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Full-Text Articles in Engineering

State Estimation And Prediction Based On Simplified First Principle Model Of Lithium-Ion Batteries In Lebesgue Sampling Framework, Enhui Liu Aug 2024

State Estimation And Prediction Based On Simplified First Principle Model Of Lithium-Ion Batteries In Lebesgue Sampling Framework, Enhui Liu

Theses and Dissertations

State-of-charge (SOC) and remaining-dischargeable-time (RDT) are critical states of Lithium-ion batteries (LIBs). SOC indicates the available charge stored in LIBs compared to the total charge capacity of LIBs, while RDT refers to the remaining dischargeable time that LIBs can support under given loading profiles. Accurate SOC estimation and RDT prediction play important roles in guaranteeing the safe and efficient operation of batteries in real applications.

Taking advantage of high fidelity of simplified first principle (SFP) model of LIBs, this research aims to accurately estimate SOC and predict RDT. Firstly, this research establishes an SFP model to describe the battery internal …


Application Of Machine Learning Techniques And The Unscented Kalman Filter To Real-Time Gas Turbine Clearance Prediction, Donald Earl Floyd Aug 2024

Application Of Machine Learning Techniques And The Unscented Kalman Filter To Real-Time Gas Turbine Clearance Prediction, Donald Earl Floyd

Theses and Dissertations

The growth in renewable energy sources and retirement of large baseload coal-fired power stations has led to an accompanying decrease in reliability and security of the electrical grid. Since renewable energy sources are typically non-dispatchable, this can lead to blackouts and/or brownouts for customers. Heavy duty gas turbine power plants (HDGT) offer a solution to this problem. HDGTs are dispatchable, clean, and offer flexibility in the fuel they consume, but operational limitations must be well understood to fully exploit their benefits.

One of the main operational limitations is the tip clearances in the gas turbine. In many cases, the gas …


The Study And Development Of Autonomous Scarf Repair For Composite Structures: A Focus On Advanced Air Mobility Vehicles, Stephen Hilton Aug 2024

The Study And Development Of Autonomous Scarf Repair For Composite Structures: A Focus On Advanced Air Mobility Vehicles, Stephen Hilton

Theses and Dissertations

“I’m sorry I haven’t been able to truly give you a solution to thermoplastic repair” – Arnt. Director GKN Global Tech Center, 2023

The aerospace industry has a prevalence of composite materials due to their outstanding benefits to the mechanical properties of structures while serving to reduce the overall structure weight. With the development of the Advanced Air Mobility market, there is an anticipated growth in the number of composite structures. Also, with the manufacturing environment of the 21st century, these composite structures are more and more being made using thermoplastic composites that can be recycled at the end of …


A Study Of Direct Sensitivity Method Solving Optimal Control Problems With Single And Multiple Time Grids With An Application In An Experimental Hybrid System, Hainan Wang Aug 2024

A Study Of Direct Sensitivity Method Solving Optimal Control Problems With Single And Multiple Time Grids With An Application In An Experimental Hybrid System, Hainan Wang

Theses and Dissertations

Computational methods for optimal control are important for dealing with bottlenecks in industries. By implementing optimal operation strategies obtained from the computational methods into dynamic systems, objectives such as saving energy, reducing cost, exploiting potential, and improving efficiency can be achieved. Computational methods for optimal control have been used in a broad range of disciplines, including aeronautics and astronautics, oil and chemical engineering, power systems, clean energy, biomedical engineering, economics, and management. Due to the great application value of optimal control, its computational methods have drawn worldwide attention. Direct methods are most effective in computational methods for optimal control. Direct …


Enhanced Two-Phase Heat Spreading Enabled By Dropwise Condensation, Kai Luo Aug 2024

Enhanced Two-Phase Heat Spreading Enabled By Dropwise Condensation, Kai Luo

Theses and Dissertations

The rapidly increasing power density of electronic systems has raised challenges for thermal management. Efficient heat spreading plays an important role in distributing high-density heat to the large-area heat sink and maintaining the junction temperature below the temperature limit during operation. Vapor chambers, a type of flat heat pipe utilizing two-phase heat transfer and fast travel of vapor flow, can achieve far more efficient two-dimensional heat spreading than most conduction-based thermal ground plane materials. By promoting dropwise condensation in vapor chambers, the thermal performance and scalability can be further improved due to the enhanced condensation heat transfer and unique droplet …


