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Full-Text Articles in Physical Sciences and Mathematics

Along Strike Variability Of Thrust-Fault Vergence, Scott Royal Greenhalgh Jun 2014

Along Strike Variability Of Thrust-Fault Vergence, Scott Royal Greenhalgh

Theses and Dissertations

The kinematic evolution and along-strike variation in contractional deformation in overthrust belts are poorly understood, especially in three dimensions. The Sevier-age Cordilleran overthrust belt of southwestern Wyoming, with its abundance of subsurface data, provides an ideal laboratory to study how this deformation varies along the strike of the belt. We have performed a detailed structural interpretation of dual vergent thrusts based on a 3D seismic survey along the Wyoming salient of the Cordilleran overthrust belt (Big Piney-LaBarge field). The complex evolution of the thrust faults that parallel the overthrust belt is demonstrated by the switching of the direction of thrust …

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A New Geophysical Strategy For Measuring The Thickness Of The Critical Zone, Johnathan R. Yaede Jun 2014

A New Geophysical Strategy For Measuring The Thickness Of The Critical Zone, Johnathan R. Yaede

Theses and Dissertations

Estimates of the depth and variation of lateritic weathering profiles are especially important in tropical areas such as Oahu, HI. Shear-wave velocity data were obtained by a new application of Multi-channel Analysis of Surface Waves (MASW) to map the base of the critical zone, to show variations in the LWP, and to derive weathering rates. The MASW technique proved highly capable of imaging the base of the critical zone, confirmed by lithological well data and direct field measurements. Profile thickness can be obtained without drilling, which has applications in engineering and geochemical studies. The measured rate of advance of the …

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Facies Analysis, Sequence Stratigraphy And Paleogeography Of The Middle Jurassic (Callovian) Entrada Sandstone: Traps, Tectonics, And Analog, George R. Jennings Iii Jun 2014

Facies Analysis, Sequence Stratigraphy And Paleogeography Of The Middle Jurassic (Callovian) Entrada Sandstone: Traps, Tectonics, And Analog, George R. Jennings Iii

Theses and Dissertations

The late Middle Jurassic (Callovian) Entrada Sandstone has been divided into two general facies associations consisting primarily of eolian sandstones in eastern Utah and "muddy" redbeds in central Utah. Sedimentary structures within the redbed portion are explained by the interfingering of inland sabkha, alluvial, and eolian depositional systems. A complete succession from the most basinward facies to the most terrestrial facies in the Entrada Sandstone consists of inland sabkha facies overlain by either alluvial or eolian facies. Where both alluvial and eolian facies interfinger, alluvial facies overlain by eolian facies is considered a normal succession. Sequence boundaries, often identified by …

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Application Sharing From Mobile Devices With A Collaborative Shared Display, Richard S. Shurtz Jun 2014

Application Sharing From Mobile Devices With A Collaborative Shared Display, Richard S. Shurtz

Theses and Dissertations

With the increasing ubiquity of smartphones, tablets, and large pixel-rich displays, there are many exciting new possibilities for using these devices for collaborative work. While there already exist hardware and software that support communication and interaction between mobile devices and shared displays, application sharing in these scenarios is still limited and inflexible. We present a new method of application sharing which allows collaborators to download clips or snapshots of each other's applications. These snapshots can be used to re-launch and resume the shared application back to the state it was in when it was shared. We have built a system …

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Musical Motif Discovery In Non-Musical Media, Daniel S. Johnson Jun 2014

Musical Motif Discovery In Non-Musical Media, Daniel S. Johnson

Theses and Dissertations

Many music composition algorithms attempt to compose music in a particular style. The resulting music is often impressive and indistinguishable from the style of the training data, but it tends to lack significant innovation. In an effort to increase innovation in the selection of pitches and rhythms, we present a system that discovers musical motifs by coupling machine learning techniques with an inspirational component. The inspirational component allows for the discovery of musical motifs that are unlikely to be produced by a generative model, while the machine learning component harnesses innovation. Candidate motifs are extracted from non-musical media such as …

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Discovery Of Novel Serum Biomarkers For Diagnosing And Staging Alzheimer's Disease, Dipti Jigar Shah Jun 2014

