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Electronic Theses and Dissertations

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Full-Text Articles in Engineering

Charged-Particle Interactions To Generate Novel Coatings And Materials, Pradnya D. Rao Feb 2022

Charged-Particle Interactions To Generate Novel Coatings And Materials, Pradnya D. Rao

Electronic Theses and Dissertations

A typical paper coating formulation contains anionically charged pigments and latex to provide a high-quality surface for printing. However, during application and drying, the latex can migrate to the surface or deep into the paper, resulting in weak coating layers or the need to use a high latex content to obtain the same strength properties. In this thesis, we have explored the introduction of cationically charged particles into the suspension as a way to reduce the amount of binder in the coatings, improve coating strength and reduce binder migration. With these aims in mind, we have generated cationic precipitated calcium ...


Analysis Of Bio-Alcohols With Mie-Scattering And Ltc For Lowered Emissions In Pcci, Cesar E. Carapia Jan 2022

Analysis Of Bio-Alcohols With Mie-Scattering And Ltc For Lowered Emissions In Pcci, Cesar E. Carapia

Electronic Theses and Dissertations

An investigation was conducted on the optimal engine parameters for facilitating lower NOX and soot emissions of PCCI combustion with either ethanol or n-butanol. The PFI fuels selected were tested at loads of 3, 4, and 5 Bar IMEP for a total of 28 total combustion tests with variations made to the EGR% and boost pressure for each test in order to find the optimal emissions strategy. A Mie-scattering spray fuel analysis was also conducted on the three fuels to gain insight on their influence on combustion/emissions characteristics. It was found that ethanol had a greater average Sauter Mean ...


Comparative Analysis Of Winglet Efficiency On Supercritical Versus Traditionally Cambered Airfoils, Evan Cathers Jan 2022

Comparative Analysis Of Winglet Efficiency On Supercritical Versus Traditionally Cambered Airfoils, Evan Cathers

Electronic Theses and Dissertations

This study serves to define the performance of several industry-recognized and exploratory wing tip devices on aircraft wings utilizing contemporary supercritical airfoil geometry. For comparison, the same examination is performed on a wing comprised of traditionally cambered airfoils, the platform upon which winglets were initially developed. The supercritical wing design is based on that of the Airbus A320, while the conventional airfoil is based upon the Boeing 737-800 platform. Tip devices selected for analysis include blended, raked, split scimitar, fence, and spiroid winglets, as well as tip sails, characterized by the spreading of a bird’s primary flight feathers. Methodology ...


Classification Of Electropherograms Using Machine Learning For Parkinson’S Disease, Soroush Dehghan Jan 2022

Classification Of Electropherograms Using Machine Learning For Parkinson’S Disease, Soroush Dehghan

Electronic Theses and Dissertations

Parkinson’s disease (PD) is a neurodegenerative movement disorder that progresses gradually over time. The onset of symptoms in people who are suffering from PD can vary from case to case, and it depends on the progression of the disease in each patient. The PD symptoms gradually develop and exacerbate the patient’s movements throughout time. An early diagnosis of PD could improve the outcomes of treatments and could potentially delay the progression of this disorder and that makes discovering a new diagnostic method valuable. In this study, I investigate the feasibility of using a machine learning (ML) approach to ...


Improving Quantification Of Mitral Regurgitation Through Computational Fluid Dynamics And Ex Vivo Testing, Alexandra Flowers Jan 2022

Improving Quantification Of Mitral Regurgitation Through Computational Fluid Dynamics And Ex Vivo Testing, Alexandra Flowers

Electronic Theses and Dissertations

Mitral regurgitation (MR) is a prominent cardiac disease affecting more than two million people in the United States alone. In order for patients to receive proper therapy, regurgitant volume must first be quantified. As there are an array of methods to do so, the proximal isovelocity surface area (PISA) method continues to be the most accurate and clinically used method. However, there are some difficulties obtaining the necessary measurements need for this when performing transthoracic echocardiography. This study aims to evaluate and present techniques that may be used to more accurately quantify regurgitation through ex vivo testing and computational fluid ...


