Graduate Student Papers

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  • Water Infrastructure Sustainable Development
    Adesoji, Tolulope (2022-11-15)
    This paper explores the role of water infrastructure in sustainable development, with a specific focus on stormwater management. The paper emphasizes sustainable approaches within the water sector, examining stormwater management techniques that mitigate flooding risks. Central to this discussion is the concept of green infrastructure as an example of a decentralized system. The paper also identifies and measures social and environmental indicators influenced by sustainable water infrastructure development.
  • National Strategy for Road Transportation Electromobility
    Adesoji, Tolulope (2022)
    This paper explores the challenges and opportunities in transitioning from fossil fuel vehicles to electric vehicles in the road transportation sector. This paper focuses on the pivotal role of lithium-ion batteries (LIBs) in electric vehicles (EVs). The study advocates the need for comprehensive strategies, which include national policies, rebates, tax credits, and battery recycling investments to help mitigate environmental impacts, reduce carbon emissions, and stimulate economic growth. The paper also emphasizes the importance of recycling spent batteries while scrutinizing the environmental and social consequences of raw material mining for battery production. The paper also proposed strategies to balance promoting electromobility and addressing potential equity and environmental concerns while offering a holistic perspective on the sustainable evolution of road transportation.
  • Beyond the regulatory radar: knowledge and practices of rural medical practitioners in Bangladesh
    Sujon, Hasnat; Sarker, Mohammad H. R.; Uddin, Aftab; Banu, Shakila; Islam, Mohammod R.; Amin, Md. R.; Hossain, Md. S.; Alahi, Md. F.; Asaduzzaman, Mohammad; Rizvi, Syed J. R.; Islam, Mohammad Z.; Uzzaman, Md. N. (2023-11-30)
    Background: Informal and unregulated rural medical practitioners (RMPs) provide healthcare services to about two-thirds of people in Bangladesh, although their service is assumed to be substandard by qualified providers. As the RMPs are embedded in the local community and provide low-cost services, their practice pattern demands investigation to identify the shortfalls and design effective strategies to ameliorate the service. Methods: We conducted a cross-sectional study in 2015–16 using a convenient sample from all 64 districts of Bangladesh. Personnel practising modern medicine, without any recognized training, or with recognized training but practising outside their defined roles, and without any regulatory oversight were invited to take part in the study. Appropriateness of the diagnosis and the rationality of antibiotic and other drug use were measured as per the Integrated Management of Childhood Illness guideline. Results: We invited 1004 RMPs, of whom 877 consented. Among them, 656 (74.8%) RMPs owned a drugstore, 706 (78.2%) had formal education below higher secondary level, and 844 (96.2%) had informal training outside regulatory oversight during or after induction into the profession. The most common diseases encountered by them were common cold, pneumonia, and diarrhoea. 583 (66.5%) RMPs did not dispense any antibiotic for common cold symptoms. 59 (6.7%) and 64 (7.3%) of them could identify all main symptoms of pneumonia and diarrhoea, respectively. In pneumonia, 28 (3.2%) RMPs dispensed amoxicillin as first-line treatment, 819 (93.4%) dispensed different antibiotics including ceftriaxone, 721 (82.2%) dispensed salbutamol, and 278 (31.7%) dispensed steroid. In diarrhoea, 824 (94.0%) RMPs dispensed antibiotic, 937 (95.4%) dispensed ORS, 709 (80.8%) dispensed antiprotozoal, and 15 (1.7%) refrained from dispensing antibiotic and antiprotozoal together. Conclusions: Inappropriate diagnoses, irrational use of antibiotics and other drugs, and polypharmacy were observed in the practising pattern of RMPs. The government and other stakeholders should acknowledge them as crucial partners in the healthcare sector and consider ways to incorporate them into curative and preventive care.
  • Mapping Out the Core Constructs of Social Justice as Heuristics in Selected Technical Communication Articles Using the 4Rs Model
    Ojedele-Adejumo, Temitope (ACM, 2023-10-26)
    This study analyzes social justice thematic directions in technical communication research using Walton et al.’s 4Rs model to determine the field’s conceptualization of justice.
