Engineering Commons^™

Hardware Development And Testing For Lox/Lch4 Rocket Engine, Pedro Nunez

Open Access Theses & Dissertations

The University of Texas at El Paso (UTEP) Center for Space Exploration and Technology Research (cSETR) has focused its research efforts on developing LOX/LCH4 propulsion systems. As part of the Janus Sub-orbital vehicle program, UTEP is developing a 2000 lbf throttleable rocket engine (Chrome X). The first iteration of this engine design will be geared for further optimization towards a flight engine. Components like electric motors, valves, and sealants have been selected to achieve throttle ability and sealing of the engine. These components play a crucial part on the engine to be able to have a successful firing. As part …

Compressive Vector Reconstruction: Hypothesis For Blind Image Deconvolution, Alonso Orea Amador

Open Access Theses & Dissertations

Alternative imaging devices propose to acquire and compress images simultaneously. These devices are based on the compressive sensing (CS) theory. A reduction in the measurement required for reconstruction without a post-compression sub-system allows imaging devices to become simpler, smaller, and cheaper. In this research, we propose a new algorithm to compress and reconstruct blurred images for CS imaging devices. Blur effect in images is common due to relative motion, lens, limited aperture dimensions, lack of focus, and/or atmospheric turbulence. Our intention is to compress a blurred image with CS techniques and then reconstruct a blur-free version using the proposed algorithm. …

Automatic Patch Classification And Diffusion In Adaptive, Luis Alonso Ponce

Open Access Theses & Dissertations

Multi-Frame image restoration is a form of Super-Resolution (SR) which consists of combining multiple Low-Resolution (LR) images in order to reconstruct a single High Resolution (HR) image. In this Thesis we improved a spatially-adaptive SR scheme, based on the framework of Optimal Recovery (OR), whereby the block-by-block processing is done based on the properties of the corresponding local LR image data patches. The bandwidth parameter is adapted based on the local variance of each corresponding block from all LR images that contribute to the HR image block to be reconstructed. Also, an optimal regularization parameter needs to be chosen for …

A Cubesat Communication System Development For Gto Mission, Ashiqur Rahman

Open Access Theses & Dissertations

Tracking, telemetry and command (TT&C) systems on traditional small satellites have advanced significantly in last few decades. The capabilities, requirements and expectations of the communication system have been increased significantly for the smaller satellites. Small satellites are now performing the tasks near to the bigger satellites which increases the dependency on the communication system in terms of reliability and data management. This Thesis paper will focus on development of the communication system of a 1U cube Satellite named Orbital Factory II (OFII). The satellite will be launched into a geostationary transfer orbit (GTO) onboard a United Launch Alliance (ULA) Atlas …

Flexible Analysis Of Creep Rupture Database And Accelerating The Acquisition Of Creep Rupture Data, Christopher Ramirez

Open Access Theses & Dissertations

A comprehensive statistical analysis of creep data is a difficult task because there are many layers of uncertainty for a given dataset. Sources of uncertainty are inherent in both the databases that provide data, and the data themselves. Additionally, creep rupture predictions made with time-temperature parameter (TTP) models add an additional layer of uncertainty due to the fundamentally different ways in which each TTP model predicts creep behavior. A set of guidelines from the ECCC currently exist for such analyses, but they are best suited for narrowly-defined datasets. In this study, a broader set of guidelines are developed to analyze …

Safety Airway For Small Unmanned Aerial Vehicles Using A Gas Particles Behavior Analogy, Pablo Rangel

Open Access Theses & Dissertations

The United States Federal Aviation Administration (FAA) implemented the Part 107 legislation to allow the flight of Unmanned Aerial Vehicles (UAV) for commercial use (i.e. package deliveries, power transmission line inspections, etc.) in the National Airspace System (NAS). As a consequence of the newly introduced rules, there is an increased risk for accidents involving injured bystanders or damaged to property. The work within this document defines a UAV to UAV safety distance model that acts as a range sensor enabled "elastic bubble". The length of the UAV safety bubble contracts and expands upon changing airway wind speed conditions. It also …

Three Dimensional Finite Element Model For Residual Stresses In Parts Manufactured By Slm And Ebm, Jesus Gerardo Reyes Schuldes