Crystal Plasticity Modeling Of Heterogeneous Microstructure Of Additively Manufactured Metals, Md Mahabubur Rohoman Aug 2024

Crystal Plasticity Modeling Of Heterogeneous Microstructure Of Additively Manufactured Metals, Md Mahabubur Rohoman

Theses and Dissertations

Additive manufacturing (AM) has emerged as a promising technique in the manufacturing industry for producing complex metal components as it provides shape freedom and simplistic processing chain.

Powder bed fusion is the widely used AM technique that uses laser or electron beam as the energy source to melt the metal powder and deposit it in a layer-by-layer fashion. While doing so, the previously molten layers are constantly are in re-heating and re-cooling processes which end up creating an intricate solidification for the deposited layers. Due to the complexity involved in the thermal cycles for the solidification process, columnar grains develop. …


Experimental And Computational Understanding Of Solid Oxide Iron Air Battery Performance, Chaitali Morey Aug 2024

Experimental And Computational Understanding Of Solid Oxide Iron Air Battery Performance, Chaitali Morey

Theses and Dissertations

Long-duration energy storage (LDES) (10+ hours) is considered a key technical solution for a widespread penetration of renewable energy into the utility market. However, the currently available storage technologies are limited to less than 10 hours for cost reasons. The benchmark Li-ion battery technology would be economically prohibitive if the storage time goes beyond 4 hours. Therefore, developing new low-cost LDES-compatible battery technologies is highly desirable. A solid oxide iron air battery (SOIAB) has been developed which consists of a reversible solid oxide cell (RSOC) and energy storage unit (ESU) of an iron bed. This battery is considered a promising …


High-Rate Production Of Thermoplastic Composite Structures For Urban Air Mobility Vehicles Utilizing Fastener-Free Assembly Methods, Robert H. Shumpert Aug 2024

High-Rate Production Of Thermoplastic Composite Structures For Urban Air Mobility Vehicles Utilizing Fastener-Free Assembly Methods, Robert H. Shumpert

Theses and Dissertations

This study aimed to develop a manufacturing plan for a Thermoplastic fiber-reinforced propeller blade for urban air mobility applications. This propeller blade offer a few unique challenges including the complex geometries of the blade. Another important aspect of the blade is using fusion bonding methods to increase the strength of joints in the product while reducing weight from fasteners and adhesives. This manufacturing process will be validated by producing a physical demonstrator to ascertain the efficacy of the manufacturing techniques used. First, the techniques that will make up the manufacturing plan must be selected. To do this, a review of …


Dual-Phase Membrane Reactor And Calcium Oxide-Based Sorbents For High-Temperature Carbon Capture, Utilization And Storage, Kangkang Zhang Aug 2024

Dual-Phase Membrane Reactor And Calcium Oxide-Based Sorbents For High-Temperature Carbon Capture, Utilization And Storage, Kangkang Zhang

Theses and Dissertations

Greenhouse gases, especially CO2 emissions, are responsible for global warming and the reduction of greenhouse gases is vitally important for the sustainability of our modern society. Currently, the most mature CO2 capture, utilization and storage (CCUS) technology relies on flue gas “amine washing”, a costly and energy intense process that can negatively impact on the efficiency of existing power plants and the cost of electricity produced. Therefore, developing more efficient and cost-effective CCUS technologies is highly imperative. With the increasing production of natural gas in recent years, direct natural gas conversion into valuable chemicals also becomes more attractive than …


A Holistic Quality Management Model For Optimization Of Quality Assurance In Manufacturing, Devon Blakeney Clark Aug 2024

A Holistic Quality Management Model For Optimization Of Quality Assurance In Manufacturing, Devon Blakeney Clark

Theses and Dissertations

Quality Management (QM) is essential in manufacturing to ensure products are consistent and functional every time. Consumers expect high quality products that last, and industries unable to accomplish this are destined to fail. Therefore, product quality has always been at the forefront of manufacturer decision making, though it is normally viewed as a given more than as a goal. This means that businesses want quality because it is needed for their survival, but there has not been consideration for how to incorporate innovation into this essential field. Quality needs to be viewed holistically with regards to all manufacturing factors that …


