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Adaptive AI-Based Algorithms for Optimizing Communications Across Network Layers of Dynamic Flying Ad Hoc Networks
No full textElectronic Thesis or DissertationDynamic Flying Ad Hoc Networks (FANET) have emerged as a prominent research area due to the innovation, development, and widespread adoption of drone terminal devices. The increasing diversity of FANETs has introduced new demands and challenges for airborne communications, particularly in the lower layers of the Open Systems Interconnection (OSI) communication model. This study begins by clarifying the research context and providing relevant definitions. It then outlines the key challenges and limitations of traditional methods. It is followed by optimizing the FANET communication across three critical dimensions: high transmission data rate communication, decentralized distributed high-sensing communication, and adaptive dynamic high-mobility communication. While Terahertz (THz) links can achieve data transmission rates exceeding 100 Gigabits per Second (Gbps), they are highly susceptible to obstacles and require narrow, highly directional beams to concentrate signal radiation. To address this, this dissertation proposes a comprehensive Terahertz airborne network (TAN) media access control (MAC) protocol that facilitates dynamic FANET networks with resilient, smooth, and high-rate links. Moreover, Directional Antennas (DA), though vital in FANETs, are limited by their inability to exchange messages as frequently as Omnidirectional Antennas (OA) to sense the surrounding environment. To overcome this, this study introduces a Distributed Adaptive Layer (DAL) protocol between the MAC and Physical (PHY) layers. DAL enables each node to interact with the environment only using local observations, avoiding coordinator participation and reducing communication delay while maintaining high throughput. Additionally, the diverse flight speeds and the associated Doppler effect significantly impact FANET performance. To mitigate this, this work implements the Doppler Adaptive Waveform Engine (DAWE) protocol, which adjusts node modulation methods and parameters, responding to the time series highly dynamic environment in FANET. This approach reduces deployment complexity and improves Bit Error Rates (BER). Overall, this dissertation presents multiple protocols for offering a comprehensive framework for optimizing FANET communications, demonstrating the effective applications of advanced computational algorithms to complex, real-world network scenarios, and paving the way for more efficient and reliable deployment of FANETs
Perfect Recovery in Heterogeneous Stochastic Bicluster Models
No full textElectronic Thesis or DissertationUnlike traditional clustering, which groups only objects based on similarity, biclustering simultaneously partitions both objects and features into subgroups, known as biclusters, based on their expression patterns. We model this as the densest k-disjoint-biclique problem, in which a weighted complete bipartite graph is partitioned into k disjoint subgraphs to maximize the sum of their densities. In our first solution approach, we show that underlying bicliques can be recovered with high probability by solving a particular semidefinite relaxation, provided the input graph is drawn from a heterogeneous planted–bicluster model. We proceed to derive necessary and sufficient conditions for exact recovery, then via numerical simulations, we explore the impact of sparsity, weight distributions, block sizes, and outliers on the semidefinite relaxation performance. Our results reveal sharp phase transitions, identifying critical thresholds for perfect recovery of the planted structure. In the noiseless regime, i.e., when all inter-cluster edges carry negligible or zero weight, the semidefinite relaxation is exact whenever the graph contains k large, dense, disjoint bicliques. When noise is present (i.e., nonzero between-cluster weights), we show that significantly smaller biclusters remain recoverable if inter-cluster weights are sufficiently small or sparse. In fact, for approximately sparse graphs where inter-cluster weights vanish as min{m, n} becomes large, we prove recovery of biclusters whose size grows only polylogarithmically in min{m, n}, under mild distributional assumptions. As an alternative to the semidefinite relaxation, we also reformulated the k-disjoint-biclique problem as an orthogonality-constrained optimization problem and apply an extended Bregman-iteration splitting method (after Lai & Osher) to jointly recover object and feature clusters. Extensive experiments confirm the theoretical phase transition boundaries and demonstrate the practical effectiveness of both methods
“Soy Poeta, Mil Por Mil”: a Poetic Autoethnography on Translingual Identity Formation and Negotiation
