Engineering Commons^™

Experimental Investigation Of Image Distortion In A Mach 6 Hypersonic Flow, Ricky W. Green Ii

Theses and Dissertations--Mechanical and Aerospace Engineering

The image distortion that is inherently present when imaging through a flow field at hypersonic speeds was investigated. The original problem involves observation of the outside world from the inside an aircraft moving at hypersonic speeds. For this work, a Mach 6 hypersonic wind tunnel at Wright Patterson Air Force Base (WPAFB) was used and optical patterns were imaged with and without flow field characteristics. Two test campaigns were scheduled to conduct experiments that would provide answers to the proposed problem of the effect on observable aberrations through flow fields.

During the first test campaign, October 2017, optical patterns were …

Modeling Thin Layers In Material Response Solvers, Christen Setters

Theses and Dissertations--Mechanical and Aerospace Engineering

Thermal Protection Systems (TPS) are a necessary component for atmospheric entry. Most TPS contain thin layers of various materials such as ceramic coatings, pore sealers and bonding agents. When modeling TPS, these thin layers are often neglected due to the difference in scale between the TPS (centimeters) and the thin layers (micrometers). In this study, a volume-averaging flux-conservation method is implemented in the governing equations of a finite volume material response code. The model proposes the addition of a volume and area fraction coefficient which utilizes a weighted-averaging between the amount of thin layer and heat shield material in a …

Cell And Biofilm Adhesion Strength Quantified By The Laser Spallation Technique Yields A Novel Biocompatibility Metric, The Adhesion Index, James Boyd

Theses and Dissertations--Mechanical and Aerospace Engineering

Implant associated infections are one of the leading causes of hospital acquired infections in the United States. Medical orthopedic implant devices are designed to improve adhesion of relevant cells within our body. In the case of orthopedic implants, osteoblast cells will adhere and allow for proper integration with the body’s bones. However, virulent bacteria will also adhere onto medical implants and proliferate into biofilms. Bacterial biofilms become extremely difficult to eradicate clinically as antibiotics are not as effective, resulting in severe infections or loss of implant. The aim of this research is to quantify the adhesion strength differential between relevant …

Effective Modulus Of Cracked Bodies: A Finite Element Analysis, Alan Thomas Varughese

Theses and Dissertations--Mechanical and Aerospace Engineering

This thesis considers how cracks in an elastic body can alter the body’s elastic properties. In the present study the elastic property of note is the elastic or young’s modulus. It is desired to investigate to what extent the number and orientation of cracks can cause a reduction in the elastic modulus. Because of the complex nature of the elastic fields resulting from multiple cracks interacting together in a finite geometry an analytical solution is not possible or considered. Rather the Finite Element Method is used to determine the elastic response to a body with many cracks. This provides a …

A Computational Fluid-Structure Interaction Method For Simulating Supersonic Parachute Inflation, Jonathan Boustani

Theses and Dissertations--Mechanical and Aerospace Engineering

Following the successful landing of the Curiosity rover on the Martian surface in 2012, NASA/JPL conducted the low-density supersonic decelerator (LDSD) missions to develop large diameter parachutes to land the increasingly heavier payloads being sent to the Martian surface. Unexpectedly, both of the tested parachutes failed far below their design loads. It became clear that there was an inability to model and predict loads that occur during supersonic parachute inflation. In this dissertation, a new computational method that was developed to provide NASA with the capability to simulate supersonic parachute inflation is presented and validated. The method considers the loose …

Structural Optimization Of Space Transit Vehicle Concept, Hercules, James Philip Rogers

Theses and Dissertations--Mechanical and Aerospace Engineering

STRUCTURAL OPTIMIZATION OF SPACE TRANSIT VEHICLE CONCEPT, HERCULES:

A COMPARATIVE STUDY OF STRUCTURAL OPTIONS

Hercules is a vehicle concept developed by NASA Langley's Vehicle Analysis Branch to satisfy the need for sustainable transit between Earth, the moon, and Mars. Hercules features unprecedented abort capabilities and mission flexibility to aid in NASA's Mars campaign. By utilizing modern software to perform structural analysis and optimization for a large selection of stiffened panel concepts, beam concepts, and materials trends in the structural optimization emerge. These trends will be invaluable for the design of future spacecraft needed to fulfill similar roles.

