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Articles 271 - 300 of 2906

Full-Text Articles in Physical Sciences and Mathematics

Field Investigations And Numerical Modeling Of Earthquake And Tsunami Risk At Four Vulnerable Sites In Indonesia, Claire E. Ashcraft Dec 2021

Field Investigations And Numerical Modeling Of Earthquake And Tsunami Risk At Four Vulnerable Sites In Indonesia, Claire E. Ashcraft

Theses and Dissertations

Maps and models of seismic and tsunami risk are constructed from a variety of measurements taken in Indonesia, which have the potential to reduce loss of life and infrastructure. The first study uses the multichannel analysis of surface waves (MASW) method to calculate the time-averaged shear wave velocity to 30 m depth (Vs30). These measurements were taken at 58 sites in the city of Pacitan, Java and on the islands of Lombok, Ambon, and the Banda Islands. Vs30 calculations are compared with local geologic maps to extrapolate site class for locations not measured directly. Site class maps are then compared …


Galectin-1: Development Of A Novel Protein Therapy For Lgmd2b, Mary Lorena Vallecillo Munguia Dec 2021

Galectin-1: Development Of A Novel Protein Therapy For Lgmd2b, Mary Lorena Vallecillo Munguia

Theses and Dissertations

Muscular dystrophies are a heterogeneous group of genetic diseases that involve mutations in genes leading to progressive muscular weakness. Limb-Girdle Muscular Dystrophy 2B (LGMD2B) is a subset of muscular dystrophy caused by mutations in the DYSF gene, which encodes for dysferlin protein and has an incidence of 1/100,000-1/200,000 people, or 1/300 people of Libyan Jewish descent. Since there is no effective treatment that can cure or reverse effects of LGMD2B once diagnosed, our goal is to investigate and develop a protein therapy that mitigates effects of this disease in patients. Galectin-1 (Gal-1) is a small, soluble 14.5 kDa protein with …


Non-Linear Optical Characterization Of Stressed Materials, Kaylee N. Rellaford Dec 2021

Non-Linear Optical Characterization Of Stressed Materials, Kaylee N. Rellaford

Theses and Dissertations

Interactions between materials, their surfaces, and applied stresses are involved in every man-made construction in the world. Therefore, finding ways to interact without altering inherent properties of materials is of great interest. Surface spectroscopies, including second harmonic generation (SHG) and sum frequency generation (SFG), are inherently noninvasive testing methods. Both SHG and SFG are well-developed techniques that can be used in various applications including the characterization of material state. Both of these techniques allow for a noninvasive analysis of various materials, such as metals and polymers. We have used SHG as a method to characterize the change in signal strength …


Totally P-Adic Numbers Of Degree 4, Melissa Janet Ault Dec 2021

Totally P-Adic Numbers Of Degree 4, Melissa Janet Ault

Theses and Dissertations

In this thesis, we extend results of Emerald Stacy to compute an upper bound on the minimal height of a totally p-adic algebraic integer of degree 4 independent of p. We also compute actual values of the minimal height of a totally p-adic algebraic integer of degree 4 for small primes p.


Zeros Of A Two-Parameter Family Of Harmonic Trinomials, David Work Dec 2021

Zeros Of A Two-Parameter Family Of Harmonic Trinomials, David Work

Theses and Dissertations

This thesis studies complex harmonic polynomials of the form $f(z) = az^n + b\bar{z}^k+z$ where $n, k \in \mathbb{Z}$ with $n > k$ and $a, b > 0$. We show that the sum of the orders of the zeros of such functions is $n$ and investigate the locations of the zeros, including whether the zeros are in the sense-preserving or sense-reversing region and a set of conditions under which zeros have the same modulus. We also show that the number of zeros ranges from $n$ to $n+2k+2$ as long as certain criteria are met.