No full textElectronic Thesis or DissertationThis poetic autoethnography examines the metafunctions of translanguaging as a poetic device and their roles in negotiating my translingual identity as a Cuban American writer and language instructor. Rooted in the theoretical frameworks of translanguaging, this study examines six autobiographical poems (2018–2024) through the textual, ideational, and interpersonal metafunctions of systemic functional linguistics (SFL). By analyzing rhythm, syntax, and lexicogrammatical choices, this research explores how my lived experiences, audience engagement, and self-positioning shape, and are shaped by, my Spanglish poetry, demonstrating how the composition, revision, and presentation of my work serve as iterative acts of self-actualization, linguistic agency, and translingual empowerment. Furthermore, this study explores how the development of a translingual disposition has influenced my pedagogical approach as an English composition and English as a Second Language (ESL) instructor. Recognizing students’ diverse linguistic repertoires, I cultivate a translingual space that validates multilingual voices and fosters translingual identities, positioning language as a dynamic social practice and a source of creative and intellectual strength. This poetic autoethnography therefore presents how the poetic evolution of my translingual disposition served (and continues to serve) as an empowering tool of introspection, cultural reconciliation, and self-actualization across personal and professional practices. Esta autoetnografía poética examina las metafunciones del translenguaje como dispositivo poético y su papel en la negociación de mi identidad translingüística como escritora e instructora de inglés cubanoamericana. Basado en los marcos teóricos del translenguaje, este estudio examina seis poemas autobiográficos (2018-2024) a través de las metafunciones textuales, ideacionales e interpersonales de la lingüística sistémica funcional (LSF). Mediante el análisis del ritmo, la sintaxis y las elecciones lexicogramaticales, esta investigación explora cómo las experiencias vividas, la participación de la audiencia y el autoposicionamiento dan forma a mi poesía en spanglish, demostrando cómo la composición, la revisión y la presentación de mi trabajo sirven como actos iterativos de autorrealización, agencia lingüística y empoderamiento translingüístico. Además, este estudio explora cómo el desarrollo de una disposición translingüística ha influido mi enfoque pedagógico como profesora de composición e inglés como segundo idioma (ESL). Al reconocer los diversos repertorios lingüísticos de los estudiantes, cultivo un espacio translingüe que valida las voces multilingües y fomenta las identidades translingües, posicionando el lenguaje como una práctica social dinámica y una fuente de fuerza creativa e intelectual. Por lo tanto, esta autoetnografía poética presenta cómo la evolución poética de mi disposición translingüística sirvió (y sigue sirviendo) como una herramienta empoderadora de introspección, reconciliación cultural y autorrealización en todas las prácticas personales y profesionales
Electronic Book Acquisition Strategies in Academic Libraries: A Review of the Literature
No full textElectronic book (e-book) acquisition models have evolved over the decades they have been available to library customers. This review leverages findings from scholarly literature to document the proliferation and evolution of e-book acquisitions models, their strengths and weaknesses in various contexts, and their role in the collection development strategies of academic libraries. From firm orders and subscription packages to demand-driven and evidence-based acquisitions, engagement with e-book acquisitions models varies considerably based on factors such as library budget and staffing, institutional curriculum and programs, consortial affiliations, support for textbook affordability initiatives, and COVID-19 responses. The findings from this literature review suggest multiple acquisition models are frequently used in combination; librarians closely monitor e-book expenditures and use, regularly modifying acquisitions parameters; and e-book strategy is dependent on institutional goals, library budgets, consortial participation, and marketplace realities. Additionally, the increased availability of e-books and their acquisitions models have created opportunities for research that compares the efficiency and effectiveness of e-book purchasing models and draws on existing and evolving evaluative models to establish benchmarks for measuring success.author accepted manuscript (AAM
Reconstructing Early Earth and Lunar History: Insights from Terrestrial and Extraterrestrial Zircon
