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Full-Text Articles in Physical Sciences and Mathematics

The Investigation Of Functionalized Carbon Nanotubes For The Carbon Dioxide Capture And Ethane Oxidative Dehyrogenation Catalysts, Zheng Zhou Mar 2020

The Investigation Of Functionalized Carbon Nanotubes For The Carbon Dioxide Capture And Ethane Oxidative Dehyrogenation Catalysts, Zheng Zhou

Theses and Dissertations

Carbon nanotubes (CNT) have gained interest for wide use as both support and catalyst due to the ease of uniquely tunable surface chemistry. Increasingly severe greenhouse effects have attracted attention to novel materials and technologies capable of capturing carbon dioxide (CO2). In this context, we develop a CNT based solid state amine for the CO2 capture. CNT are functionalized under various methods as a support for polymeric amines. Polyethyleneimine are physically adsorbed on CNT and are further characterized and studied for reversible CO2 capture. We obtain a high CO2 capture capacity (6.78 mmol∙g-1) for linear polyethyleneimine (LPEI) and 6.18 mmol∙g-1 …


Retiming Smoke Simulation Using Machine Learning, Samuel Charles Gérard Giraud Carrier Mar 2020

Retiming Smoke Simulation Using Machine Learning, Samuel Charles Gérard Giraud Carrier

Theses and Dissertations

Art-directability is a crucial aspect of creating aesthetically pleasing visual effects that help tell stories. A particularly common method of art direction is the retiming of a simulation. Unfortunately, the means of retiming an existing simulation sequence which preserves the desired shapes is an ill-defined problem. Naively interpolating values between frames leads to visual artifacts such as choppy frames or jittering intensities. Due to the difficulty in formulating a proper interpolation method we elect to use a machine learning approach to approximate this function. Our model is based on the ODE-net structure and reproduces a set of desired time samples …


Gamma-Ray Burst Afterglow Dynamics In Inhomogeneous Interstellar Media, Jacob Fields Mar 2020

Gamma-Ray Burst Afterglow Dynamics In Inhomogeneous Interstellar Media, Jacob Fields

Undergraduate Honors Theses

Gamma-ray bursts (GRBs) are the most luminous electromagnetic phenomena in the universe, but much remains unknown about them. Many models invoked to explain their highly variable light curves are based on complicated dynamics and interactions involving the GRB progenitor but assume simple circumstellar environments. Many long GRBs, however, show late time optical and x-ray flares that may be an indication of a much richer environment. Relativistic hydrodynamics simulations are used to study a family of initial data with a relativistic blast wave encountering a dense circumstellar shell of matter, similar to what an aging star expelling the outer layers of …


An Analysis Of Opiate Prescription For Chronic Degenerative Disease And Other Pain Syndromes, Catherine Sawyer Mar 2020

An Analysis Of Opiate Prescription For Chronic Degenerative Disease And Other Pain Syndromes, Catherine Sawyer

Undergraduate Honors Theses

Utilizing the National Ambulatory Medical Care Survey (NAMCS) database, this thesis explores patterns of opiate prescribing during time period from 1993 to 2016, which includes the time period when the opiate crisis was recognized in the United States and efforts begun to combat it. We analyze these patterns particularly as they relate to patients who were prescribed opiates and who were simultaneously suffering from various chronic conditions, and interactions between prescription of opiates and diagnosis of chronic conditions. We examine which demographic groups were most likely to receive opiates, and considered opiate prescription trends among patients with any pain diagnosis …


Using Logical Specifications For Multi-Objective Reinforcement Learning, Kolby Nottingham Mar 2020

Using Logical Specifications For Multi-Objective Reinforcement Learning, Kolby Nottingham

Undergraduate Honors Theses

In the multi-objective reinforcement learning (MORL) paradigm, the relative importance of environment objectives is often unknown prior to training, so agents must learn to specialize their behavior to optimize different combinations of environment objectives that are specified post-training. These are typically linear combinations, so the agent is effectively parameterized by a weight vector that describes how to balance competing environment objectives. However, we show that behaviors can be successfully specified and learned by much more expressive non-linear logical specifications. We test our agent in several environments with various objectives and show that it can generalize to many never-before-seen specifications.