  • Folkloric Tradition as an Epistemology of Environmental Justice
    Ojedele-Adejumo, Temitope (ACM, 2023-10-26)
    This paper explores the connection of Nigerian folkloric tradition to environmental justice through rhetorical analyses of oral traditions. It aims to establish effective approaches to discussing environmental justice in technical communication, focusing on transnational environmental policies and bottom-up interventions. The paper serves as a representative research approach for exploring other non-western traditions and their connection to environmental issues and justice pursuits.
  • Planning Locomotion Techniques for Virtual Reality Games
    Moore, Cameron; Lages, Wallace (ACM, 2023-10-09)
    Locomotion is a fundamental component in many virtual reality (VR) games. However, few techniques have been designed with game’s demands in mind. In this paper, we propose two locomotion techniques for fast-paced VR games: Repeated Short-Range Teleports and Continuous Movement Pads. We conducted a user study with 27 participants using these techniques against Smooth Locomotion and Teleport in a game-like scenario. We found that Movement Pads can be a suitable alternative for games, with competitive performance on various criteria such as time, damage taken, usability, workload, and user preference. On the other hand, Repeated Short-Range Teleport displayed lower usability and higher mental workload.
  • MEMTIS: Efficient Memory Tiering with Dynamic Page Classification and Page Size Determination
    Lee, Taehyung; Monga, Sumit Kumar; Min, Changwoo; Eom, Young Ik (ACM, 2023-10-23)
    The evergrowing memory demand fueled by datacenter workloads is the driving force behind new memory technology innovations (e.g., NVM, CXL). Tiered memory is a promising solution which harnesses such multiple memory types with varying capacity, latency, and cost characteristics in an effort to reduce server hardware costs while fulfilling memory demand. Prior works on memory tiering make suboptimal (often pathological) page placement decisions because they rely on various heuristics and static thresholds without considering overall memory access distribution. Also, deciding the appropriate page size for an application is difficult as huge pages are not always beneficial as a result of skewed accesses within them. We present Memtis, a tiered memory system that adopts informed decision-making for page placement and page size determination. Memtis leverages access distribution of allocated pages to optimally approximate the hot data set to the fast tier capacity. Moreover, Memtis dynamically determines the page size that allows applications to use huge pages while avoiding their drawbacks by detecting inefficient use of fast tier memory and splintering them if necessary. Our evaluation shows that Memtis outperforms state-of-the-art tiering systems by up to 169.0% and their best by up to 33.6%.
  • GesMessages: Using Mid-air Gestures to Manage Notifications
    Li, Xiang; Chen, Yuzheng; Tang, Xiaohang (ACM, 2023-10-13)
    This paper introduces GesMessages, an innovative mid-air interactive application that uses simple gestures to manage real-time message notifications on laptops and large displays. Leveraging cameras on computers or smart devices, the application offers three distinct gestures: expanding notifications for immediate attention, hiding non-urgent messages, and deleting spam messages. We present the technical setup and system design. Additionally, we explore potential applications in context-awareness systems, contributing to gestural interaction research. Our work fosters a deeper understanding of mid-air interaction’s impact on message management and future interactive systems.
  • Sustaining Green Infrastructure through Community Engagement: A Call to Action
    Adesoji, Tolulope (Virginia Tech, 2023-10-17)
    The policy brief addresses the importance of maintaining green infrastructure systems in cities and municipalities in the United States. It also highlights the benefits of green infrastructure, such as stormwater management and improved quality of life, while emphasizing proper maintenance. The brief offers recommendations for policymakers, including collaborative partnerships, funding availability, community engagement, and effectiveness of green infrastructure, contributing to environmental sustainability and community well-being.
