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Full-Text Articles in Physical Sciences and Mathematics

Black Tio2 Nts And Zno-Tio2 Nts Heterostructure: Synthesis, Characterization, And Synchrotron-Based Spectroscopy Studies, Lu Yao Apr 2024

Black Tio2 Nts And Zno-Tio2 Nts Heterostructure: Synthesis, Characterization, And Synchrotron-Based Spectroscopy Studies, Lu Yao

Electronic Thesis and Dissertation Repository

The one-dimensional (1D) TiO2 nanotubes (NTs), and their derivatives have been extensively studied due to their potential use in water-splitting, solar cells, and lithium-ion batteries. Since TiO2 has a large band gap (~3.2 eV for anatase), there has been a search for higher photocatalytic efficiency by shifting the band gap into the visible range. This thesis presents a study of black TiO2 NTs and ZnO-TiO2 heterostructures using synchrotron-based X-ray spectroscopy and X-ray diffraction techniques. It involves the transformation from as-prepared TiO2 NTs to black TiO2 NTs via an electrochemical reduction method. ZnO-TiO2 NT …


5675 Wiredcats Scouting Hub, Sebastian Smiley Apr 2024

5675 Wiredcats Scouting Hub, Sebastian Smiley

Honors Theses

The WiredCats Scouting Hub was created to provide FIRST team 5675 with an application that allows them to make more informed strategic decisions regarding their competitive play. The app synthesizes data from multiple sources, parsing multiple data formats into a single source of truth. It also presents data to users through graphs and charts and provides interactive tables. The application meets the requirements set forth by the leadership of team 5675, effectively providing the capabilities they seek.


Kalamazoo Nature Center Mobile Application, Jacob Tebben Apr 2024

Kalamazoo Nature Center Mobile Application, Jacob Tebben

Honors Theses

This project aimed to address the challenge of enhancing visitor engagement and information dissemination at the Kalamazoo Nature Center (KNC) through the development of an integrated mobile and desktop application system. This initiative arose due to the limitations posed by traditional mobile applications which often become outdated and need to be updated by a dedicated software team. This project was designed for any user of the KNC desktop app to be able to update content on the mobile app, without the need of a dedicated software team.

The mobile application was designed for visitor use, enabling them to access up-to-date …


The Generation Of Terahertz Light And Its Applications In The Study Of Vibrational Motion, Aldair Alejandro Apr 2024

The Generation Of Terahertz Light And Its Applications In The Study Of Vibrational Motion, Aldair Alejandro

Theses and Dissertations

Terahertz (THz) spectroscopy is a powerful tool that uses ultrashort pulses of light to study the properties of materials on picosecond time scales. THz light can be generated through a variety of methods. In our lab, we generate THz through the process of optical rectification in nonlinear optical (NLO) organic crystals. THz light can be used to study several phenomena in materials, such as spin precession, electron acceleration, vibrational and rotational motion. The work presented in this dissertation is divided into two parts: (1) the generation of THz light and (2) applications of THz light. The first portion of this …


Multifunctional And Moisture Tolerant Zinc-Based Mono- And Bi-Metallic Metal-Organic Framework (Mof) Thin Films, Emmanuel Agbata Apr 2024

Multifunctional And Moisture Tolerant Zinc-Based Mono- And Bi-Metallic Metal-Organic Framework (Mof) Thin Films, Emmanuel Agbata

Theses and Dissertations

Many applications of metal-organic frameworks (MOFs) are highly dependent on their structures. The type and consistency of structure inform their properties. Zinc-based MOFs are applicable in different fields because of the low toxicity of zinc materials and are therefore also useful for catalysis. While MOF-5, a zinc-based MOF with carboxylate linkers is moisture intolerant, a variant of this is moisture tolerant. The introduction of a nitrogen-based linker in the zinc MOF which renders the structure moisture-tolerant. This material has not been explored as much, despite its multifunctional properties. Furthermore, the growth of Zn-based bimetallics of this MOF has not yet …


