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Full-Text Articles in Engineering

Development Of An Automated Electronic Prototyping System, Cesar Yahir Sanchez Zambrano May 2022

Development Of An Automated Electronic Prototyping System, Cesar Yahir Sanchez Zambrano

Open Access Theses & Dissertations

Prototyping systems with interconnected components can be a time and resource expensive process. The process consists of three main phases (design, build and analysis) with each having their own associated cost. For the case of electronic circuits, the building phase is the costliest phase among the three, being prone to human errors which causes the circuit to fail. All three phases of the prototyping process are important. However, often a disproportionate amount of time is spent on the build phase due to the difficulty of making and troubleshooting circuits by hand. In this thesis we will discuss a system that …


Equity Driven Data Analysis For Public Transportation Planning, Gerardo Ivan Valenzuela Mendoza May 2022

Equity Driven Data Analysis For Public Transportation Planning, Gerardo Ivan Valenzuela Mendoza

Open Access Theses & Dissertations

Existing public transportation planning methods use a trip-based approach rather than a user-based approach; a user-based approach is sensitive to a broader range of planning strategies and policies, especially those that affect or take into consideration how users spend their time and resources. Even though transportation planning agencies such as Metropolitan Planning Organizations (MPOs) are required to strive for environmental and social justice, there is still a gap that needs to be filled. Urban population growth and urbanization with its impact on public planning require continuous research to address the constantly evolving challenges when it comes to transportation. As cities …


All-In-One Multi3d System: Exploring Potential Of 5-Axis Material Extrusion Additive Manufacturing, Angel Vega May 2022

All-In-One Multi3d System: Exploring Potential Of 5-Axis Material Extrusion Additive Manufacturing, Angel Vega

Open Access Theses & Dissertations

Additive Manufacturing (AM) has experienced consistent growth since its inception across its seven process categories, especially Material Extrusion (MEX) with systems that can be seen in commercial and industrial settings. As MEX evolves, innovation can be traced in the growing variety of available process materials and new system capabilities leading to greater interest in the technology across various industries including automotive, aerospace and even nuclear weapons. This has created an increasing demand for end-use parts from MEX systems leading to more complex machines with additional Degrees of Freedom (DoF), specialized workflows, and expanded post processing that address the drawbacks of …


3d Printing Of Ceramics And Polymers For Engineering Applications, Jesus Javier Mata May 2022

3d Printing Of Ceramics And Polymers For Engineering Applications, Jesus Javier Mata

Open Access Theses & Dissertations

The Additive Manufacturing industry, in the last years [1] has shown a great push with the development and inclusion of new technologies that have enable the engineering world to achieve great advances. As a consequence of this surge of new technology deriving from the basic principle that conforms additive manufacturing, according to the ASTM a total of seven categories have been defined. The inclusion of these new technologies and the ongoing advances in material implementation has provided the industry with a degree of freedom never seen before, leading to the creation of new solutions to existing problems that seemed impossible …


The Mobility And Cognitive Mechanisms Involved In Altering Gait Speed In Children With Autism Spectrum Disorder, Alyssa Olivas May 2022

The Mobility And Cognitive Mechanisms Involved In Altering Gait Speed In Children With Autism Spectrum Disorder, Alyssa Olivas

Open Access Theses & Dissertations

Autism is a socio-behavioral disorder, and diagnoses are conducted through behavioral screening instruments. Recent research suggests motor deficits may be a core symptom of the disorder, as children with autism present with deficits in motor development, locomotor skills, and postural instability. In addition, children with autism often have affected, executive function, attention, and perception cognitive domains. Different gait speeds have been used to examine gait adaptations in other clinical populations. Additionally, individuals with decreased cognitive abilities have demonstrated difficulties in modulating their walking speed. There is limited research on mechanisms children with autism use to alter their gait speed, or …


Practical Applications Of Pressure-Fed Lox/Ch4 Rocket Engines, James Susen Parks May 2022

