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Articles 601 - 630 of 3436

Full-Text Articles in Physical Sciences and Mathematics

Mathematical Identities Of Students With Mathematics Learning Dis/Abilities, Emma Lynn Holdaway Jun 2020

Mathematical Identities Of Students With Mathematics Learning Dis/Abilities, Emma Lynn Holdaway

Theses and Dissertations

The majority of research on the mathematics teaching and learning of students with mathematics learning dis/abilities is not performed in the field of mathematics education, but in the field of special education. Due to this theoretical divide, students with mathematics learning dis/abilities are far more likely to be in classes that emphasize memorization, direct instruction, and the explicit teaching of rules and procedures. Additionally, students with mathematics learning dis/abilities are often seen as "unable" to succeed in school mathematics and are characterized by their academic difficulties and deficits. The negative assumptions, beliefs, and expectations resulting from ableistic practices in the …

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Using Group Affinity To Predict Community Formation In Social Networks, Joseph Leung Jun 2020

Using Group Affinity To Predict Community Formation In Social Networks, Joseph Leung

Undergraduate Honors Theses

A well-studied topic in network theory is detecting the communities found in real-world networks. Community detection is a technique to better understand the way in which small dense substructures appear in these networks. Such substructures can often tell important information about groups that form in such systems. A prominent feature of many networks is that they evolve over time, forming and dissolving new edges between different nodes that appear. In this thesis, we consider how we can use the community structure of a network at a certain point in time to predict the state of a network’s communities at some …

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Ambiguous Student Contributions And Teacher Responses To Clarifiable Ambiguity In Secondary Mathematics Classrooms, Alicia Marie Heninger Jun 2020

Ambiguous Student Contributions And Teacher Responses To Clarifiable Ambiguity In Secondary Mathematics Classrooms, Alicia Marie Heninger

Theses and Dissertations

Different types of ambiguous student contributions occur in mathematics classrooms. In this study I identified (1) different types of ambiguous student contributions and (2) the different ways teachers respond to one particular kind of ambiguous contribution, clarifiable ambiguity. Note that clarifiable ambiguity is ambiguity that stems from a student who uses an unclear referent in their contribution and can be clarified in the moment by the particular student. Literature has focused only on ambiguity that has the potential to further the development of mathematical concepts and has only theorized about teacher responses to this specific type of ambiguity. This study …

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Microfabricated Fluidic Devices For Biological Assays And Bioelectronics, Anna V. Bickham Jun 2020

Microfabricated Fluidic Devices For Biological Assays And Bioelectronics, Anna V. Bickham

Theses and Dissertations

Microfluidics miniaturizes many benchtop processes and provides advantages of low cost, reduced reagent usage, process integration, and faster analyses. Microfluidic devices have been fabricated from a wide variety of materials and methods for many applications. This dissertation describes four such examples, each employing different features and fabrication methods or materials in order to achieve their respective goals. In the first example of microfluidic applications in this dissertation, thermoplastics are hot embossed to form t-shaped channels for microchip electrophoresis. These devices are used to separate six preterm birth (PTB) biomarkers and establish a limit of detection for each. The next chapter …

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Divisors Of Modular Parameterizations Of Elliptic Curves, Jonathan Reid Hales Jun 2020

Divisors Of Modular Parameterizations Of Elliptic Curves, Jonathan Reid Hales

Theses and Dissertations

The modularity theorem implies that for every elliptic curve E /Q there exist rational maps from the modular curve X_0(N) to E, where N is the conductor of E. These maps may be expressed in terms of pairs of modular functions X(z) and Y(z) that satisfy the Weierstrass equation for E as well as a certain differential equation. Using these two relations, a recursive algorithm can be constructed to calculate the q - expansions of these parameterizations at any cusp. These functions are algebraic over Q(j(z)) and satisfy modular polynomials where each of the coefficient functions are rational functions in …

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Towards Cooperating In Repeated Interactions Without Repeating Structure, Huy Pham Jun 2020

Towards Cooperating In Repeated Interactions Without Repeating Structure, Huy Pham

Theses and Dissertations

A big challenge in artificial intelligence (AI) is creating autonomous agents that can interact well with other agents over extended periods of time. Most previously developed algorithms have been designed in the context of Repeated Games, environments in which the agents interact in the same scenario repeatedly. However, in most real-world interactions, relationships between people and autonomous agents consist of sequences of distinct encounters with different incentives and payoff structures. Therefore, in this thesis, we consider Interaction Games, which model interactions in which the scenario changes from encounter to encounter, often in ways that are unanticipated by the players. For …

