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Full-Text Articles in Physical Sciences and Mathematics

Using Bayesian Networks To Provide Educational Implications: Mobile Learning And Ethnomathematics To Improve Sustainability In Mathematics Education, Jason D. Johnson, Linda Smail, Darryl Corey, Adeeb M. Jarrah May 2022

Using Bayesian Networks To Provide Educational Implications: Mobile Learning And Ethnomathematics To Improve Sustainability In Mathematics Education, Jason D. Johnson, Linda Smail, Darryl Corey, Adeeb M. Jarrah

All Works

There are many Western apps that help students strengthen their mathematics skills through learning and game apps. A research project was designed to create an IOS Math App to provide Grade 6 Emirati students with the opportunity to explore mathematics, then, using Bayesian Networks, to examine the educational implications. The learning app was developed using ethnomathematics modules based on the Emirati culture. Students were required to navigate through several modules to examine various mathematical concepts in algebra and geometry. The survey was written for Grade 6 English language learners. Based on the Bayesian Networks, the findings suggested that if students …


A Monte Carlo Method For Evaluating Empirical Gyrochronology Models And Its Application To Wide Binary Benchmarks, Tomomi Otani, Ted Von Hippel, Derek Buzasi, Terry Oswalt, Alexander Stone-Martinez, Patrice Majewski May 2022

A Monte Carlo Method For Evaluating Empirical Gyrochronology Models And Its Application To Wide Binary Benchmarks, Tomomi Otani, Ted Von Hippel, Derek Buzasi, Terry Oswalt, Alexander Stone-Martinez, Patrice Majewski

Publications

No abstract provided.


New Debiasing Strategies In Collaborative Filtering Recommender Systems: Modeling User Conformity, Multiple Biases, And Causality., Mariem Boujelbene May 2022

New Debiasing Strategies In Collaborative Filtering Recommender Systems: Modeling User Conformity, Multiple Biases, And Causality., Mariem Boujelbene

Electronic Theses and Dissertations

Recommender Systems are widely used to personalize the user experience in a diverse set of online applications ranging from e-commerce and education to social media and online entertainment. These State of the Art AI systems can suffer from several biases that may occur at different stages of the recommendation life-cycle. For instance, using biased data to train recommendation models may lead to several issues, such as the discrepancy between online and offline evaluation, decreasing the recommendation performance, and hurting the user experience. Bias can occur during the data collection stage where the data inherits the user-item interaction biases, such as …


Development And Novel Applications Of Halogenating Agents., Sagar Ravso Mudshinge May 2022

Development And Novel Applications Of Halogenating Agents., Sagar Ravso Mudshinge

Electronic Theses and Dissertations

Organic halides are extensively utilized as synthetic intermediates in areas such as pharmaceuticals, agrochemicals, and material polymers. While many halogenating agents have been developed, they continue to have low efficiency or selectivity, are difficult to handle, and often have limited substrate scope. To address this issue, our laboratory has developed novel halogenating agents with improved stability and efficiency. In these studies, we demonstrated a novel application of halogenating reagent, HCl·DMPU, in the nitrile synthesis. We developed a novel method for C−SCF3/SeCF3 cross-coupling reactions using gold redox catalysis. We developed a novel trifluoromethylating agent in a cost-effective and …


Fabrication Of Mof Films Of Uio Or Pcn Type Through Layer-By-Layer Molecular Deposition As Well As Bulk Deposition For Catalytic Applications, John Ozdemir May 2022

Fabrication Of Mof Films Of Uio Or Pcn Type Through Layer-By-Layer Molecular Deposition As Well As Bulk Deposition For Catalytic Applications, John Ozdemir

Graduate Theses and Dissertations

Metal-organic frameworks (MOFs) are crystalline, porous materials comprised of symmetric organic linkers coordinated to positively charged metal atoms or metal oxide nodes. This dissertation uses strategies in crystal engineering to advance the study of functional MOFs with emphasis on thin film deposition. The first chapter of this dissertation will introduce the field of reticular chemistry to the reader and describe synthetic efforts to develop useful building blocks for MOF materials: namely porphyrin macrocycles and carboxylate capped zirconium-oxo and hafnium-oxo clusters. The building blocks for MOFs developed in the first chapter will be employed in the second and third chapters through …