On Properties Of Pair Operations, Sarah Jane Poiani Apr 2024

On Properties Of Pair Operations, Sarah Jane Poiani

Mathematics & Statistics ETDs

For any closure operation $\cl$ and interior operation $\ri$ on a class of $R$-modules, we develop the theory of $\cl$-prereductions and $\ri$-postexpansions. A pair operation is a generalization of closure and interior operations. Using Epstein, R.G. and Vassilev's duality \cite{ERGV-nonres}, we show that these notions are in fact dual to each other. We discuss the relationship between the core and hull and prereductions and postexpansions. We further the thematic notion of duality and seek to understand how it arises in the context of properties pair operations can be endowed with and focus on inner product spaces and properties demonstrated by …


A New Effective Gravitational Lensing Approach To Constrain Dark Matter, Birendra Dhanasingham Apr 2024

A New Effective Gravitational Lensing Approach To Constrain Dark Matter, Birendra Dhanasingham

Physics & Astronomy ETDs

Galaxy-scale strong gravitational lenses offer a unique window into understanding the nature and distribution of dark matter at sub-galactic scales. Beyond the main-lens subhalos, the inclusion of line-of-sight dark matter halos has become essential in lens studies due to their substantial role in perturbing lensed images, making multi-plane lensing a crucial aspect of any lens study. We highlight that these line-of-sight halos appear extended tangentially along the lensing critical line in the effective convergence maps due to the nonlinear nature of multiplane lensing, resulting in a characteristic anisotropic signature in the deflection field. Leveraging tools from large-scale structure analyses, this …


Comprehensive Question And Answer Generation With Llama 2, Matous Hybl Apr 2024

Comprehensive Question And Answer Generation With Llama 2, Matous Hybl

MS in Computer Science Theses

Since the introduction of transformers, large language models have proven capable in many natural language processing fields. However, existing systems still face challenges in generating high-quality extractive questions. Base models and public chatbots fall short if the question source or quantity are critical. Our contribution is a question and answer generator for generating comprehensive, extractive questions and answers. This approach includes fine-tuning a LLaMA 2 base model for answer extraction (AE) and question generation (QG). We evaluate the resulting system using common automated metrics and a manual evaluation. We find that our system is comparable to the latest research and …


Mathematically Rigorous Deep Learning Paradigms For Data-Driven Scientific Modeling, Owen Nicholas Davis Apr 2024

Mathematically Rigorous Deep Learning Paradigms For Data-Driven Scientific Modeling, Owen Nicholas Davis

Mathematics & Statistics ETDs

This dissertation explores the crucial role of data-driven modeling in science and engineering, with a focus on developing surrogate models to accelerate large-scale computational tasks, aiding in both outer-loop functions like uncertainty quantification and expensive inner-loop tasks within broader computational frameworks. Challenges arise with increased problem dimension and sparse, noisy training data, particularly significant when constructing surrogates for very expensive computational models where acquiring sufficient high-fidelity training data is unfeasible. In such scenarios, training surrogates from an ensemble of multifidelity information sources of varying accuracy and cost becomes essential. We emphasize neural network-based modeling paradigms, which are flexible in integrating …


The Black-To-White Hole Transition, Farshid Soltani Apr 2024

The Black-To-White Hole Transition, Farshid Soltani

Electronic Thesis and Dissertation Repository

Classically, an isolated black hole is a stable gravitational object. If however semiclassical effects are taken into account, an isolated black hole can be shown to slowly radiate its mass away in a process called evaporation. At the end of the evaporation process, when the size of the horizon becomes Planckian, the quantum nature of the gravitational field can no longer be neglected and the dynamics of the horizon is governed by quantum gravity. The main objective of this thesis is the systematic investigation of a tentative scenario for the “end of the life” of a black hole: the black-to-white …


Context-Aware Affective Behavior Modeling And Analytics, Md Taufeeq Uddin Apr 2024

