Physical Sciences and Mathematics Commons^™

Using Machine Learning To Track The Location Of The Shock Train In Hypersonic Engines, Alison Reynolds

Undergraduate Honors Theses

Proposed hypersonic vehicles would be able to travel at five to ten times the speed of sound, but there are still many problems that need to be solved to construct a functioning vehicle. One such problem involves shocks created in the engine isolator when the vehicle reaches high speeds. These shocks must be contained to the isolator to maximize performance and avoid potential failure. This project attempts to track the location of the leading shock given images of airflow from ground tests of engines using random forests and convolutional neural networks. When the models are trained and tested on data …

Contentious Vulnerability: Infrastructure, Assemblages, And Environmental Justice Communities, Mads Emmett

Undergraduate Honors Theses

Charles City County, Virginia has been the target of several large developmental proposals in recent years. Two of these proposed projects, the C4GT and Chickahominy natural gas power stations, have faced opposition from residents of Charles City County and people across the state who are concerned about the environmental impacts and health risks associated with fossil fuel infrastructure. These proposed power plants are part of an extensive assemblage of infrastructure: an uneven built network of physical and affective relationships brought together through contingencies which involves human and non-human parts and facilitates the distribution of resources and people around the world …

Composite Gravity In Curved Spacetime, Austin Batz

Undergraduate Honors Theses

This work presents the development of a quantum theory of gravity motivated by diffeomorphism-invariance and background-independence. A composite graviton state that satisfies the linearized Einstein’s field equations has been identified via perturbative expansion about a curved vacuum spacetime. The emergence of this gravitational interaction is discussed, as well as cancellation of tadpoles and treatment of ultraviolet divergences via dimensional regularization. In other words, the formalism of quantum field theory is used to identify a gravitational interaction as an emergent phenomenon rather than as a fundamental aspect of nature. The lattice is proposed as a candidate for a physical regulator, and …

Economic Feasibility Of Mixed Plastic Waste Pyrolysis Using Twin Reactor System In Northwest Arkansas, Carol Rogers, Patricia Means, Renato Gonzalez, Kaida Sheets, Hayden Townsend

Chemical Engineering Undergraduate Honors Theses

Plastic waste generation is increasing at an unsustainable rate while recycling solutions remain stagnant. As a chemical means of recycling, mixed plastic waste pyrolysis can generate synthetic oil appropriate for use as fuel in power generation from plastic waste that otherwise accumulates in landfills. With the scaling of a commercial plastic pyrolysis process in Northwest Arkansas (NWA) modeled after an operational sawdust pyrolysis unit in Huntsville, Arkansas, economic analysis resulted in 26.3% internal rate of return. Therefore, construction of a commercial mixed plastic-to-fuel pyrolysis plant is economically justified and should be pursued. To effectively implement the proposed design, NWA must …

Effects Of The Transportation And Climate Initiative On The Maine Economy: An Analysis Of Cap-And-Invest And Its Heterogeneous Impacts On Rural And Urban Households, William L. Somes

Honors College

In December 2020, a memorandum of understanding (MOU) was released by the Transportation and Climate Initiative Program (TCI-P), a collaboration of 13 jurisdictions in the New England and Mid-Atlantic regions of the United States. Modeled on the Regional Greenhouse Gas Initiative (RGGI), the TCI-P follows a cap-and-invest framework to reduce emissions from the transportation sector by 26% from 2022 to 2032. Since the TCI-P is expected to raise the price of gasoline by 5¢ to 9¢ per gallon, there has been concern that some populations may be disproportionately affected. The present research studies the potential heterogeneous impacts of the TCI-P …

Novel Optical Frequency Combs Injection Locking Architectures, Ricardo Bustos Ramirez

Electronic Theses and Dissertations, 2020-2023

Due to their highly stable timing characteristics, optical frequency combs have become instrumental in applications ranging from spectroscopy to ultra-wideband optical interconnects, high-speed signal processing, and exoplanet search. In the past few years, there has been a necessity for frequency combs to become more compact, robust to environmental disturbances, and extremely energy efficient, where photonic integration shows a clear pathway to bring optical frequency combs to satellites, airships, drones, cars, and even smartphones. Therefore, the development of chip-scale optical frequency combs has become a topic of high interest in the optics community. This dissertation reviews the work made in the …