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Student Use Of Mathematical Content Knowledge During Proof Production, Chelsey Lynn Van De Merwe Jun 2020

Student Use Of Mathematical Content Knowledge During Proof Production, Chelsey Lynn Van De Merwe

Theses and Dissertations

Proof is an important component of advanced mathematical activity. Nevertheless, undergraduates struggle to write valid proofs. Research identifies many of the struggles students experience with the logical nature and structure of proofs. Little research examines the role mathematical content knowledge plays in proof production. This study begins to fill this gap in the research by analyzing what role mathematical content knowledge plays in the success of a proof and how undergraduates use mathematical content knowledge during proofs. Four undergraduates participated in a series of task-based interviews wherein they completed several proofs. The interviews were analyzed to determine how the students …

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Abstractions Of Graph Models, Charles Addison Johnson Jun 2020

Abstractions Of Graph Models, Charles Addison Johnson

Theses and Dissertations

Building models, whether to explain or to predict observed data, is an exercise of describing how the values of observed variables depend on those of others. Black box models only describe relationships between observed variables, and they are evaluated by their ability to accurately describe the values of observed variables in new situations not previously available to the model–such as the output response to a new set of inputs, for example. Black box models describe the observed behavior of the underlying system, but they may not correctly describe the way in which the system computes this behavior. White box models, …

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Graph-Based Whole Genome Phylogenomics, Masaki Stanley Fujimoto Jun 2020

Graph-Based Whole Genome Phylogenomics, Masaki Stanley Fujimoto

Theses and Dissertations

Understanding others is a deeply human urge basic in our existential quest. It requires knowing where someone has come from and where they sit amongst peers. Phylogenetic analysis and genome wide association studies seek to tell us where we’ve come from and where we are relative to one another through evolutionary history and genetic makeup. Current methods do not address the computational complexity caused by new forms of genomic data, namely long-read DNA sequencing and increased abundances of assembled genomes, that are becoming evermore abundant. To address this, we explore specialized data structures for storing and comparing genomic information. This …

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A Study Of The Anthropogenic Impact In Farmington Bay Through Isotopic And Elemental Analysis, Nathan Vaun Gunnell Jun 2020

A Study Of The Anthropogenic Impact In Farmington Bay Through Isotopic And Elemental Analysis, Nathan Vaun Gunnell

Theses and Dissertations

The influence of human activity on surrounding environments is an important field of research. With respect to aquatic settings, lacustrine deposits provide excellent proxies of environmental change since the sediment accumulates at a relatively constant rate, recording environmental change. This study employs isotopic, mineral, and chemical records from Farmington Bay freeze cores, in particular δ13C, δ15N, and 210Pb isotopes as well as phosphorus level fluctuation and trace metal analysis. In particular, 210Pb isotopes permit estimation of the age of sediment with depth and δ15N, δ13C, and concentration of P provides a record of changing nutrient sources and level of eutrophication. …

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Synthesis Of Functionalized Streptococcus Pneumoniae Serotype 6a Di- And Tri- Saccharides, Brady Davis James May 2020

Synthesis Of Functionalized Streptococcus Pneumoniae Serotype 6a Di- And Tri- Saccharides, Brady Davis James

Theses and Dissertations

There is a rise in prevalence of antibiotic resistance in Streptococcus pneumoniae, and its FDA-approved vaccines often do not mount effective immune responses in children, the elderly, or the immunocompromised. One reason these vaccines are generally less effective is because they do not utilize T-cell help. T-cell help can be accessed when di-, tri-, or tetra-saccharides positioned inside major histocompatibility complex (MHC) II are presented to T-cell receptors as a target antigen. Pairing MHC II-antigen complexes with T-cell receptors enables development of B and T lymphocytes that are highly specific to these antigens, granting an increase in antibody affinity and …

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Topologically Mixing Suspension Flows, Jason J. Day May 2020

Topologically Mixing Suspension Flows, Jason J. Day

Theses and Dissertations

We find a set of conditions on a roof function to ensure topological mixing for suspension flows over a topological mixing base. In the measure theoretic case, such conditions have already been established for certain flows. Specifically, certain suspensions are topologically mixing if and only if the roof function is not cohomologous to a constant. We show that an analogous statement holds to establish topological mixing with the presence of dense periodic points. Much of the work required is to find properties specific to the equivalence class of functions cohomologous to a constant. In addition to these conditions, we show …

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On The Distribution Of Inter-Arrival Times Of 911 Emergency Responseprocess Events, Blake Cameron Moss May 2020

