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A Novel Organic-Inorganic Hybrid Polymerization Strategy for Titanium Oxide/Polymer Nanocomposites with Supercapacitive Properties
No full textA titanium oxide/carbon-based nanocomposite was synthesized via a unique organic- inorganic hybrid polymerization process. Radical polymerization of acrylonitrile and condensation polymerization of titanium isopropoxide were balanced in an acid-assisted, one- pot synthesis. The resulting hybrid polymer exhibited intermediary properties of its organic and inorganic components, indicating a successful harmonization of the competing organic and inorganic polymerizations. It is suggested that the acid-protonated nitriles from the organic polymer were the sites for hybrid polymerization with the inorganic polymer. In the proposed mechanism, some of the acetone (medium for the radical organic polymerization) might have undergone acid-catalyzed aldol condensation and water elimination during synthesis. When annealed at 900°C, the hybrid polymer transformed into a polycrystalline graphitic carbon/titanium oxycarbonitride nanocomposite with supercapacitive properties. It demonstrated satisfactory electrochemical performance, and an excellent cycling stability with no loss iΩgood specific capacitance of 55.5 F/g at a current density of 1 A/g, low charge transfer resistance of 0.23 capacitance even after 10,000 cycles. A fabricated symmetric device showed fair performance with a low charge-transfer resistance of 0.44 Ω, specific capacitance of 25.5 F/g at 1 mV/s, energy density of 1Wh/kg, and power density of 900 W/kg, highlighting its potential for energy storage applications.https://digital.library.ncat.edu/gradresearchsymposium25/1100/thumbnail.jp
Computer Vision-based Firebrand Analysis: Dimensional Computation, Trajectory Prediction and Mass Estimation
No full textFires harnessed effectively have been a cornerstone of human advancement, yet their uncontrolled manifestations pose significant risks to lives, both natural and human-made environments, and the continuity of business. The incidence of wildland fires, wildland-urban interface (WUI) fires, and open urban fires represent some of the most challenging adversities faced by modern societies. Their catastrophic nature contributes significantly to the environment and has an impact on biodiversity, including both flora and fauna. Citing the studies that focused on investigating civilian fatalities from wildfires and studying their behaviors and the data from the Attorney Generals Department (AGD) bushfire life loss dataset, there were around 441 fatalities from four wildfires alone, the 2009 Victorian Bushfire, 2017 Portugal Forest Fire, 2018 Camp Fire California, and 2023 Maui Hawai wildfire. Out of which 27.67 % of deaths were in the United States alone. Citing the Nationwide data compiled by the National Interagency Coordination Center (NICC), the magnitude of fire-related incidents in the United States alone, with over 70,025 wildfires since 2000, have burned almost 7.0 million acres causing thousands of civilian casualties and injuries. The total cost incurred in damages from the costliest wildfires from the year 2000 to 2020 in the United States alone is $51.18 billion. Statistics like these underscore the urgent need for adequate fire management strategies forhttps://digital.library.ncat.edu/gradresearchsymposium25/1106/thumbnail.jp
Evaluating Trojan Attack Vulnerabilities in Autonomous Landing Systems for Urban Air Mobility
No full textThis study examines vulnerabilities in the autonomous landing systems of Urban Air Mobility (UAM) vehicles, with a particular focus on Trojan attacks targeting Convolutional Neural Networks (CNNs) used for navigation. Trojan attacks introduce covert triggers into CNN models, leading to misclassifications under specific conditions while maintaining normal functionality in typical scenarios. Our research specifically investigates the susceptibility of Autonomous Aerial Vehicles (AAVs) employing the widely adopted DroNet model for real-time obstacle avoidance. To assess these vulnerabilities, we curated a custom dataset consisting of over 5,000 images of landing pads, categorized under both normal and Trojan-triggered conditions. Our analysis revealed a significant drop in model accuracy— from 96.4% under clean data conditions to 73.3% when Trojan triggers were present. This substantial decline highlights the severe impact of Trojan attacks, particularly during critical landing operations. These findings emphasize the urgent need for robust defense mechanisms to mitigate Trojan-induced threats within UAM systems, which play a crucial role in navigation, obstacle avoidance, and secure communication with ground control. As UAM technologies become increasingly integral to transportation and emergency response frameworks, ensuring their cybersecurity is imperative to protecting both lives and infrastructure.https://digital.library.ncat.edu/gradresearchsymposium25/1108/thumbnail.jp
