Engineering Commons^™

A Coupled Source Panel, Actuator Line, And Viscous Vortex Particle Method In An O(N) Scheme, Ryan Anderson, Andrew Ning

Faculty Publications

Wake interactions play a significant role in aerodynamics. However, common modeling approaches are either expensive or lack fidelity, making them unreliable or difficult to use in the design process. The vortex particle method can capture the relevant physics effectively, but imposing boundary conditions with solid surfaces in a computationally efficient way is challenging. We explore two possible methods of imposing solid surface boundary conditions of vortex particle simulations. The first, a novel variation on a pure particle approach, is easy to implement but is moderately expensive, and suffers from some numerical instability. The second, source panels accelerated with a fast …

Isogeometric Boundary-Conforming Body-In-White Crash Model Construction, Analysis, And Comparison With Fem Model, Kendrick M. Shepherd

Faculty Publications

In this paper, we discuss model generation to rebuild the body-in-white of a 1996 Dodge Neon finite element model into a isogeometric conforming analysis-suitable crash model. We then perform the first known boundary-fit isogeometric body-in-white crash analysis of the vehicle and compare results achieved by traditional finite element methods. Results indicate the value and potential of high-order meshes in analysis.

The Rayleigh Problem (Random Flights) Is Everywhere Redux, John E. Gray, Stephen R. Addison

Journal of the Arkansas Academy of Science

The phase noise problem (or Rayleigh problem) occurs in all aspects of radar. It is an effect that a radar engineer or physicist always has to take into account as part of a design or in an attempt to characterize the physics of a problem such as reverberation. Normally, the mathematical difficulties of phase noise characterization are avoided by assuming the phase noise probability distribution function (PDF) is uniformly distributed, and the Central Limit Theorem (CLT) is invoked to argue that the superposition of relatively few random components obey the CLT and hence the superposition can be treated as a …

Inverting Kite Structure & Stability For Airborne Wind Energy, Joshua Vandervelde , '23

Senior Theses, Projects, and Awards

Airborne Wind Energy (AWE) is an emerging method of extracting clean energy from high altitude airstreams with tethered kites, but inflated kites presently lack actuators to control lift and roll. Inverting wings show promise at providing both forms of maneuverability and have so far been researched to validate lift vector manipulation. This capstone project aims to demonstrate the applicability of inverting wings to roll control by segmenting an inflated wing into sections with independent inversion control, inducing a roll moment. The preliminary results from this novel wing design suggest that double inversion does indeed facilitate roll control, but further roll …

Conceptual Architecture For Digital Twin Implementation In A Smart City Framework, Wesley Conwell

All ETDs from UAB

More than 9 billion people are expected to live on the planet in 2050, about two-thirds in cities. This substantial population growth in urban areas increases demands on cities' resources, services, and infrastructure. Hence, many cities leverage intelligent technologies to ensure urban communities' efficiency in integrating massive infrastructure components and services. Cities define this reconstruction of their operational framework as a smart city. Effective resource consumption management in a smart city integrative structure presents a problem with solutions concerning the distribution of city services. This dissertation aims to establish a conceptual framework to effectively manage resource consumption in a smart …

New Heat Exchanger Modeling In The Passive Heat Removal System Of Vver-1200 Nuclear Power Plants, Bugrahan Mangan

All ETDs from UAB

The current work introduces an innovative methodology for modeling heat exchangers inside the passive heat removal system (PHRS) of water-water energetic reactor (VVER) nuclear power facilities. PHRS serves a crucial role in ensuring the secure and effective dissipation of residual heat produced during the shutdown of a reactor. Nevertheless, the current heat exchanger models exhibit deficiencies in terms of their thorough depiction of the geometric structure and thermal properties, hence limiting their precision and suitability for various applications.This study introduces a novel approach to modeling heat exchangers, with a specific emphasis on accurately representing complex geometric characteristics and including thermodynamic …

Development And Evaluation Of A Nanomatrix Coated Stent Using A Vascular Sheet With Atherosclerosis Model, Xixi Zhang

