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Designed For Better Control: Using Kinematic And Dynamic Metrics To Optimize Robot Manipulator Design, John R. Morrell Aug 2023

Designed For Better Control: Using Kinematic And Dynamic Metrics To Optimize Robot Manipulator Design, John R. Morrell

Theses and Dissertations

In the field of control theory, optimal performance is generally defined as the best possible controlled performance given a static, unchangeable plant system. However, principled design of the underlying system can make designing effective controllers easier and dramatically improve the final control performance beyond what any finely tuned controller could achieve alone. This work develops performance metrics for serial robot arms which help guide the design and optimization of the structure of the arm to achieve greater final performance. First, a kinematic (motion-based) metric called the Actuator Independence Metric (AIM) measures the uniqueness of the movement capabilities of the different …

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Measuring Microparticle Adhesion Via High-Speed Rotor, Jacob C. Fearnley Aug 2023

Measuring Microparticle Adhesion Via High-Speed Rotor, Jacob C. Fearnley

Theses and Dissertations

Much is known about the atomic/molecular theories that govern adhesion as well as the macroscopic aspects and properties of adhesion. However, adhesion in the microparticle regime is poorly characterized. We report on experiments that use centrifugal force to remove polystyrene (PS) particles from the surface of a high-speed titanium rotor operated in vacuum. This unique rotor can apply forces far greater than other centrifugal force methods or related techniques using atomic force spectroscopy. The mode of attachment, whether particles were located on the windward side versus leeward side of the spinning rotor, time spent in vacuum prior to experiments, and …

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Detailed Characterization Of Material Deformation, Alexander J. Farnsworth Aug 2023

Detailed Characterization Of Material Deformation, Alexander J. Farnsworth

Theses and Dissertations

This dissertation presents a comprehensive exploration of material deformation at the atomic level, investigating key findings and contributions through three fundamental methods: Sum Frequency Generation Spectroscopy (SFG), X-ray Diffraction (XRD), and Electron Backscatter Diffraction (EBSD). The research commences by uncovering the material dependency of nonresonant responses in both SFG and Second Harmonic Generation (SHG) signals. This redefinition of the nonresonant component as an information-rich carrier, rather than mere background noise, leads to novel insights into the potential applications of SFG. The study then delves further into the influence of mechanical stress on materials, establishing a connection between dislocation density on …

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“Já Muito Estropeadas”: Bodies And Landscapes Of Oppression In Rodolfo Teófilo’S A Fome, Mikaela Wood Aug 2023

“Já Muito Estropeadas”: Bodies And Landscapes Of Oppression In Rodolfo Teófilo’S A Fome, Mikaela Wood

Theses and Dissertations

This thesis article analyzes Rodolfo Teófilo's novel "A fome" through the lens of ecofeminism, exploring the representations of gender and nature in Brazilian literature. The novel, set during a devastating drought in the Northeast, follows Manuel de Freitas and his family as they seek relief in Ceará. While existing criticism has focused on the novel's use of nature and masculinity, the portrayal of female characters and the connection between gender and nature representations have been overlooked. Ecofeminist theory offers a critical perspective to understand these dynamics, revealing the devaluation of women and nature in favor of men and human beings …

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Interaction Of Natural Convection And Real Gas Radiation Over A Vertical Flat Plate, Nathan Hale Aug 2023

Interaction Of Natural Convection And Real Gas Radiation Over A Vertical Flat Plate, Nathan Hale

Theses and Dissertations

This study explores natural convection heat transfer and fluid flow from a vertical plate in a radiating gas accounting for real gas spectral behavior. Finite volume techniques are used to solve the coupled nonlinear partial differential equations for mass, momentum, and energy conservation, while radiation transfer is modeled using the Discrete Ordinates finite volume finite angle method. Real gas spectral behavior is accounted for using the Rank Correlated Spectral Line Weighted-sum-of-gray-gases method. It is found that gas temperature and velocity are higher in the boundary layer, thickening the thermal and hydrodynamic boundary layers compared to the limiting case of pure …

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Full Issue Aug 2023

Full Issue

Insights: The Newsletter of the Neal A. Maxwell Institute for Religious Scholarship

No abstract provided.

