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Full-Text Articles in Engineering

Reconfiguration-Driven Assembly Of Inorganic Nanomembranes, Divya Jyoti Prakash May 2025

Reconfiguration-Driven Assembly Of Inorganic Nanomembranes, Divya Jyoti Prakash

Chemical and Biological Engineering ETDs

This thesis focuses on the guided self-assembly of metastable nanomembranes (NMs) that are either amorphous or polycrystalline. Guided self-assembly of NMs is a robust and scalable method to obtain a variety of three-dimensional structures such as helices, rolled-up tubes, and networks of interconnected channels. These 3D structures have important applications as on-chip actuators, sensors, inductors, transformers, waveguides, and antennas. Furthermore, a large amount of strain and strain gradient can be imparted in NMs by bending them to a nanoscale and microscale radius of curvature, making guided self-assembly on NMs a viable route to extreme strain engineering of amorphous and polycrystalline …


Hitch Cart “Landing Gear”, Rebekah White, Jose Raygoza, Randy Hernandez, Brandon Leon Dec 2024

Hitch Cart “Landing Gear”, Rebekah White, Jose Raygoza, Randy Hernandez, Brandon Leon

Mechanical Engineering

This report aims to allow our sponsor, to review our design process of the Hitch Cart Landing Gear Prototype. In the design overview section of this report, we discuss the primary design modifications we made to the wheel mechanism of the existing hitch cart prototype, including the addition of the ACME screws and the folding brackets. This allows our sponsor to see the intended improvements made to the past prototype and understand the primary goal of our project. Then, in the implementation section, we cover the entire manufacturing process to allow our sponsor to understand what manufacturing steps must be …


Shape Memory Alloy Capsule Micropump For Drug Delivery Applications, Youssef Mohamed Kotb Jun 2024

Shape Memory Alloy Capsule Micropump For Drug Delivery Applications, Youssef Mohamed Kotb

Theses and Dissertations

Implantable drug delivery devices have many benefits over traditional drug administration techniques and have attracted a lot of attention in recent years. By delivering the medication directly to the tissue, they enable the use of larger localized concentrations, enhancing the efficacy of the treatment. Passive-release drug delivery systems, one of the various ways to provide medication, are great inventions. However, they cannot dispense the medication on demand since they are nonprogrammable. Therefore, active actuators are more advantageous in delivery applications. Smart material actuators, however, have greatly increased in popularity for manufacturing wearable and implantable micropumps due to their high energy …


Design Of High Efficiency Doherty Power Amplifier, Kobi G. Kelly, Severin Pindell Jun 2024

Design Of High Efficiency Doherty Power Amplifier, Kobi G. Kelly, Severin Pindell

Electrical Engineering

The project includes design and fabrication of a high efficiency power amplifier for a student design competition held at International Microwave Symposium (IMS) 2023. Efficient power amplifiers are critical for base station communication requiring efficient use of available power. The final design optimizes power added efficiency (PAE) and linearity. The amplifier will operate at 2.45 GHz. Competitive PAE above 50%, and C/I above 30 dB is achieved by leveraging a Doherty class amplifier using accurate discrete CGH4006P transistor models to simulate an efficient and linear design. Unique design features include optimal transistor bias point selection and power split ratios between …


A Comprehensive Review Of Fischer-Tropsch Synthesis Processes To Produce Sustainable Diesel And Aviation Fuel, Joseph C. Steinagel May 2024

A Comprehensive Review Of Fischer-Tropsch Synthesis Processes To Produce Sustainable Diesel And Aviation Fuel, Joseph C. Steinagel

Honors College Theses

The greatest threat known to humankind today is global warming. It affects every nation on the planet and the natural order of all living things. Consequently, this ongoing crisis necessitates action to scientifically revolutionize important areas of society, including researching modern adaptations of the transportation industry. In that regard, it has been determined that an effective short-term answer to eliminating carbon emissions is to produce sustainable fuels that run cooperatively with the well-established machines of today. Sustainable aviation fuel (SAF) is one such topic of interest, and the Fischer-Tropsch synthesis process is an effective way of producing SAF. To that …


Effect Of Waste Covid-19 Masks On Compaction Characteristics Of Silty-Clay Soil, Sydney K. Lawson May 2024

