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Full-Text Articles in Physical Sciences and Mathematics

Sequence Biostratigraphy Of Carboniferous-Permian Boundary Strata In Western Utah: Deciphering Eustatic And Tectonic Controls On Sedimentation In The Antler-Sonoma Distal Foreland Basin, Joshua Kerst Meibos Jul 2019

Sequence Biostratigraphy Of Carboniferous-Permian Boundary Strata In Western Utah: Deciphering Eustatic And Tectonic Controls On Sedimentation In The Antler-Sonoma Distal Foreland Basin, Joshua Kerst Meibos

Theses and Dissertations

The stratal architecture of the upper Ely Limestone and Mormon Gap Formation (Pennsylvanian-early Permian) in western Utah reflects the interaction of icehouse sea-level change and tectonic activity in the distal Antler-Sonoma foreland basin. Eighteen physically and biostratigraphically corelated stratigraphic sections provide a database for tracing Permo-Carboniferous boundary strata over a north-south distance of 60 km. These formations comprise 14 unconformity-bounded depositional sequence: three in the upper Ely (UE1-UE3) and 11 in the Mormon Gap Formation (MG1-MG11). Conodont and fusulinid faunas provide precise biostratigraphic information for a number of parasequences in the upper Ely and Mormon Gap formations. This paleontological information …

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Hyperparameters For Dense Neural Networks, Christopher James Hettinger Jul 2019

Hyperparameters For Dense Neural Networks, Christopher James Hettinger

Theses and Dissertations

Neural networks can perform an incredible array of complex tasks, but successfully training a network is difficult because it requires us to minimize a function about which we know very little. In practice, developing a good model requires both intuition and a lot of guess-and-check. In this dissertation, we study a type of fully-connected neural network that improves on standard rectifier networks while retaining their useful properties. We then examine this type of network and its loss function from a probabilistic perspective. This analysis leads to a new rule for parameter initialization and a new method for predicting effective learning …

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Multi-Stage Construction Of The Little Cottonwood Stock, Utah: Origin, Intrusion, Venting,Mineralization, And Mass Movement, Collin G. Jensen Jul 2019

Multi-Stage Construction Of The Little Cottonwood Stock, Utah: Origin, Intrusion, Venting,Mineralization, And Mass Movement, Collin G. Jensen

Theses and Dissertations

The Little Cottonwood stock in central Utah, USA, is a composite granitic pluton that hosts the White Pine porphyry Mo-W deposit towards its northeast margin. The deposit is centered on the smaller White Pine intrusion, and associated igneous units include the Red Pine porphyry, phreatomagmatic pebble dikes, and rhyolite dikes. Twelve new U-Pb zircon LA-ICP-MS ages, for samples from this deposit and in pebble dikes from the nearby East Traverse Mountains, give peak ages of about 30 Ma and 27 Ma for the Little Cottonwood stock and White Pine intrusion, respectively, which correlate well with ages from previous studies. Ages …

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Understanding The Wind-Dominated Landforms Of Saturn’S Moon Titan Through Earth Analogues, Jani Radebaugh, Eric Christiansen, Shannon Tass Jun 2019

Understanding The Wind-Dominated Landforms Of Saturn’S Moon Titan Through Earth Analogues, Jani Radebaugh, Eric Christiansen, Shannon Tass

Journal of Undergraduate Research

The largest moon of Saturn, Titan, has a thick atmosphere of nitrogen and a pressure similar to that of Earth at the surface. There are winds, strong enough to have produced two wind-dominated landforms similar to those on Earth – vast fields of sand dunes and smaller collections of wind-carved ridges, or yardangs. We seek to understand the relationships between the observed landforms and the winds and surface materials required to form them, both on Earth and Titan. This study of the shapes of winddominated landforms, dunes and yardangs, will help answer key questions about the surface of Titan at …

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Mentoring Astronomy Students Through Extensive Research (Master), Dr. Michael Joner Jun 2019

