Physical Sciences and Mathematics Commons^™

Stubbornly Merging Discrete Vector Fields, Douglas W. Lenseth

Legacy Theses & Dissertations (2009 - 2024)

We address the basic question in discrete Morse theory of combining discrete gradientfields that are partially defined on subsets of the given complex. This is a well-posed question when the discrete gradient field V is generated using a fixed algorithm which has a local nature. One example is ProcessLowerStars, a widely used algorithm for computing persistent homology associated to a grayscale image in 2D or 3D. While the algorithm for V may be inherently local, being computed within stars of vertices and so embarrassingly parallelizable, in practical use it is natural to want to distribute the computation over patches Pi, …

An Entropic Approach To Dynamics, Pedro Henrique Moreira Pessoa

Legacy Theses & Dissertations (2009 - 2024)

The present thesis deals with different aspects of probability, the method of maximum entropy, information geometry, and dynamical systems and their applications to statistical physics and complex systems. Those topics come together in the framework for dynamics termed entropic dynamics. Work on the topic was initiated by my PhD advisor Professor Ariel Caticha and many colleagues at University at Albany as a method for explaining the dynamical processes in quantum mechanics from first principles of probability theory.

Signal Yields And Detector Modeling In Xenon Time Projection Chambers, And Results Of An Effective Field Theory Dark Matter Search Using Lux Data, Gregory Ransford Carl Rischbieter

Legacy Theses & Dissertations (2009 - 2024)

The nature of dark matter continues to be one of the biggest remaining mysteries in physics. Astrophysical measurements indicate that dark matter makes up more than a quarter of the Universe's total energy density, and it is well-motivated that dark matter is comprised of Weakly Interacting Massive Particles (WIMPs). Direct detection techniques utilizing liquid and gaseous noble elements have become the primary method of probing the potential non-gravitational interactions between WIMPs and Standard Model matter, with the leading technology being the dual-phase Time Projection Chamber (TPC). The Large Underground Xenon (LUX) and its second-generation successor, LUX-ZEPLIN (LZ), are two xenon …

Gas-Phase Proton Affinities For Twenty Of The Proline-Containing Dipeptides, Henry Cardwell

Undergraduate Honors Theses

Peptide fragmentation plays a crucial role in the analysis of proteins through mass spectrometry-based proteomics. Most proteomics experiments take place in the low-energy regime and are governed by the mobile proton model which predicts random cleavages along the peptide backbone; however, there sometimes arise circumstances where the mobile proton model fails causing sequencing algorithms to misidentify peptides. One such example is noted in the “proline effect” wherein proline-containing peptides preferentially fragment N-terminal. While it has been established that the “proline effect” is due to the rigidity and basicity of the proline N-terminus, a further understanding of the factors influencing the …

Co-Planar Waveguides For Microwave Atom Chips, Morgan Logsdon

Undergraduate Honors Theses

This thesis describes research to develop co-planar waveguides (CPW) for coupling microwaves from mm-scale coaxial cables into 50 μm-scale microstrip transmission lines of a microwave atom chip. This new atom chip confines and manipulates atoms using spin-specific microwave AC Zeeman potentials and is particularly well suited for trapped atom interferometry. The coaxial-to-microstrip coupler scheme uses a focused CPW (FCPW) that shrinks the microwave field mode while maintaining a constant 50 Ω impedance for optimal power coupling. The FCPW development includes the simulation, design, fabrication, and testing of multiple CPW and microstrip prototypes using aluminum nitride substrates. Notably, the FCPW approach …

Climate Change And Conservation Of Milkweed: Evidence Of Extensive Admixture Between Common Milkweed And Poke Milkweed, Elizabeth Davies

Undergraduate Honors Theses

Global climate change can drive many changes in species interactions. One primary way it affects species is by changing climates, causing species to expand their ranges and allowing them to interact with species from whom they were previously isolated. In plants, new species interactions can result in hybridization – the creation of hybrid offspring between two separate species. This hybridization can increase gene flow between the species and lead to introgression, the transfer of genetic material from one species to another through hybrid backcrossing with the parent species. My thesis investigates hybridization in the model system Asclepias (milkweed) by analyzing …

Chemical Analysis Of Organic Compounds In Dew Water, Monica Dibley

Undergraduate Honors Theses

Water films on outdoor surfaces, such as dew, can act as a reservoir for organic molecules deposited from the atmosphere and they present a potential reactive medium for chemical transformations. To better understand the flux of volatile organic compounds from evaporating films, the composition and reactivity of the complex mixture of dissolved organic material (DOM) found in these films need to be characterized. Previous studies have measured the salts and the small organic molecules in dew collected on clean Teflon surfaces or condensers. Here, we expand on this by probing the organic chemicals found on natural outdoor surfaces covered in …