Orientable Single-Distance Codes For Absolute Incremental Encoders, Kristian Brian Sims Mar 2020

Orientable Single-Distance Codes For Absolute Incremental Encoders, Kristian Brian Sims

Theses and Dissertations

Digital encoders are electro-mechanical sensors that measure linear or angular position using special binary patterns. The properties of these patterns influence the traits of the resulting encoders, such as their maximum speed, resolution, tolerance to error, or cost to manufacture. We describe a novel set of patterns that can be used in encoders that are simple and compact, but require some initial movement to register their position. Previous designs for such encoders, called absolute incremental encoders, tend to incorporate separate patterns for the functions of tracking incremental movement and determining the absolute position. The encoders in this work, however, use …


Machine Learning For Effective Parkinson's Disease Diagnosis, Brennon Brimhall Mar 2020

Machine Learning For Effective Parkinson's Disease Diagnosis, Brennon Brimhall

Undergraduate Honors Theses

Parkinson’s Disease is a degenerative neurological condition that affects approximately 10 million people globally. Because there is currently no cure, there is a strong motivation for research into improved and automated diagnostic procedures. Using Random Forests, a computer can effectively learn to diagnose Parkinson’s disease in a patient with high accuracy (94%), precision (95%), and recall (91%) across the data of over 2800 patients. Using similar techniques, I further determine that the most predictive medical tests relate to tremors observed in patients.


Congruences For Coefficients Of Modular Functions In Levels 3, 5, And 7 With Poles At 0, Ryan Austin Keck Mar 2020

Congruences For Coefficients Of Modular Functions In Levels 3, 5, And 7 With Poles At 0, Ryan Austin Keck

Theses and Dissertations

We give congruences modulo powers of p in {3, 5, 7} for the Fourier coefficients of certain modular functions in level p with poles only at 0, answering a question posed by Andersen and Jenkins and continuing work done by the Jenkins, the author, and Moss. The congruences involve a modulus that depends on the base p expansion of the modular form's order of vanishing at infinity.


Analysis Of Identification Method For Bacterial Species And Antibiotic Resistance Genes Using Optical Data From Dna Oligomers, Ryan L. Wood, Tanner Jensen, Cindi Wadsworth, Mark Clement, Prashant Nagpal, William G. Pitt Feb 2020

Analysis Of Identification Method For Bacterial Species And Antibiotic Resistance Genes Using Optical Data From Dna Oligomers, Ryan L. Wood, Tanner Jensen, Cindi Wadsworth, Mark Clement, Prashant Nagpal, William G. Pitt

Faculty Publications

Bacterial antibiotic resistance is becoming a significant health threat, and rapid identification of antibiotic-resistant bacteria is essential to save lives and reduce the spread of antibiotic resistance. This paper analyzes the ability of machine learning algorithms (MLAs) to process data from a novel spectroscopic diagnostic device to identify antibiotic-resistant genes and bacterial species by comparison to available bacterial DNA sequences. Simulation results show that the algorithms attain from 92% accuracy (for genes) up to 99% accuracy (for species). This novel approach identifies genes and species by optically reading the percentage of A, C, G, T bases in 1000s of short …


Historical Milestones In Astronomy: As Shown Through The Byu Special Collections Archives, Dan Broadbent Jan 2020

Historical Milestones In Astronomy: As Shown Through The Byu Special Collections Archives, Dan Broadbent

Faculty Publications

Science Research: The “Long Conversation”

  • Ideas in science can take a long time to develop.
  • How do they develop?
  • These books document a part of a conversation that began 447 years ago and spanned a 153 year period… documenting:
  • how the overall nature of the universe was worked out,
  • the establishment of the scientific method, and the boundaries of religious authority,
  • and culminated in Isaac Newton’s book that presented his three laws of motion that allow us to explore the universe to this day.