Mentoring Astronomy Students Through Extensive Research (Master), Dr. Michael Joner

Journal of Undergraduate Research

This Mentoring Environment Grant (MEG) proposed using the Brigham Young University West Mountain Observatory as a mentoring environment where students would experience what it is like to do research at a fully operational observatory by doing a wide variety of observations at regularly scheduled times over the course of several months during the spring and summer terms. The primary project in 2017 involved making nightly monitoring observations of the active Seyfert 1 galaxy Mrk 509 in support of a worldwide campaign involving more than a dozen ground–based and space–based observatories. In 2018, the primary monitoring campaign for extragalactic objects was …

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Applying Acoustic Beamforming In Sub-Arrays To Jet Engine Noise, David Van Komen, Kent Gee, Tracianne Nielson Jun 2019

Applying Acoustic Beamforming In Sub-Arrays To Jet Engine Noise, David Van Komen, Kent Gee, Tracianne Nielson

Journal of Undergraduate Research

In Jet engine noise is a large and complex area of research due to the intricacies of the variety of different mechanisms that produce noise traveling in different directions. The dominate noise source is called turbulent mixing noise (TMN) which is created by the interaction of the column of air mixing with the ambient air. Two types of TMN exist: large-scale TMN, the dominant noise source that travels away from the aircraft in the aft quadrant and fine-scale TMN that travels in all directions1. The second type of noise is known as broadband shock-associated noise (BBSAN), which is generated by …

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Identifying Unknown Satellites, Nicholas Van Alfen, Joseph Moody Jun 2019

Identifying Unknown Satellites, Nicholas Van Alfen, Joseph Moody

Journal of Undergraduate Research

Satellites are used for a wide range of purposes and by a wide range of organizations from private companies to governments. Specifically, what was of interest to us and the Air Force Research Laboratory (AFRL) with whom we collaborated was the need to identify different satellites using telescopes and determine their purpose. Finding a cheap way to determine the design of a satellite and its use would be of great interest to national security in determining whether a previously unknown satellite is potentially harmful to our own country’s satellites in orbit around the Earth.

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Computational Number Theory: Modular Forms, Paul Jenkins Jun 2019

Computational Number Theory: Modular Forms, Paul Jenkins

Journal of Undergraduate Research

In 2017 and 2018, the following students participated in the BYU Computational Number Theory research group under my direction and produced the following deliverables.

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Magnetron Sputtering For The Production Of Stable P-Type Zno Thin Films, Colter Stewart, Dr. John Colton Jun 2019

Magnetron Sputtering For The Production Of Stable P-Type Zno Thin Films, Colter Stewart, Dr. John Colton

Journal of Undergraduate Research

The principal purpose of my research is to produce stable, long-lasting, reproducible p-type zinc oxide for experimental and commercial use. Semiconductor devices made with zinc oxide (ZnO) have the potential to be a cheaper alternative to those made with gallium nitride (GaN). In addition, ZnO devices could also have superior physical and optical properties [1]. Because of ZnO’s wide band gap and high radiation tolerance, it could potentially be used for UV lasers and LEDs, and thin-film transistors (TFTs) [2]. However, because of natural defects in the ZnO lattice, p-type ZnO has historically been difficult to produce [3]. Our group’s …

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The Development Of Individualized Anemia Treatments Using Point Of Care Diagnostics To Distinguish Anemia Caused By Infection Or Chronic Inflammation, Dr. Richard Watt Jun 2019

The Development Of Individualized Anemia Treatments Using Point Of Care Diagnostics To Distinguish Anemia Caused By Infection Or Chronic Inflammation, Dr. Richard Watt

Journal of Undergraduate Research

Background: Anemia that accompanies inflammation is associated with negative outcomes for patients. Early intervention to treat anemia is an important step in improving the quality of life for anemic patients. Our lab proposed to develop simple diagnostic tests using a Lateral Flow Immunoassays (LFIs) to measure the presence of a hormone called hepcidin because hepcidin is the master regulator of iron homeostasis in the body and elevated hepcidin levels lead to anemia.

