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Masters Theses

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Full-Text Articles in Engineering

Euplectella Aspergillum’S Natural Lattice Structure For Structural Design & Stability Landscape Of Thin Cylindrical Shells With Dimple Imperfections, Zoe Y. Sloane Mar 2022

Euplectella Aspergillum’S Natural Lattice Structure For Structural Design & Stability Landscape Of Thin Cylindrical Shells With Dimple Imperfections, Zoe Y. Sloane

Masters Theses

The first portion of this thesis assesses the structural application of a bracing design inspired by the deep-sea sponge, Euplectella Aspergillum. Many studies have investigated the natural strength found in the unique skeletal structure of this species. The braced design inspired by the sponge features square frames with two sets of cross-braces that are offset from the corners of each frame, creating a pattern of open and closed cells. This study reports the results of multiple Finite Element Analysis (FEA) computations that compare the described bracing pattern to a more common bracing design used in structural design. The designs are ...


Application Of The New Iec International Design Standard For Offshore Wind Turbines To A Reference Site In The Massachusetts Offshore Wind Energy Area, Samuel C. Roach Mar 2022

Application Of The New Iec International Design Standard For Offshore Wind Turbines To A Reference Site In The Massachusetts Offshore Wind Energy Area, Samuel C. Roach

Masters Theses

This thesis summarizes the simulation and analysis performed for the MassCEC project described herein. The intent was to perform a “dry run” of the new IEC offshore wind turbine design standard, IEC 61400-3-1 and to illustrate the use of that standard in the Massachusetts Offshore Wind Energy Area. IEC 61400-3-1 is a design standard used to ensure wind turbine structural performance over the design life of the machine. Each installed wind turbine must be certified by a Certified Verification Agent using this standard before installation. The certification process typically uses a structural dynamics model to predict a turbine’s structural ...


Controlled Codelivery Of Mir-26a And Antagomir-133a With Osteoconductive Scaffolds To Promote Healing Of Large Bone Defects, Cole J. Ferreira Mar 2022

Controlled Codelivery Of Mir-26a And Antagomir-133a With Osteoconductive Scaffolds To Promote Healing Of Large Bone Defects, Cole J. Ferreira

Masters Theses

Often caused by trauma or tumor removal, large bone defects frequently result in delayed or non-union. The current gold standard for treatment is autograft. However, due to limitations, such as the size and location of the defect, these cannot always be utilized. A common alternative to autograft is the use of BMP-2 with a collagen scaffold, however, this treatment is limited by numerous side effects. In recent years, genetic materials such as microRNAs (miRNAs) have offered possible alternative therapies. MiRNAs are small non-coding RNA molecules that generally range from 20-24 nucleotides, serve as repressors of gene expression, and are involved ...


Development Of Phase Change Thermal Storage Medium: Cooking With More Power And Versatility, Martin Osei Jan 2022

Development Of Phase Change Thermal Storage Medium: Cooking With More Power And Versatility, Martin Osei

Masters Theses

With an Insulated Solar Electric Cooker (ISEC), a 100 W solar panel directly cooks food while providing 5W off-grid electricity access; but it cooks slowly. Storing the day’s energy with phase change thermal storage allows ISEC to cook more rapidly as well as cook after sunset. The ISEC is made by sticking a 3ohm resistive to an aluminum pot (inner phase change assembly PCA) where another cooking pot fits. The resistive heater is surrounded by a bigger pot (outer PCA) that contains the PCM and is tightly sealed. The solar panel is connected to the resistive heater with a ...


A Parametric Computational Fluid Dynamics (Cfd) Study Of In-Line Horizontal Axis Wind Turbines (Hawts) With Yaw, North Alyster Yates Dec 2021

A Parametric Computational Fluid Dynamics (Cfd) Study Of In-Line Horizontal Axis Wind Turbines (Hawts) With Yaw, North Alyster Yates

Masters Theses

Because of the constant use of non-renewable fossil fuels, and the enormous impact they have on global warming and pollution, there has been a push to use more eco-friendly and renewable sources for power. One such form is wind power via turbines. The most common form, Horizontal Axis Wind Turbines (HAWTs), can generate massive amounts of power. However, they also have a serious flaw in their design. As the wind passes through the swept area of the blades and past the tower, it creates massive disturbances in the airflow. These disturbances are called a ‘wake’. When trying to create a ...


