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Toward a Unified Theory of Fire-Induced Spalling of Concrete: Transcending Domain Knowledge Limitations Through Explainable Artificial Intelligence, Causal Discovery and Inference
Get PDFWhen concrete is exposed to fire, it can suddenly break apart in a dangerous process called spalling. This can severely weaken buildings and even trigger a collapse. While researchers have studied this problem for years, we still don’t fully understand what causes it. My research uses a combination of data, and advanced AI techniques to identify and quantify the key factors that increase the risk of spalling. I collected data from over 1,000 fire tests and used AI models to predict when spalling might happen. I also applied explainable AI tools to understand why it happens.
The results showed that six key factors play a major role. These include how hot the fire gets, how strong the concrete is, how fast it heats up, the amount of moisture in the concrete, and whether it contains special fibers or additives. But prediction isn’t enough, we also need to understand cause and effect. To do this, I used causal AI techniques, which go beyond identifying patterns to uncovering which factors truly make spalling more or less likely. For example, I found that adding polypropylene fibers can reduce the risk of spalling by up to 31%, while too much moisture can increase the risk by more than 20%. These insights could help engineers design safer, more fire- resistant buildings and may eventually lead to clearer building code guidelines to prevent concrete failure in fires
The Intersection of Makeup and Recreation: A 21st Century Overview of Makeup Participation and Its Recreational Benefits
Get PDFThis dissertation critically reconceptualizes makeup participation as a legitimate, multidimensional form of recreation. Through a comprehensive rapid review using the SPIDER framework of 102 peer-reviewed studies published between 2000 and 2025, the research investigates whether and how makeup fulfills the psychological, affective, and symbolic criteria of meaningful leisure. Drawing on the Serious Leisure Perspective (SLP) and broader recreation theory, the study positions makeup not merely as aesthetic behavior or consumer habit, but as a sustained, emotionally generative practice embedded in identity, creativity, personal growth, and well-being.
Findings reveal that makeup is consistently linked to confidence-building, emotional regulation, self-expression, and psychological resilience, particularly among marginalized groups such as transgender individuals, cancer survivors, minority groups, and artists. Despite these benefits, fewer than 13% of studies explicitly classify makeup as leisure or recreation, underscoring a persistent conceptual blind spot. This dissertation addresses that gap by identifying seven core thematic categories, from “Self-Image and Confidence” to “Fun, Play, or Hobby,” which together illustrate makeup\u27s alignment with serious, casual, and project-based leisure forms.
The analysis also draws a novel historical throughline to the use of red ochre in prehistoric rituals, reframing early body adornment as one of the first symbolic and recreational acts in human history. In doing so, it asserts that play, beauty, and embodied expression are not ancillary to human evolution, they are foundational.
This work expands leisure theory to include appearance-based, affectively charged practices, and invites new interdisciplinary understandings of leisure that center aesthetic, emotional, and identity-based engagement. Implications span academic theory, therapeutic intervention, community programming, and cultural discourse. Ultimately, this research challenges enduring gendered and classed assumptions about what constitutes legitimate recreation and affirms that symbolic play, aesthetic autonomy, and the joy of adornment are not frivolous, they are serious and essential to human flourishing
Advancing Lithium-Ion Batteries Through Exploration of Novel Physico-Chemical Phenomena
No full textLithium-ion batteries (LIBs) power a wide range of modern devices, from smartphones to electric vehicles. This dissertation integrates materials characterization and electrochemical testing to develop novel Si-based electrode materials, investigate separator effects, and improve electrochemical impedance spectroscopy (EIS) modeling. First, I synthesized Si@CC composites using bio-based carbon sources and discovered a novel in situ disorder reduction in the amorphous carbon cloud during cycling, attributed to Si volume fluctuations and mesoporous carbon structure, which enhanced capacity retention. A binder-free electrode (Si@CC@BP) using bucky paper further improved gravimetric and areal capacities while reducing weight and manufacturing complexity.
Next, I investigated how separator polymer strand dynamics induce electrolyte advection, influencing dendrite-free metal plating, transference number measurements, and capacity oscillations. This work challenges the Bruce-Vincent method by showing that transference numbers depend on both electrolyte and separator and calls for a new parameter incorporating electrolyte flow.
Finally, I developed a Finite-Length Diffusion Equivalent Circuit Model (FLD-EECM) for EIS analysis, which captures mid- and high-frequency Warburg impedance effects overlooked by conventional models. This model provided more accurate estimates of key battery parameters, such as diffusion coefficients and charge transfer resistance, differing by over 5% from traditional methods.
