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Articles 331 - 360 of 2906

Full-Text Articles in Physical Sciences and Mathematics

Dynamics Of Systems Driven By An External Force, Xue Liu Apr 2021

Dynamics Of Systems Driven By An External Force, Xue Liu

Theses and Dissertations

In this dissertation, we study the complicated dynamics of two classes of systems: Anosov systems driven by an external force and partially hyperbolic systems driven by an external force. For smooth Anosov systems driven by an external force, we first study the random specification property, which is on the approximation of an N−spaced arbitrary long finite random orbit segments within given precision by a random periodic point. We prove that if such system is topological mixing on fibers, then it has the random specification property. Furthermore, we prove that the homeomorphism induced by such a system on the space of …


Computing The Rank Of Braids, Justin Meiners Apr 2021

Computing The Rank Of Braids, Justin Meiners

Theses and Dissertations

We describe a method for computing rank (and determining quasipositivity) in the free group using dynamic programming. The algorithm is adapted to computing upper bounds on the rank for braids. We test our method on a table of knots by identifying quasipositive knots and calculating the ribbon genus. We consider the possibility that rank is not theoretically computable and prove some partial results that would classify its computational complexity. We then present a method for effectively brute force searching band presentations of small rank and conjugate length.


Going For Gold: Point Of Care Bio-Diagnostics And Gold Nanoparticles Treating Disease, Trevor M. Godfrey Apr 2021

Going For Gold: Point Of Care Bio-Diagnostics And Gold Nanoparticles Treating Disease, Trevor M. Godfrey

Theses and Dissertations

Correct diagnosis of disease is essential in the effort to save and improve lives. Point of care (POC) diagnostics are in-vitro tests that assist in patient diagnosis and can be used at the location of patient care. POC diagnostics are easy to use and provide near-instant readouts allowing medical providers and patients to make rapid decisions about treatment. Increased access to POC testing is especially beneficial to low-income and low resource areas that cannot afford expensive lab testing. The World Health Organization (WHO) has outlined at least 113 diseases for which POC diagnostics are needed. Because of this, developing effective, …


Improving Artistic Workflows For Fluid Simulation Through Adaptive And Editable Fluid Simulation Techniques, Sean A. Flynn Apr 2021

Improving Artistic Workflows For Fluid Simulation Through Adaptive And Editable Fluid Simulation Techniques, Sean A. Flynn

Theses and Dissertations

As the fidelity of computer generated imagery has increased, the need to digitally create convincing natural phenomena like fluids has become fundamental to the entertainment production industry. Because fluids are complex, the underlying physics must be computationally simulated. However, because a strictly physics-based approach is both computationally expensive and difficult to control, it does not lend itself well to the way artists and directors like to work. Directors require control to achieve their specific artistic vision. Furthermore, artistic workflows rely on quick iteration and the ability to apply changes late in the production process. In this dissertation we present novel …


Multilattice Tilings And Coverings, Joshua Randall Linnell Apr 2021

Multilattice Tilings And Coverings, Joshua Randall Linnell

Theses and Dissertations

Let L be a discrete subgroup of \mathbb{R}^n under addition. Let D be a finite set of points including the origin. These two sets will define a multilattice of \mathbb{R}^n. We explore how to generate a periodic covering of the space \mathbb{R}^n based on L and $D$. Additionally, we explore the problem of covering when we restrict ourselves to covering \mathbb{R}^n using only dilations of the right regular simplex in our covering. We show that using a set D= {0,d} to define our multilattice the minimum covering density is 5-\sqrt{13}. Furthermore, we show that when we allow for an arbitrary …


The Dns Bake Sale: Advertising Dns Cookie Support For Ddos Protection, Jacob Davis Apr 2021

The Dns Bake Sale: Advertising Dns Cookie Support For Ddos Protection, Jacob Davis

Theses and Dissertations

The Domain Name System (DNS) has been frequently abused for Distributed Denial of Service (DDoS) attacks and cache poisoning because it relies on the User Datagram Protocol (UDP). Since UDP is connection-less, it is trivial for an attacker to spoof the source of a DNS query or response. DNS Cookies, a protocol standardized in 2016, add pseudo-random values to DNS packets to provide identity management and prevent spoofing attacks. This work finds that 30% of popular authoritative servers and open recursive resolvers fully support cookies and that 10% of recursive clients send cookies. Despite this, DNS cookie use is rarely …


Fourier Decompositions Of Graphs With Symmetries And Equitable Partitions, Darren Scott Lund Mar 2021

Fourier Decompositions Of Graphs With Symmetries And Equitable Partitions, Darren Scott Lund