Fission Product Thermodynamics, Solubility, And Extraction In Molten Salts And Lead, Richard Lee Fitzhugh Aug 2024

Fission Product Thermodynamics, Solubility, And Extraction In Molten Salts And Lead, Richard Lee Fitzhugh

Theses and Dissertations

Chemical behavior of fission products in systems relevant to two major advanced nuclear reactor systems, namely the lead-cooled fast reactor (LFR) and molten-salt reactor (MSR), has been studied with a heavy emphasis on thermodynamics. The behavior of fission products in molten salts is examined from a theoretical perspective, with an emphasis on the standard state used to define the thermodynamic activity. A standard state extrapolated from infinite dilution behavior, which is fairly common practice in electrochemistry, is found to facilitate faster, easier, and simpler analysis while retaining much of the accuracy of the complex Modified Quasichemical Model. Inductively-coupled plasma mass …


Void Formation During Liquid Composite Molding Under Varied Pressure With Mechanical Properties Validation, Neil Russell Thompson Aug 2024

Void Formation During Liquid Composite Molding Under Varied Pressure With Mechanical Properties Validation, Neil Russell Thompson

Theses and Dissertations

Composite materials have revolutionized products and how they are manufactured. Most large-scale aerospace companies utilize a carbon fiber pre-impregnated with a resin in conjunction with an autoclave to minimize voids, but it is very expensive and requires a great amount of space. The less expensive alternative to prepreg-autoclave processes is known as Liquid Composite Molding (LCM), in which the resin is brought into a mold via overpressure on the resin supply or by a vacuum in the mold. But this process is more prone to voids due to bubble formation. Voids are a critical issue as common failure modes such …


Quiescent Condensation Heat Transfer On Vertical Cicnt Structured Superhydrophobic Surfaces, Clint Mach Hubbard Aug 2024

Quiescent Condensation Heat Transfer On Vertical Cicnt Structured Superhydrophobic Surfaces, Clint Mach Hubbard

Theses and Dissertations

This study experimentally investigates the impact of the subcooling magnitude, the carbon-infiltrated carbon nanotube (CICNT) diameter, the time duration of condensation, and amount of non-condensable gases on the nature of dropwise condensation and condensate removal, and heat flux and heat transfer coefficient measurements. Experiments were conducted in a vacuum chamber on a vertically oriented test CICNT surface. The CICNT diameter was varied between 15-120 nm and the subcooling ranged from 0.5-9 °C. Each test ran for a duration of at least one hour and video was recorded at 20-minute intervals. Three modes of condensation were observed: drop jumping, drop wetting …


Behavior Of Reinforced Lightweight Cellular Concrete Backfill For Mechanically Stabilized Earth Walls With Welded Wire Reinforcements, Cole Max Larsen Aug 2024

Behavior Of Reinforced Lightweight Cellular Concrete Backfill For Mechanically Stabilized Earth Walls With Welded Wire Reinforcements, Cole Max Larsen

Theses and Dissertations

Lightweight cellular concrete (LCC) consists of a mixture of cement, water, and a pre-formed foam. The pre-formed foam entrains a high proportion of air voids into the cement water slurry at the time of casting, decreasing the product's overall weight. LCC is also a viable alternative when low native soil strengths prevent the use of traditional backfill methods through mitigating settlement and increasing strength. Due to these benefits, the use of LCC behind mechanically stabilized earth (MSE) walls is gaining popularity. Despite LCC gaining popularity behind MSE walls, the exact nature of the failure envelope is poorly understood. The pullout …


Tools For Planning Multi-Axis Vibration Qualification Tests, Marcus Edward Behling Aug 2024

Tools For Planning Multi-Axis Vibration Qualification Tests, Marcus Edward Behling

Theses and Dissertations

Vibration qualification testing is necessary to ensure that components will endure vibration-induced damage in flight. Multi-axis tests have shown the potential for improvement over single-axis tests, though they require increased planning. This work focuses on planning three critical aspects of these tests: the amount of operational next assembly to include in the test, the size of shakers to use, and the number of shakers to use. Next assembly selection is studied by varying the amount of next assembly included in the lab test, performing physical tests, and comparing the accuracy of environment reconstruction in each test. In doing so, a …


