amyloid-Positive Individuals, Jacob Johnston

Undergraduate Honors Theses

Memory consolidation and metabolism are known to differ between amyloid-beta plaque positive (A+) and negative (A-) amnestic Mild Cognitive Impairment (aMCI) and Alzheimer's disease (AD) dementia participants despite similar medial temporal lobe (MTL) volume between groups. Using high-dimensional surface analysis (shape characterization), this study identified structural differences in the medial temporal lobe between A+ aMCI, A+ AD dementia, and amyloid-negative (A-) healthy control groups (CON), specifically in the CA1 and subiculum regions of the hippocampus and entorhinal cortex. Additionally, regional brain surface-based features were correlated with procedural and episodic memory measures, finding positive associations between CA1 integrity and episodic memory …

Investigation Of Collision Cross Sections & Time-Resolved Structural Modification Of Biomolecules, Host-Guest Systems, & Small Molecules Using Ion Mobility & Fourier Transform Ion Cyclotron Resonance Mass Spectrometry, Noah Mismash

Theses and Dissertations

This thesis explores the structures and structural changes of supramolecular host-guest systems, proteins, and other small molecules in the gas phase, utilizing a combination of computational modeling and experimental data. The primary instruments employed were a Fourier transform ion cyclotron resonance mass spectrometer (FTICR-MS) and an ion mobility mass spectrometer (IM-MS). In the IM-MS experiments, the focus was on investigating the binding behavior of cyclodextrin macrocycles—specifically α, β, and γ-cyclodextrin—with per-fluoroalkane substances (PFAS), which are pervasive environmental contaminants. This investigation involved measuring ion-neutral collision cross sections and using computational modeling to determine whether PFAS compounds bind inside or outside the …

A Study Of Professional Learning Community Leadership Using A Modified Approach, Makayla Willis Needs

Theses and Dissertations

Professional Learning Communities (PLCs) are an important vehicle for teacher reflection and collaboration. The team leader of the PLC plays a critical role in the effectiveness of a PLC in improving instruction and student learning. However, there is less research around how the team leader facilitates the work of the PLC to improve instruction. This paper reports on a self-study investigation conducted by the team leader who used a modified approach to the PLC process focused on student mathematical thinking. The self-study consisted of analyzing video conversations of three PLC meetings to understand the nature of the leadership and how …

Mathematical Modeling And Understanding The Physiological Mechanisms Of Vibration On Wound Healing And Scar Remodeling, Devin Rion Needs

Theses and Dissertations

Chronic wounds and pathological scars reduce the quality of life for millions of people worldwide. Through mathematical modeling and clinical testing, understanding of how these conditions occur continues to increase. These tools have also been employed to investigate the efficacy of treatments that could impact wound healing and scar remodeling. The purpose of this work is to investigate the physiological effects of vibration treatment on wound healing, blood flow, and scar remodeling through mathematical modeling and experimental testing. This work presents and validates a mathematical murine model for whole body vibration enhanced wound healing (VEWH). This VEWH model builds on …

Control, Localization, And Shock Optimization Of Icosahedral Tensegrity Systems, Brett Layer

Theses and Dissertations

Exploring the design space of tensegrity systems is the basis of the work presented in this thesis. The areas explored as part of this research include the optimization of tensegrity structures to minimize the size of a tensegrity structure given payload shock constraints, and the control and locomotion of an icosahedral tensegrity system using movable masses and using an accelerometer in conjunction with leveraging geometrical knowledge of an icosahedral tensegrity system to localize the system after the system moves. In the optimization design space, a simplified model was created to represent an icosahedral tensegrity structure. This was done by assuming …

Epck Transfer Between Math And Science, Elise Marie Joyner

Theses and Dissertations

Generalist elementary school teachers have little time to develop enacted pedagogical content knowledge (ePCK) in all content areas. Therefore, the transfer of ePCK from one content area to another, such as between math and science, can help generalist teachers build their knowledge needed for teaching regardless of their content area strengths. This self-study examines the ePCK components and their elements present in both math and science instruction. I am a fifth-grade teacher in Utah County who has been teaching for 4 years. Math is taught daily, and science is taught approximately three times a week. The self-study includes six video …

Identifying Barriers To Sustainability Of Dual Language Immersion Programs In Utah Schools, Jennifer Leigh Rowley

Theses and Dissertations

Dual Language Immersion (DLI) educational programming began in Utah in 2008. Within three short years, DLI programs in Utah schools had grown from 5 to 58 programs statewide. Presently, Utah now has over 301 DLI programs, including instruction in Spanish, Chinese, French, Portuguese, Russian, and German. DLI programs have many benefits and have attracted many student families. However, not much research has been done on program planning, implementation, and the sustainability of DLI programs within individual school cultures and climates. This study will examine the satisfaction level of faculty, staff, administrators, and parents at DLI schools (including how supported/understood each …

Foam Fraction Flow: Using Mls-Mpm With Volume Fractions To Simulate Low-Density Dry Foam, Alexander Neville

Theses and Dissertations

Foaming bubbles are a common element seen throughout both nature and man-made civilization. All types of bubbles behave variably. For example, foams float in water, splash out from buckets, and are squeezed out of hand soap dispensers. Due to their complexity and variance in behavior, they can be expensive to simulate and difficult to portray realistically. When simulating dense concentrations of bubbles with little free-flowing water, such as soap films, three variables need to be accounted for: how the fluid will move, how the bubbles will be sized, and how the bubbles will behave when they come into contact with …

Minimal Specialization: The Coevolution Of Network Structure And Dynamics, Annika King

Theses and Dissertations

The changing topology of a network is driven by the need to maintain or optimize network function. As this function is often related to moving quantities such as traffic, information, etc., efficiently through the network, the structure of the network and the dynamics on the network directly depend on the other. To model this interplay of network structure and dynamics we use the dynamics on the network, or the dynamical processes the network models, to influence the dynamics of the network structure, i.e., to determine where and when to modify the network structure. We model the dynamics on the network …