Engineering Commons^™

Improving The Engineering Properties Of Pla For 3d Printing And Beyond, Carmen R. Rocha

Open Access Theses & Dissertations

Additive manufacturing (AM), now more commonly known as 3D printing, has been classified as efficient, fast, and practical in the prototyping sector of product development. In the work presented here, we will use one of the AM techniques known as Material extrusion 3D printing (ME3DP), which has all the advantages of AM. However, one of the biggest challenges facing ME3DP technologies is the limitation of the range of materials used by this technique. Acrylonitrile butadiene styrene (ABS) and poly-lactic acid (PLA) are currently the most common thermoplastics materials used in ME3DP because of their ability to melt and be reprocessed. …

Computational Modeling Of A 60kw Oxy-Methane Direct Power Extraction Combustor, Omar Daniel Vidana

Open Access Theses & Dissertations

ANSYS Fluent was used to optimize components of a direct power extraction combustor. This includes the fuel injector, nozzle, and cooling units. Changes in the injector's inlet location impacted pressure and velocity distribution. An angle of 115 degrees with respect to the x-axis was found to increase distribution efficiency. Temperature and velocity data from the combustor and nozzle were calculated using NASA CEA and Fluent. Magnitudes of temperature and velocity for CEA and Fluent matched within 9% and 4%, respectively. For the cooling system it is expected that cavitation will not occur since the saturation temperature of water is not …

Treatment Of Dissolved Metals For Direct Potable Reuse, Cesar Alberto Alvarez

Open Access Theses & Dissertations

In the process of direct potable reuse (DPR), the bulk of the removal of dissolved metals removal is accomplished by reverse osmosis. This treatment is especially important in wastewater containing contaminants from industrial processes. The goal of this research was to evaluate the performance of DPR with respect to the removal of salinity and dissolved metals to meet drinking standards. Samples were collected from the El Paso Water Utilities Advanced Water Purification pilot system throughout various points in the treatment process. The samples were analyzed for their concentration of ions with Ion Chromatography (IC) and dissolved metals using an Inductively …

Characterization Of High Intensity Turbulent Flows Through Time Resolved Particle Image Velocimetry In A Backward Facing Step Combustor, Martin De La Torre

Open Access Theses & Dissertations

The fundamental understanding of turbulent premixed combustion has taken place as one of the major research topics of interest in industry thanks to advancements in kHz level laser diagnostics such as in Particle Image Velocimetry (PIV) and Planar Laser Induced Fluorescence (PLIF). Because of said advancements in this technology researchers and the scientific community are now able to expand their understanding of flame studies at high turbulence conditions to acquire a better understanding, and improve models used in turbine design, scram/ram jets, rocket engines, and emissions control. This surge of new technologies has made this topic a high priority one …

Damage Tolerance And Assessment Of Unidirectional Carbon Fiber Composites, Mark David Flores

Open Access Theses & Dissertations

Composites are beginning to be used in a variety of different applications throughout industry. However, certification and damage tolerance is a growing concern in many aerospace and marine applications. Although compression-after-impact have been studied thoroughly, determining a damage tolerance methodology that accurately characterizes the failure of composites has not been established. An experimental investigation was performed to study the effect of stacking sequence, low-velocity impact response, and residual strength due to compression and fatigue. Digital Image Correlation (DIC) captured the strains and deformation of the plate due to compression. Computational investigations integrated non-destructive techniques (C-Scan, X-Ray) to determine the extent …

Combining Interval And Probabilistic Uncertainty In Engineering Applications, Andrew Martin Pownuk

Open Access Theses & Dissertations

In many practical application, we process measurement results and expert estimates. Measurements and expert estimates are never absolutely accurate, their result are slightly different from the actual (unknown) values of the corresponding quantities. It is therefore desirable to analyze how this measurement and estimation inaccuracy affects the results of data processing. There exist numerous methods for estimating the accuracy of the results of data processing under different models of measurement and estimation inaccuracies: probabilistic, interval, and fuzzy. To be useful in engineering applications, these methods should provide accurate estimate for the resulting uncertainty, should not take too much computation time, …

