Digital Commons Network^™

The Density Distribution Of The Material Around Betelgeuse, Iman Behbehani

Dissertations, Theses, and Capstone Projects

Betelgeuse is a red supergiant star visible in the constellation Orion. Its windy and highly convective surface results in a complicated mass loss pattern difficult to understand and replicate in simulations. The ejected mass can form a shell around the star we consider the circumstellar material (CSM). In this study, we use ALMA interferometric observations to find the structure of Betelgeuse's CSM, and connect to the mass loss mechanisms that could form it. We measure a bipolar circumstellar structure with a position angle of 42.3$\pm 7.0^\circ$. We observe asymmetries in the form of hot spots in the north east of …

The Spaces Between: A Phenomenological Exploration Of Classical Music Performance Practice, Fifi Zhang

Dissertations, Theses, and Capstone Projects

In his theory of duration, the philosopher Henri Bergson (1859-1941) asserts that the present moment is “both a perception of the immediate past and a determination of the immediate future…a joint system of sensations and movements.” In an ideal musical performance, this sensori-motor apparatus guides every one of the performer’s decisions on stage, resulting in an aural experience that is spontaneous, visceral, and deeply personal. In practice, much of today’s classical music performance culture, which relies heavily on visual notation and prioritizes fidelity to the composer’s intent, is antithetical to fundamental artistic values such as creativity, individual self-expression, and direct …

Origin And Maintenance Of The Andean Bird Fauna, Elkin A. Tenorio

Dissertations, Theses, and Capstone Projects

The origin and maintenance of the tropical montane diversity have been evaluated over multiple decades using various techniques and perspectives. Despite major progress in understanding phylogenetic relationships, diversification patterns, distributional data, and general ecology in the Andean biota, large gaps in our understanding remain, particularly in the synthesis across scales. To fill these gaps, I aimed to explore patterns and processes that underlie species diversification in birds of the tropical Andes of South America by combining different approaches using phenotypic, phylogenetic, and genomic data in multiple temporal and spatial scales.

In the first chapter, I examined the macroevolutionary patterns of …

The Question Of Money: State, Protest, And Informal Currencies In The Wake Of Greece’S Economic Crisis, Helen Panagiotopoulos

Dissertations, Theses, and Capstone Projects

Monetary unions are designed to foster political, social, and economic integration among member states by enabling the free movement of people, goods, services, and capital. Yet when a member nation faces economic crisis, citizens may respond by creating monetary systems of their own. This research asks whether such practices are simply demonstrations of human resiliency and adaptability, or whether they also challenge the very idea of a shared market and currency that do not align with national identity. Greece offers a crucial case for this inquiry. Following the 2008 debt crisis, austerity measures led to economic depression, mass unemployment, and …

Nonlinear Diffusion, Hydrodynamic Cascades And Jamming In Kinetically Constrained Systems: Insights From Lattice Gas Models, Abhishek Raj

Dissertations, Theses, and Capstone Projects

This dissertation investigates non-linear diffusion processes and emergent dynamical phenomena in kinetically constrained lattice gases. Two central models are considered: a one-dimensional lattice gas exhibiting a diffusion cascade triggered by hydrodynamic nonlinearities and a triangular ladder exclusion model that undergoes a jamming transition. The former demonstrates stretched exponential decay consistent with non-perturbative long-time tails, while the latter illustrates how classical-quantum mappings yield insight into glassy dynamics and mobility constraints. Through a combination of numerical simulations, analytical perturbation theory, and mean-field approximations, the work uncovers mechanisms underlying anomalous transport, jamming transitions, and the breakdown of perturbative hydrodynamics.

Nonlinear Optics Through Femtosecond Light-Matter Interactions, Shah Faisal B. Mazhar

Dissertations, Theses, and Capstone Projects

This dissertation offers experimental and theoretical insights into nonlinear light-matter interactions induced by intense femtosecond (fs) laser pulses. It investigates key phenomena, including stimulated Raman scattering (SRS) from phonon and magnon quasiparticles, supercontinuum (SC) generation via self-phase modulation (SPM), conical emission (CE) arising from four-wave mixing (4WM), and modulation instability (MI) driven by cross-phase modulation (XPM) between SRS and SC processes. These effects are studied in diverse media using state-of-the-art femtosecond lasers.

