Engineering Commons^™

Alternatives To Piloting In Bracksih Waters: Accuracy And Precision Of Commerical Reverse Osmosis Membrane Design Model Projections, Erika Mancha

Open Access Theses & Dissertations

In a time of economic recession and drought, the Texas Water Development Board is reviewing alternatives to the current Texas Commission on Environmental Quality requirement of demonstration-scale pilot testing membrane desalination to decrease permitting costs and project construction delays. One alternative is to use engineering judgment with membrane manufacturer's software models to predict membrane performance and ensure that product water quality requirements will be met. To comply with state permitting requirements, the first few months of successful full-scale operation can be submitted in lieu of pilot demonstration.

The goal of this research is to characterize the accuracy and precision of …

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 …

The Effect Of Al, Mo, And B On The Oxidation Behavior Of Three Nb-Based Alloys, Victoria Rae Rangel

Open Access Theses & Dissertations

Extensive work has been undertaken to develop niobium based structural alloys for high temperature applications. These developments have led to the increase in engine operating temperatures and better performance efficiency. New materials including alloys based on metals with higher melting points such as molybdenum and niobium with silicon are now being examined as a better alternative to nickel base superalloys. Materials with a niobium silicide based composites have the potential for higher temperature capabilities. The oxidation behavior of Nb-20Cr-10Si and Nb-20Cr-10Si-5Al has been studied in a range of temperature from 700 to 1400°C in static air. Isothermal oxidation experiments indicate …

Investigation Of Gas-Solid Fluidized Bed With Non-Spherical Particles, Mario Alberto Ruvalcaba

Open Access Theses & Dissertations

The number of experimental and numerical studies of multiphase flows has remarkably increased over the last several years. This research has abundant applications in energy, chemical, and conversion processes. Common use of these technologies includes catalytic cracking for petroleum refineries, fluidized bed reactors (type of chemical reactor), interface modification, and has been an important technology breakthrough in coal gasification. The present work will concentrate on the investigation and validation of gas-solid flows utilizing numerical methods. The gas-solid flows study on this research assumes the solid and gas phases as continua with averaged properties.

The fluid flow computation was achieved using …

Graphene Stuctures For Energy Storage Application, Mohammad Arif Ishtiaque Shuvo

Open Access Theses & Dissertations

Energy storage devices are receiving extensive attention in recent years due to the increasing demand of energy. Super-capacitor is one of the energy storage devices with high specific power density and wide applications in electronic vehicles, commercial mobile electronics, and military devices. Carbon based materials are widely used in making Electrochemical Double Layer Capacitor (EDLC) or super-capacitor for their excellent porous nature along with their electron transport capability. By increasing the specific surface area of the porous carbon materials, specific capacitance of the super-capacitor can be significantly improved. Graphene, a newly discovered material, has been incorporated in making super-capacitor electrodes …

The Effects Of Uncommon Silicides On The Oxidation Of Alloys From The Nb-Cr-Si System, Daniel Brendan Voglewede

Open Access Theses & Dissertations

Niobium based alloys are being tapped as potential successors to current nickel base superalloys in high temperature applications. In the aerospace industry, high temperature materials are constantly being pushed to higher temperature regimes in order to improve engine efficiency however current superalloys cannot be pushed further due to melting temperature limitations. Niobium, being a refractory metal, can withstand much higher temperatures than nickel however its oxidation properties are woefully inadequate.

The purpose of this study is to ascertain whether increased silicon additions can improve niobium oxidation properties by: forming ternary silicides with better oxidation properties and by preventing the formation …

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 …

Impact Testing Of Zirconium Diboride, Mark David Flores

Open Access Theses & Dissertations

Refractory ceramic materials such as zirconium diborides (ZrB2) have been excellent candidate materials for application in turbine blades, leading edge surfaces of high mach aircraft and high temperature applications. This is due to their good strength at high temperatures (T>1800°C). But questions on their ultimate durability at such temperatures remains an issue, especially with respect to foreign object impact damage as well as oxidation. Little characterization of such materials of the impact durability of such materials at very high temperatures has been performed - In this talk an experimental approach for the impact testing of ceramic materials at elevated …

Analysis Of Particulate Matter Air Quality Impacts On Sunland Park, New Mexico Due To Dust Emissions From Puerto Anapra, Mexico Using A Complex Terrain Air Dispersion Model Calpuff, Grisel Edith Arizpe

Open Access Theses & Dissertations

The City of Sunland Park is located in Doña Ana County in southern New Mexico. The City has unusual boundaries which border not only with other communities in New Mexico but also the State of Chihuahua, Mexico to the south and the City of El Paso, Texas to the east. This area is considered part of the Paso del Norte Airshed (PdNA), which is comprised also by El Paso County, Texas and Ciudad (Cd.) Juarez, Mexico. Historically, this region has had air quality problems and compliance issues with National Ambient Air Quality Standards (NAAQS), including particulate matter and ozone pollution. …