Wettability Of Magnesium Based Alloys, Victor Manuel Ornelas

Open Access Theses & Dissertations

The premise of this project was to determine the wettability behavior of Mg-based alloys using three different liquids. Contact angle measurements were carried out along with utilizing the Zisman method for obtaining values for the critical surface tension. Adhesion energy values were also found through the use of the Young-Dupre equation. This project utilized the Mg-based alloy Mg-2Zn-2Gd with supplemented α-Minimum Essential Medium (MEM), Phosphate Buffer Saline solution (PBS), and distilled water. These three liquids are commonly used in cell cultivation and protein adsorption studies. Supplemented α-MEM consisted of α-MEM, fetal bovine serum, and penicillin-streptomycin. Mg-2Zn-2Gd was used because of …

Stem Cell Induction Via Inkjet-Mediated Gene Transfection, Gilbert Paquian Jr.

Open Access Theses & Dissertations

In 2009 and 2011, it was shown that micropores in the cell membrane that form during inkjet cell printing are a potential vector for gene transfection1,2. These papers showed that porcine aortic endothelial cells and Chinese hamster ovary cells were coprinted with green fluorescent protein-coding (GFP) plasmids onto collagen or gelatin "biopaper" substrates. Printed cells showed a viability of ~90% with transfection efficiencies ranging from 2-30%1,2. Using inkjet-mediated gene transfection (IMGT) to insert a plasmid coding for the Yamanaka stem cell induction factors, it may be possible to offset common drawbacks of the induction process, such as low efficiency, throughput, …

Optimal Energy Management System For A Net Zero Building Using Multi-Agent Systems Approach, Arzhang Ghassemi Pashakalaei

Open Access Theses & Dissertations

Buildings have a significant impact on energy usage and the environment. Much of the research in architectural sustainability has centered on economically advanced countries because they consume the most energy and have the most resources. However, sustainable architecture is important in developing countries, where the energy consumption of the building sector is increasing significantly. The aims of this Thesis are investigating using the hybrid system, which formed by interconnecting two source of renewable energy as solar (PV arrays) and wind (turbine) along with city grid for compensation purposes wherever it is required. In this Thesis, after literature review, we consider …

Application Of Secondary Analyses On Industrial Data Sets, Luis G. Perez

Open Access Theses & Dissertations

Secondary analysis on quantitative data sets is the in-depth analysis of relationships, trends, patterns or behaviors that are not obvious from a superficial examination of data but that can be very germane in the application of that data. The present work presents a framework for investigators to use in applying secondary analysis on big data that correlates to the research topic. The framework can facilitate the illumination of possible data behaviors or patterns that could be useful in arriving at an answer to a question. Behavior of monitored equipment (analyzers, meters, etc.) can easily be depicted and can be used …

Evaluation Of Point Of Use Reverse Osmosis Systems For Drinking Water In Colonias, Oscar Daniel Ramirez

Open Access Theses & Dissertations

Clean drinking water is often considered a right and not a privilege, especially in first world countries. However, thousands of residents of colonias (settlements in the U.S. that lack access to basic infrastructure) struggle to obtain clean drinking water, including some in the Paso del Norte Region. Residents of colonias located in Doña Ana County, NM, and El Paso County, TX typically rely on domestic wells and hauled water, respectively, but these sources may be of inadequate quality, potentially posing a health risk due to microbiological contamination, presence of arsenic, or elevated concentration of total dissolved solids. This project brings …

Microstructural Characterization Of High Velocity Oxy Fuel Coatings Of Inconel 718 And Iron Aluminides, Ana Cecilia Rios Ibanez

Open Access Theses & Dissertations

Thermal spray guns are used today to deposit metallic powders as homogeneous and durable coatings with low porosity onto metals. The objective is to improve their wear resistance and their corrosion resistance in order to withstand conditions such as abrasion and erosion. This can improve the life of turbines, generators and such devices in environments found in ultra-supercritical coal-fired (AUSC) boilers, steam turbines and gas turbines (Mohammed & Cabrera, 2014). Industries like manufacturing, automobile and especially in the sustainable energy area, have used this technique to improve component characteristics, extend product life, increase performance as well as reduce production and …

