Physical Sciences and Mathematics Commons^™

Measuring Frequency Noise For Use In Preventing Mode Hops In Extended Cavity Diode Lasers, Mckinley Pugh, Dallin Durfee

Journal of Undergraduate Research

Diode lasers are useful in physics because they are relatively cheap and robust, they are available in a number of wavelengths, and they are tunable. However, because diode lasers have large bandwidths compared to atomic resonances, a reflection grating is added outside the laser. This creates the extended cavity in extended cavity diode lasers (ECDLs) and forces the lasers to operate at a narrower line width, one acceptable for use in atomic physics. Unfortunately, because the ECDL has many factors trying to control the wavelength of the laser (e.g. temperature, current, grating angel and position) small changes in the lasers …

Streamlining The 3d Animation Process, Dylan Hoffman, Kelly Loosli

Journal of Undergraduate Research

I knew from the beginning that this project – centered around improving the collaborative process of making a 3D animated film across several “stages” and made by several artists of different specialties, temperaments, and backgrounds – would be two-fold. The first phase was learning more about the process itself, and how each phase related to another. The second, zoning in on an area that has been a weakness for BYU Animated Films in the past – character effects and cloth simulation. The project evolved much over the course of the year, with far more time and value being placed in …

Girl’S Cybersecurity Camp, Sarah Cunha, Dale Rowe

Journal of Undergraduate Research

In 2015, the BYU Cybersecurity Research Lab (CSRL) held its first annual summer camp for Girls aged 14-18. A total of 38 girls attended the week’s activities and workshops. While over 75% of girls indicated they had taken a computing-related class, only 40% reported any significant interest in cybersecurity prior to the summercamp with 10% believing they had some experience in the field. At the conclusion of the camp, 80% of attendees reported a significant interest in the field with 100% of attendees interested in attending a similar event again.

Reflectometry Of Aluminum Thin Films In The Vacuum Ultraviolet, Benjamin Smith, R. Steven Turley

Journal of Undergraduate Research

Vacuum Ultraviolet (VUV) is a range of light on the electromagnetic spectrum corresponding to wavelengths from 40 – 280 nm. VUV photons have too much energy to see visibly and are blocked completely by atmosphere. This wavelength range, however, shows promise for applications in space-based exoplanet research telescopes. Specifically, the chemical fingerprints that this light contains can tell us about the composition and formation of exoplanet atmospheres.

Systematic Analysis Of Nonlinearities In Complex Models, Alexander Shumway, Mark Transtrum

Journal of Undergraduate Research

Mathematical models are ubiquitous in science. Many models are nonlinear in the parameters and may have dozens to thousands of parameters and make hundreds to thousands of predictions. Analysis and application of these models is thus theoretically complicated and computationally expensive.

The standard method of model analysis is a model-by-model approach that relies on the intuition of expert researchers. Recent research, however, has shown that many models—known as sloppy models—are statistically similar, despite coming from widely varied fields⁴. This suggests the possibility of developing a theory of modeling in place of relying on expert intuition. Our research …

The Impact Of Snake Creek On The Provo River Watershed Chemistry, Tucker Chapman, Greg Carling

Journal of Undergraduate Research

Snake Creek is a tributary to the Provo River, which is an important water source for over two million people along the Wasatch Front. Arsenic concentrations in Snake Creek exceed the EPA limit of 10 μg/L and mixing water in the Provo River exceed the EPA (recommended level) of 1 μg/L. Snake creek contributes about 20% to the overall flow of the Provo River. This study focused on the probable source of arsenic in snake creek. Hot springs and faults are probable causes for high trace element contamination are were the focus of this study.

Dual Species Calcium And Ytterbium Magneto Optical Trap, Alexander Erickson, Scott Bergeson

Journal of Undergraduate Research

One area of particular interest in modern physics research is creating a viable fusion system for sustainable energy. Fusion occurs when a high energy plasma is manipulated in such a way that small atoms collide together, combining to create larger atoms and releasing tremendous amounts of harvestable energy. However, there are many theoretical, mathematical, and practical roadblocks to creating a stable fusion experiment. One practical limitation and one mathematical limitation are as follows: practically, much of the energy used to create a fusion-grade plasma ends up in the kinetic energy of the electrons and is lost to the experiment; mathematically, …