Open Access Theses & Dissertations

Ongoing research efforts in industry and academia have a focus on optimal build parameters that lead to suitable mechanical properties with minimum defects in parts manufactured by powder bed fusion additive manufacturing technologies, such as Electron Beam Melting (EBM) and Selective Laser Melting (SLM). Additional and significant resources, including energy, time, and money are spent as a result of obligatory post-manufacturing heat and/or mechanical treatment to ensure optimum mechanical properties. One intrinsic fault in these technologies, which contributes to the need for treatment processes after part fabrication, is the creation of residual stresses during these processes. Residual stresses remain in …

Risk Mitigation In The Supply Chain Caused By Multitple Phase-In And Phase-Out Components Using Simio Simulation, Anabel Renteria Marquez

Open Access Theses & Dissertations

Manufacturing is constantly changing, adapting to new technologies and making improvements on their products design, while dealing with engineering design changes can represent an improvement or savings to the company it can also end up as a huge risk of disruption in the Supply Chain if there is not a safety phase-in and phase-out components transition because the network became more complex and affected processes needs to be revalidated, here comes the importance to set up an strategy to mitigate any possible risk and maximize total revenue.

A case study for a two tiers level Supply Chain system is evaluated …

The Former Asarco Demolition Fallout, A Post Study On Lead Soil Concentrations And Environmental Agents Of Redistribution In El Paso, Texas, Stephanie A. Robinson

Open Access Theses & Dissertations

The former El Paso ASARCO Smelting and Refining Co. operated between 1877 and 1999, the pyrometallurgic activity was estimated to have discharged excess of a 1,000 tons of lead (Pb) into the atmosphere from 1969-71. It was estimated 96 tons of (Pb) were emitted on an annual basis from the standing ore and fluid beds. The Environmental Protection Agency (EPA) determined that lead (Pb) is the heavy metal of the highest concentration within the vicinity of the smelter. After the smelter production ceased, flash flooding common to the southwest, such as the 2006 historic flood, increased transportation of superficial contaminants …

Microelectromechanical Systems Inertial Measurement Unit As An Attitude And Heading Reference System, Francisco Javier Salcedo Ortega

Open Access Theses & Dissertations

Microelectromechanical systems inertial measurement units (MEMS IMU) are an accessible technology that can be used as an attitude and heading reference system (AHRS); they are low cost and functional enough to be used in many Inertial Navigation Systems (INS). However, the gyroscope component on the IMU tends to severely drift over time without the use of filtering or other navigation systems reference such as a Global Positioning System (GPS) device. This Thesis is focused on working with a variety of IMUs to describe the accuracy, precision, and error propagation. It also works as an introductory guide to the world of …

Pyroelectric Ceramics As Temperature Sensors For Energy System Applications, Jorge Luis Silva

Open Access Theses & Dissertations

Temperature is continuously monitored in energy systems to ensure safe operation temperatures, increase efficiency and avoid high emissions. Most of energy systems operate at high temperature and harsh environments to achieve higher efficiencies, therefore temperature sensing devices that can operate under these conditions are highly desired. The interest has increased in temperature sensors capable to operate and in harsh environments and temperature sensors capable to transmit thermal information wirelessly. One of the solutions for developing harsh environment sensors is to use ceramic materials, especially functional ceramics such as pyroelectrics. Pyroelectric ceramics could be used to develop active sensors for both …

Optimization Of Neural Network Architecture For Classification Of Radar Jamming Fm Signals, Alberto Soto

Open Access Theses & Dissertations

Radar jamming signal classification is valuable when situational awareness of radar systems is sought out for timely deployment of electronic support measures. Our Thesis shows that artificial neural networks can be utilized for effective and efficient signal classification. The goal is to optimize an artificial Neural Network (NN) approach capable of distinguishing between two common radar waveforms, namely bandlimited white Gaussian jamming noise (BWGN) and the ubiquitous linearly frequency modulated (LFM) signal. This is made possible by creating a theoretical framework for NN architecture testing that leads to a high probability of detection (PD) and a low probability of false …

Raman Microscopic Analysis Of Internal Stress In Boron-Doped Diamond Thin Films, Emma M.A. Sundin