All ETDs from UAB

While cardiovascular stent technology has considerable advances, there are hurdles to overcome due to the dysfunctional stented arteries which fail to maintain vascular homeostasis. Current stent designs ignored the significance of promoting functional artery healing (pro-healing). Therefore, we developed a pro-healing nanomatrix coating for stent. Previous studies investigated its effect on individual vascular cell type. In natural artery, there are multiple vascular cell types that strongly affect stent performance. Thus, an in vitro vascular double-layer (VDL) system was used to observe stent effects on different vascular cell types. And the pro-healing ability and mechanism of the nanomatrix coated stent were …

Impacts Of Transportation Network Companies On Urban Congestion In A Medium-Sized City, Furat Shakir Salman

All ETDs from UAB

The rise of ride-hailing and on-demand transportation services offered by Transportation Network Companies (TNCs) (such as Uber and Lyft) has been one of the key factors contributing to the growth of shared mobility services in recent years. The presence of contradictory findings on the impacts of TNCs necessitates the undertaking of an investigation into the shifts in mode choice that occur in the context of TNC services and their impacts on urban congestion. As a result of difficulties in gathering TNCs field data, it is still not possible to fully assess the impact of these services on urban congestion. Moreover, …

Investigation Of Fish Gelatin/Polycaprolactone Nanofibrous Materials Alternating Field Electrospinning Fabrication And Characterization, Hannah A. Lacy

All ETDs from UAB

As human needs and purposes continue to evolve, it has become crucial that the materials with which we address these new applications and challenges evolve in stride. Specifically, the medical field’s need for advanced materials has led to the drive for biomaterial synthesis and processing methods which produce adaptable material characteristics to satisfy application specific needs. Research response has been to expand viable natural/ synthetic biomaterial resources, design innovative nanofiber fabrication techniques with high levels of productivity, ease of access, and cost efficiency, and explore crosslinking and surface treatments/modifications to enhance material characteristics for improved performance. This research employs select …

A Cold Plasma-Enabled Reduction Process For The Fabrication Of Metallic Nanostructures Onto Polymeric Biomaterials, Gerardo Hernández Moreno

All ETDs from UAB

The design and manufacture of novel materials has served as the bedrock for tissue engineering and regenerative medicine. There exists a need for more biocompatible implantable materials in the biomedical device space. The approach to developing biomaterials fit for biomedical devices has been focused on decreasing overall physiological interaction with the local environment. However, the development of more biomechanically favorable materials has placed an emphasis on designing materials that display biomimetic and biomechanical properties resembling that of the host tissue at the implant site. As biomaterials engineering has progressed, the race to find materials that interact at the nano- and …

Quantifying Geogrid Reinforcement Mechanism In Roadway Performance Using Cyclic Plate Load (Cpl) Test, G.S. Ellithy, A. Crippa

Publications

For decades, geogrids have been used successfully to improve performance in both paved and unpaved roadway construction. Even though the current state of practice differentiates between the design methodology incorporating geogrids in paved and unpaved roadways, the true improvement contribution of geogrids is to the base layer, or to the layer that is placed directly on top of it. It has been established that the three reinforcement mechanisms by which geogrids enhance roadway performance are: lateral restraint, bearing capacity increase and membrane tension support. In order to quantify these mechanisms and their contribution to the roadway performance improvement, two Cyclic …

Inkjet-Printed Reseroir Computing Network For In Situ Sensor Predictions, Steven D. Gardner

All ETDs from UAB

The technological achievements made with silicon-based transistors have led to nearly all the computing seen today, complete with benefits such as maximized operating speeds, parallel/tensor processing, minimized power overhead, etc. The silicon electronics industry is foundational to scientific progression with its profound impact on modeling, simulations, and fast/reliable computing. However, silicon-based transistors have evolved to meet their physical limitations and have saturated fields of innovation. New fields in computing outside of silicon-based methods have emerged as exotic materials enter the research domain. The suite of super-performing materials like Graphene, Carbon Nanotubes, and Molybdenum Disulfide have chaotic, non-linear behaviors that make …

Shared E-Scooters And E-Bikesl Analysis Of Trip Characteristics And Usage Patterns In Birmingham, Alabama, Mithila Hasan