No full textElectronic Thesis or DissertationZircon (ZrSiO4) is a common accessory mineral in terrestrial and extraterrestrial rocks, valued for its ability to record magmatic conditions and serve as a geochronometer. Its resilience to weathering, capacity to incorporate U and Th while excluding Pb during growth, and ability to retain REEs, Hf, and Ti make zircon a powerful tool for probing high-temperature events such as meteor impacts. These properties have provided insights into early Earth’s evolution, from the Hadean era to the emergence of an atmosphere, oceans, felsic crust, plate tectonics, and the ingredients for life. However, Hadean zircon are rare, limiting data and necessitating modern analogs to improve our understanding. This dissertation comprises three parts: 1) geochemical characterization of inclusions in impact-formed zircon, 2) mathematical modeling of the size-frequency-distribution of impactors during the Hadean, and 3) tomographic analysis of Pb nano-spheres in lunar zircon. First, mineral inclusions in zircon from Sudbury, Canada, and Morokweng, South Africa, are compared to possible parent rock compositions. Inclusions trace host rock composition, and trends in Total Alkali Silica and Quartz – Alkali Feldspar – Plagioclase – Feldspathoid diagrams suggest Hadean zircon formed in tonalite-trondhjemite-granodiorite-like rocks. This research reconstructs ancient crustal compositions erased from the geologic record. The second part of this treatise models of high-energy impacts revealing that SiO2 enrichment occurred early in Earth’s history. Geochemical fractionation patterns in Sudbury’s differentiated impact melt sheet suggest impacts contributed to felsic proto-continents, with a Late Heavy Bombardment producing magma with ≥58 wt.% SiO2, covering ca.10% of Earth’s surface to a minimum thickness of approximately 2 km. Lastly, the third part of this dissertation uses the isotopic and trace element composition of extraterrestrial zircon in order to evaluate high temperature impact events. Atom Probe Tomography (APT) lattice reconstructions for Apollo 14 lunar zircon, identify Pb nano-clusters linked to high-energy impacts. The APT reconstruction of a Pb nanocluster within a ~4.3 Ga lunar zircon has a 207Pb/206Pb ratio of 1.39 ±1σ indicating Pb accumulation from 4.3–3.9 Ga, reflecting a major lunar impact event at ~3.9 Ga. This suggests the Moon’s surface experienced a high-energy event, or events, at 3.9 Ga
Expert and Non-Expert Behavioral Patterns and Improvements for Coastal Hazard Adaptations in the Southeastern United States
No full textElectronic Thesis or DissertationEffective mitigation and recovery of water-based hazards is critical to reduce their impact on coastal communities. However, gaps in the existing literature between the scale and temporal scope of hazard mitigation provides room for development in key steps in the processes for household and community mitigation. In this dissertation, I designed four studies to investigate different scales and stages of the coastal hazard mitigation process in four communities along the United States Gulf and Atlantic Coasts. First, I hosted expert stakeholder focus groups to design a conceptual framework for long-term compound flood preparation by coastal municipalities. Second, I utilized a public survey to identify contributing variables to the voluntary household flood insurance purchasing behavior of coastal residents. Third, I conducted a series of experimental studies to determine differing responses by individuals to variations in three hurricane information communication tools. Finally, I utilized a public survey to determine a causal link between household mitigation actions and subsequent recovery from coastal hazard events. The findings of the chapters of this dissertation are collected to better understand and portray important steps in the process of short and long-term coastal hazard adaptation for at-risk communities. The individual and overarching conclusions I identify can provide important support for coastal community planning as well as future research into water-based coastal hazard preparation and recovery
The Weight of the Last Vote: the Imposed Responsibility of the Pivotal Voter in American Juries
No full textElectronic Thesis or DissertationJury decision-making is a cornerstone of the American criminal justice system, yet the role of the pivotal voter—the juror whose vote determines the final outcome—remains understudied. This study examines the interplay between juror personality traits, deliberation dynamics, and the influence of nonconforming opinions on final verdicts. Utilizing a mixed-methods approach, 35 participants engaged in simulated jury deliberations where a confederate juror was strategically positioned to assess conformity effects. Key variables analyzed included openness, agreeableness, collaborative and competing conflict management styles, and civic engagement, measured through pre- and post-deliberation surveys. Findings indicate that collaborative conflict management styles encouraged deliberation while openness, agreeableness, competitiveness, and active civic engagement did not significantly impact the deliberative process. Notably, jurors who initially voted “not guilty” independently adjusted their decisions in group settings to match the group majority opinion of “guilty,” suggesting the profound impact of social influence and conformity pressures. Policy implications highlight the necessity of procedural safeguards to maximize collaboration and appropriately capture group effects during jury deliberations. Recommendations include the adoption of anonymous voting post-deliberation, structured deliberation guidelines to promote equal participation, and enhanced juror education on conformity biases. Additionally, findings support further exploration of jury size effects, individual juror pressures, and online versus in-person deliberation differences. By refining jury procedures to encourage independent decision-making while preserving collaborative discussion, this research contributes to the ongoing discourse on the integrity, fairness, and future of the American jury system