The structural optimization …

Electromagnetic Formation Control Using Frequency Multiplexing, Zahra Abbasi

Theses and Dissertations--Mechanical and Aerospace Engineering

This dissertation addresses control of relative positions and orientations of formation flying satellites using magnetic interactions. Electromagnetic formation flight (EMFF) is implemented, in which each satellite is equipped with a set of electromagnetic coils to generate an electromagnetic field. Traditional EMFF technique applies DC magnetic fields which lead to a nonlinear and highly coupled formation dynamics that allow for only position or orientation control of the satellites. We present a new frequency multiplexing method, which is a technique that uses multi-frequency sinusoidal controls, to approximately decouple the formation dynamics and to provide enough controls for both position and orientation control. …

Additive Manufacturing In Personalized Medicine: Patient-Customized Solid Dose Medicines, And Patient-Customized Wound Care Device, Amir Najarzadeh

Theses and Dissertations--Mechanical and Aerospace Engineering

Personalized Medicine - from a one-size fits all to a tailored approach is the future in pharmaceutical therapeutics and medical applications. The aim of this study is demonstrate additive manufacturing in two personalized medicine applications: 1. Patient- customized solid dose medicines, and 2. Patient-customized wound care device. The aim of the first application is to develop an inexpensive and accurate method to design and fabricate patient-customized tablets. Particularly this paper focuses on fabricating and dose controlling of patient-customized extended release prednisolone-poly(vinyle alcohole) PVA. Dry-Blending, Wet Granulation, Extrusion, Spherionization, Hot melt extrusion (HME) was adopted to produce drug loaded prednisolone-PVA filaments …

Quantifying The Source And Pathway Of Dissolved Reactive Phosphate In Karst Drainage Of The Inner-Bluegrass, Cory Radcliff

Theses and Dissertations--Biosystems and Agricultural Engineering

In the Midwestern U.S. seasonal hypoxia experienced in the Gulf of Mexico and harmful algal blooms in inland freshwater ponds, lakes, and rivers are partly fueled by dissolved orthophosphate loadings from disturbed landscapes. Efforts to reduce dissolved reactive phosphate (DRP) loadings have had varying levels of success and have led to insufficient water quality improvements. Inefficiencies in conservation strategies can stem from poor understanding of phosphate source and flow pathway dynamics. This study focused on monitoring sources and flow pathways of dissolved reactive P in a karst agroecosystem with phosphatic limestone. We collected event water samples at the Camden Creek …

Extraction Of Micro- And Nano-Plastic Particles From Water Using Hydrophobic Natural Deep Eutectic Solvents, Jameson R. Hunter

Theses and Dissertations--Biosystems and Agricultural Engineering

The production of plastic and the amount of waste plastic that enters the environment increases every year. Synthetic polymers will gradually break down into particles on the micro- and nano-scale. The micro- and nano-plastics pose a significant ecological harm by transporting toxic chemicals and causing inflammation and cellular damage when ingested. Two common plastics are polyethylene terephthalate (PET) and Polystyrene (PS), and a newer bioplastic polylactic acid (PLA) that has become a popular alternative. Deep eutectic solvents are a recently discovered solvent composed of a hydrogen bond donor and hydrogen bond acceptor and have been proposed as a cheaper alternative …

Assessing The Use Of Lidar And Uav Technology For Monitoring Growing Alfalfa, Stuart Tucker Sheffield

Theses and Dissertations--Biosystems and Agricultural Engineering

Alfalfa is a popularly grown crop because of its value as a nutritious feed source for livestock. The efficient production of an alfalfa crop relies on the monitoring of certain parameters, like height, quality, and yield. Traditionally, producers have used manual measurements of alfalfa plant height to estimate the nutritive quality and yield of a growing alfalfa crop. Manual measurements of plant height are often labor intensive and provide low resolution data that is not acceptable for full field scale assessment of growing alfalfa. The two studies presented in this thesis offer detailed insight into the rapid and accurate monitoring …

Characterization And Upgrade Of Endocarp Biomass Derived Lignin To Value Added Products, Makua Vin-Nnajiofor

