Engineering Commons^™

Wireless Monitoring Of Driver's Pulse Rate And Temperature Using Hand Gloves Approach, Rohith Reddy Narala

Graduate Theses and Dissertations

There is growing concern about dangers correlated with driving, for people with known cardiovascular diseases. However, the association between having a chronic cardiovascular disease and being involved in a motor vehicle crash remains controversial. This study aims to monitor people with known medical emergencies or other medical conditions while driving [1]. It also helps the co-passengers to be cautious while the person is driving with an abnormal health condition. Designed it to be convenient and also can be easily adaptable by the end user.

The proposed project focuses on a wearable sensor glove that equipped with a pulse rate sensor, …

High-Frequency Transformer Design For Solid-State Transformers In Electric Power Distribution Systems, Roderick Javier Garcia Montoya

Graduate Theses and Dissertations

The objective of this thesis is to present a high- or medium-frequency transformer design methodology for Solid-State Transformer (SST) applications. SSTs have been proposed as a replacement of the traditional 50/60 Hz transformer in applications demanding high-power density. Moreover, due to the high penetration of distributed generation, DC grids, energy storage systems, and sensitive loads, SSTs have been considered as an enabling technology for envisioned future energy systems. These applications demand additional functionalities that may not be achieved with traditional transformers. For example, active power flow control, harmonic suppression, voltage regulation, voltage sag compensation, and reduced size and volume.

In …

Field Amplified Sample Stacking On Amyloid Beta (1-42) Oligomers Using Capillary Electrophoresis, Sadia Ali Paracha

Graduate Theses and Dissertations

According to recent literature, it is believed that the oligomeric form of amyloid beta (Aβ) is the leading cause of Alzheimer’s disease (1; 8; 10; 12-18). Additionally, recent studies have eluded to the impact of Alzheimer’s disease (AD) both economically and Socially in today’s society where an increase of about 71% of AD related deaths were recorded between 2000 and 2013 (7). Since the oligomeric forms of Aβ vary in size, shape and some believe conformation, it is vital to utilize a separation technique, such as capilllary electrophoresis (CE) to further understand Aβ aggregation. By understanding Aβ aggregation, treatment of …

Production Of Ethanol From Cereal Food Fines Using Dilute-Acid Hydrolysis, Andrew Edward Arnett

Graduate Theses and Dissertations

Cereal food fines are a leftover by-product from breakfast cereal processing that is typically sold as animal feed or used as a pet food ingredient; however this product could be of greater value as a feedstock for the production of fuel ethanol via fermentation. In order for this material to be fermented it has to be broken down in to simple sugars using hydrolysis. One method of hydrolysis is called dilute-acid hydrolysis, whereby low concentrations of acid are added to the feedstock to facilitate the breaking of chemical bonds. This study investigates the effect of different concentrations of acid to …

High Temperature Silicon Carbide Mixed-Signal Circuits For Integrated Control And Data Acquisition, Ashfaqur Rahman

Graduate Theses and Dissertations

Wide bandgap semiconductor materials such as gallium nitride (GaN) and silicon carbide have grown in popularity as a substrate for power devices for high temperature and high voltage applications over the last two decades. Recent research has been focused on the design of integrated circuits for protection and control in these wide bandgap materials. The ICs developed in SiC and GaN can not only complement the power devices in high voltage and high frequency applications, but can also be used for standalone high temperature control and data acquisition circuitry.

This dissertation work aims to explore the possibilities in high temperature …

Traction-Separation Relationships For Hydrogen-Induced Grain Boundary Embrittlement In Nickel Via Molecular Dynamics Simulations, Wesley Allen Barrows

Graduate Theses and Dissertations

The deleterious effects of atomic and molecular hydrogen on the mechanical properties of metals have long been observed. Although several theories exist describing the mechanisms by which hydrogen negatively influences the failure of materials, a consensus has yet to be reached regarding the exact mechanism or combination of mechanisms. Two mechanisms have gained support in explaining hydrogen’s degradative role in non-hydride forming metals: hydrogen-enhanced localized plasticity and hydrogen-enhanced decohesion. Yet, the interplay between these mechanisms and microstructure in metallic materials has not been explained. Accordingly, for this thesis, the three main objectives are: (i) to develop a numerical methodology to …

Alkali Silica Reaction Mitigation Using High Volume Class C Fly Ash, William Joseph Phillips