Discovery Of Novel Serum Biomarkers For Diagnosing And Staging Alzheimer's Disease, Dipti Jigar Shah

Theses and Dissertations

Discovery of Novel Serum Biomarkers for Diagnosing and Staging Alzheimer’s DiseaseDipti Jigar ShahDepartment of Chemistry and Biochemistry, BYUDoctor of PhilosophyAlzheimer’s disease (AD) is an untreatable neurologic disease affecting more than 5 million Americans, most over 60 years of age. Protein plaques and neurofibrillary tangles typify AD brain pathology and are thought to cause the progressive dementia and brain shrinkage observed in AD. Currently there are no methods to diagnose the disease at a time before damage becomes irreversible.Biochemical tests for AD using cerebrospinal fluid analysis or neuroimaging are not yet sufficiently sensitive and specific, and they are invasive. This points …

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Application Of An Isogeometric Boundary Element Method To The Calculation Of Acoustic Radiation Modes And Their Efficiencies, Candice Marie Humpherys Jun 2014

Application Of An Isogeometric Boundary Element Method To The Calculation Of Acoustic Radiation Modes And Their Efficiencies, Candice Marie Humpherys

Theses and Dissertations

In contrast to the structural modes, which describe the physical motion of vibrating structures, acoustic radiation modes describe the radiated sound power. Radiation modes are beneficial in active noise control because reducing an efficiently radiating radiation mode guarantees the reduction of radiated sound power. Much work has been done to calculate the radiation modes for simple geometries, where analytic solutions are available. In this work, isogeometric analysis (IGA) is used to provide a tool capable of analyzing the radiation modes of arbitrarily complex geometries. IGA offers increased accuracy and efficiency by using basis functions generated from Non-Uniform Rational B-Splines (NURBS) …

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The Bell Springs Formation: Characterization And Correlationof Upper Triassic Strata In Northeast Utah, Skyler Bart May Jun 2014

The Bell Springs Formation: Characterization And Correlationof Upper Triassic Strata In Northeast Utah, Skyler Bart May

Theses and Dissertations

Upper Triassic strata that lie between the Chinle Formation and Nugget Sandstone along the south flank of the Uinta Mountains in northeastern Utah are distinctive. In the past, these rocks have been lumped together with the overlying or underlying units. These strata are equivalent to the Bell Springs Member of the Nugget Sandstone as defined in Wyoming and perhaps to the Rock Point Formation of the Chinle Formation near the Four Corners region. In this study, these rocks will be called the Bell Springs Formation following the usage of Lucas (1993) in Wyoming. The unit is regionally mappable in northeastern …

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A New Public-Key Cryptosystem, Christopher James Hettinger Jun 2014

A New Public-Key Cryptosystem, Christopher James Hettinger

Theses and Dissertations

Public key cryptosystems offer important advantages over symmetric methods, but the most important such systems rely on the difficulty of integer factorization (or the related discrete logarithm problem). Advances in quantum computing threaten to render such systems useless. In addition, public-key systems tend to be slower than symmetric systems because of their use of number-theoretic algorithms. I propose a new public key system which may be secure against both classical and quantum attacks, while remaining simple and very fast. The system's action is best described in terms of linear algebra, while its security is more naturally explained in the context …

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Convolutions And Convex Combinations Of Harmonic Mappings Of The Disk, Zachary M. Boyd Jun 2014

Convolutions And Convex Combinations Of Harmonic Mappings Of The Disk, Zachary M. Boyd

Theses and Dissertations

Let f_1, f_2 be univalent harmonic mappings of some planar domain D into the complex plane C. This thesis contains results concerning conditions under which the convolution f_1 ∗ f_2 or the convex combination tf_1 + (1 − t)f_2 is univalent. This is a long-standing problem, and I provide several partial solutions. I also include applications to minimal surfaces.

