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Segmentation And Registration Based Automatic Cancer Proton Treatment Analysis, Yang Zhang May 2019

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 …


Computer-Aided Classification Of Impulse Oscillometric Measures Of Respiratory Small Airways Function In Children, Nancy Selene Avila Jan 2019

Computer-Aided Classification Of Impulse Oscillometric Measures Of Respiratory Small Airways Function In Children, Nancy Selene Avila

Open Access Theses & Dissertations

Computer-aided classification of respiratory small airways dysfunction is not an easy task. There is a need to develop more robust classifiers, specifically for children as the classification studies performed to date have the following limitations: 1) they include features derived from tests that are not suitable for children and 2) they cannot distinguish between mild and severe small airway dysfunction.

This Dissertation describes the classification algorithms with high discriminative capacity to distinguish different levels of respiratory small airways function in children (Asthma, Small Airways Impairment, Possible Small Airways Impairment, and Normal lung function). This ability came from innovative feature selection, …


Cmas/Volcanic Ash Infiltration Performance Of Yttria Rich-Zirconia Thermal Barrier Coatings Produced By Electron Beam Physical Vapor Deposition, Juan Jose Gomez Chavez Jan 2019

Cmas/Volcanic Ash Infiltration Performance Of Yttria Rich-Zirconia Thermal Barrier Coatings Produced By Electron Beam Physical Vapor Deposition, Juan Jose Gomez Chavez

Open Access Theses & Dissertations

For many years the use of thermal barrier coatings (TBC) in gas turbine engines has allowed a significant increase in engine operating temperatures which are above the Ni-based super alloys' melting point. The base material for TBCs is the state of the art 7 wt % yttria stabilized zirconia (YSZ) which provides the thermal protection. Current industry demands for increased engine efficiency has pushed TBCs to the limits where significant technological constrains have been identified. One of the main ones represents the high temperature corrosion of the TBC material due to the ingestion of silicate based airborne particles commonly referred …


The Design And Testing Of A 500 Lbf Liquid Oxygen/Liquid Methane Engine, Manuel Jesus Herrera Jan 2019

The Design And Testing Of A 500 Lbf Liquid Oxygen/Liquid Methane Engine, Manuel Jesus Herrera

Open Access Theses & Dissertations

The development of liquid oxygen/liquid methane (LOX/LCH4) propulsion systems has recently become a topic of interest ever since this particular propellant combination was determined to be a suitable candidate for use in space exploration, more specifically missions to Mars. This propellant combination is unique because the propellants can be synthesized from local resources on Mars, a process called In-situ Resource Utilization (ISRU). ISRU would allow for spacecrafts to be lighter and/or increase its payload capacity to Mars-bound missions because the vehicle would not have to store the propellants required for the voyage back to earth.

For this reason, The University …


Understanding Of Deformation And Fracture Behavior In Next Generation High Strength-High Ductility Steels, Venkata Sai Yashwanth Injeti Jan 2019

Understanding Of Deformation And Fracture Behavior In Next Generation High Strength-High Ductility Steels, Venkata Sai Yashwanth Injeti

Open Access Theses & Dissertations

The industrial demand for low density high strength steels without compromising on ductility in is endless. In this regards, grain refinement and austenitic stability considered to the practical approach in order to meet the needs. The concept of phase reversion involving sever cold deformation of metastable austenite to generate strain-induced martensite, followed by time-temperature annealing sequence, was used to obtain varying grain size from nanograined/ultrafine-grained (NG/UFG) to coarse-grained (CG) regime. This concept was used to obtain "high strength-high ductility" combination in nano/ultrafine-grained (NG/UFG) austenite stainless steel. Using this concept, the objective of the study here is to elucidate the dependence …


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 Jan 2019

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. …


Tailoring The Mechanical And Optical Properties Of Silicon-Niobium-Nitride Composite Coatings, Cristian Orozco Jan 2019

Tailoring The Mechanical And Optical Properties Of Silicon-Niobium-Nitride Composite Coatings, Cristian Orozco

