Digital Commons Network^™

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.

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 …

Ductape: A Steady-State, Axisymmetric Ducted Fan Analysis Code Designed For Gradient-Based Optimization, Judd Mehr, Andrew Ning

Faculty Publications

Electric ducted fans have become an intriguing option for the propulsion systems of clean, quiet advanced air mobility technologies due to their potential benefits in both aerodynamic efficiency and reduced noise profiles compared to open rotor systems. Exploration of conceptual electric ducted fan design in the context of novel, and often complex, applications may be greatly aided by the use of optimization techniques. Specifically, gradient-based optimization lends itself to the exploration of large, complex, multi-disciplinary systems due to its inherent scalability. Despite ducted fans/propellers having been relatively well studied for the last century, modern, gradient-based, optimization-ready analysis tools for ducted …

The Aridification Of The Great Salt Lake, David Thompson

Ballard Brief

Throughout Nepal, brick kilns employ thousands of families annually for the seasonal work of crafting and shipping bricks. As families migrate between work in brick factories and agricultural work at home, more factors block their children from a complete and quality education. The open invitation to begin working with their parents and to help provide for the family becomes a strong temptation that causes many children to give up on school. In addition, Nepal's lack of law enforcement frequently allows children to drop out of school early without consequence. Their parents do not attempt to stop them either, making little …

Geometrically Exact Beam Theory For Gradient-Based Optimization, Taylor Mcdonnell, Andrew Ning

Faculty Publications

Decades of research have progressed geometrically exact beam theory to the point where it is now an invaluable resource for analyzing and modeling highly flexible slender structures. Large-scale optimization using geometrically exact beam theory remains nontrivial, however, due to the inability of gradient-free optimizers to handle large numbers of design variables in a computationally efficient manner and the difficulties associated with obtaining smooth, accurate, and efficiently calculated design sensitivities for gradient-based optimization. To overcome these challenges, this paper presents a finite-element implementation of geometrically exact beam theory which has been developed specifically for gradient-based optimization. A key feature of this …

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 …

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 …

Persevering Through Communication Challenges: A Qualitative Descriptive Exploration Of Communication Experiences In Aphasia, Tyson G. Harmon, Camille Williams, Garrett Cardon, William S. Evans

Faculty Publications

Background

People with aphasia often experience activity limitations and participation restrictions despite wanting to engage in communication activities that are satisfying and meaningful. Communication partner support, the complexity of the communication environment, and the thoughts and feelings of people with aphasia have important implications for both language processing and communicative participation. The perspectives of PWA about the role that environmental and personal factors (e.g. thoughts and feelings) play in their communication experiences could inform clinical practice.

Aims

To qualitatively explore the communication experiences of people with aphasia and how environmental demands and personal factors (especially emotional responses) affect these experiences. …

Cultivating A Digital Environment To Support Primary Source Instruction, Lindsey Memory, Rebecca A. Wiederhold, Abby Beazer, Gregory K. Seppi

Faculty Publications

Primary source literacy continues to be a priority for academic institutions. A growing subtopic is digital primary sources and their unique role in pedagogy. Digital primary sources have the capacity to represent more diverse voices, and their digital nature provides greater accessibility to new and existing user populations who cannot always come to the reading room. Digital primary sources can better meet a variety of needs through ADA-compliant transcription, 24/7 access, portability, and extensibility. With that vision in mind, these projects and materials present their own challenges to archivists, librarians, and other instructors seeking to expand these items’ curricular use. …

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

Journal of Nonprofit Innovation

No abstract provided.

Trust In Information, Preparation, And Resource Adequacy In Coastal Louisiana, Elizabeth Long-Meek, Michael R. Cope, Scott Sanders, Carol Ward

Undergraduate Honors Theses

Natural disasters pose significant challenges to communities, affecting lives, properties, and infrastructure unpredictably. Coastal regions, like those in southern Louisiana, are particularly vulnerable due to their exposure to hurricanes, coastal erosion, and other chronic environmental hazards exacerbated by climate change. This study investigates the relationship between trust in government and social entities and perceptions of disaster preparedness among residents of Plaquemines and Lafourche parishes, Louisiana. Drawing on data collected via a multi-mode survey, including measures of trust and perceived preparedness, logistic regression models reveal that trust in information from federal, state, and local governments, as well as from community networks …

Regional Variations In Nabataean Jewelry, Emily Marie Yankura

Theses and Dissertations

The use of jewelry is just one of many avenues for individual self-expression, but even in the most individualistic society it is also a reflection of certain cultural norms, values, and expectations. This thesis is an analysis of Nabataean jewelry in burial contexts from the three main regions of the ancient kingdom - Medina Selah, the Negev, and Petra – with the aim of reaching a better understanding of Nabataean culture through their jewelry. The types of jewelry, materials used in their construction, and many other variables are compared and reveal unique regional variations within an overall Hellenistic style.