Analyzing The Lysergic Acid Amide Content Extracted From The Seeds Of Argyreia Nervosa Via The Use Of Lc-Ms, Elisabeth Barone

Forensic Science Master's Projects

Psychedelic plant use by humans can be traced back centuries to the times when early cultures used these plants in activities ranging from healing rituals to religious ceremonies. In recent years, several of these plants have reemerged on the drug scene and are currently being marketed as “legal highs” (since the plant seeds are legal to purchase through a variety of online vendors). With the growing number of internet forums where recreational drug users can write about their experiences and share them with others, it has become relatively simple for almost anyone to obtain the materials necessary to experience a …

Treatment Of Prodcued Water Using Ferrate (Vi) And Directional Solvent Extraction, Sean X. Thimons

Water Resources Science and Technology Theses and Graduate Research Reports

Oil field fracking operations creates by-product “produced water” that is highly variable in composition and difficult to treat. This study aims to examine two novel treatment processes together in improving the quality of a synthetic, hypersaline produced water, and examines if effluent would be suitable for reuse. Here, we examine the ability of ferrate (VI) to coagulate organic and inorganic compounds to reduce turbidity while the efficacy of diisopropylamine (DIPA) in water extraction from the subsequent hypersaline solutions was also assessed under a variety of temperature ranges. For the final product water that is separated and treated through both processes, …

Kinetics For Enzymatic Conversion Of Biomass To Glucose, Jordan Broadwater

Undergraduate Honors Theses

Biofuels are a sought-after alternative for fossil fuels in today’s society. More specifically, cellulose-based biofuel is an avenue of research intending to limit waste and provide new renewable energy. Cellulose is a rigid polymer of glucose monomers that is found abundantly across different agriculture crops. However, its stability is a barrier to energy production from this source. Pretreatment followed by hydrolysis of cellulosic materials serves a potential to produce glucose to be used in biofuels in larger quantities compared to other methods. This project studied the effect microwave pretreatment and oxygenation have on hydrolysis of cellulose in Arundo Donax. Arundo …

How The Growth Of Technology Has Forced Accounting Firms To Put An Emphasis On Cybersecurity, Holden Halbach

Accounting Undergraduate Honors Theses

The advancement of technology has brought many changes to accounting firms. Computer applications such as Microsoft Excel have made calculators and physical spreadsheets obsolete. Then with the introduction of cloud computing employees can store, access, and exchange large amounts of data instantaneously from any location. These technological innovations have increased the accuracy and efficiency of firms substantially. However, this growth in technology has shown the importance of putting an emphasis on cybersecurity throughout the accounting industry. The emphasis placed on cybersecurity throughout accounting firms is more prevalent than any other industry. This is primarily because accounting firms not only deal …

Using Deep Learning To Analyze Materials In Medical Images, Carson Molder

Computer Science and Computer Engineering Undergraduate Honors Theses

Modern deep learning architectures have become increasingly popular in medicine, especially for analyzing medical images. In some medical applications, deep learning image analysis models have been more accurate at predicting medical conditions than experts. Deep learning has also been effective for material analysis on photographs. We aim to leverage deep learning to perform material analysis on medical images. Because material datasets for medicine are scarce, we first introduce a texture dataset generation algorithm that automatically samples desired textures from annotated or unannotated medical images. Second, we use a novel Siamese neural network called D-CNN to predict patch similarity and build …

Predicting Range Shifts For The Virginia Opossum In Maine, Sara Griffin

Honors College

Species distribution and movement are increasingly influenced by climate change and human expansion. The Virginia opossum (Didelphis virginiana) has been observed expanding their range northward due to the warming temperatures and urbanization. The Virginia opossums’ northern range is thought to be restricted by two abiotic winter factors, snow cover and low temperatures, which prevents foraging and ultimately leads to starvation. For this study, I predicted the movement of the Virginia opossum northward into central Maine and beyond based on current climate change trends. Microclimate temperatures were recorded using data-loggers and climate variable datasets were used to determine if …

Statistical And Variational Modeling And Analysis Of Passive Integrated Photonic Devices, Norbert Dinyi Agbodo

Legacy Theses & Dissertations (2009 - 2024)