Reconstructing Bison And Mammoth Migration During The Late Pleistocene And Early Holocene Of Central Texas Using Strontium Isotopes, Joshua John Porter May 2022

Reconstructing Bison And Mammoth Migration During The Late Pleistocene And Early Holocene Of Central Texas Using Strontium Isotopes, Joshua John Porter

Graduate Theses and Dissertations

During the Late Pleistocene (LP; past 130,000 years), over two-thirds of large mammal (>45kg) species went extinct globally. While the role of humans is hotly debated, the effect of these extinctions is growing clearer; the extinctions resulted in widespread and lasting faunal community reorganization. However, the impact of these extinctions on dietary and migratory behavior within faunal communities is unknown. Our study examines the impact of the megafaunal extinctions on the dietary and migratory behavior of surviving Bison individuals in Texas using carbon, oxygen, and strontium isotopes. Strontium isotopes are incorporated into mammalian enamel during their tooth development and …


Understanding Interfacial Reactions Initiating On Electrode Materials For Energy Storage Technologies, Jingnan Li May 2022

Understanding Interfacial Reactions Initiating On Electrode Materials For Energy Storage Technologies, Jingnan Li

Graduate Theses and Dissertations

Since the first generation of lithium-ion batteries featured lithium cobalt oxide cathode and carbon anode commercialized in the 1990s, the high-capacity materials with lower cost are in demand to further increase the battery energy density. Lithium metal and silicon anode are promising high-capacity anode materials to achieve next-generation lithium batteries. However, both the materials actively react in electrolytes and suffer from dramatic volume change. Therefore, a reliable passivation layer at the electrolyte/electrode interphase (i.e., solid electrolyte interphase, or “SEI”) is required to support the long-term cycling of both materials. Cetrimonium hydro fluoride (CTAHF2) has been proposed and synthesized as an …


Stop And Smell The Fractals: An Exploration Into Math, Poetry, And Everything In Between, Caroline Jennings May 2022

Stop And Smell The Fractals: An Exploration Into Math, Poetry, And Everything In Between, Caroline Jennings

English Undergraduate Honors Theses

Stop and Smell The Fractals is a collection of poetry written during my time at The University of Arkansas. These poems highlight the connections between mathematics and poetry, focusing particularly on their emergence in everyday life.


The Use Of Hallucinogens In The Treatment Of Mental Health Disorders, Brianna Gagen May 2022

The Use Of Hallucinogens In The Treatment Of Mental Health Disorders, Brianna Gagen

Honors College Theses

The percent of people with mental health disorders in the United States have skyrocketed over the past decade. With stigma surrounding the discussion of mental health and the symptoms associated with it, often those that are suffering do not receive sufficient treatment, as they might with a physical illness. The current, common treatment options for common psychological disorders, like depression, anxiety, and post-traumatic stress disorder, are sometimes not effective in patients, due to resistance or poor response outcomes. Consequently, in order to research alternative therapeutic approaches for mental health disorders, scientists are researching the effects of several hallucinogenic drugs in …


The Butterfly Effect Of Fractals, Cody Watkins May 2022

The Butterfly Effect Of Fractals, Cody Watkins

Honors College Theses

This thesis applies concepts in fractal geometry to the relatively new field of mathematics known as chaos theory, with emphasis on the underlying foundation of the field: the butterfly effect. We begin by reviewing concepts useful for an introduction to chaos theory by defining terms such as fractals, transformations, affine transformations, and contraction mappings, as well as proving and demonstrating the contraction mapping theorem. We also show that each fractal produced by the contraction mapping theorem is unique in its fractal dimension, another term we define. We then show and demonstrate iterated function systems and take a closer look at …


Determining The Value Of Ecosystem Services Provided By Green Stormwater Infrastructure In Coastal South Carolina, Joan U. Ureta May 2022

Determining The Value Of Ecosystem Services Provided By Green Stormwater Infrastructure In Coastal South Carolina, Joan U. Ureta

All Dissertations

Rapid urbanization changes the natural hydrology of a landscape, making stormwater management a crucial aspect of land development. As the fastest growing ecosystem globally, an innovative way of managing stormwater is needed to address the increase in urban run-off. In coastal South Carolina, stormwater practices have been widely adopted at the neighborhood level, yet threat of flooding is becoming more evident as the urban population and development continue to rise.