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Algebraic And Combinatorial Properties Of Schur Rings Over Cyclic Groups, Andrew F. Misseldine May 2014

Algebraic And Combinatorial Properties Of Schur Rings Over Cyclic Groups, Andrew F. Misseldine

Theses and Dissertations

In this dissertation, we explore the nature of Schur rings over finite cyclic groups, both algebraically and combinatorially. We provide a survey of many fundamental properties and constructions of Schur rings over arbitrary finite groups. After specializing to the case of cyclic groups, we provide an extensive treatment of the idempotents of Schur rings and a description for the complete set of primitive idempotents. We also use Galois theory to provide a classification theorem of Schur rings over cyclic groups similar to a theorem of Leung and Man and use this classification to provide a formula for the number of …

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Characterization Of Cretaceous Chalk Microporosity Related To Depositional Texture: Based Upon Study Of The Upper Cretaceous Niobrara Formation, Denver-Julesburg Basin, Colorado And Wyoming, P D. Pahnke May 2014

Characterization Of Cretaceous Chalk Microporosity Related To Depositional Texture: Based Upon Study Of The Upper Cretaceous Niobrara Formation, Denver-Julesburg Basin, Colorado And Wyoming, P D. Pahnke

Theses and Dissertations

Prompted by increased interest in understanding microporosity, recent efforts at describing and classifying pore types in mudstones have focused primarily on siliceous, gas producing unconventional reservoirs with little attention being paid to carbonate, mixed oil-and-gas producers. The Niobrara Formation in the Denver-Julesburg Basin is a self-sourced resource play producing oil and natural gas from low permeability chalks. Key reservoir lithologies consist of chalk, chalky marl and marl. These lithologies contain flattened chalk fecal pellets which play a significant role in providing porosity. Integration of depositional fabric with pore-type distribution emphasizes the unique textural and depositional nature of chalk and provides …

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The First 40ar/39ar Ages And Tephrochronologic Framework For The Jurassic Entrada Sandstone In Central Utah, Toby S. Dossett May 2014

The First 40ar/39ar Ages And Tephrochronologic Framework For The Jurassic Entrada Sandstone In Central Utah, Toby S. Dossett

Theses and Dissertations

The first 40Ar/39Ar ages of the Middle Jurassic Entrada Sandstone were derived from tephra beds found in central Utah. Eight air fall ash beds in the Entrada Sandstone, with 40Ar/39Ar biotite ages ranging from 168.1 ± 0.2 to 160.8 ± 0.2 Ma, help to establish the age of Entrada deposition. They were also used to create the first chronostratigraphic divisions within the mudstone-dominated Entrada Sandstone. Statistical cluster analysis of chemical data from electron microprobe analyses of phenocrysts were used as a second line of evidence to test absolute age and stratigraphic correlations. The first direct correlations of two distinct air …

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Elucidation And Improvement Of Algorithms For Mass Spectrometry Isotope Trace Detection, Robert Anthony Smith May 2014

Elucidation And Improvement Of Algorithms For Mass Spectrometry Isotope Trace Detection, Robert Anthony Smith

Theses and Dissertations

Mass spectrometry facilitates cutting edge advancements in many fields. Although instrumentation has advanced dramatically in the last 100 years, data processing algorithms have not kept pace. Without sensitive and accurate signal segmentation algorithms, the utility of mass spectrometry is limited. In this dissertation, we provide an overview and analysis of mass spectrometry data processing. A tutorial to ease the learning curve for those outside the field is provided. We draw attention to the lack of critical evaluation in the field and describe the resulting effects, including a glut of algorithm contributions of questionable novel contribution. To facilitate increased critical evaluation, …

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Kir2.1 Effects On Craniofacial And Limb Development In Knockout Mice, Joy Williams, Dr. Emily Bates Apr 2014

Kir2.1 Effects On Craniofacial And Limb Development In Knockout Mice, Joy Williams, Dr. Emily Bates

Journal of Undergraduate Research

Birth defects arise because of both genetic and environmental factors. Children with genetic alteration of the inwardly-rectifying potassium ion channel Kir2.1 channel have heart arrhythmias, impaired cognitive function, and facial and limb abnormalities. Children that suffer from Fetal Alcohol Syndrome have cognitive and social development problems, heart defects, and facial abnormalities—including small eyes, small head, small upper jaw, and a small upper lip1. Kir2.1 is bound and blocked by alcohol2 and thus we predicted that it is the molecular target of Fetal Alcohol Syndrome. We designed experiments to determine how Kir2.1 is required during development and found that within 14 …

