Engineering Commons^™

An Injectable Thermosensitive Biodegradable Hydrogel Embedded With Snap Containing Plla Microparticles For Sustained Nitric Oxide (No) Delivery For Wound Healing, Nikhil Mittal

Dissertations, Master's Theses and Master's Reports

After injury, wound healing is a complex sequential cascade of events essential for the proper recovery of the wound without the scar formation. Nitric oxide (NO) is a small, endogenous free-radical gas with antimicrobial, vasodilating and growth factor stimulating properties. NO has wide biomedical application especially in wound healing however, its usability is hindered due its administration problem as it is highly unstable.

In this work, poly (l-lactic acid) microparticles encapsulated with NO donor S-nitroso-N-acetyl-D-penicillamine (SNAP) were prepared using water-in-oil-water double emulsion solvent evaporation method for controlled delivery for NO at the specific site. The NO release from SNAP-PLLA microparticles …

Measurement Of Planar Fault Probabilities In Austempered Ductile Iron And 304l Stainless Steel, Nathan Peterson

Dissertations, Master's Theses and Master's Reports

During plastic deformation both stacking and twin faults can be generated in face-centered cubic materials, including iron-based metals that contain thermally stable austenite. These planar faults are a critical component of the austenite to martensite transformation, forming shear bands that can act as nucleation sites. The measurement of these faults via x-ray diffraction has been long established, however it has not been applied widely to austempered ductile irons. The ability to measure these faulting probabilities could give insights into the transformation as a function of deformation. In this work both planar fault densities were measured in austempered ductile iron to …

Commercialization Of The Carbon Nanotube Thermophone For Active Noise Control Applications, Steven A. Senczyszyn

Dissertations, Master's Theses and Master's Reports

The rate of commercialization for technology developed in junction with academic institutions has risen dramatically over the past 30 years. Since the introduction of the Bayh-Dole Act in 1980, the amount of intellectual property owned by academic institutions has increased exponentially, and with that, there has also been an increase in the number of university spinouts generated. However, the increase of spinouts does not match the rate of increase in intellectual property. The National Science Foundation has created the Innovation Corps (I-Corps) program to help bridge this gap and provide academic professionals and students the tools necessary to commercialize technology …

Resource Optimization In Wireless Sensor Networks For An Improved Field Coverage And Cooperative Target Tracking, Husam Sweidan

Dissertations, Master's Theses and Master's Reports

There are various challenges that face a wireless sensor network (WSN) that mainly originate from the limited resources a sensor node usually has. A sensor node often relies on a battery as a power supply which, due to its limited capacity, tends to shorten the life-time of the node and the network as a whole. Other challenges arise from the limited capabilities of the sensors/actuators a node is equipped with, leading to complication like a poor coverage of the event, or limited mobility in the environment. This dissertation deals with the coverage problem as well as the limited power and …

An Experimental And Computational Study Of Fuel Spray Interaction: Fundamentals And Engine Applications, Le Zhao

Dissertations, Master's Theses and Master's Reports

An efficient spray injection results in better vaporization and air-fuel mixing, leading to combustion stability and reduction of emissions in the internal combustion (IC) engines. The impingement of liquid fuels on chamber wall or piston surface in IC engines is a common phenomenon and fuel film formed in the spray-piston or cylinder wall impingement plays a critical role in engine performance and emissions. Therefore, the study of the spray impingement on the chamber wall or position surface is necessary.

To understand the spray-wall interaction, a single droplet impingement on a solid surface with different conditions was first examined. The droplet-wall …

Video Frame Reduction In Autonomous Vehicles, Gaurav R. Bagwe

Dissertations, Master's Theses and Master's Reports

Camera sensors are emerging in many applications such as Smart Buildings and autonomous driving. The Data generated by multiple cameras in a smart building and autonomous driving applications is usually transmitted through an edge box to a cloud terminal. This transmitted information requires a considerable channel bandwidth, which is not available through current communication standards. The report proposes a Camera Sensor Frame Reduction method to decrease the required channel bandwidth for applications such as autonomous driving.

