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Articles 61 - 90 of 1943
Full-Text Articles in Engineering
Interoperability In An Electrified Pavement System: A Model-Based Systems Engineering Perspective, Beatriz Irene Soto
Interoperability In An Electrified Pavement System: A Model-Based Systems Engineering Perspective, Beatriz Irene Soto
Open Access Theses & Dissertations
In a 2021 statement provided by The White House, (The White House, 2021), the Biden administration announce the goal for electric vehicles to account for 50% of new vehicle sales in the United States by 2035. In addition, the legislation allocates a budget of $7.5 billion to build out a national network of EV chargers along highway corridors to facilitate long-distance travel and within communities to provide convenient charging where people live, work, and shop. This investment will support the President's goal of building a nationwide network of 500,000 EV chargers to accelerate the adoption of EVs, reduce emissions, improve …
Influence Evaluation On Near-Road Concentrations Of Pm2.5 During Covid-19 Pandemic, Marcos Alan Banda Morales
Influence Evaluation On Near-Road Concentrations Of Pm2.5 During Covid-19 Pandemic, Marcos Alan Banda Morales
Open Access Theses & Dissertations
SARS-CoV-2, also known as COVID-19, was discovered in Wuhan, China in late 2019and spread rapidly worldwide in 2020. The COVID-19 pandemic and its quarantine periods influenced the number of people using their vehicles and the number of miles traveled, which correspondingly influenced the air quality of urban areas. The influence of the restrictions caused by the quarantine period on air quality differs from location to location. Previous research accounted for countries, but no research was done at the state level individually. This research attempts to evaluate the transportation-related air quality during the COVID-19 pandemic period using data from the Texas …
Optimized Learning Using Fuzzy-Inference-Assisted Algorithms For Deep Learning, Miroslava Barua
Optimized Learning Using Fuzzy-Inference-Assisted Algorithms For Deep Learning, Miroslava Barua
Open Access Theses & Dissertations
For years, researchers in Artificial Intelligence (AI) and Deep Learning (DL) observed that performance of a Deep Learning Network (DLN) could be improved by using larger and larger datasets coupled with complex network architectures. Although these strategies yield remarkable results, they have limits, dictated by data quantity and quality, rising costs by the increased computational power, or, more frequently, by long training times on networks that are very large. Training DLN requires laborious work involving multiple layers of densely connected neurons, updates to millions of network parameters, while potentially iterating thousands of times through millions of entries in a big …
Processes & Toolchain For Automation Of Hybrid Direct-Write 3d Printing, Gilbert Thomas Carranza
Processes & Toolchain For Automation Of Hybrid Direct-Write 3d Printing, Gilbert Thomas Carranza
Open Access Theses & Dissertations
Hybrid 3D printing has evolved from a means to rapidly prototype devices to a fully viable means of manufacturing final products. In particular, electronic and electromagnetic devices have been a focus of hybrid 3D printing multi material structures. However, while the hardware capabilities have been around for years, the software capabilities have only begun to catch up. A process and toolchain for hybrid 3D printing is critically needed.This work details a process and toolchain for hybrid 3D printing metal dielectric structures. In it, a basic slicing algorithm is shown along with off-axis printing and conformal printing for arbitrary curvatures. These …
Engineering 3d Bioprinted Cardiac Spheroidal Droplets With Cardiomyocytes And Cardiac Fibroblasts For Tissue Engineering And Drug Cytotoxicity Studies, Raven El Khoury
Engineering 3d Bioprinted Cardiac Spheroidal Droplets With Cardiomyocytes And Cardiac Fibroblasts For Tissue Engineering And Drug Cytotoxicity Studies, Raven El Khoury
Open Access Theses & Dissertations
Engineering is the supreme human endeavor that involves harnessing the scientific understanding of the natural world to design and invent objects to improve the society around us. Biomedical engineering is the implementation of concepts acquired from engineering in biology and medicine that aims to improve human health through the integration of engineering with biomedical sciences. The mission of a biomedical engineer is to develop technologies that help advance the quality of peopleâ??s health using various tools and materials with one passion and goal: making the patient's life longer and easier. Tissue engineering is developed from the field of biomaterials and …
Online/Incremental Learning To Mitigate Concept Drift In Network Traffic Classification, Alberto R. De La Rosa