The success of Si as a platform for photonic devices and the associated availabilityof wafer-scale, ultra-high resolution lithography for Si CMOS has helped lead to the rapid advance of Si-based integrated photonics manufacturing over the past decade. This evolution is nearing the point of integration of Si-based photonics together with Si-CMOS for compact, high speed, high bandwidth, and cost-effective devices. However, due to the sensitive nature of passive and active photonic devices, variations inherent in wafer-based fabrication processes can lead to unacceptable levels of performance variation both within a give die and across a given wafer. Fully understanding the role …

Examining The Benefits Of A Sustained Balance And Fall Prevention Programming For Independent Older Adults Living In A Community Setting, Noah Davis

Legacy Theses & Dissertations (2009 - 2024)

Falls have been an identified public health and social problem since the 1980’s and now recognized as a global health problem in many of the developed nations. The National Council on Aging and the Centers for Disease Control and Prevention acknowledge many evidence-based fall prevention programs. However, there are identified concerns to the programs; for example, a lack of sustained programming for older adults in the community setting. The literature review on fall prevention interventions identifies that few programs are sustained after two years, primarily due to a lack of funding and a lack of interest by older adults. However, …

Diagnosing High Sinuosity Regimes Associated With Anomalous Greenland Ice-Melt Events Using Self-Organizing Maps, Mansour El Riachy

Legacy Theses & Dissertations (2009 - 2024)

Sinuosity, a metric that describes the waviness of the circumpolar flow, is adapted to quantify modification of the tropospheric polar vortex within longitudinal sectors by localized incursions of warm, moist air from middle latitudes associated with Arctic cyclones (ACs). In this thesis, we identify four corridors of high AC track frequency, on which we center 90° longitudinal sectors comprising the following regions: Pacific, West of Greenland, Atlantic, and Asian. Sectorial sinuosity is calculated for the West of Greenland sector and is used to quantify the amplitude of the 300-hPa flow associated with anomalous Greenland ice-melt events.

Mining Subgroups From Temporal Data : From The Parts To The Whole, Alexander Gorovits

Legacy Theses & Dissertations (2009 - 2024)

A variety of dynamic systems can be broken down into potentially overlapping subcomponents with varying temporal behavior, ranging from communities in networks, to clusters of trajectories in spatiotemporal data, to co-evolving subsets within multivariate time series. Using explicit regularization on various temporal behaviors within a tensor factorizationframework, I demonstrate means to mine these subgroups along with their temporal activities, as well as how that yields information about the overall systems. Additionally, I adapt this notion of temporal communities to the spatiotemporal setting to develop a reinforcement learning approach for optimizing co-ordinated communication between independent agents.

A Project To Dye For : Differentiation Of Dyed And Non-Dyed Human Hairs Using Atr Ft-Ir Spectroscopy, Joseph John Greco

Legacy Theses & Dissertations (2009 - 2024)

IR spectroscopy is widely utilized for forensic purposes due to the chemical fingerprint the method provides. ATR FT-IR spectroscopy is particularly advantageous because it allows for spectra to be collected quickly, accurately, and perhaps most importantly for forensics, non-destructively. Human hair is commonly collected at a crime scene, and further analyzed using DNA analysis and microscopy. However, these techniques have limitations. In the past ATR FT-IR spectroscopy has shown promise in the analysis of human hair for forensic purposes. In this study, the differentiation of undyed hair versus dyed hair classes of varying colors based on their IR spectra were …

Associated Schemes Of Vertex Superalgebras And Equivariant Oriented Cohomology, Hao Li

Legacy Theses & Dissertations (2009 - 2024)

\begin{center}{\large \textbf{Part 1.}}\\ \vspace*{0.1cm} \end{center} We generalize the notion of "quasi-lisse" vertex algebras to the super case. The modularity of quasi-lisse vertex superalgebra (twisted)modules is discussed. We study several families of vertex operator superalgebras from an arc (super)space point of view. We provide new examples of vertex algebras which are "chiral-quatizations" of their $C_{2}$-algebras $R_V$. Our examples come from certain $N=1$ superconformal vertex algebras, Feigin-Stoyanovsky principal subspaces, Feigin-Stoyanovsky type subspaces, graph vertex algebras $W_{\Gamma}$, and extended Virasoro vertex algebras. We also give some counterexamples to the chiral-quatizations property. For principal subspaces, their characters are closely related to $q$-series identities. In …