Theses and Dissertations--Biosystems and Agricultural Engineering

Lignin is an abundant biopolymer and a promising source of feedstock for high-value chemicals and energy materials, however, application methods of lignin into valuable products is yet to be fully explored. This study explores the valorization of lignin derived from lignin-rich endocarp biomass through the development of lignin-derived electrode materials. The chemical composition and cellular structure of the endocarps were characterized using HPLC and scanning electron microscopy (SEM) imaging. Mechanical properties of walnut and peach endocarps and preprocessing requirements were investigated using nanoindentation and specific energy consumption during grinding. Next, lignin was extracted from endocarps using deep eutectic solvent and …

Modeling Energy Flows In Floating In-Pond Raceways Utilizing Solar Power Back-Up, Bo Smith

Theses and Dissertations--Biosystems and Agricultural Engineering

The In-pond Raceway (IPR) is a novel option for production aquaculture, depending on water moving devices to provide constant flow. Device failure may result in catastrophic fish loss, requiring power backup systems to mitigate risk in case of power outages. Because these systems must be dependable and many suitable locations are remote, off-grid solar photovoltaic (PV) systems with battery storage have been considered since they eliminate need for utility power. Such systems can be hard to size and expensive. This study modeled system requirements using an energy balance to determine whether systems could withstand varying loads based on climatological conditions. …

Evaluating The Biotic Condition Of Restored Streams In Kentucky’S Inner Bluegrass Region, Charles Cole Crankshaw

Theses and Dissertations--Biosystems and Agricultural Engineering

Numerous stream restoration projects have been implemented in Kentucky’s Inner Bluegrass region to offset anthropogenic impacts. These projects range from full channel realignments to volunteer-led riparian installations. To assess the ability of said projects to restore stream habitat and biota, full restoration (n=12) and riparian (n=6) sites were compared to reference (n=6) and disturbed (n=12) sites using RBP and SVAP protocols, macroinvertebrate samples, and geomorphology. General trends for SVAP, RBP, and BI scores, starting with highest habitat or biotic quality, were reference sites, full and riparian restoration sites, then disturbed sites. The number of EPT taxa, another indicator of biological …

Comparing Beopt (Energyplus) Energy Predictions To Measured Circuit Level Energy Consumption Of 12 Similar Small Energy-Efficient Single-Family Residences, Braydi Mcpherson-Hathaway

Theses and Dissertations--Biosystems and Agricultural Engineering

Residential energy usage patterns change as a result of new building codes, renewable technologies, household electronics, and changes in occupancy habits. Building simulations have used end-use energy studies to inform occupancy profiles and overall usage characteristics for the building simulations. Building simulations allow designers, engineers, policymakers, code developers, and building owners to model proposed designs to new and existing buildings, thus it is imperative that the energy profiles used in the models are accurate. In this study, the building simulation engine BEopt is used to model energy-efficient homes recently constructed in Southern Kentucky. The homes have well defined building characteristics …

Ecg Arrhythmia Classification Using Discrete Wavelet Transformation, Hannah E. Chookaszian, Nathan D. Diekema

Electrical Engineering

Cardiovascular diseases (CVDs) are the highest leading cause of death worldwide with an approximate 17.9 million related deaths every year according to the World Health Organization (WHO). Electrocardiographic (EKG or ECG) signals are electrical signals measured in the heart and are the main indicator for pre-existing cardiac conditions. The application of deep learning methods such as artificial neural networks (ANN) will assist in the automated detection and classification of ECG signals. The current methods for ECG analysis are lacking in accuracy and reliability considering the level of risk involved with CVDs and the importance of a correct diagnosis. Clinicians use …

Software And Data Visualization Platform For Groundwater Level And Quality Monitoring System, Carlos M. Oppus, Ma. Aileen Leah G. Guzman, Maria Leonora C. Guico, Jose Claro N. Monje, Mark Glenn F. Retirado, John Chris T. Kwong, Genevieve C. Ngo, Annael J. Domingo

Electronics, Computer, and Communications Engineering Faculty Publications

Rapid urbanization and increasing population come with the increased extraction and use of groundwater resources. To track the effect of these activities on groundwater level and quantity; a system for real-time monitoring is devised. In this paper; we present a software system design that enables a locally-developed groundwater level and water quality monitoring hardware setup to gather water quality parameter data; send it to a cloud server; and present organized data for better visualization. The hardware setup consists of an Arduino microcontroller. Upon deployment; the hardware setup is linked to an Android application that connects to the web-based platform.