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Rational Design Of Multifunctional Enzyme-Like Catalysts For Assembly-Line Chemical Synthesis, David Michaelis Jun 2019

Rational Design Of Multifunctional Enzyme-Like Catalysts For Assembly-Line Chemical Synthesis, David Michaelis

Journal of Undergraduate Research

The main objectives of this proposal was to publish our preliminary findings in peptide catalysis and then submit applications for external funding. Both of these objectives were accomplished during the grant period. In the Fall of 2017, we published our first paper on the development of our new enzyme-like catalysts (ACS Catal. 2017, 7, 7704–7708). This publication should serve as a springboard for additional publications in the area (on which we are currently working) and help ensure external funding for this project. During 2017-2018, we submitted 3 grant applications to the NIH to help support this project. These submissions have …

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Inclusion Of Women In Computer Science, Naomi Johnson, Dr. Kevin Seppi Jun 2019

Inclusion Of Women In Computer Science, Naomi Johnson, Dr. Kevin Seppi

Journal of Undergraduate Research

Since the 1980’s, the percentage of computer science degrees awarded to women in the United States has fallen dramatically. There are growing numbers of men earning bachelor’s degrees in CS, and the numbers of women are increasing very slowly. For decades, researchers have been studying recruitment and retention of women and other minorities in CS, yet it is still not apparent what departments, professors, or students can do in order to get the numbers of women earning degrees in CS up again.

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Microbes And Metals: Purifying The Water Of Lake Titicaca, Sara Ludlow, Dr. Gregory T. Carling Jun 2019

Microbes And Metals: Purifying The Water Of Lake Titicaca, Sara Ludlow, Dr. Gregory T. Carling

Journal of Undergraduate Research

Pollution of Lake Titicaca has become a major threat to the health and lifestyle of the Uru people who use the lake water for their daily needs. Cities along the coast dump untreated sewage directly into the lake introducing dangerous microbial levels of Escherichia coli. Runoff from nearby mines increases the risk of toxic levels of lead, arsenic, and other heavy metals. Previous members of the ongoing Global Engineering Outreach (GEO) program identified biosand filtration as a viable option for mitigating these risks. As such, they implemented single stage biosand filters in the community, but they were never able to …

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Random Polynomial Interpolation From Known Roots In The Multivariate Case, Catherine Sawyer, Tyler Jarvis Jun 2019

Random Polynomial Interpolation From Known Roots In The Multivariate Case, Catherine Sawyer, Tyler Jarvis

Journal of Undergraduate Research

The purpose of this project was to develop a method by which sets of multivariate polynomials with known roots could be rapidly generated. Generating such polynomials would be of great use in testing root finding algorithms, yet remains an open problem

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Cancerous Male And Female Gene Expression, Clarissa Farmer, E. Shannon Tass Jun 2019

Cancerous Male And Female Gene Expression, Clarissa Farmer, E. Shannon Tass

Journal of Undergraduate Research

Genetic diagnosing is becoming more popular, as well as more and more accurate. However, many genetic diseases have complex genetic effects and are still not fully understood. Transthyretin Amyloidosis (ATTR; also known as familial or hereditary amyloidosis) is a terminal genetic disease. It is caused by unstable transthyretin proteins that fold improperly, and then deteriorate. The fragmented proteins are deposited outside of the cell and build up in the tissues over time, forming insoluble oligomers. The oligomers continue to grow into Amyloid fibrils, which adversely affect many organs in the body, eventually causing their failure. In order to accurately diagnose, …

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Cluster Analysis Via Random Partition Distributions, Brandon Carter, Dr. David B. Dahl Jun 2019

Cluster Analysis Via Random Partition Distributions, Brandon Carter, Dr. David B. Dahl