Online/Incremental Learning To Mitigate Concept Drift In Network Traffic Classification, Alberto R. De La Rosa
Open Access Theses & Dissertations
Communication networks play a large role in our everyday lives. COVID19 pandemic in 2020 highlighted their importance as most jobs had to be moved to remote work environments. It is possible that the spread of the virus, the death toll, and the economic consequences would have been much worse without communication networks. To remove sole dependence on one equipment vendor, networks are heterogeneous by design. Due to this, as well as their increasing size, network management has become overwhelming for network managers. For this reason, automating network management will have a significant positive impact. Machine learning and software defined networking …
Nano-Engineered Soft Magnets: Potential Application In Water Treatment, Hyperthermia And Molecular (Organic) Magnets, Yohannes Weldemariam Getahun
Nano-Engineered Soft Magnets: Potential Application In Water Treatment, Hyperthermia And Molecular (Organic) Magnets, Yohannes Weldemariam Getahun
Open Access Theses & Dissertations
Scrutinizing the remarkable and tunable properties of magnetic materials at a nanoscale size "There's Plenty of Room at the Bottom..." Richard Feynman, this study attempts to find sustainable solutions to some of the deteriorating environmental, health, and energy problems the world is encountering. Due to their simple preparation, surface adaptability, and tunable magnetic and optical properties, magnetic nanoparticles have been extensively investigated in water treatment, cancer therapy, data storage, and more. However, relying on non-reusable and chemical-based treatment agents in water, complex and costly cancer treatment procedures and molecular magnets that operate far below room temperature limited those attempts from …
Fabrication And Characterization Of Germanium Functionalized Porous Nickel Oxide Electrodes For Application In Supercapacitors, Cristina Gonzalez
Fabrication And Characterization Of Germanium Functionalized Porous Nickel Oxide Electrodes For Application In Supercapacitors, Cristina Gonzalez
Open Access Theses & Dissertations
Limited fossil fuel, increasing population, pollution, and climate change are motivating society to use renewable and clean energy techniques. However, the intermittent nature of renewable sources hinders their continuous availability and use. Energy storage devices such as supercapacitors and batteries are essential for sustainable development but their high cost limits its bulk use. The cost of energy storage devices mainly depends on materials, synthesis process and device fabrication. Therefore, low cost 3-D mesoporous nickel germanium fictionalize nickel oxides electrode materials has been developed by using facile fabrication techniques for supercapacitor application. 3-D mesoporous nickel provides the high surface area and …
Direct Potable Reuse Piloting: Optimizing Chloramination, Operationalizing Ultrafiltration, And Understanding Zero Liquid Discharge Options, Marcela Carolina Herrera
Direct Potable Reuse Piloting: Optimizing Chloramination, Operationalizing Ultrafiltration, And Understanding Zero Liquid Discharge Options, Marcela Carolina Herrera
Open Access Theses & Dissertations
A pilot study was deployed at the John T. Hickerson Water Reclamation facility to analyze the viability of high recovery direct potable water reuse (DPR), aiming for zero liquid discharge (ZLD). This pilot consists of a chloramination system and ultrafiltration (UF) as pretreatment for reserve osmosis (RO) followed by UV-peroxide, granular activated carbon (GAC), and concentrate-enhanced recovery reverse osmosis (CERRO). Stabilizing the chloramination and UF system was the first step to ensure efficiency during the downstream processes. The formation of monochloramine is essential for the mitigation of biofouling of the UF membranes. The formation of monochloramine occurs by specific liquid …
The Qualification Of Sealability And Creep Relaxation Of Additively Manufactured Zytel Gaskets For Pem Fuel Cells, Robert Lazarin
The Qualification Of Sealability And Creep Relaxation Of Additively Manufactured Zytel Gaskets For Pem Fuel Cells, Robert Lazarin
Open Access Theses & Dissertations
The purpose of this thesis is to study the feasibility of low-cost additive manufacturing of gaskets for proton exchange membrane fuel cells exposed to extreme temperature conditions ranging from -55°C to 100°C. With the growing popularity and decreasing costs of additive manufacturing technologies, specifically Material Extrusion (ME), research is being conducted to determine the feasibility of ME components. Thermally cycled PEMFCs may exhibit accelerated gasket deterioration, therefore, the mechanical stability of material extruded gaskets following a harsh thermal cycle must be assessed. The feasibility of the material extruded gaskets will be proven by manufacturing optimization and mechanical testing. The target …