Context-Aware Affective Behavior Modeling And Analytics, Md Taufeeq Uddin

USF Tampa Graduate Theses and Dissertations

Affective computing (AC) is a sub-domain of AI that has the potential to assist people by assessing mental states and making appropriate recommendations to patients, loved ones, caregivers, and domain experts. Humans usually produce an enormous amount of data (such as face videos) every day. One of the major challenges for affective computer vision is to efficiently deal with high volumes of data to facilitate automated model development. To cope with this challenge, we developed computer vision algorithms that measure the expressivity of the human face from video data. More precisely, the developed algorithms can map complex affect information from …


Feed More, Waste Less, Kaitlyn Dietz Apr 2024

Feed More, Waste Less, Kaitlyn Dietz

Honors Projects

With college prices and the cost of food increasing, so has the rate of food insecurity among college students. Food insecurity is defined as the lack of availability or access to food to meet someone’s basic and necessary needs. Food insecurity is associated with lower grades, depression, higher perceived stress, and lower graduation rates. Campuses across the country are responding to the problem in a variety of ways, including distribution of food directly to students through food pantries. Meal plans are expensive in the addition to college tuition and housing. The lowest cost for a meal plan at Bowling Green …


The Mathematical And Historical Significance Of The Four Color Theorem, Brock Bivens Apr 2024

The Mathematical And Historical Significance Of The Four Color Theorem, Brock Bivens

Honors Theses

Researching how the Four Color Theorem was proved, its implications on the mathematical community, and interviews with working mathematicians to develop my own personal opinions on the significance of the Four Color Theorem.


A Precise Measurement Of The Lifetime Of B-Mesons, Measurement Of Cp-Violation Parameters Of Bs-Mesons, The Atlas Experiment At The Lhc, And Development Of Silicon Detectors For Future Particle Physics Experiments, Easwar Anand Narayanan Apr 2024

A Precise Measurement Of The Lifetime Of B-Mesons, Measurement Of Cp-Violation Parameters Of Bs-Mesons, The Atlas Experiment At The Lhc, And Development Of Silicon Detectors For Future Particle Physics Experiments, Easwar Anand Narayanan

Physics & Astronomy ETDs

A series of connected research projects has been carried out for the purpose of seeking physics phenomena beyond the Standard Model. These consist of a precise measurement of the lifetime of a short-lived b-hadron, the Bd-meson; preparations for measurements of CP-violating parameters in Bs decays; development of triggers that select b-hadron events; development of new instruments for improved precision in detecting fundamental particles; and monitoring and mitigating the effect of radiation on the detectors, which is inescapable in their operating environment. Datasets collected by the ATLAS detector at the Large Hadron Collider (LHC) are used for …


Quantum Computation Using Large Spin Qudits, Sivaprasad Thattupurackal Omanakuttan Apr 2024

Quantum Computation Using Large Spin Qudits, Sivaprasad Thattupurackal Omanakuttan

Physics & Astronomy ETDs

This dissertation explores quantum computation using qudits encoded into large spins, emphasizing the concept of quantum co-design to harness the unique capabilities of physical platforms for enhanced quantum information processing. First, we delve into the generation of high-fidelity universal gate sets for quantum computation with qudits. Leveraging principles from quantum optimal control, Rydberg physics, and the atomic structure of alkaline-earth atoms, we propose protocols for high-fidelity universal gate sets in the ground state of 87Sr with reasonable experimental parameters. Next, we analyze schemes to encode a qubit in the large spin qudits for fault-tolerant quantum computation (FTQC). By comprehending …


Luminescence And Structural Properties Of Silicon-Germanium Quantum Structures Fabricated By Ion Implantation, Matheus Coelho Adam Apr 2024

Luminescence And Structural Properties Of Silicon-Germanium Quantum Structures Fabricated By Ion Implantation, Matheus Coelho Adam