Here, we propose a method that incorporates cross frame similarity measurement method to reduce the redundant frames and decrease the data rate of each …

Study Of Obstacle Effect On The Gpsr Protocol And A Novel Intelligent Greedy Routing Protocol For Vanets, Ravikumar Chilmula

Dissertations, Master's Theses and Master's Reports

In recent years, connected vehicle technologies have been developed by automotive companies, academia, and researchers as part of Intelligent Transportation Systems (ITS). This group of stakeholders continue to work on these technologies to make them as reliable and cost-effective as possible. This attention is because of the increasing connected vehicles safety-related, entertainment, and traffic management applications, which have the potential to decrease the number of road accidents, save fuel and time for millions of daily commuters worldwide.

Vehicular Ad-Hoc Network (VANET), which is a subgroup of Mobile Ad-Hoc Network (MANET), is being developed and implemented in vehicles as the critical …

Design Optimization And High Cycle Fatigue Analysis And Of A Differential Case, Praveen Bulusu Surya Naga

Dissertations, Master's Theses and Master's Reports

Lightweight Innovations for Tomorrow (LIFT) is a consortium with several industries, universities and research institutes. It is operated by the American Lightweight Materials Manufacturing Innovation Institute (ALMMII). One of their projects, melt 5a, is to develop high silicon ductile iron (DI) alloys with improved mechanical properties and thin walled DI castings. These alloys have high strength to weight ratio compared to that of standard ductile iron (7003). Using these alloys, components can be re-designed that are much lighter which results in improved fuel efficiency, and reduced manufacturing costs and emissions. I

In this project, a differential case is being re-designed …

Mpart: Miss Ratio Curve Guided Partitioning In Key-Value Stores, Daniel Byrne

Dissertations, Master's Theses and Master's Reports

Web applications employ key-value stores to cache the data that is most commonly accessed. The cache improves an web application’s performance by serving its requests from memory, avoiding fetching them from the backend database. Since the memory space is limited, maximizing the memory utilization is a key to delivering the best performance possible. This has lead to the use of multi-tenant systems, allowing applications to share cache space. In addition, application data access patterns change over time, so the system should be adaptive in its memory allocation. In this thesis, we address both multi-tenancy (where a single cache is used …

Reverse Insulator Dielectrophoresis: Utilizing Droplet Microenvironments For Discerning Molecular Expressions On Cell Surfaces, Jeana Collins

Dissertations, Master's Theses and Master's Reports

Lab-on-a-chip (LOC) technologies enable the development of portable analysis devices that use small sample and reagent volumes, allow for multiple unit operations, and couple with detectors to achieve high resolution and sensitivity, while having small footprints, low cost, short analysis times, and portability. Droplet microfluidics is a subset of LOCs with the unique benefit of enabling parallel analysis since each droplet can be utilized as an isolated microenvironment. This work explored adaptation of droplet microfluidics into a unique, previously unexplored application where the water/oil interface was harnessed to bend electric field lines within individual droplets for insulator dielectrophoretic (iDEP) characterizations. …

Modeling Canopy Effect In The Great Lakes Cladophora Model, Ankita Bakshi

Dissertations, Master's Theses and Master's Reports

Cladophora glomerata is a filamentous green alga native to the Great Lakes. However, its nuisance growth in phosphorus rich waters negatively affects the lakes’ aesthetic and water quality. The Great Lakes Cladophora Model (GLCM) v1, developed in 1982, was the first mechanistic model to simulate Cladophora growth basing phosphorus availability and environmental conditions followed by Cladophora Growth Model and GLCM v2. In this study, the light and temperature mediation factors for Cladophora net growth are revised as a necessary step prior to the development of a self-shading algorithm. The concept of a fixed-value, maximum achievable biomass (carrying capacity) employed in …

Exploring How Reflective Exercises Affect First-Year Engineering Epistemological And Intelligence Beliefs, Amber J. Kemppainen

Dissertations, Master's Theses and Master's Reports

This work explores the effects of the implementation of a KWL reflective learning exercise on first-year engineering students’ self-efficacy, intelligence beliefs (mindset), and epistemological beliefs. A sample of 428 first-year engineering students were divided into three groups: a) control, b) exposure to KWL, and c) used KWL. Significant differences were found in self-efficacy between the groups with more efficacious students being less likely to utilize the KWL activity. Seventy-seven percent of the students who used the KWL activities reported positive learning outcomes by using the KWL activity to focus their class preparation or to reflect on their learning. No significant …