Practical Applications Of Pressure-Fed Lox/Ch4 Rocket Engines, James Susen Parks

Open Access Theses & Dissertations

The University of Texas at El Paso Aerospace Center is working on a family of LOX/CH4 pressure-fed rocket engines. The applications of a pressure-fed rocket engine include orbital launch vehicles and lunar ascent and descent vehicles. This dissertation focuses on the application of the CROME LOX/CH4 engines under development at UTEP. The dissertation contains three chapters on orbital launch vehicles and a fourth chapter on lunar descent/ascent vehicles. The first two chapters look at pressure-fed LOX/CH4 orbital launch vehicle design compared to an electric pump fed and a gas generator vehicle. The third chapter looks at the sensitivities in the …


Lithospheric Structure Underneath The Archean Tanzania Craton And Adjacent Regions From A Joint Inversion Of Receiver Functions And Rayleigh-Wave Phase Velocity Dispersion, Tuo Wang, Stephen S. Gao, Qiuyue Yang, Ling Chen, Kelly H. Liu May 2022

Lithospheric Structure Underneath The Archean Tanzania Craton And Adjacent Regions From A Joint Inversion Of Receiver Functions And Rayleigh-Wave Phase Velocity Dispersion, Tuo Wang, Stephen S. Gao, Qiuyue Yang, Ling Chen, Kelly H. Liu

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

Lithospheric structure beneath the Archean Tanzania craton and adjacent regions, including segments of the East African rift system (EARS) and the Proterozoic-early Paleozoic orogenic belts between the EARS and the craton, is imaged by a joint inversion of receiver functions and Rayleigh wave dispersion measurements derived from ambient seismic noise for shorter periods and teleseismic data for longer periods. Our resulting crustal thickness, crustal VP= VS measurements and 3D shear-wave velocity model for the upper 120 km show a clear spatial correspondence with major surficial geological features. The new results suggest the presence of a mafic layer in the bottom …


Paso Robles Police Department Shooting Range Shade Structure, Evan Marshall Cogswell May 2022

Paso Robles Police Department Shooting Range Shade Structure, Evan Marshall Cogswell

Construction Management

The Paso Robles Police Department has been a partner for multiple senior projects working to develop improvements for their shooting range. The shooting range is used extensively by officers year-round, with the climate being hot in the summer and rainy in the winter. We wanted to provide a shade structure located between the two shipping containers used for storage so that the officers would have a sheltered place to provide instruction, clean their weapons, and rest in between rounds on the range. This type of project was new to all three of us in the group – Parker Smith, Kevin …


Mechanical Properties Of Fusion Welded Ceramics In The Sic-Zrb2 And Sic-Zrb2-Zrc Systems, Jecee D. Jarman, William Fahrenholtz, Greg Hilmas, Jeremy Lee Watts, Derek S. King May 2022

Mechanical Properties Of Fusion Welded Ceramics In The Sic-Zrb2 And Sic-Zrb2-Zrc Systems, Jecee D. Jarman, William Fahrenholtz, Greg Hilmas, Jeremy Lee Watts, Derek S. King

Materials Science and Engineering Faculty Research & Creative Works

Mechanical properties of welded SiC-ZrB2 and SiC-ZrB2-ZrC ceramics were measured up to 1700 °C. Commercial powders were hot pressed, machined into coupons, and preheated to 1600 °C before joining the ceramics using either tungsten inert gas welding or plasma arc welding. Toughness of the parent materials was 3–4 MPa*m1/2 which decreased after welding to 2–2.5 MPa*m1/2. Strength of the SiC-ZrB2-ZrC parent material was ~700 MPa at 25 °C, ~300 MPa at 1700 °C, and retained 40–60% of this strength once welded. Strength of the SiC-ZrB2 parent material was ~600 MPa at 25 °C and 1700 °C and retained 20–30% of …


Pressureless Sintering Of Zirconium Diboride With Carbon And Boron Carbide Nanopowder, Eric W. Neuman, Gregory E. Hilmas, William Fahrenholtz May 2022

Pressureless Sintering Of Zirconium Diboride With Carbon And Boron Carbide Nanopowder, Eric W. Neuman, Gregory E. Hilmas, William Fahrenholtz