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 …

Women Gaze Back: Affect And Apparatic Disintegration In Funeral Parade Of Roses And Perfect Blue, Jessi Ivie

Theses and Dissertations

This thesis explores how films Funeral Parade of Roses (1969) by Toshio Matsumoto and Perfect Blue (1997) by Satoshi Kon subvert the male gaze of the camera by having the female main characters look back at the audience. The characters Mima (Perfect Blue) and Eddie (Funeral Parade) take control of the camera to subvert the hierarchical relationship between apparatus, audience, and characters. Through the lenses of apparatus and affect theory, these films show how the world of film includes the audience instead of precluding them. Experimental editing and heightened emotional situations unsettle the audience's voyeuristic position, bringing them closer to …

Spatial Patterns In Anthropomorphic Fremont Rock Imagery Of Central Utah, Alyssa Pitts Merrill

Theses and Dissertations

Rock imagery from the late Fremont period (1000-1300 AD) has captivated the interest of both professional and avocational researchers for the past century. In this thesis, I apply a highly systematized method of cataloguing and analysis to 482 anthropomorphs from Clear Creek Canyon (CCC) and Grand Staircase Escalante National Monument (GSENM). The primary theoretical assumption in this thesis is that the shapes used in anthropomorphic imagery convey ideas about how the Fremont saw people. I therefore recorded the head and body morphology and presence of arms, legs, and genitalia of each anthropomorph. By observing the data spatially, I discovered both …

"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 …

The Sound Of Silence: Listening For God In Cormac Mccarthy's The Road, Brittany Higgins Maloy

Theses and Dissertations

In the decimated and silent post-apocalyptic setting of Cormac McCarthy's The Road, the main characters spend a significant amount of time listening to silence, listening for signs of danger, but also listening for the voice of God. Many have discussed the hopeless nihilism juxtaposed with the heavy use of Christian iconography in the novel classifying it within one of these dichotomies or somewhere on the spectrum in between. This paper argues that the hopelessness and stark silence is required to reveal hope and the opportunity to hear God's voice. To demonstrate my argument, I define the characteristics of silence, stillness, …

The Voice As Identity: How Opera Has Influenced Dubbing In Italy And The United States, Brynn Allison Staker

Theses and Dissertations

An enduring Italian tradition of celebrating the voice and the Italian language as seen by the Italian perception and interest in opera has created an environment of celebration for Italian dubbers. The long-established history of opera in Italy, as well as the modern reception of Italian opera, have effectively placed the voice at the forefront of the Italian entertainment industry. This can be seen through an examination of the careers of Italian dubbers and the success that they saw in their industry. The United States did not have a longstanding operatic tradition, and when opera was introduced it was under …

Ip&T 372 Redesign, Christan Hatch-Garcia

Instructional Psychology and Technology Graduate Student Projects

The original proposal for this project was to work with BYU faculty to redesign IP&T 372: Integrating K-12 Educational Technology 2. When my project proposal was approved, IP&T 372 was a fully online course, the second of a three course undergraduate series for pre-service teachers. These courses were designed to prepare students to “effectively use and think with technology to meet current and emergent needs” in elementary and secondary education (Leary 2022). The purposes of the redesign of IP&T 372 were to (1) align the course with IP&T department goals, (2) bring the Canvas design in-line with the most current …

Characterizing The Potential For Failure In Environment Testing Due To Bolted-Joint Friction Nonlinearity And Bilinearity, Brennen Clark

Theses and Dissertations

Nonlinear behavior in systems complicates the analysis and design of many systems in engineering. In vibration engineering, typical methods such as modal analysis fail or require significant adjustment in the presence of nonlinearity. Understanding and modeling nonlinear behavior is becoming more important in many modern engineering applications. One area that is relatively unexplored is how nonlinearity affects environment testing. This can cover a wide variety of subtopics, but this thesis focuses on failures that can occur in a system which are not predicted by corresponding linearized systems. To further limit the scope of this work, and to provide a context …

Parent Involvement Programs And Latinx Families: An Evaluation Of The Parents + Schools = Successful Children Program, Katherine Woods Hancey

Theses and Dissertations

Parent's active involvement in their children's educational experience has been shown to have a positive impact on student outcomes, including academic achievement, attitude toward school, and improved skill-development. There is limited research, however, that explores how best to help parents become more involved in their children's schooling, especially across cultural groups. Currently, there are more than 14.4 million Latinx students in public elementary and secondary schools. Due to the recent increase in Latinx students within the U.S., there is a need to better understand and support Latinx parent involvement in schools. This study evaluated the effectiveness of the Parents + …

Evaluating Computational Predictions Of Magnetic Resonance Acoustic Radiation Force Imaging For Breast Cancer Focused Ultrasound Surgery, Chloe K. Nelson

Theses and Dissertations

Purpose: In magnetic resonance-guided focused ultrasound (MRgFUS) therapies performed in highly heterogeneous tissues such as the breast, the focal location must be located and characterized to guide successful treatments of tumors. Treatment time can be minimized by a priori prediction of the focal location through computational models. The purpose of this work is to evaluate numerical simulations of focused ultrasound (FUS) on their predictions of the focal location. Those simulations are compared to clinical magnetic resonance acoustic radiation force imaging (MR-ARFI) data collected during in vivo treatment of breast tumors. Methods: The focal location was evaluated prior to MRgFUS treatment …

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.