Engineering Commons^™

Uav Parameter Estimation Through Machine Learning, Andres Enriquez Fernandez

Open Access Theses & Dissertations

Parameter identification of Unmanned Aerial Vehicles (UAV) is very helpful for understanding cause-effect relationships of physical phenomenon, investigating system performance and characteristics, fault diagnostics, control development/tuning, and more. Traditional ways of performing parameter identification involve establishing a mathematical model that describes the system's behavior. The equations in the model contain parameters that are estimated indirectly from measured flight data. This parameter identification process requires knowledge of the physics involved. Also, it necessitates a careful consideration of the aircraft instrumentation for accurate measurements. It also requires careful design of the flight maneuvers to ensure thorough excitation of the flight dynamics involved. …

Effect Of Temperature On A Piezoelectric Mass Flow Rate Sensor Signal, Lyan Eduardo Gutierrez Hernandez

Open Access Theses & Dissertations

On this research, we are trying to demonstrate that a piezoelectric flow sensor made of PZT can produce a higher and fluctuating signal when exposed to elevated temperatures presented on the system. This type of application can be beneficial for systems that involve changes in temperature such as compressors and be able to predict certain situations presented on those systems that can be catastrophic, that is the case for surge and stall. Therefore, a system capable of going from 25â?°C-90â?°C was designed where a piezoelectric sensor was inserted at a specific location to analyze the signal produced by these changes …

Development Of Recepticals And Joints For Embedded Electronic Components Inserted During Print Via Hybrid Thermoplastic-Based Additive Manufacturing, Leonardo Isaac Gutierrez Sierra

Open Access Theses & Dissertations

The use of hybrid additive manufacturing (AM) systems is a novel approach in the fabrication of multi-functional parts. 3D printed electronics are an example of multi-functional parts fabricated using the Foundry Multi3D System, a hybrid AM system. Previous research has demonstrated the capabilities of the system by manufacturing RF antennas and satellite panels with embedded electronics, to name a few. However, research to identify design clearances and establish a manufacturing process plan had not been performed. The purpose of this manuscript is to determine the correct clearances for foreign components to be inserted unto a partially printed substrate. Besides this …

Mechanical Performance Of Ebm Ti-6al-2sn-4zr-2mo Influenced By The Effects Of Different Hot Isostatic Pressing Treatments, Miguel Lopez

Open Access Theses & Dissertations

Electron Beam Melting (EBM) is an additive manufacturing process that presents a lower level of internal defects in comparison to Selective Laser Melting (SLM). Pairing Hot Isostatic Pressing (HIP) with Additive Manufactured metal parts, sub-surface voids can be eliminated through high pressure and temperature. This significantly improves fatigue life, impact toughness, creep, rupture strength, and tensile ductility. In this investigation, Ti-6Al-2Sn-4Zr-2Mo samples manufactured in the Arcam's Q20 system will be tested as per ASTM E8 Standard Test Methods for Tension Testing of Metallic Materials. Different variants of Hot Isostatic Pressing (HIP) treatments were analyzed and compared. Tensile testing was performed …

Planar Motion Control Of A Cube Satellite Using Cold Gas Thrusters, Christian Lozoya

Open Access Theses & Dissertations

This Thesis presents a mathematical model developed for the computational simulation ofCubeSat movement using four thrusters that permit uniaxial translation and rotation. Arbitrary functions are fit to boundary conditions to simulate the force, acceleration, velocity, and displacement of the CubeSat along a plane. The model is used to derive a motion control algorithm assuming constant pressure and mass. A single model describes both translation and rotation. This Thesis also explores the relationship between propellant consumption and the time required to complete a displacement implied by the model.

Development Of An Automated Ultrasonic Wire Embedding Process For Use With Material Extrusion Additive Manufacturing And Rapid Electronics Fabrication, Nikki L. Martinez

Open Access Theses & Dissertations

Polymers have been used in Additive Manufacturing (AM) by many industries for rapid prototyping. Parts created using polymer AM however are known to be relatively expensive thus limiting them to small volume production and making them inapplicable for mass production, while their inherent porous and anisotropic properties make them mechanically inferior to parts made using traditional methods such as injection molding. As projects demand more efficient designs, and at the same time ask for more complex features, AM, combined with other manufacturing processes, like Ultrasonic Wire embedding, can streamline and consolidate assemblies. In the realm of composite and multifunctional assemblies, …