Investigation Of Tertiary Impact Cratering And Relation To Impact Physics Theory, Mikayla Huffman

Undergraduate Honors Theses

Extraterrestrial impact crater formation is important in many subfields of planetary science, including geochronology, planetary formation, and dynamic fragmentation theory. Current dynamic fragmentation theory lacks scale dependence and relies heavily on terrestrial data. Exploring a range of impact and ejecta velocities as is produced by cratering events on the Moon may bridge the gap between heavily terrestrial-based theory and planetary data. The secondary craters of secondary craters deemed “tertiary craters,” have been theorized, but planetary images have not been of sufficient resolution to effectively search for them until recently. Tertiary craters are formed by relatively low-velocity fragments ejected by nearby …

Modern Theory Of Copositive Matrices, Yuqiao Li

Undergraduate Honors Theses

Copositivity is a generalization of positive semidefiniteness. It has applications in theoretical economics, operations research, and statistics. An $n$-by-$n$ real, symmetric matrix $A$ is copositive (CoP) if $x^T Ax \ge 0$ for any nonnegative vector $x \ge 0.$ The set of all CoP matrices forms a convex cone. A CoP matrix is ordinary if it can be written as the sum of a positive semidefinite (PSD) matrix and a symmetric nonnegative (sN) matrix. When $n < 5,$ all CoP matrices are ordinary. However, recognizing whether a given CoP matrix is ordinary and determining an ordinary decomposition (PSD + sN) is still an unsolved problem. Here, we give an overview on modern theory of CoP matrices, talk about our progress on the ordinary recognition and decomposition problem, and emphasis the graph theory aspect of ordinary CoP matrices.

Demonstration Of Cyberattacks And Mitigation Of Vulnerabilities In A Webserver Interface For A Cybersecure Power Router, Benjamin Allen

Computer Science and Computer Engineering Undergraduate Honors Theses

Cyberattacks are a threat to critical infrastructure, which must be secured against them to ensure continued operation. A defense-in-depth approach is necessary to secure all layers of a smart-grid system and contain the impact of any exploited vulnerabilities. In this undergraduate thesis a webserver interface for smart-grid devices communicating over Modbus TCP was developed and exposed to SQL Injection attacks and Cross-Site Scripting attacks. Analysis was performed on Supply-Chain attacks and a mitigation developed for attacks stemming from compromised Content Delivery Networks. All attempted attacks were unable to exploit vulnerabilities in the webserver due to its use of input sanitization …

Analysis Of Gpu Memory Vulnerabilities, Jarrett Hoover

Computer Science and Computer Engineering Undergraduate Honors Theses

Graphics processing units (GPUs) have become a widely used technology for various purposes. While their intended use is accelerating graphics rendering, their parallel computing capabilities have expanded their use into other areas. They are used in computer gaming, deep learning for artificial intelligence and mining cryptocurrencies. Their rise in popularity led to research involving several security aspects, including this paper’s focus, memory vulnerabilities. Research documented many vulnerabilities, including GPUs not implementing address space layout randomization, not zeroing out memory after deallocation, and not initializing newly allocated memory. These vulnerabilities can lead to a victim’s sensitive data being leaked to an …

A Study Of Software Development Methodologies, Kendra Risener

Computer Science and Computer Engineering Undergraduate Honors Theses

Software development methodologies are often overlooked by software engineers as aspects of development that are handled by project managers alone. However, if every member of the team better understood the development methodology being used, it increases the likelihood that the method is properly implemented and ultimately used to complete the project more efficiently. Thus, this paper seeks to explore six common methodologies: the Waterfall Model, the Spiral Model, Agile, Scrum, Kanban, and Extreme Programming. These are discussed in two main sections in the paper. In the first section, the frameworks are isolated and viewed by themselves. The histories, unique features, …

Using A Bert-Based Ensemble Network For Abusive Language Detection, Noah Ballinger

Computer Science and Computer Engineering Undergraduate Honors Theses

Over the past two decades, online discussion has skyrocketed in scope and scale. However, so has the amount of toxicity and offensive posts on social media and other discussion sites. Despite this rise in prevalence, the ability to automatically moderate online discussion platforms has seen minimal development. Recently, though, as the capabilities of artificial intelligence (AI) continue to improve, the potential of AI-based detection of harmful internet content has become a real possibility. In the past couple years, there has been a surge in performance on tasks in the field of natural language processing, mainly due to the development of …