Electronic Thesis and Dissertation Repository

The advancement of semiconductor materials has played a crucial role in driving positive technological breakthroughs that impact humanity in numerous ways. The presence of defects significantly alters the physical properties of semiconductors, making their analysis essential in the fabrication of semiconductor devices. I presented a new method to quantify surface and near-surface defects in single crystal semiconductors. Epitaxially-grown silicon was measured by low energy electron diffraction (LEED) to obtain the surface Debye temperature (θD). The results showed the surface θD of bulk Si (001), 1.0 μm, and 0.6 μm Si on sapphire of 333 K, 299 K, …


Post-Modeling Adjustments And Delivered Dose Verification Of The 6fff Beam Model Commissioned For The Monaco Treatment Planning System, Grant C. Debevec Apr 2024

Post-Modeling Adjustments And Delivered Dose Verification Of The 6fff Beam Model Commissioned For The Monaco Treatment Planning System, Grant C. Debevec

LSU Master's Theses

External beam radiation therapy has been shown to be an effective treatment method for tumors and abnormalities of the spine and vertebral region. Treating the spine using a stereotactic body radiation therapy (SBRT) technique can reduce toxicity to the spinal cord. The 6 MV flattening filter free (6FFF) beam model is currently used to plan and calculate dose for SBRT treatment plans, and the treatment plans are delivered using a linear accelerator (LINAC).

The commissioned beam model represents an invariant component of a LINAC. For volumetric modulated arc therapy (VMAT) treatment plans, the multileaf collimator (MLC) positions are changing throughout …


Quandle Rings, Idempotents And Cocycle Invariants Of Knots, Dipali Swain Apr 2024

Quandle Rings, Idempotents And Cocycle Invariants Of Knots, Dipali Swain

USF Tampa Graduate Theses and Dissertations

Quandles are sets with self-distributive binary operations that axiomatize the three Reidemeister movesin classical knot theory. In an attempt to bring ring theoretic techniques to the study of quandles, a theory of quandle rings analogous to the classical theory of group rings where several interconnections between quandles and their associated quandle rings have been explored. Functoriality of the construction implies that morphisms of quandle rings give a natural enhancement of the well-known quandle coloring and quandle 2 cocycle invariant of knots and links.

The dissertation is structured into two main parts. In the first part, we delve into quandle rings …


All-Optical Probes Of Particle-Like Charge Migration Dynamics, Kyle A. Hamer Apr 2024

All-Optical Probes Of Particle-Like Charge Migration Dynamics, Kyle A. Hamer

LSU Doctoral Dissertations

Particle-like charge migration (CM) is the coherent, back-and-forth motion of a positively-charged electron hole along the backbone of a molecule following a sudden ionization. CM in small molecules generally occurs on an Angstrom (10-10 m) spatial scale and an attosecond (10-18 s) timescale. I use time-dependent density-functional theory (TDDFT) to simulate CM modes in organic molecules, and to explore all-optical probes of this attosecond electron dynamics using high-harmonic spectroscopy (HHS). By leveraging my results from previous studies of two-center interferences in carbon dichalcogens, in which I separated the harmonic signal into contributions from individual Kohn-Sham orbitals, I first …


Estimating Crustal Thickness In Northwest Louisiana Using The Receiver Function Method, Delton Samuel Apr 2024

Estimating Crustal Thickness In Northwest Louisiana Using The Receiver Function Method, Delton Samuel

LSU Master's Theses

I aim to constrain the crustal thickness of the Sabine Block in the Sabine Uplift region of northwest Louisiana, using the frequency domain receiver function deconvolution technique followed by H-κ stacking. The passive margin on the southern edge of the North American continent experienced an active tectonic history, including the spreading events that led to the formation of the Gulf of Mexico. A previous study proposed the Sabine Block is a residual fragment of Proterozoic orogenic origin; however, its full extent and geometry are up for debate. It is now overlain by thick sedimentary sequences ranging from ~4-6 km deposited …


Reducibility Of Schrödinger Operators On Multilayer Graphs, Jorge Villalobos Alvarado Apr 2024

Reducibility Of Schrödinger Operators On Multilayer Graphs, Jorge Villalobos Alvarado

LSU Doctoral Dissertations

A local defect in an atomic structure can engender embedded eigenvalues when the associated Schrödinger operator is either block reducible or Fermi reducible, and having multilayer structures appears to be typically necessary for obtaining such types of reducibility. Discrete and quantum graph models are commonly used in this context as they often capture the relevant features of the physical system in consideration.