A Framework And Model For Managing And Sustaining A Successful Cross Functional Project Operations Team In A Multi-Project Manufacturing Environment In The Aerospace And Defense Industry, Anisulrahman Nizam

Electronic Theses and Dissertations, 2020-2023

Project manufacturing is a production manufacturing mode that develops and produces large and complex systems that is supplemented by project management techniques for planning and execution. Project manufacturing is better understood by examining it along with three other key areas: manufacturing, project management, and team management. Critical success factors for each of these areas have been examined in the literature but have not been examined in a real world setting in the aerospace and defense industry. This research examines the association between perspectives of project teams and senior management on critical success factors along the four identified dimensions of success …

Wind Turbine Main Bearing Fatigue Prognosis With Physics-Informed Machine Learning, Yigit Yucesan

Electronic Theses and Dissertations, 2020-2023

Unexpected main bearing failure on a wind turbine causes unscheduled maintenance and increased operation costs (mainly due to crane, parts, labor, and production loss). Unfortunately, historical data indicates that failure can happen far earlier than the component designed lives (due to manufacturing problems, for example). For the legacy fleet, which composes the majority of the installed basis, fatigue has become a major issue. Although bearing fatigue can be expressed with physics-informed models, they often inherent large uncertainties due to operation and unknown lubricant degradation mechanism. Apart from the unknown physics of failure, additional uncertainties associated with the grease that surrounds …

Econometric Frameworks For Energy Prediction, Naveen Chandra Iraganaboina

Electronic Theses and Dissertations, 2020-2023

Global warming and associated role of energy consumption across various sectors is a well-researched topic in recent years. Understanding current urban energy consumption patterns will allow us to understand how future energy consumption patterns will evolve. With electrification of vehicles and potentially altering culture of work from home, the energy usage at regional level would see a significant change in the future. The current PhD dissertation contributes to energy consumption analysis of a region by analyzing residential energy consumption, commercial energy consumption and transportation energy use by households. The aggregation of these energy consumption within a region contributes to the …

Numerical Behavior Of Steel H-Plies Repaired Using Layered Concrete Jacket, Fareh Waleed Abudawaba

Masters Theses

“This study developed finite element models (FEMs), using LS-Dyna software, to investigate the repair of corroded steel H-piles using concrete jacket. The concrete modeled as a layered material simulating 3D printed concrete. 3DPC is a new technology that can be used to repair or build structures without formwork by depositing concrete mixture layer by layer. For the 3DPC, this study investigated the feasibility of using alkali-activated concrete (AAC) synthesized using class C fly ash as the main binder. The fresh properties, extrudability, and buildability of the proposed concrete were investigated through open time and deformation tests, respectively. Hardened properties were …

Analysis Of Three-Phase Rectifier Via Three Different Control Methods And Switch Power Loss Comparison, Yichao Wang

All Graduate Theses, Dissertations, and Other Capstone Projects

Traditional uncontrolled or phase-controlled rectifiers have the defects of lower power factor and nontrivial higher harmonics which causes the low efficiency of power, bad power quality, and so on. However, PWM rectifiers overcome the drawbacks mentioned above. They reduce the higher harmonics yielding better sinusoidal current on the grid side, achieve unity power factor and bidirectional power flow, and have better dynamic performance. So, it is favored more by academia and widely applied in high-performance power electronics devices. In this paper, the PWM rectifier is analyzed and a comparison of the switch loss on three-phase rectifier using three different control …

Neural Network Supervised And Reinforcement Learning For Neurological, Diagnostic, And Modeling Problems, Donald Wunsch Iii

Masters Theses

“As the medical world becomes increasingly intertwined with the tech sphere, machine learning on medical datasets and mathematical models becomes an attractive application. This research looks at the predictive capabilities of neural networks and other machine learning algorithms, and assesses the validity of several feature selection strategies to reduce the negative effects of high dataset dimensionality. Our results indicate that several feature selection methods can maintain high validation and test accuracy on classification tasks, with neural networks performing best, for both single class and multi-class classification applications. This research also evaluates a proof-of-concept application of a deep-Q-learning network (DQN) to …

Novel New Modeling Procedure For Industrial Machinery With Nonlinear Connections, Steven Whitican