Investigation Of A Water Desalination Method Via A Humidification-Dehumidification Process Using Hvac Technology, Juan A. Cornejo

Open Access Theses & Dissertations

Potable water is becoming a scarce resource in many arid regions of the world. An experimental unit was designed and constructed to examine and characterize the production capabilities of a humidification-dehumidification (HDH) desalination process. An HDH cycle offers a viable, technologically light, alternative for producing fresh water from brackish water because the low relative humidity air is infused with water vapor through evaporation by means of conventional heating, ventilation and air conditioning (HVAC) components. The evaporation process effectively separates salts and suspended solids from the brackish feed-water. Desalinated water is subsequently recovered by extracting the water vapor from the moist …

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 …

Designing Optimal Aviation Baggage Screening Strategies Using The Monkey Search Algorithm, Edgar Ivan Jimenez

Open Access Theses & Dissertations

This thesis addresses the aviation baggage screening design problem considering several baggage screening devices which may be used for system implementation, the devices have different false clear and false alarm rates, throughput and purchase costs. In the present research, a comprehensive cost function which not only includes the cost associated with purchase and operation of baggage security devices, but also includes the indirect costs associated with device errors is used. A new monkey search based evolutionary algorithm is presented to determine the best selection of baggage screening security devices in order to minimize the expected annual total cost. The final …

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 …

Investigation Of The Divcon Neuron To Increase The Performance Of A Traditional Feed Forward Multi-Layer Perceptron And Its Hardware Implementation, Jovan Saenz

Open Access Theses & Dissertations

ABSTRACT

Artificial Neural Networks (ANNs) have been developed in an attempt to emulate the information processing capabilities of the biological brain. They offer an alternate computing approach to problems in which mathematical modeling is complicated, such as pattern recognition and pattern classification.

Since ANNs were proposed in the early 1940s, there has been a great amount of research effort dedicated to the development of new models that improve performance. Consequently, different architectures, a variety of activation functions, and distinct learning algorithms have been developed and implemented in different disciplines such as medicine, engineering, and science. In addition, ANNs have been …

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 …

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 …

An Experimental Investigation On Lox/Lch4 Reaction Control Thrusters, Arturo Acosta-Zamora

Open Access Theses & Dissertations

This work describes the development and preliminary testing of a thrust measurement system, in combination with a propellant feed and automation controls systems to test the performance of 8.9 to 35.6 N (2 to 8 lbf) LOX/Methane reaction control thrusters. LOX/LCH4 has come to be the main focus of next generation "green" propellants for future space exploration. As there is limited experience with this propellant combination, an effort is being conducted to research performance of rockets using these propellants. The development of a thrust measurement, propellant feed, and automation controls systems is necessary for proper testing and qualification of thruster …

Bod5 And Cod Data Analysis From The Northwest And Robert R. Bustamante Wastewater Treatment, Juan Carlos Adame

Open Access Theses & Dissertations

The objectives of this thesis are to explore the use of basic Statistical Process Control in a Wastewater Treatment Plant with secondary treatment. Additionally, to describe statistical behavior and review normality of some reportable parameters, also to analyze mainly parameters like BOD5 (Biological Oxygen Demand), Electrical Conductivity, and COD (Chemical Oxygen Demand) with seasons of the year and days of the week, using data from the Northwest (NW) and Robert R. Bustamante (RRB) Wastewater Treatment Plants from El Paso Texas.

The scope of this analysis is to understand how Statistical Process Control can help to predict peak and valleys of …

Combustion And Compaction Of Lunar Regolith/Magnesium Mixtures, Armando Delgado

Open Access Theses & Dissertations

Feasible techniques that require low energy consumption and reduced costs are of vital importance to enable humans to explore and occupy space. In-Situ Resource Utilization (ISRU) is the branch in the Human Exploration Technology that studies the production of consumables and materials using indigenous lunar and planetary resources. ISRU represents an enabling opportunity for establishing long lasting human exploration missions. Construction materials produced in-situ are of special interest because of the high payload they represent when launching them from Earth. The in-situ production of construction materials that requires low energy input would be advantageous due to the limited energy in …

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 …

Modeling Large-Truck Involved Crashes: An Econometric Modeling Framework, Mouyid Islam

