Engineering Commons^™

Zirconium Diboride, Hexagonal Boron Nitride, And Amorphous Alumina Thin Films For High Temperature Applications, David Murdock Stewart

Electronic Theses and Dissertations

The use of microelectronic sensors and actuators in harsh, high temperature environments, such as power plants, turbine engines, and industrial manufacturing, could greatly improve the safety, reliability, and energy efficiency of these processes. The primary challenge in implementing this technology is the breakdown and degradation of thin films used in fabricating these devices when exposed to high temperatures >800 °C and oxidizing atmospheres. Zirconium diboride, hexagonal boron nitride, and amorphous alumina are candidate materials for use as thin film sensor components due to their high melting temperatures and stable phases. Zirconium diboride thin films have metallic-like electrical conductivity and remain …

Experimental Methods And Practices For The Study Of Toroidal Inflated, Braided Fabric Members, Daniel J. Whitney

Electronic Theses and Dissertations

Inflatable structures have become a very important area of interest for many differing applications where lightweight packable structures are required. NASA is developing Hypersonic Inflatable Aerodynamic Decelerator (HIAD) technology that takes advantage of stacked, inflated fabric tori to form a decelerating spacecraft nose cone. The tori consist of a bladder, braided fabric shell, and reinforcing in the form of integral cords or externally bonded straps. The focus of this thesis is on the development of methods for the structural testing of inflated fabric tori and developing an enhanced understanding of their behavior. This is essential for providing insight into the …

Microstructural Analysis Of Thermoelastic Response, Nonlinear Creep, And Pervasive Cracking In Heterogeneous Materials, Alden C. Cook

Electronic Theses and Dissertations

This dissertation is concerned with the development of robust numerical solution procedures for the generalized micromechanical analysis of linear and nonlinear constitutive behavior in heterogeneous materials. Although the methods developed are applicable in many engineering, geological, and materials science fields, three main areas are explored in this work. First, a numerical methodology is presented for the thermomechanical analysis of heterogeneous materials with a special focus on real polycrystalline microstructures obtained using electron backscatter diffraction techniques. Asymptotic expansion homogenization and finite element analysis are employed for micromechanical analysis of polycrystalline materials. Effective thermoelastic properties of polycrystalline materials are determined and compared …

Characterization And Delineation Of Karst Geohazards Along Rm652 Using Electrical Resistivity Tomography, Culberson County, Texas, Adam F. Majzoub

Electronic Theses and Dissertations

The Delaware Basin of West Texas and southeastern New Mexico is the major western subdivision of the Permian Basin and a northern extension of the Chihuahuan Desert. The major evaporite unit within the Delaware Basin is the Castile Formation, which consists of gypsum/anhydrite and is highly susceptible to dissolution and karsting. Manifestations of karst within the Castile outcrop are abundant and include sinkholes, subsidence features and caves, both epigene and hypogene in origin.

Land reconnaissance surveys conducted during the summer of 2015 documented abundant karst landforms in close proximity to a major thoroughfare, RM 652, in Culberson County, Texas. 2D …

Practical Knowledge In Electrical Engineering : Applying Lessons From Industry To The Classroom., Tayce Lassiter

Electronic Theses and Dissertations

Objective: To identify and develop solutions for known gaps in existing electrical engineering curricula, by creating instruction modules applicable in a variety of settings. These instructional packages include: conductor sizing, conduit routing, how to read and create a P&ID, arc flash calculations, and area classification. With regards to conductor sizing, the importance of specifying the correct size of conductor, the standard sizes of conductors, the types of conductor insulation, and finally detail the calculations of conductor sizing and voltage drop will be discussed. The conduit routing module will introduce the student to basic guidelines of conduit routing as well as …

Computational Methods For The Analysis Of Functional 4d-Ct Chest Images., Ahmed Soliman Naeem Soliman

Electronic Theses and Dissertations

Medical imaging is an important emerging technology that has been intensively used in the last few decades for disease diagnosis and monitoring as well as for the assessment of treatment effectiveness. Medical images provide a very large amount of valuable information that is too huge to be exploited by radiologists and physicians. Therefore, the design of computer-aided diagnostic (CAD) system, which can be used as an assistive tool for the medical community, is of a great importance. This dissertation deals with the development of a complete CAD system for lung cancer patients, which remains the leading cause of cancer-related death …