Open Access Theses & Dissertations

The correlations between induced stress on undoped and boron-doped diamond (BDD) thin films, sample chemical composition, and fabrication substrate are investigated in this study via confocal Raman microspectroscopic analysis. Stability of BDD films is relevant to fast-scan cyclic voltammetry, as film delamination and dislocation of BDD-coated electrodes that can occur during neurosurgical electrode implantation can negatively impact the biosensing reliability of this technique. Electrodes were fabricated by coating cylindrical tungsten rods using a custom-built chemical vapor deposition reactor. The results of the analysis reveal a direct correlation between regions of pure diamond and enhanced material stress, as well as preferential …

Structural And Electrical Characterization Of Tin Oxide Resistive Switching, Arka Talukdar

Open Access Theses & Dissertations

Resistive switching in metal oxide is a phenomenon in which the metal oxide changes its resistance upon application of electric field and thus giving two states; high resistance state (HRS) and low resistance state (LRS). Many metal oxides have been investigated however very little is known about unipolar resistive switching in SnO2 though it has shown excellent resistive switching characteristics. Defects in the material play a vital role in resistive switching of the metal oxides. In this work, the role of defects in resistive switching of SnO2 are investigated in Ti/SnO2/Au structures. Two methods were used to control the concentration …

Redesign Of A Volume Adjustable Transtibial Prosthetic Socket, Samuel Terrazas Quezada

Open Access Theses & Dissertations

Recent research and development in prosthetics have aimed at improving socket designs and components to mimic more efficiently the human body. One such innovation is the Aperture Socket, a low-cost volume adjustable prosthetic socket. During the validation stage of its development, the Aperture Socket successfully demonstrated that it could compensate for volume changes, but various improvements on use and comfort were identified. This project develops and tests a redesign of the Aperture Socket previously developed for amputees in developing countries and subsequently patented and licensed to LIMBS International, Inc.

The first phase of this study was the creation of various …

The Design, Construction And Operation Of System To Analyze The Decomposition Gases Of Af-M315e, Jonathan Alejandro Valenzuela Brok

Open Access Theses & Dissertations

With the current trend of aerospace organizations towards developing green monopropellant, the key priority is to eliminate the use of highly dangerous monopropellants, such as hydrazine. In that vein, one of the best candidates to replace hydrazine is a monopropellant known as AF-M315E. AF-M315E was developed by the Air Force and is currently being advanced by NASA and private corporations for use on various satellite platforms, with NASA looking to launch a test satellites part of their Green Propellant Infusion Mission (GPIM), Raytheon providing support on the Missile Defense Agency's Network Centric Airborne Defense Element (NCADE) program and Department of …

Design Optimization For Heat Dissipation In Polymer Additive Manufacturing With Joule Heating, Tania Alejandra Ventura

Open Access Theses & Dissertations

Nowadays, the use of additive manufacturing (AM) is mainly focused on the production of prototypes with the purpose of evaluating a design. This industry has become a subject of constant reinvention; in fact, an emerging application of AM is focused on creating parts with embedded electronics. However, the development of both traditional and additive manufactured electronics has led to an increase in power densities and size reduction. Consequently, thermal management has become essential in electronics, as overheating decreases reliability of the component leading to a premature failure.

In this study, a polycarbonate component design with integral electrical circuitry that is …

Comprehensive Finite Element Modeling Of Ti-6al-4v Cellular Solids Fabricated By Electron Beam Melting, Edel Arrieta

Open Access Theses & Dissertations

Additive manufacturing permits the fabrication of cellular metals which are materials that can be highly customizable and possess multiple and extraordinary properties such as damage tolerance, metamorphic and auxetic behaviors, and high specific stiffness. This makes them the subject of interest for innovative applications. With interest in these materials for energy absorption applications, this work presents the development of nonlinear finite element models in commercial software platforms (MSC Patran/Nastran) that permit the analysis of the deformation mechanisms of these materials under compressive loads. In the development of these models, a detailed multiscale study on the different factors affecting the response …

Image Data Mining For Quality Control Of Nanofiber Reinforced Piezoelectric Nanocomposites Based On Sem Images, Zhonghua Hu

Open Access Theses & Dissertations

Recently, portable and wireless nano-scaled devices have been widely used in environmental monitoring, medical implants, defense technology, industrial safety, and personal electronics, such as the nanowire-based gas and chemical sensors and programmable nanowire circuit for nano-processors. There has been an increasing demand for high energy density capacitors that can be engineered for various applications in advanced devices. In it, piezoelectric nanofiber materials play critical role in producing new products. A piezo-ceramic polymer composite contains a polymer of high dielectric strength and high permittivity ceramic inclusions, making it well suited as a high energy density capacitor. Furthermore, the research shows that …

