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Home Care Work Of Caregivers For Mexican American Adults With Dementia: A Culturally Informed Model Integrating Work System Analyses And Health Disparities Research Framework, Laura Cristina Tovar Felix Aug 2024

Home Care Work Of Caregivers For Mexican American Adults With Dementia: A Culturally Informed Model Integrating Work System Analyses And Health Disparities Research Framework, Laura Cristina Tovar Felix

Open Access Theses & Dissertations

Dementia is an umbrella term for different diseases such as Alzheimer's, vascular dementia, Lewy body, frontotemporal, and mixed dementias. Dementia is caused by a variety of diseases that cause damage to brain cells interfering with the ability of brain cells to communicate between each other. Dementia is associated with different types of brain cell damage in a specific region of the brain (What Is Dementia?, 2024).Dementia affects 55 million people worldwide, where the most affected population is the low-income and the middle-income countries. (Greenblat, 2023). Every 20 years the number almost double, and by 2039 is estimated to reach 78 …


Comparative Study Of Hydrogen Embrittlement On Ebm Inconel 718 As-Built And Hiped Specimens, Julio Cesar Diaz Aug 2024

Comparative Study Of Hydrogen Embrittlement On Ebm Inconel 718 As-Built And Hiped Specimens, Julio Cesar Diaz

Open Access Theses & Dissertations

This study investigates the effects of hydrogen embrittlement (HE) on Inconel 718 parts produced using Electron Beam Melting (EBM) with a spot melting scanning strategy, focusing on analyzing the material's microstructure and mechanical properties. This research aims to understand the impact of hydrogen charging on both as-built and Hot Isostatically Pressed (HIPed) samples of Inconel 718, a material widely used in high-stress applications in aerospace and energy industries.The methodology included detailed characterization using techniques such as Electron Backscatter Diffraction (EBSD), Transmission Electron Microscopy (TEM), and Scanning Electron Microscopy (SEM) followed by hydrogen charging of EBM-fabricated Inconel 718 samples. Mechanical testing, …


Development Of 3d Human Cardiovascular And Cancer Tissue Model Within A Self-Driven Microfluidic Platform For Preclinical Drug Screening, Aibhlin Alexis Esparza Aug 2024

Development Of 3d Human Cardiovascular And Cancer Tissue Model Within A Self-Driven Microfluidic Platform For Preclinical Drug Screening, Aibhlin Alexis Esparza

Open Access Theses & Dissertations

According to the American Heart Association and World Health Organization, cardiovascular diseases (CVDs) are the leading cause of death worldwide. Monolayer cell culture (2D) and animal models are conventional methods to study CVDs, however, they limit researcherâ??s ability to simulate the human cardiovascular cellular microenvironments and accurate predication of pharmaceutical drug responses. Human induced pluripotent stem cell derived cardiomyocytes (hiPSC-CMs), biomaterials, and microfluidic technologies can be combined to create a controlled, reproducible 3D platform to study physiologically-relevant cellular responses to biochemical and physical changes in the microenvironment. My dissertation work demonstrates the development of novel self-driven microfluidic devices designed with …


Using Causal Inference To Understand Public Perception Towards Electric Vehicle Adoption, Jesus Alejandro Gutierrez Araiza Aug 2024

Using Causal Inference To Understand Public Perception Towards Electric Vehicle Adoption, Jesus Alejandro Gutierrez Araiza

Open Access Theses & Dissertations

Why despite all efforts to promote Electric Vehicles (EVs) as an alternative transportation method through strategies such as tax credits on unit purchasing or long-term environmental benefits communication, its market penetration has not reached the expected goals in the United States? Even though there have been important advancements in the EV technical perspective and financial EV purchasing incentives, the final EV customers still face barriers on their scenarios that do not allow them to purchase this type of contemporary transportation means. Not understanding their local barriers could be a mistake that could reduce EVA expectations in the country and keep, …


Flow-Shop Scheduling Optimization Through Discrete-Event Simulation And Neural Networks., Jesus Ricardo Herrera Garfio Aug 2024