Monitoring White-Tailed Deer Abundance And Habitat Selection In The Albany Pine Bush Preserve Using Unmanned Aerial Systems, Christopher Plummer

Legacy Theses & Dissertations (2009 - 2024)

Unmanned aerial systems (UAS) have seen recent advancements in technology that gave rise to their increasing use in recreational and commercial application, including wildlife conservation. Adaptive management is a must for wildlife conservation, with the goal of learning from management decisions to improve future management strategies, especially in the face of growing human related stressors such as climate change and habitat loss. Monitoring is a critical step for adaptive management, as it allows the manger to learn about the ecology of the natural system and quantify the impacts of management strategies. Species and habitats are frequently monitored for wildlife conservation …

Polymers In Drug Delivery Systems, Aashay Paresh Pratap

Legacy Theses & Dissertations (2009 - 2024)

Conventional drug delivery is associated with challenges such as low bioavailability, reduced half-life, nonspecific interactions, high immunogenicity, and degradation of drug before reaching the target. Modern drug delivery systems are designed to overcome the challenges of conventional drug delivery methods. Polymers play a crucial role in the development of modern drug delivery systems. Polymers form delivery vehicles that improve the therapeutic efficacy and reduce the side effects of a drug. Furthermore, it is possible to control the release of drug by using the delivery vehicles. Polymeric vehicles exist in different forms such as polymeric nanoparticles, hydrogels, and vesicles. Each form …

On The Structure And Phase Speeds Of The Kelvin Waves And Mjo Over The Indian Ocean, Ahmed Shaaban

Legacy Theses & Dissertations (2009 - 2024)

Kelvin waves in the stratosphere are well known to behave as radiative gravity waves. Yet, the tropospheric component of these Kelvin waves (and other tropical modes) has often been described as superpositions between the baroclinic modes. By decomposing the Kelvin waves into upward and downward-phase components, we found that only upward-phase Kelvin waves occupy the troposphere, indicating that the tropospheric Kelvin waves are not vertical standing oscillations as previously thought. Fast Kelvin waves were found to obey the structure of radiating gravity waves, like their stratospheric counterpart, more than the moist waves. The unexpected lack of variation in vertical tilt …

Topology Of The O(3) Non-Linear Sigma Model Under The Gradient Flow, Stuart Thomas, Christopher Monahan

Undergraduate Honors Theses

Quantum field theory is an extraordinarily successful framework that describes phenomena in particle physics and condensed matter. The O(3) non-linear sigma model (NLSM) is a specific theory used in both of these fields, describing ferromagnets and acting as a prototype for the strong nuclear force. It features topologically stable configurations known as instantons which cannot continuously evolve to the ground state. The topological susceptibility is a parameter that describes this stability and is predicted to vanish in physical theories, however numerical simulations find that the topological susceptibility diverges in the continuum limit. This issue has motivated the application of the …

Scenarios For Offshore Wind Power Production For Central California Call Areas, Yi-Hui Wang, Ryan K. Walter, Crow White, Matthew D. Kehrli, Benjamin Ruttenberg

Physics

In response to the growing interest in offshore wind energy development in California, the U.S. Bureau of Ocean Energy Management delineated three Call Areas for potential leasing. This study provides a comprehensive characterization and comparison of offshore wind power potential within the two Central California Call Areas (Diablo Canyon and Morro Bay) using 12-and 15-MW turbines under different inter-turbine spacing and wind farm size scenarios. Our analysis shows similar daily and seasonal patterns of wind power produced within the Call Areas, which peak in spring and during evening hours. Per-turbine power production is higher in the Morro Bay Call Area …

Synthesis And Self-Assembly Of Amphiphilic Block Copolymers For The Fabrication Of Non-Spherical Polymersomes, Tamuka Chidanguro

Dissertations

Polymersomes, also known as polymer vesicles, have gained a lot of interest over the past two decades. These hollow spherical systems are made via the self-assembly of amphiphilic block copolymers and have found use in a range of areas from drug delivery, to cellular models, to nanoreactors. Their hollow nature allows them to carry hydrophilic cargo in their inner compartment and hydrophobic cargo in their membrane. Over the last decade, increasing efforts have focused on controlling the morphology of polymersomes. Research has shown that polymersome morphology plays an important role for instance in drug delivery, where tubular or rod-like vesicles …