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Farms Welcomes A New Editor Aug 2023

Farms Welcomes A New Editor

Insights: The Newsletter of the Neal A. Maxwell Institute for Religious Scholarship

Donald L. Brugger joined the FARMS editorial team in November as Editor. A native of southern California, Don received a bachelor's degree in English with a minor in Journalism from Utah State University in 1984. He joined the Church while at USU, then served a mission in Argentina after graduating. He later taught high school English before receiving a master's degree in American Literature from BYU. After working for two years at Deseret Book, Don spent the past five years editing for the Ensign magazine.

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Full Issue Aug 2023

Full Issue

Insights: The Newsletter of the Neal A. Maxwell Institute for Religious Scholarship

No abstract provided.

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Farms Staff Welcomes Newcomers Aug 2023

Farms Staff Welcomes Newcomers

Insights: The Newsletter of the Neal A. Maxwell Institute for Religious Scholarship

Mary Mahan, a recent graduate in English from BYU, joined the FARMS editorial team in August as an assistant editor. An English usage class at BYU sparked Mary's interest in pursuing editing, and she worked several months as an editor for BYU English professor Don Norton before joining FARMS. Mary comes from Centerville, Utah. She enjoys mountain biking, playing the guitar, and listening to the Eagles. We are pleased to have her help with the Foundation's increasing editorial workload.

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Research Opportunities Widen Fund-Raising Focus, Noel B. Reynolds Aug 2023

Research Opportunities Widen Fund-Raising Focus, Noel B. Reynolds

Insights: The Newsletter of the Neal A. Maxwell Institute for Religious Scholarship

We appreciate the interest you have shown and the support you have given to our plans for a new FARMS building. We thought you might like an update on those plans.

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Informal Learning In An Online Book Club: A Qualitative Case Study, Toni E. Pilcher Aug 2023

Informal Learning In An Online Book Club: A Qualitative Case Study, Toni E. Pilcher

Theses and Dissertations

This article examines the online book club called Victober, which is held every October on Youtube and other social media apps. As a qualitive case study, the research uses interviews, observations, and digital documents to explore the interactions and informal learning experiences of four women who participated in Victober 2022. The author identifies five overarching themes that emerged from the data: content creation, community identity, individual identity, rewards, and anticipation. These themes highlight the significance of content creation for YouTube and social media platforms, the sense of community fostered by Victober, the balance between individuality and belonging, the rewards of …

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Interference Between Speaking And Computer Tasks In Younger And Older Adults, Paige Elise Asay Aug 2023

Interference Between Speaking And Computer Tasks In Younger And Older Adults, Paige Elise Asay

Theses and Dissertations

This study examined the effects of computer tasks on speech acoustic measures and the effects of speaking on computer task performance in 30 younger and 30 older adults. Participants completed a speech only task, two computer tasks, and simultaneous speaking and computer tasks. Stimulus sentences included the four corner vowels and two diphthongs embedded between voiceless consonants. Acoustic measures of speech included diphthong transition extent and rate as well as vowel space area (VSA) and vowel articulation index (VAI). A text formatting task included two levels of difficulty. A data entry task included sorting items from a shopping list into …

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Groundwater Resource Assessment For West Africa Using Earth Observations And Groundwater Modeling, Sergio Armando Barbosa Casas Aug 2023

Groundwater Resource Assessment For West Africa Using Earth Observations And Groundwater Modeling, Sergio Armando Barbosa Casas

Theses and Dissertations

Groundwater is a crucial global resource, particularly in semiarid regions where surface water is scarce. As a result, effective groundwater management is essential. However, the challenge lies in a lack of data and information for proper decision-making. This dissertation present studies related to groundwater storage changes and recharge in West Africa, using data from NASA's Gravity Recovery and Climate Experiment (GRACE) mission. In Niger, this research reveals little change in groundwater storage from 2002 to 2010 but a steep rise from 2010 to 2021, attributed partially to increased precipitation. Groundwater resources in Niger are found to be underutilized, with estimated …

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Taxonomic Revision And Phylogenetic Analysis Of The Philadelphicus Group In The Genus Proctacanthus (Insecta: Diptera: Asilidae), And Key To All Proctacanthus North Of Mexico, Teagan Marie Mulford Aug 2023