Flow-Shop Scheduling Optimization Through Discrete-Event Simulation And Neural Networks., Jesus Ricardo Herrera Garfio

Open Access Theses & Dissertations

Industrial developments over the past few decades have transformed manufacturingprocesses, emphasizing the necessity for efficient scheduling systems. The shift from manual scheduling to automated and optimized systems has underscored the need for innovative approaches to improve production efficiency. Scheduling optimization of manufacturing systems is critical to improve operational efficiency. Typically, these scheduling problems become challenging because they involve coordinating various production tasks, resource management, and makespan minimization. These challenges are particularly evident in flow-shop manufacturing systems, where the operation sequencing significantly impacts overall performance. The main objective of this manuscript is to present the methodology followed to optimize the schedule …


Reactive Processing Of Hf-Nb-Ti-Ta Melts Into A B4c/C Packed Bed, Laura Leticia Sandoval Aug 2024

Reactive Processing Of Hf-Nb-Ti-Ta Melts Into A B4c/C Packed Bed, Laura Leticia Sandoval

Open Access Theses & Dissertations

The reactivity of liquid Hf-Nb-Ti-Ta alloy in B4C/C packed bed to form boride-carbide precipitates for ultra-high temperature ceramics was investigated at 2800 K. The objectives were to predict the thermodynamic phases formed and verify them with microstructural characterization. A pseudo-isopiestic technique was used to significantly lower the oxygen potential as the liquid Hf alloy infused and reacted into a B4C packed bed within a graphite enclosure. The technique had a low temperature region (at 1300 K) to control the oxygen potential with a Y-Al/Y2O3-Al2O3/carbide mixture as a liquid Hf alloy at 2800 K and reacted with B4C/C. In addition, any …


Advancing Understanding Of Opinions, Perceptions, And Knowledge In Underrepresented Communities In The El Paso Region To Promote Electric Vehicles And Electrified Infrastructure Use To Reduce Environmental Impacts, Liliana Lozada-Medellin Jul 2024

Advancing Understanding Of Opinions, Perceptions, And Knowledge In Underrepresented Communities In The El Paso Region To Promote Electric Vehicles And Electrified Infrastructure Use To Reduce Environmental Impacts, Liliana Lozada-Medellin

Open Access Theses & Dissertations

As the transportation and automotive industries continue growing, environmental and human health impacts remain a growing concern for planners, policy-makers, constructors, and the public as well (Krause et al., 2013; Larson et al., 2014). Although Electric Vehicles (EVs) are entering the market as a green technology solution to counteract greenhouse gas (GHG) emissions from internal combustion engine vehicles (ICEVs), there are still barriers that need to be overcome for widespread diffusion and adoption as the best solution. These include disseminating basic information about the technology for public awareness, considering equity concerns, and ensuring equitable access to infrastructure for all (L. …


Mav Localization In Gps-Denied Environments And Synthetic Data Collection In Challenging Simulated Conditions, Julio A. Reyes Munoz May 2024

Mav Localization In Gps-Denied Environments And Synthetic Data Collection In Challenging Simulated Conditions, Julio A. Reyes Munoz

Open Access Theses & Dissertations

The development of unmanned aerial systems presents an opportunity for conducting industrial inspections in environments where traditional navigation systems, such as the Global Navigation Satellite System (GNSS), are compromised. This dissertation investigates the implementation of a micro aerial vehicle (MAV) capable of autonomous data acquisition in complex, GNSS-degraded industrial settings. The primary challenge addressed is the robust localization of MAVs, a critical aspect in ensuring reliable operation under varying and uncertain environmental conditions.