The Effect Of Changing Land Use On Streamflow Statistics And Flood Flows Across Select Gages In Northwest Arkansas, Timothy Mcmullen

Civil Engineering Undergraduate Honors Theses

Since 1901, heavy rainfall events have increased in the United States in both intensity and frequency, and population in the United States has increased, resulting in significant land use changes. Both of these trends could explain an increase in observed flood magnitude and frequency. In order to determine if a relationship exists between land use/land cover and changing stream flows in northwest Arkansas, this study analyzed temporal changes in various flow statistics for fourteen stream gages and compared the rates of change in flow statistics from gages on streams with watersheds that have varying land uses, i.e. urban, agricultural, and …

Plastic Bottles In Architecture: A How To Guide On Life-Cycle Through Reuse, Crystallyne Landram

Architecture Undergraduate Honors Theses

This booklet is a collection of 6 case studies that utilize reused plastic bottles significantly within their design. Prior to working with the case studies, much time was dedicated to research that justified the need for such a project. In-depth research on the environmental crisis, waste management trends, stewardship, sustainability, and ethics was conducted and recorded in the introduction to contextualize the need for an accessible how-to guide such as this one. Time was also given to establishing background information on bottles, reprocessing, and architecture to elaborate further on each piece of the content matter. It is curated as a …

A Possible Alignment Between The Orbits Of Planetary Systems And Their Visual Binary Companions, S. Christian, A. Vanderburg, J. Becker, D. A. Yahalomi, L. Pearce, G. Zhou, K. A. Collins, A. L. Kraus, K. G. Stassun, Z. De Beurs, G. R. Ricker, R. K. Vanderspek, D. W. Latham, J. N. Winn, S. Seager, J. M. Jenkins, L. Abe, K. Agabi, P. J. Amado, D. Baker, K. Barkaoui, Z. Benkhaldoun, P. Benni, J. Berberian, P. Berlind, A. Bieryla, E. Esparza-Borges, M. Bowen, P. Brown, L. A. Buchhave, C. J. Burke, M. Buttu, C. Cadieux, D. A. Caldwell, D. Charbonneau, N. Chazov, S. Chimaladinne, K. I. Collins, D. Combs, D. M. Conti, N. Crouzet, J. P. De Leon, S. Deljookorani, B. Diamond, R. Doyon, D. Dragomir, G. Dransfield, Z. Essack, P. Evans, A. Fukui, T. Gan, G. A. Esquerdo, M. Gillon, E. Girardin, P. Guerra, T. Guillot, E. K. K. Habich, A. Henriksen, N. Hoch, K. I. Isogai, E. Jehin, Eric L.N. Jensen, M. C. Johnson, J. H. Livingston, J. F. Kielkopf, K. Kim, K. Kawauchi, V. Krushinsky, V. Kunzle, D. Laloum, D. Leger, P. Lewin, F. Mallia, B. Massey, M. Mori, K. K. Mcleod, D. Mékarnia, I. Mireles, N. Mishevskiy, M. Tamura, F. Murgas, N. Narita, R. Naves, P. Nelson, H. P. Osborn, E. Palle, H. Parviainen, P. Plavchan, F. J. Pozuelos, M. Rabus, H. M. Relles, C. Rodríguez López, S. N. Quinn, F.-X. Schmider, J. E. Schlieder, R. P. Schwarz, A. Shporer, L. Sibbald, G. Srdoc, C. Stibbards, H. Stickler, O. Suarez, C. Stockdale, T.-G. Tan, Y. Terada, A. Triaud, R. Tronsgaard, W. C. Waalkes, G. Wang, N. Watanabe, M.-S. Wenceslas, G. Wingham, J. Wittrock, C. Ziegler

Physics & Astronomy Faculty Works

Astronomers do not have a complete picture of the effects of wide-binary companions (semimajor axes greater than 100 au) on the formation and evolution of exoplanets. We investigate these effects using new data from Gaia Early Data Release 3 and the Transiting Exoplanet Survey Satellite mission to characterize wide-binary systems with transiting exoplanets. We identify a sample of 67 systems of transiting exoplanet candidates (with well-determined, edge-on orbital inclinations) that reside in wide visual binary systems. We derive limits on orbital parameters for the wide-binary systems and measure the minimum difference in orbital inclination between the binary and planet orbits. …