Taxonomic Revision And Phylogenetic Analysis Of The Philadelphicus Group In The Genus Proctacanthus (Insecta: Diptera: Asilidae), And Key To All Proctacanthus North Of Mexico, Teagan Marie Mulford

Theses and Dissertations

Proctacanthus (Macquart 1838), an elegant genus of robber flies within the Asilidae family, plays a significant ecological and economic role. However, the lack of a comprehensive taxonomic treatment hinders their identification and thus their use in evolutionary and behavioral research. This study focuses on the taxonomic revision of the Proctacanthus, identifying the features used in recognizing the philadelphicus Species Group and the rufiventris Species Group. By providing systematic and biological data, describing new species, and offering a key for identification, this research contributes to understanding the ecological significance and geographic distribution and history of Proctacanthus. This work will enhance future …

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Feasibility Of Rna-Based Pathogen Detection In An Infant Formula Matrix, Gweneth Claire Gustafson Aug 2023

Feasibility Of Rna-Based Pathogen Detection In An Infant Formula Matrix, Gweneth Claire Gustafson

Theses and Dissertations

Background: The dairy processing industry is currently hindered by slow, antiquated testing for high-risk pathogens, including Listeria monocytogenes and Cronobacter sakazakii. Powder infant formula's low water activity and substantial fat content enhance the survival and thermotolerance of such foodborne pathogens. As DNA-based detection methods can produce false positives even after cell death, a more accurate approach is needed. The objective of this study is to evaluate the suitability of an RNA-based platform for the detection of pathogens in a dairy powder matrix. Materials and Methods: A unique phenol-chloroform extraction method was used to obtain total RNA from heat-killed and unheated …

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Separation Of Perrhenate And Perfluoroalkyl Substances By Ion Chromatography With Customized Stationary Phases, Wai Ning Chan Aug 2023

Separation Of Perrhenate And Perfluoroalkyl Substances By Ion Chromatography With Customized Stationary Phases, Wai Ning Chan

Theses and Dissertations

Ion exchange chromatography (IC) is an analytical technique used to separate charged molecules including ions, proteins, small nucleotides, and amino acids. It can function in anion or cation mode. In this dissertation, anion exchange chromatography was used, and column materials were made in our lab with resorcinarene-based compounds called cavitands. Cavitands create cavities to bind to molecules because of their three-dimensional structure. Two new gradient IC methods were established to identify and quantify perrhenate and perfluoroalkyl substances (PFAS) by customized resorcinarene-based column, zinc cyclen resoecinarene (ZCR) and arginine methyl ester (RUE) columns. The ZCR column accomplished outstanding separation of perrhenate …

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The Role Of Cytosolic Chaperonin Cct And Its Co-Chaperone Phlp1 In Folding And Assembly Of Signaling Complexes, Yujin Kwon Aug 2023

The Role Of Cytosolic Chaperonin Cct And Its Co-Chaperone Phlp1 In Folding And Assembly Of Signaling Complexes, Yujin Kwon

Theses and Dissertations

CCT, a large (1 MDa) protein-folding machine, is a eukaryotic group II chaperonin that is essential for folding many cellular proteins and is the most complex of all chaperonins with two rings each composed of eight paralogous subunits. CCT captures proteins in its folding chamber to assist the folding of its substrates. CCT utilizes ATP hydrolysis to open and close its chamber and fold its substrates. CCT has been shown to be important in the folding of proteins with - propeller domains which consist of seven WD40 repeat sequences that fold into -sheets that form the blades of a propeller-like …

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Evaluating And Advancing Automated Traffic Signal Performance Measures: Statistical And Machine Learning Approaches, Bangyu Wang Aug 2023

Evaluating And Advancing Automated Traffic Signal Performance Measures: Statistical And Machine Learning Approaches, Bangyu Wang

Theses and Dissertations

Automated traffic signal performance measures (ATSPM) are increasingly used to collect and evaluate traffic data from signalized intersections. ATSPM provide invaluable insights into both current and historical traffic signal performance. With their adoption by over 39 state and local transportation agencies, ATSPM play a crucial role in traffic operation and maintenance. ATSPM are continually evolving, introducing new performance measures and applications tailored to the needs of various transportation agencies. However, despite their potential, several challenges require attention and resolution. The first challenge involves the underutilization of ATSPM data due to its massive volume, which can overwhelm traditional identification and prioritization …