On The Distribution Of Inter-Arrival Times Of 911 Emergency Responseprocess Events, Blake Cameron Moss

Theses and Dissertations

The 911 emergency response process is a core component of the emergency services critical infrastructure sector in the United States. Modeling and simulation of a complex stochastic system like the 911 response process enables policy makers and stakeholders to better understand, identify, and mitigate the impact of attacks/disasters affecting the 911 system. Modeling the 911 response process as a series of queue sub-systems will enable analysis into how CI failures impact the different phases of the 911 response process. Before such a model can be constructed, the probability distributions of the inter-arrivals of events into these various sub-systems needs to …

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Geometric Extensions Of Neural Processes, Andrew Newberry Carr May 2020

Geometric Extensions Of Neural Processes, Andrew Newberry Carr

Theses and Dissertations

Neural Processes (NPs) are a class of regression models that learn a map from a set of input-output pairs to a distribution over functions. NPs are computationally tractable and provide a number of benefits over traditional nonlinear regression models. Despite these benefits, there are two main domains where NPs fail. This thesis is focused on presenting extensions of the Neural Process to these two areas. The first of these is the extension of Neural Processes graph and network data which we call Graph Neural Processes (GNP). A Graph Neural Process is defined as a Neural Process that operates on graph …

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Thin Film Deposition On Powder Substrates Using Ald And Its Characterization Using Xps, Tem, And Se, Dhruv Shah Apr 2020

Thin Film Deposition On Powder Substrates Using Ald And Its Characterization Using Xps, Tem, And Se, Dhruv Shah

Theses and Dissertations

The major part of my dissertation consists of thin films deposited using atomic layer deposition on flat and powder substrates. It details the various optimization experiments for process parameters like dose time, purge time, temperature, and pressure on silicon shards and powder substrates. Spectroscopic ellipsometry (SE) was used to characterize these films over a wide wavelength range (191-1688 nm). An optical model with a BEMA (Bruggeman effective medium approximation) layer was used to fit the ellipsometric data to investigate the optical properties of the alumina surface. The optimized process parameters on the flat surfaces were used for coating powder substrates. …

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Electrical Characterization And Annealing Of Dna Origami Templated Gold Nanowires, Tyler Richard Westover Apr 2020

Electrical Characterization And Annealing Of Dna Origami Templated Gold Nanowires, Tyler Richard Westover

Theses and Dissertations

DNA origami templates have been studied due the versatility of shapes that can be designed and their compatibility with various materials. This has potential for future electronic applications. This work presents studies performed on the electrical properties of DNA origami templated gold nanowires. Using a DNA origami tile, gold nanowires are site specifically attached in a “C” shape, and with the use of electron beam induced deposition of metal, electrically characterized. These wires are electrically conductive with resistivities as low as 4.24 x 10-5 Ω-m. During moderate temperature processing nanowires formed on DNA origami templates are shown to be affected …

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Organic Synthesis Using Bimetallic Catalysis, Chloe Christine Ence Apr 2020

Organic Synthesis Using Bimetallic Catalysis, Chloe Christine Ence

Theses and Dissertations

Bimetallic Catalysis is an emerging field of study that uses two metals to cooperatively perform organic transformations. These metals can serve to activate or bind substrates in order to increase the rate and selectivity of reactions. This work first describes the synthesis and utilization of six new chiral, titanium-containing phosphinoamide ligands. These Lewis acidic ligands withdraw electron density from an active palladium center to induce chirality and increase the rate of allylic amination of hindered, secondary N-alkyl amines. X-ray quality crystals were grown for each ligand and completed the allylic amination of hindered secondary amines in minutes whereas other non-titanium-containing …

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Comparative Genomics Using The Colored De Bruijn Graph, Cole Andrew Lyman Apr 2020

Comparative Genomics Using The Colored De Bruijn Graph, Cole Andrew Lyman

Theses and Dissertations

Comparing genomes in a computationally efficient manner is a difficult problem. Methods that provide the highest resolution are too inefficient and methods that are efficient are too low resolution. In this thesis, we show that the Colored de Bruijn Graph (CdBG) is a suitable method for comparing genomes because it is efficient while maintaining a useful amount of resolution. To illustrate the usefulness of the CdBG, the phylogenetic tree for 12 species in the Drosophila genus is reconstructed using pseudo-homologous regions of the genome contained in the CdBG.