The interplay among SRS, SC, 4WM, and MI is examined to probe vibrational modes and temperature-dependent magnetic excitations in condensed-matter systems. Experiments are conducted on anisotropic uniaxial calcite …

Leveraging Stellar Chemistry For A Global View Into The Atmospheres Of Brown Dwarfs And Giant Exoplanets, Emily Calamari

Dissertations, Theses, and Capstone Projects

In the era of the James Webb Space Telescope (JWST), it is now possible to examine substellar mass atmospheres in unparalleled detail and precision. However, unraveling the complicated thermodynamics and chemistry in these atmospheres remains a challenge. Atmospheric retrievals are a leading data-driven technique capable of recovering an object’s fundamental parameters such as mass, radius, effective temperature, gravity, cloud structure and composition and chemical abundances. However, in directly imaged or isolated worlds, constraining and/or interpreting these fundamental parameters can be difficult, particularly as retrieval models try to parameterize the overall impact of clouds.

For my dissertation, I turned to main …

Multi-Nuclear Magnetic Resonance (Nmr) Characterization Of Novel Materials, Tawhid Pranto

Dissertations, Theses, and Capstone Projects

The increasing reliance on batteries in commercial products, coupled with the environmental challenges posed by climate change and the limitations of fossil fuel consumption, has created strong financial and environmental incentives to explore innovative energy storage solutions. Renewable energy sources are being actively developed, but their intermittent nature necessitates efficient storage technologies, driving significant research into improving the performance of batteries, fuel cells, and capacitors.

This thesis focuses on the application of advanced Nuclear Magnetic Resonance (NMR) spectroscopy to study and understand novel materials for energy storage applications, with an emphasis on electrolytes for rechargeable lithium-ion batteries and all-solid-state batteries. …

The Effect Of Tbi On Working Memory And Anxiety In Rats, Mariola Sobolewska

Dissertations, Theses, and Capstone Projects

Traumatic Brain Injury (TBI) is a significant public health concern, often leading to cognitive and emotional impairments. This study examined the effects of TBI on working memory and anxiety-like behavior in young male Sprague-Dawley rats using the Radial Arm Maze (RAM) and Elevated Plus Maze (EPM), which are behavioral assessments. The RAM tests spatial working memory by evaluating the animal’s ability to remember and efficiently navigate multiple arms to retrieve rewards. The EPM assesses anxiety-like behavior based on the animal’s preference for open versus closed arms. The study utilized young male Sprague-Dawley rats, a well-established rodent model known for its …

Text-Based Propaganda Detection, Vivek Sharma

Dissertations, Theses, and Capstone Projects

In the digital age, the swift consumption of news and the widespread dissemination of propaganda significantly threaten democratic principles and informed decision-making. News organizations, often aligned politically, tailor their content to appeal to specific audiences, thereby perpetuating biases. Despite advancements in detecting propaganda through various computational techniques, including Large Language Models(LLM) and BERT-based approaches, significant challenges persist concerning data availability and the effectiveness of detection tools. This thesis explores the landscape of text-based propaganda and reviews related research in textual analysis. It introduces a novel method for collecting a social-media based dataset, which includes analysis of journalists' tweets to discern …

Re-Envisioning Digital Agency: From Representationalism To Interpretant-Driven Epistemology, Michael C. Lee

Dissertations, Theses, and Capstone Projects

This thesis examines the epistemological and ethical foundations of digital technologies, particularly code and algorithmic systems, by considering their entanglement with representationalism. Arguing that code now functions as a dominant social agent and epistemic subject, through the concept of the Code’s-eye view, I explore how automated datafication reduces human experience to quantifiable inputs, reinforcing epistemic closure and social fragmentation. Drawing on pragmatist philosophy, including Peirce’s semiotics, Dewey’s democratic ethics, and Rorty’s conversational inquiry, I propose an interpretant-driven epistemology grounded in communal inquiry and interpretive openness. This alternative framework resists the binary logic of algorithmic rationality by emphasizing conflict and the …

Effect Of Equation Of State On The Formation Of Binary Black Holes In Active Galactic Nucleus Disks, Theodore Edwards

Dissertations, Theses, and Capstone Projects

Active galactic nucleus disks have been proposed as a possibly dominant location of the mergers of binary black holes detected by gravitational wave observatories. The nonlinear interactions between stellar mass black holes and disk gas determine when binaries will form from single objects on nearby orbits. Prior work has used smoothed particle hydrodynamics models in an isothermal disk to study this problem. However, the local equation of state near the midplane of an optically thick accretion disk is adiabatic rather than isothermal, even if the radiative equilibrium temperature is azimuthally isothermal. Therefore, we investigate the use of an adiabatic equation …