A Corpus-Driven Study of Discourse Communities in Applied Linguistics in Turkiye and the United States
No full textElectronic Thesis or DissertationThis study examines the construction of writer identity through stance markers in applied linguistics theses from the United States and Turkiye, adopting a corpus-driven approach. Drawing on 200 theses (100 from each discourse community), the research reveals how the linguistic features reflect the diverse academic conventions of different district discourse communities. The findings highlight how discourse community members in the U.S favor assertive markers to establish authority, while other discourse community members in Turkiye lean toward hedging to maintain caution. These variations underline the cultural and linguistic norms influencing academic writing and how authors position themselves within discourse communities. By integrating corpus linguistics, metadiscourse, and stance, this thesis contributes to understanding writer identity in multilingual academic contexts, offering pedagogical implications for teaching academic writing across diverse linguistic backgrounds
Relationships and Reciprocity: a Collaborative Approach to Ethnoarchaeology of the Choctaw (Chahta) Homeland
No full textElectronic Thesis or DissertationThe Choctaw Ancestral Homeland is an understudied research area in archaeology with even less work done in collaboration with Indigenous descendant communities (both resident and removed). This project was in collaboration with descendant Choctaw communities to produce a body of research useful to the Choctaw people and contribute to the archaeology of the region. In developing this type of research collaboration, the theme of decolonization and Indigenous ontologies emerged, which adds value to the methods, analysis, and broader impacts of the work itself for both archaeologists and descendant communities. The specific research topics for this project were chosen and vetted with Choctaw communities in various avenues and different scales, resulting in three original research articles exploring theory, material culture, and cuisine as they relate to Choctaw culture, archaeology, and decolonization. The work begins with an introduction to the project, which is followed by an article that explores theories and applications of what it means to conduct "Collaborative" archaeology with descendant communities. Next, the second article focuses on the form and function of white glass trade beads on a Choctaw site in Kemper County, Mississippi. Finally, the third article makes the case for evidence of a Choctaw Cuisine in the archaeological record that has endured through time. In conclusion, a summary will be given to highlight the contributions and broader impacts of this research program to both the discipline of archaeology, my own research questions, and the Choctaw people
User Rights Violations in Social Media Responses to Child Sexual Exploitation: a Qualitative Analysis of Brazilian Court Decisions
No full textElectronic Thesis or DissertationThe rise in social media usage and its growing societal impact has been linked to increasing user and platform vulnerabilities to online crime. To prevent online crime and protect their business and potential victims, social media regulation and content moderation have evolved. This evolution has shaped a governance model in which the social media domain prevails over external governance in digital spaces. The absence of unified regulation over digital space has left room for social media to act as regulators and enforcers of crime control measures. However, while social media attempts to protect users from online victimization, their actions may also result in user rights violations. This study builds on the literature on corporate, digital, and platform governance to develop a better understanding of social media's ability to set rules, enforce policies, and exert control as it relates to their responses to child sexual exploitation and abuse (CSEA) violations. More specifically, it examines how the enforcement of CSEA policies by social media platforms limits user rights and explores the context in which user rights violations are likely to occur. This is achieved through a thematic qualitative analysis of court decisions that scrutinize legal disputes where users challenge social media responses of content removal and account disabling due to alleged violation of social media CSEA policies. The study aims to contribute to the literature on social media governance by examining the extent to which court rulings influence and delimit the regulatory authority of social media platforms, particularly in cases involving potential infringements on consumer fundamental rights. It also aims to contribute to the understanding of digital regulation, focusing on the balance between the prevention of online crimes against children and the protection of user rights