Engineering Commons^™

On The Extraction Of Volatiles From Lunar Regolith Using Solar Power, Jorge Alberto Frias

Open Access Theses & Dissertations

Recent lunar missions have confirmed the presence of water and miscellaneous volatiles within the craters of the Moon's South Pole. If harvested, these resources have the potential to provide an incredible budget saving to the human space exploration program by dropping the total mass that astronauts need to carry from the Earth. The area that develops these technologies is called In-Situ Resource Utilization (ISRU). ISRU allows reducing the payload, and consequently reduces the energy consumption and cost of space exploration. The present thesis investigates methods for the extraction of volatiles from regolith within the shadowed craters of the Moon using …

Sustainable Water Management In The University Of Texas At El Paso, Cora Martinez

Open Access Theses & Dissertations

This thesis showed how to improve water and financial savings for UTEP and El Paso by improving water conservation and sustainability of the UTEP campus. The goals of this research were successfully accomplished by focusing in three principal objectives.

1. Analyze historical data of water consumption of the UTEP campus for the past decade.

2. Evaluate water consumption to quantify water consumption by buildings and type of use, as well as provide recommendations for water and cost savings.

3. Synthesize a water management framework within the UTEP Facilities' Geographic Information System (GIS) for long-term monitoring and evaluation

Evaluation Of Ozone Trends And Distribution In The Paso Del Norte Region Using Tceq's Cams Data And Ozone Data Collected At Two Supplemental Sites, Adrian Michael Sandoval

Open Access Theses & Dissertations

The purpose of this research was to determine whether the city of El Paso will continue to be in attainment if the Environmental Protection Agency (EPA) revises the National Ambient Air Quality Standards (NAAQS) of 8-hour average ozone concentration from 0.075 parts per million (ppm) to 0.070 ppm. For the duration of El Paso's ozone season, June-September 2012, two 2B Technology Ozone 202 monitors were deployed at proposed locations, not previously monitored. This was done in order to quantify concentration of ozone. In addition, ozone and meteorological data was downloaded from several Continuous Ambient Monitoring Stations (CAMS) in the Paso …

Transparent And Amorphous W-Ti-O Nano-Coatings, Gaurav Baghmar

Open Access Theses & Dissertations

The present work was performed on the Ti-doping effects in a small and controlled amount into WO3 to produce W0.80Ti0.20O3. The aim of study is to explore the effect of Titanium (Ti) coupled with growth temperature on the growth of behavior, microstructure and optical properties. W0.80Ti0.20O3 coatings were fabricated using RF magnetron sputter-deposition onto Silicon (Si-100) wafers and optical quality Quartz substrates. The depositions were made in a wide temperature ranging from room temperature (25 ˚C) to 500 ˚C. X-ray diffraction (XRD), high-resolution scanning electron microscopy (SEM), Optical spectrophotometery and Spectroscopic Ellipsometry (SE) were performed to study the effect of …

Carrier Collaborative Networks: Hybrid Hub Location Algorithms, Satyen Suresh Awale

Open Access Theses & Dissertations

Within the context of the Logistics and supply chain and management, the Hybrid Hub and Spoke system has certain complexities regarding the selection of the hub location in the supply chain facility system. The performance and efficiency of the network route selection and hub location depends upon the percentage savings that has been made by choosing the appropriate location for the hub to maintain the efficient flow of the goods within the network. Hub location selection mostly depends on the profit margins shared by the carrier, supply and demand status of the facility and amount of flow of the goods …

Comparison Study Between Fem And Sem For Wave Propagation Models Applied To Solids, Shaddy Roberto Castillo Ponton

Open Access Theses & Dissertations

Wave propagation is a field whose application has spread across many disciplines. In the field of structural engineering, wave propagation methods have focused their attention specifically in the area of structural health monitoring and active control of vibrations and noise. Likewise, the development of new methods and their application have been successful in the area of material science with a special emphasis on the field of structural integrity evaluation of anisotropic and inhomogeneous structures (laminated composite structures). The current available analysis tools are inadequate to handle the modeling of complex structures. One-dimensional wave propagation problems in solids are still a …