Effect Of Waste Covid-19 Masks On Compaction Characteristics Of Silty-Clay Soil, Sydney K. Lawson

Honors College Theses

The present study aims to explore the effect of adding shredded waste Covid-19 masks to silty-clay soil on the soil’s compaction characteristics for beneficial use in embankment, the subgrade of roadways, or backfill. This was accomplished by using two different types of masks: blue surgical masks and KN95 masks. Both mask types were hand shredded into half-inch sections using safety-scissors. The maximum dry density (MDD) and optimum moisture content (OMC) are the two most important compaction characteristics, and they were determined by the Standard Proctor Compaction Test (ASTM D698 / AASHTO T99). The change of both the MDD and OMC …


Analyzing Heat Generated From Electro-Osmotic Flow Utilizing Computational Fluid Dynamics, Jordan Elizabeth Grothe May 2024

Analyzing Heat Generated From Electro-Osmotic Flow Utilizing Computational Fluid Dynamics, Jordan Elizabeth Grothe

Honors Thesis

Without extensive vascularization, the transfer of fluid and nutrients through human tissue is limited to diffusion and weak interstitial flow. Electroosmosis, or the flow of fluid driven by an electrical field, has become a promising solution. Scientists have begun applying electricity to human tissue to promote stronger interstitial flow; however, optimization of this process has proven to be a challenge due to ohmic heating. Cells function within a small range of temperatures and exposure to voltages exceeding the threshold will cause cells to degrade and die prematurely. This research seeks to better understand and quantify the range of voltage where …


Physical And Stochiometric Controls On Nutrient Uptake And Ecosystem Respiration In Contrasting Sites, Jancoba K. Dorley May 2024

Physical And Stochiometric Controls On Nutrient Uptake And Ecosystem Respiration In Contrasting Sites, Jancoba K. Dorley

Civil Engineering ETDs

Meteorological, hydrological, and biogeochemical processes naturally control stream ecosystems. These processes define the frequency and distribution of precipitation and the supply and demand of solutes and particles to support aquatic food chains through space and time. Studies have also found that stream ecosystems are also controlled by anthropogenic activities, which occur on a much shorter timescale. These anthropogenic activities affect stream ecosystems' structure and function from local to planetary changes to the environment. It is essential for scientists and engineers to understand the relationships between naturally occurring processes and those created by human activities for a better interpretation of stream …


Cignn: Community-Induced Graph Neural Networks, Shi Yin Hong May 2024

Cignn: Community-Induced Graph Neural Networks, Shi Yin Hong

Computer Science and Computer Engineering Undergraduate Honors Theses

Message-passing graph neural networks (MPGNNs) are known to have limitations in their representational power. Recent work proposes subgraph graph neural network (subgraph GNN) models to address these limitations by upgrading the local node representations of MPGNNs to respective subgraph representations. However, existing subgraph GNN models have limited interpretability in capturing inherent local structural dynamics across diverse graph structures. In this work, we present a novel subgraph GNNs framework, termed Community-Induced Graph Neural Network (CiGNN). The key idea of CiGNN is to endow an intuitive interpretability basis for subgraph GNNs by capturing the dynamics of inherent structural community topology in subgraph …


Advancing Near Surface Soil Moisture Measurements Using Robotics, Automation, And Remote Sensing, Hemanth Narayan Dakshinamurthy May 2024

Advancing Near Surface Soil Moisture Measurements Using Robotics, Automation, And Remote Sensing, Hemanth Narayan Dakshinamurthy

All Graduate Theses and Dissertations, Fall 2023 to Present

Near-surface soil moisture, or the water content within the soil, is important for understanding the interactions between land and the atmosphere, and for monitoring plants in agricultural settings. However, soil moisture can be highly variable within the same field and varies considerably with time. The challenge involved with measuring soil moisture is that traditional techniques that rely on obtaining large samples are labor and time-intensive, especially for large fields. Developments in sensor technologies have allowed users to record the soil moisture regularly at the points where the sensors are installed. However, to understand how soil moisture changes across a field …


Cam And Design For Manufacturing: Developing A Project-Based Learning Course, Stephen Pierson May 2024