Zno Based Chemiresistive Sensor For Ammonia Detection, Anna Thomas Aug 2024

Zno Based Chemiresistive Sensor For Ammonia Detection, Anna Thomas

Theses and Dissertations

This work aims on the development of nanostructured sensing elements based on ZnO for detecting ammonia, specifically designed for applications in poultry and farm fields. To achieve this objective, we prepared sensing elements, including ZnO, CuO, WO3, NiO, ZnO/CuO, ZnO/WO3, ZnO/NiO, and rGO/ZnO, using the spray pyrolysis technique. Structural, morphological, and compositional analyses were studied using X-ray Diffraction (XRD), Field Emission Microscope (FESEM), and X-ray Photoelectron Spectroscopy (XPS), respectively. The vapour/gas detection studies of fabricated sensing elements were carried out in a home built sensing chamber.

The single oxides, ZnO, CuO, WO3, demonstrated ammonia detection in the range of 5-100 …


Design For Pullout Resistance And Global Stability Of Metallic Reinforcements In Mse Walls With Lightweight Cellular Concrete Backfill, Joshua Curt Peterson Aug 2024

Design For Pullout Resistance And Global Stability Of Metallic Reinforcements In Mse Walls With Lightweight Cellular Concrete Backfill, Joshua Curt Peterson

Theses and Dissertations

Lightweight cellular concrete (LCC) is a type of concrete that has reduced density and weight compared to traditional concrete. This is achieved by incorporating a large amount of air- filled cells or voids into the mixture. The resulting material is lighter, yet still possesses considerable strength and durability, making it suitable for a range of construction applications, especially in the case of retaining walls because of its reduced weight. Unlike traditional concrete, which can be extremely heavy and place significant stress on the supporting structure, lightweight cellular concrete reduces the pressure on the retaining wall, helping to prevent deformation and …


Demand Side Management Through Integrated Water Distribution Systems And Smart Irrigation Controllers, Nathan T. Lunstad Aug 2024

Demand Side Management Through Integrated Water Distribution Systems And Smart Irrigation Controllers, Nathan T. Lunstad

Theses and Dissertations

The innovation of electrical utilities in creating smart electrical grids has superseded that of water utilities in analogous efforts. While many water utilities are now using smart water technologies, they lack the virtual command center that allows for two-way communication for more effective forecasting, load balancing, preventive methods, emergency and master planning, and level of service delivery while ensuring environmental justice and enhancing the responsible use of resources. In this dissertation, I propose the idea of the Integrated Water Distribution System (IWDS) to overcome this challenge. IWDS coordinates management of water supply and demand in a way that benefits both …


Exploring Co-Manipulation Via A New Decomposition Of Interaction Force And An Exploration Of Signal Space In Multi-Agent Motion Primitives, Kody Blaine Shaw Aug 2024

Exploring Co-Manipulation Via A New Decomposition Of Interaction Force And An Exploration Of Signal Space In Multi-Agent Motion Primitives, Kody Blaine Shaw

Theses and Dissertations

Co-manipulation is when two or more people work together to move an object. In this work, we consider the physical co-manipulation of objects that are large and heavy enough that they are more easily handled by two or more participants. We currently lack a fundamental understanding of how people perform such tasks together, both the basic signals they use to communicate and how those signals are mapped to actions and behaviors. This work builds upon the existing body of knowledge to improve our understanding of physical co-manipulation. Specifically, interaction forces are often considered a key method for information transfer in …


Tribology Of Mos2 Thin Films Stabilized By A Chromium Underlayer And Max Phase, Nihal Ahmed Aug 2024

Tribology Of Mos2 Thin Films Stabilized By A Chromium Underlayer And Max Phase, Nihal Ahmed