To determine the importance of stormwater practices to coastal residents, we assessed perception on stormwater practices and programs at different decision levels— 1) household, 2) neighborhood, and 3) city/county. Results …


Synthesis Of Fluorinated Monomers And Polymers For Various Applications, Cassandra J. Hager May 2022

Synthesis Of Fluorinated Monomers And Polymers For Various Applications, Cassandra J. Hager

All Dissertations

The world of industry utilizes a variety of polymers for various applications in many prominent fields. From electronics to food storage, the versatility of this class of chemistry has been widely proven. The Thrasher research group undertook a program dedicated towards the development of a library of fluorinated materials that focused on the synthesis and characterization of perfluoroalkoxy (PFA) copolymers of tetrafluoroethylene (TFE) and perfluoroalkyl trifluorovinyl ethers. One aim of the project was to improve upon the mechanical strength and wearability of commercial PFA resins by incorporating bulkier perfluoroalkoxy trifluorovinyl ether monomers into these copolymers. In addition to focusing on …


Supertertiary Structural Dynamics Modulate Function In Postsynaptic Density Protein 95, George L. Hamilton Iii May 2022

Supertertiary Structural Dynamics Modulate Function In Postsynaptic Density Protein 95, George L. Hamilton Iii

All Dissertations

Proteins, RNA, and DNA serve as the primary sub-cellular machinery that give rise to the necessary functions of life. The long-standing paradigm has been that the structures of biomolecules, or the arrangement of the subunits that make up a biomolecule, determine biological function. However, biomolecules are not static objects. Instead, they often undergo structural rearrangements that are crucial to enabling and regulating their functions. In my thesis I present several studies of the interplay between the structures, dynamics, and functions of biomolecules that combine experimental fluorescence spectroscopy and computational methods to probe these systems at the single-molecule level. In particular, …


Exploring The Glow Of The Universe In Gamma-Rays And Hunting Distant Agn, Changam Meenakshi Rajagopal May 2022

Exploring The Glow Of The Universe In Gamma-Rays And Hunting Distant Agn, Changam Meenakshi Rajagopal

All Dissertations

The entirety of the γ-ray radiation permeating our Universe is encoded in the extragalactic γ-ray background. This is a superposition of resolved sources, mostly powerful relativistic jets powered by supermassive black holes, i.e., blazars, and an unresolved isotropic component, aka, the diffuse isotropic gamma-ray background (IGRB). Studying the IGRB can help unveil its composition, as well as unearth multi-messenger relationships between the intensities of PeV neutrinos, ultra high energy cosmic rays (> 1018 eV), and sub-TeV γ-rays. The comparable energy budgets of these three phenomena (neutrinos, UHECR, and γ-rays) indicates a physical connection or a common source amongst them. On …


Penalized Estimation Of Autocorrelation, Xiyan Tan May 2022

Penalized Estimation Of Autocorrelation, Xiyan Tan

All Dissertations

This dissertation explored the idea of penalized method in estimating the autocorrelation (ACF) and partial autocorrelation (PACF) in order to solve the problem that the sample (partial) autocorrelation underestimates the magnitude of (partial) autocorrelation in stationary time series. Although finite sample bias corrections can be found under specific assumed models, no general formulae are available. We introduce a novel penalized M-estimator for (partial) autocorrelation, with the penalty pushing the estimator toward a target selected from the data. This both encapsulates and differs from previous attempts at penalized estimation for autocorrelation, which shrink the estimator toward the target value of zero. …


Some Improved Markov Chain Convergence Rates, Fun Choi John Chan May 2022

Some Improved Markov Chain Convergence Rates, Fun Choi John Chan

All Dissertations

Explicit convergence rates to equilibrium are established for non reversible Markov chains not having an atom via coupling methods. We consider two Markov chains having the same transition function but different initial conditions on the same probability space, that is, a coupling. A random time is constructed so that subsequent to the random time the two processes are identical. Exploiting a shadowing condition, we show that it is possible to bound the tail distribution of the random time using only one of the chains. This bound gives the convergence rate to equilibrium for the Markov chain. The method is then …