Open Access Theses & Dissertations

Nitride nanocomposite thin films have generated significant attention as a result of their robust mechanical properties, excellent triobology, and good chemical (corrosion) stability. Due to their excellent hardness and high wear resistance NbN coatings have found use in a wide variety of applications such as the coating of cutting tools and to strengthen the surface mechanical properties of superconducting cavities. The mechanical properties of NbN can be further improved through mixing with Si3N4, leading to the formation of a nanocomposite structure. NbN-Si3N4 nanocomposite coatings have been actively studied due to their high hardness, high elastic modulus, and high resistance to …


Towards Multiple Model Approach To Bridge Deterioration, Jin A. Collins Jan 2019

Towards Multiple Model Approach To Bridge Deterioration, Jin A. Collins

Open Access Theses & Dissertations

The Intermodal Surface Transportation Efficiency Act of 1991 (ISTEA) marked the start of a new era in transportation in the United States. ISTEA required transportation agencies to take a proactive approach to planning and management of their assets. This included requirements for managing pavement, bridges, safety, congestion, public transportation, and intermodal systems. For horizontal transportation assets (i.e., bridges and pavement), deterioration modeling is an essential tool (Yanev and Chen 1993). Since ISTEA, Bridge Management Systems (BMS) have been utilized to inform decision-making regarding bridge projects such as maintenance, rehabilitation, and replacement (MR&R) under financial limitations (Agrawal, Kawaguchi, and Chen 2010). …


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 Jan 2019

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 …


Varying Ratios Of Collagen I And Iii For The Study Of Fibrotic Conditions In Tissue Engineering, Brian Roman Jan 2019

Varying Ratios Of Collagen I And Iii For The Study Of Fibrotic Conditions In Tissue Engineering, Brian Roman

Open Access Theses & Dissertations

Maintenance of collagen I (Col I) and III (Col III) in a 3:1 ratio is necessary to promote cardiac health. Increase in the relative amount of Col I within the myocardium, leads to an imbalance of Col I:III during cardiac fibrosis, which has damaging effects on cardiomyocytes (CM). To represent fibrous- and normal-cardiac tissue, gels composed of Col I:III ratios of 9:1 and 3:1 were developed and used to study resultant changes in CM function. Second harmonic generation (SHG) microscopy, used to image Col I fibers, displayed a decrease in image intensity with the addition of the non-second harmonic Col …


Thermal Characterization Of Abs/Carbon Fiber, Abs/ Glass Fiber And Petg/Glass Fiber Reinforced Composites Used In Large Area Additive Manufacturing, Fernando Adrian Rodriguez Lorenzana Jan 2019

Thermal Characterization Of Abs/Carbon Fiber, Abs/ Glass Fiber And Petg/Glass Fiber Reinforced Composites Used In Large Area Additive Manufacturing, Fernando Adrian Rodriguez Lorenzana

Open Access Theses & Dissertations

Additive manufacturing has seen continuous advancements, such as the inclusion of large-area additive manufacturing extrusion systems. These systems precede small-scale 3D printing by means of research and technological development for the manufacturing of plastic and fiber industries. Big Area Additive Manufacturing (BAAM), a material extrusion process, is capable of 3D printing large parts using thermoplastic composites by adding fiber reinforcements. The incorporation of fibrous materials, carbon fiber (CF) or glass fiber (GF), is a common practice in which percentage nominal ratios of fiber reinforcement by weight are implemented to the polymer matrix. In general, this enables warpage reduction during printing, …


In Situ Selective Nitriding Using An Open Source Laser Powder Bed Fusion System, Andres Gerardo Navarro Jan 2019

In Situ Selective Nitriding Using An Open Source Laser Powder Bed Fusion System, Andres Gerardo Navarro

Open Access Theses & Dissertations

Conventional forms of nitriding titanium limit the locations to surfaces, limiting applications to simple coatings. Additive manufacturing methods provide the opportunity for surface coating methods to be utilized in a layer by layer fabrication method and increase the uses of nitrides. Laser powder bed fusion (LPBF) in particular, provides a fabrication environment with sufficient energy to allow for material nitriding as well as the flexibility of being able to utilize a variety of materials and shielding gases for processing. This project utilizes an AconityONE open source LPBF system with custom laser parameter settings to fabricate and nitride Ti-6Al-4V substrates. This …