Measurement Of The Yb I 1S0-1P1 Transition Frequency At 399 Nm Using An Optical Frequency Comb, Michaela Kleinert, M. E. Gold Dahl, Scott D. Bergeson

Faculty Publications

We determine the frequency of the Yb I ¹S₀-¹P₁ transition at 399 nm using an optical frequency comb. Although this transition was measured previously using an optical transfer cavity [D. Das et al., Phys, Rev. A 72, 032506 (2005)], recent work has uncovered significant errors in that method. We compare our result of 751 526 533.49 ± 0.33 MHz for the ¹⁷⁴Yb isotope with those from the literature and discuss observed differences. We verify the correctness of our method by measuring the frequencies of well-known transitions in Rb and Cs, and by …

The Solenoid And Warsawanoid Are Sharkovskii Spaces, Tyler Willes Hills

Theses and Dissertations

We extend Sharkovskii's theorem concerning orbit lengths of endomorphisms of the real line to endomorphisms of a path component of the solenoid and certain subspaces of the Warsawanoid. In particular, Sharkovskii showed that if there exists an orbit of length 3 then there exist orbits of all lengths. The solenoid is the inverse limit of double covers over the circle, and the Warsawanoid is the inverse limit of double covers over the Warsaw circle. We show Sharkovskii's result is true for path components of the solenoid and certain subspaces of the Warsawanoid.

High Flow Air Sampler For Rapid Analysis Of Volatile And Semi-Volatile Organic Compounds, Xiaofeng Xie

Theses and Dissertations

Volatile and semi-volatile organic compounds are ubiquitous, and some of them are hazardous. The ability to rapidly detect and identify trace levels of them in air has become increasingly important. The conventional device used today for sampling and concentrating them in air is thermal desorption tubes filled with specific sorbents, which can only collect air samples at flow rates of 100-200 mL/min. In order to detect low concentration (ppt level) VOC compounds, long sampling time (>2 h) and sensitive detection are required. At the same time, portable instrumentation for on-site analysis has been developing rapidly. The somewhat lower performance …

Cooling Before Super-Eruption: No Role For Rejuvenation In The Cottonwood Wash Tuff Magma Body, Southern Great Basin Ignimbrite Province, Utah And Nevada, Keryn Tobler Ross

Theses and Dissertations

The model of rejuvenation of a near-solidus crystal mush to produce large volumes of crystal-rich magma is tested here by analyzing the mineralogical, chemical, modal, and physical characteristics of the 31.1 Ma super-eruptive (2000 km3) Cottonwood Wash Tuff. It is the oldest in a series of three so-called "monotonous intermediate" ignimbrites from the Indian Peak-Caliente volcanic field in southern Utah and Nevada. A crystal-rich (~50% Pl > Qz ≈ Hbl ≈ Bt > Mag ≈ Ilm > Cpx + Zrn + Ap+ Po) dacite (62 - 69 wt% SiO2), the Cottonwood Wash Tuff is similar in age, volume, mineralogy, crystallinity, and elemental composition …

Compression Bodies And Their Boundary Hyperbolic Structures, Vinh Xuan Dang

Theses and Dissertations

We study hyperbolic structures on the compression body C with genus 2 positive boundary and genus 1 negative boundary. We consider individual hyperbolic structures as well as special regions in the space of all such hyperbolic structures. We use some properties of the boundary hyperbolic structures on C to establish an interesting property of cusp shapes of tunnel number one manifolds. This extends a result of Nimershiem in [26] to the class of tunnel number one manifolds. We also establish convergence results on the geometry of compression bodies. This extends the work of Ito in [13] from the punctured-torus case …

Advanced Data Analysis Tools And Multi-Instrument Material Characterization, Bhupinder Singh

Theses and Dissertations

My dissertation focuses on (i) the development of new analysis tools and methodologies for analyzing X-ray photoelectron spectroscopy (XPS) and time-of-flight secondary ion mass spectrometry (ToF-SIMS) data, and (ii) the comprehensive characterization of materials (nanodiamonds) using a multi-instrument approach. Chapter 1 contains (i) a discussion of the two techniques I focused on most in my work: XPS and ToF-SIMS, (ii) a discussion of the common chemometrics techniques used to analyze data from these methods, and (iii) the advantages/rationale behind the multi-instrument characterization of materials. Chapter 2 describes various good practices for obtaining reasonable peak fits in XPS, which can also …