Wavelength And Luminance Interaction On Spatio-Temporal Contrast Sensitivity Function, Taylan S. Ergun

Dissertations, Theses, and Capstone Projects

Contrast sensitivity (CS) measures the ability to discriminate objects from their backgrounds under varying conditions(Campbell & Robson, 1968). Contrast sensitivity is important for navigating the real world and operating under different light conditions. The contrast sensitivity function (CSF) reflects how the visual system performs under different conditions. This measure is crucial in assessing the health of the visual system (Chen & Gardner, 2021). CSF contributes to a deeper understanding of how the visual system processes and integrates properties of light to create visual sensation and perception. Human contrast sensitivity depends on the viewing conditions such as field size, luminance, color, …

Developments In The Lithographic Engineering Of Bi2sr2cacu2o8+Delta Mesa Terahertz-Emitting Devices, Sarah Elghazoly

Dissertations, Theses, and Capstone Projects

Devices microfabricated from the high-temperature superconducting cuprate Bi₂Sr₂CaCu₂O_8+𝛿 (Bi-2212) are a promising source of coherent terahertz radiation within the ’terahertz gap’ (0.3- 1.5 THz). A current-biased mesa patterned into the surface of a single crystal will produce electromagnetic radiation in the terahertz regime due to the naturally occurring Josephson junctions formed by the stacks of superconducting cuprate oxide planes in the material separated by insulating BiO and SrO barrier layers. Previous research has shown that by fabricating these mesas such that the geometry supports resonant cavity Fabry-Perot modes, the junctions within the mesa …

The Role Of Water In Peptide Behavior And Peptide-Based Water-Responsive Crystals, Janel Jannette Rivera Cancel

Dissertations, Theses, and Capstone Projects

Water plays a crucial role in shaping the behavior and function of biomolecules across the liquid, supercooled, and glassy states. This thesis presents a dual approach combining computational simulations and experimental investigations to explore the influence of water on biomolecular systems, particularly peptide-based materials. We employ molecular dynamics simulations to study the hydration-dependent structural dynamics of homopolymer peptides. Simulations were carried out across a range of temperatures and pressures to analyze changes in hydration and structural stability, shedding light on the behavior of peptides under supercooled and glassy conditions. These studies are especially relevant for understanding biomolecular stability in cryopreservation. …

Satellite-Host Galaxy Co-Evolution With Next-Generation Regulator Models, Austen Gabrielpillai

Dissertations, Theses, and Capstone Projects

The evolution of satellites galaxies is an unsolved problem in galaxy formation. Recent observations such as the SAGA and ELVES surveys find tension in HI contents and star formation of satellites around their central host galaxies when compared to our own local environment, the Milky Way. These processes are potentially highly influenced by the host's circumgalactic medium (CGM), and to constrain these cases requires accurate and fast modeling of satellites-host interactions. In this work, we present our methodology for evolving z = 0 surviving satellites alongside their central galaxy in sapphire, a CGM regulator co-evolution model of galaxy formation. …

Tradition, Individuality, And Innovation In Western Classical Music Performance: A Quantitative Analysis Of Bach’S Fourth Cello Suite Prelude, Clare Monfredo

Dissertations, Theses, and Capstone Projects

Why do we seek out new performances of a commonly performed piece of music? An essential tradition of Western classical music (WCM) is the performance of canonical works by composers, an activity that requires the interpretation and execution of written scores by individual performers. In this practice, performers are not only expected to determine the composer’s “intentions,” but also somehow (paradoxically) share these in a “unique” performance interpretation. In musical education, performers are trained by teachers to create these “unique” interpretations by learning how to intuit composers’ intentions in a system that passes down interpretative traditions through master-apprentice one-on-one lessons. …

Coding Anti-Discrimination Jurisprudence: A Hybrid Computational Model Of The Arlington Heights Test, Kevin S. Jobe

Philosophy Faculty Publications

The aim of this study is to understand the judicial reasoning process of anti-discrimination jurisprudence by utilizing a hybrid computational model. The advancement of hybrid computational legal studies that combine “law-as-code” and “law-as-data” approaches have led to promising techniques for tackling complex legal reasoning tasks as multifactor judicial reasoning standards. Following this hybrid model, this study conducts a statistical and multilayer perceptron (MLP) analysis of the judicial reasoning process of the multifactor Arlington Heights discriminatory purpose test based on an original hand-coded dataset of discrimination cases. The results of the study show that “sequence of events” predominates the other factors …

Futurescape Libraries Ai Toolkit, Keith Webster

Copyright, Fair Use, Scholarly Communication, etc.