Adaptive Microphone Array Systems With Neural Network Applications, Jazmine Marisol Covarrubias Jan 2019

Adaptive Microphone Array Systems With Neural Network Applications, Jazmine Marisol Covarrubias

Open Access Theses & Dissertations

A microphone array integrated with a neural network framework is proposed to enhance and optimize speech signals derived from environments prone to noise and room reflections that cause reverberation. Microphone arrays provide a way to capture spatial acoustic information for extracting voice input from ambient noise. In this study, we utilize and analyze established signal processing methods combined with different neural network architectures to achieve denoised and dereverberated speech signal results that are comparable with their clean, anechoic versions. The first stage of the proposed system involves using datasets containing anechoic speech recordings of speech utterances and convolving them with …


Quantifying Early-Age Concrete Mechanical Properties And Curing Conditions Utilizing An Automated System, Benjamin Arras Jan 2019

Quantifying Early-Age Concrete Mechanical Properties And Curing Conditions Utilizing An Automated System, Benjamin Arras

Open Access Theses & Dissertations

The validation of concrete quality based on the 28-day strength is a lengthy process. Predicting concrete mechanical properties through early-age methods can streamline the construction process. Early-age concrete behavior consists of assessing the concrete curing as-related to setting stages, the hydration process, strength and stiffness development, while considering various environmental system parameters. This paper reports on a nondestructive method for observing the early-age strength and modulus development of concrete mixes over seven days in a controlled, laboratory setting. An apparatus was designed and built for continuous acquisition of seismic modulus data (using free-free resonant column) and heat of hydration/maturity information …


Energy Management And Control Of Smart Power Distribution Systems, Eric Galvan Jan 2019

Energy Management And Control Of Smart Power Distribution Systems, Eric Galvan

Open Access Theses & Dissertations

With the development of distributed energy resources (DERs) and advancements in technology, microgrids (MGs) appear primed to become an even more integral part of the future distribution grid. In this transition to the smart power grid of the future, MGs must be properly managed and controlled to allow efficient integration of DERs. Over the past years, there has been rapid adoption of roof-top solar photovoltaic (PV) and battery electric vehicles (BEVs). Although roof-top solar PV and BEVs can provide environmental benefits (e.g., reduction of emissions), they also create various challenges for power system operators. For example, roof-top solar PV generation …


Platelet Biology And Thrombosis: Juul E-Cigarette Exposure And 5ht2a Receptor Drug Discovery, Jean Emmanuel Montes Ramirez Jan 2019

Platelet Biology And Thrombosis: Juul E-Cigarette Exposure And 5ht2a Receptor Drug Discovery, Jean Emmanuel Montes Ramirez

Open Access Theses & Dissertations

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Structures And Daq System For The Lox/Lch4 500 And 2000 Lbf. Rocket Engines, Rachel Pilgrim Jan 2019

Structures And Daq System For The Lox/Lch4 500 And 2000 Lbf. Rocket Engines, Rachel Pilgrim

Open Access Theses & Dissertations

With the progression of space exploration and research, new alternative fuels and fuel combinations have been discovered. The ability to produce methane from Mars' atmosphere and oxygen from Mars' regolith has led to the two becoming a great alternative propellant combination for rocket propulsion systems. To further advance LOX/LCH4 propulsion systems, a 500 and 2000 lbf rocket engine were designed and manufactured and are to be launched from the MIRO cSETR Technology Research and Innovation Acceleration Park (tRIAc) in Fabens, Texas for data collection and analysis. The objective of this thesis is to give a thorough overview of the static …


Image Analysis For Lung Cancer Diagnosis And Superresolution Localization Microscopy, Xia Huang Jan 2019

Image Analysis For Lung Cancer Diagnosis And Superresolution Localization Microscopy, Xia Huang