Computing Agent Competency In First Order Markov Processes, Xuan Cao Dec 2021

Computing Agent Competency In First Order Markov Processes, Xuan Cao

Theses and Dissertations

Artificial agents are usually designed to achieve specific goals. An agent's competency can be defined as its ability to accomplish its goals under different conditions. This thesis restricts attention to a specific type of goal, namely reaching a desired state without exceeding a tolerance threshold of undesirable events in a first-order Markov process. For such goals, the state-dependent competency for an agent can be defined as the probability of reaching the desired state without exceeding the threshold and within a time limit given an initial state. The thesis further defines total competency as the set of state-dependent competency relationships over …


Weak Cayley Table Groups Of Crystallographic Groups, Rebeca Ann Paulsen Dec 2021

Weak Cayley Table Groups Of Crystallographic Groups, Rebeca Ann Paulsen

Theses and Dissertations

Let G be a group. A weak Cayley table isomorphism $\phi$: G $\rightarrow$ G is a bijection satisfying two conditions: (i) $phi$ sends conjugacy classes to conjugacy classes; and (ii) $\phi$(g1)$\phi$(g2) is conjugate to $\phi$(g1g2) for all g1, g2 in G. The set of all such mappings forms a group W(G) under composition. We study W(G) for fifty-six of the two hundred nineteen three-dimensional crystallographic groups G as well as some other groups. These fifty-six groups are related to our previous work on wallpaper groups.


Fabrication Of Advanced Materials For Chromatography, Sample Preparation, And Separations, And Accompanying Material Characterization, Dhananjay I. Patel Dec 2021

Fabrication Of Advanced Materials For Chromatography, Sample Preparation, And Separations, And Accompanying Material Characterization, Dhananjay I. Patel

Theses and Dissertations

My dissertation primarily focuses on the fabrication of materials for solid phase microextraction (SPME) and separation devices. In my first project, I used direct current magnetron sputtering (DCMS) to prepare sputtered silicon coatings on fused silica fibers. These fibers were then subjected to the chemical vapor deposition of 6-phenyhexylsilane (6-PH) as a stationary phase. Six different types of fibers were made using two different throw distances (4 cm and 20 cm) and three different silicon thicknesses (0.5, 1.8, and 2.8 µm). These coatings were characterized by time-of-flight secondary ion mass spectrometry (ToF-SIMS), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), …


Chemical And Physical Weathering Rates Of Basaltic Volcanic Regions: Utilizing Space In Place Of Time In The Hawaiian Archipelago, Benjamin Clyde Barton Dec 2021

Chemical And Physical Weathering Rates Of Basaltic Volcanic Regions: Utilizing Space In Place Of Time In The Hawaiian Archipelago, Benjamin Clyde Barton

Theses and Dissertations

With large populations living in tropical regions of the world with volcanic substrates, understanding basalt weathering processes is vital. The Hawaiian Islands are an excellent natural analogue to study chemical weathering rates due to a uniform bedrock (basalt), large variations in rainfall, and varying ages across the islands. Laterite weathering profiles (LWP) develop over time through chemical weathering, where LWP thickness is influenced by many factors, including precipitation and time. Using the rapid, non-invasive horizontal-to-vertical spectral ratio (HVSR) method, LWP thicknesses can be estimated to constrain chemical weathering rates. Studying the laterite weathering profiles developed from basaltic bedrock of varying …


Order And Harmony: Kepler’S Guiding Forces, Dan Broadbent Dec 2021

Order And Harmony: Kepler’S Guiding Forces, Dan Broadbent

Faculty Publications

Adapted from the article “Order and Harmony: Kepler’s Guiding Forces” included in “Towards Mysteries of the Cosmos with Johannes Kepler – on the 450th Anniversary of His Birth,” a commemorative volume published by the Obserwatorium Atronommiczne Krolowej Jadwigi Rzepienniku Biskupim (Queen Jadwiga Observatory of Rzepiennik Biskupi Poland) December 2021. Adapted with permission.

As the subject librarian for physics and astronomy at Brigham Young University, the author has had the privilege of handling some of Johannes Kepler’s original books preserved in the university’s archives. One of the most impressive materials in the archive is a large page from Mysterium Cosmographicum that …


Exploring Improvements To The Convergence Of Reconstructing Historical Destructive Earthquakes, Kameron Lightheart Nov 2021

Exploring Improvements To The Convergence Of Reconstructing Historical Destructive Earthquakes, Kameron Lightheart

Theses and Dissertations

Determining risk to human populations due to natural disasters has been a topic of interest in the STEM fields for centuries. Earthquakes and the tsunamis they cause are of particular interest due to their repetition cycles. These cycles can last hundreds of years but we have only had modern measuring instruments for the last century or so which makes analysis difficult. In this document, we explore ways to improve upon an existing method for reconstructing earthquakes from historical accounts of tsunamis. This method was designed and implemented by Jared P Whitehead's research group over the last 5 years. The issue …