A toolkit developed to explore scenario-specific strategies and activities that research libraries can undertake to prepare for various possible AI-influenced futures. The toolkit integrates the ARL/CNI AI Scenarios published in spring 2024 along with priorities trialed and refined by strategic thinkers working directly in, or adjacent to, the research library field during a Strategic Implications forum held December 7–8, 2024, in Washington, DC.

Missing The Mark: The Cost Of Overlooking Black Students’ Cultural Capital, Christine L. Quince

Teacher Education

Historically, educators and policymakers have viewed Black students from a deficit lens, often presuming they lack the necessary skills needed to become academically successful. Today, teachers have countered deficit framing of Black students by learning more about and incorporating Black students’ assets and critical views of the world into their learning. One issue teachers run into, however, is knowing how to incorporate Black students’ cultures in their classroom learning. Using an embedded case study, this study analyzes how one white teacher draws on Black students’ cultural capital and the ways it impacts students’ classroom experiences. Findings reveal that disconnecting Black …

Nocturnal Foraging By Great Blue Heron (Ardea Herodias) And Roseate Spoonbill (Platalea Ajaja), Laura E. Josler, Johnny E. Owens, Sarrah E. Bristol, Leo N. Dutkewych, Abigail R. Kauke, Signe E. Renstrom, Ben G. Sheffield, Madelyne E. Vashaw, Avery J. Nesbitt, Melia K. Paat, Timothy D. Bransford, Elizabeth A. Forys

Florida Field Naturalist

The Great Blue Heron (Ardea herodias) and Roseate Spoonbill (Platalea ajaja) are long-legged wading birds that can forage throughout a 24-hour cycle. Nocturnal foraging enables these species to take advantage of optimal foraging conditions and reduced competition. This study aims to investigate how environmental factors influence the nocturnal foraging behavior of these species. To monitor foraging activity, we deployed 17-18 infrared cameras from dusk until dawn from 4 October 2023 to 24 July 24 2024, covering two sampling periods across different habitats within Fort De Soto County Park, a barrier island complex in Tampa Bay, Florida. We compared the frequency …

Frsc 359-003: Physical Methods Of Forensics, Kevin Parmelee

Chemistry, Environmental and Forensic Science Syllabi

No abstract provided.

Physics-Based Machine Learning Framework For Predicting Structure-Property Relationships In Ded-Fabricated Low-Alloy Steels †, Atiqur Rahman, Md Hazrat Ali, Asad Waqar Malik, Muhammad Arif Mahmood, Frank Liou

Mechanical and Aerospace Engineering Faculty Research & Creative Works

The Directed Energy Deposition (DED) process has demonstrated high efficiency in manufacturing steel parts with complex geometries and superior capabilities. Understanding the complex interplays of alloy compositions, cooling rates, grain sizes, thermal histories, and mechanical properties remains a significant challenge during DED processing. Interpretable and data-driven modeling has proven effective in tackling this challenge, as machine learning (ML) algorithms continue to advance in capturing complex property structural relationships. However, accurately predicting the prime mechanical properties, including ultimate tensile strength (UTS), yield strength (YS), and hardness value (HV), remains a challenging task due to the complex and non-linear relationships among process …

Learning Orientation Field For Osm-Guided Autonomous Navigation, Yuming Huang, Wei Gao, Zhiyuan Zhang, Maani Ghaffari, Dezhen Song, Cheng-Zhong Xu, Hui Kong

Research Collection School Of Computing and Information Systems

OpenStreetMap (OSM) has gained popularity recently in autonomous navigation due to its public accessibility, lower maintenance costs, and broader geographical coverage. However, existing methods often struggle with noisy OSM data and incomplete sensor observations, leading to inaccuracies in trajectory planning. These challenges are particularly evident in complex driving scenarios, such as at intersections or facing occlusions. To address these challenges, we propose a robust and explainable two-stage framework to learn an Orientation Field (OrField) for robot navigation by integrating LiDAR scans and OSM routes. In the first stage, we introduce a novel representation, OrField, which can provide orientations for each …