Journal of Undergraduate Research

Cluster analysis is an important exploratory data analysis technique used in a wide variety of fields. Cluster analysis seeks to discover a natural grouping of the data, where items in the same cluster or group are more similar than items from different clusters. Through our research, we developed a novel method for cluster analysis which takes pairwise distance information as input. Our new method improves upon traditional cluster analysis methods which also take pairwise distance information as input, such as hierarchical clustering. Our method, cluster analysis via random partition distributions (CaviarPD) is based on probability distributions and therefore allows the …

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Modeling Main Group Metal Alkane Functionalization Reactions In Highly Acidic Carboxylic And Sulfuric Acid Solvents, Lily H. Carlson, Daniel H. Ess Jun 2019

Modeling Main Group Metal Alkane Functionalization Reactions In Highly Acidic Carboxylic And Sulfuric Acid Solvents, Lily H. Carlson, Daniel H. Ess

Journal of Undergraduate Research

Our group is interested in identifying the unknown mechanisms of main-group C-H functionalization reactions. In the long term, our goal is to use computational chemistry tools to develop general principles on mechanisms, intermediates, reactivity, and selectivity for hydrocarbon C-H functionalization reactions by p-block main-group compounds as well as provide prediction of new catalysts and reactions. However, in providing these predictions, it remains unclear if different mechanistic pathways and intermediates will be predicted if examined in a complete solvent sphere (see Figure 1 for technical details). This is especially important for non-aqueous solvents such as carboxylic acids and sulfuric acid. To …

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Detecting Microcracks In Structures By Electromagnetic Excitation Of Acoustic Resonances, Joshua Gregg, Brian Anderson Jun 2019

Detecting Microcracks In Structures By Electromagnetic Excitation Of Acoustic Resonances, Joshua Gregg, Brian Anderson

Journal of Undergraduate Research

Stainless steel structures are often affected by stress corrosion cracking, which makes microscopic cracks that can go unnoticed and eventually cause the structure to fail. A useful method for detecting stress corrosion cracking is nonlinear resonant ultrasound spectroscopy (NRUS). NRUS involves vibrating a sample and looking for amplitude-dependent shifts in the sample’s resonance frequencies. NRUS tests are typically performed by driving vibrations in rods with piezoelectric transducers and measuring the amplitude-dependent shifts in the resonance frequencies. I am developing a different technique for driving the vibrations, which has never been used for NRUS. The technique uses a coil attached to …

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Heterodinuclear Co-Zr Compound Shows Increased Reactivity In Kumada Coupling, James Coombs, Daniel Ess Jun 2019

Heterodinuclear Co-Zr Compound Shows Increased Reactivity In Kumada Coupling, James Coombs, Daniel Ess

Journal of Undergraduate Research

Heterodinuclear compounds containing a metal–metal bond represent a potentially useful subclass of catalyst in organic synthesis. Heterodinuclear compounds offer the possibility of increased reactivity due to interactions between metal centers (Scheme 1A). These so-called cooperative effects can enhance reactivity by changing the electronic density, increasing nucleophilicity/electrophilicity of the reactive metal, and by lowering the energy barriers for changes in oxidation state. These changes in reactivity can allow a heterodinuclear compound to be an effective catalyst for many chemical reactions that would be unfeasible with a mononuclear analogue.

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Making Mri Scans Quieter Through Time-Reversal Acoustics And Active Noise Control, Trent Furlong, Brian Anderson Jun 2019

Making Mri Scans Quieter Through Time-Reversal Acoustics And Active Noise Control, Trent Furlong, Brian Anderson

Journal of Undergraduate Research

Noise from magnetic resonance imaging (MRI) equipment puts patients at risk for hearing damage.i Active noise control (ANC) systems have been implemented inside the MRI’s bore to reduce perceived noise, but the equipment used cannot have magnetic material or the ANC system will interfere with the MRI machine’s imaging quality. These systems are also limited in size because of the MRI machine’s small bore. Our project was to determine the feasibility of using time-reversal (TR) acoustics to remotely focus a noise-canceling signal to a desired point in space (e.g. a patient’s ear inside an MRI machine) and see if significant …