Cam And Design For Manufacturing: Developing A Project-Based Learning Course, Stephen Pierson

Mechanical Engineering Undergraduate Honors Theses

To effectively serve student career success, mechanical engineering programs must teach students how to account for manufacturing considerations in design. Despite this, manufacturing education is a glaring area of need in current engineering curricula. In fact, basic manufacturing knowledge is one of the only hard skills consistently ranked as one of the greatest weaknesses of mechanical engineering hires in surveys of industrial employers over the last few decades. Without radically changing departmental curriculum to include more emphasis on design-build projects, one solution to combat this is to incubate a lab course in mechanical engineering programs in which undergraduates would practice …


The Analysis Of Mechanical Exfoliation Of Graphene For Various Fabrication And Automation Techniques, Lance Yarbrough May 2024

The Analysis Of Mechanical Exfoliation Of Graphene For Various Fabrication And Automation Techniques, Lance Yarbrough

Mechanical Engineering Undergraduate Honors Theses

Mechanical Exfoliation of Graphene is an often-overlooked portion of the fabrication of quantum devices, and to create more devices quickly, optimizing this process to generate better flakes is critical. In addition, it would be valuable to simulate test pulls quickly, to gain insight on flake quality of various materials and exfoliation conditions. Physical pulls of graphene at various temperatures, pull forces, and pull repetitions were analyzed and compared to the results of ANSYS simulations, solved for similar results. Using ANSYS’ ability to predict trends in exfoliations, flake thickness and coverage using stress and deflection analyses were investigated. Generally, both strongly …


A Smart Hybrid Enhanced Recommendation And Personalization Algorithm Using Machine Learning, Aswin Kumar Nalluri May 2024

A Smart Hybrid Enhanced Recommendation And Personalization Algorithm Using Machine Learning, Aswin Kumar Nalluri

Electronic Theses, Projects, and Dissertations

In today’s age of streaming services, the effectiveness and precision of recommendation systems are crucial in improving user satisfaction. This project introduces the Smart Hybrid Enhanced Recommendation and Personalization Algorithm (SHERPA) a cutting-edge machine learning approach aimed at transforming how movie suggestions are made. By combining Term Frequency Inverse Document Frequency (TF-IDF) for content based filtering and Alternating Squares (ALS) with Weighted Regularization for filtering SHERPA offers a sophisticated method for delivering tailored recommendations.

The algorithm underwent evaluation using a dataset that included over 50 million ratings from 480,000 Netflix users encompassing 17,000 movie titles. The performance of SHERPA was …


Development And Testing Of An 8-Bit Digitally Throttled Hybrid Rocket Motor, Trevor W. Coombs May 2024

Development And Testing Of An 8-Bit Digitally Throttled Hybrid Rocket Motor, Trevor W. Coombs

All Graduate Theses and Dissertations, Fall 2023 to Present

Hybrid rocket motors that use a solid fuel grain and liquid oxidizer are low-cost and safer alternatives to traditional rocket motors. Another benefit of hybrid rocket motors is that during a burn, the amount of oxidizer into the combustion chamber can be changed, this capability is called throttling. To take advantage of the throttling ability of hybrid rocket motors, a throttling valve made up of 8 individually controlled valves is designed, developed, and tested, which is documented in this thesis. The results of the testing campaign show that the 8-bit digital throttling valve technology is an effective throttling technology and …


Field Flow Measurements For Pipe Installations With Non-Ideal Conditions, Jake Douglas May 2024

Field Flow Measurements For Pipe Installations With Non-Ideal Conditions, Jake Douglas

All Graduate Theses and Dissertations, Fall 2023 to Present

Accurate flow measurement data is necessary to effectively manage water resources. The purpose of this research is to investigate options to improve field flow measurement by investigating alternatives for calibrating flow meters installed in non-ideal piping. Typically, to accurately measure a flow rate using most types of flow meters, it is recommended that a straight section of pipe be installed immediately upstream and downstream of the flow meter to avoid flow fluctuations at the meter location. However, in many cases, flow disturbances upstream of the meter are unavoidable.