  • Numerical Investigation of Cavitating Jet Flow Field with Different Turbulence Models
    Li, Lidong; Xu, Yan; Ge, Mingming; Wang, Zunce; Li, Sen; Zhang, Jinglong (MDPI, 2023-09-19)
    In numerous industries such as drilling, peening, cleaning, etc., a cavitating jet is adopted. However, it is challenging to simulate the cavitating flow field numerically with accuracy. The flow field of the organ pipe cavitation nozzle is simulated in this research using the RNG kε, DES, and LES turbulence models. The LES model can more accurately predict the periodic shedding of a cavitating cloud, which is basically consistent with the jet morphology captured with a high−speed camera. The flow pattern, cavitating cloud evolution and shedding period of a cavitating jet are analyzed. The findings demonstrate that the LES model produces a cavitating effect inside the nozzle that is superior to those produced by the RNG kε and DES models. The vortex rings in the diffusion section are simulated using the LES model, which accelerates cavitation. The cavitating clouds of the organ pipe nozzle show periodic evolutions, with stages of generation, development, shedding and collapse. The periodic shedding of the cavitating clouds exhibits a similar pattern in the vorticities simulated using the LES model, and the vorticities display the small-scale structures where the cavitating bubbles collapse. This study can provide a reference for the simulation of a cavitating jet and the analysis of the cavitating mechanism.
  • Assessment of Machine Learning Algorithms for Predicting Air Entrainment Rates in a Confined Plunging Liquid Jet Reactor
    Alazmi, Asmaa; Al-Anzi, Bader S. (MDPI, 2023-09-15)
    A confined plunging liquid jet reactor (CPLJR) is an unconventional efficient and feasible aerator, mixer and brine dispenser that operates under many operating conditions. Such operating conditions could be challenging, and hence, utilizing prediction models built on machine learning (ML) approaches could be very helpful in giving reliable tools to manage highly non-linear problems related to experimental hydrodynamics such as CPLJRs. CPLJRs are vital in protecting the environment through preserving and sustaining the quality of water resources. In the current study, the effects of the main parameters on the air entrainment rate, Qa, were investigated experimentally in a confined plunging liquid jet reactor (CPLJR). Various downcomer diameters (Dc), jet lengths (Lj), liquid volumetric flow rates (Qj), nozzle diameters (dn), and jet velocities (Vj) were used to measure the air entrainment rate, Qa. The non-linear relationship between the air entrainment ratio and confined plunging jet reactor parameters suggests that applying unconventional regression algorithms to predict the air entrainment ratio is appropriate. In addition to the experimental work, machine learning (ML) algorithms were applied to the confined plunging jet reactor parameters to determine the parameter that predicts Qa the best. The results obtained from ML showed that K-Nearest Neighbour (KNN) gave the best prediction abilities, the proportion of variance in the Qa that can be explained by the CPLJR parameter was 90%, the root mean square error (RMSE) = 0.069, and the mean absolute error (MAE) = 0.052. Sensitivity analysis was applied to determine the most effective predictor in predicting Qa. The Qj and Vj were the most influential among all the input variables. The sensitivity analysis shows that the lasso algorithm can create an effective air entrainment rate model with just two of the most crucial variables, Qj and Vj. The coefficient of determination (R2) was 82%. The present findings support using machine learning algorithms to accurately forecast the CPLJR system’s experimental results.
  • Sustainable Energy Harvesting Mechanism with Flow-Induced Vibration
    Cheng, Marvin H.; Li, Yuejuan; Camargo, Hugo E.; Bakhoum, Ezzat G. (MDPI, 2023-09-11)
    This study investigates the feasibility of utilizing a flow-induced vibration actuator as a potential energy source using piezoelectric energy harvesting. The focus is on exploring the behavior of piezo films configured as cantilever beams subjected to flow-induced vibration, which can be induced with fluid or wind streams. The primary objective is to maximize the harvested energy from the vibrating structure. This paper develops theoretical models to analyze the resonant frequencies and energy-harvesting potential of the piezo films in the context of flow-induced vibration. Experimental validations are conducted to verify the theoretical predictions. The findings indicate that higher operating frequencies in the second mode offer improved energy harvesting efficiency compared with lower modes. With the strategic adjustment of resonant frequencies using attached masses on individual piezo films, the harvestable energy output of a single film can be significantly increased from less than 1 μW to approximately 18 μW. However, the phase differences among individual piezo films can impact frequency measurements, necessitating careful fine-tuning of the physical conditions of individual components. To optimize energy harvesting, this study emphasizes the importance of implementing efficient charging mechanisms. By identifying suitable environmental vibration sources, the required charging duration for a synthesized energy harvesting array can be reduced by 25% as well. Despite certain challenges, such as phase deviations and turbulence, this study demonstrates the promising potential of flow-induced vibration resonators as sustainable energy sources. This work lays the foundation for further advancements in energy harvesting technology, offering environmentally friendly and renewable energy solutions.