Decomposition Approach To Parametric Nonconvex Regression; Nuclear Resonance Analysis, Jordan L. Armstrong Dec 2021

Decomposition Approach To Parametric Nonconvex Regression; Nuclear Resonance Analysis, Jordan L. Armstrong

Masters Theses

Parameterized nonconvex regression is a difficult problem for any optimization solver packages, often resulting in approximations and linearizations of the problem in order to be able to arrive a solution, if the problem is even solvable at all. These changes to the initial problem are largely dependent upon having appropriate domain knowledge and still often times result in a sizable gap between the achieved solution and the best true solution. We propose a novel method of decomposing the global problem into small, overlapping windows. Thus, the independent windows are now solvable. Subsequently, we offer a novel, sequential method of parameter ...


Assessing Mechanical Performance Of Dissimilar Steel Systems Made Via Wire-Arc Additive Manufacturing, Obed Daniel Acevedo Dec 2021

Assessing Mechanical Performance Of Dissimilar Steel Systems Made Via Wire-Arc Additive Manufacturing, Obed Daniel Acevedo

Masters Theses

Hot stamping is part of a specific type of metalworking procedure widely used in the automotive industry. This research seeks to help make hot stamp tooling component production more cost-effective by using large-scale additive manufacturing. Additive manufacturing can produce dissimilar steel components that can be more cost-effective and time-efficient and allow for complex geometries to be made. A dissimilar steel system consisting of 410 martensitic stainless steel and AWS ER70S-6 mild steel is proposed to make hot stamps, making them more cost-efficient. However, the material interface's mechanical behavior in 410SS-mild steel additively manufactured material systems is not well understood ...


Radiation Effects On Lithium Indium Diselenide Semiconductors As Neutron Imaging Detectors, Robert M. Golduber Dec 2021

Radiation Effects On Lithium Indium Diselenide Semiconductors As Neutron Imaging Detectors, Robert M. Golduber

Masters Theses

The studies presented in this work aim to improve upon the knowledge base of lithium indium diselenide (LISe) semiconductors to understand how the material behaves in high radiation environments and refine the process of turning it into a neutron detector. LISe has great potential as neutron imaging detector because of the high neutron absorption efficiency of its enriched 6Li component and its ability to discriminate between gamma-rays and neutrons. Its ability to remain functional after being irradiated with large amounts of neutron fluence has been tested and the change in its electro-optical properties with relation to fluence has been ...


Increasing Hydrophilicity And Transparency Of Diamond-Like Carbon Thin Films With Dopants For An Anti-Fogging Laparoscope Coating, Anna Bull Dec 2021

Increasing Hydrophilicity And Transparency Of Diamond-Like Carbon Thin Films With Dopants For An Anti-Fogging Laparoscope Coating, Anna Bull

Masters Theses

Laparoscopes are prone to fogging which can lead to a limited field of view during surgical procedures. Current methods of mitigating fogging issues are not efficient or can require costly modification to the laparoscope. Previous studies of diamond-like carbon (DLC) coatings found doping the films improved hydrophilic qualities, suggesting their possible use as antifogging coatings for laparoscopes. For this work, two series of DLC films, doped with either SiO and Al2O3 were investigated.

The biocompatibility, transparency, and stability of these films were assessed through cellular assays, spectrophotometry, and simulated body fluid soaking experiments. Contact angle and surface ...


Evaluation Of Robust Deep Learning Pipelines Targeting Low Swap Edge Deployment, David Carter Cornett Dec 2021

Evaluation Of Robust Deep Learning Pipelines Targeting Low Swap Edge Deployment, David Carter Cornett

Masters Theses

The deep learning technique of convolutional neural networks (CNNs) has greatly advanced the state-of-the-art for computer vision tasks such as image classification and object detection. These solutions rely on large systems leveraging wattage-hungry GPUs to provide the computational power to achieve such performance. However, the size, weight and power (SWaP) requirements of these conventional GPU-based deep learning systems are not suitable when a solution requires deployment to so called "Edge" environments such as autonomous vehicles, unmanned aerial vehicles (UAVs) and smart security cameras.

The objective of this work is to benchmark FPGA-based alternatives to conventional GPU systems that have the ...