The performance of field flow measurements in non-ideal piping scenarios were studied …


Understanding Peer Interactions In Undergraduate Engineering Education, Jack C. Elliott May 2024

Understanding Peer Interactions In Undergraduate Engineering Education, Jack C. Elliott

All Graduate Theses and Dissertations, Fall 2023 to Present

Whether they occur inside or outside the classroom, social interactions between undergraduate students play a key role in student success. As a result, engineering education researchers have sought to understand why students interact with certain peers, and which types of interactions relate to positive student outcomes. While existing studies show promising results for formal group assignments, most have been conducted in a single undergraduate course. Because important student interactions occur outside and inside courses, more research is needed to fully understand (a) why students choose to, or not to, interact with other students, and (b) how these interactions relate to …


Mechanical Properties And Microstructure Of Multi-Materials Fabricated Through A Combination Of Lpbf And Ded Additive Manufacturing Techniques, Christopher J. Bettencourt May 2024

Mechanical Properties And Microstructure Of Multi-Materials Fabricated Through A Combination Of Lpbf And Ded Additive Manufacturing Techniques, Christopher J. Bettencourt

All Graduate Theses and Dissertations, Fall 2023 to Present

This research explores the use of different metals combined through 3D-printing to enhance the performance of materials, with a focus on making heat exchangers more cost-effective for renewable energy. The goal is to replace a costly high-temperature alloy with a more affordable low-temperature alloy, using metal additive manufacturing for its benefits such as less material waste, faster production, reduced weight, and the ability to print entire assemblies in one go. The study delves into a unique combination of two 3D-printing techniques, Directed Energy Deposition and Laser Powder-Bed Fusion, to create a multi-material composed of stainless steel 316L and a nickel-based …


Tracking Perfluoroalkyl Substances From Wastewater Influent To Its Accumulation In Vegetables And Forage Grass, Simon Kozik May 2024

Tracking Perfluoroalkyl Substances From Wastewater Influent To Its Accumulation In Vegetables And Forage Grass, Simon Kozik

All Graduate Theses and Dissertations, Fall 2023 to Present

Per and poly-fluorinated alkyl substances (PFAS) are a class of chemicals that are persistent in the environment. PFAS was found in wastewater, which can be used after wastewater treatment for irrigation water, and in the biosolids that can be mixed with soils to provide nutrients and generally improve soil quality. This study found when wastewater was used it increases the level of PFAS in vegetables and forage grass. PFAS concentrations were tracked from the influent of the wastewater treatment plant to the effluent, to the irrigation water, to the soil, and finally into the vegetable and forage grass grown on …


Uv-A Light: A Novel Method For Food Dehydration, Mckade S. Roberts May 2024

Uv-A Light: A Novel Method For Food Dehydration, Mckade S. Roberts

All Graduate Theses and Dissertations, Fall 2023 to Present

Dehydration is one of the most prevalent forms of food preservation, with approximately 85% of food is hot air drying due to the simplicity of the process. The high temperatures employed in this method may also induce a loss in nutritional quality, which involves destruction of micronutrients (vitamins), and loss of color.

The aim of this work is to develop a low energy, non-thermal method of food dehydration that results in a high-quality product through the application of Ultraviolet light, within the UV-A range. UV light can be separated into its 3 categories based on the wavelength of light from …


Water Data Science: Data Driven Techniques, Training, And Tools For Improved Management Of High Frequency Water Resources Data, Amber Spackman Jones May 2024

Water Data Science: Data Driven Techniques, Training, And Tools For Improved Management Of High Frequency Water Resources Data, Amber Spackman Jones

All Graduate Theses and Dissertations, Fall 2023 to Present

Electronic sensors can measure water and climate conditions at high frequency and generate large quantities of observed data. This work addresses data management challenges associated with the volume and complexity of high frequency water data. We developed techniques for automatically reviewing data, created materials for training water data managers, and explored existing and emerging technologies for sensor data management.