Data For The Review Of Gamified Fitness Tracker Apps, Aatish Neupane, Derek Hansen, Anud Sharma, Jerry Alan Fails Jan 2020

Data For The Review Of Gamified Fitness Tracker Apps, Aatish Neupane, Derek Hansen, Anud Sharma, Jerry Alan Fails

ScholarsArchive Data

This is a supplemental dataset to a paper that reviews 103 gamified fitness tracker apps and analyzes the presence and usage of various game elements. This dataset contains the list of those apps that were reviewed. It also contains the coding that represents the presence of difference game elements.


Automatic Detection And Prevention Of Fake Key Attacks In Signal, Tarun Kumar Yadav Dec 2019

Automatic Detection And Prevention Of Fake Key Attacks In Signal, Tarun Kumar Yadav

Theses and Dissertations

The Signal protocol provides end-to-end encryption for billions of users in popular instant messaging applications like WhatsApp, Facebook Messenger, and Google Allo. The protocol relies on an app-specific central server to distribute public keys and relay encrypted messages between the users. Signal prevents passive attacks. However, it is vulnerable to some active attacks due to its reliance on a trusted key server. A malicious key server can distribute fake keys to users to perform man-in-the-middle or impersonation attacks. Signal applications support an authentication ceremony to detect these active attacks. However, this places an undue burden on the users to manually …


Cell Velocity Is Asymptotically Independent Of Force: A Differential Equation Model With Random Switching., J. C. Dallon, Emily J. Evans, Christopher P. Grant, William V. Smith Dec 2019

Cell Velocity Is Asymptotically Independent Of Force: A Differential Equation Model With Random Switching., J. C. Dallon, Emily J. Evans, Christopher P. Grant, William V. Smith

Faculty Publications

Numerical simulations suggest that average velocity of a biological cell depends largely on attachment dynamics and less on the forces exerted by the cell. We determine the relationship between two models of cell motion, one based on finite spring constants modeling attachment properties (a randomly switched differential equation) and a limiting case (a centroid model-a generalized random walk) where spring constants are infinite. We prove the main result of this paper, the Expected Velocity Relationship theorem. This result shows that the expected value of the difference between cell locations in the differential equation model at the initial time and at …


Controller Design For Coordinated Encirclement Of Moving Targets, Puneet Jain Dec 2019

Controller Design For Coordinated Encirclement Of Moving Targets, Puneet Jain

Theses and Dissertations

This thesis presents controllers that use relative range and bearing measurements to steer unmanned aerial vehicles (UAVs) to circular trajectories around stationary, constantly moving and constantly accelerating targets. The range and bearing to the target, along with their derivaties are estimated. These, along with the estimated local heading of the UAVs, are used in the control law, and to estimate the velocity of the target. In this work, six controllers are presented. The controller for a stationary target is derived using Lyapunov's direct method, and feedback linearization is used for the constant velocity and accelerating targets. A new controller is …


Inclusion Of Kinetic Proteomics In Multi-Omics Methods To Analyze Calorie Restriction Effects On Aging, Richard Hajime Carson Dec 2019

Inclusion Of Kinetic Proteomics In Multi-Omics Methods To Analyze Calorie Restriction Effects On Aging, Richard Hajime Carson

Theses and Dissertations

One of the greatest risk factors for disease is advanced age. As the human lifespan has increased, so too have the burdens of caring for an increasingly older population suffering from rising rates of cardiovascular disease, kidney disease, diabetes, and dementia. The need for improving medical technology and developing new therapies for age-related diseases is manifest. Yet our understanding of the processes of aging and how to attenuate the effects of aging remains incomplete. Various studies have established calorie restriction as a robust method for extending lifespan in laboratory organisms; however the mechanism is a topic of much debate. Advancing …


Exploring The Relationship Between Vocabulary Scaling And Algorithmic Performance In Text Classification For Large Datasets, Wilson Murray Fearn Dec 2019

Exploring The Relationship Between Vocabulary Scaling And Algorithmic Performance In Text Classification For Large Datasets, Wilson Murray Fearn