Dissertations, Master's Theses and Master's Reports

Given current timelines for rolling out production at volume, the ability to model portions of the production process is of paramount importance. To model production, high-fidelity models of production assets must be obtained. The production assets are comprised of linear and nonlinear structures. The linear structures are well understood and defined. Significant work has, and is, being done to understand the nonlinear components. This work focuses on developing and correlating a model of a nonlinear component. The component studied and modeled is a linear guide. Linear guides are bearings which facilitate translational motion of machine axes. An accurate model of …

Exploring The Impact Of Composite Material Fires And Associated Response Protocol On The Material Analysis During An Aircraft Accident Investigation, Flavio A. C. Mendonca, Natalie Zimmermann, Peng Hao Wang, Julius Keller

Publications

Metals, beginning in the 1930s, have been frequently used as the material of choice for aircraft construction (Hallion, 1978; Jakab, 1999). Common metals used in the aviation industry range from alloyed and heat-treated aluminum to titanium, magnesium, and superalloys, the latter used in specialized applications (Hallion, 1978; Mouritz, 2012). Nevertheless, a shift in aircraft construction – specifically in terms of the materials used – began in the 1970s, as composite materials were introduced into commercial aircraft (Mouritz, 2012). Among others, the increased use of composited materials was – and still is – propelled by the ability to manufacture comparative lightweight …

Test 2237: John Deere 8rx 340, Nebraska Tractor Test Lab

Nebraska Tractor Tests

ABOUT THE TEST REPORT AND USE OF THE DATA The test data contained in this report are a tabulation of the results of a series of tests. Due to the restricted format of these pages, only a limited amount of data and not all of the tractor specifications are included. The full OECD report contains usually about 30 pages of data and specifications. The test data were obtained for each tractor under similar conditions and therefore, provide a means of comparison of performance based on a limited set of reported data. EXPLANATION OF THE TEST PROCEDURES Purpose The purpose of …

Test 2245: Fendt 1156 Vario Mt, Nebraska Tractor Test Lab

Nebraska Tractor Tests

ABOUT THE TEST REPORT AND USE OF THE DATA The test data contained in this report are a tabulation of the results of a series of tests. Due to the restricted format of these pages, only a limited amount of data and not all of the tractor specifications are included. The full OECD report contains usually about 30 pages of data and specifications. The test data were obtained for each tractor under similar conditions and therefore, provide a means of comparison of performance based on a limited set of reported data. EXPLANATION OF THE TEST PROCEDURES Purpose The purpose of …

Test 2244: Fendt 1151 Vario Mt, Nebraska Tractor Test Lab

Nebraska Tractor Tests

ABOUT THE TEST REPORT AND USE OF THE DATA The test data contained in this report are a tabulation of the results of a series of tests. Due to the restricted format of these pages, only a limited amount of data and not all of the tractor specifications are included. The full OECD report contains usually about 30 pages of data and specifications. The test data were obtained for each tractor under similar conditions and therefore, provide a means of comparison of performance based on a limited set of reported data. EXPLANATION OF THE TEST PROCEDURES Purpose The purpose of …

Test 2239: Kubota M8-211, Nebraska Tractor Test Lab

Nebraska Tractor Tests

ABOUT THE TEST REPORT AND USE OF THE DATA The test data contained in this report are a tabulation of the results of a series of tests. Due to the restricted format of these pages, only a limited amount of data and not all of the tractor specifications are included. The full OECD report contains usually about 30 pages of data and specifications. The test data were obtained for each tractor under similar conditions and therefore, provide a means of comparison of performance based on a limited set of reported data. EXPLANATION OF THE TEST PROCEDURES Purpose The purpose of …

Real-Time Operation Of Microgrids, Salem Al-Agtash, Asma Alkhraibat, Mohamad Al Hashem, Nisrein Al-Mutlaq

Computer Science and Engineering

Microgrid (MG) systems effectively integrate a generation mix of solar, wind, and other renewable energy resources. The intermittent nature of renewable resources and the unpredictable weather conditions contribute largely to the unreliability of microgrid real-time operation. This paper investigates the behavior of microgrid for different intermittent scenarios of photovoltaic generation in real-time. Reactive power coordination control and load shedding mechanisms are used for reliable operation and are implemented using OPAL-RT simulator integrated with Matlab. In an islanded MG, load shedding can be an effective mechanism to maintain generation-load balance. The microgrid of the German Jordanian University (GJU) is used for …