The Power Of Sulfur: A Study Of An Isothiocyanate Chiral Derivatizing Agent, Thioamide Based Chiral Solvating Agents, And The Geometry Of Sulfonamides, Emily B. Crull

Dissertations

This three-part dissertation is connected by the thread of utilizing sulfur-based functional groups, hence the power of sulfur. The first project was the development of a pentafluorobenzene based isothiocyanate chiral derivatizing agent (CDA), a class of compounds that differentiate enantiomers through covalent bond formation. This project, which was addressed using a combination of synthetic and computational methods and NMR analysis, gave rise to an CDA that was highly selective for amines and computationally predictable. Branching off of that, the second project demonstrated the use of two thioamide chiral solvating agents (CSAs), which had never been reported as a core functional …

A Component-Wise Approach To Smooth Extension Embedding Methods, Vivian Montiforte

Dissertations

Krylov Subspace Spectral (KSS) Methods have demonstrated to be highly scalable methods for PDEs. However, a current limitation of these methods is the requirement of a rectangular or box-shaped domain. Smooth Extension Embedding Methods (SEEM) use fictitious domain methods to extend a general domain to a simple, rectangular or box-shaped domain. This dissertation describes how these methods can be combined to extend the applicability of KSS methods, while also providing a component-wise approach for solving the systems of equations produced with SEEM.

Data-Driven Approaches To Complex Materials: Applications To Amorphous Solids, Dil Kumar Limbu

Dissertations

While conventional approaches to materials modeling made significant contributions and advanced our understanding of materials properties in the past decades, these approaches often cannot be applied to disordered materials (e.g., glasses) for which accurate total-energy functionals or forces are either not available or it is infeasible to employ due to computational complexities associated with modeling disordered solids in the absence of translational symmetry. In this dissertation, a number of information-driven probabilistic methods were developed for the structural determination of a range of materials including disordered solids to transition metal clusters. The ground-state structures of transition-metal clusters of iron, nickel, and …

Semantic Classification Of Multidialectal Arabic Social Media, Tom Rishel

Dissertations

Arabic is one of the most widely used languages in the world, but due in part to its morphological and syntactic richness, resources for automated processing of Arabic are relatively rare. Arabic takes three primary forms: Classical Arabic as seen in the Qur’an and other classical texts; Modern Standard Arabic (MSA) as seen in newspapers, formal documents, and other written text intended for widespread distribution; and dialectal Arabic as used in common speech and informal communication. Social media posts are often written in informal language and may include non-standard spellings, abbreviations, emoticons, hashtags, and emojis. Dialectal Arabic is commonly used …

Structural Origin Of Thermal, Mechanical Properties And Morphological Behaviors Of Semiconducting Polymers, Song Zhang

Dissertations

The past decades have witnessed a surging exploration of semiconducting polymers for the application of wearable and flexible organic electronic devices. Despite the increased amounts of molecular engineered polymers and their much-improved electrical performances, a systematic study of the structure-thermal/mechanical property-morphology relationship of semiconducting polymers is still less investigated.

To understand the thin-film mechanical properties, a pseudo-free standing tensile tester was self-built and utilized to obtain their real-time stress-strain behaviors through uniaxial stretching on top of the water surface. It also enables the first quantitative measurement of fracture energy on ultrathin polymeric films. Through multiple mechanical testing methods (i.e., strain-rate …

Efficient Denoising Of High Resolution Color Digital Images Utilizing Krylov Subspace Spectral Methods, Eva Lynn Greenman

Dissertations

The solution to a parabolic nonlinear diffusion equation using a Krylov Subspace Spectral method is applied to high resolution color digital images with parallel processing for efficient denoising. The evolution of digital image technology, processing power, and numerical methods must evolve to increase efficiency in order to meet current usage requirements. Much work has been done to perfect the edge detector in Perona-Malik equation variants, while minimizing the effects of artifacts. It is demonstrated that this implementation of a regularized partial differential equation model controls backward diffusion, achieves strong denoising, and minimizes blurring and other ancillary effects. By adaptively tuning …