Development Of A Multi-Material, Multi-Technology Fdm System For Process Improvement Experimentation, David Espalin

Open Access Theses & Dissertations

Over the last three decades, developments within the area of Additive Manufacturing (AM) have resulted in novel technologies capable of producing highly customized, complex part geometries in a fraction of the lead time required by traditional manufacturing methods (e.g., injection molding, metal casting). In particular, fused deposition modeling (FDM), a material extrusion AM process, can produce parts using production-grade thermoplastics like acrylonitrile butadiene styrene, polycarbonate, and polyetherimide. Additionally, non-commercial materials (e.g., polycaprolactone, ceramic loaded polymers, carbon nanotube loaded polymers) have been processed using FDM in part to demonstrate the potential diversity in material selection.

Recently, a myriad of personal 3D …

Three-Dimensional Structural Electronic Integration For Small Satellite Fabrication, Cassie Gutierrez

Open Access Theses & Dissertations

The ability to realize truly three-dimensional electronic circuits is complicated if not impossible using traditional fabrication techniques. Such techniques are limited to the use of two dimensional printed circuit boards (PCBs), and require various dissonant processes which exhaust time, volume and cost. Due to the nature of Additive Manufacturing (AM) such problems are diminished and in some ways completely overcome. Additive Manufacturing allows for a higher range of design freedom along conformal surfaces, as well as unit level customization; it is the threshold for embedded electronics, allowing for three-dimensional circuitry in ways traditional fabrication is unfeasible. In such ways, additive …

Decision Rule Induction For Service Sector Using Data Mining- A Rough Set Theory Approach, Zhonghua Hu

Open Access Theses & Dissertations

Nowadays, data mining is more widely used than ever before; not only by the academic area, but also in the industry and business area. Apart from execution of business processes, the creation of knowledge base and its utilization for the benefit of the organization is becoming a strategy tool to compete. Despite of having ever growing data bases, the problem is that the finance company fails to fully capitalize the true benefits which can be gained from this great wealth of information. The data mining technology instead of classic statistical analysis is developed to help the people to discover the …

A Study Of Wo3 And W0.95ti0.05o3 Thin Films Using Comparative Spectroscopy, James Heyward Howard

Open Access Theses & Dissertations

Tungsten oxide (WO3) is important and well-studied in materials science, particularly for sensor applications. In this research work, we consider the innovation of adding Ti to thin films of this material. Since the characteristics of any such material are strongly dependent on the conditions and methods used in its deposition, the main objective of this project is to provide a detailed spectroscopic characterization by Raman scattering, infrared absorption, and X-ray photoelectron spectroscopy (XPS) of WO3 and of W0.95Ti0.05O3. This characterization will be based on comparison of the morphology and composition of WO3-based thin films, grown by radio frequency magnetron reactive …

Minimizing The Retransmission Delay And Energy Expense Of Arq With The Optimal Placement Of Caching Routers In A Video Communication Network, Jesus Enrique Hernandez

Open Access Theses & Dissertations

The use of intermediary caching routers to service retransmission requests was investigated in this thesis. The main goal is to reduce the expected retransmission delay in a video communication network where the capacity for intermediate caching routers is constrained. In order to reduce the retransmission delay, the effect of the placement of routers with caching ability is investigated. Moreover, as a consequence of reducing the retransmission distance, the energy spent on retransmitting video packets is reduced as well. The average retransmission delay and the average energy consumption were modeled with mathematical programs that select the optimal placement of caching routers …

Placement Of Multiple Base Stations For Energy Efficient Communication In Wireless Sensor Networks, Nagendra Kiran Kambhampati