Performance Measure Methodology Of Project Management Practices In Local Government Agencies, Johanes Johanes Makahaube

Open Access Theses & Dissertations

Local government agencies have adopted project management practices to deliver public work projects. The agencies need to measure project management performance to ensure the consistency, control, and monitoring of the project delivery process. However, local government agencies have not adopted a systematic method to measure the organization's project-management performance. At present, there is a gap regarding methods to measure project management performance in delivering construction projects. This study aims to assist local government agencies in improving their project management processes by implementing a comprehensive methodology to assess project management's performance. This dissertation is organized into three major chapter-papers: the first …

Design Of Experiments Analysis Of Powder Removal Methods For Ebm Manufactured Ti-6al-4v Parts, Luis Cesar Ramos Castañeda

Open Access Theses & Dissertations

Additive Manufacturing is a technology that allows the on-demand manufacturing of complex geometries that cannot be fabricated through traditional subtractive manufacturing methods. Powder Bed Fusion is one of the seven categories of Additive Manufacturing with two subcategories, the Laser Beam Melting and the Electron Beam Melting. Freedom of design, rapid prototyping, and customization are some of the benefits that this technology provides. Like any technology, there are limitations for each category and subcategory. The Electron Beam Melting uses the electron beam to pre-heat the powder bed, reducing the temperature difference between the build part and powder bed, causing the surrounding …

Performane Characterization Of Stabilized Materials In Pavement Foundations, Mohammad Rashidi

Open Access Theses & Dissertations

Cementitious Stabilization has been widely used to improve the strength and durability of granular materials for the construction and rehabilitation of pavement structures. Improved mechanical properties and durability of the stabilized materials combined with relatively low cost makes it an attractive method for design engineers. Although this technique appears simple and straight forward, engineering properties of individual soils and aggregates may alter widely due to heterogeneity in soil composition, difference in micro structure among soils, heterogeneity of geologic deposits and differences in chemical interactions of water with soil particles. These differences necessitate the comprehensive study in order to provide the …

Impact Of Cryptococcus Neoformans Polysaccharide Capsule On Astrocytes, Yeon Hwa Woo

Open Access Theses & Dissertations

Cryptococcus neoformans is a neurotropic, opportunistic, encapsulated, yeast-like fungus that causes life-threatening meningoencephalitis in both healthy and immunocompromised individuals. C. neoformans infects 1,000,000 people and causes 210,000 deaths worldwide annually, mostly in sub-Saharan Africa. The polysaccharide capsule of C. neoformans is the fungus major virulent factor. Glucuronoxylomannan (GXM), the main component of the capsule is abundantly released into brain tissue during C. neoformans infection, causing immunosuppressive defects in the host. C. neoformans is inhaled from the environment, disseminate via bloodstream, and crosses the blood brain barrier (BBB) to cause cryptococcal meningoencephalitis (CM). Although CM causes significant mortality in HIV/AIDS patients, …

Machine Learning Analysis To Characterize Phase Variations In Laser Propagation Through Deep Turbulence, Luis Fernando Rodriguez Sanchez

Open Access Theses & Dissertations

The present Dissertation is focused on the analysis of the atmospheric conditions of a turbulent environmental system and its effects on the diffraction of a laser beam that moves through it. The study is based on the optical communication of two labs placed at the summit of two mountains located in Maui, Hawaii. The emitter system is located at the Mauna Loa mountain and the receiver at the Haleakala. The distance between both mountains is 150 km. The emitter system is at a height of 3.1 km and the receiver at 3.4 km. The maritime environment at the location experiences …

Investigation Of Iron Doped Gallium Oxide (Ga-Fe-O) System: Structure Property Relationship And Performance Evaluation For Optical And Catalytic Applications, Swadipta Roy

Open Access Theses & Dissertations

From September 2012 to May 2015, a phenocam monitored the seaward edge of a protected mangrove forest. Calculated GCC revealed seasonal greening patterns of a mangrove species, Rhizophoa apiculata, and an overall increase in the GCC, suggesting mangrove expansion. In comparing temperature and precipitation effects, it was found that this particular mangrove species had a greening optima at temperatures between 28°C and 28.5°C, and greening and canopy development response lag time of 10 weeks in response to precipitation. Tree saplings were monitored and showed to grow by 50%, mostly during a three month period during the rainy season. The establishment …