Silicon Carbon Nanotube Lithium Ion Batteries, Lawrence Kent Barrett

Theses and Dissertations

Silicon has the highest theoretical capacity of any known anode material, and silicon coated carbon nanotubes (Si-CNTs) have shown promise of dramatically increasing battery capacity. However, capacity fading with cycling and low rate capability prevent widespread use. Here, three studies on differing aspects of these batteries are presented. Here, three studies on differing aspects of these batteries are presented. The first examines the rate capability of these batteries. It compares the cycling of electrodes hundreds of microns thick with and without ten micron access holes to facilitate diffusion. The holes do not improve rate capability, but thinner coatings of silicon …

Construction Of A 408 Nm Laser System For Use In Ion Interferometry, Lawrence Archibald

Theses and Dissertations

This work reports on the construction of a 408 nm laser system designed to drive stimulated Raman transitions between the F = 4 and F = 5 2 S 1/2 states of 87 Sr + using the 2 P 3/2 state as the intermediate state. This laser system will be used as part of a 87 Sr + ion interferometer. This work also includes a discussion of relevant theory describing the interaction of the ions and laser, along with a calculation of the transition rates as a function of laser power and detuning.

Cooling Before Super-Eruption: No Role For Rejuvenation In The Cottonwood Wash Tuff Magma Body, Southern Great Basin Ignimbrite Province, Utah And Nevada, Keryn Tobler Ross

Theses and Dissertations

The model of rejuvenation of a near-solidus crystal mush to produce large volumes of crystal-rich magma is tested here by analyzing the mineralogical, chemical, modal, and physical characteristics of the 31.1 Ma super-eruptive (2000 km3) Cottonwood Wash Tuff. It is the oldest in a series of three so-called “monotonous intermediate” ignimbrites from the Indian Peak-Caliente volcanic field in southern Utah and Nevada. A crystal-rich (~50% Pl > Qz ≈ Hbl ≈ Bt > Mag ≈ Ilm > Cpx + Zrn + Ap+ Po) dacite (62 – 69 wt% SiO2), the Cottonwood Wash Tuff is similar in age, volume, mineralogy, crystallinity, and elemental composition …

Superimposed And Auxiliary Dunes Of The Northern Namib Sand Sea: A Ground-Penetrating Radar Study, Clayton K. Chandler

Theses and Dissertations

Understanding modern features allows for their use as analogues for understanding the environments of the past and even environments on other planetary bodies. This study uses Ground-Penetrating Radar (GPR) to image the near surface sedimentary structures on a large linear dune in the northern Namib Sand Sea and image the sedimentary structure of an auxiliary dune. GPR data was collected using a 200 MHz antenna with a continuous scan method and was processed by removing direct arrival, gain balancing, migration and more which produced the highest resolution imagery from this region to date. Large dune data was analyzed to determine …

Facilitating Corpus Annotation By Improving Annotation Aggregation, Paul L. Felt

Theses and Dissertations

Annotated text corpora facilitate the linguistic investigation of language as well as the automation of natural language processing (NLP) tasks. NLP tasks include problems such as spam email detection, grammatical analysis, and identifying mentions of people, places, and events in text. However, constructing high quality annotated corpora can be expensive. Cost can be reduced by employing low-cost internet workers in a practice known as crowdsourcing, but the resulting annotations are often inaccurate, decreasing the usefulness of a corpus. This inaccuracy is typically mitigated by collecting multiple redundant judgments and aggregating them (e.g., via majority vote) to produce high quality consensus …

Hand-Portable Capillary Liquid Chromatography Instrumentation, Sonika Sharma

Theses and Dissertations

This dissertation focuses on the development of hand-portable capillary liquid chromatography (LC) instrumentation. In this work, battery-operable nano-flow pumping systems (isocratic and gradient) were developed and integrated with portable UV-absorption detectors for capillary LC. The systems were reduced in size to acceptable weights and power usage for field operation. A major advantage of the pumps is that they do not employ a splitter, since they were specifically designed for capillary column use, thereby greatly reducing solvent consumption and waste generation. UV-absorption detectors were specifically designed and optimized for on-column detection to minimize extra-column band broadening. Initially, an isocratic nano-flow pumping …