Graduate Theses and Dissertations

Alkali-Silica Reaction (ASR) is a neutralization reaction that occurs between an acid (silicic acid) and a basic pH pore solution (Calcium Oxide, Potassium Oxide, and Sodium Oxide). ASR causes deleterious expansion within concrete, which can cause durability issues decreasing the life span of concrete. ASR in concrete has been found in increasing quantities since its discovery in 1940 by Stanton. Several cases of ASR have occurred in Arkansas near Fayetteville, Pine Bluff, and Little Rock. The purpose of this research was to develop preventative measures using Class C fly ash in concrete, which contains the moderately reactive aggregates found in …

Swelling-Etching Characterization Of Copper (I) Oxide - Pdms For The Development Of Micro/Nano - Particles Composite Mems Corrosion Sensor, Abdoul Kader Maiga

Graduate Theses and Dissertations

The primary objective for this thesis is to contribute to the understanding of the oxide removal process for a corrosion sensing device. The goal for designing such a device is for monitoring corrosion on metallic structures. The sensing material (6.35mm x 1mm discs) of the device is composed of copper (I) oxide particles mixed in some polydimethylsiloxane (PDMS). The PDMS, “housing,” is meant for controlling the oxidation rate through the sensing material. A solvent was used to facilitate the etchant diffusion through the PDMS matrix. Toluene and acetic acid were the ideal solvent and etchant, respectively, for carrying out the …

Modeling Radiation Heat Transfer For Building’S Cooling And Heating Loads: Considering The Role Of Clear, Cloudy, And Dusty Conditions In Hot And Dry Climates, Salem Ahmed Algarni

Graduate Theses and Dissertations

The influence of transient factors such as sky long wave radiation exchange and atmospheric aerosols (i.e., smog, and dust – made up of sand, clay, and silt) are not carefully considered in current building design and simulation models. Therefore, the research objective was to better understand and account for such variables, resulting in improved radiative predictive capabilities, especially important for hot and dry climates under different sky conditions including clean, cloudy, and dusty. Overall, results of this dissertation provided a better prediction method for sky long wave radiation exchange with a building’s roof and the impact of dust accumulation on …

Fabrication Of Sub-10 Nm Metallic Structures Via Nanomasking Technique For Plasmonic Enhancement Applications, Stephen Joseph Bauman

Graduate Theses and Dissertations

One area of nanoscience that has become popular in recent years is the study of optics at the nanoscale. Due to enhanced fabrication techniques, new geometries and improved dimensional resolutions have been allowing the creation of nanostructures for use in this area. Nanoscale geometries cause unique optical effects such as enhancement of the signal’s electric field strength at the surface of a substrate. Specifically, structures separated by nanogaps (10 nm and smaller) have been shown to exhibit strong field enhancement within the gaps. This has opened up the potential for surface enhanced spectroscopies, enhanced absorption for photovoltaics, and improved sensing …

A Cradle To Farm Gate Life Cycle Analysis Of Land Use In U.S. Pork Production, William Benjamin Putman

Graduate Theses and Dissertations

The goal of this study was to conduct a detailed Life Cycle Assessment (LCA) of the U.S. live swine production supply chain to quantify land use requirements and to assess the impact associated with various ration compositions. The functional unit was defined as one kilogram (2.2 pounds) of live swine at the farm gate, ready for transport to the abattoir. This assessment focused on the three highest producing USDA regions, which encompassed the Midwest (Regions 5 and 7) and the Southeast (Region 4), representing 86% of U.S. market hog production.

First, a literature review was conducted to summarize the most …

Numerical Simulation Of Terahertz Wave Interaction With Breast Cancer Tumor Tissue Sections, Abayomi Omotola Omolewu

Graduate Theses and Dissertations

This thesis presents numerical simulation of terahertz (THz) wave interaction with breast cancer tumor tissue sections. The obtained results are expressed in THz images of heterogeneous material that mimics the excised breast cancer tissue sections. The finite-element software package ANSYS High Frequency Structural Simulator (HFSS) was used in this work. HFSS is a full wave frequency domain three-dimensional (3D) electromagnetic simulation package. In this work, four breast cancer tissue models based on pathology images were simulated and images of the models were obtained at 1 THz. An incident Gaussian beam was raster scanned over tissue model configurations and the reflected …

Surface Modification Of Noble Metal Nanostructures Toward Biomedical Applications, Samir V. Jenkins