Deep Learning Based Prediction Of Clogging Occurrences During Lignocellulosic Biomass Feeding In Screw Conveyors, Yang Li Dec 2021

Deep Learning Based Prediction Of Clogging Occurrences During Lignocellulosic Biomass Feeding In Screw Conveyors, Yang Li

Masters Theses

Over the last decades, there have been substantial government and private sector investments to establish a commercial biorefining industry that uses lignocellulosic biomass as feedstock to produce fuels, chemicals, and other products. However, several biorefining plants experienced material conveyance problems due to the variability and complexity of the biomass feedstock. While the problems were reported in most conveyance unit operations in the biorefining plants, screw conveyors merit special attention because they are the most common conveyors used in biomass conveyance and typically function as the last conveyance unit connected to the conversion reactors. Thus, their operating status affects the plant ...


Investigation Of The Rupture Initiation And Mechanical Performance Of Alumina Port Covers For Integrated Rocket Ramjet Systems, Haley R. Goldston Dec 2021

Investigation Of The Rupture Initiation And Mechanical Performance Of Alumina Port Covers For Integrated Rocket Ramjet Systems, Haley R. Goldston

Masters Theses

Hypersonic flight is widely considered essential to ensure a competitive defensive capability in the United States. In hypersonic air breathing propulsion, cruise vehicles are a priority research and development area given the ease to which they can be implemented with existing DoD infrastructure. Advancements in ramjet engine systems, including integrated rocket ramjets, play a considerable role in military and space access hypersonic vehicle designs. By design, ramjets cannot produce static thrust. They first need to be brought to operational speeds with the help of a rocket booster. An integrated rocket ramjet (IRR) combines the booster phase and the ramjet phase ...


Partial Discharge Testing And Detection Under Pwm Voltage, John Meadors Dec 2021

Partial Discharge Testing And Detection Under Pwm Voltage, John Meadors

Masters Theses

Partial Discharge detection and measurement is an important part of electric insulation design. However, in PWM (pulse width modulation) voltage source converter environments, the noise resulting from switching voltage (rise and fall times of tens of nanoseconds) makes detection and extraction of partial discharge difficult. Unique methods of partial discharge detection are needed to address and decouple the noise from partial discharge measurements. PWM voltage can feature high switching speeds and high dv/dt during voltage switching. These PWM voltage behaviors are not found in traditional utility high voltage applications, and the effects that this type of voltage has on ...


Thermodynamic Analysis Of An Autogenous Pressurization System, Samuel H. Smith Dec 2021

Thermodynamic Analysis Of An Autogenous Pressurization System, Samuel H. Smith

Masters Theses

Pressurized gas feed systems have been vital to spacecraft where a pump-fed design would prove too large, heavy, or complicated to be effective. This project investigates autogenous pressurization – a pressurized feed system where the intentional vaporization of liquid propellant to fill the ever-increasing ullage space with its own warm, low-density gas. Motivation for this research originates from the University of Tennessee Space Institute’s (UTSI) contract with Gloyer-Taylor Laboratories (GTL) to assist the development of an innovative pressurization system.

While other pressurization systems have been studied and used extensively, modeling of an autogenous system is less established. Despite the relative ...


Standardized 1x6u Cubesat Structure Design, Maximilian H. Brummel Nov 2021

Standardized 1x6u Cubesat Structure Design, Maximilian H. Brummel

Masters Theses

A CubeSat is a small satellite composed of one or more 10cm x 10cm x ~10cm cubes. Sometimes referred to as a “U” as in unit, the cubes can be combined in configurations of 2U, 3U, 6U, and more. CubeSats provide many advantages that larger satellites cannot offer. They are relatively inexpensive and can be fabricated much faster. Small-scale projects that require a fast timeline from conception up to completion are perfect for CubeSats. Furthermore, educational programs use CubeSat projects to teach and prepare students for the satellite industry. Popular configurations for CubeSat are 1U, 3U and 6U where the ...