Single Carrier Frequency Domain Equalization And Energy Efficiency Optimization For Mimo Cognitive Radio., Xiaohui Zhang

Electronic Theses and Dissertations

This dissertation studies two separate topics in wireless communication systems. One topic focuses on the Single Carrier Frequency Domain Equalization (SC-FDE), which is a promising technique to mitigate the multipath effect in the broadband wireless communication. Another topic targets on the energy efficiency optimization in a multiple input multiple output (MIMO) cognitive radio network. For SC-FDE, the conventional linear receivers suffer from the noise amplification in deep fading channel. To overcome this, a fractional spaced frequency domain (FSFD) receiver based on frequency domain oversampling (FDO) is proposed for SC-FDE to improve the performance of the linear receiver under deep fading …

Conductive Inks And Films Via Intense Pulsed Light., Gabriel L. Draper

Electronic Theses and Dissertations

This research focuses on the investigation of Earth abundant copper and carbon based nanomaterials that are subjected to Intense Pulsed Light Processing to create conductive films, as future flexible electronics and renewable energy solutions would benefit from the quick and scalable production of conductive films. Use of nanomaterials in their oxide/hydroxide forms leads to higher stability in aqueous inks for efficient large area solution deposition. IPL Processing utilized 2044 μs pulses ranging from 589 J - 2070 J over an area of 1.9 cm x 30.5 cm, with energy densities of 10.1, 12.8, 15.8, 19.2, 22.9, 26.8, 31.1 and 35.7 …

Scalable Production And Applications Of Metal Oxide Nanowires., Tu Quang Nguyen

Electronic Theses and Dissertations

Metal oxide nanowires are materials of interest in number of applications such as lithium ion batteries, solar cells, catalyst support, and gas sensing due to their unique charge transport properties and short diffusion length scales. To incorporate nanowires for any applications, one would need hundreds of grams to kilograms of these nanowires. However, state-of-the-art methods for producing metal oxide nanowires are limited to producing only milligrams to a gram in a batch. Hence, there is a need to develop scalable and cost effective processes and reactors to address this challenge. Direct gas phase oxidation of zinc metal powders using a …

Psychophysiological Analysis Of A Pedagogical Agent And Robotic Peer For Individuals With Autism Spectrum Disorders., Mohammad Nasser Saadatzi

Electronic Theses and Dissertations

Autism spectrum disorder (ASD) is a neurodevelopmental disorder characterized by ongoing problems in social interaction and communication, and engagement in repetitive behaviors. According to Centers for Disease Control and Prevention, an estimated 1 in 68 children in the United States has ASD. Mounting evidence shows that many of these individuals display an interest in social interaction with computers and robots and, in general, feel comfortable spending time in such environments. It is known that the subtlety and unpredictability of people’s social behavior are intimidating and confusing for many individuals with ASD. Computerized learning environments and robots, however, prepare a predictable, …

Strategies And Techniques For Fabricating Mems Bistable Thermal Actuators., Dilan Ratnayake

Electronic Theses and Dissertations

Bistable elements are beginning to appear in the field of MEMS as they allow engineers to design sensors and actuators which require no electrical power and possess mechanical memory. This research focuses on the development of novel strategies and techniques for fabricating MEMS bistable structures to serve as no electrical power thermal actuators. Two parallel strategies were explored for the design and fabrication of the critical bistable element. Both strategies involved an extensive material study on candidate thin film materials to determine their temperature coefficient of expansion and as-deposited internal stress properties. Materials investigated included titanium tungsten, Invar, silicon nitride …

An Integrated Economic Equilibrium Model For Electricity Markets., Swapna Pothabathula

Electronic Theses and Dissertations

The increasing energy challenges worldwide are forcing researchers to explore ways for energy systems that work more efficiently on their own and with each other. This thesis develops an integrated electricity market equilibrium model (EMEM) as a mixed complementarity problem (MCP). In particular, we first develop an equilibrium model to study an electricity market consisting of coal producers, electricity generation firms, natural gas producers, natural gas marketers, natural gas pipeline owners, natural gas consumers and electricity consumers. The equilibrium model not only captures a decentralized optimization for each player but considers the interaction amongst players. Second, we formulate the equilibrium …