Open Access Theses & Dissertations

In recent years, the importance of multiple base stations in Wireless Sensor Networks (WSNs) has increased in applications such as environmental, border zone control, etc. Due to the energy constraints in individual sensor nodes, extending lifetime is an essential objective in WSNs. The physical, medium access and network layers have been targeted by a number of researchers for designing energy efficient protocols. While the proposed protocols were successful in energy savings for individual sensor nodes, they fail to solve problems related to the topology of the network. An example of such problem is that sensors nodes around the base station …

Analysis Of Isolated Traffic Signal Control Systems, Petr Malina

Open Access Theses & Dissertations

Intelligent Transportation Systems (ITS) are implemented for increase of efficiency and safety in transportation. This thesis focuses on the area of traffic signal timing operations which is one of ITS components. The first objective is to compare the Czech and the U.S. methods for isolated fixed time traffic signal control, using an intersection in El Paso, Texas, as the test site. The second objective of this thesis is to evaluate the U.S. actuated isolated timing plan and compare it against the Czech and U.S. fixed time controls. A microscopic traffic simulation model of the selected intersection is coded in VISSIM …

Electrical Characterization Of Microcrystalline Lifepo4 For Application In Lithium Ion Batteries, Sukhdeep Amarjeet Labana

Open Access Theses & Dissertations

Electrical Characterization of Microcrystalline LiFePO4 for application in lithium ion batteries. Mainly, to study about the electrical properties of Lithium Iron Phosphate as a cathode material to increase its Electrical consumption.

Thin Film Growths Of Znte And Cdte On Various Substrates Using A Novel Close Space Sublimation Reactor Css4, Damian Marrufo

Open Access Theses & Dissertations

Thin films of CdTe have been grown on CdS in a variety of methods for use in thin film photovoltaic systems. Limits to the efficiency of CdTe/CdS solar cells have been attributed to defects in the lattice that occur between the interface of CdS and CdTe due to a lattice mismatch. A close space sublimation (CSS) reactor known as the CSS4 was designed and fabricated in UTEP to deposit complex layers of CdTe and ZnTe on top of a CdS film that is grown via chemical bath deposition in order to obtain a CdTe photovoltaic. Unfortunately, the original design and …

High-Order Central Finite-Volume Schemes For Atmospheric Modeling, Kiran Kumar Katta

Open Access Theses & Dissertations

Atmospheric numerical modeling has been going through drastic changes over the past decade, mainly to utilize the massive computing capability of the petascale systems. This obliges the modelers to develop grid systems and numerical algorithms that facilitate exceptional level of scalability on these systems. The numerical algorithms that can address these challenges should have the local properties such as the high on-processor operation count and minimum parallel communication i.e., high parallel efficiency. They should also satisfy the following properties such as inherent local and global conservation, high-order accuracy, geometric flexibility, non-oscillatory advection and positivity preservation properties. The goal of this …

Development Of Models To Estimate Modulus And Permanent Deformation Of Texas Bases, Eric Navarro

Open Access Theses & Dissertations

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Cryogenic System Development For Lox/ Hydrocarbon Propulsion Research, Francisco Pineda

Open Access Theses & Dissertations

A propulsion research facility is being developed at the Center for Space Exploration Technology Research (cSETR) at the University of Texas at El Paso (UTEP). These facilities were developed in order to meet new research demand for Liquid Oxygen (LOX)/Liquid methane (LCH4) experiments. The main goal of this system is to produce in-house liquid methane and supply propellants to their respective test set up in a cryogenic state. The work presented describes the design, development, and operation of a liquid methane condensation system and a cryogenic delivery feed system. The condensation system design will allow for a production of methane …

Nanoprobe I-V Characterization Of Cdte/Cds Micro And Nano-Patterned Solar Cells, Heber Prieto