The work is divided into two main parts. The first part focuses on the design and integration of a MAV system specifically for power plant inspections in …


Analysis Of Additively Manufactured Inconel 718 Combustion Behavior In Promoted Oxygen Environments, Dominic George Dieguez May 2024

Analysis Of Additively Manufactured Inconel 718 Combustion Behavior In Promoted Oxygen Environments, Dominic George Dieguez

Open Access Theses & Dissertations

Promoted combustion testing is a vital tool for engineers to establish the combustion and flammability characteristics of materials (metallic or otherwise) in oxygen enriched environments. Historically, much of the established data for metallic promoted combustion has been with regards to materials in their cast and wrought forms. However, with the emergence of additive manufacturing as a preferred method of fabrication, the need exists to evaluate how metals in that form behave. Recent testing has demonstrated that even if a metal or alloy is nominally the same with regards to chemistry, flammability between samples in the wrought form can differ significantly …


Microstructural Characterization And Oxidation Behavior Of Al-Cu-Ni-Mn And Al-Cu-Ni-Mn-Si Non-Body Centered Cubic High Entropy Alloys, Mckenna Mae Lin Hitter May 2024

Microstructural Characterization And Oxidation Behavior Of Al-Cu-Ni-Mn And Al-Cu-Ni-Mn-Si Non-Body Centered Cubic High Entropy Alloys, Mckenna Mae Lin Hitter

Open Access Theses & Dissertations

High entropy alloys (HEA) differ from traditional alloying systems because five elements are mixed in equi-atomic proportions, as opposed to having one main principal element. As a result of exploring this new method of alloying, it was found that high entropy alloys demonstrate exceptional mechanical properties, an example being oxidation resistance, and are capable of enduring elevated temperatures. Seeing the potential that this new area of interest contains, studies involving a combination of elements to form various HEA have been performed. Most refractory metals are body-centered cubic and possess extremely high melting temperatures, so they are regularly considered when designing …


Microwave Emission Model Parameter Tuning For Surface Soil Moisture Retrieval Using Uav-Mounted Dual Polarization L-Band Radiometer, Santiago Hoyos Echeverri May 2024

Microwave Emission Model Parameter Tuning For Surface Soil Moisture Retrieval Using Uav-Mounted Dual Polarization L-Band Radiometer, Santiago Hoyos Echeverri

Open Access Theses & Dissertations

Surface soil moisture retrieval from L-band brightness temperature has been developed for the past decades due to multiple beneficial characteristics of 1-2 GHz frequency bands for remote sensing of the environment. Numerous microwave emission models have been proposed for tower and satellite-based operations with successful retrieval of surface soil moisture and vegetation water content. As a result of the development of cost-effective and low-mass microwave L-band radiometers such as the Portable L-band Radiometer (PoLRa), surface soil moisture surveying traditionally developed by satellite missions SMOS and SMAP can now be developed at local scales, bringing these operations to commercial small unmanned …


Selective Transfection Of A Transferrin Receptor-Expressing Cell Line With Dna-Lipid Nanoparticles And Synthesis Of Parasite-Derived Glycans As Biomarkers For Leishmaniasis, Irodiel Vinales Lozano May 2024

Selective Transfection Of A Transferrin Receptor-Expressing Cell Line With Dna-Lipid Nanoparticles And Synthesis Of Parasite-Derived Glycans As Biomarkers For Leishmaniasis, Irodiel Vinales Lozano

Open Access Theses & Dissertations

Despite notable progress in lipid nanoparticle (LNP)-mediated gene delivery, achieving selective transfection of specific cell types, such as cancer cells, remains a significant hurdle, hindering the advancement of innovative gene therapies. In this study, we engineered an LNP formulation encapsulating plasmid DNA (pDNA) encoding the monomeric Green Lantern (mGL) fluorescent reporter protein. The DT7 peptide ligand targeting human transferrin receptor 1 (hTfR1) was also conjugated to the LNP surface for targeted delivery to hTfR1-expressing cells. Optimization of LNP composition yielded favorable particle diameter, ζ-potential, yield, and pDNA encapsulation efficiency. Evaluation of transfection selectivity using a panel of two engineered cell …


Effect Of Patient Specific Blood Biomarkers On Nanoparticle - Cell Interactions, Veronica Gabriela Contreras May 2024

