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Concrete Oasis: Measures of Accessibility & Equity in the Distribution of Public-Serving Amenities Across U.S. Cities
No full textThe phrase Concrete Oasis offers an oxymoronic depiction of the modern city: a vast industrial landscape, replete with competition and inequality, yet one simultaneously over-flowing with resources and amenities holding the potential to improve the public good. From libraries and parks to hospitals and schools, these entities provide economic, social, and
health-related benefits for city residents.
In this thesis, I investigate whether those amenities actually reach all city residents by mapping the geographical accessibility of each resource to both household income and racial identity. I further derive correlations that describe how distributions of each amenity type vary nationally using property data from the 38 most populous U.S. cities. I then test three historical factors—partisanship, latitude, and city founding date—to explore plausible origins for resource and spatial inequality.
Through a combination of large-scale graph analysis and sociological theory, my research reveals that the majority of amenities are most accessible for wealthier and whiter neighborhoods, but also investigates potential middle class neglect and the relative lack of amenities in racially integrated areas. I propose partisanship and latitude as possible historical contributors to inequitable amenity distributions with respect to income, and city founding date to those with respect to race. Finally, I discuss approaching future urban planning through a lens of redistributive inequality as a means to establish long-term structural support of amenities for those who need them most.Computer Scienc
Jewel Beetle Ornament: Art, Animals, and Power in East Asia, 5th–8th Centuries
No full textIn premodern East Asia, animals that display vivid colors supplied some of the rarest, most precious materials for making sumptuous artifacts. Funerary and Buddhist artifacts from Japan and Korea dated to the period between the fifth and the eighth centuries preserve a decorative technique that uses the exoskeletons of jewel beetles (Chrysochroa fulgidissima), a species native to East Asia known for its stunning iridescence. Collected from dispersed habitats and lavished on artifacts reserved for the upper echelons of society, the jewel-like insects disclose the complex interrelationships of art, animals, and power that underpin the history of ornamentation. Such interrelationships remain largely underexplored in existing scholarship, which primarily treats the decorative use of insects as a material and technical feature of historical artifacts with little relevance for understanding their social function or cultural meaning. This dissertation draws on methodologies from material culture studies, ecocritical art history, and animal-human studies to reframe the history of jewel beetle ornament against the backdrop of the rise of centralized states, increased interregional connectivity, and intensified exploitation of natural resources. Instead of treating jewel beetle ornaments as mere embellishments, I approach them as compelling examples of how animals and humans embedded in their shared ecologies shaped the production and consumption of elite artifacts during a transformative period in East Asian history.
The dissertation is organized into two parts. Part I, “Materials and Making,” consists of two chapters that follow the movement of jewel beetles from their habitats in broadleaf forests to artisans’ workshops and elite patrons’ collections, examining jewel beetles as vital things with unique physical and optical properties and environmental settings that shape human interactions with them. Part II, “Ornament and Power,” is organized as three case studies of extant artifacts with jewel beetle ornaments that delve into how the physical, sensory, and symbolic presence of animals empowers objects to mediate social interactions and ritual experiences. Together, the two parts of the dissertation use jewel beetle ornament as an analytical thread to interweave discussions of a diverse corpus of prestige goods, funerary art, and Buddhist ritual paraphernalia. By focusing on the materiality and insectile origin of beetle ornaments, this project elucidates the entanglement of animals and animal bodies in the construction and expression of power within political and religious contexts.History of Art and Architectur
Combining Analytical, Numerical, and AI Models to Improve Cloud and Convection Representation in Climate Simulations
No full textAccurate representation of small-scale processes, such as convection and cloud formation, remains one of the greatest challenges in climate modeling, even in kilometer-scale storm-resolving simulations. These processes are essential for determining large-scale atmospheric behavior, but computational constraints prevent their full representation in global climate models. For instance, deep convection may not exhibit convergent behavior with increasing resolution, and significant uncertainties persist in ice microphysics parameterization. This thesis explores these challenges in two parts: the first (Chapters 2 and 3) examines how small-scale convection and cloud processes influence large-scale atmospheric states in idealized radiative-convective equilibrium simulations, while the second (Chapter 4) investigates machine learning (ML) as a tool for efficiently emulating these processes in climate models.