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Acetylation Of Sod1 As A Regulator Of The Tumor Stress Response, Matthew Whited, Dr. Joshua L. Andersen Apr 2014

Acetylation Of Sod1 As A Regulator Of The Tumor Stress Response, Matthew Whited, Dr. Joshua L. Andersen

Journal of Undergraduate Research

In cancer patients, a lack of cell apoptosis (programmed cell death) coupled with increased levels of cell proliferation leads to the formation of a tumor. Among the available treatment options, cytotoxic chemotherapy is the most common. The primary purpose of this treatment is to induce tumor cell apoptosis. In many cases, tumor cells develop chemoresistance, rendering chemotherapy ineffective as a method to activate apoptosis. Understanding the mechanisms that lead to chemoresistance is a critical step toward developing methods to increase the effectiveness of chemotherapy treatments.

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The Use Of Alpha-1-Antitrypsin (Aat) In The Downregulation Of Nuclear Factor Kappa-Light-Chain-Enhancer Of Activated B Cells (Nf-Κb) As A Treatment For Acquired Immunodeficiency Syndrome (Aids), Aaron Mcbride, Dr. Gregory F. Burton Apr 2014

The Use Of Alpha-1-Antitrypsin (Aat) In The Downregulation Of Nuclear Factor Kappa-Light-Chain-Enhancer Of Activated B Cells (Nf-Κb) As A Treatment For Acquired Immunodeficiency Syndrome (Aids), Aaron Mcbride, Dr. Gregory F. Burton

Journal of Undergraduate Research

Current Human Immunodeficiency Virus (HIV) treatment is greatly hindered due to viral reservoirs throughout the body prolonging and perpetuating infection.i Large stores of HIV exist in the follicular dendritic cell (FDC) microenvironment, located primarily in the lymph nodes and spleen. Free-floating virus has a half-life of less than two hours; however, FDC-trapped virus has a half-life of over eight weeks and can be rescued in its infectious state longer than nine months after the initial infection,ii showing the role of FDCs as an HIV reservoir.iii Studies in the Gregory Burton laboratory focus on the interactions between HIV, FDCs, and CD4+ …

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Structure Of The Phlp1-Gβ-Cct Complex Reveals A Molecular Mechanism For Gprotein Β Subunit Folding And Βγ Dimer Assembly, Devon Blake, Dr. Barry Willardson Apr 2014

Structure Of The Phlp1-Gβ-Cct Complex Reveals A Molecular Mechanism For Gprotein Β Subunit Folding And Βγ Dimer Assembly, Devon Blake, Dr. Barry Willardson

Journal of Undergraduate Research

Cells detect and respond to a myriad of extracellular signals via seven-transmembrane G protein-coupled receptors and their associated G protein signaling pathways. The pathway is initiated by the binding of a signaling molecule, such as a hormone or neurotransmitter, to its binding site on the extracellular side of the receptor. This interaction activates the G protein heterotrimer, composed of Gβ, Gβ, and Gβ subunits, which functions by propagating the signal throughout the cell. First, however, the G protein heterotrimer must be assembled from its nascent polypeptides. The initial step in this process is the formation of the Gβγ dimer. Gβγ …

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Splicing Of Chicken Cyclooxygenase-2, Matthew Lelegren Apr 2014

Splicing Of Chicken Cyclooxygenase-2, Matthew Lelegren

Journal of Undergraduate Research

As described in the proposal, my goal was to further understand the mechanisms of mRNA processing of the chicken gene called Cyclooxygenase (COX)-2. There are many mechanisms by which mRNA molecules are modified in order to produce proteins that fulfill the needs of a given cell. The mechanism I chose to study was called alternative splicing, a process through which sequences are removed from the mRNA thereby altering the structure and function of the protein to be translated from its sequence. In brief summary splicing mechanisms, the cells possess machinery that recognize certain sequences, called splice sites, as a guide …