Biomimetics of Pro-angiogenic Endothelial Dysregulations Enabled by Segregated Tumor Endothelial Co-culture for On-chip Drug Testing
No full textTumor Endothelial Co-culture for On-chip Drug Testing Reem Ali, Simrit Safarulla, Vikram Surendran, Arvind Chandrasekaran CBBE, COE, NCA&T Tumor angiogenesis plays a crucial role in cancer progression. The tumor vasculature interface exhibits aggressive disruption of the endothelial lining of blood vessels, mediated by the release of pro-angiogenic factors, by the tumor. Endothelial disruption allows the blood vessels to become permeable, enabling angiogenesis towards the tumor and ultimately, circulation of tumor cells into the bloodstream. Angiogenic sprouting is characterized by disruption of the endothelial adherens junction, adoption of tip-cell phenotype, and sprouting. Our previous work has successfully shown endothelial disruption by tumor stimulation through an On-Chip culture. Given the nature of that particular culture, angiogenic sprouting is difficult to image due to the orientation of cells. We have developed a new segregated co- culture platform that enables the examination of individual cell populations through an on- demand ECM introduction. When segregating the cell types, and not giving them a medium to migrate within, we impede chemotaxis while still allowing for interaction. This allows for the facilitation of cell dynamics and enables observation of cell responses based solely on signaling. Endothelial disruption occurs without the ECM, but the effect on sprouting is unknown. We seek to understand the mechanism behind angiogenic dynamics and explore the role of the ECM in angiogenic sprouting.https://digital.library.ncat.edu/gradresearchsymposium25/1118/thumbnail.jp
Turbine Based Combine Cycle Exoskeleton Engine Architecture (TBCC ESE)
No full textThe concept of combined cycle jet engines is not new. It represents the idea of having an aircraft travelling from ground speed to the high Mach numbers using a single propulsion system that can navigate the various flow realms. Combined cycle jet engines can fall into two broad categories, rocket based combined cycle engines (RBCC) and turbine based combined cycle (TBCC) engines. This research effort presents an innovative approach to the design of a TBCC engine. In a move away from the design of traditional jet engines where all of the rotating turbomachinery are mounted on a central rotating shaft; the TBCC ESE architecture has all of its rotating turbomachinery mounted on rotating drums. This approach presents a jet engine architecture with a hollow central core, in which the high-speed engine can be designed.https://digital.library.ncat.edu/gradresearchsymposium25/1125/thumbnail.jp
Enhanced Heat Transfer in Rayleigh-Bénard Convection via Hexagonal Honeycomb Prism Mixer: A Numerical Study
No full textRayleigh-Benard convection, which consists of a scenario where fluid is heated from below, is of great importance in industrial applications such as food processing and nuclear plant operations. In this study, we propose a passive method of heat transfer enhancement in a rectangular Rayleigh-Benard convection cell by inserting a hexagonal honeycomb prism mixer. This mixer is to be used to protect the coherent structures (thermal plumes) that arise from the heated bottom wall so that they can reach the top cold wall without energy dissipation, thereby enhancing heat transfer. First, the model is verified against an experiment with an aspect ratio of 1.72, and the results of Nusselt vs Rayleigh Numbers were observed to be within 3% of each other. We then proceeded to compare the Nusselt number ratios (Nu/Nu0) of various prism heights and it was found that the height of 0.8H, where H is the height of the cell, yielded the greatest heat transfer ratio (1.11). An enhancement was recognized in several cases and the research seeks to study the effect of different Prandtl numbers in order to develop a heat transfer correlation of the form Nu=f(Ra,Pr).https://digital.library.ncat.edu/gradresearchsymposium25/1128/thumbnail.jp
Bridging Physical Activity Gaps in Low-Income Older Adults for Healthy Aging in place (Based on Tentative Findings)
No full textOlder adults\u27 engagement in physical activity supports health, delays functional decline, and promotes independent living (aging in place). This qualitative study explored the experiences of low-income older adults in maintaining physical function and independence, examining their physical activity habits, barriers, and motivations. In-home interviews were conducted with 20 low-income older adults (M = 75 years) in North Carolina. Thematic analysis of transcribed interviews and notes revealed key patterns. Among participants, 16 engaged in regular physical activity, with walking as the most common form. 12 utilized health clubs or wellness programs, citing social connections and accessibility as motivators. However, health concerns, time constraints, transportation, safety, and lack of motivation were major barriers. While 13 participants had exercise equipment at home, only seven used it consistently. Positive experiences, such as social engagement at fitness centers, feeling energized, and maintaining health, motivated participation. Findings highlight inconsistencies in physical activity among low-income older adults. Addressing barriers such as health limitations and transportation, while providing affordable, accessible wellness programs and virtual fitness options can improve participation. Enhancing community support can help older adults sustain physical activity, promoting their ability to age in place healthily. Ongoing Research: Preliminary resultshttps://digital.library.ncat.edu/gradresearchsymposium25/1146/thumbnail.jp