Effect Of Patient Specific Blood Biomarkers On Nanoparticle - Cell Interactions, Veronica Gabriela Contreras

Open Access Theses & Dissertations

Nanoparticles are currently known to be a promising material class for bio-applications in drug delivery and vaccine development. Using gold nanoparticles of varied sizes, in this case 45 and 100 nanometers as a model nanomaterial system, we investigated how patients' blood physiology and chemistry (such as solute, protein, lipid levels) affect the biological response to bionanomaterials. When nanoparticles are injected into the body, biomolecules in the blood adsorb to the nanoparticle's surface to form a biomolecular corona that is specific to the patient's unique blood composition. This biomolecular corona is important because it affects the in vivo fate and biodistribution …


Effect Of The Microstructure On The Corrosion Behavior Of Alcunimn And Alcunimnsi High Entropy Alloys In A 3.5wt% Nacl Solution, Celine Chiong May 2024

Effect Of The Microstructure On The Corrosion Behavior Of Alcunimn And Alcunimnsi High Entropy Alloys In A 3.5wt% Nacl Solution, Celine Chiong

Open Access Theses & Dissertations

In this study, the AlCuNiMn and AlCuNiMnSi high entropy alloys (HEAs) are investigated to characterize the effect of Si addition and subsequent annealing treatments on the corrosion behavior in a 3.5wt% NaCl solution at room temperature. The microstructure evolution from the as-received condition and after annealing at 600°C, 800°C, and 1000°C for 24 hours in air is examined. The microstructural transformation of HEAs is extensively reported in the literature. However, its impact on the corrosion resistance of HEAs has not received the same attention. In this study, an increase in the annealing temperature of the base AlCuNiMn alloy improved the …


Comparative Analysis Of The Effects Of Post Processing On The Flexural Fatigue Endurance Of Additively Manufactured Ti-6al-4v, Cristian Banuelos May 2024

Comparative Analysis Of The Effects Of Post Processing On The Flexural Fatigue Endurance Of Additively Manufactured Ti-6al-4v, Cristian Banuelos

Open Access Theses & Dissertations

This study delves into analyzing the effects of various machining techniques on the flexural fatigue life of Ti-6Al-4V L-PBF specimens. The fatigue life and fracture behavior of specimens subjected to milling, grinding, polishing, and abrasive media blasting were compared. The findings reveal significant differences in the fatigue resistance between machined and non-machined parts. This study contributes to the understanding of the effects of post-processing on the durability of L-PBF manufactured components, offering insights for enhancing their application in critical aerospace and biomedical applications.


Smart Public Transportation And Mobility Hub Design In El Paso, Jiri Vojtisek May 2024

Smart Public Transportation And Mobility Hub Design In El Paso, Jiri Vojtisek

Open Access Theses & Dissertations

This thesis explores the potential of a Smart Public Transportation concept and mobility hub design as tools to mitigate the growing trend of transportation issues, such as traffic congestion, reliance on privately owned vehicles, or unattractive public transportation. Consequently, residentsâ?? lives are negatively affected by excessive noise, air pollution, and travel delays, leading to increased safety risks, lost productivity, and a lower quality of life. Considering these challenges, the study begins by analyzing the current state of public transportation in El Paso. Next, it introduces a toolkit from the Smart City concept, followed by case studies of best practices of …


Using Genetic Algorithm And Geographic Information System For Equity-Driven Transportation Planning And Analysis, Emiliano Del Rio Reyes May 2024

Using Genetic Algorithm And Geographic Information System For Equity-Driven Transportation Planning And Analysis, Emiliano Del Rio Reyes

Open Access Theses & Dissertations

Efforts to address equitable access in public transit planning have gained momentum, spurred by incentives for Metropolitan Planning Organizations (MPOs) and State Departments of Transportation (DOTs). However, traditional strategies often fall short of meeting the needs of disadvantaged communities, particularly in underserved areas. This study presents a pioneering methodology leveraging Genetic Algorithms (GA) and Geographic Information Systems (GIS) to optimize bus stop placement, aiming to enhance equitable access in public transit systems. Focusing on Route 16 of Sun Metro in El Paso, Texasâ??a critical feeder route linking the Westside Transit Center to Upper Valley neighborhoodsâ??the research commences with a comprehensive …