Monitoring Of State Transitions In Extreme Environment Application Materials Using Fiber Bragg Grating Sensors, Sabuj Khadka Jan 2022

Monitoring Of State Transitions In Extreme Environment Application Materials Using Fiber Bragg Grating Sensors, Sabuj Khadka

Electronic Theses and Dissertations

By embedding both a single fiber Bragg grating (FBG) sensor and a thermocouple (TC) during the manufacturing for extreme environment applications of certain classes of materials such as metals and polymers, a novel in-situ approach was developed to precisely monitor their entire manufacturing processes. This novel monitoring technique was able to identify many characteristic points during the curing of room and high-temperature epoxies and the solidification processes of metal alloys composed of tin and bismuth which were selected in this research purely for verification purposes. Some of the characteristic points identified for the epoxies were: (i) the gel point, (ii ...


Data-Enabled Distribution Grid Management, Zohreh Sadat Hosseini Jan 2022

Data-Enabled Distribution Grid Management, Zohreh Sadat Hosseini

Electronic Theses and Dissertations

In 2020, U.S. electric utilities installed more than 94 million advanced meters, which brought the percentage of residential customers equipped with smart meters to 75%. This significant investment allows collecting extensive customer data at the distribution level, however, the data are not currently leveraged effectively to help with system operations. This dissertation aims to use the smart meters’ data to improve the grid’s reliability, stability, and controllability by solving two of the most challenging problems at the distribution level, namely distribution network phase identification and outage identification.

Distribution networks have typically been the least observable and most dynamic ...


Using Long Short-Term Memory Networks To Make And Train Neural Network Based Pseudo Random Number Generator, Aditya Harshvardhan Jan 2022

Using Long Short-Term Memory Networks To Make And Train Neural Network Based Pseudo Random Number Generator, Aditya Harshvardhan

Electronic Theses and Dissertations

Neural Networks have been used in many decision-making models and been employed in computer vision, and natural language processing. Several works have also used Neural Networks for developing Pseudo-Random Number Generators [2, 4, 5, 7, 8]. However, despite great performance in the National Institute of Standards and Technology (NIST) statistical test suite for randomness, they fail to discuss how the complexity of a neural network affects such statistical results. This work introduces: 1) a series of new Long Short- Term Memory Network (LSTM) based and Fully Connected Neural Network (FCNN – baseline [2] + variations) Pseudo Random Number Generators (PRNG) and 2 ...


Assessment Of Aged Woodchip Bioreactor Physical And Hydraulic Properties, Shelby Duncan Jan 2022

Assessment Of Aged Woodchip Bioreactor Physical And Hydraulic Properties, Shelby Duncan

Electronic Theses and Dissertations

Denitrifying woodchip bioreactors are a critical tool for mitigating nitrate loading to downstream water bodies. The properties of the woodchip are a key factor in the design of the bioreactor which are usually designed to optimize that retention time of the water being treated. Retention time is affected by active flow volume, porosity, and flow rate. As a bioreactor ages, the carbon material will break down and, in some cases, sedimentation will occur within the bioreactor. Both processes will affect the porosity and hydraulic performance of the bioreactor. When flow through the bioreactor is significantly different than the original design ...


Repairable Precast Bridge Bents For Seismic Events, Kallan Hart Jan 2022

Repairable Precast Bridge Bents For Seismic Events, Kallan Hart

Electronic Theses and Dissertations

Concrete bridge columns are designed to withstand earthquakes by undergoing large displacements. Current seismic bridge codes guarantee collapse prevention, but damage to concrete and longitudinal reinforcement often requires demolition of the structure. Repairable detailing and advanced bridge construction connections may be utilized in concrete bridge columns to allow for quick construction as well as replacement of damaged reinforcement after an earthquake. This detailing may be an attractive alternative to bridge owners to reduce construction and replacement costs as well as ensure the functionality of critical routes after an earthquake. Three repairable precast bridge columns with exposed longitudinal reinforcement were tested ...