Open Access Theses & Dissertations

This thesis presents a novel way to characterize micro and nano patterned cadmium telluride thin film solar cells via a nano-probe system. A historical review of CdTe-based solar cells is presented first followed by review of the technology developed to produce the patterned CdTe cells. A detailed presentation is then provided on the use of a Zyvex nanoprobing system to characterize the patterned solar cells. The I-V response of micro- and nano-patterned solar cells stimulated under different e-beam conditions is presented and analyzed. Suggestions of how to improve the technique are provided. This work documents, for the first time, the …

Identification Of Rework Station Location To Enhance Reworkability Using Design For Disassembly, Juan Alejandro Saavedra

Open Access Theses & Dissertations

Rework stations are commonly established as part of each assembly stations causing the material flow of the process to be constantly interrupted. Another option is to place the rework station at the end of the production, but this is not cost effective. This breakeven point between reworkability and cost methodology has been proposed in this thesis to identify the location of a single rework station in an assembly line in order to enhance reworkability using the Design for Disassembly (DfD) principles. The methodology uses the 17 guidelines of DfD in a manufacturing scenario in order to propose a reworkability index …

Structure Morphology And Optical Properties Of Nanocrystalline Ga2o3 Thin Films, Sampath Kumar Samala

Open Access Theses & Dissertations

Gallium Oxide thin films were produced by sputter deposition by varying the substrate temperature (T_s) in a wide range (T_s=25-800 oC) and under variable deposition time. The structural characteristics and optical properties of Ga₂O₃ films were evaluated using X-ray diffraction (XRD), scanning electron microscopy (SEM), energy-dispersive X-ray spectrometry (EDS), Rutherford backscattering spectrometry (RBS) and spectrophotometric measurements. The effect of growth temperature is significant on the chemistry, crystal structure and morphology of Ga₂O₃ films. XRD and SEM analyses indicate that the Ga₂O₃ films grown at lower temperatures were …

Evaluation Of Non-Nuclear Devices In Measuring Moisture Content And Density Of Soils, Martin Jesus Sotelo

Open Access Theses & Dissertations

The objective of this report was to assess the ability of several different devices to measure moisture content and dry density of various compacted geomaterials. The experimental research involved the testing of different subgrade soils and one base material. More than a dozen specimens, 2 ft in height and 1.5 ft in diameter, were constructed to evaluate the Transtech SDG 200, Purdue TDR, and the Decagon 10 HS moisture content sensor. The Speedy Moisture Tester and DOT600 Roadbed Water Content Meter were also evaluated using individual soil samples. All materials were tested at five different moisture contents, but at their …

Control Of A Robotic Prototype Multi-Axis Synergistic System, Julio A. Torres

Open Access Theses & Dissertations

Balance is an ability that every person has and uses in normal daily life, to walk, run, stand, dance, etc. However, there are people who suffer a kind of balance impairment. The Computerized Dynamic Posturography (CDP) is technique in balance rehabilitation, where the patient is asked to stand on a moving platform that is equipped with sensors that measure how well you maintain your balance. In this thesis, a new CDP mechatronic system, the Multi-Axis Synergistic System (MASS), for balance assessment is being developed.

As a first stage and as the objective of this research work the transferable control algorithm …

A Study Of International Wastewater Challenges And Policy In The Tijuana River Watershed, Gloria Ann Villaverde

Open Access Theses & Dissertations

Since the 1930s, untreated and undertreated sewage from Tijuana, Baja California, México has been released into the Tijuana River Watershed causing contamination of the water supply, crops, the Tijuana Estuary and California beaches. Passage of the North American Free Trade Agreement (NAFTA) has exacerbated the problem by causing population and industrial growth explosions for which there have been insufficient services to meet the needs of the people. The waters of the Tijuana River flow (from México) north over the International Border, into the Tijuana Estuary, discharge out to the Pacific Ocean and often flow north, up the California Coast; therefore, …