Materials Science and Engineering Faculty Research & Creative Works

Zirconium diboride ceramics with and without carbon and boron carbide nano powder additives were prepared by ball milling with ZrB2 grinding media and pressureless sintering. Additions of up to 1 wt% nano-B4C and 0.5 wt% C were made to the ZrB2 powder. The materials were then sintered between 1800 and 2300 °C for between 90 and 360 min in an Ar/10H2 atmosphere. After sintering at 2200 °C for 90 min, densities ranged from 88.3 to 90.7% for the ZrB2 with 0–1.0% nano-B4C addition. Carbon additions of 0.5 wt% and nano-B4C additions from 0 to 1.0 wt% resulted in densities ranging …


Electrochromic Windows: Return On Investment Analysis, Thomas Michael Caprio May 2022

Electrochromic Windows: Return On Investment Analysis, Thomas Michael Caprio

Construction Management

In recent years, sustainability in construction has become a topic of undeniable interest. With sustainability certifications becoming more prominent and desirable, members of the construction industry have begun to seek alternatives for standard systems to keep up with market trends. One of the main issues that the construction industry faces is accessibility of technology. While there are new products and technologies being released frequently, members of the construction industry lack knowledge on the specific details and implications of working with newer systems. One piece of technology that was recently introduced is electrochromic glass, or smart glass. Electrochromic windows analyze sunlight …


Precast Concrete Manufacturing Business Plan, John F. Will Jr. May 2022

Precast Concrete Manufacturing Business Plan, John F. Will Jr.

Construction Management

The Central Coast of California has been under development since the Great Recession of 2008. Throughout this development, there has been an exceedingly high demand for precast concrete products, specifically in the civil sector of the construction industry. These products are being utilized by more and more by contractors around the world. This demand has emerged from the lack of concrete product manufacturers in this region of California. This project introduces a business plan for a new precast concrete product manufacturer by the name of J.W. Concrete Products LLC. The objective of this business plan is to reflect the benefits …


Installation Of Electrical System For Paso Robles Police Department, Jacob M. Studebaker, Peter D. Strykers May 2022

Installation Of Electrical System For Paso Robles Police Department, Jacob M. Studebaker, Peter D. Strykers

Construction Management

This paper outlines the process that Peter Strykers and Jacob Studebaker went through to set up the lighting and power system for the Paso Robles Police Department gun range located off highway 46. Before our installation, the gun range had zero lighting so the officers could not use it after sunset. We allowed the officers to light the gun range with outdoor LED lights, light up both the storage units on site, and have access to multiple outlets inside and out of the storage units. The power source that the electrical system runs on comes from a Kubota generator because …


Development Of High Conductivity Copper Coatings For Srf Cavity, Himal Pokhrel May 2022

Development Of High Conductivity Copper Coatings For Srf Cavity, Himal Pokhrel

Physics Theses & Dissertations

The development of metallic coatings with high purity and high thermal conductivity at cryogenic temperature could be very important for application to the superconducting radiofrequency (SRF) cavity technology. The deposition of such bulk coatings on the outer surface of a niobium cavity could result in higher heat conductance and mechanical stiffness, both of which are crucial for enhancing the cavity performance at a reduced cost.

Cold spray technology was used to deposit bulk coatings of pure copper and copper-tungsten alloys on the niobium substrate and the samples of size 2 mm × 2 mm cross section were cut and subjected …


Investigating Arrhythmia Potential In Cardiac Myocytes In Presence Of Long Qt Syndrome, Victoria Lin Lam May 2022

Investigating Arrhythmia Potential In Cardiac Myocytes In Presence Of Long Qt Syndrome, Victoria Lin Lam

Biomedical Engineering Theses & Dissertations

Long QT Syndrome (LQTS) is an increasingly studied condition that leads to potentially fatal heart rhythm disorders, called arrhythmias, and sudden cardiac death. The alterations in the electrocardiograms (ECGs) seen in LQTS patients is caused by mutations to genes related to ion channels in cardiac cells. Computational modeling allows the mechanistic study of these ion channel mutations in LQTS by providing quantitative predictors of cardiac behavior in human and rabbit heart models. This work hypothesizes that the repolarization reserve in cardiac Purkinje cells (PC), that form the cardiac conduction system, is lower than that of ventricular myocytes (VM), resulting in …