Laser Powder Directed Energy Deposition (Lp-Ded) Inconel 718: Laser Power And Heat Treatment Effect On Microstructure And Mechanical Properties, Dana Victoria Godinez May 2024

Laser Powder Directed Energy Deposition (Lp-Ded) Inconel 718: Laser Power And Heat Treatment Effect On Microstructure And Mechanical Properties, Dana Victoria Godinez

Open Access Theses & Dissertations

This study examines the microstructure and mechanical properties (tensile, hardness, and fatigue endurance) of laser powder-directed energy deposition (LP-DED) printed specimens with varying deposition parameters. Five samples with power inputs ranging from 350 to 2620W, all of similar thicknesses, were evaluated to enable a direct comparison. The varying specimens were heat treated, including stress relief, hot isostatic pressing, solution, and two-step aging. The resulting microstructures and their corresponding hardness values were compared at each heat treatment stage. The fully heat-treated specimens' tensile properties and fatigue life were also examined and compared. Key findings of this study indicate that complete heat …


Development Of A Digital Engineering Testing Framework For Cubesat Applications, Javier Alberto Martell May 2024

Development Of A Digital Engineering Testing Framework For Cubesat Applications, Javier Alberto Martell

Open Access Theses & Dissertations

Digital Engineering (DE) is playing an important and expanded role in todayâ??s industry. As engineering systems become more and more complex with each new iteration, the need for a more efficient and agile methodology for project management and development is needed. The SleeperSat-1 (SPST-1) is a Modular Open System Architecture (MOSA) type of small satellite being developed by the UTEP Aerospace Center. The SPST-1 will mostly use digital engineering tools for its lifecycle research and development. CubeSats require rigorous environmental testing not only to ensure the success of the mission, but also to ensure the safety of the crew, space …


Biofabrication Of Human Tissue-On-A-Chip Models Using Engineered Biocompatible Electrospun Scaffolds, Zayra Naomi Dorado May 2024

Biofabrication Of Human Tissue-On-A-Chip Models Using Engineered Biocompatible Electrospun Scaffolds, Zayra Naomi Dorado

Open Access Theses & Dissertations

This study explored the adoption of furfuryl gelatin (F-gelatin) based electrospun scaffolds compared with poly-caprolactone (PCL) as promising biomaterials for tissue engineering applications. Tissue-on-a-chip models, incorporating F-gelatin and PCL electrospun scaffolds, offer promising avenues for healthy and disease-in-vitro tissue models that can be explored to investigate underlying physiological mechanisms involved in disease development. Previous research has demonstrated the cytocompatibility of F-gelatin when used for modifying implant surfaces and tissue repair applications [1]. Our earlier published works have also successfully utilized F-gelatin for in-vitro cardiac tissue engineering [2][3]. We designed F-gelatin and PCL electrospun scaffolds to replicate the native tissue extracellular …


Routing Opportunities For Commercial Crossings Between El Paso And Juarez, Marek Musil May 2024

Routing Opportunities For Commercial Crossings Between El Paso And Juarez, Marek Musil

Open Access Theses & Dissertations

This thesis explores the topic of commercial movements between the El Paso and Ciudad Juarez road networks and the implications of the possible changes in their routing. This area houses several ports of entry, which present one of the busiest commercial and personal border crossings in the whole nation. The primary focus was to evaluate the recently proposed reconstruction scenario of removing trucks from the Bridge of the Americas and study the impacts on the flows throughout the other ports. The chosen tool to support the analysis is a mesoscopic simulation software called DynusT, which is capable of modeling the …


Understanding The Limits Of Deep Packet Inspection For Network Traffic Classification, Herman Ramey May 2024

Understanding The Limits Of Deep Packet Inspection For Network Traffic Classification, Herman Ramey