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Superconductivity At Its Limit: Simulating Superconductor Dynamics Near The Superconducting Superheating Field In Eilenberger And Ginzburg-Landau Theory, Alden Roy Pack Apr 2020

Superconductivity At Its Limit: Simulating Superconductor Dynamics Near The Superconducting Superheating Field In Eilenberger And Ginzburg-Landau Theory, Alden Roy Pack

Theses and Dissertations

We computationally explore the dynamics of superconductivity near the superheating field in two ways. First, we use a finite element method to solve the time-dependent Ginzburg-Landau equations of superconductivity. We present a novel way to evaluate the superheating field Hsh and the critical mode that leads to vortex nucleation using saddle-node bifurcation theory. We simulate how surface roughness, grain boundaries, and islands of deficient Sn change those results in 2 and 3 spatial dimensions. We study how AC magnetic fields and heat waves impact vortex movement. Second, we use automatic differentiation to abstract away the details of deriving the equations …

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Chaotic Model Prediction With Machine Learning, Yajing Zhao Apr 2020

Chaotic Model Prediction With Machine Learning, Yajing Zhao

Theses and Dissertations

Chaos theory is a branch of modern mathematics concerning the non-linear dynamic systems that are highly sensitive to their initial states. It has extensive real-world applications, such as weather forecasting and stock market prediction. The Lorenz system, defined by three ordinary differential equations (ODEs), is one of the simplest and most popular chaotic models. Historically research has focused on understanding the Lorenz system's mathematical characteristics and dynamical evolution including the inherent chaotic features it possesses. In this thesis, we take a data-driven approach and propose the task of predicting future states of the chaotic system from limited observations. We explore …

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Supporting Support Engineers, Esdras Kutomi Apr 2020

Supporting Support Engineers, Esdras Kutomi

Theses and Dissertations

The steady and uninterrupted availability of systems is essential for the mission of many companies and other organizations. This responsibility relies mostly upon support engineers, who are responsible to respond to incidents. Incident response is a unique type of task in software engineering, given it carries distinguishing characteristics like risks, pressure, incomplete information and urgency. Despite the importance of this task for many organizations, little can be found in the literature about the incident response task and model. To fill the gap, we created a theoretical foundation to foster research on incident response. We conducted an interview study, asking 12 …

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Capillary Morphogenesis Gene Protein 2 (Cmg2) Mediates Matrix Protein Uptake And Is Required For Endothelial Cell Chemotaxis In Response To Multiple Vascular Growth Factors, Tsz Ming Jeremy Tsang Apr 2020

Capillary Morphogenesis Gene Protein 2 (Cmg2) Mediates Matrix Protein Uptake And Is Required For Endothelial Cell Chemotaxis In Response To Multiple Vascular Growth Factors, Tsz Ming Jeremy Tsang

Theses and Dissertations

Pathological angiogenesis, or new blood vessel formation, is involved in many pathologies, including cancer and serious eye diseases. While traditional anti-angiogenic therapies target vascular endothelial growth factor receptors to reduce or inhibit new vessel formation, this approach has several downsides, including unpleasant side effects and low efficacy over time. Therefore, identifying new targets to treat pathological angiogenesis is still needed. CMG2, one of the two identified anthrax toxin receptors, has been proposed as an alternative target to treat pathological angiogenesis. CMG2’s role as a cell surface receptor that mediates anthrax toxin internalization is very well documented. One physiological function for …

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Design, Synthesis, And Characterization Of New Non-Centrosymmetric Organic Crystals For Terahertz Generation, Gabriel Alejandro Valdivia-Berroeta Apr 2020

Design, Synthesis, And Characterization Of New Non-Centrosymmetric Organic Crystals For Terahertz Generation, Gabriel Alejandro Valdivia-Berroeta

Theses and Dissertations

Terahertz (THz) spectroscopy is an emerging technology with promising applications in imaging, homeland security, and material detection and quantification. Frequencies in the THz region can be generated by optical rectification of ultrafast near-infrared laser pulses in the presence of a nonlinear optical (NLO) materials such as organic crystals. Non-centrosymmetric organic THz generating crystals such as DAST, HMQ-TMS, and OH1 have received special attention due to the strong generated fields on the order of MV/cm. The cation of these organic salts is designed by connecting electron-donating with electron-accepting groups via a highly planar aromatic system. To improve the performance of organic …

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Stability Of Mhd Shock Waves, Bryn Nicole Barker Apr 2020