Training The Responsible Conduct Of Research And Design, Jay R. Goldberg May 2022

Training The Responsible Conduct Of Research And Design, Jay R. Goldberg

Biomedical Engineering Faculty Research and Publications

Students Supported by grants from the National Institutes of Health (NIH) are required to complete training in the responsible conduct of research (RCR). This training includes topics such as authorship, handling of data, reporting of results, maintaining confidentiality, and other topics related to the ethical and responsible conduct of research. It prepares students who are supported by NIH research grants for careers involving research.


Installation Of Electrical System For Paso Robles Police Department, Peter D. Strykers, Jacob M. Studebaker May 2022

Installation Of Electrical System For Paso Robles Police Department, Peter D. Strykers, Jacob M. Studebaker

Construction Management

This paper outlines the process that Peter Strykers and Jacob Studebaker went through to set up the lighting and power system for the Paso Robles Police Department gun range located off highway 46. Before our installation, the gun range had zero lighting so the officers could not use it after sunset. We allowed the officers to light the gun range with outdoor LED lights, light up both the storage units on site, and have access to multiple outlets inside and out of the storage units. The power source that the electrical system runs on comes from a Kubota generator because …


Intelligibility Of Medically Related Sentences In Quiet, Speech-Shaped Noise, And Hospital Noise, Tessa Bent, Melissa Baese-Berk, Erica E. Ryherd, Sidney Perry May 2022

Intelligibility Of Medically Related Sentences In Quiet, Speech-Shaped Noise, And Hospital Noise, Tessa Bent, Melissa Baese-Berk, Erica E. Ryherd, Sidney Perry

Durham School of Architectural Engineering and Construction: Faculty Publications

Noise in healthcare settings, such as hospitals, often exceeds levels recommended by health organizations. Although researchers and medical professionals have raised concerns about the effect of these noise levels on spoken communication, objective measures of behavioral intelligibility in hospital noise are lacking. Further, no studies of intelligibility in hospital noise used medically relevant terminology, which may differentially impact intelligibility compared to standard terminology in speech perception research and is essential for ensuring ecological validity. Here, intelligibility was measured using online testing for 69 young adult listeners in three listening conditions (i.e., quiet, speech-shaped noise, and hospital noise: 23 listeners per …


Fabrication And Characterization Of Lactobacillus Crispatus Containing Bioprints For Bacterial Vaginosis Application., Anthony J. Kyser May 2022

Fabrication And Characterization Of Lactobacillus Crispatus Containing Bioprints For Bacterial Vaginosis Application., Anthony J. Kyser

Electronic Theses and Dissertations

Bacterial vaginosis (BV) is a condition in which healthy lactobacilli are replaced by an overabundance of pathogenic bacteria in the female reproductive tract. Current antibiotic treatments often fail to “cure” infection, resulting in recurrence in more than 50% of women, 6 months post-treatment. Recently, probiotics have demonstrated promise to restore vaginal health; however, as with other active agents, delivery requires once-to-twice daily administration. Recently, three-dimensional (3D)-bioprinting has enabled the fabrication of well-defined cell-laden architectures with tunable agent release, thereby presenting a novel approach with which to deliver probiotics. One promising bioink, gelatin alginate, was selected for study, due to its …


Release Kinetics Of Metronidazole From 3d Printed Silicone Scaffolds., Sydney E. Herold May 2022

Release Kinetics Of Metronidazole From 3d Printed Silicone Scaffolds., Sydney E. Herold

Electronic Theses and Dissertations

Sustained local administration of active agents has been proposed to cure bacterial vaginosis in the female reproductive tract and restore the resident bacterial fauna. Bioprinting has shown promise for the development of systems for local agent delivery. In contrast to oral ingestion, agent release kinetics can be fine-tuned by bioprinting specialized scaffold designs tailored for particular treatments while enhancing dosage effectiveness via localized sustained release. It has been challenging to establish scaffold properties for sustained release as a function of fabrication parameters. Towards this goal, we evaluate 3D printed scaffold formulation and feasibility to sustain release of metronidazole, a representative …