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Perceptions Of Teacher Self-Efficacy For A Fourth Year Teacher: A Self-Study Approach, Alyssa Crabb Aug 2023

Perceptions Of Teacher Self-Efficacy For A Fourth Year Teacher: A Self-Study Approach, Alyssa Crabb

Theses and Dissertations

Teacher self-efficacy is a well-researched concept and a key component in student achievement, teacher performance, motivation, and retention. This self-study examined the perceptions of a fourth-year teacher's sense of self-efficacy in her classroom. The study was conducted by journaling about daily events that influenced the teacher's sense of doing well or not over the course of the first term of a school year (August–December). Weekly journals were then re-storied using a three-dimensional narrative structure to ground deeper into the context of the experience of being a teacher. Two main themes emerged: concern for students and concern for evaluation from other …

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Rural Science Teachers Social Network Analysis Matrices, Rebecca L. Sansom, Tracy Poulsen Aug 2023

Rural Science Teachers Social Network Analysis Matrices, Rebecca L. Sansom, Tracy Poulsen

ScholarsArchive Data

These are the social network matrices for our study of rural science teachers. Each matrix is located on a separate tab on the spreadsheet.

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Critical Engagements With Award Winning Picturebooks: My Journey In Creating A More Equitable Classroom Library, Carrie Elizabeth Crowe Aug 2023

Critical Engagements With Award Winning Picturebooks: My Journey In Creating A More Equitable Classroom Library, Carrie Elizabeth Crowe

Theses and Dissertations

Research consistently shows that students from historically marginalized populations have difficulty accessing texts that represent the realities of their lives. Concerned that such might be the case for my students, I conducted an inventory of my classroom library and sought out award-winning texts that could make my library more diverse and inclusive. I then analyzed these award-winning texts using Bishop's (1992) categories of multicultural literature in order to better understand the picturebooks' underlying messages and ideologies. My examinations showed that the majority of the texts fit into the same category (culturally specific), though I was able to identify award-winning texts …

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Terahertz From Electrons, Electronics From Terahertz, Clayton D. Moss Aug 2023

Terahertz From Electrons, Electronics From Terahertz, Clayton D. Moss

Theses and Dissertations

Time-domain terahertz spectroscopy (THz-TDS) is a valuable technique for studying collective ultrafast phenomena. Several mechanisms exist for converting ultrashort optical laser pulses into coherent THz sources. Broadband THz pulses can be obtained from electron currents in air plasma, which requires combinations of different colors of light to be most effective. I report multi-color generation schemes of THz pulses that deliver coherent THz output. Experimental and theoretical work using the photocurrent model describe ways to use non-harmonic color combinations to utilize several sources of light available in a table-top laser setup. Additionally, THz-TDS is used to study a variety of ultrafast …

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Robust Localization And Landing For Autonomous Unmanned Aerial Vehicles In Maritime Environments, Alexander D. Jordan Aug 2023

Robust Localization And Landing For Autonomous Unmanned Aerial Vehicles In Maritime Environments, Alexander D. Jordan

Theses and Dissertations

This thesis presents methods for robust precision landing of unmanned air vehicles (UAVs) on platforms at sea. Localization methods are proposed for UAV-to-boat state estimation for systems that employ real- time kinematic (RTK) global navigation satellite system (GNSS) and vision sensors. Solutions for GNSS-only are first presented, followed by the fusion of GNSS and vision. The important problem of sensor intrinsic calibration is solved with a novel offline batch estimation approach. Hardware results are presented for all methods. Our calibration of GNSS-to-camera is shown to estimate sensor offsets with millimeter level accuracy. Localization systems are combined with custom state machines …

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The Influence Of Political Media On Large Language Models: Impacts On Information Synthesis, Reasoning, And Demographic Representation, Alexander Glenn Shaw Aug 2023

The Influence Of Political Media On Large Language Models: Impacts On Information Synthesis, Reasoning, And Demographic Representation, Alexander Glenn Shaw