Graduate Theses and Dissertations

Noble metal nanostructures have seen a steady increase in biomedical application over the last several decades; new diagnostic and therapeutic modalities are under intense investigation. Many of these applications are possible because of post-synthetic modifications to the particle surface. These modifications take a variety of forms and can significantly affect the pharmacokinetics of these particles. In this work, various surface modifications were investigated. Particle agglomeration, which occurs when particle surfaces remain in contact, can significantly affect the toxicity and efficacy of a nanomedicine. Darkfield microscopy and single-particle ICP-MS were developed as complementary methods to detect agglomeration in blood, with the …

Preventive Maintenance Decision Modeling In Health And Service Systems, Mahboubeh Madadi

Graduate Theses and Dissertations

This dissertation focuses on the preventive maintenance decision modeling in healthcare and service systems. In the first part of this dissertation, some issues in preventive health decisions for breast cancer are addressed, and in the second part, the required characteristics for preventive maintenance of an unreliable queuing system are derived.

Adherence to cancer screening is the first issue that is addressed in this dissertation. Women’s adherence or compliance with mammography screening remained low in the recent years. In this dissertation, we first develop a design-based logistic regression model to quantify the probability of adherence to screening schedules based on women’s …

The Effects Of Strain And Vacancies On The Electric And Vibrational Properties Of Ferroelectric Batio3 From First-Principles, Aldo Serge Michael Raeliarijaona

Graduate Theses and Dissertations

The studies of ferroelectricity (FE) are of technological significance because of the multitude of applicable properties that ferroelectric materials exhibit. The mastery, and control of these properties necessitate the knowledge of the fundamental physics governing these insulating materials.

In this dissertation I present the results of first-principles investigations of the behavior of the fundamental ferroelectric properties under strain, and in the presence of vacancies. In the first part I introduce the important FE properties, their common behavior, and their numerous valuable applications. Following this background on FEs, a review of theoretical methods is presented with topics such as: Density Functional …

Adaptive Controller Using Runtime Partial Hardware Reconfiguration For Unmanned Aerial Vehicles (Uavs), Nikhil Thomas

Graduate Theses and Dissertations

The goal of this thesis is to explore the feasibility of a multirotor controller system which can dynamically change the arm configuration of a multirotor. Currently most of the multirotor systems have to be powered down, rewired, and programmed with new firmware, to configure how many arms/motors they use to fly. The focus of our effort is to develop a Field Programmable Gate Array (FPGA) based hardware/software controller which uses dynamic partial hardware reconfiguration to switch the arm/motor configuration of a multirotor during operation. We believe that this will make a multirotor more fault tolerant and adaptive. This thesis explains …

Development And Characterization Of Intermediate-Band Quantum Wire Solar Cells, Colin Stuart Furrow

Graduate Theses and Dissertations

The effects of a quantum wire intermediate band, grown by molecular beam epitaxy, on the optical and electrical properties of solar cells are reported. To investigate the behavior of the intermediate band, the quantum wires were remotely doped at three different doping concentrations, the number of quantum wire layers was varied from three to twenty, and the solar cell structure was optimized. For all the structures, current-voltage and external quantum efficiency measurements were performed to examine the effect of absorption and power conversion of the intermediate band solar cell (IBSC). Time-resolved photoluminescence measurements showed that δ-doping can increase the lifetime …

Engineering The Ground State Of Complex Oxides, Derek Joseph Meyers

Graduate Theses and Dissertations

Transition metal oxides featuring strong electron-electron interactions have been at the forefront of condensed matter physics research in the past few decades due to the myriad of novel and exciting phases derived from their competing interactions. Beyond their numerous intriguing properties displayed in the bulk they have also shown to be quite susceptible to externally applied perturbation in various forms. The dominant theme of this work is the exploration of three emerging methods for engineering the ground states of these materials to access both their applicability and their deficiencies.

The first of the three methods involves a relatively new set …

Understanding Technology Diffusion And Spatial Accessibility In The Home Healthcare Industry, Mehmet Serdar Kilinç

Graduate Theses and Dissertations

Home healthcare is becoming an important alternative to institutionalized care. It not only reduces costs but also increases health outcomes and patient satisfaction. However, the availability and efficiency of home healthcare services need to be improved as the aging population increases in the US. Hence, understanding home healthcare utilization and access are the essential steps to develop strategies ensuring effective and sustainable services to patients.