Effects Of Sizing Agents On Mechanical Properties Of Carbon Fiber–Polymer Composites Via Fused Filament Fabrication Additive Manufacturing., Benjamin D. Mitchell May 2022

Effects Of Sizing Agents On Mechanical Properties Of Carbon Fiber–Polymer Composites Via Fused Filament Fabrication Additive Manufacturing., Benjamin D. Mitchell

Electronic Theses and Dissertations

This study demonstrated the effects of changing the sizing agent parameter during the preparation of carbon fibers on the mechanical properties of composite made with acrylonitrile butadiene styrene (ABS) as the matrix material and carbon fibers as the fiber material. Three types of sizing agents produced by Allnex were used to coat three different batches of carbon fibers that were mixed with a torque rheometer and extruded with a barrel-style melt extruder into continuous spools of 1.75 mm filament for use with commercial 3D printers. Tensile tests were conducted on the filaments and tensile bars printed from the materials. Results …


Machine Learning Analysis Of Acoustic Attenuation Measurements For Cellular Characterization., John T. Moore May 2022

Machine Learning Analysis Of Acoustic Attenuation Measurements For Cellular Characterization., John T. Moore

Electronic Theses and Dissertations

T-cell therapies have been gaining popularity in recent years due to their cancer fighting potential. With remission rates improving in this field of immunotherapy, the demand for T-cell therapies has also increased; however, the cell processing techniques for these therapeutic products have yet to rise to the level of demand. The manufacturing process takes too long and a significant amount of processed cell batches can fail to meet safety requirements. These limitations of cell processing can be detrimental to patients seeking T-cell therapies. While current products have improved the time it takes to manufacture these therapeutic products, there is still …


Acoustofluidic Delivery Of Gene Editing Compounds For Improved Immunotherapy Processing., Riyakumari K. Patel May 2022

Acoustofluidic Delivery Of Gene Editing Compounds For Improved Immunotherapy Processing., Riyakumari K. Patel

Electronic Theses and Dissertations

Cell-based immunotherapies are a new generation of “living-drug” treatments for cancer and other diseases. Chimeric antigen receptor (CAR) T-cell cancer therapy has shown promising results in lymphoma and B-cell malignancies. Currently, there are six FDA-approved CAR-T drugs on the market, and all of them use viral transfection for reprogramming. While viral transfection is effective, there are safety concerns due to inconsistent transfection that limit the use of CAR-T therapy. Current non-viral transfection techniques generally have lower transfection efficiency than viral transfection. Additionally, these techniques can be toxic, time-consuming, non-transportable, and expensive. To address these limitations, a novel 3D printed acoustofluidic …


Regression Tree Predictive Filter, Jarren Worthen May 2022

Regression Tree Predictive Filter, Jarren Worthen

Undergraduate Honors Capstone Projects

Many algorithms have been developed to predict future samples of a signal. These algorithms, such as the recursive least squares predictive filter, rely on the assumption that the system generating the signal can be modeled as a linear system of equations. These systems perform poorly when used to predict signals generated by non-linear systems. To predict a non-linear signal, non-linear methods must be used. Regression trees are a simple form of machine learning that is non-linear in nature and can predict output based on a set of given input. The goal of this capstone project was to develop an algorithm …


Ng-Torque/Tension Testing Of Bolts With Epoxy Primer, Gabrielle Van Brunt May 2022

Ng-Torque/Tension Testing Of Bolts With Epoxy Primer, Gabrielle Van Brunt

Undergraduate Honors Capstone Projects

This capstone project is in conjunction with Northrop Grumman (NG). The goal of the project is for NG to apply an epoxy in the future to aerospace structures that they produce. This epoxy is meant to prevent corrosion of threaded joints in the structures. Although NG has the epoxy and has no issues procuring it, NG does not know the properties of the epoxy; it cannot be used until the epoxy’s nut factor is experimentally determined. The epoxy nut factor will be used for design and drawing purposes on various projects. To determine the nut factor, the Aggiepoxy team created …