Preference-Based Deep Reinforcement Learning For Historical Route Estimation, Boshen Pan, Yaoxin Wu, Zhiguang Cao, Yaqing Hou, Guangyu Zou, Qiang Zhang

Research Collection School Of Computing and Information Systems

Recent Deep Reinforcement Learning (DRL) techniques have advanced solutions to Vehicle Routing Problems (VRPs). However, many of these methods focus exclusively on optimizing distance-oriented objectives (i.e., minimizing route length), often overlooking the implicit drivers' preferences for routes. These preferences, which are crucial in practice, are challenging to model using traditional DRL approaches. To address this gap, we propose a preference-based DRL method characterized by its reward design and optimization objective, which is specialized to learn historical route preferences. Our experiments demonstrate that the method aligns generated solutions more closely with human preferences. Moreover, it exhibits strong generalization performance across a …

On The Chlorobenzene-Ammonia Cluster Reaction: Entrance Channel Dynamics, 2cr2pi Spectroscopy, And Ion Imaging Of The Reaction Dynamics, Ronald Mutete, Damian Kokkin, Natan Fessahaye, Thomas R. Howell, Richard A. Loomis, Scott A. Reid

Chemistry Faculty Research and Publications

Prior studies of halobenzene–ammonia complexes have shown that the nature of the cationic intermediate (i.e., Wheland-type vs ion-radical) may play a key role in determining the reaction products. To probe this link, we report here the reaction dynamics of the chlorobenzene-ammonia 1:1 complex (PhCl···NH₃) using product ion imaging following two-color resonant two-photon ionization. A threshold value of 8.863 ± 0.008 eV was determined for the appearance of protonated aniline, which accompanies Cl atom loss and is the dominant product channel at energies near threshold. Scanning down to energies close to threshold, we find no evidence for a roaming …

Wind Turbine Rotor Design Using High-Fidelity Aerostructural Optimization, Marco Mangano, Sicheng He, Yingqian Liao, Denis-Gabriel Caprace, Andrew Ning, Joaquim R. R. A. Martins

Faculty Publications

Large wind turbines yield more energy but demand careful aeroelastic blade design. Coupled multiphysics design strategies can reduce wind energy costs exploiting fluid-structure interactions. This work presents the first high-fidelity aerostructural optimization study of a large wind turbine rotor.We use blade-resolved fluid dynamics and structural solvers in a monolithic gradient-based optimization framework to explore steady-state torque and blade mass trade-offs. The coupled-adjoint approach computes gradients efficiently, enabling the optimization of over 100 structural and geometric parameters simultaneously. Our optimization study modifies a DTU 10 MW benchmark with a simplified structure and isotropic material properties. The tightly coupled optimizations increase torque …

Indigenous Women’S Reproductive Traditions: Reclaiming Sovereignty Through 500 Years Of Colonization, Stephanie A. Sellers

Gettysburg College Faculty Books

In Indigenous Women’s Reproductive Traditions, Stephanie Sellers delves into the rich history of Indigenous women’s reproductive practices before European colonization. The book highlights traditional methods such as birth control, abortion, and child spacing, which were integral to maintaining agency over their bodies. Sellers explores how these practices were disrupted by European patriarchal structures and examines the impact of forced sterilization in the 20th century. Today, Indigenous women are reclaiming their rights through movements for reproductive justice, advocating for a return to their ancestral practices and redefining concepts of womanhood and motherhood on their own tribal terms.

Neutrosophic Probabilistic And Statistical Extensions Of The Neutromultispace Model For Blended Teaching Process In University Physical Education: A Novel Neutrosophic Modeling Framework, Guoquan Lin, Hongtao Guo, Ying Zheng

Neutrosophic Sets and Systems

No abstract provided.

The Cosmoverse White Paper: Addressing Observational Tensions In Cosmology With Systematics And Fundamental Physics, Eleonora Di Valentino, Jackson Levi Said, Adam Riess, Agnieszka Pollo, Vivian Poulin, Adrià Gómez-Valent, Elena Giusarma, Et Al.

Michigan Tech Publications

The standard model of cosmology has provided a good phenomenological description of a wide range of observations both at astrophysical and cosmological scales for several decades. This concordance model is constructed by a universal cosmological constant and supported by a matter sector described by the standard model of particle physics and a cold dark matter contribution, as well as very early-time inflationary physics, and underpinned by gravitation through general relativity. There have always been open questions about the soundness of the foundations of the standard model. However, recent years have shown that there may also be questions from the observational …