Development Of Open Source Software And Hardware Tool-Chains For Novel Electronics, Shane Oberloier

Dissertations, Master's Theses and Master's Reports

3-D printing technologies have become widely adopted and have spurred innovation and efficiency across many markets. A large contributor to the success of 3-D printing are open source, low cost electronics. On-site circuit manufacturing, however, has not become as widely utilized as 3-D printing. This project attempts to address this problem by proposing and demonstrating an open source circuit board milling machine which is inexpensive, easily manufactured, and accurate. In three interdependent sub-projects, this thesis defines a standard method for designing open source hardware, the design of the bespoke circuit mill, and explores an application of the mill for novel …

Employing Dielectric-Based Media For Controlling Field Patterns And Wave Propagation In Advanced Electromagnetic Devices, Navid Pourramzan Gandji

Dissertations, Master's Theses and Master's Reports

Rapid progress in developing electromagnetic devices and in governing the wave propagation during last years caused renewed interest to dielectric materials. First, engineered dielectric structures with spatial dispersion of their parameters came to replace uniform substrates in antennas and other resonance devices. Then additional boom of dielectric applications was caused by the possibility to employ dielectrics as materials of artificial media. Later, attention of researchers was attracted to properties of the media composed of dielectric resonators (DRs). Currently DRs are used to create metamaterials – the media with unprecedented properties, which cannot be found in nature. Dielectric photonic crystals and …

Offline And Online Density Estimation For Large High-Dimensional Data, Aref Majdara

Dissertations, Master's Theses and Master's Reports

Density estimation has wide applications in machine learning and data analysis techniques including clustering, classification, multimodality analysis, bump hunting and anomaly detection. In high-dimensional space, sparsity of data in local neighborhood makes many of parametric and nonparametric density estimation methods mostly inefficient.

This work presents development of computationally efficient algorithms for high-dimensional density estimation, based on Bayesian sequential partitioning (BSP). Copula transform is used to separate the estimation of marginal and joint densities, with the purpose of reducing the computational complexity and estimation error. Using this separation, a parallel implementation of the density estimation algorithm on a 4-core CPU is …

Impact Of Inrush Currents And Geomagnetically Induced Currents On Transformer Behavior, Nishchal Sharma

Dissertations, Master's Theses and Master's Reports

Transformers are the tie-points of electrical power systems. Their protection from power system faults and other innate issues is of prime importance. A few of the issues that are studied in this report are magnetic inrush currents, geomagnetically induced currents in power transformers and Over-excitation.

This project develops a novel way of initializing and visualizing the flux linkage in the transformer core for studies on energization inrush currents. In addition, a quasi-DC source for GIC has been developed in order to study the GIC effects on power transformers and a sensitivity analysis has been carried out to understand effects of …

Spray And Combustion Studies Of High Reactivity Gasoline In Comparison To Diesel Under Advanced Compression Ignition Engine Conditions, Meng Tang

Dissertations, Master's Theses and Master's Reports

Gasoline compression ignition (GCI) technology has demonstrated great potentials in improving fuel economy and reducing engine-out NO_x and particulate matter emissions. Development and application of the GCI technology on multi-cylinder engines require both fundamental understandings of the gasoline spray combustion characteristics and accurate numerical tools. Due to the large differences in the thermo-physical and the chemical properties between gasoline and diesel range fuels, differences in the spray combustion characteristics between gasoline and diesel is expected. Reports on the gasoline spray combustion characteristics under conditions relevant to medium to heavy-duty engines are scarce and this dissertation aims to fill in …

Investigation Of Mechanical, Electrical, And Thermal Properties Of Particulate/Fiber/Polymer Composites, Julie Tomasi

Dissertations, Master's Theses and Master's Reports

Composites have many applications due to their high strength to weight ratio, chemical resistance, and the ability to tune properties like electrical resistivity (ER). In this work, polyetheretherketone (PEEK) and cycloaliphatic epoxy (CE) composites with different fillers were studied. PEEK composites contained up to 10 wt% Akzo Nobel Ketjenblack carbon black (CB), up to 15 wt% Asbury Carbons TC307 graphene nanoplatelets (GNP), up to 30 wt% Solvay carbon fiber (CF), and combinations of the three carbons. Formulations were developed for electrostatic dissipative and electrically conductive applications. The most conductive formulation was 7.5 wt% CB/30 wt% CF/PEEK, which had an electrical …