Synthetic Data Generation For Intelligent Inspection Of Structural Environments, Noshin Habib
Synthetic Data Generation For Intelligent Inspection Of Structural Environments, Noshin Habib
Open Access Theses & Dissertations
Automated detection of cracks and corrosion in pavements and industrial settings is essential to a cost-effective approach to maintenance. Deep learning has paved the path for vast levels of improvement in the area. Such models require a plethora of data with accurate ground truth and enough variation for the model to generalize to the data, which is notwidely available. There has been recent progress in computer graphics being used for the creation of synthetic data to address the issue of deficient data availability, but it is limited to specific objects, such as cars and human beings. Textures and deformities within …
Investigation Into The Economic Viability Of Industry 4.0 Practices In A Small Start-Up Setting: A Case Study, Joseph Lindley
Investigation Into The Economic Viability Of Industry 4.0 Practices In A Small Start-Up Setting: A Case Study, Joseph Lindley
Open Access Theses & Dissertations
Industry 4.0 has been a hot button topic since the first rumouringâ??s of a fourth industrial revolution taking place in the early 2010s. Since that time many companies have attempted to transform their process, procedures, and systems to become streamlined, efficient, and overall, more profitable. An example of this can be seen in companies such as Microsoft and IBM, Mitsubishi and Siemens who have gained a stronger foothold in their respective markets by their efficient implementation of Industry 4.0. Before we can address how small start-up companies can begin to compete with these behemoths, we must address the question; what …
A Case Study In Design, Construction, And Operation Of A Meromictic Solar Pond In Texas, Usa, Bianca Paola Meneses Brassea
A Case Study In Design, Construction, And Operation Of A Meromictic Solar Pond In Texas, Usa, Bianca Paola Meneses Brassea
Open Access Theses & Dissertations
Over the last four decades, meromictic solar ponds have been the subject of limnological studies and engineering research. A case of practical interest is the salinity gradient solar pond (SGSP). SGSP science and technologies have been systemically advanced in El Paso, Texas. This dissertation aims to share lessons learned in designing, constructing, and operating the El Paso Solar Pond, a NaCl-based solar pond that achieved high-temperature performance over two decades, commencing in 1984. Many of the practical lessons learned have not been published and are thus not readily available in archival journals, and this contribution provides a remedy. The value …
Cad-Based Aerial Trajectory Generation And 3d Mapping For Close-Quarter Inspection, Angel Guillermo Ortega Castillo
Cad-Based Aerial Trajectory Generation And 3d Mapping For Close-Quarter Inspection, Angel Guillermo Ortega Castillo
Open Access Theses & Dissertations
Robotic technologies for inspection purposes of large-scale structures have grown in interest.Such technologies are encouraged to reduce the risk in which human operators are involved and to reduce costs due to downtime of the equipment. In the Energy sector, high interest is placed on power plant components where their correct operation is paramount. This work is inspired by the synthetic vision systems for aerial vehicles that use three-dimensional space (3D) to provide pilots with clear and intuitive means of understanding their flying environment. This work can be separated into three main sections: Trajectory Generation from Computer-Aided Design (CAD) Models, Crack …
Fabrication And Characterization Of Iron-Based Catalysts For The Dehydrogenation Of Fossil Fuels, Victoria Isabel Reyes
Fabrication And Characterization Of Iron-Based Catalysts For The Dehydrogenation Of Fossil Fuels, Victoria Isabel Reyes
Open Access Theses & Dissertations
For a prosperous and sustainable future, hydrogen is an encouraging solution due to its simple transition for industrial decarbonization and synergy for economic development. Paradoxically, current hydrogen production pathways release substantial amount of greenhouse gases into the atmosphere contributing to climate change. To keep up with increasing demand, hydrogen could be produced through microwave-assisted thermocatalytic dehydrogenation of fossil fuels without emitting carbon dioxide. This requires specified catalysts to meet the requirements of hydrogen yield and selectivity. The objective of the present research is to fabricate, characterize, and compare iron-based alumina (FeAl_x O_y) catalysts produced via solution combustion synthesis and iron-based …