Open Access Theses & Dissertations

We present our human network application labeling system that contributes a new level of distinction between the network traffic that should be labeled from the network traffic that should not be labeled. This distinction improves the label accuracy of the training data set produced from the human labeled data and will subsequently improve the performance of supervised machine learning classifiers used for network traffic classification. This system also allows for the human network user to label traffic, with little effort, in a manner consistent with normal network usage, i.e., no need for a contrived experiment. Lastly, we use human supplied …


Prediction Modeling Of Foreign Object Impact Debris On Aircraft Through Digital Engineering, Luis Eduardo Rodriguez May 2024

Prediction Modeling Of Foreign Object Impact Debris On Aircraft Through Digital Engineering, Luis Eduardo Rodriguez

Open Access Theses & Dissertations

The contribution of the research made is derived into two sections. The first topic discusses the prediction modeling of Foreign Object debris (FOd) impact on aircraft structures through the use of digital engineering. The program used in this project is Ansys Explicit Dynamics to evaluate the stress and strain caused by the initial conditions of flight trajectory and impact created from FOd found inside of aircraft structures. The prediction modeling consists of creating a repetition of simulations with different FOds to evaluate the damage created to subsystems of the wing bay such as the fuel system and internal structures. The …


Feasibility Study For The Detection Of Damage To Composite Overwrapped Pressure Vessels With Phase Array Ultrasonic Testing, Jordan Scott Hitter May 2024

Feasibility Study For The Detection Of Damage To Composite Overwrapped Pressure Vessels With Phase Array Ultrasonic Testing, Jordan Scott Hitter

Open Access Theses & Dissertations

When discussing the field of Nondestructive Examination, there are various techniques and instrumentation that can be utilized for analysis of components. However, with newer technology and the development of newer forms of technique, it is critical to explore exactly how these can be applied. This work will aim to explore one newer technique, Phased Array Ultrasonic Testing, and determine the viability of its use for examining Composite Overwrapped Pressure Vessels (COPVs). Currently, the types of vessels have been used in a variety of ways such as in transportation vehicles. More notably, these vessels are used in aerospace applications hence the …


Earth Abundant Catalyst For Evironmental Sustainability Applications, Javier Hernandez May 2024

Earth Abundant Catalyst For Evironmental Sustainability Applications, Javier Hernandez

Open Access Theses & Dissertations

The development of experimental methodologies for synthesizing a diverse range of metallic and metal oxide nanoparticles tailored for sustainable water treatment applications was investigated. These nanoparticles are prepared using environmentally friendly and scalable synthesis methods, underscoring their potential for large-scale production. Synthesized nanoparticles are harnessed for various processes, including catalysis and electrocatalysis, with a primary objective of degrading and removing organic pollutants from water. Key to this research is the encapsulation of nanoparticles within solid supports. Multiple methodologies are explored to engineer supports that ensure nanoparticle stabilization, monodispersion, and prevent unintended release into the environment. Two alternative approaches were evaluated …


Bcl2 Mediated Targeted Drug Delivery For The Treatment Of Kidney Fibrosis And Stomach Cancer, Humayra Afrin May 2024

Bcl2 Mediated Targeted Drug Delivery For The Treatment Of Kidney Fibrosis And Stomach Cancer, Humayra Afrin

Open Access Theses & Dissertations

Apoptosis, the programmed death of cells, is primarily regulated by a delicate balance between pro-apoptotic and anti-apoptotic signals. The Bcl-2 (B-cell lymphoma 2) family of proteins acts as anti-apoptotic agents, promoting cell survival. Dysregulation of these proteins is a common occurrence in conditions such as cancer and fibrosis, where overexpression of anti-apoptotic members can foster tumor cell survival and fibroblast activation. In this study, our aim was to explore the therapeutic potential of Bcl-2 inhibitors, both as a small molecule (specifically Navitoclax (Navi)), inhibitor and as Bcl-2 siRNA, for targeted treatment. Intravenous administration of Navi often leads to thrombocytopenia, necessitating …