Cvic: Cluster Validation Using Instance-Based Confidences, Dean M. Lebaron

Theses and Dissertations

As unlabeled data becomes increasingly available, the need for robust data mining techniques increases as well. Clustering is a common data mining tool which seeks to find related, independent patterns in data called clusters. The cluster validation problem addresses the question of how well a given clustering fits the data set. We present CVIC (cluster validation using instance-based confidences) which assigns confidence scores to each individual instance, as opposed to more traditional methods which focus on the clusters themselves. CVIC trains supervised learners to recreate the clustering, and instances are scored based on output from the learners which corresponds to …

Development And Validation Of A Physically Based Ela Model And Its Application To The Younger Dryas Event In The Graubünden Alps, Switzerland, Durban Gregg Keeler

Theses and Dissertations

The rapid rate of global warming currently underway highlights the need for a deeper understanding of abrupt climate change. The Younger Dryas is a Late-Glacial climate event of widespread and unusually rapid change whose study can help us address this need for increased understanding. Reconstructions from the glacial record offer important contributions to our understanding of the Younger Dryas due to (among other things) the direct physical response of glaciers to even minor perturbations in climate. Because the glacier equilibrium line altitude (ELA) provides a more explicit comparison of climate than properties such as glacier length or area, ELA methods …

Alternating Direction Implicit Method With Adaptive Grids For Modeling Chemotaxis In Dictyostelium Discoideum, Christopher F. Loomis

Theses and Dissertations

Dictyostelium discoideum (Dd) is a model organism, studied for reasons from cell movement to chemotaxis to human disease control. Creating a computer model of the life cycle of Dd has garnered great interest, one part of which is the Aggregation Stage, where thousands of amoeba gather together to form a slug. Chemotaxis is the mechanism through which this is accomplished. This thesis develops two- and three-dimensional alternating direction implicit code which solves the diffusion equation on an adaptive grid. The calculated values for both two and three dimensions are checked against the actual solution and error results are provided. Comparisons …

Data Selection Using Topic Adaptation For Statistical Machine Translation, Hitokazu Matsushita

Theses and Dissertations

Statistical machine translation (SMT) requires large quantities of bitexts (i.e., bilingual parallel corpora) as training data to yield good quality translations. While obtaining a large amount of training data is critical, the similarity between training and test data also has a significant impact on SMT performance. Many SMT studies define data similarity in terms of domain-overlap, and domains are defined to be synonymous with data sources. Consequently, the SMT community has focused on domain adaptation techniques that augment small (in-domain) datasets with large datasets from other sources (hence, out-of-domain, per the definition). However, many training datasets consist of topically diverse …

Building 3d-Printed Widgets To Incorporate Into Prototypes, David E. Brandt

Theses and Dissertations

Creating interactive prototypes can be a long and difficult process. It requires expertise in various fields. Prior work in developing interactive prototypes minimize time required to make a prototype, but generally sacrifice fidelity for fluidity. Advances in 3D printing create new opportunities to prototype with greater fidelity and fluidity. We investigate the use of several kinds of sensors, including IR photo interrupters, IR photo reflectors, push button switches, and potentiometers, to create interactive prototypes. We first design a library of 3D printable interaction components, buttons, sliders, and knobs using those sensors then we develop software to transform interaction events into …

Interactive Machine Assistance: A Case Study In Linking Corpora And Dictionaries, Kevin P. Black

Theses and Dissertations

Machine learning can provide assistance to humans in making decisions, including linguistic decisions such as determining the part of speech of a word. Supervised machine learning methods derive patterns indicative of possible labels (decisions) from annotated example data. For many problems, including most language analysis problems, acquiring annotated data requires human annotators who are trained to understand the problem and to disambiguate among multiple possible labels. Hence, the availability of experts can limit the scope and quantity of annotated data. Machine-learned pre-annotation assistance, which suggests probable labels for unannotated items, can enable expert annotators to work more quickly and thus …

Low-Shield Volcanism: A Comparison Of Volcanoes On Syria Planum, Mars And Snake River Plain, Idaho, Amanda Olivia Henderson