Data collected by sensors often include errors due to sensor failure or environmental conditions that need to be removed, labeled, or corrected before the data can be used for analysis. Manual review and correction of these data can be tedious and …


Exploring The Role Of Near Channel Geospatial Attributes To Predict Suspended Sediment Concentration Patterns Across The Conus Region, Aaron J. Sigman May 2024

Exploring The Role Of Near Channel Geospatial Attributes To Predict Suspended Sediment Concentration Patterns Across The Conus Region, Aaron J. Sigman

All Graduate Theses and Dissertations, Fall 2023 to Present

High concentrations of suspended sediment (SSC) in a river can represent a critical water quality concern, reduce the storage capacity of reservoirs, and impact aquatic habitat. The total amount of sediment is calculated from a combination of river properties, including the amount of available sediment and the flow of water carrying the sediment. Water flow properties can be found using local information about the channel, however understanding the concentration of sediment in the river requires understanding the supply of sediment from the watershed. To understand where sediment is coming from, we examined over 1000 United States Geological Survey sites with …


Mathematical Modeling For Dental Decay Prevention In Children And Adolescents, Mahdiyeh Soltaninejad Apr 2024

Mathematical Modeling For Dental Decay Prevention In Children And Adolescents, Mahdiyeh Soltaninejad

Dissertations

The high prevalence of dental caries among children and adolescents, especially those from lower socio-economic backgrounds, is a significant nationwide health concern. Early prevention, such as dental sealants and fluoride varnish (FV), is essential, but access to this care remains limited and disparate. In this research, a national dataset is utilized to assess sealants' reach and effectiveness in preventing tooth decay, particularly focusing on 2nd molars that emerge during early adolescence, a current gap in the knowledge base. FV is recommended to be delivered during medical well-child visits to children who are not seeing a dentist. Challenges and facilitators in …


Faa Medical Reform, Dana Rose Apr 2024

Faa Medical Reform, Dana Rose

Honors Projects

This project investigates the challenges and implications of obtaining medical certification for pilots with a history of childhood misdiagnoses, focusing on Attention-Deficit/Hyperactivity Disorder (ADHD). Misdiagnoses in childhood can lead to significant obstacles in the aviation industry's medical certification process, posing unique hurdles for aspiring pilots. The study examines the current FAA guidelines and procedures for medical certification, particularly the evaluation requirements for individuals with ADHD. It also explores common challenges faced by pilots, the effects of childhood misdiagnoses on their eligibility, and the impact of the FAA's ADHD evaluation process.

Through interviews with Aviation Medical Examiners (AMEs), this project identifies …


Tunable Dual-Phase Dual-Drug Delivery System Using A Plga Microparticle/Pva Hydrogel Composite, Timothy John Eck Apr 2024

Tunable Dual-Phase Dual-Drug Delivery System Using A Plga Microparticle/Pva Hydrogel Composite, Timothy John Eck

Theses and Dissertations

Current drug-eluting coatings have demonstrated controlled long-term, sustained release but have only tried to mitigate short-term burst release as a negative side effect. For applications like wound healing, there is a need for a drug-eluting coating which is adjustable in both short- and long-term release, independent of each other. We present a tunable dual-phase dual-drug delivery coating composed of drug-loaded polymer microparticles and drug-loaded hydrogel which can control short term and long term release individually in this study. This coating was created using lidocaine and dexamethasone encapsulated in poly(D,L-lactide-co-glycolide) particles combined with lidocaine- and dexamethasone-loaded poly(vinyl alcohol) hydrogel. Hydrogel drug …


Modified Coulomb Approach For Squat Silos, Mitchell Cade South Apr 2024

Modified Coulomb Approach For Squat Silos, Mitchell Cade South

Theses and Dissertations

Traditional methods for calculating lateral pressures in silos, such as Janssen's Method and Coulomb's Method, have limitations due to the underlying assumptions of each methodology. This research investigates an approach which adapts Coulomb's Method to account for the cylindrical geometry of silos. The Silo Wedge Method (SWM) distinguishes between two cases based on the aspect ratio (height/diameter) of the silo. Comparative analysis reveals that the SWM accurately matches Coulomb's Method for linear retaining walls when the silo aspect ratio approaches zero. As the aspect ratio increases above 0.25, the SWM exhibits behavior similar to Janssen's Method. This suggests a potential …


A Hybrid Communication System Using 5g Cellular And Ads-B For Uavs In High-Density Airspaces, Coulton Lee Karch Apr 2024

A Hybrid Communication System Using 5g Cellular And Ads-B For Uavs In High-Density Airspaces, Coulton Lee Karch