All ETDs from UAB

The topic of shared micromobility has gained significant attention in the field of transportation engineering, exhibiting a significant rise in prominence in recent times. Micromobility’s inherent attributes of user-friendliness, ubiquitous accessibility, convenience, and cost-effectiveness have drawn considerable attention from individuals. In addition, the eco-friendly attributes of diverse shared micromobility modes encourage individuals to adopt them for short commutes. VEO emerged in Birmingham, Alabama in 2021 as a new participant in the dynamic landscape of shared micromobility, offering shared e-scooters and e-bikes. Similar to other medium-sized cities, the VEO pilot program in Birmingham captured the attention and participation of local travelers., …

Least Flycatchers Under-Reported In Fall Migration In Arkansas —A Citizen Science Conundrum, L. Barnes, R. Kannan

Journal of the Arkansas Academy of Science

The Least Flycatcher Empidonax minimus is a small passerine migrant bird that passes through Arkansas in fall and spring migration. The birds are vocal during spring passage but relatively quiet and unobtrusive during fall migration, leading to many fewer reports by birdwatchers in fall than spring. We use eBird maps and data to present evidence to support this discrepancy between fall and spring observations. We also show that the species is under-reported in Arkansas during the fall compared to neighboring regions. This may be in part due to the reluctance of some birders to provide the minimal evidence required to …

Citizen Science: Role Of Inaturalist In Biodiversity Documentation And Education In Arkansas, K. Baker, L. Barnes, S. Rana, J. Jackson, R. Kannan

Journal of the Arkansas Academy of Science

iNaturalist is a global online digital platform for documenting and fostering interest in biodiversity, with Research Grade (RG) entries being vetted and scientifically valid observations. Here we present a review of the role of approximately 16,000 Arkansans using the iNaturalist tool for recording 445,000 verifiable observations comprising 10,800 species, with 40 percent RG, and one third of observations still pending confirmation. Overall, plants lead in RG observations followed by invertebrates and birds. Within these groups, reptiles lead in proportion of RG observations, followed by birds and amphibians. Less charismatic or infrequently encountered organisms are less represented. Arkansas ranks about average …

High Signal-To-Noise Ratio Event-Driven Mems Motion Sensing, Mohammad Mousavi, Mohammad Alzgool, Benyamin Davaji, Shahrzad Towfighian

Mechanical Engineering Faculty Scholarship

Two solutions for improving MEMS triboelectric vibration sensors performance in contact-separation mode are reported experimen- tally and analytically. Triboelectric sensors have mostly been studied in the mesoscale. The gap variation between the electrodes induces a potential difference that represents the external vibration. Miniaturizing the device limits the sensor output because of the limited gap. This work offers a warped MEMS diaphragm constrained on its edges. The dome-shaped structure provides one order of magnitude larger displacement after contact-separation than standard designs resulting in one order of magnitude greater volt- age and signal-to-noise-ratio. Secondly, micro triboelectric sensors do not operate unless the …

Development Of Polymeric Sorbents As Reusable Filtration Systems For Remediation Of Pfas Contaminated Water, E. Molly Frazar

Theses and Dissertations--Chemical and Materials Engineering

Decades of use of per- and polyfluoroalkyl substances (PFAS) in a multitude of consumer and industry-based products have led to a devastating amount of soil and water contamination. Although these chemicals and compounds possess advantageous qualities – such as that of PFAS in the role of fire-fighting foams that have no doubt saved countless lives and homes, we must take responsibility for the anthropogenic hazards that threaten our global health. This entails being able to cost-effectively remediate problems created in the past from overuse of toxic substances that could negatively impact our future, and in this case, the future of …

Mechanical And Adhesive Properties Of Supramolecular, Mussel-Inspired Hydrogels, Daniel Darby

Theses and Dissertations--Chemical and Materials Engineering

The exceptional mechanical and adhesive properties of mussel byssal threads come from supramolecular interactions of ligands found in the proteins comprising them. Ligands can form hydrophobic interactions, π-π stacking interactions, and hydrogen bonds, but the strongest supramolecular interaction they demonstrate is metal-ligand coordination. Specifically, Histidine (His-) and nitrodopamine (nDOPA) ligands coordinate to metals in a bidentate fashion and take on tris-, bis-, and mono- modalities (3, 2, or 1 ligand per ion, respectively). The distribution of these modalities is controlled by equilibrium thermodynamics. These same ligands can be used as crosslinks in supramolecular hydrogel networks. Supramolecular hydrogel networks are dissipative, …