Photovoltage Enhancement For Stable Perovskite Solar Cells With A Temperature-Controlled Grain Growth Technique, Luis Eduardo Valerio

Open Access Theses & Dissertations

By performing strong characterizations methods, one can begin to fully understand the chemistry and composition behind a great performing perovskite solar cell. Understanding how the interaction between layers inside a solar cell is driven by the temperature and overall environment is a key element to improve the fabrication process and overall efficiency of such cells. This Thesis will present a study of the hybrid organic-inorganic, mixed-cation, mixed-halide, temperature and thickness-controlled perovskite solar cell. A constant power conversion efficiency (PCE) ranging between 15-17% and an open circuit voltage V¬oc above 1.05 V for a wide-band gap perovskite cell is presented.

Design Of A Linerless Cryogenic Propellant Tank For A Small Payload Launch Vehicle, Itzel Adriana Torres

Open Access Theses & Dissertations

The need of lightweight launch vehicles that will reduce the cost and make flights more frequent into orbit has called for an increase of composite materials in the aerospace industry. Composite material’s low thermal conductivity, high resistance to fatigue, and most importantly, low-weight can greatly reduce the cost of launch operations by decreasing the overall weight of the vehicle. Weight and cost savings are critical because any amount of weight that is saved can be directly applied as an additional amount of payload capability. The tanks on space vehicles are pressurized vessels that store fuel at cryogenic temperatures and have …

Synthesis And Advanced Manufacturing Of Polymer Structures And Their Composites, Bethany Rose Wilburn

Open Access Theses & Dissertations

The following research work performed embodies three unique studies of polymer structures and their composites. In general, polymers are viscoelastic, insulative materials that are used for a wide variety of applications within industrial, aerospace, and biomedical fields. Polymers have been studied and optimized for any particular use by chemically synthesizing unique micro-structures, altering the physical properties through fabrication and post-processing, and utilizing 3D printing to achieve complex geometries. In the past decade, additive manufacturing (AM) has drawn extensive attention across academia, industry, and government agencies. It offers unprecedented advantages such as design freedom, rapid prototyping, and customization. In this work, …

Additive Manufacturing Of Engineered Material Systems For Energy Applications, Luis Angel Chavez

Open Access Theses & Dissertations

Despite increasing efforts to use renewable electricity generation techniques in the last couple of decades, the world is still heavily reliant on traditional power generation techniques. This creates the need to make such systems cheaper and less pollutant through improvements to their efficiency. Increasing the efficiency and reliability of energy conversion systems, specially those based on combustion processes has been of interest for many years. However, material limitations have brought these systems to a stagnant condition.

A novel approach to help increase the efficiency of such systems is to closely monitor their operating conditions and therefore be able to increase …

A Probabilistic Creep Constitutive Model For Creep Deformation, Damage, And Rupture, Md Abir Hossain

Open Access Theses & Dissertations

The structural analysis of Industrial Gas Turbine (IGT), Aeroengine, Gen IV nuclear components under in-service conditions at various stress and temperature are susceptible to time-dependent creep deformation and creep induced failure. Such failure phenomena are exacerbated by the randomness in material properties, oscillating loading conditions, and other sources of uncertainty. The demand for physically based probabilistic creep modeling is highly sought by alloy designers. The objective of this study is to develop and validate a probabilistic creep-damage model incorporating multi-sources of uncertainty to replace the traditional deterministic and empirical decision-based modeling. In this study, the deterministic Sine-hyperbolic (Sinh) creep-damage model …

Evaluation And Modeling Of Electrodialysis For High-Recovery Brackish Water Desalination, Shahrouz Jafarzade Ghadimi

Open Access Theses & Dissertations

This research investigates the feasibility of desalination of brackish water with electrodialysis (ED), using laboratory testing and mathematical modeling. Several experiments were performed to characterize ion-specific transport and to evaluate tradeoffs between salinity removal and specific energy consumption. A 200 cm2 Ameridia ED stack was used to perform desalination experiments with real brackish groundwater from the Kay Bailey Hutchison desalination plant in El Paso, Texas, and the results showed limiting current density of 160 A/m2 for 5 cm/s. A higher conductivity reduction was observed for flow velocity of 5 cm/s compared to 13 cm/s. Ion transport selectivity (based on relative …