Open Access Theses & Dissertations

With the development of imaging analysis techniques, flurry of applications associated with it has been hatched. In this paper, image analysis on both organ and cellular levels will be demonstrated. For organ level images, a deep learning based computer aided lung cancer diagnosis based on computer tomography images is studied. Deep learning techniques have been extensively used in computerized pulmonary nodule analysis recent years. Many reported studies still utilized hybrid methods for diagnosis, in which convolutional neural networks (CNNs) are used only as one part of the pipeline, and the whole system still needs either traditional image processing modules or …


Decision Support Tools For Parking Management On University Campuses, Okan Gurbuz Jan 2019

Decision Support Tools For Parking Management On University Campuses, Okan Gurbuz

Open Access Theses & Dissertations

University campuses generate and attract trips with unique characteristics. Most universities are constantly challenged by the parking congestion issues. To manage campus parking infrastructure, most universities have established parking departments. This department is referred as the University Parking Office (UPO) in this Dissertation. There is no methodology or tool to assist the UPOs in their decision-making process. This Dissertation focuses on student parking and has developed models and methodologies as decision support tools to assist UPOs in managing student parking on campuses.

This Dissertation answers six Research Questions related to parking management on university campuses: (1) How many students are …


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 Jan 2019

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 …


System Dynamic Model Of 1-Dimensional Unsaturated Water And Solute Transport For Predicting Salinity Stress In Crops, Thomas Poulose Jan 2019

System Dynamic Model Of 1-Dimensional Unsaturated Water And Solute Transport For Predicting Salinity Stress In Crops, Thomas Poulose

Open Access Theses & Dissertations

There is a complex non-linear system dynamic between the water and salt transport in the unsaturated vadose zone where the salt transport and accumulation affect the water fluxes and vice versa. In addition, factors such as precipitation, transpiration, water infiltration and solute transport in the unsaturated zone of subsurface soil further complicate the processes involved. We have developed a system dynamics model for simulating the one-dimensional unsaturated water and solute transport along with root water uptake in the vadose zone. The model uses finite difference method for solving Richard's equation with a sink term for water transport and root water …


Tailoring Physical Properties Of Shape Memory Polymers For Fdm-Type Additive Manufacturing, Paulina Aileen Quinonez Jan 2019

Tailoring Physical Properties Of Shape Memory Polymers For Fdm-Type Additive Manufacturing, Paulina Aileen Quinonez

Open Access Theses & Dissertations

Shape memory polymers (SMPs) have found applicability in biomedical settings as well as other uses that can take advantage of objects that can change shape upon exposure to stimulus. Integrating polymers with shape memory characteristics into additive manufacturing technologies such as fused deposition modeling (FDMâ?¢) can increase the number of applications this manufacturing platform can be utilized. Currently, polyurethane and polylactic acid (PLA) are two FDMâ?¢-compatible materials that possess shape memory properties. On their own these materials do not have tunable shape memory properties, namely shape recovery and shape fixation. The work presented here entails the development and characterization of …


Thermal/Mechanical Analysis And Development Of A 2000 Lbf Liquid Oxygen/Liquid Methane Rocket Engine, Marissa Garcia Jan 2019

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 …


Artificial Intelligence In The Assessment Of Transmission And Distribution Systems Under Natural Disasters Using Machine Learning And Deep Learning Techniques In A Knowledge Discovery Framework, Rossana Villegas Jan 2019

Artificial Intelligence In The Assessment Of Transmission And Distribution Systems Under Natural Disasters Using Machine Learning And Deep Learning Techniques In A Knowledge Discovery Framework, Rossana Villegas

Open Access Theses & Dissertations

Warming trends and increasing temperatures have been observed and reported by federal agencies, such as the National Oceanic and Atmospheric Administration (NOAA). Extreme-weather events, especially hurricanes, tornadoes and winter storms, are among the highly devastating natural disasters responsible for massive and prolonged power outages in Electrical Transmission and Distribution Systems (ETDS). Moreover, the failure rate probability of any system component under extreme-weather tends to increase in the impacted geographic area. This Dissertation proposes an Artificial Intelligence (AI) Decision Support System that can predict damage in the ETDS and allow operators to mitigate disastrous extreme weather events. The document reports the …