Chapter 2 addresses a fundamental question: what controls the vertical thermal structure of an equilibrium atmosphere? To answer this, I developed a refined zero-buoyancy plume model that analytically solves equilibrium atmospheric profiles given boundary conditions. The model highlights how plume-environment mixing influences vertical temperature profiles, upper-tropospheric convective mass flux, and cloud fraction. These findings align with convection-permitting simulations, which reveal that higher horizontal resolution---acting as a proxy for enhanced plume-environment mixing---leads to increased cloud fraction and mass flux in the upper troposphere.
Chapter 3 explores the impact of microphysics scheme uncertainties on equilibrium atmospheric states, particularly focusing on deep convective overshoots into the tropical tropopause layer (TTL). We find that different microphysics schemes produce distinct heat balance regimes in the TTL. Two schemes lead to a “hard-landing” scenario, where frequent, strong convective overshoots induce significant cooling (~0.2 K day−1), while a third scheme results in a “soft-landing” scenario, with weaker overshoots and minimal cooling (~0.03 K day−1). This difference arises from variations in upper-tropospheric stratification driven by atmospheric cloud radiative effects (ACRE). The scheme producing the soft-landing scenario generates stronger ACRE, leading to a ~3K warmer, more stable upper-tropospheric layer that buffers convective updrafts.
Chapter 4 demonstrates how ML can emulate these small-scale processes efficiently by learning directly from high-resolution simulations. Using data from superparameterized climate simulations, we train ML models to replace the embedded cloud-resolving models. While previous studies show that such hybrid ML-physics simulations can reproduce key climate statistics, they often suffer from online instability, particularly in setups with real geography and explicit cloud condensate coupling. By integrating an expressive U-Net architecture with cloud microphysics constraints, we achieve stable and skillful multi-year hybrid climate simulations with realistic cloud climatology and explicit cloud condensate coupling.Earth and Planetary Science
Exploring Axion physics in quantum materials via magnetoelectric coupling
No full textAxion, a hypothetical particle in high-energy physics, was originally proposed to solve both the strong CP problem in quantum chromodynamics and the dark matter problem. Due to its extremely weak interaction with ordinary matter, the Axion has remained elusive despite decades of searches. In electromagnetism, Axion physics introduces an additional E · B term to Maxwell’s equations, which couples electric and magnetic fields. In condensed matter physics, this framework finds an analog in the magnetoelectric coupling of topological materials. In vacuum or conventional materials, an electric field induces electrical polarization, while a magnetic field generates magnetization—typically without cross-coupling between the two. However, beyond this paradigm, certain novel materials could exhibit magnetoelectric coupling, where an electric field induces magnetization (M = αE) or a magnetic field induces electric polarization (P = αH). The magnetoelectric effect is commonly observed in a special class of wide-bandgap magnetic insulators, known as magnetoelectric or multiferroic insulators (e.g., Cr₂O₃ and BiFeO₃), where the effect arises from localized magnetic ions. More recently, theoretical advances have predicted fundamentally new types of magnetoelectric coupling in topological materials—systems characterized by nontrivial topological invariants and Berry curvature. Unlike conventional insulators, these materials can support robust dissipationless edge states and exhibit magnetoelectric phenomena rooted in their topological electronic structure. In particular, magnetic topological insulators provide a platform where magnetism and topology intertwine, giving rise to rich physics, including a quantized magnetoelectric coefficient in topological insulators, Axion quasiparticles in antiferromagnetic (AFM) topological insulators, and the chiral anomaly in magnetic Weyl semi-metals.