This dissertation lays out the framework for studying different types of multilayer discrete and quantum graphs that enjoy block or Fermi reducibility. Schrödinger operators with both electric and magnetic potentials are considered. We go on to construct a …


Finite Monodromy And Artin Representations, Emma Lien Apr 2024

Finite Monodromy And Artin Representations, Emma Lien

LSU Doctoral Dissertations

Artin representations, which are complex representations of finite Galois groups, appear in many contexts in number theory. The Langlands program predicts that Galois representations like these should arise from automorphic representations and many examples of this correspondence have been found such as in the proof of Fermat's Last Theorem. This dissertation aims to make an analysis of explicitly computable examples of Artin representations from both sides of this correspondence. On the automorphic side, certain weight 1 modular forms have been shown to be related to Artin representations and an explicit analysis of their Fourier coefficients allows us to identify the …


The Modular Generalized Springer Correspondence For The Symplectic Group, Joseph Dorta Apr 2024

The Modular Generalized Springer Correspondence For The Symplectic Group, Joseph Dorta

LSU Doctoral Dissertations

The Modular Generalized Springer Correspondence (MGSC), as developed by Achar, Juteau, Henderson, and Riche, stands as a significant extension of the early groundwork laid by Lusztig's Springer Correspondence in characteristic zero which provided crucial insights into the representation theory of finite groups of Lie type. Building upon Lusztig's work, a generalized version of the Springer Correspondence was later formulated to encompass broader contexts.

In the realm of modular representation theory, Juteau's efforts gave rise to the Modular Springer Correspondence, offering a framework to explore the interplay between algebraic geometry and representation theory in positive characteristic. Achar, Juteau, Henderson, and Riche …


Exploration Of Characteristic Curve In Fox Float 3 Shock Dampers To Expedite Shock Damp Tuning., Joshua R. Moore Apr 2024

Exploration Of Characteristic Curve In Fox Float 3 Shock Dampers To Expedite Shock Damp Tuning., Joshua R. Moore

Honors College Theses

The shock absorber is an integral part of a vehicle suspension system and has a strong influence on its performance, especially in the case of motorsports. It is important to study the force versus velocity relationship, commonly known as the characteristic curve of the shock absorber both during compression and rebound. Vendor-supplied characteristics often reflect the behavior of the shock absorber in a particular setting. However, during the installation, the settings inside the shock absorber are adjusted to increase the human comfort level and performance of the vehicle. This may change the characteristic curve of the shock. The available data …


Beach Processes Controlling Erosional Hotspots And Their Influences On Beach Nourishment Performances: A Case Study Along West-Central Florida Barrier Island Beaches, Sophia Gutierrez Apr 2024

Beach Processes Controlling Erosional Hotspots And Their Influences On Beach Nourishment Performances: A Case Study Along West-Central Florida Barrier Island Beaches, Sophia Gutierrez

USF Tampa Graduate Theses and Dissertations

This study examines the long-term performance of repeated beach nourishment over an approximately 35-year period at two barrier islands, Sand Key and Treasure Island along the west-central Florida coast, USA. Five cycles of beach nourishment on Sand Key and six on Treasure Island were conducted during the study period. Three erosional hotspots were identified along a combined 14-km stretch of the nourished beach. The processes that cause the erosional hotspot were examined through numerical modeling of nearshore wave and current fields.

The most recent three nourishments since 2006 were monitored systematically by this study. Beach profiles were surveyed bimonthly to …


Subroups Of Coxeter Groups And Stallings Foldings, Jake A. Murphy Apr 2024

Subroups Of Coxeter Groups And Stallings Foldings, Jake A. Murphy

LSU Doctoral Dissertations

For each finitely generated subgroup of a Coxeter group, we define a cell complex called a completion. We show that these completions characterizes the index and normality of the subgroup. We construct a completion corresponding to the intersection of two subgroups and use this construction to characterize malnormality of subgroups of right-angled Coxeter groups. Finally, we show that if a completion of a subgroup is finite, then the subgroup is quasiconvex. Using this, we show that certain reflection subgroups of a Coxeter are quasiconvex.