Theses and Dissertations

We show that equitable partitions, which are generalizations of graph symmetries, and Fourier transforms are fundamentally related. For a partition of a graph's vertices we define a Fourier similarity transform of the graph's adjacency matrix built from the matrices used to carryout discrete Fourier transformations. We show that the matrix (graph) decomposes into a number of smaller matrices (graphs) under this transformation if and only if the partition is an equitable partition. To extend this result to directed graphs we define two new types of equitable partitions, equitable receiving and equitable transmitting partitions, and show that if a partition of …


Light And Truth: Measuring Unseen Harm In Individuals And Communities, Hannah Pfost Mar 2021

Light And Truth: Measuring Unseen Harm In Individuals And Communities, Hannah Pfost

Undergraduate Honors Theses

While the fields of physics and international development may seem disparate, the insights gained from studying each one of them can improve understanding of the other. Here, I demonstrate that concept as applied to computational optics and historical memory. Thus, the purpose of this project is threefold: (1) to computationally model light transport through tissue, and use that model to inform choices about a physical system; (2) to determine the types of historical memory recommended in the final reports of truth commissions; and (3) to give evidence for the usefulness of human-centered design in both areas. To model light transport, …


Terwilliger Algebras For Several Finite Groups, Nicholas Lee Bastian Mar 2021

Terwilliger Algebras For Several Finite Groups, Nicholas Lee Bastian

Theses and Dissertations

In this thesis, we will explore the structure of Terwilliger algebras over several different types of finite groups. We will begin by discussing what a Schur ring is, as well as providing many different results and examples of them. Following our discussion on Schur rings, we will move onto discussing association schemes as well as their properties. In particular, we will show every Schur ring gives rise to an association scheme. We will then define a Terwilliger algebra for any finite set, as well as discuss basic properties that hold for all Terwilliger algebras. After specializing to the case of …


Telsam-Target Protein Fusions Can Form Diffraction-Quality Crystals Without Direct Inter-Polymer Contacts, Moriah Longhurst Mar 2021

Telsam-Target Protein Fusions Can Form Diffraction-Quality Crystals Without Direct Inter-Polymer Contacts, Moriah Longhurst

Undergraduate Honors Theses

X-ray diffraction is a robust method for determining the detailed 3D structures of specific proteins. However, this requires the formation of well-ordered protein crystals, a process that is time-consuming, expensive, and only has about a 10-30% success rate. New methods are needed to enable the efficient crystallization of challenging proteins. One such technique is explored here, which utilizes a protein polymer (the sterile alpha motif domain of the human protein translocation Ets leukemia, or TELSAM) as a crystallization chaperone to form a more ordered crystal lattice of target proteins and drive crystallization. This method was successfully used to crystallize, collect …


Realium: Building The Future Of Real Estate On The Blockchain, Demitri Haddad Mar 2021

Realium: Building The Future Of Real Estate On The Blockchain, Demitri Haddad

Undergraduate Honors Theses

This paper discusses the prospective challenges, limitations and opportunities in the real estate sector for blockchain. It outlines the idea of Realium, a financial technology application that aims to assist in the purchase, sale, and legal compliance of real estate assets. For more information see docs.realium.io


Computational Development Of A Miniature Quantum Dot Spectrometer For Use In Space, Joseph Richardson Mar 2021

Computational Development Of A Miniature Quantum Dot Spectrometer For Use In Space, Joseph Richardson

Undergraduate Honors Theses

Miniature spectrometers are of great interest to NASA as necessary instrumentation is scaled down and optimized for specific space application. Semiconductor nanocrystals called quantum dots (QD) are being used to create a miniature high-resolution filter-based spectrometer, with the goal of use in space within 5 years. Computational imaging techniques— such as automated image analysis and mathematical spectrum reconstruction algorithms—are key to making the QD spectrometer a reality. This thesis will discuss the process of developing these computational methods, along with the improvements that have occurred from previous work.


The Communicative Effects Of Anonymity Online: A Natural Language Analysis Of The Faceless, Caleb Johnson Mar 2021

The Communicative Effects Of Anonymity Online: A Natural Language Analysis Of The Faceless, Caleb Johnson

Undergraduate Honors Theses

An ever-increasing number of Americans have an active social media

presence online. As of March 2020, an estimated 79% of Americans were active

monthly users of some sort. Many of these online platforms allow users to

operate anonymously which could potentially lead to shifts in communicative

behavior. I first discuss my compilation process of the Twitter Anonymity

Dataset (TAD), a human-classified dataset of 100,000 Twitter accounts that are

categorized by their level of identifiability to their real-world agent. Next, I

investigate some of the structural differences between the classification levels

and employ a variety of Natural Language Processing models and …


Mean Square Displacement For A Discrete Centroid Model Of Cell Motion And A Mathematical Analysis Of Focal Adhesion Lifetimes And Their Effect On Cell Motility, Mary Ellen Furner Rosen Feb 2021