Theses and Dissertations

Text analysis is a significant branch of natural language processing, and includes manydifferent sub-fields such as topic modeling, document classification, and sentiment analysis.Unsurprisingly, those who do text analysis are concerned with the runtime of their algorithmsSome of these algorithms have runtimes that depend jointly on the size of the corpus beinganalyzed, as well as the size of that corpus's vocabulary. Trivially, a user may reduce theamount of data they feed into their model to speed it up, but we assume that users will behesitant to do this as more data tends to lead to better model quality. On the other …


Coordinated Persistent Homology And An Application To Seismology, Nickolas Brenten Callor Dec 2019

Coordinated Persistent Homology And An Application To Seismology, Nickolas Brenten Callor

Theses and Dissertations

The theory of persistent homology (PH), introduced by Edelsbrunner, Letscher, and Zomorodian in [1], provides a framework for extracting topological information from experimental data. This framework was then expanded by Carlsson and Zomorodian in [2] to allow for multiple parameters of analysis with the theory of multidimensional persistent homology (MPH). This particular generalization is considerably more difficult to compute and to apply than its predecessor. We introduce an intermediate theory, coordinated persistent homology (CPH), that allows for multiple parameters while still preserving the clarity and coherence of PH. In addition to introducing the basic theory, we provide a polynomial time …


An Equivalence Of Shape And Deck Groups; Further Classification Of Sharkovskii Groups, Tyler Willes Hills Dec 2019

An Equivalence Of Shape And Deck Groups; Further Classification Of Sharkovskii Groups, Tyler Willes Hills

Theses and Dissertations

In part one we show that for a compact, metric, locally path-connected topological space X, the shape group of X - as defined in Foundations of Shape Theory by Mardesic and Segal - is isomorphic to the inverse limit of discrete homotopy groups introduced by Conrad Plaut and Valera Berestovskii. We begin by providing the reader preliminary definitions of the fundamental group of a topological space, inverse systems and inverse limits, the Shape Category, discrete homotopy groups, and culminate by providing an isomorphism of the shape and deck groups for peano continua. In part two we develop work and provide …


Depositional Analysis Of A Holocene Carbonate Strand Plain Using High Resolution Gpr, Sediment Analysis, And C-14 Dating, Kaleb Robert Markert Dec 2019

Depositional Analysis Of A Holocene Carbonate Strand Plain Using High Resolution Gpr, Sediment Analysis, And C-14 Dating, Kaleb Robert Markert

Theses and Dissertations

Understanding modern carbonate depositional systems gives valuable insights into the interpretation of ancient carbonate systems. Ancient carbonate strand plains have the potential to act as productive hydrocarbon reservoirs because of their relatively high porosity. Unfortunately, they are difficult to identify in the rock record because of the lack of work done on modern analogues. San Salvador Island in the Bahamas hosts a well-exposed and easily accessible Holocene strand plain, ideal as a modern analogue. Sandy Hook, located on the southeast part of the island, consists of approximately 35 ridge-swale features that show signs of four distinct zones of deposition. In …


Electrical Conductivity Of The Aluminum Oxide Diffusion Barrier Following Catalytic Carbon Nanotube Growth, Berg Daniel Dodson Dec 2019

Electrical Conductivity Of The Aluminum Oxide Diffusion Barrier Following Catalytic Carbon Nanotube Growth, Berg Daniel Dodson

Theses and Dissertations

Carbon nanotube templated microfabrication (CNT-M) is a method that allows high-aspect ratio structures to be made for microelectromechanical systems (MEMS) devices. One concern when making monolithic electrical devices using CNT-M is that the aluminum oxide diffusion barrier will create too large of a resistance in the device. However, in developing CNT based MEMS devices, it has been observed that an electrical DC current is capable of transport from a conductive substrate, across the aluminum oxide, and through to the CNT structure grown on top of it. This thesis attempts to determine the mechanisms responsible for current being able to cross …


Materials Prediction Using High-Throughput And Machine Learning Techniques, Chandramouli Nyshadham Dec 2019