In this thesis, we present several experimental discoveries, uncovering the unique magnetoelectric effect in magnetic topological material. First, we investigate the optical magnetoelectric effect in the prototypical AFM topological insulator MnBi₂Te₄, which enables unique reflection circular dichroism in an antiferromagnet. Furthermore, we achieved the optical control of the antiferromanetic order by circularly polarized light for the first time. Both the optical detection and control could be understood within the framework of optical Axion electrodynamics. Next, we report the direct observation of the Axion quasiparticle in MnBi₂Te₄, which is a condensed matter analog of the dark matter Axion. Using ultrafast optical pump-probe techniques, we observe coherent oscillations of the magnetoelectric coefficient α in MnBi₂Te₄, which is the smoking-gun evidence for the Axion quasiparticles. Microscopically, the Axion quasiparticle is enabled by magnon-induced Berry curvature modulation. The observed Axion quasiparticle not only can serve as a simulator for the elusive dark matter Axion, but it could also serve as a potential Axion detector, providing a novel path for dark matter detection. Lastly, we shift our focus to explore the magnetoelectric coupling in a magnetic Weyl semimetal CeAlSi. Firstly, we uncover a broadband nonlinear optical diode effect (NODE) in CeAlSi, where the magnetization induces a pronounced directional asymmetry in the optical second-harmonic generation (SHG). DFT calculations also show that this broadband NODE effect originates from the Weyl fermions. By applying an electrical current, we further explore the magnetoelectric coupling in this magnetic Weyl semimetal, in which we discover the electric control over the magnetic domains.Chemistry and Chemical Biolog
Stereogram Arcade: Applied illusions of depth perception in a video game
No full textStereopsis is the brain’s ability to fuse together the flat and slightly-differing images from each eye into a rich, three-dimensional understanding of space. Autostereograms – images tailored to evoke stereopsis and reveal a 3D scene when viewed with deconverged or “unfocused” eyes – have unique and engaging entertainment value, as demonstrated by the success of the Magic Eye picture book series, but thus far they have been overwhelmingly constrained to the printed, static realm. Autostereographic video games present a unique medium for interactive, animated, 3D entertainment.
This thesis has two parts. First, an analysis of game design constraints is presented, with considerations for games intended to be viewed autostereographically, focusing on color and peripheral vision. Second, the design and implementation of a series of autostereogram games that use a custom, real-time autostereogram shader with performance and visual optimizations. This thesis builds upon prior work in developing autostereogram generation algorithms. Prior research discovered several visual optimizations, such as removing false artifacts and directional bias, but still suffered from low-resolution slope discrepancies. Different prior research has achieved real-time rendering speeds using hardware acceleration, but relied on methods that induced visual errors. This game expands on and combines both the performance and visual optimizations. Specifically, slope smoothing and real-time compute shader parallelization are novel optimization techniques for autostereogram generation.Computer Scienc
On Self and Nonself A Case Study of the Cytosolic LPS Sensor Caspase-11
No full textThe cornerstone of immunology lies in the distinction between Self and Non-self, where the immune system must differentiate threats (Non-Self) from innocuous elements (Self) to trigger appropriate responses. Traditionally, this dichotomy has been conceptualized as a mutually exclusive relationship, where Non-Self is defined as the absence of Self. Within this classical framework, autoimmune diseases represent aberrations, and immune tolerance toward tumors is seen as a failure of the immune system.
This thesis explores an alternative framework, proposing that recognition of Self is a prerequisite for recognizing Non-self. In this model, recognition of endogenous ligands, which can be loosely defined as “Self” in the traditional framework, provides a contextual basis for the immune system to fine-tune its responses.
Focusing on caspase-11, traditionally described as a sensor for cytosolic lipopolysaccharide (LPS)—a molecule exclusively associated with Gram-negative bacteria—this thesis uncovers the molecular mechanisms underlying caspase-11's ligand recognition. Furthermore, it identifies the self-equivalent of LPS, shedding light on the duality of Self and Non-Self in immune recognitionMedical Science
The View from Nowhere: Travels Through the Peripheries of Pine Biomass in Georgia
No full textConfronted by escalating planetary environmental crises, the global demand for "green" energy solutions has paradoxically intensified historically extractive practices in peripheral regions. This dissertation studies one such case: pine biomass in the Southeastern United States. Pine biomass is often misrepresented as a carbon-neutral energy source, and its production relies on patterns of social and environmental appropriation inherited from plantation systems established in the 18th and 19th centuries.
By foregrounding the role of pine as both an industrial commodity and an arboreal tool of enclosure, this dissertation demonstrates how military, carceral, and logistical landscapes are fragmented, reclassified, and concealed under “greening” agendas to stake political claims to ecology. The View from Nowhere mobilizes an experimental geographic methodology that combines political ecology, environmental history, and critical realist filmmaking to move between scalar frames, from the situated to the systemic. The aim is to interrogate the epistemic frameworks and visual paradigms that render these landscapes inevitable and invisible, with the purpose of illuminating crucial opportunities for reconfiguring our engagements with land, labor, and ecology.