Overall, my dissertation identifies novel phenomena and provides practical tools to improve the performance, reliability, and modeling of lithium-ion batteries for future applications
Exploring the Socio-Cultural Dynamics of Nocturnal Urban Landscapes: A Case Study
Get PDFThis dissertation explores nighttime social leisure activities in public parks within urban working- and middle-class communities. As cities confront climate change, shifting work schedules, and post-pandemic lifestyles, neighborhood parks have gained renewed importance after dark, especially in areas where households have limited private space. These non-commercial nighttime uses are often overlooked in planning, design, and built environment studies, yet they play a vital role in fostering cultural identity, social connection, and community well-being.
Focusing on Williamsburg and Bushwick in Brooklyn, New York, this research investigates how public parks are used at night, by whom, and for what purposes. New York City’s 24-hour rhythm and cultural diversity provide a rich context for understanding how communities shape nocturnal public life. Drawing from urban design, cultural geography, and urban sociology, the study examines how nighttime activities reflect the evolution of spatial patterns and social dynamics.
The research employs a mixed-methods approach that includes ethnographic observation, semi-structured interviews, archival review, spatial-temporal mapping, and content analysis. Findings highlight how different user groups, across age, gender, and cultural backgrounds, adapt and reimagine public space after dark, often in ways that resist formal programming and challenge prevailing narratives of safety and surveillance.
By centering grassroots practices, this dissertation advances a more inclusive understanding of urban nocturnality. It calls for planning and design approaches that move beyond control and consumption, embracing the spontaneity, diversity, and relational rhythms that define everyday public life in the nocturnal city
Nature Playscape: Investigating Children’s Play Behavior and Environmental Affordances in a School Playground
Get PDFExisting research demonstrates that the physical environment can either hinder or enhance children’s play behavior. Diverse outdoor settings are especially effective in fostering motivation to play, contributing to children’s physical, social, and cognitive development. In response to the growing belief that outdoor play is both a necessity and a right for young children, particularly amidst concerns about nature deficit disorder and the rise of urban living among children, this study investigates the concept of nature playscapes, or naturalized playgrounds, as a vehicle for reconnecting children with the natural world. While contemporary playground design often struggles to balance structure with creativity, nature playscapes offer unstructured, flexible environments that support child-nature engagement and afford opportunities for self-directed exploration, challenge, and learning. Grounded in the ecological concepts of affordances and behavior settings theory related to children development, this single case study examines how the spatial design of a school nature playscape influences children’s play behavior and environmental affordance use. Focusing on children aged 8 to 11 at Camperdown Academy in Greenville, South Carolina, the research employs a mixed-methods approach including behavioral observation, spatial mapping, and descriptive and inferential statistics.
Findings reveal that manufactured, mixed, and natural zones each afford distinct behavioral and developmental opportunities. While manufactured zones promote rule-bound, high-energy play, natural and mixed environments support a broader range of physical, cognitive, and social behaviors, including imaginative and risk-related play. Affordance richness was highest in the natural zone, where children demonstrated flexible social interactions, exploratory risk-taking, and constructive engagement with diverse environmental elements. Developmental differences were also observed: older children engaged in more varied and creative play, while younger children relied more on structured, rule-based activities. Gendered patterns emerged, with boys engaging more in physical and constructive play, and girls more in socially expressive and communication-driven behaviors. By integrating environmental design with behavior analysis, this study contributes to understanding how diverse play settings support inclusive, developmentally responsive, and nature-based learning experiences. The results inform design and policy strategies for creating outdoor school environments that promote holistic child development, equity, and environmental connection
Application of Artificial Neural Network Algorithms for Irrigation Scheduling
No full textNeural networks have been extensively used in predicting soil water tension for improved irrigation scheduling and management. However, their lack of interpretability constrains their efficacy in grasping the nuanced patterns prevalent in soil water tension time series data. The first goal of this research was to develop interpretable deep neural network models for soil water tension prediction across multiple soil depths (0.15m, 0.3m, 0.46m and 0.6m) and prediction horizons (1h, 6h, and 12h). The Neural Hierarchical Interpolation for Time Series (N-HiTS) and Neural Basis Expansion Analysis Time Series (N-BEATS) models were used in this research. Historical soil water tension data collected at the University of Georgia’s C. M. Stripling Irrigation Research Park (SIRP) and in Blackville, South Carolina, were used to train and test the models. The results were benchmarked with the Long-Short-Term Memory (LSTM) to compare the models with a recurrent soil water tension prediction method. All the algorithms were coupled with a probabilistic multi-quantile loss function to quantify the uncertainty associated with predictions. Analysis suggested that the N-HiTS and N-BEATS models outperformed the LSTM model in the two testbeds by maintaining accuracy over the extended horizons and depths. The prediction uncertainty was more controlled for N-HiTS and N-BEATS, with narrower uncertainty bands across horizons and soil depths, while LSTM exhibited widening intervals, reflecting reduced predictive confidence. We demonstrated how the proposed architecture can be augmented with uncertainty quantification to provide probabilistic soil water tension predictions that are interpretable without considerable loss in accuracy. Accurate and interpretable soil water tension predictions can reduce water use, provide timely irrigation, and increase crop yield.