An Effective And Optimal Quality Control Approach For Green Energy Manufacturing Using Design Of Experiments Framework And Evolutionary Algorithm, Juan Alejandro Saavedra

Open Access Theses & Dissertations

Quality Control (QC) and Quality Assurance (QA) strategies vary significantly across industries in the manufacturing sector depending on the product being built. Such strategies range from simple statistical analysis and process controls, decision-making process of reworking, repairing, or scraping defective product. This study proposes an optimal QC methodology in order to include rework stations during the manufacturing process by identifying the amount and location of these workstations. The factors that are considered to optimize these stations are cost, cycle time, reworkability and rework benefit. The goal is to minimize the cost and cycle time of the process, but increase the …

Development And Testing Of Oxygen/Methane Torch Igniter Technologies For Propulsion Systems, Luis Eduardo Sanchez

Open Access Theses & Dissertations

The development and testing of an oxygen/methane torch ignition system as well as the evaluation process of the system are presented with the purpose of characterizing the properties and performance of methane as a fuel in a propulsion system. The experimental approach to this Dissertation entails the development and testing of a swirl torch igniter under conditions that may be seen when feeding propellant from the main storage tanks: combinations of gaseous and liquid oxygen and methane. The experimental goal of this Dissertation is to display the range of operability of the igniter technology presented leading to stable and consistent …

Investigation On Pyroelectric Ceramic Temperature Sensors For Energy System Applications, Md Rashedul Hasan Sarker

Open Access Theses & Dissertations

Temperature monitoring for energy generation systems plays an important role for control of overall safety and efficiency. To operate the energy system at optimum operating conditions, it is important to measure the real time temperature. Furthermore, harsh environment temperature sensing is desired since most sensors in energy systems are exposed to high temperature, high pressure, and corrosive environments. There is an increasing demand of wireless sensor networks and major interest in energy system applications for harsh environment and remote sensing applications. For this study, LiNbO3 and Pb(Zr0.52Ti0.48)O3 (PZT) pyroelectric ceramic materials were used to develop temperature with wired and wireless …

Removal Of Iron, Zinc, And Copper From Waters Impacted By Acid Mine Drainage Using Natural Zeolite, Mackayla Janae Thyfault

Open Access Theses & Dissertations

In this research, the adsorption behavior of zeolites with respect to iron (Fe), zinc (Zn), and copper (Cu) has been studied in order to assess its application to heavy metal removal in polluted settings caused by acid mine drainage (AMD). The St. Cloud zeolitic deposit used in this project was characterized using a sieve analysis; the effective diameter and coefficient of uniformity were calculated. Batch studies were performed, and the samples were analyzed using ICP-OES. Batch studies used metal concentrations ranging from 50 mg/L to 650 mg/L. Freundlich, Linear, Langmuir, and BET adsorption isotherms were applied and evaluated to the …

Using Zeolite For Soil Moisture Retention And Salinity Control, Mark Torres

Open Access Theses & Dissertations

There is a great need in the desert southwest United States for exploring ways to save water in agriculture as it accounts for up to 90 percent of water consumption in many western states (USDA 2016). As surface water reaches critical lows the dependence on ground water has increased leading to the need for deeper wells with higher salt concentrations. The studies conducted for this research included using zeolites from the St Cloud Mining Company in Winston, New Mexico to determine the feasibility of using these zeolites to help and retain moisture in zeolite treated soils. The Volumetric Water Content …

Digital Processes And Characterization For Fabricating 3d Rf Devices, Harvey Hing Tsang

Open Access Theses & Dissertations

In this work, co-planar waveguides (CPW) are fabricated and characterized with low temperature 3D printed materials for flexible electronic applications. Laser processing is introduced to reduce heating and cooling times for curing and subtractive manufacturing. CPWs are optimized by varying printing resolution, adjusting curing conditions and shaping conductor profile with a pico-laser. By using acrylonitrile butadiene styrene (ABS) as substrate material and Dupont CB028 as conductive material, a high S21 and low S11 CPW is fabricated. Optimized direct write methods are dispensed onto 3D complex structures to move away from 2.5D style printing and move into true 3D printed antenna …

A Multi-Objective Sustainable Model For Transportation Asset Management Practices, Marketa Vavrova

Open Access Theses & Dissertations

Transportation Asset Management (TAM) practices have gained popularity in the United States and worldwide with the aim to provide the required level of service for the transportation infrastructure network in the most cost-effective manner. However, TAM is a complex decision-making process because many objectives and different perspectives, often producing conflicting goals, must be considered.