Managing Water Quantity And Quality With Subsurface Drainage In Eastern South Dakota, Morghan Hurst Jan 2022

Managing Water Quantity And Quality With Subsurface Drainage In Eastern South Dakota, Morghan Hurst

Electronic Theses and Dissertations

Moisture extremes (excess and deficit) impact crop loss and water quality. Due to excessively wet springs and dry summers, crop damage can occur within the same county or field within the same year. To determine the magnitude of this problem in eastern South Dakota, indemnified crop insurance data for drought and excessive moisture claims were assessed for the years 1991-2020 for the occurrence of both excess moisture and drought in four counties in eastern South Dakota. Results show that there is greater than a 70% chance of the moisture extremes happening in the same year, making subsurface drainage, controlled drainage ...


Study On Performance Of Pruned Cnn-Based Classification Models, Mengling Deng Jan 2022

Study On Performance Of Pruned Cnn-Based Classification Models, Mengling Deng

Electronic Theses and Dissertations

Convolutional Neural Network (CNN) is a neural network developed for processing image data. CNNs have been studied extensively and have been used in numerous computer vision tasks such as image classification and segmentation, object detection and recognition, etc. [1] Although, the CNNs-based approaches showed humanlevel performances in these tasks [2], they require heavy computation in both training and inference stages, and the models consist of millions of parameters. This hinders the development and deployment of CNN-based models for real world applications. Neural Network Pruning and Compression techniques have been proposed [3, 4] to reduce the computation complexity of trained CNNs ...


A Non-Reacting Passive Scalar Comparison Of Starccm And Openfoam In A Supersonic Cavity Flame Holder, Thomas Nuese Jan 2022

A Non-Reacting Passive Scalar Comparison Of Starccm And Openfoam In A Supersonic Cavity Flame Holder, Thomas Nuese

Electronic Theses and Dissertations

The scramjet engine equipped with a modern-day airliner would allow for very quick travel across the United States. The major problem is that designing such an engine and testing it to make sure it is safe would cost millions if not billions of dollars. Computational fluid dynamics allows for complex designs to be tested but can still take many days, weeks, or even months to complete. With the use of computational fluid dynamics (CFD), the scramjet engine can be analyzed to determine a quicker way to test and develop a reliable configuration in addition to analyzing the effects of different ...


Efficient Numerical Optimization For Parallel Dynamic Optimal Power Flow Simulation Using Network Geometry, Rylee Sundermann Jan 2022

Efficient Numerical Optimization For Parallel Dynamic Optimal Power Flow Simulation Using Network Geometry, Rylee Sundermann

Electronic Theses and Dissertations

In this work, we present a parallel method for accelerating the multi-period dynamic optimal power flow (DOPF). Our approach involves a distributed-memory parallelization of DOPF time-steps, use of a newly developed parallel primal-dual interior point method, and an iterative Krylov subspace linear solver with a block-Jacobi preconditioning scheme. The parallel primal-dual interior point method has been implemented and distributed in the open-source PETSc library and is currently available. We present the formulation of the DOPF problem, the developed primal dual interior point method solver, the parallel implementation, and results on various multi-core machines. We demonstrate the effectiveness our proposed block-Jacobi ...


Characterization Of Shear Strength And Cracking Resistance Of A Chemically Stabilized Clayey Soil, Abdulaziz Alhawiti Jan 2022

Characterization Of Shear Strength And Cracking Resistance Of A Chemically Stabilized Clayey Soil, Abdulaziz Alhawiti

Electronic Theses and Dissertations

Improving the engineering properties of the subgrade soil by means of chemical stabilization is known to enhance the construction conditions in plastic soils and result in a reduction in design thickness requirements of the base, subbase, and wearing course in a layered pavement structure. This can also potentially lead to an increase in pavement life. This study was undertaken to study the effect of hydrated lime and Portland cement used as a stabilizing agents on the strength properties and the cracking resistance of a clayey soil collected from South Dakota. Hydrated lime was mixed with the collected soil by 2 ...