Theses and Dissertations

MoS2 is a popular solid lubricant with limited application at room temperature due to its’ sensitivity to atmospheric oxygen and humidity. This thesis focuses on the stabilization of molybdenum disulfide (MoS2) coatings on aluminum substrates to enhance their tribological performance at room temperature. MoS2 exhibits exceptional lubricating properties in vacuum conditions, but its reactivity with atmospheric oxygen leads to the formation of abrasive molybdenum trioxide (MoO3), restricting its effectiveness in ambient environments. This thesis investigates the effects of a Chromium underlayer and the incorporation of MAX phase (Ti3SiC2) on the tribological performance and chemical stability of MoS2 solid lubricant. Physical …


Tribological Analysis Of Heat Treatments On Medical Grade Cobalt Chromium Molybdenum Alloys, Samuel Edis Bowden Aug 2024

Tribological Analysis Of Heat Treatments On Medical Grade Cobalt Chromium Molybdenum Alloys, Samuel Edis Bowden

Theses and Dissertations

Cobalt chromium molybdenum (CoCrMo) has many material properties that make it desirable as a medical hip implant. Due to the range of heat treatments available and the resulting material properties that are present in medical device manufacturing using CoCrMo, many implants are not able to withstand both the chemical and physical wear necessary as a hip replacement. This research looks to examine various heat treatments and their resulting properties to find a desirable heat treatment for CoCrMo in hip implant bearing surfaces. This study was accomplished by using five distinct variations of heat treatment on forged CoCrMo alloy that would …


Exploring The Link Between Travel Behavior And Mental Health, Emily Kae Youngs Aug 2024

Exploring The Link Between Travel Behavior And Mental Health, Emily Kae Youngs

Theses and Dissertations

This study explores the critical link between travel behavior and mental health, focusing on young adults who have expressed suicidal ideation. By analyzing how daily activities and movement patterns impact mental well being, the research aims to explore travel related mental health approaches for individuals. The importance of this work lies in its potential to improve the quality of life for individuals by informing more personalized and effective mental health strategies. Through comprehensive data analysis and statistical modeling, the research aims to uncover insights into how travel behavior influences motivation levels and mental well-being across different neurological and physiological groups. …


Engineering Cell-Free Protein Synthesis Biosensors For Point Of Care Use, Tyler Jordan Free Aug 2024

Engineering Cell-Free Protein Synthesis Biosensors For Point Of Care Use, Tyler Jordan Free

Theses and Dissertations

Diagnostic tests can dramatically improve and save lives. Survival rates and patient outcomes related to cancer and other diseases can be improved when routine testing guides personalized treatment. Highly accurate laboratory tests exist for thousands of biomarkers, including those of interest in this dissertation, but cost and complexity limit access to life-saving lab tests in many cases throughout the world. To fill this need and increase accessibility of diagnostics, in this report we report our engineering advancements towards portable biosensors for colorimetric detection of glutamine, endocrine disrupting compounds (EDC), and pathogenic RNA which are key biomarkers in cancer treatment monitoring, …


A Comparative Illustration Of Trip- And Activity-Based Modeling Techniques, Steven Hayden Atchley Aug 2024

A Comparative Illustration Of Trip- And Activity-Based Modeling Techniques, Steven Hayden Atchley

Theses and Dissertations

Activity-based travel demand models are generally considered superior to their trip-based counterparts, as activity-based models (ABMs) explicitly model individuals in contrast to the aggregate nature of trip-based models. There have been a number of comparisons between trip- and activity-based models, but these comparisons focus almost exclusively on the technical ability of the two model types, while not considering the practical benefits an ABM may or may not have to a transportation agency. This research performs a more holistic comparison between trip- and activity-based models, focused specifically on the practical differences between model types, both in terms of usability and capability …


Deep Learning For Improved Data-Driven Modeling Of Soft Robots For Model Predictive Control, Daniel Gray Cheney Aug 2024

Deep Learning For Improved Data-Driven Modeling Of Soft Robots For Model Predictive Control, Daniel Gray Cheney

Theses and Dissertations

The field of soft robotics is a growing research interest due to the unique benefits of soft robots over traditional robots, such as durability, compliance, and low-cost. These benefits allow soft robots to perform a variety of tasks that would be difficult for traditional robots, such as throwing, hammering, or whole-body manipulation. However, there is a significant variety of materials, actuators, and designs used in soft robotics. While helpful for completing more tasks, this variety also makes efficient modeling and control of soft robots difficult. In this thesis, an open-source repository, Modeling for Learned Dynamics (MoLDy), is presented. This repository …