  • In Silico Screening of Inhibitors of the Venezuelan Equine Encephalitis Virus Nonstructural Protein 2 Cysteine Protease
    Hu, Xin; Morazzani, Elaine; Compton, Jaimee R.; Harmon, Moeshia; Soloveva, Veronica; Glass, Pamela J.; Garcia, Andres Dulcey; Marugan, Juan J.; Legler, Patricia M. (MDPI, 2023-07-04)
    The Venezuelan equine encephalitis virus (VEEV) nonstructural protein 2 (nsP2) cysteine protease (EC 3.4.22.B79) is essential for viral replication. High throughput in silico/in vitro screening using a focused set of known cysteine protease inhibitors identified two epoxysuccinyl prodrugs, E64d and CA074 methyl ester (CA074me) and a reversible oxindole inhibitor. Here, we determined the X-ray crystal structure of the CA074-inhibited nsP2 protease and compared it with our E64d-inhibited structure. We found that the two inhibitors occupy different locations in the protease. We designed hybrid inhibitors with improved potency. Virus yield reduction assays confirmed that the viral titer was reduced by >5 logs with CA074me. Cell-based assays showed reductions in viral replication for CHIKV, VEEV, and WEEV, and weaker inhibition of EEEV by the hybrid inhibitors. The most potent was NCGC00488909-01 which had an EC50 of 1.76 µM in VEEV-Trd-infected cells; the second most potent was NCGC00484087 with an EC50 = 7.90 µM. Other compounds from the NCATS libraries such as the H1 antihistamine oxatomide (>5-log reduction), emetine, amsacrine an intercalator (NCGC0015113), MLS003116111-01, NCGC00247785-13, and MLS00699295-01 were found to effectively reduce VEEV viral replication in plaque assays. Kinetic methods demonstrated time-dependent inhibition by the hybrid inhibitors of the protease with NCGC00488909-01 (Ki = 3 µM) and NCGC00484087 (Ki = 5 µM). Rates of inactivation by CA074 in the presence of 6 mM CaCl2, MnCl2, or MgCl2 were measured with varying concentrations of inhibitor, Mg2+ and Mn2+ slightly enhanced inhibitor binding (3 to 6-fold). CA074 inhibited not only the VEEV nsP2 protease but also that of CHIKV and WEEV.
  • Unsupervised Learning-Based WSN Clustering for Efficient Environmental Pollution Monitoring
    Tadros, Catherine Nayer; Shehata, Nader; Mokhtar, Bassem (MDPI, 2023-06-20)
    Wireless Sensor Networks (WSNs) have been adopted in various environmental pollution monitoring applications. As an important environmental field, water quality monitoring is a vital process to ensure the sustainable, important feeding of and as a life-maintaining source for many living creatures. To conduct this process efficiently, the integration of lightweight machine learning technologies can extend its efficacy and accuracy. WSNs often suffer from energy-limited devices and resource-affected operations, thus constraining WSNs’ lifetime and capability. Energy-efficient clustering protocols have been introduced to tackle this challenge. The low-energy adaptive clustering hierarchy (LEACH) protocol is widely used due to its simplicity and ability to manage large datasets and prolong network lifetime. In this paper, we investigate and present a modified LEACH-based clustering algorithm in conjunction with a K-means data clustering approach to enable efficient decision making based on water-quality-monitoring-related operations. This study is operated based on the experimental measurements of lanthanide oxide nanoparticles, selected as cerium oxide nanoparticles (ceria NPs), as an active sensing host for the optical detection of hydrogen peroxide pollutants via a fluorescence quenching mechanism. A mathematical model is proposed for the K-means LEACH-based clustering algorithm for WSNs to analyze the quality monitoring process in water, where various levels of pollutants exist. The simulation results show the efficacy of our modified K-means-based hierarchical data clustering and routing in prolonging network lifetime when operated in static and dynamic contexts.