This research aims to study two main issues in the US home healthcare system: diffusion and long-term impacts of home telehealth and potential spatial accessibility of home healthcare services. Home telehealth is a promising technology …

Capillary Electrophoresis For Analysis Of Aβ1-42 Adsorption And Photo-Crosslinking, Jennifer Lynn Kurtz

Graduate Theses and Dissertations

The accumulation of amyloid-beta (Aβ) oligomers is believed to be the driving force behind Alzheimer’s disease (AD) pathogenesis. Due to the metastable nature of Aβ oligomers, the knowledge of Aβ aggregation and accumulation is not well understood. Here, we use capillary electrophoresis (CE) and photo-induced crosslinking of unmodified proteins (PICUP) to learn about the aggregation of Aβ.

First, we explore the effect of capillary coating on Aβ1-42 protein loss using CE. The dynamic coatings tested were PHEA and 50 kDa, 2000 kDa, 5000 kDa, and 8000 kDa PEO. The covalent coating tested was PVA. The results indicated that 2000 kDa …

Characterization Of Human Muscle Extracellular Matrix, Lauren Klaire Wilson

Graduate Theses and Dissertations

The performance of extracellular matrix (ECM) biological scaffolds for the treatment of volumetric muscle loss (VML) has shown promising results with regenerating native muscle in animal models and human patients. However, the limitations of these scaffolds include non-specific characteristics based on the original parameters of the muscle that is lost and this is why our group chose to characterize human skeletal ECM. By understanding the characteristics of the native human skeletal ECM, more desired queues for the biological scaffolds being used to treat VML can be provided. Upper limb and lower limb skeletal muscles were commercially obtained, decellularized using common …

An Adaptive Large Neighborhood Search Heuristic For The Inventory Routing Problem With Time Windows, Mina Hadianniasar

Graduate Theses and Dissertations

This research addresses an integrated distribution and inventory control problem which is faced by a large retail chain in the United States. In their current distribution network, a direct shipping policy is used to keep stores stocked with products. The shipping policy specifies that a dedicated trailer should be sent from the warehouse to a store when the trailer is full or after five business days, whichever comes first. Stores can only receive deliveries during a window of time (6 am to 6 pm). The retail chain is seeking more efficient alternatives to this policy, as measured by total transportation, …

Automatic User Profile Construction For A Personalized News Recommender System Using Twitter, Shiva Theja Reddy Gopidi

Graduate Theses and Dissertations

Modern society has now grown accustomed to reading online or digital news. However, the huge corpus of information available online poses a challenge to users when trying to find relevant articles. A hybrid system “Personalized News Recommender Using Twitter’ has been developed to recommend articles to a user based on the popularity of the articles and also the profile of the user. The hybrid system is a fusion of a collaborative recommender system developed using tweets from the “Twitter” public timeline and a content recommender system based the user’s past interests summarized in their conceptual user profile. In previous work, …

Design, Fabrication, And Measurement Of A Multiple-Input Multiple-Output (Mimo) Antenna For Mobile Communication, Christopher Charles Arnold

Graduate Theses and Dissertations

This thesis presents the design, fabrication and characterization of a multiband uniplanar MIMO antenna for hand-held mobile communication devices on LTE, WLAN, and WMAN networks. The antenna design methodology combined a variety of broadbanding techniques that resulted in a single-layer hybrid monopole antenna coupled to a meander line element and parasitic structures. The 115×55×1.54 mm antenna was fabricated using an FR4 composite material and occupies only a fractional volume within the size of an average cellular phone allowing ample space to integrate with existing hardware. Characterization of the MIMO antenna included input impedance, scattering parameters and radiation pattern cross sections …

Creating Quality Metrics For The Capital Facilities Delivery Industry, Kelsey D. Lamb

Graduate Theses and Dissertations

A standard for industry-wide quality metrics, similar to safety metrics, for the capital facilities delivery industry is investigated and developed with the goal to motivate industry-wide adoption of this new quality metric program. A survey of the literature found key differences between capital facilities and other industries, mainly that other industries focus on the quality of the product while capital facilities focus on maintaining the cost and schedule of a project. Creating a framework that can be used across the industry can potentially lead to uniform improvement of quality for the entire industry. Quality is defined for the capital facilities …