Numerical Study Of Laryngeal Control Of Phonation Using Realistic Finite Element Models Of A Canine Larynx, Biao Geng Dec 2021

Numerical Study Of Laryngeal Control Of Phonation Using Realistic Finite Element Models Of A Canine Larynx, Biao Geng

Electronic Theses and Dissertations

While many may take it for granted, the human voice is an incredible feat. An average person can produce a great variety of voices and change voice characteristics agilely even without formal training. Last several decades of research has established that the production of voice is largely a mechanical process: i.e., the sustained vibration of the vocal folds driven by the glottal air flow. Since one only has a single pair of vocal folds, the versatility comes with the ability to change the mechanical status of the vocal folds, including vocal fold length and thickness, tension, and level of ...


Thermal And Mechanical Numerical Modeling Of Extrusion-Based 3d Printed Reinforced Polymers For Selecting Manufacturing Process Parameters, Sunil Bhandari Dec 2021

Thermal And Mechanical Numerical Modeling Of Extrusion-Based 3d Printed Reinforced Polymers For Selecting Manufacturing Process Parameters, Sunil Bhandari

Electronic Theses and Dissertations

Extrusion-based 3D printing of thermoplastic polymer composites manufactures parts that have nonhomogenous, orthotropic, and process-dependent macro-scale material properties. As a part of the dissertation, research works were carried out to: • improve the interlayer mechanical properties and reduce the orthotropy, • use experimentally homogenized orthotropic material properties to numerically model the mechanical behavior of the non-homogenous orthotropic 3D printed parts, • create an efficient numerical thermal model to predict the process-dependent thermal history of the 3D printed part, and • aid the manufacturing process by selecting a suitable set of processing parameters based on a simplified sequentially coupled thermomechanical model. The dissertation presents four ...


Comparison Between Cpu And Gpu For Parallel Implementation For A Neural Network Model Using Tensorflow And A Big Dataset, Intisar Alkaabwi Dec 2021

Comparison Between Cpu And Gpu For Parallel Implementation For A Neural Network Model Using Tensorflow And A Big Dataset, Intisar Alkaabwi

Electronic Theses and Dissertations

Machine learning is a rapidly growing field that has become more common of late. Because of the demanding computational usage of machine learning, this field has many dimensions needing research. TensorFlow has been developed to deal with and analyze neural networks computation. In particular, TensorFlow is often used in one of the machine learning branches and is called deep learning. This work discusses the performance of a deep learning model to train a very large dataset with TensorFlow. It compares performance when the run happens on CPUs and on GPUs regarding the run time and speed. The run time is ...


Techno-Economics And Life Cycle Analysis Of Upgrading Woody Biomass To Diesel Blendstock, Aysan Najd Mazhar Dec 2021

Techno-Economics And Life Cycle Analysis Of Upgrading Woody Biomass To Diesel Blendstock, Aysan Najd Mazhar

Electronic Theses and Dissertations

Woody biomass conversion to transportation fuels have been developed as alternatives to fossil fuel production to reduce greenhouse gas emissions and to increase energy security. Fast pyrolysis, a thermochemical technology, has the potential to offer high efficiencies to produce liquid transportation fuels from woody biomass. Fast pyrolysis involves rapid heating of biomass particles in the absence of air at approximately 500°C and results in non-condensable gases, bio-oil (pyrolysis oil), and char as products. The pyrolysis oil can be upgraded via integrated mild hydrogenation and etherification processes to a high energy density fuel that can be blended with diesel for ...


Computer Modeling Using The Finite-Difference Time-Domain (Fdtd) Method For Electromagnetic Wave Propagation, Atheer A. Oufi Dec 2021

Computer Modeling Using The Finite-Difference Time-Domain (Fdtd) Method For Electromagnetic Wave Propagation, Atheer A. Oufi

Electronic Theses and Dissertations

The Finite-Difference Time-Domain (FDTD) technique is a numerical analysis modeling method to find the solutions of the partial derivatives in Maxwell’s equations to electromagnetic problems. In FDTD the electrical and magnetic fields components staggered in time and space by a method developed by Yee. The approximation of the solutions can be found using a set of updated equations.

In every simulation that utilizes the FDTD method, the factors of time and memory size are the two significant considerations. This study focused on reducing the computation time, as the time required to time-march the components of the electrical and magnetic ...