Proposing A Matrix For Selecting Security Tools For Small Businesses, Nathan Jonathon Rowbotham Aug 2024

Proposing A Matrix For Selecting Security Tools For Small Businesses, Nathan Jonathon Rowbotham

Theses and Dissertations

Small businesses are increasingly under threat of cybersecurity attacks. An increasingly long list of tools with different purposes and coverage are available to help. But it can be difficult to choose which tools to use, particularly for a small business that may lack financial resources, expertise, and time. Research literature focuses on providing frameworks to follow to protect a business generally. Some research considers an aspect of creating a Security Operations Center. Other research describes the creation of a Security Operations Center as a Service with all the components the researchers deemed necessary. None of the current research literature seems …


Real-Time Dynamically Feasible B-Spline Trajectory Generation For Unmanned Aircraft, David Lavae Christensen Aug 2024

Real-Time Dynamically Feasible B-Spline Trajectory Generation For Unmanned Aircraft, David Lavae Christensen

Theses and Dissertations

Onboard aircraft systems must frequently plan dynamically feasible paths or trajectories to safely and quickly reach their goal position. Optimized B-splines are promising because they can guarantee kinematic feasibility in a computationally efficient manner and can be applied to a variety of vehicle models. However, current B-spline solutions do not adequately constrain trajectories to the physical limitation of the vehicles they are planning for, or are often too conservative. Most are also limited to path smoothing or require pre-optimized timing parameters. This thesis develops a real-time B-spline optimization-based trajectory generator capable of minimizing time while respecting the velocity, acceleration, and …


Design And Development Of A Clinical Decision Support System For The Diagnosis Of Parkinson’S Disease Using Artificial Intelligence, Saravanan S Aug 2024

Design And Development Of A Clinical Decision Support System For The Diagnosis Of Parkinson’S Disease Using Artificial Intelligence, Saravanan S

Theses and Dissertations

Parkinson’s disease (PD) is a degenerative neurological condition marked by motor symptoms like tremors, bradykinesia, and stiffness. It is observed that early and precise diagnosis of this disease is crucial, as that will have a significant impact on effective disease management and intervention. This thesis explores the technical feasibility of applying AI techniques to recognize patterns from spiral and wave drawings, which are usually a unique signature type for PD patients.

The focus of the work is to diagnose the disease through novel deep transfer learning techniques, to diagnose the severity of the disease, and also to develop effective model …


Development And Application Of A Particle-Based Reactor Network Model For Entrained Flow Gasifier Design, Eric Christian Monson Aug 2024

Development And Application Of A Particle-Based Reactor Network Model For Entrained Flow Gasifier Design, Eric Christian Monson

Theses and Dissertations

A novel particle-based reactor network model (PRNM) was developed to predict the performance of a dry-feed, pressurized, single-stage, slagging entrained flow gasifier under various operational parameters. This model provides improved detail of particle conversion as a function of gasifier location, particle size, and fuel type not available in standard reactor network models. The model inputs were designed to allow changes in geometry, firing rate, stoichiometric ratio, fuel type, and inlet gas composition. Key performance metrics included the gas and refractory temperature profiles, axial gas compositions, and particle burnout. PRNM used a network of idealized reactors to specify the flow field …


Design And Validation Of Sensing Knee Sleeve Rehabilitation Device Utilizing Large Deflection Strain Gauges, Kurt Christian Jensen Aug 2024

Design And Validation Of Sensing Knee Sleeve Rehabilitation Device Utilizing Large Deflection Strain Gauges, Kurt Christian Jensen

Theses and Dissertations

Total knee arthroplasty (TKA) procedures are increasingly common in the US and globally. However, rehabilitation outcomes may be negatively affected by limited access to physical therapy and patients' tendency to not fully adhere to recommended exercises between therapy sessions. This study aims to develop a remote system to aid rehabilitation, building upon recent sensor development at Brigham Young University, providing physical therapy-like biofeedback during unsupervised at-home exercises. The system developed by this research consists of three primary components: (1) a sensor array for measuring leg/knee biomechanics, (2) a machine learning algorithm to predict knee flexion angle from the sensor data, …