Groundwork For The Development Of Gpu Enabled Group Testing Regression Models, Paul Cubre May 2022

Groundwork For The Development Of Gpu Enabled Group Testing Regression Models, Paul Cubre

All Dissertations

In this dissertation, we develop novel techniques that allow for the regression analysis of data emerging from group testing processes and set the groundwork for graphic processing units (GPU) enabled implementations. Group testing primarily occurs in clinical laboratories, where it is used to quickly and cheaply diagnose patients. Typically, group testing tests a pooled specimen--several specimens combined into one sample--instead of testing individual specimens one-by-one. This method reduces costs by using fewer tests when the disease prevalence is low. Due to recent advances in diagnostic technology, group testing protocols were extended to incorporate multiplex assays, which are diagnostic tests that, …


Extractive Membranes For The Detection And Screening Of Waterborne Plutonium, James Foster May 2022

Extractive Membranes For The Detection And Screening Of Waterborne Plutonium, James Foster

All Dissertations

The development of rapid screening tools for special nuclear materials remains a crucial focus for nonproliferation efforts. Traditional approaches for the analysis of trace-level Pu isotopes in water requires tedious and time-consuming sample preparation steps that do not lend well to expeditious screening. Therefore, a novel analytical method that combines both Pu concentration and source preparation into a single detection system would make for an invaluable tool for nuclear security applications. Extractive membranes absorbers can help to fulfill this role as they are capable of concentrating Pu to detectable limits while subsequently serving as alpha spectrometry sample sources. In Chapter …


Automated Parallel Optimization Of Simulation Parameters Using Modified Nelder-Mead Simplex Algorithm, Erina Mills May 2022

Automated Parallel Optimization Of Simulation Parameters Using Modified Nelder-Mead Simplex Algorithm, Erina Mills

All Dissertations

Computational simulations used in many fields have parameters that define models that are used to evaluate simulated properties. When developing these models, the goal is to choose the parameters that best replicate a set of desired properties. Mathematical optimization methods can be used to optimize the simulation parameters by defining a function that uses simulation parameters as input and outputs a value describing how well a set of experimental properties are reproduced.

Because simulated properties are often calculated using stochastic sampling methods, this optimization involves an objective function that is noisy and expensive to evaluate. Also, optimization of the simulation …


Cell Tracking At Low Frame Rate Using Deep Learning And Bayesian Integration, Xiang Zhang May 2022

Cell Tracking At Low Frame Rate Using Deep Learning And Bayesian Integration, Xiang Zhang

All Dissertations

Tracking cells over time is a fundamental task in live-cell imaging, and often requires costly manual analysis if images are not acquired with high enough frame rate. Acquiring high frame rate images, however, can limit the number of conditions explored and cells analyzed, and contribute to photobleaching, which makes fluorophores dimmer and phototoxicity, which affects cell health and renders the resulting data unusable.

Assuming a relatively high frame rate in image acquisition, state-of-the-art cell tracking approaches rely on either spatial proximity or morphological similarity to link cells in consecutive frames. The problem is that, at low frame rate, both approaches …


Establishing Pteridine Metabolism In A Progressive Isogenic Breast Cancer Cell Model – Part Ii, Lindsey Rasmussen, Zachary Foulks, Jiandong Wu, Casey Burton, Honglan Shi May 2022

Establishing Pteridine Metabolism In A Progressive Isogenic Breast Cancer Cell Model – Part Ii, Lindsey Rasmussen, Zachary Foulks, Jiandong Wu, Casey Burton, Honglan Shi

Chemistry Faculty Research & Creative Works

Introduction: Determining the biological significance of pteridines in cancer development and progression remains an important step in understanding the altered levels of urinary pteridines seen in certain cancers. Our companion study revealed that several folate-derived pteridines and lumazines correlated with tumorigenicity in an isogenic, progressive breast cancer cell model, providing direct evidence for the tumorigenic origin of pteridines. Objectives: This study sought to elucidate the pteridine biosynthetic pathway in a progressive breast cancer model via direct pteridine dosing to determine how pteridine metabolism changes with tumorigenicity. Methods: First, MCF10AT breast cancer cells were dosed individually with 15 pteridines to determine …