Modeling User Relationships In Online Communities Of Creators, Berkeley Andrus Nov 2021

Modeling User Relationships In Online Communities Of Creators, Berkeley Andrus

Theses and Dissertations

Those who study creativity, especially from a computational perspective, have long understood the role of social influence in the creative process. This has motivated many efforts to simulate social mechanics in artificial creative systems. However, these simulations have often replicated generic or assumed human behaviors rather than specific anthropological data. In this work we take a more focused approach by quantitatively measuring interactions between creators in online social communities and replicating observed phenomena in a simulated environment. The primary contributions of this thesis are 1) defining quantitative metrics for comparing human and simulated social networks of creators, 2) providing social …


Determining The Anthropogenic Effects On Eutrophication Of Utah Lake Since European Settlement Using Multiple Geochemical Approaches, Richard Ronald Rawle Williams Oct 2021

Determining The Anthropogenic Effects On Eutrophication Of Utah Lake Since European Settlement Using Multiple Geochemical Approaches, Richard Ronald Rawle Williams

Theses and Dissertations

Recent urbanization of Utah Valley, Utah, has highlighted the impacts of anthropogenically-driven eutrophication of Utah Lake, which may lead to more frequent harmful algal blooms. To examine changes in trophic state, three freeze cores were taken from Utah Lake (Goshen Bay, Provo Bay, and near the Provo Boat Harbor) to examine the extent of eutrophication since European settlement. 210Pb and 137Cs chronologies were constructed for all three cores, although due to low supported 210Pb in the Provo Boat Harbor core, an additional pollen analysis was performed. Lower juniper pollen counts in addition to higher POACEAE (grasses and cereals) counts above …


Beware Of Ips In Sheep's Clothing: Measurement And Disclosure Of Ip Spoofing Vulnerabilities, Alden Douglas Hilton Oct 2021

Beware Of Ips In Sheep's Clothing: Measurement And Disclosure Of Ip Spoofing Vulnerabilities, Alden Douglas Hilton

Theses and Dissertations

Networks not employing destination-side source address validation (DSAV) expose themselves to a class of pernicious attacks which could be prevented by filtering inbound traffic purporting to originate from within the network. In this work, we survey the pervasiveness of networks vulnerable to infiltration using spoofed addresses internal to the network. We issue recursive Domain Name System (DNS) queries to a large set of known DNS servers world-wide using various spoofed-source addresses. In late 2019, we found that 49% of the autonomous systems we tested lacked DSAV. After a large-scale notification campaign run in late 2020, we repeated our measurements in …


Reducing The Manual Annotation Effort For Handwriting Recognition Using Active Transfer Learning, Eric Burdett Aug 2021

Reducing The Manual Annotation Effort For Handwriting Recognition Using Active Transfer Learning, Eric Burdett

Theses and Dissertations

Handwriting recognition systems have achieved remarkable performance over the past several years with the advent of deep neural networks. For high-quality recognition, these models require large amounts of labeled training data, which can be difficult to obtain. Various methods to reduce this effort have been proposed in the realms of active and transfer learning, but not in combination. We propose a framework for fitting new handwriting recognition models that joins active and transfer learning into a unified framework. Empirical results show the superiority of our method compared to traditional active learning, transfer learning, or standard supervised training schemes.


Encirclement Of Moving Targets Using Noisy Range And Bearing Measurements, Cammy Peterson, Puneet Jain, Randal Beard Aug 2021

Encirclement Of Moving Targets Using Noisy Range And Bearing Measurements, Cammy Peterson, Puneet Jain, Randal Beard

Faculty Publications

This paper presents theoretically justified controllers that use relative range and bearing measurements to steer a team of autonomous vehicles, operating without inertial position information, to circular trajectories around a constant-acceleration, constant-velocity, or stationary target. An extended Kalman filter is used to improve the noisy relative measurements and estimate the velocity of the moving target. These estimated values are used in the control laws to encircle constant-velocity moving targets. Lyapunov techniques are utilized to show that the vehicle will converge to the desired circular formations. Additionally, cooperating vehicles are shown to converge to a circular formation with equal temporal spacing …