Evaluation Of Cyclo Olefin Polymer As Sabot Material For High-Density Projectiles, Estebanne Tarango

Open Access Theses & Dissertations

Assuring the integrity of spacecraft and its occupants are a priority in the field of space exploration. Micrometeoroids and orbital debris are one of the primary threats that affect spacecraft materials due to the high kinetic energies involved with hypervelocity impacts. Improvement of projectile launching capabilities prompts the investigation of adequate materials for the manufacturing of sabots able to carry high-density projectiles without catastrophic failure. Polycarbonate (PC) has been the chosen material by the Hypervelocity Team at White Sands Test Facility for sabots on the 0.50 caliber launcher; however, there is a material constraint when the projectile becomes significantly dense …

Design And Operability Of A Pressurized Oxy-Combustion System, Mehrin Chowdhury

Open Access Theses & Dissertations

Fossil fuel powers more than two-thirds of the world’s electricity, a significant share of which is derived from coal power plants. Despite coal being an abundant and energy-rich fuel, the major halt to its progress is greenhouse gas emissions. Greenhouse gases are detrimental to the environment. The search for clean fossil fuel leads to the oxy-combustion process. Oxy-fuel combustion produces sequestrable carbon dioxide as exhaust. Pressurization makes carbon capture more accessible and more energy-efficient. Pressurized oxy-combustion cycles can achieve theoretically high thermal efficiencies along with a 90% carbon capture rate. Additionally, the high energy density allows smaller turbomachinery and save …

The Study Of Non-Permanent Tattoo Ink Using Nano Silver Compounds And Untact 3d Printing Technology, Jisu Lee

Open Access Theses & Dissertations

Due to a recent epidemic of COVID 19, the possibility of 3D tattoo printing technology using the Internet of Things (IoT) control system developed in a non-face-to-face contact process was identified. A non-surgical tattoo process and hygiene safety differentiated with silver tattoo ink was used to solve the health problems arising from the surgical tattoo process and to identify 3D tattoo printing techniques through a non-personal contact concept. During the tattoo processing, the image selected by the customer is sent to a designated printer via an IoT control system in a separate location. A piston-type extruder (PTE) printing technique was …

Testing The Reliability And Flexibility Of Digitizers Adapting The Rf/If Signals Over Ip Applications Using A Testbed Platform, Jose Carlos Sandoval

Open Access Theses & Dissertations

As physical constraints can be challenging for Radio Frequency (RF) telemetry, a new solution has been exploited to support the demand for RF transmissions. As frequency spectrum gets crowded with more technologies, a solution to a reliable transmission is needed. Digitizers can mitigate many of the physical constraints in order to achieve a successful RF transmission. The method includes the conversion of the RF signals to be sent over IP networks, transmit and de-convert the signal. IP networks will mitigate many disadvantages over a regular signal transmission. The authority in charge to allocate frequency bands is the Federal Communications Commission …

Brian Valdez - Dynamics And Control Of A 3-Dof Manipulator With Deep Learning Feedback, Brian Orlando Valdez

Open Access Theses & Dissertations

With the ever-increasing demands in the space domain and accessibility to low-cost small satellite platforms for educational and scientific projects, efforts are being made in various technology capacities including robotics and artificial intelligence in microgravity. The MIRO Center for Space Exploration and Technology Research (cSETR) prepares the development of their second nanosatellite to launch to space and it is with that opportunity that a 3-DOF robotic arm is in development to be one of the payloads in the nanosatellite. Analyses, hardware implementation, and testing demonstrate a potential positive outcome from including the payload in the nanosatellite and a deep learning …

Segmentation And Registration Based Automatic Cancer Proton Treatment Analysis, Yang Zhang

Open Access Theses & Dissertations

Due to its low side effects, proton therapy is rapidly developing around the world. However, the time and labor it takes to deliver the treatment have prevented widespread use in the clinic setting. For this reason, an automatic proton treatment analysis system is needed to improve efficiency during the treatment process.