Mean Square Displacement For A Discrete Centroid Model Of Cell Motion And A Mathematical Analysis Of Focal Adhesion Lifetimes And Their Effect On Cell Motility, Mary Ellen Furner Rosen

Theses and Dissertations

One of the characteristics that distinguishes living things from non-living things is motility. On the cellular level, the motility or non-motility of different types of cells can be life building, life-saving or life-threatening. A thorough study of cell motion is needed to help understand the underlying mechanisms that enhance or prohibit cell motion. We introduce a discrete centroid model of cell motion in the context of a generalized random walk. We find an approximation for the theoretical mean square displacement (MSD) that uses a subset of the state space to estimate the MSD for the entire space. We give some …


Mean Square Displacement For A Discrete Centroid Model Of Cell Motion And A Mathematical Analysis Of Focal Adhesion Lifetimes And Their Effect On Cell Motility, Mary Ellen Furner Rosen Feb 2021

Mean Square Displacement For A Discrete Centroid Model Of Cell Motion And A Mathematical Analysis Of Focal Adhesion Lifetimes And Their Effect On Cell Motility, Mary Ellen Furner Rosen

Theses and Dissertations

One of the characteristics that distinguishes living things from non-living things is motility. On the cellular level, the motility or non-motility of different types of cells can be life building, life-saving or life-threatening. A thorough study of cell motion is needed to help understand the underlying mechanisms that enhance or prohibit cell motion. We introduce a discrete centroid model of cell motion in the context of a generalized random walk. We find an approximation for the theoretical mean square displacement (MSD) that uses a subset of the state space to estimate the MSD for the entire space. We give some …


Sp2 Bonded Carbon For Soft X-Ray Detector Windows, Joseph T. Rowley Jan 2021

Sp2 Bonded Carbon For Soft X-Ray Detector Windows, Joseph T. Rowley

Theses and Dissertations

Energy Dispersive X-Ray Spectroscopy (EDS) is a technique used to analyze materials to determine their elemental makeup. This technique is used extensively in the semiconductor industry, metallurgical industry, biology, chemistry, materials science, and other fields. EDS detectors are often attached to scanning electron microscopes (SEM) or transmission electron microscopes (TEM) and are actively cooled by liquid nitrogen or Peltier devices. A thin membrane, or window, is fitted to the front of the detector which allows for an airtight seal as well as transmission of x-rays. The challenge for these windows is maximizing the transmission of x-rays while maintaining mechanical integrity. …


The "What"-"Where" Network: A Tool For One-Shot Image Recognition And Localization, Daniel Hurlburt Jan 2021

The "What"-"Where" Network: A Tool For One-Shot Image Recognition And Localization, Daniel Hurlburt

Theses and Dissertations

One common shortcoming of modern computer vision is the inability of most models to generalize to new classes—one/few shot image recognition. We propose a new problem formulation for this task and present a network architecture and training methodology to solve this task. Further, we provide insights into how careful focus on how not just the data, but the way data presented to the model can have significant impact on performance. Using these method, we achieve high accuracy in few-shot image recognition tasks.


The Nabataean Façade Monuments Of Petra, Jordan: An Assessment Of The Façade Monuments And Their Geological Environment., Josie M. Newbold Jan 2021

The Nabataean Façade Monuments Of Petra, Jordan: An Assessment Of The Façade Monuments And Their Geological Environment., Josie M. Newbold

Theses and Dissertations

The Nabataean people controlled the Petra region of modern-day Jordan from sometime before 300 BCE until the Roman Annexation of the Nabataean kingdom in 106 CE. The Nabataeans are known for the monumental façades carved into the sandstone cliffs surrounding their capital city. The first survey of the façade monuments was undertaken by Brünnow and Domaszewski in 1904. They created a typology that has only been slightly modified by subsequent authors including Judith McKenzie (1990). This typology does not account for all of the variations in façade types in Petra, thus creating a need for a new typology proposed in …