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Cyclic Peptide Catalyst Design, Millicent Campbell, David Michaelis Jun 2019

Cyclic Peptide Catalyst Design, Millicent Campbell, David Michaelis

Journal of Undergraduate Research

Enzymes found in nature are more efficient catalysts than those used in organic chemistry labs. However, natural enzymes are not ideal for organic synthesis because they only make one product and only work in specific conditions. The Michaelis lab designed a catalyst capable of mimicking enzyme-like reactivity in the lab. This catalyst consists of an alpha helix with an imidazolidinone catalyst and a thiourea catalyst (see figure 1). The imidazolidinone catalyst and thiourea catalysts are attached adjacent to each other on the alpha helix, which acts as a rigid scaffold that can mimic the proximity effects seen in natural enzymes. …

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Finding Planets Around Massive Stars, Elisabeth Frischnecht, Denise Stephens Jun 2019

Finding Planets Around Massive Stars, Elisabeth Frischnecht, Denise Stephens

Journal of Undergraduate Research

During the formation stages of a solar system, huge clouds of gas and dust contract into a disk around the growing star. These disks are the birthplace of planets, and are essential to our understanding of solar system formation. Historically, the search for planets outside of our solar system has typically been constrained to stars that are similar to the sun. However, Herbig Ae/Be (HAe/Be) stars offer promising results. HAe/Be stars are 2-10 times larger than the sun and retain their formation disks. These disks around these stars are brighter and larger than those around solar type stars, so they …

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Primordial Origins Of Supermassive Black Holes, William Black, David Neilson Jun 2019

Primordial Origins Of Supermassive Black Holes, William Black, David Neilson

Journal of Undergraduate Research

At the center of the Milky Way sits a supermassive black hole named Sagittarius A*1, which is over a million times the mass of our sun. Other galaxy centers host similar black holes which are up to thousands of times larger than even Sagittarius A*. Some of these giants have been sighted in the very early universe (700 million years after the Big Bang is still relatively early in the universe—it’s now been nearly 14 billion years!).

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Increasing Cryptographic Security Through Quantum Erasure, Richard Barney, Jean-Françios S. Van Huele Jun 2019

Increasing Cryptographic Security Through Quantum Erasure, Richard Barney, Jean-Françios S. Van Huele

Journal of Undergraduate Research

In our increasingly data-driven society, the ability to transmit secure messages is more essential than ever. This ability allows economies to thrive and protects both personal and national security. In order to achieve this security, cryptographers have developed methods to encrypt data. One of the most successful of these methods is to use a secure key to encrypt and decrypt the sensitive data. This method has been very successful but it is still possible for outside agents to obtain the secure key and thereby access sensitive information.

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Computational Design And Analysis Of Molecular Ethylene Oligomerization Catalysts, Doo Hyun Kwon Jun 2019

Computational Design And Analysis Of Molecular Ethylene Oligomerization Catalysts, Doo Hyun Kwon

Theses and Dissertations

Linear alpha olefins (LAOs) are key petrochemical precursors for the synthesis of larger polymers, detergents, plasticizers, and lubricants. Most catalytic ethylene oligomerization processes generate a wide distribution of LAO carbon chain lengths. A major ongoing industrial challenge is to develop homogeneous catalysts that result in selective and tunable ethylene oligomerization to 1-hexene and 1-octene alkenes. Quantum mechanical calculations coupled with rapidly advancing technology have enabled the ability to calculate small molecule systems with high accuracy. Employing computational models to advance from empirical to quantitative prediction of product selectivities has become an active area of exploration. In this work, we demonstrate …

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Analytical Expressions For Acoustic Radiation Modes Of Simple Curved Structures, Caleb Burley Goates Jun 2019

Analytical Expressions For Acoustic Radiation Modes Of Simple Curved Structures, Caleb Burley Goates