  • Nano-Chitosan/Eucalyptus Oil/Cellulose Acetate Nanofibers: Manufacturing, Antibacterial and Wound Healing Activities
    Elbhnsawi, Nagwa A.; Elwakil, Bassma H.; Hassanin, Ahmed H.; Shehata, Nader; Elshewemi, Salma Sameh; Hagar, Mohamed; Olama, Zakia A. (MDPI, 2023-06-15)
    Accelerated wound healing in infected skin is still one of the areas where current therapeutic tactics fall short, which highlights the critical necessity for the exploration of new therapeutic approaches. The present study aimed to encapsulate Eucalyptus oil in a nano-drug carrier to enhance its antimicrobial activity. Furthermore, in vitro, and in vivo wound healing studies of the novel nano-chitosan/Eucalyptus oil/cellulose acetate electrospun nanofibers were investigated. Eucalyptus oil showed a potent antimicrobial activity against the tested pathogens and the highest inhibition zone diameter, MIC, and MBC (15.3 mm, 16.0 μg/mL, and 256 μg/mL, respectively) were recorded against Staphylococcus aureus. Data indicated a three-fold increase in the antimicrobial activity of Eucalyptus oil encapsulated chitosan nanoparticle (43 mm inhibition zone diameter against S. aureus). The biosynthesized nanoparticles had a 48.26 nm particle size, 19.0 mV zeta potential, and 0.45 PDI. Electrospinning of nano-chitosan/Eucalyptus oil/cellulose acetate nanofibers was conducted, and the physico-chemical and biological properties revealed that the synthesized nanofibers were homogenous, with a thin diameter (98.0 nm) and a significantly high antimicrobial activity. The in vitro cytotoxic effect in a human normal melanocyte cell line (HFB4) proved an 80% cell viability using 1.5 mg/mL of nano-chitosan/Eucalyptus oil/cellulose acetate nanofibers. In vitro and in vivo wound healing studies revealed that nano-chitosan/Eucalyptus oil/cellulose acetate nanofibers were safe and efficiently enhanced the wound-healing process through enhancing TGF-β, type I and type III collagen production. As a conclusion, the manufactured nano-chitosan/Eucalyptus oil/cellulose acetate nanofiber showed effective potentiality for its use as a wound healing dressing.
  • Para-Methoxybenzylidene Acetal-Protected D-Glucosamine Derivatives as pH-Responsive Gelators and Their Applications for Drug Delivery
    Bietsch, Jonathan; Baker, Logan; Duffney, Anna; Mao, Alice; Foutz, Mary; Ackermann, Cheandri; Wang, Guijun (MDPI, 2023-05-27)
    Carbohydrate-based low molecular weight gelators (LMWGs) are compounds with the capability to self-assemble into complex molecular networks within a solvent, leading to solvent immobilization. This process of gel formation depends on noncovalent interactions, including Van der Waals, hydrogen bonding, and π–π stacking. Due to their potential applications in environmental remediation, drug delivery, and tissue engineering, these molecules have emerged as an important area of research. In particular, various 4,6-O-benzylidene acetal-protected D-glucosamine derivatives have shown promising gelation abilities. In this study, a series of C-2-carbamate derivatives containing a para-methoxy benzylidene acetal functional group were synthesized and characterized. These compounds exhibited good gelation properties in several organic solvents and aqueous mixtures. Upon removal of the acetal functional group under acidic conditions, a number of deprotected free sugar derivatives were also synthesized. Analysis of these free sugar derivatives revealed two compounds were hydrogelators while their precursors did not form hydrogels. For those protected carbamates that are hydrogelators, removal of the 4,6-protection will result in a more water-soluble compound that produces a transition from gel to solution. Given the ability of these compounds to form gels from solution or solution from gels in situ in response to acidic environments, these compounds may have practical applications as stimuli-responsive gelators in an aqueous medium. In turn, one hydrogelator was studied for the encapsulation and release of naproxen and chloroquine. The hydrogel exhibited sustained drug release over a period of several days, with the release of chloroquine being faster at lower pH due to the acid lability of the gelator molecule. The synthesis, characterization, gelation properties, and studies on drug diffusion are discussed.