Comparative Analysis Of Time Series Models On U.S. Stock And Exchange Rates: Bayesian Estimation Of Time Series Error Term Model Versus Machine Learning Approaches, Young Keun Yang Apr 2024

Comparative Analysis Of Time Series Models On U.S. Stock And Exchange Rates: Bayesian Estimation Of Time Series Error Term Model Versus Machine Learning Approaches, Young Keun Yang

USF Tampa Graduate Theses and Dissertations

This study presents a comparative analysis of contemporary applications of time series models, focusing on the Bayesian approach. In contrast to many nonparametric studies, the Bayesian approach circumvents the common issue of bandwidth selection by offering systematic estimation and avoiding ad hoc methods. Specifically, we delve into the Bayesian approach for estimating the autocovariance function of a time series model’s error term. Traditional time series models often make the unrealistic assumption of a constant error term. Furthermore, models such as autoregressive conditional heteroskedasticity (ARCH) and general autoregressive conditional heteroskedasticity (GARCH) address the limitation of constant variance by assuming an autoregressive …


Analytic Wavefront Sets Of Spherical Distributions On The De Sitter Space, Iswarya Sitiraju Apr 2024

Analytic Wavefront Sets Of Spherical Distributions On The De Sitter Space, Iswarya Sitiraju

LSU Doctoral Dissertations

In this work, we determine the wavefront set of certain eigendistributions of the Laplace-Beltrami operator on the de Sitter space. Let G′ = O1,n(R) be the Lorentz group, and let H′ = O1,n−1(R) ⊂ G′ be its subset. The de Sitter space dSn is a one-sheeted hyperboloid in R1,n isomorphic to G′/H′. A spherical distribution is an H′-invariant eigendistribution of the Laplace-Beltrami operator on dSn. The space of spherical distributions with eigenvalue λ, denoted by DλH'(dSn), has dimension 2. We construct a basis for the space of …


A Petrological Characterization Of The Iutzi Member Of Lucas Formation, Michigan Basin, Moira Burns Apr 2024

A Petrological Characterization Of The Iutzi Member Of Lucas Formation, Michigan Basin, Moira Burns

Honors Theses

It is thought that most Phanerozoic dolomites form via the replacement of precursor calcium carbonate [CaCO3] with dolomite [CaMg(CO3)2] through a dissolution-precipitation reaction with a Mg-bearing fluid. Although this may be widely accepted, the timing, conditions, settings, and mechanisms associated with the dolomitization process are still strongly debated, resulting in the proposal of various dolomitization models. The association between evaporite minerals and dolomite in the rock record is common and has led many to propose a model genetically associating evaporative fluids and dolomitization. The evaporative model posits as marine fluids evaporate and become more …


Navigating Murky Waters: State-Level Strategies For Wetland Preservation And Tile Drainage Regulation After Sackett V. Epa, Caleb M. Swanson Apr 2024

Navigating Murky Waters: State-Level Strategies For Wetland Preservation And Tile Drainage Regulation After Sackett V. Epa, Caleb M. Swanson

Honors Thesis

Wetlands are some of the world’s most valuable ecosystems, serving as provisioners of species habitat, carbon sequestration, flood mitigation, water quality purification, and other ecosystem services. Human development has resulted in substantial wetland loss the world over. In the 1970s, the United States Congress passed the Clean Water Act, giving the EPA broad authority over wetland protection. However, in the summer of 2023, the United States Supreme Court decided Sackett v. EPA, limiting the EPA’s jurisdiction over wetlands to those indistinguishably connected to generally recognized “Waters of the United States” and removing federal protection for millions of acres of wetlands, …