Parallel Construction Of Random Forest On Gpu, Kennedy Senagi, Nicolas Jouandeau May 2022

Parallel Construction Of Random Forest On Gpu, Kennedy Senagi, Nicolas Jouandeau

All Peer-Reviewed Publications

There is tremendous growth of data generated from different industries, i.e., health, agriculture, engineering, etc. Consequently, there is demand for more processing power. Compared to computer processing units, general-purpose graphics processing units (GPUs) are rapidly emerging as a promising solution to achieving high performance and energy efficiency in various computing domains. Multiple forms of parallelism and complexity in memory access have posed a challenge in developing Random Forest (RF) GPU-based algorithm. RF is a popular and robust machine learning algorithm. In this paper, coarse-grained and dynamic parallelism approaches on GPU are integrated into RF(dpRFGPU). Experiment results of dpRFGPU are compared …


Yang-Mills Sources In Biconformal Double Field Theory, Davis W. Muhwezi May 2022

Yang-Mills Sources In Biconformal Double Field Theory, Davis W. Muhwezi

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

There is a robust and unifying approach to unraveling the roiling mysteries of the universe. Our most compelling accounts of physical reality at present rest on symmetry arguments that are conspicuously geometrical!

105 years ago, Albert Einstein derived gravity from Riemannian geometry. In the general theory of relativity, the world of our experience is a pseudo-Riemannian manifold whose curvature represents the gravitational field. Encoded in the Einstein field equation is how matter sources (energy-momentum tensor) couple to gravity (spacetime curvature). Schematically, the Einstein equation exhibits a more general structure:

Curvature of Spacetime = Material Sources

On one side of the …


High Spatial And Temporal Resolution Census Data Reveals Communities At Risk Along The Wildland-Urban Interface (Wui) In California, Usa, Jessica E. Viner, Slade T. Laszewski, Wesley Ho, Justin Ewoldt, Pionnah Gregorio, Liz Lyon, Brian Hoover, Shenyue Jia May 2022

High Spatial And Temporal Resolution Census Data Reveals Communities At Risk Along The Wildland-Urban Interface (Wui) In California, Usa, Jessica E. Viner, Slade T. Laszewski, Wesley Ho, Justin Ewoldt, Pionnah Gregorio, Liz Lyon, Brian Hoover, Shenyue Jia

Mathematics, Physics, and Computer Science Faculty Articles and Research

We tracked census tract level population change along California's wild land-urban interface (WUI) during the past decade (2010-2019), an ecological sensitive region transitioning from developed land to wilderness. Our results from Mann-Kendall analysis, a method employed for monotonic trend detection showed that about one-third (29.1%) of census tracts in California’s WUI have seen a significant population increase from 2010 to 2019, affecting 12.7% population in California.

The population increase along WUI is largely driven by the sixteen counties in the San Francisco Bay Area (10) and Southern California (6). We also found that higher proportion of WUI residents in Bay …


Engaging Undergraduate Students In An Introductory A.I. Course Through A Knowledge-Based Chatbot Workshop, Thomas Menkhoff, Ying Teo Lydia Qian May 2022

Engaging Undergraduate Students In An Introductory A.I. Course Through A Knowledge-Based Chatbot Workshop, Thomas Menkhoff, Ying Teo Lydia Qian

Research Collection Lee Kong Chian School Of Business

In this paper we share interim results of an ongoing mixed method evaluative study of 43 students enrolled in an elective course “Doing Business with A.I.” at the Lee Kong Chian School of Business (LKCSB), Singapore Management University. A key component of the course design is an experiential chatbot workshop that provides non-STEM students with an opportunity to acquire basic skills to build a chatbot prototype using the ‘Dialogflow’ program. The workshop and the experiential learning activity were designed to impart students with relevant knowledge and skills such as conversation and user-centric design know how and know why that are …


Computational Approaches To Facilitate Automated Interchange Between Music And Art, Rao Hamza Ali May 2022

Computational Approaches To Facilitate Automated Interchange Between Music And Art, Rao Hamza Ali