Experimental Observation Of The Relationship Between The Pressure Drop And Flow Rate Of Radial Flow Through Porous Media., Matthew William Okruch

Electronic Theses and Dissertations

This research experimentally observed the relationship between pressure drop and flow rate for high velocity, radial flow through porous media. The criterion for what represents high velocity is a function of the Reynold’s number of the flow. Pressure drop – flow rate curves were developed by flowing air and water through the porous carbon block samples. Each sample’s permeability was calculated from on the air test results. Each sample’s porosity was determined through digital microscope image analysis. Darcy’s Law, the Forchheimer equation, and the Ergun equation were converted to the radial flow domain and compared to the experimental data. The …

Optimization Models And Algorithms For Demand Response In Smart Grid., Guangyang Xu

Electronic Theses and Dissertations

For demand response in smart grid, a utility company wants to minimize total electricity cost and end users want to maximize their own utility. The latter is considered to consist of two parts in this research: electricity cost and convenience/comfort. We first develop a system optimal (SO) model and a user equilibrium (UE) model for the utility company and end users, respectively and compare the difference of the two. We consider users' possible preference on convenience over cost-saving under the real-time pricing in smart grid, and each user is assumed to have a preferred time window for using a particular …

Order Picking Strategies For Healthcare Warehouses., Ehsan Khodabandeh

Electronic Theses and Dissertations

Order picking is the process of collecting goods and items in specified quantities from storage locations, in response to customer orders. Since many labor resources are involved in this process, finding ways to make it more efficient have been a primary goal for researchers and practitioners. Determining a better allocation of products to the storage areas, finding the best route and sequence to pick multiple products, and choosing the best picking policies to minimize congestion in the aisles are just a few of many objectives regarding order picking process. Due to regulatory compliances and the chance of product spoilage, additional …

A Reduced Labeled Samples (Rls) Framework For Classification Of Imbalanced Concept-Drifting Streaming Data., Elaheh Arabmakki

Electronic Theses and Dissertations

Stream processing frameworks are designed to process the streaming data that arrives in time. An example of such data is stream of emails that a user receives every day. Most of the real world data streams are also imbalanced as is in the stream of emails, which contains few spam emails compared to a lot of legitimate emails. The classification of the imbalanced data stream is challenging due to the several reasons: First of all, data streams are huge and they can not be stored in the memory for one time processing. Second, if the data is imbalanced, the accuracy …

A Cad System For Early Diagnosis Of Autism Using Different Imaging Modalities., Marwa Maher Tawfik Ismail

Electronic Theses and Dissertations

The term “autism spectrum disorder” (ASD) refers to a collection of neuro-developmental disorders that affect linguistic, behavioral, and social skills. Autism has many symptoms, most prominently, social impairment and repetitive behaviors. It is crucial to diagnose autism at an early stage for better assessment and investigation of this complex syndrome. There have been a lot of efforts to diagnose ASD using different techniques, such as imaging modalities, genetic techniques, and behavior reports. Imaging modalities have been extensively exploited for ASD diagnosis, and one of the most successful ones is Magnetic resonance imaging(MRI),where it has shown promise for the early diagnosis …

Simulation Modeling For Energy Consumption Of Residential Consumers In Response To Demand Side Management., Prajwal Khadgi

Electronic Theses and Dissertations

Energy efficiency in the electricity distribution system continues to gain importance as demand for electricity keeps rising and resources keep diminishing. Achieving higher energy efficiency by implementing control strategies and demand response (DR) programs has always been a topic of interest in the electric utility industry. The advent of smart grids with enhanced data communication capabilities propels DR to be an essential part of the next generation power distribution system. Fundamentally, DR has the ability to charge a customer the true price of electricity at the time of use, and the general perception is that consumers would shift their load …

Mechanism Of Interaction Of Peptide Modified Nanoparticles With Porphyromonas Gingivalis., Ankita Jain