Design And Testing Of A Foundation Raised Oscillating Surge Wave Energy Converter, Jacob R. Davis Oct 2021

Design And Testing Of A Foundation Raised Oscillating Surge Wave Energy Converter, Jacob R. Davis

Masters Theses

Our oceans contain tremendous resource potential in the form of mechanical energy. With the ability to capture and convert the energy carried in surface waves into usable electricity, wave energy converters (WECs) have been a long-held aspiration in ocean renewable energy. One of the most popular wave energy design concepts is the Oscillating Surge Wave Energy Converter (OSWEC). True to their namesake, OSWECs extract energy from the surge force induced by incident waves. In their most basic form, OSWECs are analogous to a bottom-hinged paddle which pitches fore and aft in the direction of wave motion. Most commonly, OSWECs are ...


Robustness Of Supply Chain Synchronization Strategies, Andrew Frere Oct 2021

Robustness Of Supply Chain Synchronization Strategies, Andrew Frere

Masters Theses

Modern manufacturing systems dealing with complex assemblies with large numbers of parts present particular challenges in the realm of supply chain management. Complex assemblies, such as those found in aerospace and automobile manufacturing, require thousands of parts to come together at the right time for final assembly. The large number of parts, often coming from hundreds of suppliers, combined with unreliable delivery times and high cost of many of these components can lead to incredibly high inventory costs and assembly delays. Typically, variable delays in part delivery are compensated for by either keeping a buffer of safety stock or a ...


Comparing And Improving The Design Of Physical Activity Data Visualizations, Peter M. Frackleton Oct 2021

Comparing And Improving The Design Of Physical Activity Data Visualizations, Peter M. Frackleton

Masters Theses

Heart disease is a leading cause of death in the United States, and older adults are at highest risk of being diagnosed with heart disease. Consistent physical exercise is an effective means of deterring onset of heart disease, and physical activity tracking devices can inspire greater activity in older adults. However, physical activity tracking device abandonment is quite common due to limitations on what can be learned from the activity data that is collected. Better data visualization of physical data presents an opportunity to surpass these limitations. In this thesis, a task-based human subject study was performed with three different ...


Modeling And Characterization Of Optical Metasurfaces, Mahsa Torfeh Oct 2021

Modeling And Characterization Of Optical Metasurfaces, Mahsa Torfeh

Masters Theses

Metasurfaces are arrays of subwavelength meta-atoms that shape waves in a compact and planar form factor. During recent years, metasurfaces have gained a lot of attention due to their compact form factor, easy integration with other devices, multi functionality and straightforward fabrication using conventional CMOS techniques. To provide and evaluate an efficient metasurface, an optimized design, high resolution fabrication and accurate measurement is required. Analysis and design of metasurfaces require accurate methods for modeling their interactions with waves. Conventional modeling techniques assume that metasurfaces are locally periodic structures excited by plane waves, restricting their applicability to gradually varying metasurfaces that ...


Action : Adaptive Cache Block Migration In Distributed Cache Architectures, Chandra Sekhar Mummidi Oct 2021

Action : Adaptive Cache Block Migration In Distributed Cache Architectures, Chandra Sekhar Mummidi

Masters Theses

Increasing number of cores in chip multiprocessors (CMP) result in increasing traffic to last-level cache (LLC). Without commensurate increase in LLC bandwidth, such traffic cannot be sustained resulting in loss of performance. Further, as the number of cores increases, it is necessary to scale up the LLC size; otherwise, the LLC miss rate will rise, resulting in a loss of performance. Unfortunately, for a unified LLC with uniform cache access time, access latency increases with cache size, resulting in performance loss. Previously, researchers have proposed partitioning the cache into multiple smaller caches interconnected by a communication network which increases aggregate ...


Benchmarking Small-Dataset Structure-Activity-Relationship Models For Prediction Of Wnt Signaling Inhibition, Mahtab Kokabi Oct 2021

Benchmarking Small-Dataset Structure-Activity-Relationship Models For Prediction Of Wnt Signaling Inhibition, Mahtab Kokabi