Applying Cognitive Load Analysis and Physiological Signal Integration to Operator Safety in Human Robot Collaboration
No full textAs cyber-physical systems continue to proliferate in Industry 4.0, ensuring operator safety in human-robot collaboration (HRC) has become increasingly critical. Collaborative industrial settings demand a thorough understanding of how operators and robots interact under varying cognitive demands. This study explores the dynamic relationships among EEG, GSR, and ECG signals during collaborative robotics tasks using a robust multimodal approach. By employing analytical techniques such as phase space plots, canonical correlation analysis (CCA), time series analysis and mini-batch K-Means clustering, the research reveals insights into workload transitions and cognitive stress in a typical industrial setting. These findings underscore the importance of integrating physiological signals to provide a comprehensive view of operator responses, enabling the development of adaptive systems that enhance safety and efficiency in real time within HRC environmentshttps://digital.library.ncat.edu/gradresearchsymposium25/1156/thumbnail.jp
Liver Cell Culture on ITO-SAMs and Metabolite Analysis using NMR for Drug Toxicity Applications
No full textDespite the emergence of three-dimensional (3D) cell culture systems, two dimensional (2D) cultures remain prevalent due to their cost-effectiveness, reproducibility, and ease of analysis. This study aims to develop a novel self-assembled monolayer (SAM)-based cell culture platform for growth of hepatocytes and to explore advanced metabolomic analysis techniques for enhanced understanding of hepatotoxicity. Indium-Tin Oxide (ITO) functionalized with 3-aminopropyl (triethoxysilane) (APTES) is hypothesized to serve as an optimal scaffold for drug toxicity screening and as a model for Micro Engineered Organs (MOE). Surface characterization was performed using Atomic Force Microscopy (AFM) and X-ray Photoelectron Spectroscopy (XPS). HepG2 liver cells were cultured on ITO modified with APTES. Cell proliferation and cytotoxicity were assessed using MTT and Live/Dead assays. The scaffold of ITO modified with APTES provides an optimal SAM surface for HepG2 cell adhesion and proliferation as evidenced by confocal microscopy images. Preliminary metabolomic analysis through Nuclear Magnetic Resonance (NMR) spectroscopy offers detailed insights into intracellular responses and metabolites normally undetectable by regular CMP (comprehensive metabolomic pathway) tests. This study lays the groundwork for the development of more physiologically relevant in vitro hepatocyte models, potentially enhancing the accuracy of drug toxicity screening.https://digital.library.ncat.edu/gradresearchsymposium25/1175/thumbnail.jp
Engineering Synthetic Beneficial Biofilms: A Comprehensive Framework for Diagnostic and Therapeutic Applications
No full textBiofilms, microbial communities adhering to surfaces, account for 70% of human microbial diseases. While their harmful effects are well-studied, growing interest in beneficial biofilms spans applications from biological control to industrial corrosion prevention. However, their complexity challenges the development of a systematic engineering framework to harness their potential. Synthetic Beneficial Biofilms (SBBs) offer a novel approach for various applications, particularly in healthcare. These engineered microbial communities can mimic harmful biofilms for treatment studies or be synthesized for cell therapeutics and drug delivery, aiding in diagnosing and treating gut microbiome diseases. We present an innovative interdisciplinary framework combining mechanical and bioengineering principles to control programmable biofilm production. This approach identifies crucial steps from selecting interaction surfaces to designing bacterial communities and ensuring their functionality. It outlines key phases of biofilm formation preformation, formation, and post- formation each with specific target genes and modulation criteria. Emerging technologies are integral to this framework, including nextgeneration transcriptomics, 3D bioprinting, light- controlled genetic devices, and non-invasive real-time monitoring. This comprehensive framework can unlock the full potential of SBBs, from diagnostic to therapeutic approaches.https://digital.library.ncat.edu/gradresearchsymposium25/1181/thumbnail.jp