Theses and Dissertations

Volcanoes are key indicators of a planet's internal structure, mechanics, and evolutionary history. Consequently, understanding the types and ages of volcanoes on a planet's surface is an important endeavor. In an attempt to better understand the relationship between morphometry and volcanic processes, we compared low-shield volcanoes on Syria Planum, Mars, with basaltic shields of the eastern Snake River Plain. We used 133 volcanoes on Syria Planum that are covered by Mars Orbiting Laser Altimeter (MOLA) and High Resolution Stereo Camera (HRSC) elevation data and 246 eSRP shields covered by the National Elevation Dataset (NED) for this comparison. Shields on Syria …

Mechanisms And Timing Of Pluton Emplacement In Taranaki Basin, New Zealand Using Three-Dimensional Seismic Analysis, Phillip C. Cammans

Theses and Dissertations

Several off-shore volcano-plutonic complexes are imaged in detail in the Parihaka 3D seismic survey in the Taranaki Basin of New Zealand. Three intrusions were analyzed for this study. Part of the Mohakatino Volcanic Centre (15 to 1.6 Ma), these intrusions have steep sides, no resolvable base reflectors, no internal stratification or structure, and they exhibit doming and faulting in the sedimentary strata above the intrusions. Deformation along the sides is dominated by highly attenuated, dipping strata with dips of 45° or higher that decrease rapidly away from the intrusions. Doming extends several hundred meters from the margins and produced many …

Mass Spectrometry Based Proteomics And Lipidomics Studies, Huan Kang

Theses and Dissertations

Mass spectrometry has emerged as having a vital role in various applications to biochemical fields. In this thesis, we have utilized a variety of mass spectrometry techniques for both bacteriophage proteomics and colostrum and milk lipidomics studies. Our first study was the proteome characterization of Great Salt Lake bacteriophage NS01 with SDS-PAGE GEL to separate the viral proteins and high performance liquid chromatography (HPLC) coupled with an LTQ Orbitrap to identify the proteins after in-gel digestion. In this project, we have successfully identified 11 proteins with high confidence, p-values < 0.01, including coat protein gp88 with a coverage of 91% and tail protein gp86 with a coverage of 40.96%, which facilitated the classification of NS01 as a T7-like phage. Our second study was the discovery of colostrum and milk biomarkers that can be used to predict the likelihood of development of production-related metabolic diseases (PRMDs) in dairy cows through a lipidomics approach. In this study, an electrospray ionization, time-of-flight mass spectrometer was applied to lipid profiling, quantification and significant biomolecule selection. A Q-Star quadrupole, orthogonal time-of-flight mass spectrometer and an Agilent 6530 accurate-mass quadrupole/time-of flight mass spectrometer were both used for lipid biomarker fragmentation and identification. According to linear discriminative statistical modeling, three panels of biomarkers were defined. A combination of 2 milk lipid predictors, including DG18:0/18:0 and TG 18:0/18:0/18:1, provided PRMD predictions with 75.0% sensitivity at 90.0% specificity. A combination of 3 colostrum lipid predictors, including TG16:0/18:1/18:3, DG16:0/16:0 and C₄₀H₆₀NO, provided PRMD prediction with 90.0% sensitivity at …

Information Behaviors Of Nuclear Scientists At Korea Atomic Energy Research Institute, Youngchoon Chun, Jiho Yi, Jung-Ran Park, Sangki Choi

Journal of East Asian Libraries

The goal of the study was to analyze the information use behaviors of researchers in the science and technology domain. A survey and interviews were conducted targeting nuclear scientists at the Korea Atomic Energy Research Institute. Study results indicate that the nuclear scientists mainly use the Institute library/information center and Internet portal/search engines during information acquisition. Easy access to information, accuracy, currency and cost are the most critical factors in selecting and obtaining information. The most frequently used database for executing research is the Institute’s electronic library (NUCLIS21) followed by the Citation Index SCOPUS. The results of the study indicate …

Image-Charge Detection €“ Novel Instrumentation And Applications, Brandon Lee Barney

Theses and Dissertations

Image-charge detection is an analytical technique in which a highly-charged particle is detected by the magnitude of the image current that it generates in a detecting electrode. This current is represented as a voltage between the charged particle and the sensing electrode. It is a single particle detection method, ideal for the analysis of large, variable mass particles such as biological cells. Some of the physical properties of Bacillus subtilis spores were explored using different applications of image-charge detection. B. subtilis is a gram-negative spore-forming bacteria that has been shown to exhibit extremophile behavior. The particular extremophile behavior that was …