Analyzing The Supply Chain Operation Of A Fast-Food Restaurant Using Simulation Modeling And Developing A Cost Estimation Optimization Model In The Disruption Period, Amit Kumar Saha
Open Access Theses & Dissertations
Supply chain operation performance is a much-discussed topic over the last decade which will lead to optimizing the resources required to provide the necessary level of customer service to a specific segment and improve customer service through increased product availability and reduced order cycle time. During disruption in supply chain, performance parameter changes, and the overall supply chain cost at each stage increases. External factors such as labor shortages, delayed and costly supplies, and decreased demand also contribute to this cost. This thesis work presents a research-focused analysis of a small pizza shop, under circumstances that include the loss of …
Magnetic Structures Of Sawtooth Olivines Mn2six 4 (X = S, Se) Determined Through Neutron Powder Diffraction, Melaku Sisay Tafere
Magnetic Structures Of Sawtooth Olivines Mn2six 4 (X = S, Se) Determined Through Neutron Powder Diffraction, Melaku Sisay Tafere
Open Access Theses & Dissertations
In olivine chalcogenide Mn2SiX 4 (X = S, Se) compounds, the Mn lattice produces a sawtooth, which is of critical significance in magnetism due to the potential for manifesting at bands in the magnon spectrum, a crucial component in magnonics. The compounds Mn2SiS4 and Mn2SiSe4 in Mn2SiX 4 family undergo antiferromagnetic phase transitions at T â?? 85 K and â?? 66 K, respectively, as determined from the specific heat, Cp(T). The average and local crystal structuresare determined using synchrotron X-ray, neutron diffraction, and X-ray total scattering data followed by Rietveld and pair distribution function (PDF) analysis. It is found from …
Hybrid Model For Making Decision Methods In Wireless Sensor Networks Through Neuro-Fuzzy Inference System, Martha Lucia Torres
Hybrid Model For Making Decision Methods In Wireless Sensor Networks Through Neuro-Fuzzy Inference System, Martha Lucia Torres
Open Access Theses & Dissertations
Considering the complexity and multiple alternatives for technology decisions in Wireless Sensor Networks (WSNs), a multicriteria selection method (MCDM) is an appropriate approach for choosing the best option in technical projects. Purely quantitative decision-making procedures have currently been created based on client requirements and recommendations from industry professionals in many domains. In this context, implementation and operational costs could be increasing due to technical problems and additional processes. In order to prevent future difficulties and obtain a more accurate technology selection, a new method was being developed to involve qualitative and quantitative parameters taken from real scenarios and technical literature …
Identifying Particulate Matter Spatial Variation In The El Paso Del Norte Region Using Land-Use Regression Modeling And Data Obtained From A Network Of Low-Cost Sensors, Leonardo Demetrio Vazquez-Raygoza
Identifying Particulate Matter Spatial Variation In The El Paso Del Norte Region Using Land-Use Regression Modeling And Data Obtained From A Network Of Low-Cost Sensors, Leonardo Demetrio Vazquez-Raygoza
Open Access Theses & Dissertations
The emergence and rise in popularity of low-cost sensors for atmospheric observation aresetting a new precedent in identifying emission hotspots and providing high-resolution spatial and temporal data. Furthermore, low-cost sensors are becoming popular among institutions and the public, allowing community scientists to become more involved in air quality monitoring. However, concerns about the accuracy and precision of low-cost sensors have been questioned. Most recent research has focused on the utility of real-time monitoring and calibration requirements for these sensors. A low-cost monitoring project has deployed sensors in the El Paso del Norte region in low and high annual average daily …
Continuous Moisture Measurement During Pavement Foundation Construction: Laboratory Measurements, Isaac Esteban Zuniga
Continuous Moisture Measurement During Pavement Foundation Construction: Laboratory Measurements, Isaac Esteban Zuniga
Open Access Theses & Dissertations
Moisture content directly affects all properties of subgrade materials. A rapid, continuous, and accurate technique to determine moisture content during subgrade construction is the next step needed to improve the mechanistic-based quality of pavement foundations. In this study, six geomaterials were compacted to standard/modified proctor specifications and subjected to laboratory measurements to study the variations in their electromagnetic and electric properties with moisture content. The relationships between the seismic modulus, unconfined compressive strength, lightweight deflectometer, and moisture content for the same geomaterials were also established. Large-scale replicate specimens were also compacted and subjected to numerous measurements. The dielectric constant measured …