Materials Prediction Using High-Throughput And Machine Learning Techniques, Chandramouli Nyshadham

Theses and Dissertations

Predicting new materials through virtually screening a large number of hypothetical materials using supercomputers has enabled materials discovery at an accelerated pace. However, the innumerable number of possible hypothetical materials necessitates the development of faster computational methods for speedier screening of materials reducing the time of discovery. In this thesis, I aim to understand and apply two computational methods for materials prediction. The first method deals with a computational high-throughput study of superalloys. Superalloys are materials which exhibit high-temperature strength. A combinatorial high-throughput search across 2224 ternary alloy systems revealed 102 potential superalloys of which 37 are brand new, all …


Almost Homeomorphisms And Inscrutability, Michael Steven Andersen Dec 2019

Almost Homeomorphisms And Inscrutability, Michael Steven Andersen

Theses and Dissertations

“Homeomorphic'' is the standard equivalence relation in topology. To a topologist, spaces which are homeomorphic to each other aren't merely similar to each other, they are the same space. We study a class of functions which are homeomorphic at “most'' of the points of their domains and codomains, but which may fail to satisfy some of the properties required to be a homeomorphism at a “small'' portion of the points of these spaces. Such functions we call “almost homeomorphisms.'' One of the nice properties of almost homeomorphisms is the preservation of almost open sets, i.e. sets which are “close'' to …


Aspects Of Engaging Problem Contexts From Students' Perspectives, Tamara Kay Stark Dec 2019

Aspects Of Engaging Problem Contexts From Students' Perspectives, Tamara Kay Stark

Theses and Dissertations

Aspects of Engaging Problem Contexts From Students' PerspectivesTamara Kay Gandolph StarkDepartment of Mathematics Education, BYUMaster of ArtsToo many students have negative feelings towards mathematics which is causing them to disengage in their classrooms. This has led to student under-achievement. This study attempts to better understand how teachers can help students to reengage with mathematics by using more engaging contexts to develop mathematical content. The study began with the characteristics realistic, worthwhile, enjoyable or motivating as a framework for posing engaging problem contexts, which were synthesized from the current research literature. As students discussed what made contexts engaging, my understanding of …


Light-Field Style Transfer, David Marvin Hart Nov 2019

Light-Field Style Transfer, David Marvin Hart

Theses and Dissertations

For many years, light fields have been a unique way of capturing a scene. By using a particular set of optics, a light field camera is able to, in a single moment, take images of the same scene from multiple perspectives. These perspectives can be used to calculate the scene geometry and allow for effects not possible with standard photographs, such as refocus and the creation of novel views.Neural style transfer is the process of training a neural network to render photographs in the style of a particular painting or piece of art. This is a simple process for a …


Average Speech Directivity, Samuel D. Bellows, Claire M. Pincock, Jennifer K. Whiting, Timothy W. Leishman Nov 2019

Average Speech Directivity, Samuel D. Bellows, Claire M. Pincock, Jennifer K. Whiting, Timothy W. Leishman

Directivity

Speech directivity describes the angular dependence of acoustic radiation from a talker’s mouth and nostrils and diffraction about his or her body and chair (if seated). It is an essential physical aspect of communication affecting sounds and signals in acoustical environments, audio, and telecommunication systems. Because high-resolution, spherically comprehensive measurements of live, phonetically balanced speech have been unavailable in the past, the authors have undertaken research to produce and share such data for simulations of acoustical environments, optimizations of microphone placements, speech studies, and other applications. The measurements included three male and three female talkers who repeated phonetically balanced passages …


Recommending Games To Adults With Autism Spectrum Disorder(Asd) For Skill Enhancement Using Minecraft, Alisha Banskota Nov 2019

Recommending Games To Adults With Autism Spectrum Disorder(Asd) For Skill Enhancement Using Minecraft, Alisha Banskota