Sd1 14-3-3 Interactome For Ptov1 Manuscript, Joshua Andersen Aug 2021

Sd1 14-3-3 Interactome For Ptov1 Manuscript, Joshua Andersen

ScholarsArchive Data

Excel data sheet of MS data from 14-3-3 interactomics


Sd2 Ptov1 Interactomics, Joshua Andersen Aug 2021

Sd2 Ptov1 Interactomics, Joshua Andersen

ScholarsArchive Data

PTOV1 interactome data


Sd3 Ptov1 Ptms, Joshua Andersen Aug 2021

Sd3 Ptov1 Ptms, Joshua Andersen

ScholarsArchive Data

MS data on PTOV1 PTMs


Sd1 14-3-3 Interactome For Ptov1 Manuscript, Joshua Andersen Aug 2021

Sd1 14-3-3 Interactome For Ptov1 Manuscript, Joshua Andersen

ScholarsArchive Data

14-3-3 interactome


Turn Of Phrase: Contrastive Pre-Training For Discourse-Aware Conversation Models, Roland Laboulaye Aug 2021

Turn Of Phrase: Contrastive Pre-Training For Discourse-Aware Conversation Models, Roland Laboulaye

Theses and Dissertations

Understanding long conversations requires recognizing a discourse flow unique to conversation. Recent advances in unsupervised representation learning of text have been attained primarily through language modeling, which models discourse only implicitly and within a small window. These representations are in turn evaluated chiefly on sentence pair or paragraph-question pair benchmarks, which measure only local discourse coherence. In order to improve performance on discourse-reliant, long conversation tasks, we propose Turn-of-Phrase pre-training, an objective designed to encode long conversation discourse flow. We leverage tree-structured Reddit conversations in English to, relative to a chosen conversation path through the tree, select paths of varying …


Exploring Non-Functional Coupling Between Subsystems, Matt Pope Aug 2021

Exploring Non-Functional Coupling Between Subsystems, Matt Pope

Theses and Dissertations

Many software systems depend on other systems to function correctly or are themselves composed of interdependent subsystems. In that context, behavioral changes in a dependency may have consequences for a dependent subsystem. This includes changes to non-functional properties such as latency or availability. In this paper we use the term non-functional coupling to mean the extent to which a subsystem is affected by changes to non-functional properties in a dependency. We argue that non-functional coupling has implications for the maintainability, reliability and performance of an overall system. We also explore the extent to which various engineering techniques used in interaction …


Predicting Human Behavior In Repeated Games With Attitude Vectors, Brian L. James Aug 2021

Predicting Human Behavior In Repeated Games With Attitude Vectors, Brian L. James

Theses and Dissertations

As Artificial Intelligence systems are used by human users at an increasing frequency, the need for such systems to understand and predict human behavior likewise increases. In my work, I have considered how to predict human behavior in repeated games. These repeated games can be applied as a foundation to many situations where a person may interact with an AI, In an attempt to create such a foundation, I have built a system using Attitude Vectors used in automata to predict actions based on prior actions and communications. These Attitude Vector Automata (AVA) can transform information from actions in one …


Decision Based Learning Course Design & Implementation For Introductory Statistics, Austin Heath Aug 2021

Decision Based Learning Course Design & Implementation For Introductory Statistics, Austin Heath

Undergraduate Honors Theses

Researchers in multiple industries (biomedicine, engineering, etc.) cite the selection of an appropriate statistical test as a common problem. Experts draw on a framework of conceptual and procedural knowledge to navigate when to use statistical methods. Students also struggle determining the correct statistical method to use for a given research question. This is because they lack the opportunity to practice recognizing a host of features in each research question that provide clues for experts as to which method is most appropriate. “Decision Based Learning” (DBL) is a teaching method designed to help teachers and students address this struggle. In this …


A Usability Study Of Fido2 Roaming Software Tokens As A Password Replacement, Brian Rasmussen Aug 2021

A Usability Study Of Fido2 Roaming Software Tokens As A Password Replacement, Brian Rasmussen

Theses and Dissertations

The use of passwords for user authentication has significant shortcomings. As society becomes more dependent on the internet and web services, we need to find a replacement authentication method that users are willing to use. WebAuthn is one potential technology for password replacement. Recent studies have shown that users enjoy the usability of WebAuthn and hardware tokens as a password replacement but don't want to carry them around. Meanwhile, little to no research involves the use of software tokens. I carried out a user study of WebAuthn and roaming software tokens when used as a password replacement. We were able …