  • Assessing the Reactionary Response of High School Engineering Teachers Offering a Novel Pre-College Engineering Curriculum: Lessons Learned from the COVID-19 Pandemic
    Griesinger, Tina; Olawale, David; Saqib, Najmus; Reid, Kenneth (MDPI, 2023-04-22)
    The coronavirus (COVID-19) pandemic forced a rapid transition of K-16 education to remote and online learning in the final quarter of the 2019–2020 school year. The disruption was extreme for all teachers in K-12 but particularly for teachers involved in pilot programs, such as the NSF-funded Engineering for Us All (e4usa) project. This paper reports the key findings obtained through systematic data collection from a pilot cohort of high school teachers who adapted a brand-new engineering curriculum during the COVID-19 pandemic, students who experienced the adapted curriculum, and a new cohort of teachers who were tasked with teaching the updated curriculum.
  • Curriculum Design in an Agricultural Education Program in Nigeria: Towards Advancing Career Readiness
    Ajao, H.; Alegbeleye, I.D.; Westfall-Rudd, Donna M. (Advancements in Agricultural Development, Inc., 2022)
    This research explores the effective curriculum design for higher-ed in preparing agricultural education graduates for Nigeria’s labor market. The continuing professional education program planning theory serves as the framework guiding this study. The study involves a phenomenological inquiry into the conscientious meaning experience of the faculty and alumni in an agricultural education department. A purposeful sampling method of 14 participants (four professors and 10 alumni) was used to select participants since the study relied on individuals close to the phenomenon. Data was collected using a standardized open-ended questionnaire and the Department’s handbook. Three themes emerged: The Department's curriculum design/development; Stakeholder’s consultation; and Principles considered while designing the curriculum. Recommendations were made for the Department to continuously review and update the curriculum to reflect the current needs of the industry and students. Lastly, the current study was recommended to be replicated in other main agricultural institutions in Nigeria.
  • Development of Innovative Lateral Resistance Systems Featuring Earthquake-Protective Dampers
    Farzampour, Alireza; Mansouri, Iman; Mortazavi, Seyed Javad; Retzepis, Eleni; Kaloop, Mosbeh R.; Hu, Jong-Wan (MDPI, 2023-03-17)
    Several conventional structural systems require sufficient retrofitting design procedures, improvements, and reconstructions to withstand lateral loads and to decrease the occurrence of damage. High strength capacity and ductility for seismic lateral resisting systems improve the structural vulnerabilities and limit damage concentrations in areas subject to seismic conditions. Several types and shapes of structural systems with appropriate ductility and energy dissipation features are currently established as structural fuses to enhance the general performance of the structures and decrease seismic ramifications. To enhance the energy dissipation performance and concentration of the inelasticity, improving the ductile behavior and limiting the unpredictable accumulation of plastic strains is essential. The conventional eccentrically braced systems are examined and reestablished, and the effects of shear fuses used in high-rise buildings are investigated for prototype buildings by implementing the verified simulations. Next, seismic protective fuse systems with innovative dampers consisting of several butterfly-shaped shear links are established. Ultimately, the design guidelines are established based on the conventional eccentrically braced frames (EBFs), which are redesigned with the use of noble seismic protective fuses, and the hysteretic behavior is obtained and compared accordingly.
  • Numerical Investigation of Natural Convention to a Pseudoplastic Fluid in a Long Channel using a Semi-Implicit Scheme
    Chinyoka, Tiri (MDPI, 2023-03-02)
    We develop and computationally analyze a mathematical model for natural convection to a non-Newtonian fluid in a long and thin channel. The channel is bounded by antisymmetric heated and cooled walls and encloses a non-Newtonian pseudoplastic fluid. The flow and heat transfer characteristics are investigated subject to the prevailing buoyancy forces resulting from the combined natural convection and gravitational effects. An efficient and accurate semi-implicit finite difference algorithm is implemented in time and space to analyse the model equations. In the case when the fluid flow and heat transfer are sustained for a long enough time to allow for steady states to develop, the model equations would reduce to a boundary value problem. Even in such cases, we demonstrate that, by recasting the problem as an initial boundary value problem, our numerical algorithms would still converge in time to the relevant, steady-state solutions of the original boundary value problem. We also demonstrate the dependence of solutions on the embedded parameters at a steady state.