At stake is not only an alternative representation of energy transition, but a broader critique of the spatial and economic models that structure our understanding of crises. Through bottom-up accounts of socio-natural processes in Georgia, The View from Nowhere – and its film component, Under Story – resist the dominant technocratic view of “the planetary” as an object of totality and instead seeks to reawaken its productive tensions and inevitable distances. Ultimately, these paradigm shifts seek to assert the political agency of subjects embedded within socio-spatial transformations.Advanced Studies Progra
Engineering an Open-source Motion Capture Platform to Characterize Abnormal Gaits for Resource-limited Environments
No full textGait abnormalities, a leading cause of death for older adults, are on the rise with the increasing
global median age. While existing technologies can detect and quantify these abnormalities,
their limited use in low-resource settings due to high costs and limited interoperability
poses a severe challenge. This thesis overcame that barrier by introducing a novel approach:
an open-source motion capture tool. The paper details creating a color-based marker detection
system that utilizes a Kalman filter for tracking and the methods for achieving 3D
marker coordination using a stereovision setup. The paper determined the necessary rotation
matrices to obtain physiologically relevant angles utilizing a series of markers placed at
anatomically relevant reference points. The motion capture system was validated by characterizing
and classifying four gaits at three different speeds across two participants. The paper
employed the motion capture system to assess the key features of normal, crouch, spastic,
and steppage gaits in both the time and frequency domains. The paper performed spline
interpolation, principal component analysis (PCA), linear discriminant analysis (LDA), logistic
regression, support vector machine (SVM), and k-nearest neighbor (KNN). The paper
found that nonlinear statistical methods slightly outperformed linear ones when classifying
gait. The paper showed that using the frequency domain can mitigate the impact of temporal
noise during windowing and provide a more effective approach to classifying speed.
The paper demonstrated that individually trained models have little generalizability, but
increasing the population over which model training occurs can mitigate this concern.Engineering Sciences A
Dead Center: Nishkama kama in the Bhagavad Gita and elite athletic performance
No full textThis thesis aims to uniquely contribute to our understanding of how the central
idea of the Bhagavad Gita, nishkama kama, may be most beneficially integrated into
global sports performance psychology to help unlock the mindset and mental framework
behind some of the most successful performers on the global stage.
Concepts of desirelessness, non-attachment and duty can play a fundamental role
for athletes but remain understudied. This study of the rich dimensions of nishkama kama
aims to travel to corners rarely visited by scholars in the field to date who have mostly
focused on influencing thoughts rather than detaching from them entirely and articulating
values rather than defining a greater sense of personal purpose, duty or sacrifice towards
a greater cosmic being, God or otherwise. Dimensions of desirelessness, non-attachment
and sacrifice in service of duty can be found present among some of the highest athletic
achievers of the last century, but scholarship incorporating them in a framework for peak
performance has yet to be significantly developed. The thesis hypothesizes that
employing these dimensions to athletic endeavors can be linked to achieving
extraordinary results.
Contemporary meta-studies and systematic studies of the sports psychology
landscape were surveyed to understand the state of the art. From this, two dominant
models were extracted to act as base line comparators for the hypothesis, Positive
Psychology and the Mindfulness Acceptance and Commitment models. Various
interpretations by leading scholars of nishkama kama were then surveyed before applying
the most appropriate interpretation for our purposes. A Nishkama Kama Model for Peak
Performance is then presented, supported by evidence from leading practitioners, both
athletes and coaches, in the field. The notion of staying 'dead center' (as Kobe Bryant puts
it) as well as underscoring the power of a larger purpose behind an athlete’s ‘why’ are
potentially powerful techniques to enhance the elite sports psychology landscape that
warrant more research and understanding to continue to advance the field.Extension Studie
Music as a Medium: Resistance and Embodied Relationships in On Earth We’re Briefly Gorgeous
No full textIn On Earth We’re Briefly Gorgeous, Ocean Vuong employs music as a narrative
device that mirrors trauma, memory, identity formation. The novel uses music as a
narrative device to reflect the fragmented process of working through trauma,
establishing intimate relationships with others, and forging personal identity. Music helps
explore trauma, memory, and identity specifically as an effect of The Vietnam War and
heteronormativity. Through ethnomusicology, literary studies within the historical
context of the Vietnam War, and an examination of the Vietnamese diasporic, this
research analyzes how music in the novel mirrors the characters’ lived experiences and
establishes their sense of self. Music challenges traditional national memory and serves as
an alternative medium to uplift marginalized voices. While music in On Earth We’re
Briefly Gorgeous depicts a personal account of trauma, the literature research highlights
pervasive gaps in recorded histories which supports a persistent need for artists to
continue their work creating various mediums that encapsulate a multifaceted narrative
account of events.Extension Studie