Using Peptoids To Build Robust, Efficient Microarray Systems, Dhaval Sunil Shah

Graduate Theses and Dissertations

Recent studies have shown microarrays to be indispensable for various biological applications, allowing for high-throughput processing and screening of biological samples such as RNA, DNA, proteins and peptides using a small sample volume (< 1 µL). Peptoids (poly-N-substituted glycine oligomers) can be used as a substitute for antibodies as capture molecules, as well as coatings for slides in antibody microarrays. The ease of synthesis of peptoids, high customizability with desired bioactivity, and speed of synthesis allows us to build a diagnostic system with a large dynamic range that can detect biomolecules from a minimal sample size. In this study, peptoid-based antibody mimics are designed to have both structural and functional features similar to those of antibodies, including a stable constant region (scaffolding) and a variable region for protein recognition. Peptoids previously screened via combinatorial library synthesis to be specific to bind Mdm-2 (mouse double minute 2 homolog) and GST (gluthathione S-transferase), have been synthesized. The protein recognition peptoids have been conjugated to PEG (polyethylene glycol) molecules with modified end groups; an amine group on one end that allows for immobilization and orientation on the slide, and an azide group on the other end that will allow for attachment to the peptoid through “click chemistry”. The number of capture molecules printed on the slides can be increased by making the available surface area of the slide larger via coating with microspheres. We have determined that partially water soluble peptoids that are also helical, can self-assemble into microspheres. Sequences have been developed that can consistently produce uniform microsphere coatings on slides that increase the overall surface area. A high surface area corresponds to a higher number of binding sites, and therefore a more sensitive system. The work done has shown that slides may be successfully coated in order to potentially improve the detection system.

A Computational Study Of The Potential For Lng Tanker Polystyrene Foam Insulation Failure Under Fire Exposure, Jeffrey David Martinez

Graduate Theses and Dissertations

Liquefied natural gas is shipped across the oceans in large marine carriers. The carriers house the LNG using several different insulation systems. One of these systems involves large aluminum spheres insulated with polystyrene foam. Polystyrene foam is very susceptible to heat degradation. This raised issues as to the extent of possible insulation failure caused by a large ship fire. Experiments were done investigating the nature of polystyrene’s thermal degradation, notably by Brauman, Chen, and Matzinger and Butler. A large scale investigation was also performed by Sandia National Laboratory. However, computational modeling of the degradation was lacking. This work set out …

Value Focused Inland Waterway Infrastructure Investment Decisions, Othman Boudhoum

Graduate Theses and Dissertations

Maritime transportation functions as the backbone of world trade. The U.S. inland waterway transportation system is comprised of 12,000 miles of navigable waterways that connect and move freight between the global supply chain and thirty eight States. When investing in inland waterway infrastructure, we should aim to maximize all benefits associated with the investment including flood protection, water supply, hydropower generation, recreation, and environmental impact benefits. We formulate an initial qualitative value model for the inland waterway infrastructure investment decision based on a value-focused thinking approach which allows us to holistically evaluate project investment alternatives. Given limited resources, a portfolio …

Text-Independent Speaker Identification Using Statistical Learning, Alli Ayoola Ojutiku

Graduate Theses and Dissertations

The proliferation of voice-activated devices and systems and over-the-phone bank transactions has made our daily affairs much easier in recent times. The ease that these systems offer also call for a need for them to be fail-safe against impersonators. Due to the sensitive information that might be shred on these systems, it is imperative that security be an utmost concern during the development stages. Vital systems like these should incorporate a functionality of discriminating between the actual speaker and impersonators. That functionality is the focus of this thesis.

Several methods have been proposed to be used to achieve this system …

Synthesis Of Palladium And Palladium-Copper Nanostructures As Electrocatalysts, Haibin Wu

Graduate Theses and Dissertations

Pd and its alloys are alternatives of Pt as promising catalysts and electrocatalysts for many reactions. Size controlled synthesis of nanoparticles remains a major research subject, since smaller size particles show better catalytic performance. In this work, we developed a modified chemical wet method to prepare Pd and Pd-Cu nanostructures with uniform small size. Different sizes and shapes of Pd nanostructures were successfully synthesized by using the two reducing agents (i.e., L-ascorbyl-6-palmitate or phenylphosphinic acid). The reducing agents play a role to control the final morphologies and sizes of particles. The use of L-ascorbyl-6-palmitate favors to form irregular branch shapes …