Theses and Dissertations

Robust communication is required to provide a safe airspace for the large numbers of unmanned aerial systems that are coming to the National Airspace System (NAS). This thesis explores methods for providing robust communication to large numbers of vehicles in the NAS. Automatic dependent surveillance-broadcast (ASD-B) is a transmission system that can transmit to and is currently required on all manned aircraft. Unfortunately, ADS-B suffers connectivity problems when supporting large numbers of unmanned aerial systems (UAS). The 5G Cellular protocol can support large numbers of UAS, but connectivity suffers with an increase in distance and interference. Using a 5G cellular …


Systems, Models, And Simulation For Novel Microfabrication Of Silicon Carbide And Metal Mesh Filters, Hunter R. J. Stevenson Apr 2024

Systems, Models, And Simulation For Novel Microfabrication Of Silicon Carbide And Metal Mesh Filters, Hunter R. J. Stevenson

Theses and Dissertations

As the boundaries of Moore's Law rapidly approach, research is increasingly turning to exotic materials and metamaterials to advance the capabilities of electronic and micromechanical systems. This thesis presents systems, models, and simulation techniques for novel microfabrication in the realms of silicon carbide (SiC) and metal mesh filters. Through the unification of femtosecond laser pulses, high numerical aperture (NA) objective lenses, and system power and motion control, a system capable of achieving arbitrary 3D features without line-of-sight with aspect ratios up to 109:1 in SiC is developed. Additionally, a model of a direct-write femtosecond-laser-ablation fabricated metal mesh filter (MMF) is …


Improving Wifi Sensor Network Security Through Unassociated Device Communication Using Wireless Latency Shift Keying, Jacob Edward Johnson Apr 2024

Improving Wifi Sensor Network Security Through Unassociated Device Communication Using Wireless Latency Shift Keying, Jacob Edward Johnson

Theses and Dissertations

IEEE 802.11 (WiFi) only has two modes of trust--complete trust or complete untrust. The lack of nuance leaves no room for sensors that a user does not fully trust, but wants to connect to their network, such as a WiFi sensor. Solutions exist, but they require advanced knowledge of network administration. We solve this problem by introducing a new way of modulating data in the latency of the network, called Latency Shift Keying. We use specific characteristics of the WiFi protocol to carefully control the latency of just one device on the network. We build a transmitter, receiver, and modulation …


Gps-Denied Localization Of Landing Evtol Aircraft, Aaron C. Brown Apr 2024

Gps-Denied Localization Of Landing Evtol Aircraft, Aaron C. Brown

Theses and Dissertations

This thesis presents a dedicated GPS-denied landing system designed for electric vertical takeoff and landing (eVTOL) aircraft. The system employs active fiducial light pattern localization (AFLPL), which provides highly accurate and reliable navigation during critical landing phases. AFLPL utilizes images of a constellation comprised of modulating infrared lights strategically positioned on the landing site, to determine the aircraft pose through the use of a perspective-n-point (PnP) solver. The AFLPL system underwent thorough development, enhancement, and implementation to address and demonstrate its potential in navigation and its inherent limitations. A proposed method addresses the limitations of AFLPL by using an extended …


Development Of Zr(Iv) Mof-Enabled Nerve Agent Electrochemical Hydrolysis Sensors, Tyler James Marlar Apr 2024

Development Of Zr(Iv) Mof-Enabled Nerve Agent Electrochemical Hydrolysis Sensors, Tyler James Marlar

Theses and Dissertations

Nerve agents are acetylcholinesterase inhibitors and among the most toxic chemical warfare agents ever synthesized. Detection of these chemicals is critical for the protection of populations and strategic resources. G-series nerve agents are volatile compounds. V-series nerve agents are persistent phosphonothioate compounds. Persistent nerve agents do not readily volatilize and can contaminate environmental resources for extended periods. While nerve agents are inherently non-electroactive, they can be hydrolyzed to electroactive products compatible with electrochemical sensing. Zr(IV) MOFs are next-generation nanoporous materials, which have been shown to rapidly catalyze nerve agent hydrolysis. In this work, the catalytic processes of MOF-808, a specific …