Renewable Energy Systems Optimization Using Monte Carlo Simulation And Evolutionary Algorithms, Nicolas Lopez

Open Access Theses & Dissertations

This Dissertation explores the Renewable Energy Integration Problem, and proposes a Genetic Algorithm embedded with a Monte Carlo simulation to solve large instances of the problem that are impractical to solve via full enumeration. The Renewable Energy Integration Problem is defined as finding the optimum set of components to supply the electric demand to a hybrid

microgrid. The components considered are solar panels, wind turbines, diesel generators, electric batteries, connections to the power grid and converters, which can be inverters and/or rectifiers. The methodology developed is explained as well as the combinatorial formulation. In addition, 2 case studies of a …

Axial Ratio Correction For Gnss Antennas In Asymetrically Coupled Environments, Adam Narbudowicz, Max Ammann, Dirk Heberling

Conference Papers

The paper demonstrates a technique to correct the axial ratio of dual-fed circularly-polarized antennas in the presence of strong coupling with surrounding components or asymmetrically reduced ground plane. It demonstrated - based on a standard GPS L1 patch antenna - that for certain situations a phase shift of up to 135° may be beneficial compared to the routinely used 90°, allowing for AR improvement from 7.8 dB (for 90°) to 2.1 dB (135°).

Performance Degradation Analysis Of Aviation Hydraulic Piston Pump Based On Mixed Wear Theory, C. Zhang, S. Wang, M. Tomovic, L. Han

Engineering Technology Faculty Publications

This paper focuses on the mathematical modeling of axial piston pump through dividing the failure development of friction pair into lubrication, mixed lubrication and abrasion. Directing to the wedge-shaped oil film between cylinder block and valve plate, the support force distribution under the temperature variance was obtained. Considering the rough peak of valve plate, the contact load model is built under plastic deformation and elastic deformation and the corresponding wear volume is calculated. Computing the wear and tear along the counter-clockwise, the total amount of friction and wear can be calculated. Simulation and preliminary wear particle monitoring test indicates that …

Power Budgets For Cubesat Radios To Support Ground Communications And Inter-Satellite Links, Otilia Popescu

Engineering Technology Faculty Publications

CubeSats are a class of pico-satellites that have emerged over the past decade as a cost-effective alternative to the traditional large satellites to provide space experimentation capabilities to universities and other types of small enterprises, which otherwise would be unable to carry them out due to cost constraints. An important consideration when planning CubeSat missions is the power budget required by the radio communication subsystem, which enables a CubeSat to exchange information with ground stations and/or other CubeSats in orbit. The power that a CubeSat can dedicate to the communication subsystem is limited by the hard constraints on the total …

Institutionalizing Continuous Improvement Plan In An Engineering Technology Department- Closing The Loop, Alok K. Verma, Stephanie G. Adams, Cheng Y. Lin, Nestor Escobales, Isaac L. Flory Iv

Engineering Technology Faculty Publications

Continuous improvement is a corner stone of a quality engineering or engineering technology program. Accreditation Board of Engineering and Technology requires that a well-planned and implemented continuous improvement plan should be in place. The ABET 2015-16 Criterion 4 Continuous Improvement1 states: "The program must regularly use appropriate, documented processes for assessing and evaluating the extent to which the student outcomes are being attained. The results of these evaluations must be systematically utilized as input for the continuous improvement of the program. Other available information may also be used to assist in the continuous improvement of the program." A successful continuous …

A Mobile Platform Using Software Defined Radios For Wireless Communication Systems Experimentation, Otilia Popescu, Shiny Abraham, Samy El-Tawab

Engineering Technology Faculty Publications

A distinctive feature of wireless communication systems is implied by the fact that there is no physical connection between the transmitter and its corresponding receiver, which enables user mobility. However, experimenting with wireless communication systems is mostly done in the lab, where transmitters and receivers are setup on benches, in stationary settings. This prevents students from experiencing fading and other propagation effects associated with mobile wireless channels. This paper describes a mobile platform for wireless communication experimentation that enables students to run experiments beyond the confines of a traditional lab, in realistic settings that cover indoor and outdoor scenarios with …