Stability Of Mhd Shock Waves, Bryn Nicole Barker

Theses and Dissertations

This thesis focuses on the study of spectral stability of planar shock waves in 2-dimensional magnetohydrodynamics. We begin with a numerical approach, computing the Lopatinski determinant and Evans function with the goal of determining if there are parameters for which viscous waves are unstable and the corresponding inviscid waves are stable. We also begin developing a method to obtain an explicit, analytical representation of the Evans function. We demonstrate the capabilities of this method with compressible Navier-Stokes and extend our results to 2-D MHD. Finally, using compressible Navier-Stokes again, we derive an energy estimate as a first step in improving …

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Bounds On Heat Transfer In The Presence Of Ekman Pumping, Benjamin Alexander Pachev Apr 2020

Bounds On Heat Transfer In The Presence Of Ekman Pumping, Benjamin Alexander Pachev

Theses and Dissertations

Rigorous bounds on heat transfer in rapidly rotating convection have existed for several years in the case of free-slip or stress-free boundary conditions. No-slip boundary conditions result in a phenomenon known as Ekman pumping, which significantly impacts the heat transport. A recent collaborative effort in which the author was involved significantly sharpened the bound on heat transfer in the presence of Ekman pumping. The resulting publication was targeted for an audience consisting primarily of physicists and other non-mathematicians. This work stems from the same effort, but is intended for a mathematical audience. Two additional, new results are presented that provide …

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Managing Two-Factor Authentication Setup Through Password Managers, Jonathan William Dutson Apr 2020

Managing Two-Factor Authentication Setup Through Password Managers, Jonathan William Dutson

Theses and Dissertations

Two-factor authentication (2FA) provides online accounts with protection against remote account compromise. Despite the security benefits, adoption of 2FA has remained low, in part due to poor usability. We explore the possibility of improving the usability of the 2FA setup process by providing setup automation through password managers. We create a proof-of-concept KeePass (a popular password manager) extension that adds browser-based automation to the 2FA setup process and conduct a 30-participant within-subjects user study to measure user perceptions about the system. Our system is found to be significantly more usable than the current manual method of 2FA setup for multiple …

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Growing Complex Networks For Better Learning Of Chaotic Dynamical Systems, David Joseph Passey Jr. Apr 2020

Growing Complex Networks For Better Learning Of Chaotic Dynamical Systems, David Joseph Passey Jr.

Theses and Dissertations

This thesis advances the theory of network specialization by characterizing the effect of network specialization on the eigenvectors of a network. We prove and provide explicit formulas for the eigenvectors of specialized graphs based on the eigenvectors of their parent graphs. The second portion of this thesis applies network specialization to learning problems. Our work focuses on training reservoir computers to mimic the Lorentz equations. We experiment with random graph, preferential attachment and small world topologies and demonstrate that the random removal of directed edges increases predictive capability of a reservoir topology. We then create a new network model by …

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Bountiful City Source Apportionment Study 2019, Jaron Hansen, Delbert Eatough Apr 2020

Bountiful City Source Apportionment Study 2019, Jaron Hansen, Delbert Eatough

ScholarsArchive Data

Quality assured data from air sampling campaign conducted in Bountiful City during February-June 2019.

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An Actuarial Approach To Personal Injury Protection Severity, Jason Colgrove Mar 2020

An Actuarial Approach To Personal Injury Protection Severity, Jason Colgrove

Undergraduate Honors Theses

Insurance companies examine the risk of financial losses for their policyholders as a way to accurately price insurance policies. Within the automobile insurance sector, the frequency of crashes and the associated liabilities started to increase in late 2013 when it had been on the decline for close to a decade. The purpose of this research focuses on the possible correlated variables that could lead to a better understanding of this change. To embark on this task, we teamed up with the Society of Actuaries, Casualty Actuarial Society, and the American Property Casualty Insurance Association to obtain data regarding frequency, severity, …

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Immobilization Of Copper Nanoparticles Onto Various Supports Applications In Catalysis, Anh Hoang Tu Nguyen Sorenson Mar 2020

Immobilization Of Copper Nanoparticles Onto Various Supports Applications In Catalysis, Anh Hoang Tu Nguyen Sorenson

Theses and Dissertations

Copper-based materials are one of the most promising catalysts for performing transformations of important organic compounds in both academic and industrial operations. However, it is challenging to consistently synthesize highly active and stable copper species as heterogeneous catalysts due to their relatively high surface energy. As a result, agglomeration usually occurs, which limits the catalytic activities of the copper species. The work presented in this dissertation shows different synthetic strategies for obtaining active and stable copper-based materials by modifying chemical/physical properties of copper nanoparticles (NPs). Emphasis is placed on discussing specific catalytic systems, including carbon-supported catalysts (monometallic and bimetallic copper-based …

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