Theses and Dissertations

The search for a convenient connection between vibration patterns on a structure and the sound radiated from that structure is ongoing in structural acoustics literature. Common techniques are wavenumber domain methods, or representation of the vibration in terms of some basis, such as structural modes or elementary radiators, and calculating the sound radiation in terms of the basis. Most choices for a basis in this situation exhibit strong coupling between the basis functions, but there is one choice which does not: Acoustic radiation modes are by definition the basis that orthogonalizes the radiation operator, meaning the radiation modes do not …

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Multi-Human Management Of A Hub-Based Colony: Efficiency And Robustness In The Cooperative Best M-Of-N Task, John Rolfes Grosh Jun 2019

Multi-Human Management Of A Hub-Based Colony: Efficiency And Robustness In The Cooperative Best M-Of-N Task, John Rolfes Grosh

Theses and Dissertations

Swarm robotics is an emerging field that is expected to provide robust solutions to spatially distributed problems. Human operators will often be required to guide a swarm in the fulfillment of a mission. Occasionally, large tasks may require multiple spatial swarms to cooperate in their completion. We hypothesize that when latency, bandwidth, operator dropout, and communication noise are significant factors, human organizations that promote individual initiative perform more effectively and resiliently than hierarchies in the cooperative best-m-of-n task. Simulations automating the behavior of hub-based swarm robotic agents and groups of human operators are used to evaluate this hypothesis. To make …

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Mirror Symmetry For Non-Abelian Landau-Ginzburg Models, Matthew Michael Williams Jun 2019

Mirror Symmetry For Non-Abelian Landau-Ginzburg Models, Matthew Michael Williams

Theses and Dissertations

We consider Landau-Ginzburg models stemming from non-abelian groups comprised of non-diagonal symmetries, and we describe a rule for the mirror LG model. In particular, we present the non-abelian dual group G*, which serves as the appropriate choice of group for the mirror LG model. We also describe an explicit mirror map between the A-model and the B-model state spaces for two examples. Further, we prove that this mirror map is an isomorphism between the untwisted broad sectors and the narrow diagonal sectors in general.

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Secondary Preservice Mathematics Teachers' Curricular Reasoning, Kimber Anne Mathis Jun 2019

Secondary Preservice Mathematics Teachers' Curricular Reasoning, Kimber Anne Mathis

Theses and Dissertations

Researchers have found that teachers' decisions affect students' opportunity to learn. Prior researchers have investigated teachers' decisions while planning, implementing, or reflecting on lessons, but few researchers have studied teachers' decisions and their reasoning throughout the teaching process. It is important to study teachers' reasoning for why they make the decisions they do throughout the teaching process. Furthermore, because inservice and preservice teachers differ in experience and available resources that they draw on while making decisions, it is helpful to consider the resources PSTs' draw on while reasoning. Curricular reasoning is a framework that describes teachers' thinking processes when making …

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Basinward Trends In Fluvial Architecture, Connectivity, And Reservoir Characterization Of The Trail Member, Ericson Sandstone, Mesaverde Group In Wyoming, Utah, And Colorado, Usa, Chelsea Anne Jolley Jun 2019

Basinward Trends In Fluvial Architecture, Connectivity, And Reservoir Characterization Of The Trail Member, Ericson Sandstone, Mesaverde Group In Wyoming, Utah, And Colorado, Usa, Chelsea Anne Jolley

Theses and Dissertations

The Late Cretaceous Trail Member of the Ericson Sandstone represents a regionally extensive fluvial system that transported sediments from the Sevier fold and thrust belt and Uinta Mountain uplift to the Western Interior Seaway. The Trail Member is a petroleum reservoir target that has unpredictable production rates due to the unknown behavior and connectivity of channel sandstones. The abundant outcrop, wellbore, and core data available allows for a comprehensive analysis of how the fluvial architecture, connectivity, and reservoir quality change along 65 km of depositional dip. Observations made at Flaming Gorge and Clay Basin (most landward field locations) suggest a …

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