Computational and Data Sciences (PhD) Dissertations

Recently, there has been a tremendous increase in generating and synthesizing music and art using various computational techniques. An area that is still under-researched, however, is how one medium can be converted into the other, while maintaining the overall aesthetics. Over the last few centuries, artists, composers, and scholars, have attempted to use substitute one form of art for the other: by proposing techniques where music notes are synonymous to colors, by inventing instruments that combine the aesthetics of music and visual art, and by incorporating the two media in live performances. A widely accepted computational approach, for the conversion, …


Combining Pharmacokinetics And Vibrational Spectroscopy: Mcr-Als Hard-And-Soft Modelling Of Drug Uptake In Vitro Using Tailored Kinetic Constraints, David Perez-Guaita, Guillermo Quintas, Zeineb Farhane, Roma Tauler, Hugh Byrne May 2022

Combining Pharmacokinetics And Vibrational Spectroscopy: Mcr-Als Hard-And-Soft Modelling Of Drug Uptake In Vitro Using Tailored Kinetic Constraints, David Perez-Guaita, Guillermo Quintas, Zeineb Farhane, Roma Tauler, Hugh Byrne

Articles

Raman microspectroscopy is a label-free technique which is very suited for the investigation of pharmacokinetics of cellular uptake, mechanisms of interaction, and efficacies of drugs in vitro. However, the complexity of the spectra makes the identification of spectral patterns associated with the drug and subsequent cellular responses difficult. Indeed, multivariate methods that relate spectral features to the inoculation time do not normally take into account the kinetics involved, and important theoretical information which could assist in the elucidation of the relevant spectral signatures is excluded. Here, we propose the integration of kinetic equations in the modelling of drug uptake and …


Exploring Methods To Persuade Users To Watch Social Problem Films Through The Case Study Of Race-Related Films, Clay Troyer '22 May 2022

Exploring Methods To Persuade Users To Watch Social Problem Films Through The Case Study Of Race-Related Films, Clay Troyer '22

Honor Scholar Theses

The present study reports on the success of persuasive techniques and recommendation engine on persuading participants to choose a race-related movie. The study used a technical component as well as an experimental study to see how users respond to certain persuasive techniques. The technical component included a content-based filtering recommendation engine to recommend lists of movies to participants based on films they already enjoy. Persuasive techniques were then applied to those lists and results were measured and analyzed. This project aims to explore the relationship that recommendation engines and persuasive techniques have on users and their willingness to branch out …


I'M Special But A.I. Doesn't Get It, Huei Huei Laurel Teo May 2022

I'M Special But A.I. Doesn't Get It, Huei Huei Laurel Teo

Dissertations and Theses Collection (Open Access)

A growing body of management research on artificial intelligence (AI) has consistently shown that people innately distrust decisions made by AI and find such decision processes simply less fair compared to decisions made by humans. My dissertation adopts a different perspective to propose that aside from fairness concerns, AI decision methods trigger perceptions in people that their individual uniqueness has not be adequately considered and this has negative consequences for their psychological or subjective well-being.

By combining theories of uniqueness, individuality, power, and well-being, I develop five studies to provide empirical evidence that aversion to AI-mediated decisions also operates through …


Objective Crystallographic Symmetry Classifications Of A Noisy Crystal Pattern With Strong Fedorov-Type Pseudo­Symmetries And Its Optimal Image-Quality Enhancement, Peter Moeck May 2022

Objective Crystallographic Symmetry Classifications Of A Noisy Crystal Pattern With Strong Fedorov-Type Pseudo­Symmetries And Its Optimal Image-Quality Enhancement, Peter Moeck

Physics Faculty Publications and Presentations

Statistically sound crystallographic symmetry classifications are obtained with information-theory-based methods in the presence of approximately Gaussian distributed noise. A set of three synthetic patterns with strong Fedorov-type pseudo­symmetries and varying amounts of noise serve as examples. Contrary to traditional crystallographic symmetry classifications with an image processing program such as CRISP, the classification process does not need to be supervised by a human being and is free of any subjectively set thresholds in the geometric model selection process. This enables crystallographic symmetry classification of digital images that are more or less periodic in two dimensions (2D), also known as crystal …