The challenge lies in improving the accuracy and speed of the current proton treatment analysis system. The Range shifter correction factor is considered the same value under any given condition in our treatment system. This approximate algorithm limits the accuracy of the proton treatment analysis system. In addition, medical …

Compressive And Rheological Deformation Analysis Of Large Area Pellet-Fed Material Extrusion 3d Printed Parts In Relation To In Situ Thermal Imaging, Eduardo Meraz Trejo

Open Access Theses & Dissertations

In large area pellet extrusion additive manufacturing, the temperature of the substrate just prior to the deposition of a new subsequent layer has an effect on the overall structure of the part. Warping and cracking occur if the substrate temperature is below a specific threshold, but also deformation and deposition adhesion failure occur if the substrate temperature is above a certain threshold just prior to deposition of a new layer. Currently, Big Area Additive Manufacturing (BAAM) machine users mitigate this problem by trial and error, which is costly and may result in decreased mechanical properties, monetary losses and time inefficiencies. …

Assessment Of Point Of Use (Pou) Systems For Reducing Health Risks Associated With Drinking Water Along The U.S.-Mexico Colonias In The Paso Del Norte Region, Varinia Viridiana Felix Parra

Open Access Theses & Dissertations

In the Paso del Norte Region along the U.S. Mexico Border, there are more than 5,000 families living in impoverished communities known as colonias that lack access to basic infrastructure services such as a public water system. These depend on hauling trucks that deliver water into their storage tanks. Water storage practices by colonia residents on both sides of the border pose an enormous risk for waterborne disease outbreaks and heavy metal contamination because the water quality can decrease rapidly due to volatilization of the residual chlorine, intrusion of rainfall and air-laden dust. Since connection to centralized water treatment and …

Cradle To Grave Lifecycle Process Analysis For Transuranic Waste Management Los Alamos National Laboratory, Cesar Enrique Dominguez

Open Access Theses & Dissertations

Amid World War II, in the late 1930s, nuclear fission was discovered. This revolution gave way to the development of nuclear technologies, including the world's first atomic bomb; these advancements in nuclear research left behind radioactive waste. Radioactive waste is known as the byproduct of nuclear reactors, fuel processing plants, hospitals, nuclear research facilities, as well as the result from the decommissioning and dismantling of radiation-exposed buildings and materials. This byproduct may be dangerous to workers, the public, and the environment and must, therefore, be handled with utmost safety. Given this, radioactive waste must be processed, stored, and disposed of …

Development And Environmental Testing Of A Single-Axis Printer Inside A 1u Cubesat For On-Orbit Servicing Repairs In Low Earth Orbit, Perla Rocio Perez

Open Access Theses & Dissertations

As additive manufacturing is becoming an established technology in space, new emerging strategies improve the efficiency of the printing processes. Orbital Factory 2 (OF-2) is a small satellite-or CubeSat-developed at the University of Texas at El Paso (UTEP) which launched to space on November 2019. In January 2020, it will be released in low earth orbit (LEO). OF-2 is a 1U (10x10x10cm) CubeSat that carries a one-axis printer experiment as its primary payload. This printer was developed and tested in-house. The experiment focuses on printing electrically conductive ink on a printing circuit board that verifies the conductivity on the trace …

Thermal/Mechanical Analysis And Development Of A 2000 Lbf Liquid Oxygen/Liquid Methane Rocket Engine, Marissa Garcia

Open Access Theses & Dissertations

The Center for Space Exploration and Technology Research (cSETR) is developing three rocket engines: a 5 lbf reaction control engine, a 500 lbf engine, and a 2000 lbf engine. All these engines utilize a liquid oxygen and liquid methane propellant combination. The reason methane was selected for the fuel is because methane is easy to store, is self-pressurizing, and readily available. There is also the possibility of creating methane on planets such as Mars through an electrolysis process on the ice water found on Mars.

The 2000 lbf engine, or the CROME-X, is a modular, steady-state pintle injector engine. It …

Microstructure Evolution Of Chalcogenide Materials Via Molecular Dynamics, Sharmin Abdullah

Open Access Theses & Dissertations

The properties of a material are defined by its granular microstructure which is determined by its grain evolution and the types of grain boundaries present in the structure. For example, the performance of Cadmium Sulfide/Cadmium Telluride (CdS/CdTe) solar cells can be affected by the presence of grain boundaries which makes the study of grain structure evolution a very important part of solar cell performance optimization. Grain boundary mobilities are important properties in material science and engineering as they determine grain structures under given processing and operating conditions.

In this thesis, several computational tools were used to analyze the formation and …