Thermomagnetic Convective Cooling Of Hall Effect Thruster, Elizabeth M. Vanheusden

Dissertations, Master's Theses and Master's Reports

This work proposes and shows that thermomagnetic convection could be used in zero gravity to cool components of a Hall-effect thruster. A ferrofluid cavity was develop in the thermal and geometric model of a Hall-effect thruster. Simulations show that with an Ionic Liquid Ferrofluid after two minutes of thruster operations thermomagnetic convection occurs and in zero gravity will produce a larger velocity then natural convection that occurs in earth gravity. However, experiments did not result in heat transfer enhancement due to the limitation of the ferrofluid. Replacement of the Ferrotec EFH1 dispersant with dodecylbenzene did not result in Ionic Liquid …

Intelligent And Secure Underwater Acoustic Communication Networks, Chaofeng Wang

Dissertations, Master's Theses and Master's Reports

Underwater acoustic (UWA) communication networks are promising techniques for medium- to long-range wireless information transfer in aquatic applications. The harsh and dynamic water environment poses grand challenges to the design of UWA networks. This dissertation leverages the advances in machine learning and signal processing to develop intelligent and secure UWA communication networks. Three research topics are studied: 1) reinforcement learning (RL)-based adaptive transmission in UWA channels; 2) reinforcement learning-based adaptive trajectory planning for autonomous underwater vehicles (AUVs) in under-ice environments; 3) signal alignment to secure underwater coordinated multipoint (CoMP) transmissions.

First, a RL-based algorithm is developed for adaptive transmission in …

Controlling Light With Metadevices, Xu Zhang

Dissertations, Master's Theses and Master's Reports

The development of metamaterials provides a new way to manipulate electromagnetic waves by sub-wavelength artificial structures, and hence brings new properties and functionalities that cannot be found with conventional materials. This leads to the possibility of previously unthought-of applications, including perfect lenses, invisibility cloaks, and perfect absorbers. However, several critical challenges need to be addressed before transiting from intriguing scientific findings to real-world usable devices.

This dissertation deals with two challenges regarding the practical use of metamaterials. Firstly, fabrication of truly three-dimensional (3D) and large-scale metamaterials is needed to increase the degrees of freedom of the functionality for device level …

Studying Mass And Mechanical Property Changes During The Degradation Of A Bioadhesive With Mass Tracking, Rheology And Magnetoelastic (Me) Sensors, Zhongtian Zhang

Dissertations, Master's Theses and Master's Reports

In this research, the degradable polymer 4-arm poly (ethylene glycol)-glutaric acid-dopamine (PEG-GA-DM₄) was synthesized. The degradation behavior of crosslinked PEG-GA-DM₄ bioadhesive was studied with mass tracking, oscillatory rheology, and magnetoelastic (ME) sensors. Changes in mechanical properties were correlated with both dry mass and wet mass changes during the degradation. The results indicate that the loss of mechanical property in the bioadhesive can take place without losing the dry mass. The mass loss profile cannot describe the degradation behavior completely. In addition to studying the degradation of PEG-GA-DM₄, this research also confirms the application of ME …

Application Of Remote Sensing And Machine Learning Modeling To Post-Wildfire Debris Flow Risks, Priscilla Addison

Dissertations, Master's Theses and Master's Reports

Historically, post-fire debris flows (DFs) have been mostly more deadly than the fires that preceded them. Fires can transform a location that had no history of DFs to one that is primed for it. Studies have found that the higher the severity of the fire, the higher the probability of DF occurrence. Due to high fatalities associated with these events, several statistical models have been developed for use as emergency decision support tools. These previous models used linear modeling approaches that produced subpar results. Our study therefore investigated the application of nonlinear machine learning modeling as an alternative. Existing models …

Optimal Control Of Wave Energy Converters, Shangyan Zou

Dissertations, Master's Theses and Master's Reports

In this dissertation, we address the optimal control of the Wave Energy Converters. The Wave Energy Converters introduced in this study can be categorized as the single body heaving device, the single body pitching device, the single body three degrees of freedoms device, and the Wave Energy Converters array. Different types of Wave Energy Converters are modeled mathematically, and different optimal controls are developed for them. The objective of the optimal controllers is to maximize the energy extraction with and without the motion and control constraints. The development of the unconstrained control is first introduced which includes the implementation of …