Electronic Theses and Dissertations

Studies suggest that P. gingivalis functions as a keystone pathogen and interacts with primary colonizers in the supragingival biofilm such as S. gordonii. This interaction contributes to the initial colonization of the oral cavity by P. gingivalis and thus represents a potential target for therapeutic intervention. We have identified a peptide (BAR) derived from the streptococcal SspB protein that functions to inhibit P. gingivalis adherence to S. gordonii. In addition, we showed that nanoparticles (NPs) functionalized with BAR inhibit this interaction more potently than free soluble peptide, possibly by promoting interaction with P. gingivalis at higher valency than …

Geotechnical Properties Of The Travis Peak (Hosston) Formation In East Texas: A Compressive And Tensile Strength Analysis Using Regression Analysis., Pawan Kakarla

Electronic Theses and Dissertations

The estimation of rock mass strength is a key parameter in geotechnical engineering which is used in the design of geotechnical structures like tunnels, dams and slopes. Geotechnical engineering is the branch of civil engineering which works on the principles of soil and rock mechanics to evaluate subsurface conditions, stability of slopes, foundations of structures and construction of earthworks. The main focus of this study was to calculate the strength of Lower Cretaceous Travis Peak Formation rocks of East Texas and to check the accuracy by comparing it with Regression analysis. The parameters which were used were the Uniaxial Compression …

Dynamic Warehouse Optimization Using Predictive Analytics., Parvaneh Jahani

Electronic Theses and Dissertations

The forward area is a small area of a warehouse with a low picking cost. Two approaches that are investigated for selecting the SKUs of this area and the allocated space are the static and the dynamic approaches. In the case that decisions about the forward area are made periodically (e.g. yearly) and the products' demand patterns are completely ignored, the FRP is static. We developed two heuristics that solve the large discrete assignment, allocation, and sizing problem simultaneously. Replenishing the same product in the same place of the forward area brings about a ``Locked" layout of the fast picking …

Study Of Spatiotemporal Rainfall Structure And Optimized Local Radar Rainfall Application To Urban Watershed, Louisville, Kentucky, 2010-2014., Jin-Young Hyun

Electronic Theses and Dissertations

In urban areas, a prevalence of combined sewer systems (CSS) exist that carry both storm water runoff and sanitary sewer flows in a single pipe, these system are considered combined sewers. In the absence of rainfall-runoff most of these systems function adequately, however CSS capacity is typically inadequate to carry peak stormwater runoff volume. In order to minimize sewage flooding into streets and backups into homes and businesses, most CSSs (as well as separate sanitary sewer systems) are designed to overflow into surface waters such as streams and rivers, lakes and seas. This occurrence is considered a combined sewer overflow …

A Multi-Channel 3d-Printed Bioreactor For Evaluation Of Growth And Production In The Microalga Dunaliella Sp, Cristian A. Cox

Electronic Theses and Dissertations

We explored the capabilities of additive manufacturing using a photo-cured jetted material 3D printer to manufacture a milli-microfluidic device with direct application in microalgae Dunaliella sp growth and intracellular compounds biosynthesis tests. A continuous microbioreactor for microalgae culture was CAD designed and successfully built in 1 hour and 49 minutes using black photopolymer cured by UV and a support material. The microreactor was made up of 2 parts including the bioreactor itself and a microchannel network for culture media fluids and microalgae. Both parts were assembled to form a single unit. Additional optical and auxiliar components were added. An external …

Reflectivity Of Light Emitting Diodes (Led) And Incandescent Lights On Concrete And Asphalt Pavements., Jeremy Elliott Rice

Electronic Theses and Dissertations

The purpose of this study is to investigate the reflectivity of light on concrete and asphalt pavement systems. In 1983, the Illuminating Engineering Society (IES) published the first recommended practice (RP-8) for the design of roadway and parking lot lighting. This design method implemented empirically tested factors which were defined as the “reduced luminance coefficients” or the R-Tables. The R-Tables are essential for proper design of light pole installation dimensions, required power, and the distribution of light. The originally tested pavements are not necessarily representative of modern pavement materials used today. Moreover, recent Light Emitting Diodes (LED) are a relatively …