Material Synthesis And Machine Learning For Additive Manufacturing, Jaime Eduardo Regis May 2022

Material Synthesis And Machine Learning For Additive Manufacturing, Jaime Eduardo Regis

Open Access Theses & Dissertations

The goal of this research was to address three key challenges in additive manufacturing (AM), the need for feedstock material, minimal end-use fabrication from lack of functionality in commercially available materials, and the need for qualification and property prediction in printed structures. The near ultraviolet-light assisted green reduction of graphene oxide through L-ascorbic acid was studied with to address the issue of low part strength in additively manufactured parts by providing a functional filler that can strengthen the polymer matrix. The synthesis of self-healing epoxy vitrimers was done to adapt high strength materials with recyclable properties for compatibility with AM …


Enhancement Of Fabrication Procedures By Modularization, Andres Sagredo May 2022

Enhancement Of Fabrication Procedures By Modularization, Andres Sagredo

Open Access Theses & Dissertations

Fabrication of semiconductor technology grows in importance every year, from metal-oxide-semiconductor (MOS) technology to fabricating integrated circuits (ICs) used in everyday life. These ICs are implemented into computers, phones, and vehicles for complex functions and safety features. Another semiconductor technology is microelectromechanical systems (MEMS), located in actuators and sensors on multiple systems. In academia, it is inherently essential for students to learn the theory of such devices and have exposure to the fabrication process of the technology in question. The importance of theory and practice in fabrication is skyrocketing due to the global chip shortage, making workforce development vital for …


Calcium Ferrite As A Semiconductor For Microbially Assisted Photocatalytic Reduction Of Carbon Dioxide, Lauren King May 2022

Calcium Ferrite As A Semiconductor For Microbially Assisted Photocatalytic Reduction Of Carbon Dioxide, Lauren King

Honors Scholar Theses

The pressing issue of global climate change has been found to be attributed to the increasing concentration of greenhouse gases in the atmosphere, especially carbon dioxide. One mitigation idea to close the carbon loop is to utilize redox reactions and photocatalysis to reduce carbon dioxide to a useable fuel source, like methane or methanol. This thesis will study the possibility of using calcium ferrite as the semiconductor to perform photocatalytic reduction of carbon dioxide with the assistance of a microbial fuel cell, which will help minimize the energy required from sunlight photons. A calcium ferrite thin film was produced through …


Triggering Thermal Runaway In Lithium-Ion Batteries, Chris John May 2022

Triggering Thermal Runaway In Lithium-Ion Batteries, Chris John

Honors Scholar Theses

The proliferation of lithium-ion batteries enables electric devices such as cell phones to electric vehicles to become a reality. A latent danger, however, exists in these batteries. Mechanical, thermal, or electrical damage can initiate a phenomenon known as thermal runaway (TR). This damage causes internal short circuits within the battery, releasing heat and triggering exothermic decomposition reactions. The battery will catch fire if rapid cooling is not present. While experimental designs exist for evaluating TR, significant safety hazards and impracticality may impede testing efforts. Finite element analysis, therefore, becomes a vital tool in modeling TR and mitigation techniques. However, there …


Study Of Porosity Of Gelatin-Alginate Hydrogels To Model Brain Matter For Studying Traumatic Brain Injuries, Apolline Vincent May 2022

Study Of Porosity Of Gelatin-Alginate Hydrogels To Model Brain Matter For Studying Traumatic Brain Injuries, Apolline Vincent

Honors Scholar Theses

Traumatic brain injuries (TBIs) affect brain tissue and neuronal signaling, leading to many side effects including death. Research on TBIs is limited by the lack of accurate brain matter models to study the physiological and cellular reaction. Alginate-gelatin hydrogels have been designed and modified to mimic the mechanical properties of the brain to act as an accurate in vitro model. This Honors thesis aims to verify the porous microstructure of gelatin-alginate hydrogels through Scanning Electron Microscopy (SEM) to understand how gelatin and alginate affect the microstructure. I measured the pore sizes of each hydrogel using ImageJ, compared the average pore …