Improvement In 14-3-3 Binding Site Prediction, Katherine K. Mccormack Jan 2021

Improvement In 14-3-3 Binding Site Prediction, Katherine K. Mccormack

ScholarsArchive Data

The 14-3-3 family of phospho-binding proteins regulate a variety of major cellular processes through interaction with a network of dynamic proteins. Deregulation of the 14-3-3 interaction network contributes to a variety of degenerative disorders and cancers. Our lab focuses on identifying novel 14-3-3 interactions and understanding how 14-3-3 binding regulates protein function. A major gap in this process is that identifying the phospho-site where 14-3-3 docks on a given protein is time- and resource-consuming. Prediction algorithms have been developed to predict canonical 14-3-3 binding sites, however, there are many non-canonical sites that existing software is unable to predict. To fill …


Modeling Continental-Scale Outdoor Environmental Sound Levels With Limited Data, Katrina Lynn Pedersen Jan 2021

Modeling Continental-Scale Outdoor Environmental Sound Levels With Limited Data, Katrina Lynn Pedersen

Theses and Dissertations

Modeling outdoor acoustic environments is a challenging problem because outdoor acoustic environments are the combination of diverse sources and propagation effects, including barriers to propagation such as buildings or vegetation. Outdoor acoustic environments are most commonly modeled on small geographic scales (e.g., within a single city). Extending modeling efforts to continental scales is particularly challenging due to an increase in the variety of geographic environments. Furthermore, acoustic data on which to train and validate models are expensive to collect and therefore relatively limited. It is unclear how models trained on this limited acoustic data will perform across continental-scales, which likely …


In Vitro Screening Of Tp5801 Against Kinases For Nature Communications Publication, Joshua Andersen Jan 2021

In Vitro Screening Of Tp5801 Against Kinases For Nature Communications Publication, Joshua Andersen

ScholarsArchive Data

Data from screen of TP-5801 against in vitro kinases


Kinase Screen Data For Nature Communications Publication, Joshua Andersen Jan 2021

Kinase Screen Data For Nature Communications Publication, Joshua Andersen

ScholarsArchive Data

A TNK1 peptide encompassing S502 was screened against 245 Ser/Thr kinases. This file contains kinase activity values (against S502) from an n=1 experiment. These data support a manuscript to be published in Nature Communications (Chan and Egbert et al.)


Sources Of Formaldehyde In Bountiful Ut Data, Nitish Bhardwaj, Ariel Kelsch, Delbert Eatough, Ryan Thalman, Nancy Daher, Kerry Kelly, Isabel Cristina Jaramillo, Jaron Hansen Jan 2021

Sources Of Formaldehyde In Bountiful Ut Data, Nitish Bhardwaj, Ariel Kelsch, Delbert Eatough, Ryan Thalman, Nancy Daher, Kerry Kelly, Isabel Cristina Jaramillo, Jaron Hansen

ScholarsArchive Data

Source of Formaldehyde in Bountiful, UT Data

This file contains the X and U matrix used in the positive matrix factorization analysis done on the data collected in Bountiful, UT. The X matrix contains the concentration of species measured and the U matrix is the calculated uncertainty in each measured value. This data is stored in the Excel format.

Included in this file is the two-hour averaged concentrations of formaldehyde and ozone, wind direction, time of day, and date that the data was collected at the Bountiful, UT air sampling site located at the Bountiful Utah High School. This data …


Leveraging The Inductive Bias Of Large Language Models For Abstract Textual Reasoning, Christopher Michael Rytting Dec 2020

Leveraging The Inductive Bias Of Large Language Models For Abstract Textual Reasoning, Christopher Michael Rytting

Theses and Dissertations

Large natural language models (such as GPT-2 or T5) demonstrate impressive abilities across a range of general NLP tasks. Here, we show that the knowledge embedded in such models provides a useful inductive bias, not just on traditional NLP tasks, but also in the nontraditional task of training a symbolic reasoning engine. We observe that these engines learn quickly and generalize in a natural way that reflects human intuition. For example, training such a system to model block-stacking might naturally generalize to stacking other types of objects because of structure in the real world that has been partially captured by …


A Water Budget And Solute Flux Budget For Waimea River Watershed, Kauai, Hi, U.S.A., Joseph Harold Tolworthy Dec 2020

A Water Budget And Solute Flux Budget For Waimea River Watershed, Kauai, Hi, U.S.A., Joseph Harold Tolworthy

Theses and Dissertations

Waimea Canyon is a deep V-shaped canyon on the island of Kauai, Hawaii in which the Waimea River and its tributaries flow. The shape and size of the canyon are noteworthy and unusual compared to its contemporary canyons on the Hawaiian Islands which are usually U-shaped or flat bottomed. This could be because there is significantly more physical erosion in Waimea Canyon compared to others. A water budget was created using ArcGIS Pro and data from the University of Hawaii’s rainfall and evapotranspiration atlases, as well as from the United States Geological Survey’s stream gage data. A mass flux was …