Predicting The Organic Compound Degradation In Aqueous-Phase Ultraviolet (Uv) And Uv-Based Advanced Oxidation Processes, Erica Coscarelli

Dissertations, Master's Theses and Master's Reports

Clean safe drinking water is vital for society. With increasing water scarcity and the increased numbers of chemicals identified in waterways, it is important for us to fully understand how to destroy contaminants of concern and prevent potentially hazardous byproducts that may be produced from the degradation processes. Little is known about how nitrogen containing organics behave and degrade in current water treatment systems and therefore their role in water reuse. N-nitrosodimethylamine (NDMA), is carcinogenic and is being formed during conventional chlorination of drinking water. Ultraviolet (UV) photooxidation has been shown to degrade NDMA, but the degradation pathways and their …

Implementing Write Compression In Flash Memory Using Zeckendorf Two-Round Rewriting Codes, Vincent T. Druschke

Dissertations, Master's Theses and Master's Reports

Flash memory has become increasingly popular as the underlying storage technology for high-performance nonvolatile storage devices. However, while flash offers several benefits over alternative storage media, a number of limitations still exist within the current technology. One such limitation is that programming (altering a bit from its default value) and erasing (returning a bit to its default value) are asymmetric operations in flash memory devices: a flash memory can be programmed arbitrarily, but can only be erased in relatively large batches of storage bits called blocks, with block sizes ranging from 512K up to several megabytes. This creates a situation …

Nondestructive Evaluation Of Salvage White Spruce, Tyler Hovde

Dissertations, Master's Theses and Master's Reports

Knowledge of wood quality in dead standing trees is an important topic with recent increases in defoliation across North America. Obtaining wood quality information for defoliated trees would help stakeholders in the timber products industry sort and sell salvaged material for the highest possible value. This research investigates the ability to measure wood quality of white spruce (Picea glauca) after spruce budworm (Choristoneura fumiferana) attack using acoustic nondestructive evaluation. We compared stress wave velocities measured on standing trees to trees’ visual appearance. After harvest and processing of selected trees into bolts, standing-tree stress wave velocities were compared to bolt acoustic …

Transient Simulations Of Freshwater Lens Depletion In Response To A Range Of Sea Level Rise Rates And Climate Gradients, Qiuyuan Nan

Dissertations, Master's Theses and Master's Reports

The freshwater lens in the island can become the only freshwater resources in some regions. Numerical simulations are used to determine freshwater lens volume and average concentration is in response to the range of sea-level rise rates and climate gradients. The sea-level rise rates (0.56 mm/yr, 6.22 mm/yr, and 11.78 mm/yr) are selected for projected and the climate gradient is computed from the islands in the Bahamian archipelago (Inagua, San Salvador, and Grand Bahamas) in the north, central and south. Based on the simulation results, all cases presented the upward trend of the average salinity but have the oscillation in …

Multi-Robot Mission Planning With Energy Replenishment, Bingxi Li

Dissertations, Master's Theses and Master's Reports

Success of numerous long-term robotic explorations in air, on the ground, and under water is dependent on the ability of the robots to operate for an extended period of time. The continuous operation of robots hinges on smart energy consumption and replenishment of the robots. This dissertation addresses the multi-robot system continuous operation problem by developing two mission planning architectures regarding two types of energy replenishment, which can be adapted to different mission scenarios based on mission requirements and available resources.

The first type of energy replenishment utilizes static charging stations to provide a recharging opportunity to primary working robots, …

Optimizing Chlorine Disinfection By Chlorine Injection Location And Pipe Diameter Selection In A Water Distribution System, Margaret Neff

Dissertations, Master's Theses and Master's Reports

Due to a variety of factors chlorination is common water disinfectant for community-scale distribution systems. The town of Suyo, Peru was already equipped with a gravity fed water system and drip chlorinator which achieved 4-log inactivation of viruses throughout the town, however, it was not providing 3-log inactivation of giardia cysts at all points of the system.

This project used an EPANET model to determine and compare the potential benefits of changes which could be made to the pre-existing water system in Suyo.

The model was used to compare current operating conditions of the Suyo system, 1.5 mg/L chlorine addition …