Determination Of Oxidation-Reduction Potential And Iron Chemistry For Solutions Generated During The Hydrometallurgical Extraction Of Copper, Jiahao Xu
Open Access Theses & Dissertations
Oxidation-reduction potential (ORP) based on iron chemistry is one of the key operating parameters during the hydrometallurgical extraction of copper. A novel ORP equation was developed previously only based on the variables of temperature and nominal ferric/ferrous ratio to predict the redox potential of the quaternary H2SO4-Fe2(SO4)3-FeSO4-H2O system. However, its applicability in more complex acidic iron sulfate solutions during the hydrometallurgical extraction of copper with different temperatures, acidic concentration, cupric concentration, nominal ferric/ferrous ratio, and total and l iron concentration has not been extended and validated. This work evaluates the applicability of novel oxidation-reduction potential equation in the H2SO4-Fe2(SO4)3-FeSO4-H2O and …
Compact Electrospray Propulsion Systems For Small Form-Factor Satellites: An Orbital Performance Survey & Platform Design, Alberto Meza
Compact Electrospray Propulsion Systems For Small Form-Factor Satellites: An Orbital Performance Survey & Platform Design, Alberto Meza
Open Access Theses & Dissertations
Over the past decades, small form-factor satellites such as CubeSats have remained as one of the most accessible platforms to reach space for universities, research institutions, private and governmental entities to perform a wide range of missions. This paper presents a survey into the design and implementation of an electrospray rail thruster, to be integrated to the CubeSat platform. The design investigated features propellant tanks for each individual thruster embedded inside the rail of a standard 1U CubeSat. The capabilities of utilizing the electrospray thruster as an attitude & determination control system was also investigated in which, a pointing accuracy …
Exploring The Effect Of Environmental Degradation On The Shape Memory Properties Of Polymers, Jorge Mario Avila
Exploring The Effect Of Environmental Degradation On The Shape Memory Properties Of Polymers, Jorge Mario Avila
Open Access Theses & Dissertations
A key detriment of the use of polymers by our society is the negative effect this material class has had on the environment. A category of polymers known as shape memory polymers (SMP)s have the ability to return to a programmed original shape form after deformation to a temporary shape by using stimuli such as temperature, electrical pulses and even magnetism. The shape memory effect allows for some polymers to heal if they are damaged. This ability to heal means that components made from these materials can be reused rather than thrown away if they are damaged. The work presented …
Using Ultrasonication For The Improvement Of Grade And Recovery In Molybdenum Sulfide Flotation, Wayne Alexander Campbell
Using Ultrasonication For The Improvement Of Grade And Recovery In Molybdenum Sulfide Flotation, Wayne Alexander Campbell
Open Access Theses & Dissertations
Experimentation was performed on molybdenite slurry by using ultrasonication to elucidate the effects of ultrasonic-induced bubble cavitation on the grade, recovery, and gangue reduction during small-scale flotation tests and was followed by a topographical analysis of quartz particles using SEM. Ultrasonic waves at 20-80 kHz that propagate through a liquid medium cause microbubbles to form, grow, and implode. The cavitation bubble's implosion causes brief extreme local conditions where temperatures can reach 5,000 K and pressures of 1,000 bar. The resulting microjets create mechanical and chemical changes to the system and were directed at improving flotation dynamics in these experiments. Through …
Transportation Asset Management For The Electric Road System, Kamalen Maria Santos Diaz
Transportation Asset Management For The Electric Road System, Kamalen Maria Santos Diaz
Open Access Theses & Dissertations
Electric road systems (ERS) have been presented as a new solution towards a sustainable transportation future, fueling the widespread adoption of electric vehicles by eliminating range anxiety, reducing battery size, and being regional friendly. These systems consist of four components: electric power supply, roads, vehicles, and operations. Much of the early research conducted on ERS has been on how to initially construct these systems by focusing on the first three components, however, there is limited knowledge on how ERS will impact traditional road operations after the systems are in place. Transportation Asset Management (TAM), a major focus within the transportation …