Masters Theses

Quantitative structure-activity relationship (QSAR) models based on machine learning algorithms are powerful tools to expedite drug discovery processes and therapeutics development. Given the cost in acquiring large-sized training datasets, it is useful to examine if QSAR analysis can reasonably predict drug activity with only a small-sized dataset (size < 100) and benchmark these small-dataset QSAR models in application-specific studies. To this end, here we present a systematic benchmarking study on small-dataset QSAR models built for prediction of effective Wnt signaling inhibitors, which are essential to therapeutics development in prevalent human diseases (e.g., cancer). Specifically, we examined a total of 72 two-dimensional (2D) QSAR models based on 4 best-performing algorithms, 6 commonly used molecular fingerprints, and 3 typical fingerprint lengths. We trained these models using a training dataset (56 compounds), benchmarked their performance on 4 figures-of-merit (FOMs), and examined their prediction accuracy using an external validation dataset (14 compounds). Our data show that the model performance is maximized when: 1) molecular fingerprints are selected to provide sufficient, unique, and not overly detailed representations of the chemical structures of drug compounds; 2) algorithms are selected to reduce the number of false predictions due to class imbalance in the dataset; and 3) models are selected to reach balanced performance on all 4 FOMs. These results may provide general guidelines in developing high-performance small-dataset QSAR models for drug activity prediction.


Internet Infrastructures For Large Scale Emulation With Efficient Hw/Sw Co-Design, Aiden K. Gula Oct 2021

Internet Infrastructures For Large Scale Emulation With Efficient Hw/Sw Co-Design, Aiden K. Gula

Masters Theses

Connected systems are becoming more ingrained in our daily lives with the advent of cloud computing, the Internet of Things (IoT), and artificial intelligence. As technology progresses, we expect the number of networked systems to rise along with their complexity. As these systems become abstruse, it becomes paramount to understand their interactions and nuances. In particular, Mobile Ad hoc Networks (MANET) and swarm communication systems exhibit added complexity due to a multitude of environmental and physical conditions. Testing these types of systems is challenging and incurs high engineering and deployment costs. In this work, we propose a scalable MANET emulation ...


Metabolic Modeling Of Cystic Fibrosis Airway Microbiota From Patient Samples, Arsh Vyas Oct 2021

Metabolic Modeling Of Cystic Fibrosis Airway Microbiota From Patient Samples, Arsh Vyas

Masters Theses

Cystic Fibrosis (CF) is a genetic disorder, found with higher prevalence in the Caucasian population, affecting > 30,000 individuals in the United States and > 70,000 worldwide. Due to the astoundingly high rate of mortality among CF patients being attributed to respiratory failure brought on by chronic bacterial infections and subsequent airway inflammation, there has been a lot of focus on systematically analyzing CF lung airway communities. While it is observed traditionally that Pseudomonas aeruginosa is the most threatening and persistent CF colonizer due to high antibiotic resistance, recent studies have elicited the roles of other pathogens and it has ...


Synthesis Of Functionalized Acrylic Nanoparticles As A Precursor To Bifunctional Colloids, Guinevere E. Tillinghast Oct 2021

Synthesis Of Functionalized Acrylic Nanoparticles As A Precursor To Bifunctional Colloids, Guinevere E. Tillinghast

Masters Theses

Water-borne coatings have increased in popularity due to the recent environmental regulations being placed on coating formulation. The most readily available coatings without volatile organic compounds are thermoplastic polymer dispersions that rely on interdiffusion to form a film. These dispersions are reliant on toxic crosslinking chemistries to achieve adequate coating mechanical properties, but still have significantly inferior properties when compared with current thermosetting industrial coatings that contain volatile organic compounds. As a result, waterborne coatings made with conventional emulsion polymers cannot be considered for high-performance coatings. Polyurethane dispersions have been developed that can meet these demands, but require several lengthy ...


Spatiotemporal Metabolic Modeling Of Pseudomonas Aeruginosa Biofilm Expansion, Robert Sourk Oct 2021

Spatiotemporal Metabolic Modeling Of Pseudomonas Aeruginosa Biofilm Expansion, Robert Sourk

Masters Theses

Spatiotemporal metabolic modeling of microbial metabolism is a step closer to achieving higher dimensionalities in numerical studies (in silico) of biofilm maturation. Dynamic Flux Balance Analysis (DFBA) is an advanced modeling technique because this method incorporates Genome Scale Metabolic Modeling (GSMM) to compute the biomass growth rate and metabolite fluxes. Biofilm thickness is pertinent because this variable of biofilm maturation can be measured in a laboratory (in vitro). Pseudomonas aeruginosa (P. aeruginosa) is the model bacterium used in this computational model based on previous research conducted by Dr. Michael Henson, available GSMMs, and the societal significance of patients suffering from ...