Thermal Expansion And Phonon Anharmonicity Of Cuprite Studied By Inelastic Neutron Scattering And Ab Initio Calculations, C. N. Saunders, D. S. Kim, O. Hellman, Hillary L. Smith, N. J. Weadock, S. T. Omelchenko, G. E. Ganroth, C. M. Bernal-Choban, S. H. Lohaus, D. L. Abernathy, B. Fultz

Physics & Astronomy Faculty Works

Inelastic neutron scattering measurements were performed with a time-of-flight chopper spectrometer to observe phonons in all parts of the Brillouin zone of a single crystal of cuprite Cu₂ O. We reduced the experimental data to phonon dispersions in the high-symmetry directions, and changes between 10 and 300 K are reported. In this paper, we show ab initio quasiharmonic (QH) and anharmonic (AH) calculations of phonon dispersions. We performed all AH calculations with a temperature-dependent effective potential method. Both QH and AH calculations account for the small negative thermal expansion of cuprite at low temperatures. However, the measured temperature-dependent phonon behavior …

State Estimation—Beyond Gaussian Filtering, Haozhan Meng

University of New Orleans Theses and Dissertations

This dissertation considers the state estimation problems with symmetric Gaussian/asymmetric skew-Gaussian assumption under linear/nonlinear systems. It consists of three parts. The first part proposes a new recursive finite-dimensional exact density filter based on the linear skew-Gaussian system. The second part adopts a skew-symmetric representation (SSR) of distribution for nonlinear skew-Gaussian estimation. The third part gives an optimized Gauss-Hermite quadrature (GHQ) rule for numerical integration with respect to Gaussian integrals and applies it to nonlinear Gaussian filters.

We first develop a linear system model driven by skew-Gaussian processes and present the exact filter for the posterior density with fixed dimensional recursive …

3-Uniform 4-Path Decompositions Of Complete 3-Uniform Hypergraphs, Rachel Mccann

Mathematical Sciences Undergraduate Honors Theses

The complete 3-uniform hypergraph of order v is denoted as K_v and consists of vertex set V with size v and edge set E, containing all 3-element subsets of V. We consider a 3-uniform hypergraph P₇, a path with vertex set {v₁, v₂, v₃, v₄, v₅, v₆, v₇} and edge set {{v₁, v₂, v₃}, {v₂, v₃, v₄}, {v₄, v₅, v₆}, {v₅, v_{6 …}

Social Science Research To Help Advance Regional Coordination And Collaboration Of Sea Level Rise Planning And Adaptation On Humboldt Bay, Kristen Orth-Gordinier

Student Projects

Humboldt Bay is experiencing the fastest rate of relative sea level rise in California and is likely to experience severe sea level rise (SLR) flooding within the next two decades. The Humboldt Bay shoreline is owned and governed by a patchwork of entities with different missions and jurisdictions so coordination of SLR planning will be critical because flooding of hydrologic areas from tidal waters can cross political boundaries. The goal of this project was to conduct social science research that can inform and advance the development of regional coordination and collaboration related to SLR in Humboldt Bay. To do this, …

Land And Water Resources For Irrigated Agriculture In The Pilbara, Paul Galloway, John A. Simons, Karen Holmes, Dennis Van Gool

Resource management technical reports

This report documents the procedures used to identify suitable locations for irrigation development in the Pilbara region. It is the first study to investigate the potential for irrigated agriculture across the Pilbara. We used a desktop analysis to ascertain water availability and spatial data modelling to determine the potential of the land and soil resource to support irrigated agriculture. This study was part of the Pilbara Hinterland Agricultural Development Initiative (PHADI).

We used existing rangeland land inventory information augmented with digital spatial environmental data, in a process known as map disaggregation, to create soil and landform maps that had a …

Built Environment, Land Use, And Crime: A Las Vegas Study, Stacey Lynn Clouse

UNLV Theses, Dissertations, Professional Papers, and Capstones

This study examined land use and crime against persons and crime against property in Las Vegas, Nevada at varying spatial levels of analysis. Using crime data provided by the Las Vegas Metropolitan Police Department and the Clark County Assessor’s office, results at the macro-level of analysis reveal that property crime rates concentrated on commercial, transportation, communication and utilities, and industrial land use, whereas violent crime concentrated at commercial, multi-residential, and civic, institutional, and recreational land use. Upon examining the subtypes of land use that generate or radiate more crime, property crime concentrated on transportation land use, class 1 resorts, and …

Modeling Functions Into An Angular Displacement Of An Elastic Pendulum, Brenda Lee Garcia