This Dissertation presents a Multi-Objective Sustainable (MOS) model to integrate economic, social, and environmental sustainable objectives into TAM decision-making. The objective is to develop a holistic multi-objective asset management approach integrating environmental and social sustainability related performance measures with traditional indicators, such as asset condition and …

Cdte Doped With Zn Grown On Si(111) And Si(211) Using The Closed Space Sublimation Method, Jose Alberto Valdez

Open Access Theses & Dissertations

Cadmium telluride (CdTe) doped with zinc (Zn) has been used for the fabrication of X-ray imaging devices. CdTe allows the device to have the same image quality at a lower X-ray dose. When silicon is used as a substrate for CdTe growth, this reduces the cost and allows the readout circuitry to be fabricated on the same substrate. However, material quality and device performance needs to be addressed since the lattice parameters of CdTe (6.482 Å) and Si (5.431 Å) result in a 19% lattice mismatch.

In this work, CdTe doped with Zn is deposited on Si (211) and Si …

Molecular Dynamics Proxy Applications For Optimizing Performance Of Simulations Under Extreme Conditions, Jayalath Abeywardhana Mudiyanselage Madawa Abeywardhana

Open Access Theses & Dissertations

Exascale performance of scientific application is a prominent goal for the scientific community and computer hardware vendors. As a result, several proxy applications for the widely used scientific codes have been developed with the purpose of testing performance, memory and power consumption issues associated with simulations at the exascale. Co-MD is a proxy application for classical Molecular Dynamics (MD) codes based on the (SPaSM) Los Alamos code.

This work comprises two different but related computational aspects: performance evaluation and optimization of Co-MD (Co-Design Molecular Dynamics) for different computer architectures/execution models, and direct application of SPaSM (Scalable Parallel Short-range Molecular Dynamics) …

Information Entropy Measures Applied To Hierarchial Complex Technical And Socio-Technical Systems, Satya Aditya Akundi

Open Access Theses & Dissertations

A significant increase of Systems-of-Systems (SoS) is currently observed in the social and technical domains. With increasing constituent components, Systems of Systems are becoming larger and more complex. Recent research efforts have highlighted the importance of identifying innovative statistical approaches for analyzing complex systems to better understand how they work. This research is aimed towards developing an Information Entropy based framework to analyze complex technical and social systems. Entropy in terms of information theory can be seen as the expected amount of information observed in an event. A parallel can be drawn between information entropy and system complexity, where, as …

Dielectric Prism Antenna, Jose Antonio Avila

Open Access Theses & Dissertations

3D printing is revolutionizing the development and manufacturing of devices. Currently multi-material 3D printing, like metals plus dielectrics, is in the early stages and not very accessible. This work set out to develop an all-dielectric antenna that could be 3D printed with current widely accessible 3D printing technologies. The antenna developed is an all-dielectric ultra-thin antenna with a simple geometry. The antenna radiates by using total internal reflection and a circulating mode operating as a leaky whispering gallery mode. We are calling the antenna the dielectric prism antenna because it acts like an optical prism. The dielectric prism antenna was …

Effects Of Fabrication Conditions On Mechanical Properties Of Ti-6al-4v Fabricated By Powder Bed Fusion Additive Manufacturing, Paola Azani

Open Access Theses & Dissertations

At the writing of this Thesis, additive manufacturing (AM) also known as 3D printing, has been popularized for its diversity in applications ranging from home and personal use, medical, industrial, consumer products, aerospace, architecture, automotive, military, fashion, food, art and more. Industries taking advantage of the design freedom and complexity offered by AM have exploded the growth of the technologies. Specifically, technologies that process metals using electron and laser beams have been recognized by the aerospace industry as a promising avenue for re-engineered components leading to reduced weight and improved engineering efficiencies for components like engine brackets and nozzles. However, …