Application Of Multi-Scale Computational Techniques To Complex Materials Systems, Mujan N. Seif

Theses and Dissertations--Chemical and Materials Engineering

The applications of computational materials science are ever-increasing, connecting fields far beyond traditional subfields in materials science. This dissertation demonstrates the broad scope of multi-scale computational techniques by investigating multiple unrelated complex material systems, namely scandate thermionic cathodes and the metallic foam component of micrometeoroid and orbital debris (MMOD) shielding. Sc-containing "scandate" cathodes have been widely reported to exhibit superior properties compared to previous thermionic cathodes; however, knowledge of their precise operating mechanism remains elusive. Here, quantum mechanical calculations were utilized to map the phase space of stable, highly-faceted and chemically-complex W nanoparticles, accounting for both finite temperature and chemical …

Surface Properties, Work Function, And Thermionic Electron Emission Characterization Of Materials For Next-Generation Dispenser Cathodes, Antonio Mantica

Theses and Dissertations--Chemical and Materials Engineering

A dispenser cathode’s ability to thermionically emit electrons is highly dependent on its material properties, especially those of the surface. Understanding the relationship between surface properties and electron emission, therefore, is vital to reach the next generation of the many vacuum electron devices (VEDs) that rely on the physics of electron emission. In the past century, many techniques have been developed to characterize material surfaces and quantify thermionic emission. These techniques are based on a wide range of different physical phenomena, including measuring photoemission via the photoelectric effect, measuring the electrostatic potential between metals in electrical contact, and current collection …

Molecular Understanding Of Zwitterions And Quantum Computing For Sustainability, Manh Tien Nguyen

Theses and Dissertations--Chemical and Materials Engineering

The sustainable development of society needs sustainable energy solutions and the mitigation of greenhouse gas emissions. One key subject in this area is the development of safe and efficient ion-based batteries. Moreover, CO₂ capture is a crucial pathway in mitigating emissions from the combustion of fossil fuels. Ongoing efforts are to improve both technologies' safety and efficiency. This thesis presents our efforts to conduct computational research on understanding advanced zwitterionic electrolytes and CO₂ capture. Chapters 2-4 illustrate the computational research to understand ionic solvation in zwitterionic electrolytes. Solid-state electrolytes are essential for safer batteries. While solid polymer electrolytes …

Developing And Modeling Tunable Nanofiltration And Functionalized Membranes For The Separation Of Organics And Inorganics From Water: Per- And Polyfluoroalkyl Substances, Lanthanides, And More, Francisco Cecil Leniz-Pizarro

Theses and Dissertations--Chemical and Materials Engineering

In a world where clean water predictability is challenged by both global warming and the contamination of our natural resources, it is our responsibility to advance water separation technologies into more efficient processes and to lessen their environmental footprint. Pore and surface functionalization of membranes can enhance the separation of ions from water and even help overcome intrinsic challenges that some current separation technologies possess. If we begin with a complete fundamental understanding of the nanoscale interactions that occur in the process of separating ions from water, then we can engineer new functionalized composite membranes to provide alternative processes keeping …

Solid-State Electrolytes For Long Duration Molten Sodium Batteries, Ryan C. Hill

Theses and Dissertations--Chemical and Materials Engineering

Rechargeable batteries have become a staple of modern society, driving the development and expansion of portable electronics and electric vehicles. The long lifetime and high energy density provided by batteries have made them excellent candidates for use in the emerging field of long duration, grid-scale energy storage. However, traditional battery chemistries, such as Li-ion, are not an ideal solution for grid-scale storage, due to high-cost raw materials that are often sourced from volatile markets. Sodium-based batteries are a promising alternative for long duration storage, owing to the domestic abundance of raw materials and energy densities that nearly rival that of …