Theses and Dissertations

In this thesis we study the relation between analytic signals and a variety of pendulum systems. The representation of a signal as a pair of time varying amplitude and phase has been well studied and often related to linear mass spring systems. The differential equations describing pendulum systems are nonlinear and we provide analytical and numerical results regarding interpretation about the amplitude and the phase of signals in different pendulum settings. We report an explicit solution of the Elastic Pendulum problem in the case of linear phase. We develop an experimental procedure to piece-wise approximate bounded functions on a partition …

Mathematical And Statistical Modeling With Deep Neural Networks, Albert Romero

Theses and Dissertations

General adversarial networks (GANs) are a form of machine learning that includes two neural networks competing in a zero-sum game. One network produces artificial, while the other tries to distinguish artificial data from real. The Wasserstein general adversarial network with gradient penalty (WGAN-GP) variant of this technique is used to produce solutions for ordinary and partial differential equations.

A Gpu Accelerated Genetic Algorithm For The Construction Of Hadamard Matrices, Raven I. Ruiz

Theses and Dissertations

Hadamard matrices are square matrices with +1 and -1 entries and with columns that are mutually orthogonal. The applications include signal processing and quantum computing. There are several methods for constructing Hadamard matrices of order 2k for every positive integer k. The Hadamard conjecture proposes that there are also Hadamard matrices of order 4k for every positive integer k. We use a genetic algorithm to construct (search for) Hadamard Matrices. The initial population of random matrices is generated to have a balanced number of +1 and -1 entries in each column. Several fitness functions are implemented exploiting …

A Decomposition Formula For The Multi-Soliton Solutions To The 'Good' Boussinesq Equation, Aldo Gonzalez

Theses and Dissertations

In this thesis, we relate multi-soliton waves generated by the 'good' Boussinesq equation to the distribution functions in the classical linear Schrödinger equation. The linear Schrödinger equation describes the distribution of a particle or particles in a particular environment. The Schrödinger equation is linear, the superposition principle of the solutions, especially the eigenfunctions is nonlinear and we will show that we may observe similar behavior in the solutions of the Boussinesq equations for soliton waves. The work extends the study of two-soliton solutions to the Boussinesq equation to the case of three-soliton solutions. …

Iterated Rascal Triangles, Jena M. Gregory

Theses and Dissertations

We introduce a sequence of number triangles, {Ri} i=0 infty , such that the entries of each share a common generalized recurrence relation. R1 is the Rascal triangle and as i grows large, Ri becomes Pascal's triangle. For all i, we provide a combinatorial interpretation and find closed-term formulas for the entries of Ri . Our proofs rely on generating functions and other combinatorial arguments.

Hardware Isolation Approach To Securely Use Untrusted Gpus In Cloud Environments For Machine Learning, Lucas D. Hall

Theses and Dissertations

Machine Learning (ML) is now a primary method for getting useful information out of the immense volumes of data being generated and stored in society today. Useful data is a commodity for training ML models and those that need data for training are often not the owners of the data leading to a desire to use cloud-based services. Deep learning algorithms are best suited to run on a graphical processing unit (GPU) which presents a specific problem since the GPU is not a secure or trusted piece of hardware in the cloud computing environment.

In this paper, we will analyze …

Hydrologic Modeling Study To Determine Hydrologic Impact Of Resacas On The Lower Laguna Madre Watershed, Antonio L. Reyna

Theses and Dissertations

During a high intensity storm events, a series of catastrophic events occur. These catastrophic events include flooding and destruction of infrastructure. Engineers have determined a method to design for high intensity storms based off hydrologic analysis of previous storms. With this data engineers can determine the outflow of major rivers and streams that may impact infrastructure. By determining the watershed engineers can predict the flow of the water and as well as the location of the outfall. In the Rio Grande Valley, water quality is very important because after rain events stormwater from cities is carried out towards the Laguna …

Structural Analysis Of [Ni(Dippe)] Fragment Using Computational Methods, Jennifer L. Sanchez

Theses and Dissertations

The structural analysis of the Nickel (Bisdiisopropylphospino)ethane, also known as [Ni(dippe)H]2, has been heavily studied in our group in collaboration with William D. Jones's group. A computational analysis of the [Ni(dippe)] fragment was performed to determine the structural relationship between the nickel center and its phosphine ligand, due to phosphines having both electronic and steric properties. The reactivity of the Nickel will be most dependent on the dippe ligand. A conformational search generated 244 conformers after a thorough minimization using Molecular Mechanic (MM) calculations where a thorough minimization was performed and then re-minimized using a SEED command until unique conformers …