Sulfonated Polyethersulfone Membranes For Electrodialysis Desalination And The Influence Of Solvent Evaporation On Current Efficiency, Salinity Reduction, And Permselectivity, Li Chen May 2024

Sulfonated Polyethersulfone Membranes For Electrodialysis Desalination And The Influence Of Solvent Evaporation On Current Efficiency, Salinity Reduction, And Permselectivity, Li Chen

Open Access Theses & Dissertations

The high cost of ion exchange membranes significantly limits the public application of electrodialysis. The research of novel, inexpensive ion exchange membranes is essential to developing and applying electrodialysis desalination technology. This research focuses on fabricating cation exchange membranes with polyethersulfone (PES) and sulfonated PES (sPES) for water treatment. N-Methyl-2-Pyrrolidone (NMP) was used as an organic solvent to dissolve PES. After different solvent evaporation times were optimized from 0 hr to 24 hr, those membranes were formed through the phase inversion technique. The performance results show that the PES membranes performed the best when the solvent evaporated at 3 hr, …


Energy Optimization In Pneumatic Systems Using Ens-200 Energy Saving Trainer, Maha Guru Shankar Perumal May 2024

Energy Optimization In Pneumatic Systems Using Ens-200 Energy Saving Trainer, Maha Guru Shankar Perumal

Open Access Theses & Dissertations

Various industries such as manufacturing and assembly, the automotive sector, printing and paper handling, packaging, aerospace, etc., widely use pneumatic systems for a variety of operations. Enterprises use pneumatic systems for cost-effectiveness, reliability, and simplicity. However, they also have certain inefficiencies, leading to high operating costs and reduced efficiency in various applications. The focus of this research is on energy optimization in pneumatic systems to improve efficiency in industrial applications, minimize energy waste, and reduce operational costs. The best practices for enhancing energy efficiency in pneumatic systems were proper system design, pressure regulation, leak detection and repair, energy-efficient components, and …


Physics-Guided Scan Paths Optimization For Controlled Microstructure In Laser Powder Bed Fusion, Augustine Twumasi May 2024

Physics-Guided Scan Paths Optimization For Controlled Microstructure In Laser Powder Bed Fusion, Augustine Twumasi

Open Access Theses & Dissertations

Laser Powder Bed Fusion (L-PBF) is a renowned additive manufacturing technique, celebrated for its capability to construct intricate metal components with remarkable precision. However, one of the main challenges with L-PBF is the formation of complex microstructures, which can significantly impact the final material properties. To address this issue, our study proposes a physics-guided and machine-learning-aided approach to optimize scan paths for achieving desired microstructure outcomes, such as the generation of equiaxed grains that enhance material properties. By using phase-field modeling, a physics-based computational method, we gain insights into microstructure evolution. To reduce computational costs, we train a surrogate machine-learning …


Effect Of Multiple Machine Configurations And Wall Thickness On Microstructure And Microhardness Of Laser Powder Bed Fusion (L-Pbf) Additively Manufactured Heat-Treated Inconel 718 Products, Anannya Doris Dec 2023

Effect Of Multiple Machine Configurations And Wall Thickness On Microstructure And Microhardness Of Laser Powder Bed Fusion (L-Pbf) Additively Manufactured Heat-Treated Inconel 718 Products, Anannya Doris

Open Access Theses & Dissertations

This research examined thin section prototypes having seven nominal thicknesses ranging from 0.1 to 2.0 mm, composing a series of geometric feature build plates manufactured by multiple laser powder bed fusion (L-PBF) machine configurations. The build plates and thin section feature prototypes underwent a full heat treatment cycle per established standards: anneal at 1066°C, SR+HIP at 1163°C, and fully treat-treated by combining SR+HIP+solution treatment at 1066°C and double aging treatment at 760°C and 680°C, respectively. The fully heat-treated (FHT) Inconel 718 wall specimens were sectioned from 16 distinct geometric feature build plates constructed on 15 different L-PBF machines. The thin …