The second goal of this study was to apply deep reinforcement learning algorithms namely proximal policy optimization (PPO) and deep Q-network (DQN) to generate irrigation schedules of an irrigated field located at the University of Georgia’s C.M SIRP. Results indicated that PPO outperformed DQN by converging faster and maintaining stable rewards across the training steps. Crop water use efficiency also indicated that PPO provided a superior performance, highlighting its potential in optimizing both yield and water use. Experiments on deterministic and probabilistic policy decisions demonstrated that the DRL techniques can efficiently learn strategic policies for irrigation optimization in environments with a discrete or continuous action space
A Convergent Mixed Methods Study of the Social Studies Academy in South Carolina Middle Schools
No full textThere is a global labor shortage in the agricultural industry and middle school is a critical time to get students serious about career decision making. The Studies of Occupations, Culture, and Innovations toward Agricultural Literacy (SOCIAL) Studies Academy is a high impact professional development program in South Carolina that provides experiences and for middle school social studies teachers (N = 12) to become more suited to teach their standards associated with the agricultural sciences with hopes of encouraging more students to pursue agricultural careers. This study was a mixed-methods convergent parallel design that examined 1) Academy Fellows (n = 4) and their students (n = 238). Academy Fellows were provided with an expert-developed lesson plan to teach their students about agriculture and agricultural careers. Students were provided a pre-test and post-test 27-item Likert-type survey to gauge their perceptions on agriculture and agricultural careers before and after the lesson. Paired t-tests were used to analyze changes in perception. The Fellows were interviewed, independently from quantitative data collection, about their experiences in the Academy, student engagement and learning, and the lesson that was taught. Open, axial, and selective coding were used to generate six themes from the qualitative data. Then, a convergent analysis was done between the quantitative results and the qualitative themes. The researcher found that the qualitative and quantitative data agreed that the impacts of the SOCIAL Studies Academy suggest a positive student change in perceptions of agriculture and agricultural careers, which may lead to more participation in the agricultural industry
Item 1: Syllabus: American National Government, 100-200 Level Introductory Course
Get PDFThis course explores American national government, balancing institutional standards with government beyond amendments. The course equips students to understand their roles as citizens. Key components include blended learning, a civic engagement letter project, and coverage of civil liberties, civil rights, public opinion, interest groups, the media, political parties, political campaigns, voting behavior, elections, the presidency, bureaucracy, the US Congress, the judiciary, and public policy. ThThis course explores American national government, balancing institutional standards with government beyond amendments. The course equips students to understand their roles as citizens. Key components include blended learning, a civic engagement letter project, and coverage of civil liberties, civil rights, public opinion, interest groups, the media, political parties, political campaigns, voting behavior, elections, the presidency, bureaucracy, the US Congress, the judiciary, and public policy. This flexible course employs varied instructional methods
Item 1: Introduction - Civic Engagement Stories
Get PDFThis one-page document describes this project. It introduces the idea of using stories, poems and other narrative sources as a way to help both curricular and co-curricular educators help students to think about their civic involvement. It introduces the three themes of the stories: Connecting & Avoiding, Helping, and Teaching in a Civic Context
Item 4: Diverse Conversations - Unify America Challenge Assignment
Get PDFThe purpose of this assignment is to build civic-communication skills through a one-on-one, paired conversation on important societal issues (e.g., economy, health, immigration and more) and written reflection. These are also important topics examined by the social sciences and humanities. To productively work toward civic engagement, it is important to learn to have a civil conversation and dialogue about issues affecting our society with someone who has a different perspective than your own The purpose of the Unify Challenge, run by Unify America, is “to spark conversation with other college students across the country who might be politically and socially different from each other and learn about (be exposed to) varying perspectives.” After the paired conversation, students will write a reflection about their experience