Modeling Power Consumption Of High Performance Computer Clusters, Mario Caire

Open Access Theses & Dissertations

This dissertation describes a utilization-based power modeling approach that makes use of the /proc file system and is applied to estimating power load and energy consumption of high performance computer clusters. A full cluster power model is specified that meets the following conditions: 1) provides accurate energy estimates; 2) consists of a minimal number of variables; and 3) the selected variables provide a sufficient degree of explanation of the primary OS level contributors to power consumption. The cluster power model is based on analysis at the system or compute-node level, where various models are developed and evaluated. All models described …

New Mathematical And Evolutionary Optimization Methods To Achieve Fair Division In Multi-Agent Resource Allocation, Emmanuel Gurrola Molina

Open Access Theses & Dissertations

The problem of resource allocation among a group of agents naturally arises in a wide range of real-life events. The subject has earned popularity across the disciplines of Economics, Computer Science, Artificial Intelligence Operations Research and Social Welfare. This resource allocation problem can be commonly referred to as Multi-Agent Resource Allocation (MARA). This work considers a MARA problem where a central agent decides to allocate a set of divisible and non-divisible goods. MARA is considered to be part of an interdisciplinary research area in which the literature is vast and rapidly developing. However, most of the available literature mainly focuses …

High Pressure Synchrotron X-Ray Diffraction Studies Of Superprotonic Transitions In Phosphate Based Solid Acids, Juan Daniel Hermosillo

Open Access Theses & Dissertations

Certain phosphate based solid acids, such as CsH2PO4 and RbH2PO4, have been shown to exhibit an abrupt, several-order-of-magnitude increase in their proton conductivity when heated above a temperature threshold. This so called superprotonic behavior allows the above-mentioned materials to function as fuel cell electrolytes at temperatures between 150C and 300C, a remarkable application that attracted significant interest especially from the automobile industry. Yet, the microscopic structures and dynamic mechanisms responsible for this behavior are not fully understood. In fact, until very recently, the very nature of the superprotonic behavior has been debate, with some groups attributing the steep proton enhancement …

Magnetic Cell Separation By Inkjet Printing For Disease Monitoring, Sylvia Lucia Natividad

Open Access Theses & Dissertations

The standard analysis technique for cell sorting, flow cytometry, requires centralized facilities such as tertiary Medical Centers. According to the U.S. Department of Health and Human Services Designated Health Professional Shortage Areas (HPSA) Statistics, in this country alone, more than 35 million people live in medically underserved areas, many of which need access to diagnostic procedures for proper management of their diseases. A cell sorting technique that can be done in low-resource settings at a decreased cost to the medical organization and the patient has been developed through this research project. By combining inkjet printing technology and magnetic labeling of …

Multi-Physics Modeling Of Induction-Based Additive Manufacturing Of Metals, Danny W. Muse

Open Access Theses & Dissertations

The shift towards 3D printing of functional products has provided a glimpse of the future in terms of manufacturing technologies and the creation of volumetrically complex structures made possible only through these technologies. 3D printing has emerged from the culmination of several technologies covering multiple industries and a myriad of materials. Unlike subtractive technologies such as mills, lathes and CNC machines, where material is removed from a bulk slab or billet to produce a desired part, 3D printing uses an additive layered approach to deposit material based on cross sections of the desired part. Both approaches produce parts based on …

Spatially Adaptive Interpolation And Super-Resolution Using The Optimal Recovery Framework, Abdul Jabeer Shaik

Open Access Theses & Dissertations

Reconstruction of missing pixels from the available Low Resolution (LR) Image pixels in order to create a High Resolution (HR) Image is a very important problem with many applications. In our research, we propose a spatially adaptive optimal recovery interpolation method for generating a discrete High Resolution Image from any given discrete Low resolution Image. This Spatially Adaptive OR approach is then extended to Super-Resolution technique.

Optimal Recovery (OR) method can be used for reconstructing signals from uniform samples. The OR framework uses the values of a given linear operator to estimate the value of a desired linear operator. The …