Effect Of Phase Composition Of Tungsten Carbide On Its Catalytic Activity For Toluene Hydrogenation, Aditya Rane Oct 2021

Effect Of Phase Composition Of Tungsten Carbide On Its Catalytic Activity For Toluene Hydrogenation, Aditya Rane

Masters Theses

Commercially important hydrogenation reactions make use of precious noble metal catalysts which are becoming increasingly scarce, and the search for capable alternative catalysts prevails. Transition metal carbides of group IV-VI metals show similar catalytic behavior to platinum and are $103/kg lower in price than the precious metal catalysts. Tungsten carbide, studied in this work, can form in different stoichiometries and phase compositions depending upon synthesis methods. Synthesis of high surface area tungsten carbide with control over its phase composition remains a challenge currently. In this work, the novel isothermal synthesis method of tungsten carbide (WC, W2C) in a CH4 ...


Metabolic Modeling Of Bacterial Co-Cultures For Co-To-Butyrate Conversion In Bubble Column Bioreactors, Naresh Kandlapalli Oct 2021

Metabolic Modeling Of Bacterial Co-Cultures For Co-To-Butyrate Conversion In Bubble Column Bioreactors, Naresh Kandlapalli

Masters Theses

One of the most promising routes to renewable liquid fuels and chemicals is the fermentation of waste carbon by specialized microbes. Commercial development of gas fermentation technology is underway but many fundamental research problems must be addressed to further advance the technology towards economic competitiveness. This thesis addresses the important problem of developing integrated metabolic and transport models that predict gas fermentation performance in industrially relevant bubble column reactors. The computational models describe the conversion of CO-rich waste streams including synthesis gas to the platform chemical butyrate. The proposed modeling approach involves combining genome-scale reconstructions of bacterial species metabolism with ...


Synthesis Of Hybrid Inorganic-Organic Microparticles, Shreyas Joshi Oct 2021

Synthesis Of Hybrid Inorganic-Organic Microparticles, Shreyas Joshi

Masters Theses

The self-assembly of isotropic and anisotropic colloidal particles into higher-ordered structures has been of great interest recently due to the promise of creating metamaterials with novel macroscopic properties. The physicochemical properties of these metamaterials can be tailored to achieve composites with tunable functionalities. The formation of these metamaterials can be used as a pathway to emulating advanced biological systems. In particular, synthetically mimicking the surface of a moth’s eye, which consists of arrays of ellipsoidal protuberances, can be used as a strategy for fabricating antireflective coatings.

To enable this technology, it is necessary to design a synthesis scheme that ...


Free Radical Polymerization Of Novel Copolymer; Ethylene-Co-Diethyl Methylene Malonate Copolymers, Sydney Foster Oct 2021

Free Radical Polymerization Of Novel Copolymer; Ethylene-Co-Diethyl Methylene Malonate Copolymers, Sydney Foster

Masters Theses

Ethylene copolymers are widely used as packaging materials, adhesives and specialty polymers for well-regarded cost savings, durability, chemical resistance, and hot melt character. This work examines the use of diester monomers known as malonates to determine the plausibility of utilizing an uncommon monomer class for producing novel ethylene copolymers. Ethylene is copolymerized with diethyl methylene malonate—a simple malonate representative of more complex and highly modified malonate monomers and macromers—to produce ethylene-co-diethyl methylene malonate in a range of molecular weights. Ethylene-co-diethyl methylene malonate is analyzed to determine physical properties such as glass transition temperature, chain length and monomer incorporation ...


Visuomotor Adaptation During Asymmetric Walking, Charles Napoli Oct 2021

Visuomotor Adaptation During Asymmetric Walking, Charles Napoli

Masters Theses

Necessary for effective ambulation, head stability affords optimal conditions for the perception of visual information during dynamic tasks. This maintenance of head-in-space equilibrium is achieved, in part, by the attenuation of the high frequency impact shock resulting from ground contact. While a great deal of experimentation has been done on the matter during steady state locomotion, little is known about how head stability or dynamic visual acuity is maintained during asymmetric walking.

In this study, fifteen participants were instructed to walk on a split-belt treadmill for ten minutes while verbally reporting the orientation of a randomized Landolt-C optotype that was ...