Molecular Dynamics Of Organometallic Systems, Ryan Wayne Carlsen Aug 2021

Molecular Dynamics Of Organometallic Systems, Ryan Wayne Carlsen

Theses and Dissertations

Metal-mediated organometallic reactions are critical for both catalytic and synthetic chemistry. Density functional theory (DFT) potential-energy calculations are routinely used with a transition-state theory type of approach to understand and predict the reaction mechanisms of organometallic reactions. However, these calculations do not include atomic momentum and thus ignore dynamic effects. Molecular dynamics is a powerful tool for elucidating mechanistic details of chemical reactions. In this dissertation, quasiclassical molecular dynamics studies reveal key mechanistic details about several fundamental organometallic reactions. Chapter 1 provides a brief overview of key molecular dynamics details. Chapters 2-4 provide details on for three classic organometallic reactions …


Immunoaffinity Monoliths For Multiplexed Extraction Of Preterm Birth Biomarkers From Human Blood Serum In 3d Printed Microfluidic Devices, Haifa Mohammad Almughamsi Aug 2021

Immunoaffinity Monoliths For Multiplexed Extraction Of Preterm Birth Biomarkers From Human Blood Serum In 3d Printed Microfluidic Devices, Haifa Mohammad Almughamsi

Theses and Dissertations

Preterm birth (PTB) results in over 15 million early births annually and is the leading cause of neonatal deaths. There are no clinical methods currently available to evaluate risk of PTB at early stages in pregnancy; thus, a rapid diagnostic to analyze PTB risk would be beneficial. Microfluidic immunoaffinity extraction is a promising platform for preparing complex samples, such as maternal serum with PTB risk biomarkers. 3D printed microfluidic devices have advantages over conventional microfluidic systems including simple fabrication and potential for iterative optimization to improve designs. In this work, I developed immunoaffinity monoliths in 3D printed microfluidic devices modified …


Petal Diagrams And Seifert Surfaces, Jason Robert Gardiner Aug 2021

Petal Diagrams And Seifert Surfaces, Jason Robert Gardiner

Theses and Dissertations

Petal diagrams of knots are projections of knots to the plane such that the diagram has exactly one crossing. Petal diagrams offer a convenient and combinatorial way of representing knots via their associated petal permutation. In this thesis we study the fundamental group and Seifert surfaces of knots in petal form. Using the Seifert-Van Kampen theorem, we give a group presentation of the fundamental group of the knot complement of a knot in petal form. We then discuss Seifert surfaces and use decomposition diagrams to represent the Seifert surfaces of knots in petal form. We finally give an algorithm to …


Synthesis And Biological Evaluation Of Pyrazolo[1,5-A]Pyrimidines And (4-Hydroxy-6-Trifluoromethylpyrimidin-2-Yl) Guanidines, Justin Dave Singleton Aug 2021

Synthesis And Biological Evaluation Of Pyrazolo[1,5-A]Pyrimidines And (4-Hydroxy-6-Trifluoromethylpyrimidin-2-Yl) Guanidines, Justin Dave Singleton

Theses and Dissertations

A microwave reactor was used to synthesize a series of novel 3,6-disubstituted or 3-substituted pyrazolo[1,5-a]pyrimidines in a total of 1 hour reaction time over 3 steps. The products were obtained in good to excellent yields (34-92%, ave = 52%) using a straightforward synthesis starting with the reaction of dimethylformamide-dimethylacetal with commercially available aryl acetonitriles (120C, 20 min). This was followed by treatment with H2NNH2 • HBr (120C, 20 min), and then reacted with either 1,1,3,3-tetramethoxypropane or a 2-aryl-substituted malondialdehydes (120C, 20 min). The resulting product was either collected on a sintered glass funnel or purified via column chromatography. The compounds …


Invariant Lattices Of Several Elliptic K3 Surfaces, Joshua Joseph Fullwood Jul 2021

Invariant Lattices Of Several Elliptic K3 Surfaces, Joshua Joseph Fullwood

Theses and Dissertations

This work is concerned with computing the invariant lattices of purely non-symplectic automorphisms of special elliptic K3 surfaces. Brandhorst gave a collection of K3 surfaces admitting purely non-symplectic automorphisms that are uniquely determined up to isomorphism by certain invariants. For many of these surfaces, the automorphism is also unique or the automorphism group of the surface is finite and with a nice isomorphism class. Understanding the invariant lattices of these automorphisms and surfaces is interesting because of these uniqueness properties and because it is possible to give explicit generators for the Picard and invariant lattices. We use the methods given …