Theses and Dissertations

This thesis investigates the impact of finetuning the LLaMA 33B language model on partisan news datasets, revealing negligible changes and underscoring the enduring influence of pretraining datasets on model opinions. Training nine models across nine distinct news datasets spanning three topics and two ideologies, the study found consistent demographic representation, predominantly favoring liberal, college-educated, high-income, and non-religious demographics. Interestingly, a depolarizing effect emerged from partisan news finetuning, suggesting that intense exposure to topic-specific information might lead to depolarization, irrespective of ideological alignment. Despite the exposure to contrasting viewpoints, LLaMA 33B maintained its common sense reasoning ability, showing minimal variance on …

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Full Issue Aug 2023

Full Issue

Insights: The Newsletter of the Neal A. Maxwell Institute for Religious Scholarship

No abstract provided.

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Two Notes On The Lord's Prayer, John W. Welch Aug 2023

Two Notes On The Lord's Prayer, John W. Welch

Insights: The Newsletter of the Neal A. Maxwell Institute for Religious Scholarship

Four versions of the Lord's Prayer are found in scripture, in Matthew 6, JST Matthew 6, Luke 11, and 3 Nephi 13. Recent research enhances our appreciation of the words that Jesus chose to use.

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Early Life Drift And Environmental Effects In Nanocomposite Sensors For Biomechanics Applications, Jacob D. Carter Aug 2023

Early Life Drift And Environmental Effects In Nanocomposite Sensors For Biomechanics Applications, Jacob D. Carter

Theses and Dissertations

Wearable nanocomposite strain sensors are a promising technological advancement for real-time monitoring of human biomechanics. However, characterization of these sensors for biomechanical use can be complex due to factors such as creep-related resistance drift and environmental influence (humidity and temperature). The purpose of this work is to investigate and quantify these factors as well as seek to mitigate their effects. The first portion of this thesis is a study on creep-related drift of the electrical behavior of the sensors, investigating the impact of material cure levels and application of a compressive prestrain in ameliorating the observed drift. DSC testing of …

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The Connection Between Linguistic Insecurity And Cultural Identity In Spanish Heritage Language Learners, Sara Nicole Gardner Aug 2023

The Connection Between Linguistic Insecurity And Cultural Identity In Spanish Heritage Language Learners, Sara Nicole Gardner

Theses and Dissertations

The United States is a host to several ethnicities that bring both their own languages and their own culture to an already large mixing pot. The children of the immigrants who grow up learning both English and their families' heritage language are called heritage language learners (HLLs). The first objective of the study was to find out whether foreign language anxiety had a relationship with reading and writing in Spanish for HLLs in high school. The second was to ascertain whether perception of ethnic identity also had a relationship with reading and writing in Spanish for heritage language learners in …

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Spatiotemporal Variation Of Alfalfa Leaf Area Index And Crop Water Productivity In An Irrigated Alfalfa Field, Keegan Dillon Hammond Aug 2023

Spatiotemporal Variation Of Alfalfa Leaf Area Index And Crop Water Productivity In An Irrigated Alfalfa Field, Keegan Dillon Hammond

Theses and Dissertations

Throughout the world, there continues to be increasing demand for freshwater resources. With urban expansion, increased demand from a growing population, drought, and climate change, growers must produce more crops using less water. One approach to water conservation is with a variable rate irrigation (VRI) system. VRI technology allows growers to irrigate crops according to site-specific within-field variation instead of a uniform rate across the field. This thesis addresses aspects of within-field variation of irrigated alfalfa as it relates to the potential for VRI. Chapter 1 examines measurement of within-field variation of leaf area index (LAI) to inform variable-rate irrigation …

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Investigating How And Why Students Pay Attention And Engage In A High School German Level One Class, Lindsey Marie Nielson Aug 2023

Investigating How And Why Students Pay Attention And Engage In A High School German Level One Class, Lindsey Marie Nielson

Theses and Dissertations

This qualitative study investigates how and why students pay attention and engage in a German Level One class in a public high school in Utah. Data were collected from surveys, classroom observations, video/audio recordings, and interviews. Findings indicate that three major factors influenced student engagement during this study-type of motivation (extrinsic or intrinsic), type of learning activity (individual, partner, or class), and the mode of activity (technology, paper, or speaking). Additional findings offer support for the idea that metacognition may enhance language learning.

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