Leveraging Cell-Substrate Adhesion And Cell Migratory Properties In Skeletal Muscle Constructs And Cancer Metastasis Assays, Lauren E. Mehanna

Theses and Dissertations--Chemical and Materials Engineering

Volumetric muscle loss (VML) remains one of the few skeletal muscle injuries without a reliable and repeatable treatment. In large volume muscle injuries, muscle fibers as well as the surrounding connective tissue are damaged, preventing therapeutic muscle stem cells, called myogenic progenitor cells (MPCs), from reaching the injury site and initiating repair. There is a clinical need to rapidly fabricate in vitro muscle tissue constructs that mimic the native tissue organization, with aligned myotubes, for insertion and integration at the patient’s injury site. In this dissertation, we utilize the MPC’s natural propensity to close gaps across an injury site to …

Identification Of Proteins Involved In Cell Membrane Permeabilization By Nanosecond Electric Pulses (Nsep), Giedre Silkuniene, Uma Mangalanathan, Alessandra Rossi, Peter A. Mollica, Andrei G. Pakhomov, Olga N. Pakhomova

Bioelectrics Publications

The study was aimed at identifying endogenous proteins which assist or impede the permeabilized state in the cell membrane disrupted by nsEP (20 or 40 pulses, 300 ns width, 7 kV/cm). We employed a LentiArray CRISPR library to generate knockouts (KOs) of 316 genes encoding for membrane proteins in U937 human monocytes stably expressing Cas9 nuclease. The extent of membrane permeabilization by nsEP was measured by the uptake of Yo-Pro-1 (YP) dye and compared to sham-exposed KOs and control cells transduced with a non-targeting (scrambled) gRNA. Only two KOs, for SCNN1A and CLCA1 genes, showed a statistically significant reduction in …

Optimal Spacecraft Guidance, Matthew W. Harris, M. Benjamin Rose

Mechanical and Aerospace Engineering Faculty Publications

This book is designed for a one-semester course at Utah State University titled MAE 6570 Optimal Spacecraft Guidance. The class meets for 75 minutes, twice per week, for 14 weeks. There are no prerequisites other than graduate standing in engineering. Proficiency in calculus, differential equations, linear algebra, and computer programming is required. Students find that previous experience in space dynamics, linear multivariable control, or optimal control is helpful.

The goal of the book and course is for students to develop fundamental skills needed to do professional work in the area of spacecraft guidance. After working through the book, students should …

Investigating Collaborative Explainable Ai (Cxai)/Social Forum As An Explainable Ai (Xai) Method In Autonomous Driving (Ad), Tauseef Ibne Mamun

Dissertations, Master's Theses and Master's Reports

Explainable AI (XAI) systems primarily focus on algorithms, integrating additional information into AI decisions and classifications to enhance user or developer comprehension of the system's behavior. These systems often incorporate untested concepts of explainability, lacking grounding in the cognitive and educational psychology literature (S. T. Mueller et al., 2021). Consequently, their effectiveness may be limited, as they may address problems that real users don't encounter or provide information that users do not seek.

In contrast, an alternative approach called Collaborative XAI (CXAI), as proposed by S. Mueller et al (2021), emphasizes generating explanations without relying solely on algorithms. CXAI centers …

Biom 4760: Biomedical Engineering Design Principles (Syllabus), Carl D. Herickhoff

Biomedical Engineering Syllabi Archive

Course Description: Practical design methods emphasizing the front-end or concept development stage of engineering design; design a system, component, or process to meet desired needs within realistic constraints with functioning on multi-disciplinary teams.

Biom 3110(Honors): Medical Physiology (Syllabus), Bradford D. Pendley

Biomedical Engineering Syllabi Archive

Course Description: Basic principles of human physiology and how these are applied in medicine and biomedical engineering problem and devices; physiological principles using appropriate mathematical and engineering models to construct an understanding of how the body works as an integrated system.

Biom 1720: Introduction To Biomedical Engineering Tools (Syllabus), Stephen Strain

Biomedical Engineering Syllabi Archive

Course Description: Use of computer tools for data analysis, presentation, documentation; introduction to programming; individual and group design projects.