Gradient Generating Microfluidic Coculture System For Disease Modeling And Neural Development, Phaneendra Chennampally Dec 2021

Gradient Generating Microfluidic Coculture System For Disease Modeling And Neural Development, Phaneendra Chennampally

Electronic Theses and Dissertations

Cellular microenvironment or cell niche plays an important role in developmental biology and disease pathophysiology. Physical or chemical signals in microenvironment drive the cellular activity. These signaling molecules are generated from the surrounding cells/tissues as part of intercellular communication; a fundamental property of a cell. Dynamic profile of these signaling molecules in the microenvironment plays a pivotal role in transfer of molecular information from cell to cell in disease proliferation or fate determination. Recapitulating these signaling cues in an in vitro study is difficult to achieve using standard cell culture techniques. However microfluidic systems are capable of addressing these ...


Design, Quantification, And Strengthening Of Interface Interaction Between Aramid Fibers And Polymer Matrix, Karrar Al-Quraishi Dec 2021

Design, Quantification, And Strengthening Of Interface Interaction Between Aramid Fibers And Polymer Matrix, Karrar Al-Quraishi

Electronic Theses and Dissertations

Composites reinforced by aramid fibers may suffer poor interface interactions during mechanical loading due to the smooth and chemically inert surface of the fibers. Three main strategies have been used to improve the interface shear strength (IFSS) including increasing surface roughness, enriching fiber surface with functional groups, and surface coating with ceramic particles. Plasma treatment is usually employed to functionalize and roughen surface of the fibers, leading to strengthening of the interface between the fibers and polymer matrix. A concern for fibers reinforced polymers is that the IFSS would significantly decrease once the composite is exposed to elevated temperatures. To ...


Determination Of Bridge Behavior Through Live-Load Testing And Advanced Numerical Analysis, Andrew Schanck Dec 2021

Determination Of Bridge Behavior Through Live-Load Testing And Advanced Numerical Analysis, Andrew Schanck

Electronic Theses and Dissertations

Bridges represent critical nodes in the United States’ transportation network, and an accurate understanding of their strength and durability is paramount to their continued use to transport people and goods. Traditionally, bridge assessment has been conducted through conventional beam-line analysis of isolated bridge components as specified by the American Association of State Highway and Transportation Officials (AASHTO). Although this method is reasonable for relatively new structures whose behavior are well understood, it can lead to significant over-conservative estimates of live-load capacity for older structures and for new types of structure for which design bases are still being developed. For such ...


Implementation Of An Improved Image Enhancement Algorithm On Fpga, Prit Ghanshyambhai Patel Oct 2021

Implementation Of An Improved Image Enhancement Algorithm On Fpga, Prit Ghanshyambhai Patel

Electronic Theses and Dissertations

Image processing plays very crucial role in this digital human world and has rapidly evolved with the development of computers, mathematics and the real-life demand of variety of applications in wide range of areas. This wide range of areas includes remote sensing, machine/ robot vision, pattern recognition, medical diagnosis, video processing, military, agriculture, television, etc. Image processing has two important components which are image enhancement and information extraction. Since image enhancement works at the front end with the initial raw inputs, it works like a backbone in image processing. When it comes to implementing these image enhancement techniques and developing ...


Microstrip Array Antenna For Wireless Power Transfer, Sahereh Sahandabadi Oct 2021

Microstrip Array Antenna For Wireless Power Transfer, Sahereh Sahandabadi

Electronic Theses and Dissertations

In this thesis, a triangular microstrip patch antenna is used to transfer wireless power at 2.4 GHz. First, the simple patch antenna is studied and its performance is investigated. Then, the new design is introduced to boost the efficiency and transmission coefficient of the simple patch antenna. Since the simple patch aimed to operate at 2.4GHz, its dimension is optimized to be 56mm with a reflection coefficient of -28.2 dB at the resonance frequency. An identical patch acting as a receiver is then placed in a 50mm distance to the main patch acting as a transmitter to ...