Theses and Dissertations

Autism spectrum disorder (ASD) is a long-standing mental condition characterized by hindered mental growth and development. In 2018, 168 out of 10,000 children are said to be affected with Autism in the USA. As these children move to adulthood, they have difficulty in communicating with others, expressing themselves, maintaining eye contact, developing a well-functioning motor skill or sensory sensitivity, and paying attention for longer period. Some of these abnormalities, however, can be gradually improved if they are treated appropriately during their adulthood. Studies have shown that people with ASD can enhance their social-interactive skills by playing video games. During the …


Hydrological And Paleoclimate Analysis Of A Pinyon-Juniper And Fen-Dominated Watershed On The Windy Ridge Mega-Landslide, Joel Frederick Barker Nov 2019

Hydrological And Paleoclimate Analysis Of A Pinyon-Juniper And Fen-Dominated Watershed On The Windy Ridge Mega-Landslide, Joel Frederick Barker

Theses and Dissertations

Water BudgetThis chapter documents the hydrologic analysis of a watershed within the Windy Ridge mega-landslide of Central Utah to (1) create a water budget and (2) place a quantitative limit on the magnitude of climatic changes documented by Shurtliff et al. (2017) and Hudson et al. (2019). (1) A water budget was calculated over the last four years using instrumentation and weather stations both within and surrounding the watershed, In terms of precipitation input, 85% is released by the evapotranspiration of the Pinyon-Juniper forest, 4% discharges as surface water from the base of the watershed, and 11 % infiltrates the …


Bifunctional Helical Peptide Catalysts For Enzyme-Like Reactivity And Selectivity And Selective Stapling Of Natural Amino Acid Residues With Hydrophilic Squaric Acid Derivatives, Michael James Kinghorn Oct 2019

Bifunctional Helical Peptide Catalysts For Enzyme-Like Reactivity And Selectivity And Selective Stapling Of Natural Amino Acid Residues With Hydrophilic Squaric Acid Derivatives, Michael James Kinghorn

Theses and Dissertations

Peptide secondary structure provides an exceptional scaffold on which to design highly reactive and selective enzyme-like catalysts. This work describes the rational design and synthesis of a suite of helical peptide catalysts that are capable of achieving proximity-induced rate enhancement in Diels-Alder cycloadditions and indole alkylations. Microwave assisted synthesis of resin-supported polypeptides enables incorporation of non-natural amino acid residues that induce helicity (Aib) or provide functional handles on which organic catalytic residues can be attached. These small peptide catalysts exhibit binding-driven selectivity rather than relying on the inherent reactivity of substrates, which allows access to products that are not obtainable …


Exploration Of Sputtered Thin Films—E.G., In Sample Preparation And Material Characterization, Tuhin Roychowdhury Oct 2019

Exploration Of Sputtered Thin Films—E.G., In Sample Preparation And Material Characterization, Tuhin Roychowdhury

Theses and Dissertations

My dissertation focuses on (i) the development sputtered films for solid phase microextraction (SPME) and (ii) the comprehensive characterization of materials using a suite of analytical techniques. Chapter 1 reviews the basics of SPME. This chapter also contains (i) a discussion of various sputtering techniques, (ii) a discussion of two techniques I focused on most of my work: spectroscopic ellipsometry (SE) and X-ray photoelectron spectroscopy (XPS). Chapter 2 focuses the major part of my work, which is to prepare new solid phases/adsorbents for SPME via silicon sputtering followed by thermal deposition of a polymer, polydimethylsiloxane (PDMS). PDMS was deposited by …


Making Sense Of The Equal Sign In Middle School Mathematics, Chelsea Lynn Dickson Oct 2019

Making Sense Of The Equal Sign In Middle School Mathematics, Chelsea Lynn Dickson

Theses and Dissertations

One of the main reasons that students struggle as they transition from arithmetic to algebra in the middle grades is that they fail to develop the appropriate understanding of the equal sign. Previous research has suggested that students need to move past an operational understanding and develop a relational understanding of the equal sign in order to work with algebraic equations successfully. Other research has suggested that the way that we interpret and utilize the equal sign is based on three main factors: multiple meanings of the equal sign, equation types, and structural conventions. This study extends both areas of …