Direct Ink Write And Thermomechanical Characterization Of Thermoset Composites, Sergio Dante Favela
Direct Ink Write And Thermomechanical Characterization Of Thermoset Composites, Sergio Dante Favela
Open Access Theses & Dissertations
This research will be divided into two sections. The first section discusses direct ink writing and thermomechanical characterization for thermoset composites. The thermoset ink is prepared with fillers aiding the printing process by modifying the rheology of the ink and geometry retention by allowing for the part to have an initial UV cure step. Three specimen formulations with different weight percentages were printed by material extrusion in the shape of tensile specimens following ASTM standard D638 to characterize the mechanical properties at room temperature, 100â?? and 200â??. Furthermore, the ink resin was characterized through DSC, TGA, and rheology testing. The …
Generation Of Phase Transitions Boundaries Via Convolutional Neural Networks, Christopher Alexis Ibarra
Generation Of Phase Transitions Boundaries Via Convolutional Neural Networks, Christopher Alexis Ibarra
Open Access Theses & Dissertations
Accurate mapping of phase transitions boundaries is crucial in accurately modeling the equation of state of materials. The phase transitions can be structural (solid-solid) driven by temperature or pressure or a phase change like melting which defines the solid-liquid melt line. There exist many computational methods for evaluating the phase diagram at a particular point in temperature (T) and pressure (P). Most of these methods involve evaluation of a single (P,T) point at a time. The present work partially automates the search for phase boundaries lines utilizing a machine learning method based on convolutional neural networks and an efficient search …
Security Analysis And Implementation Of Dnp3 Multilayer Protocol For Secure And Safe Communication In Scada Systems, Isaac Monroy
Security Analysis And Implementation Of Dnp3 Multilayer Protocol For Secure And Safe Communication In Scada Systems, Isaac Monroy
Open Access Theses & Dissertations
When SCADA systems were first introduced into society, a lot of manpower was required for monitoring and controlling devices within critical infrastructures. With the increasing demand for services and growing systems, a need arose to automate the monitoring and controlling tasks. This led to introduction of networks into SCADA systems to enhance monitoring and control capabilities, that can scale with system size and requirements. But this introduction of network layer along with its advantages, also introduced a new threat surface which exposed multiple vulnerabilities within the system that can exploited to launch attacks, that led to the integration of security …
Fabrication, Microstructure And Mechanical Characterization Of Crvnbtaw High Entropy Alloy Coatings Using Magnetron Sputtering, Jorge Quezada
Fabrication, Microstructure And Mechanical Characterization Of Crvnbtaw High Entropy Alloy Coatings Using Magnetron Sputtering, Jorge Quezada
Open Access Theses & Dissertations
In this project a CrVNbTaW high entropy alloy was evaluated. The samples were made using radio frequency magnetron sputtering and were made under similar conditions. The deposition parameters were explored to find the ideal deposition process. The process included a pressure from 0.1-2mTorr, 600C, 1 hour duration, at 100W power to guns, and constant argon flow. The samples were fabricated under similar parameters using silicon steel and sapphire substrates. The samples were analyzed and characterized using X-ray diffraction, scanning electron microscopy, atomic force microscopy, nanoindentation and corrosion testing. Based on these results we were able to get a better understanding …
Cryogenic Flow Boiling Heat Transfer On Additively Manufactured Liquid Rocket Engine Cooling Channels, Debra Jazmin Ortega
Cryogenic Flow Boiling Heat Transfer On Additively Manufactured Liquid Rocket Engine Cooling Channels, Debra Jazmin Ortega
Open Access Theses & Dissertations
The enhancement of flow boiling heat transfer is critical because it can solve thermal management issues seen across all engineering and manufacturing applications. Even though advancements are being made, more studies are needed to understand the behavior of forced convective boiling further.Currently, there are four major issues in the field of regenerative cooling of liquid rocket engines. 1. The cooling channels are typically manufactured using conventional machining, while aerospace industries are currently exploring the additive manufacturing approach. 2. The experimental critical heat flux values for cryogenic fluids are either lower or very close to the model predictions; however, the effect …