Cfd Dem Analysis Of A Dry Powder Inhaler, Antara Badhan Jan 2019

Cfd Dem Analysis Of A Dry Powder Inhaler, Antara Badhan

Open Access Theses & Dissertations

Dry powder inhalers (DPIs), used as a means for pulmonary drug delivery, typically contains a combination of an Active Pharmaceutical Ingredient (API) and significantly larger carrier particles. The micro-sized drug particles - which have a strong propensity to aggregate and a poor aerosolization performance - are mixed with significantly large carrier particles that are unable to penetrate the mouth-throat region to deagglomerate and entrain the smaller API particles in the inhaled airflow. The performance of a DPI, therefore, depends on entrainment the carrier-API combination particles and the time and thoroughness of the deagglomeration of the individual API particles from the …


Additive Manufactured Ear Pinna For Spatial Cue Preservation In Custom Hearing Devices, Carlos Felipe Acosta Carrasco Jan 2019

Additive Manufactured Ear Pinna For Spatial Cue Preservation In Custom Hearing Devices, Carlos Felipe Acosta Carrasco

Open Access Theses & Dissertations

Advancements in additive manufacturing/3D printing technologies has permitted the fabrication of intricate features such as the ones present in the human ear. The outer ear, also known as the pinna, allows for the spectral cues from incoming sound to be captured and identified. The hypothesis of the preservation of auditory localization and externalization relies on the fabrication of an ear pinna via additive manufacturing embedded into a headset for spectral cue preservation and hearing protection. Before exploring these custom circumaural hearing devices, a study on the fabrication process of AM pinnae was performed. The KEMAR system for acoustic research was …


Segmentation And Registration Based Automatic Cancer Proton Treatment Analysis, Yang Zhang Jan 2019

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 …


Direct Write 3d Printing Of Functional Ceramics, Jorge Angel Diaz Jan 2019

Direct Write 3d Printing Of Functional Ceramics, Jorge Angel Diaz

Open Access Theses & Dissertations

Humidity sensors are used in many industries and are important for ensuring quality and safety. Ceramic sensors are preferred because of their quick response time, ability to withstand high temperatures and excellent Chemical and mechanical stability. The manufacturing world has been moving toward additive manufacturing which is a form of synthesizing 3D tangible layer by layer in witch minimal waste is produced. Additive manufacturing also is known as 3D printing has opened new possibilities to design engineers by giving them design freedom and access to the layers of a part to allow embedded sensors. There is a category of ceramics …


Interference Mitigation Of Adjacent Radio Frequency Signals On A Flexible Software-Defined Radio Testbed Platform, Mirza Mohammad Maqbule Maqbule Elahi Jan 2019

Interference Mitigation Of Adjacent Radio Frequency Signals On A Flexible Software-Defined Radio Testbed Platform, Mirza Mohammad Maqbule Maqbule Elahi

Open Access Theses & Dissertations

The radio frequency (RF) spectrum is crowded with users and adjacent frequency users are facing an increase in interference from each other. The spectrum governing body Federal Communications Commission (FCC) has the difficult task of allocating spectral bands for new users for mobile devices using 4G LTE technology. Telemetry is affected by the adjacent band 4G LTE users in terms of signal degradation. To minimize the interference between adjacent frequency users, several methods can be used. A common but inefficient method separates adjacent band frequencies using guard bands which leaves a big portion of the spectrum unused. Alternatively, adjacent RF …


Small Satellite Development At Utep, Emily Herzog Jan 2019

Small Satellite Development At Utep, Emily Herzog

Open Access Theses & Dissertations

The small satellite industry has seen tremendous growth in recent years. A CubeSat is a particular type of standardized small satellite that follows the CubeSat specifications. These specifications define the structural, testing, and operational requirements of the satellite. This standard facilitates cheaper design, integration, and launch of satellites, allowing smaller organizations to participate in the normally costly area of space exploration.

The University of Texas at El Paso has recognized the opportunity and has begun developing several CubeSats. The two that are the topic of this Thesis are called Orbital Factory II (OFII) and Orbital Factory X (OFX). An on-orbit …