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Estrogen Signaling In Migraine Pathogenesis, Sarah Bahr, Dr. Emily Bates Apr 2014

Estrogen Signaling In Migraine Pathogenesis, Sarah Bahr, Dr. Emily Bates

Journal of Undergraduate Research

Migraine is a disorder that can include aura, headache, nausea, and hypersensitivity to all sensory modalities. It affects over thirty million people in the US. Migraines affect men and women equally until puberty, but overall migraines affect 3x more women than men. They also increase in frequency and severity during periods of estrogen fluctuation and often subside after menopause. Moreover, hormone supplements and birth control can affect migraine patterns. These correlations of migraine episodes to the menstrual cycle and increased pain sensitivity in response to estrogen suggest that differences in estrogen signaling contribute to migraine. We hypothesized that estrogen receptor …

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Virtual Pedigree: Genealogy Without Borders, Ryan Cheatham, Dr. William A. Barrett Apr 2014

Virtual Pedigree: Genealogy Without Borders, Ryan Cheatham, Dr. William A. Barrett

Journal of Undergraduate Research

Genealogists across the world face a unique and challenging problem. They attempt to sort through obscure historical data in order to find information about their ancestors, then they have to keep track of all the data they have found in an organized way. In today’s information age, viewing all this data should be simple and intuitive and provide easy access to research opportunities.

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Calculating Groundwater Recharge: The Navajo Sandstone Of Southern Utah, Matthew Olson, Dr. Greg Carling Apr 2014

Calculating Groundwater Recharge: The Navajo Sandstone Of Southern Utah, Matthew Olson, Dr. Greg Carling

Journal of Undergraduate Research

Southern Utah is world renowned for its beautiful canyons and red rock features. The Navajo Sandstone, an Early Jurassic formation created by 2000 feet of petrified sand dunes, is one of the primary features of this unique landscape. Groundwater in the Navajo Sandstone is important for sustaining life in arid southern Utah communities and ensuring recreational usability for state and national parks. Springs that discharge from the Navajo Sandstone aquifer in Zion National Park are a primary source of water to the Virgin River, which provides water for a number of towns in arid southern Utah (Christensen et al., 2005). …

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An Improved Temperature Index Model For Alpine Glaciers Using Derived Degree-Day Factors From Climatic Inputs, Durban G. Keeler, Dr. Summer Rupper Apr 2014

An Improved Temperature Index Model For Alpine Glaciers Using Derived Degree-Day Factors From Climatic Inputs, Durban G. Keeler, Dr. Summer Rupper

Journal of Undergraduate Research

Glaciers represent one of the most climatically sensitive and dynamic systems under study, and therefore have diverse implications for nations around the world. For example, Switzerland generates 56% of its power from hydroelectric facilities, many of them fed by glacial meltwater (SFOE, 2012). Many nations in the Himalayas are at risk of catastrophic flooding as glacial melt rates increase (Rupper et al., 2012). Attempts to comprehend past glacial changes can help us better understand modern changes in climate. The study of glacial melt rates over time therefore has potential regional and global significance.

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Quasigroup Structures Arising From Partial Latin Squares, William Cocke, Dr. Rodney Forcade Apr 2014

Quasigroup Structures Arising From Partial Latin Squares, William Cocke, Dr. Rodney Forcade

Journal of Undergraduate Research

Latin squares represent one of the oldest elements of modern algebra, despite being over- shadowed by the structurally superior subclass of nite groups. Every nite group generates a Latin square, an n by n grid wherein n distinct element appear exactly once in each row and column. This grid is a Latin square

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Femtosecond Frequency Comb Lock, Daniel Thrasher, Dr. Scott Bergeson Apr 2014

Femtosecond Frequency Comb Lock, Daniel Thrasher, Dr. Scott Bergeson

Journal of Undergraduate Research

Laser frequency control is imperative for cold atom experimentation. In our lab we use finely tuned lasers to optically cool and trap calcium atoms. Our ability to successfully trap atoms is highly dependent on the stability of the lasers we use to cool them. After trapping the atoms we use more finely tuned lasers to reveal how cold the atoms are and how quickly they leave our trap. Previous to this work our lasers were limited to 20 MHz precision. By installing a femtosecond laser as a standard by which to stabilize the other lasers in our experiment we successfully …