High Fidelity Localization And Sensing For Cattle Analytics, Luis Carlos Bañuelos Chacon

Open Access Theses & Dissertations

Global beef production is projected to reach approximately 60 million tons in 2015 and opportunities to increase efficiencies are significant with recent advancements in remote sensing. By economically monitoring the location and conditions of a herd such as feeding patterns, body temperature, heart rate, and other biometric information, the herd performance can now be enhanced through data-driven optimization. Next generation sensors provide high fidelity data on a wide range of measurable properties, and simultaneously, the wide adoption of these sensor systems in many consumer applications is leading to commoditization and reduced cost due to the associated economies of scale. Deploying …

Environmenal Impact Assessment And Removal Of Endocrine Disrupting Compounds In Municipal Wastewater Treatment, Juan C. Bezares-Cruz

Open Access Theses & Dissertations

The presence of compounds of emerging concern (CECs) such as endocrine disrupting compounds (EDCs) and herbicides in municipal wastewater present environmental challenges because conventional treatment systems were not designed to remove such compounds. The removal of Bisphenol-A (BPA), 17?-Estradiol (E2), 17β-Ethinylestradiol (EE2), nonylphenols (NP), and select herbicides and pesticides were investigated in two municipal wastewater treatment plants (WWTP) in El Paso, TX. In addition, the environmental impact of the two municipal wastewater treatment plants was investigated, including the theoretical addition of UV/H2O2. The use of UV/H 2O2 was studied in a UV bench scale pilot unit, and its performance was …

Through-Thickness Reinforcement For Woven Laminates, Alejandra G. Castellanos

Open Access Theses & Dissertations

Fiber reinforced polymer composites have gained popularity in aerospace and naval applications due to their tailorable mechanical properties and high strength-to-weight. Despite these advantages, between the layers of fabric (laminas), there is a resin-rich region known as interlaminar region, with no reinforcement which is very susceptible to damage. Different types of reinforcements have been tested for the interlaminar region. However, all of these methods have proved to decrease the in-plane properties due to damage to the fibers. In this Thesis, a new reinforcement technique with ZnO nanowires is proposed to increase the damage resistance. This Thesis describes the design, manufacturing …

Manufacturing And Characterization Of Energetic Materials, Carlos Alberto Catzin

Open Access Theses & Dissertations

Few products take several years of research effort to be synthesize yet disintegrate in scarcely millionths of a second when used. Despite their short lifespan energetic materials, particularly high explosives, are in demand as never before by the Aerospace, Defense, Energy, Gas, Mining, and Oil Industry for their unique properties. One class of high explosives known as polymer bonded explosives (PBXs) are popularly used in a wide variety of applications ranging from solid rocket propellants to the main explosive charge in conventional ammunitions. A key characteristic behind the popularity of PBXs in comparison to other high explosives is their handling …

Reliable And Secure Scada Framework For Residential Microgrid Communications, Goutham Krishna Chalamasetty

Open Access Theses & Dissertations

Cyber security is one of the major needs for electric power industry like many other industries and organizations. The advancements in technology provide numerous benefits to power industry as well as benefits cyber attackers to perform different cyber-attacks on the industry. Power system is a complex physical entity that deals with power generation, distribution, and transmission. In general, no individual or company or an organization can bear a one hour power cut, which shows the need for reliability in electric power industry.

In order to develop a reliable and secure Supervisory Control and Data Acquisition (SCADA) communication network, this Thesis …

Estimating Air Pollution Concentrations Using Moves-Generated Site-Specific Traffic Emissions, Mayra Consuelo Chavez

Open Access Theses & Dissertations

The research presented here attempts to estimate air pollution concentrations using MOVES and site-specific traffic emissions particularly those emissions surrounding three different air-monitoring stations. The objectives of this research include using MOVES capability to conduct project-level analyses, choosing impact zones to create emissions inventories. Emissions inventories provided by the MOVES model for impact zones within the El Paso county area were used to identify a relationship between air monitoring stations' measured results and emission estimates from a project-level analysis. The research hopes to identify an optimum zone radius that can be used to compare MOVES estimates with air monitoring stations …