Semi-Analytical Approach For Time-Dependent Load-Settlement Response Of A Jacked Pile In Clay Strata, Lin Li, Jingpei Li, De'an Sun, Weibing Gong

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

Mechanical behavior of the soil around a jacked pile changes significantly during pile installation and subsequent consolidation. Hence, an axially loaded jacked pile exhibits apparent time-dependent bearing performance after pile installation. This paper presents a semi-analytical approach to predict the time-dependent bearing performance of an axially loaded jacked pile in saturated clay strata. The effects of pile installation and subsequent consolidation on the changes in mechanical properties of the surrounding soil are modeled by the cavity expansion theory and the radial consolidation theory, respectively. An exponential function-based load-transfer (t-z) curve is employed to describe the nonlinear behavior of the pile-soil …

Imaging Of Super-Fast Dynamics And Flow Instabilities Of Superconducting Vortices, L. Embon, Y. Anahory, Ž L. Jelić, E. O. Lachman, Y. Myasoedov, M. E. Huber, G. P. Mikitik, A. V. Silhanek, M. V. Milošević, A Gurevich, E. Z. Zeldov

Physics Faculty Publications

Quantized magnetic vortices driven by electric current determine key electromagnetic properties of superconductors. While the dynamic behavior of slow vortices has been thoroughly investigated, the physics of ultrafast vortices under strong currents remains largely unexplored. Here, we use a nanoscale scanning superconducting quantum interference device to image vortices penetrating into a superconducting Pb film at rates of tens of GHz and moving with velocities of up to tens of km/s, which are not only much larger than the speed of sound but also exceed the pair-breaking speed limit of superconducting condensate. These experiments reveal formation of mesoscopic vortex channels which …

Dynamic Transition Of Vortices Into Phase Slips And Generation Of Vortex-Antivortex Pairs In Thin Film Josephson Junctions Under Dc And Ac Currents, Ahmad Sheikhzada, Alex Gurevich

Physics Faculty Publications

We present theoretical and numerical investigations of vortices driven by strong dc and ac currents in long Josephson junctions described by a nonlinear integro-differential equation which takes into account nonlocal electrodynamics of films, vortex bremsstrahlung, and Cherenkov radiation amplified by the attraction of vortices to the edges of the junction. This work focuses on the dynamics of vortices in Josephson junctions in thin films where the effects of Josephson nonlocality are essential but London screening is negligible. We obtained an exact solution for a vortex driven by an arbitrary time-dependent current in an overdamped junction where the vortex turns into …

Cryogenic Rf Test Of The First Srf Cavity Etched In An Rf Ar/Cl2 Plasma, J. Upadhyay, A. Palczewski, S. Popovic, A.-M. Valente-Feliciano, Do Im, H. L. Phillips, L. Vuskovic

Physics Faculty Publications

An apparatus and a method for etching of the inner surfaces of superconducting radio frequency (SRF) accelerator cavities are described. The apparatus is based on the reactive ion etching performed in an Ar/Cl₂ cylindrical capacitive discharge with reversed asymmetry. To test the effect of the plasma etching on the cavity rf performance, a 1497 MHz single cell SRF cavity was used. The single cell cavity was mechanically polished and buffer chemically etched and then rf tested at cryogenic temperatures to provide a baseline characterization. The cavity's inner wall was then exposed to the capacitive discharge in a mixture of …

Attitudes Towards Face-To-Face Meetings In Virtual Engineering Teams: Perceptions From A Survey Of Defense Projects, Lawrence R. Blenke, Abhijit Gosavi, William Daughton

Engineering Management and Systems Engineering Faculty Research & Creative Works

Modes of communication used in virtual defense projects have changed dramatically over the years with tools such as email and video-conferencing dominating face-to-face (FTF) meetings. We conducted a survey at a defense firm with an aim to test current attitudes towards FTF meetings – with respect to significant problems faced, project success, transfer of technical requirements, preference for FTF vis-à-vis virtual meetings, differences between virtual and co-located environments, criticality of various forms of communication, and whether FTF meetings were scheduled as often as desired. Our survey participants, about one hundred in number, were experienced engineers, technicians, and program managers – …