Open Access Theses & Dissertations

This research aims to analyze large-truck involved crashes (i.e., having a gross vehicle weight rating more than 10,000 pounds) through the application of advanced econometric modeling techniques--namely, random parameter models (i.e., tobit regression, mixed logit). To achieve this, various national and state specific data sets are analyzed with the goal to provide an improved understanding of the complex interactions of contributing factors (e.g., factors related to drivers and occupants, vehicle, and road-environment) influencing large-truck crashes. Additionally, the modeling techniques considered in this research account for possible unobserved effects related to the data. The aforementioned econometric techniques provide an analytical foundation …

Reverse Osmosis Permeate Post-Treatment By Upflow Calcite Contactors: Dissolution And Mass Transport, Luis Demetrio Maldonado-Castaneda

Open Access Theses & Dissertations

Reverse osmosis (RO) desalination may be used for desalination of brackish and saline waters, but the product water may have low concentrations of hardness and alkalinity, which may corrode infrastructure. Adjustment of pH and addition hardness and alkalinity may be required to meet potable water guidelines. Upflow calcite contactors may be used instead of lime or caustic addition for post-treatment of RO permeate to deliver non-blended, stable, non-corrosive finished water.

The first objective of this research was to experimentally determine the sensitivity of performance of upflow calcite contactors with respect to several design and operational parameters such as: feed pH, …

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

Development Of Advanced Polymer Nanocomposite Capacitors, Miguel Mendoza

Open Access Theses & Dissertations

The current development of modern electronics has driven the need for new series of energy storage devices with higher energy density and faster charge/discharge rate. Batteries and capacitors are two of the most widely used energy storage devices. Compared with batteries, capacitors have higher power density and significant higher charge/discharge rate. Therefore, high energy density capacitors play a significant role in modern electronic devices, power applications, space flight technologies, hybrid electric vehicles, portable defibrillators, and pulse power applications. Dielectric film capacitors represent an exceptional alternative for developing high energy density capacitors due to their high dielectric constants, outstanding breakdown voltages, …

Hafnia-Based Nanostructured Thermal Barrier Coatings For Next Generation Gas Turbine Technology, Mohammed Noor-A-Alam

Open Access Theses & Dissertations

Extensive efforts have been directed in the last several decades towards improving thermodynamic efficiency of industrial gas turbines for power generation plants. The central theme of the efforts is to increase the turbine operating temperature and, thus, allowing higher efficiency. Thermal barrier coatings (TBC) constitute an advanced technology to protect the metallic surface from high temperature exposure for long time operation. The TBCs protect the gas turbine components from high temperature and allows further increase in engine operating temperature which subsequently increases the efficiency of the gas turbine power plant. However, the current TBC materials are capable of allowing the …

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 …

Numerical Analysis Of Single Tank Thermocline Thermal Storage System For Concentrated Solar Power Plant, Samia Afrin

Open Access Theses & Dissertations

The overall efficiency of a Concentrating Solar Power (CSP) plant depends on the effectiveness of Thermal Energy Storage (TES) system. A Single tank TES system has potential to provide effective solution. In a single tank TES system, a thermocline region, which produces the temperature gradient between hot and cold storage fluid by density difference, is used. Preservation of this thermocline region in the tank during charging and discharging cycles depends on the uniformity of the velocity profile at any horizontal plane. One of the major challenges for the single tank thermocline is actually maintaining the thermocline region in the tank, …

Applications Of Density Functional Theory In Materials Science And Engineering, Manuel Alvarado

Open Access Theses & Dissertations

Density Functional Theory (DFT) is a powerful tool that can be used to model various systems in materials science. Our research applies DFT to two problems of interest. First, an organic/inorganic complex dye system known as a Mayan pigment is modeled to determine chemical binding sites, verifying each model with physical data such as UV/Vis spectra. Preliminary studies on palygorskite-based mayan pigments (mayacrom blue, mayacrom purple) show excellent agreement with experimental studies when using a dimer dye geometry binding with tetrahedrally-coordinated aluminum impurity sites in palygorksite. This approach is applied to a sepiolite-based organic/inorganic dye system using thioindigo attached to …

Selection Of Sustainable Rigid Pavement Using The Mechanistic-Emperical Pavement Design Guide, Laith Ali Al Sabty

Open Access Theses & Dissertations

A new pavement design guide called "Mechanistic-Empirical Pavement Design Guide (ME-PDG)" has been developed for design and rehabilitation of pavements. The guide uses general characteristics, traffic, environmental conditions, and pavement structure information to estimate pavement life. ME-PDG is a comprehensive program which requires significant number of inputs and time to analyze and predict pavement performance.

In El Paso, Texas most of the urban highways are constructed as Continuously Reinforced Concrete Pavement (CRCP). Although commonly placed, the design life of CRCP pavements is rarely realized. In addition, the cost of constructing CRCP is significantly higher than the Jointed Plain Concrete Pavement …