Identification Of Critical Locations And Reduced Model State Estimation For Power System Analysis, Amamihe Onwuachumba

Electronic Theses and Dissertations

In order to reduce the carbon footprint and the cost of electric energy, the owners of electric power utilities today are faced with the task of reducing the use of expensive and carbon intensive fossil fuels and significantly increasing the amount of energy from renewable sources in their grids while meeting an increase in electricity demand. To deal with increase in demand, electric utilities operate very close to their maximum capacities and this sometimes results in violating security limits. Therefore, the integration of intermittent renewable energy into the utility grids poses serious concerns that must be addressed to ensure grid …

Analysis And Recommendations To Improve Traffic Safety & Flow For Pedestrians Bicyclists And Motorists Along Franklin Street, Matthew Pelletier

Electronic Theses and Dissertations

Franklin Street is a minor arterial servicing Portland, Maine that connects Commercial Street and Route 1 to I-295 and has been a target for redevelopment for some time. Franklin is the epitome of traffic congestion, and has unsafe conditions for pedestrians, bicyclists and motorists alike. Portland is the biggest city in Maine and is an important hub for employment, housing and tourism throughout the year. As the city grows, there is a greater demand to build more sustainable, multi-use streets to service all modes of transportation that supports business development, open space and growth. This new vision is being applied …

Development Of Eco-Friendly Composite Foam Boards For Thermal Insulation And Packaging Purposes Using Cellulose Nanofibrils (Cnf), Nadir Yildirim

Electronic Theses and Dissertations

Reducing energy consumption is a high priority in the United States and throughout the world. Energy used to heat and cool occupied constructed facilities is of particular concern, and one of the most effective strategies is insulating the building envelope. Historically, builders used whatever material was available to fill the void between interior and exterior walls, including wool fibers, paper, and even corn cobs. Today, homes are built using foam insulation that harden when applied, blown-in loose insulation, fiberglass mats or rigid foam boards usually composed of polystyrene. Rigid foam boards are used in a variety of applications despite the …

Simultaneous Behavior Onset Detection And Task Classification For Patients With Parkinson Disease Using Subthalamic Nucleus Local Field Potentials, Nazanin Zaker Habibabadi

Electronic Theses and Dissertations

This thesis aims to develop of methods for behavior onset detection of patients with Parkinson's disease (PD), as well as to investigate the models for classification of different behavioral tasks performed by PD patient. The detection is based on recorded Local Field Potentials (LFP) of the Subthalamic nucleus (STN), captured through Deep Brain Stimulation (DBS) process.

One main part of this work is dedicated to the research of various properties and features of the STN LFP signals of several patients' behavior conditions. Features based on temporal and time-frequency analysis of the signals are developed and implemented. Evaluation and comparison of …

Osem : Occupant-Specific Energy Monitoring., Anand S. Kulkarni

Electronic Theses and Dissertations

Electricity has become prevalent in modern day lives. Almost all the comforts people enjoy today, like home heating and cooling, indoor and outdoor lighting, computers, home and office appliances, depend on electricity. Moreover, the demand for electricity is increasing across the globe. The increasing demand for electricity and the increased awareness about carbon footprints have raised interest in the implementation of energy efficiency measures. A feasible remedy to conserve energy is to provide energy consumption feedback. This approach has suggested the possibility of considerable reduction in the energy consumption, which is in the range of 3.8% to 12%. Currently, research …

Gamma-Radiation Exposure Alters The Cardiovascular Extracellular Matrix., Nicholas Allen

Electronic Theses and Dissertations

Ionizing radiation has been associated with various cardiovascular complications; however, the associated molecular changes from radiation exposure still remain largely uncharacterized. Alterations to the cardiovascular tissue microenvironment, i.e. the extracellular matrix (ECM), directly affect the function of integrated vascular cells, including cell adhesion, potential to form vessels, and endothelial permeability, which can promote cardiovascular pathologies. The ECM is constantly remodeled in response to stimuli, such as TGF-β1, which leads to excessive ECM accumulation. We hypothesize that radiation exposure will alter the cardiovascular ECM. Human Cardiac Fibroblasts (HCFs) were utilized to produce ECM as an in vitro model to study changes …