Nature And Origin Of The East Traverse Mountains Mega-Landslide, Northern Utah (Usa), Rodney Ryan Chadburn Dec 2020

Nature And Origin Of The East Traverse Mountains Mega-Landslide, Northern Utah (Usa), Rodney Ryan Chadburn

Theses and Dissertations

The East Traverse Mountains are an E-W trending mountain range dividing Utah and Salt Lake valleys in northern Utah. Geologically perplexing, the nature of the East Traverse Mountains has been under investigation for 140 years. Previously, the mountain range was proposed to be a dismembered but still coherent down-faulted block that experienced 4 km of post-thrusting extension within the Charleston-Nebo thrust sheet. However, new insight on the origin of the East Traverse Mountains indicate that it is a mega landslide, roughly ~100 km3 in size, which catastrophically slid from the upper reaches of the Little-Cottonwood stock to its present-day location. …


Instrumentation And Application Of Image-Charge Detection Of Electrospray-Charged Microparticles And Microdroplets, Jiuzhi Gao Dec 2020

Instrumentation And Application Of Image-Charge Detection Of Electrospray-Charged Microparticles And Microdroplets, Jiuzhi Gao

Theses and Dissertations

Image-charge detection is emerging as an important tool to analyze heavy and heterogeneous samples because of its unique advantages in measuring highly charged microparticles. Conventional image-charge detection instruments include at least three fundamental components: an ionization source, an aerodynamic particle delivery system, and an image-charge detector. Here I report research efforts that investigated the mechanisms of image-charge detection and proposed some instrumental developments of these components to suit specific research purposes. In Chapter 2, I report an investigation of the electrospray ionization (ESI) mechanism based on an observation that a certain portion of charged particles generated with an ESI source …


Methods For Generative Adversarial Output Enhancement, Michael B. Brodie Dec 2020

Methods For Generative Adversarial Output Enhancement, Michael B. Brodie

Theses and Dissertations

Generative Adversarial Networks (GAN) learn to synthesize novel samples for a given data distribution. While GANs can train on diverse data of various modalities, the most successful use cases to date apply GANs to computer vision tasks. Despite significant advances in training algorithms and network architectures, GANs still struggle to consistently generate high-quality outputs after training. We present a series of papers that improve GAN output inference qualitatively and quantitatively. The first chapter, Alpha Model Domination, addresses a related subfield of Multiple Choice Learning, which -- like GANs -- aims to generate diverse sets of outputs. The next chapter, CoachGAN, …


Structures And Characteristics Of Macromolecular Interactions In Gas Phase Using Fourier-Transform Ion Cyclotron Resonance Mass Spectrometry, Jiewen Shen Dec 2020

Structures And Characteristics Of Macromolecular Interactions In Gas Phase Using Fourier-Transform Ion Cyclotron Resonance Mass Spectrometry, Jiewen Shen

Theses and Dissertations

This dissertation investigates non-covalent macromolecular chemistry using Fourier transform ion cyclotron resonance mass spectrometry (FTICR-MS) based techniques. The included studies reveal the impact of molecular structure on conformation and binding energetics. Supramolecules that might be too heavy to be dissociated in single collision-induced dissociation (CID) were dissociated using sustained off-resonance collision induced dissociation (SORI-CID) techniques. Relative binding energies and thresholds were evaluated for various macromolecular host-guest systems. Besides the non-covalent binding energies, conformation characterization was undertaken by a novel method to determine collision cross sectional areas using FTICR (CRAFTI, and multi-CRAFTI), initially developed by the Dearden lab. The systems chosen …


Eigenvalues Of Differential Operators And Nontrivial Zeros Of L-Functions, Dongsheng Wu Dec 2020

Eigenvalues Of Differential Operators And Nontrivial Zeros Of L-Functions, Dongsheng Wu

Theses and Dissertations

The Hilbert-P\'olya conjecture asserts that the non-trivial zeros of the Riemann zeta function $\zeta(s)$ correspond (in a certain canonical way) to the eigenvalues of some positive operator. R. Meyer constructed a differential operator $D_-$ acting on a function space $\H$ and showed that the eigenvalues of the adjoint of $D_-$ are exactly the nontrivial zeros of $\zeta(s)$ with multiplicity correspondence. We follow Meyer's construction with a slight modification. Specifically, we define two function spaces $\H_\cap$ and $\H_-$ on $(0,\infty)$ and characterize them via the Mellin transform. This allows us to show that $Z\H_\cap\subseteq\H_-$ where $Zf(x)=\sum_{n=1}^\infty f(nx)$. Also, the differential operator …