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Development Of A Data Reduction Pipeline For The Rovor Observatory, Thayne Mccombs, Dr. Joseph Ward Moody Apr 2014

Development Of A Data Reduction Pipeline For The Rovor Observatory, Thayne Mccombs, Dr. Joseph Ward Moody

Journal of Undergraduate Research

The ROVOR observatory is a robotic, remotely controlled telescope in Delta, Utah. Since it is remotely controlled and semi-automated, it produces a very large amount of raw data. Unfortunately it took much longer to process and analyze the data than to acquire it, and, therefore, we had a backlog of over two years of data that was waiting to be processed. This delay in analyzing data was detrimental to monitoring projects because without the analysis of recent data it is difficult to determine the most interesting targets to observe.

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Superparamagnetic Behavior Of Magnetite Nanoparticles: Preparation And Characterization, Matea Trevino, Dr. Karine Chesnel Apr 2014

Superparamagnetic Behavior Of Magnetite Nanoparticles: Preparation And Characterization, Matea Trevino, Dr. Karine Chesnel

Journal of Undergraduate Research

Magnetite (Fe3O4) nanoparticles have the unique ability of being superparamagnetic. When no field is applied to the nanoparticles, the nanoparticles’ assembly has a net magnetization of zero, meaning that the nanoparticles’ magnetic moments align in random positions leading to a net magnetization of zero. When a field is applied, the particles’ magnetic moments align with the magnetic field. This is considered superparamagnetic because this is looked at on the nanometer (nm) scale and not the atomic scale. Being able to understand this phenomenon will open up many doors in technology and medical usage. Nanocrystals, such as Fe3O4 particles, are good …

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Dynamics Of Multi-Spin Systems : Landau-Lifshitz-Gilbert Model And Ferromagnetic Pattern Formation, Soyoung Jung, Dr. Manuel Berrondo Apr 2014

Dynamics Of Multi-Spin Systems : Landau-Lifshitz-Gilbert Model And Ferromagnetic Pattern Formation, Soyoung Jung, Dr. Manuel Berrondo

Journal of Undergraduate Research

Modeling has been an important part of many fields of research. Even though it sometimes could be considered to be non-practical, it has sharpened the questions and has been a useful tool for experimental research to understand what is being observed in the laboratory. Likewise, the Heisenberg model constitutes an essential stepping stone to understand anti/ferromagnetism in magnetic materials. We have been able to develop a spin model using Landau-Lifshitz-Gilbert equation enhanced with anisotropy and long range interaction that is comparable to experimental results.

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Phase-Correlation And Propagation Analysis Of Near-Field Military Jet Noise, Jazz Myres, Dr. Kent Gee Apr 2014

Phase-Correlation And Propagation Analysis Of Near-Field Military Jet Noise, Jazz Myres, Dr. Kent Gee

Journal of Undergraduate Research

According to the Office of Naval Research (ONR), the United States Department of Veteran Affairs spent over $1 billion dollars on military hearing loss compensation in 2010 alone1. A major cause of hearing loss is exposure to high Sound Pressure Levels, which are caused by military aircraft. These severe levels and high risks are what motivate the overarching goal of all jet noise research: to attenuate the sound impact and reduce the risk of hearing loss. My research project helps this overall purpose by characterizing jet noise and innovating more complete methods of jet noise study. The purpose of this …

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Generation Of A Low Velocity Controlled Beam Of Sr Ions, Jarom Jackson, Dr. Dallin Durfee Apr 2014

Generation Of A Low Velocity Controlled Beam Of Sr Ions, Jarom Jackson, Dr. Dallin Durfee

Journal of Undergraduate Research

The purpose of this project was to produce a slow controlled beam of Strontium (Sr) ions. This is a key step in a proposed experiment to build an ion interferometer capable of measuring electric fields to a degree of sensitivity that has never been done before. This device will be useful in conducting a number of new experiments and will help test and push the boundaries of modern electromagnetic theory.

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