Performance Analysis And Improvement Of Electrochemical Impedance Spectroscopy For Online Estimation Of Battery Parameters, Marzieh Abaspour Ghadi Oct 2021

Performance Analysis And Improvement Of Electrochemical Impedance Spectroscopy For Online Estimation Of Battery Parameters, Marzieh Abaspour Ghadi

Electronic Theses and Dissertations

Battery internal impedance measurement is of great importance for a battery management system, which is tasked with ensuring the safety, efficiency, and reliability of a battery pack. Electrochemical impedance spectroscopy (EIS) is an active method of estimating battery impedance parameters, where an excitation signal spanning a wide frequency spectrum is applied to the battery to measure its response. Even though the EIS approach is accurate and reliable, it is limited to laboratory experiments due to its dependence on high-precision measurement systems. In order to benefit from the EIS approach in real-time applications, e.g., the battery management system of an ...


Finite Element Analysis Of Complex Vectorbloc Beam-Column Connections, Labiba Kalam Oct 2021

Finite Element Analysis Of Complex Vectorbloc Beam-Column Connections, Labiba Kalam

Electronic Theses and Dissertations

Steel modular construction provides an efficient alternative to traditional construction practices. A key component to modular construction is the connection between the individual modules, which hold the building together against applied loads such as gravity, snow, and wind. The VectorBloc connector is an innovative cast steel connector that is used in the connections between steel modules made from hollow structural steel (HSS) members. The current VectorBloc connector, called VB4, is limited in its uplift capacity and thus faces challenges when applied to structures facing high uplift forces. Thus, a new design of the VectorBloc connector, called VB6, with a focus ...


Predictive Model Of Air Dam Deflection Under Aerodynamic Loads, Chang Kyun Kang Oct 2021

Predictive Model Of Air Dam Deflection Under Aerodynamic Loads, Chang Kyun Kang

Electronic Theses and Dissertations

Plastic components are widely used on the exterior body of automotive vehicles. When the vehicle is moving, these components experience deformation caused by air flow. Simultaneously, the deformation affects the flow of air around the vehicle. This research is focused on developing virtual simulation techniques for determining the vehicle air dam behaviour under aerodynamic loads. The main objective of this research is to develop a fluid-structure interaction (FSI) methodology for predicting deflection of the air dam.

Computational Fluid Dynamics (CFD) and Finite Element Analysis (FEA) codes are coupled so that fluid pressure and air dam displacement parameters are exchanged. The ...


Wake Characteristics Of Wall-Mounted Finite Solid And Foam-Covered Cylinders, Subhadip Das Oct 2021

Wake Characteristics Of Wall-Mounted Finite Solid And Foam-Covered Cylinders, Subhadip Das

Electronic Theses and Dissertations

The wake characteristics of a wall-mounted finite foam-covered cylinder are explored by comparing the flow properties with the wake of a solid cylinder. The velocity data are acquired experimentally using planar particle image velocimetry (PIV) and numerically by large eddy simulation at Reynolds number of 35100 based on the flow depth and 13100 based on the cylinder diameter. The wake characteristics may vary significantly if the approach flow properties change and also depend on the relative height of the boundary layer thickness with respect to the cylinder height. Therefore, it is a necessity to achieve a fully developed approach flow ...


Development Of Superior Energy Absorbing Devices With Adaptive Capabilities Utilizing Hybrid Cutting/Clamping Deformation Modes, John Magliaro Oct 2021

Development Of Superior Energy Absorbing Devices With Adaptive Capabilities Utilizing Hybrid Cutting/Clamping Deformation Modes, John Magliaro

Electronic Theses and Dissertations

The primary objective of this research was to investigate cutting deformation modes, employing higher-bladed cutters (i.e. 6 or more evenly space blades), with an emphasis on superior energy absorbing capabilities in comparison to axial crushing, the current state-of-the-art. A series of test cases involving AA6061 extrusions were identified utilizing analytical models of the steady-state cutting force and mean crushing force and selecting geometries where the ratio of the former force normalized with respect to the latter exceeded unity. Quasi-static testing confirmed that the total energy absorbing capacity could be exceeded while simultaneously reducing the peak force under quasi-static loading ...