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2023

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Articles 6631 - 6660 of 9778

Full-Text Articles in Engineering

Novel Effects Of Grain Size And Ion Implantation On Grain Boundary Segregation In Ion Irradiated Austenitic Steel, Andrew K. Hoffman, Yongfeng Zhang, Maalavan Arivu, Li He, Kumar Sridharan, Yaqiao Wu, Rinat K. Islamgaliev, Ruslan Z. Valiev, Haiming Wen Mar 2023

Novel Effects Of Grain Size And Ion Implantation On Grain Boundary Segregation In Ion Irradiated Austenitic Steel, Andrew K. Hoffman, Yongfeng Zhang, Maalavan Arivu, Li He, Kumar Sridharan, Yaqiao Wu, Rinat K. Islamgaliev, Ruslan Z. Valiev, Haiming Wen

Materials Science and Engineering Faculty Research & Creative Works

Nuclear Reactor Environments Are Extreme in Nature Due to the Combination of Exposure to Corrosive Coolant, Mechanical Stresses, and Neutron Irradiation Damage. This Combination of Environments Can Lead to Irradiation Induced/assisted Precipitation, Segregation, and Embrittlement Coupled with Enhanced Creep and Stress Corrosion Cracking. While Nanostructured Materials Are of Interest in a Variety of Applications Due to their Unique Properties Including High Mechanical Strength, for Nuclear Applications Nanostructured Materials Have the Added Benefit of Irradiation Resistance Due to the High-Volume Density of Sinks for Irradiation-Induced Defects. in This Study, We Show Unique Radiation-Induced Segregation (RIS) Behavior in Nanocrystalline 304 Stainless Steel …

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Garden Improvements For "The Ranch", Ayden J. Cole Mar 2023

Garden Improvements For "The Ranch", Ayden J. Cole

Construction Management

The Ranch spans over ten-and-a-half acres and provides employment opportunities for individuals with disabilities. The core focus of The Ranch is cultivating small crops and raising livestock, which are tended to and harvested by individuals with disabilities. The ultimate aim is to provide them with hands-on experience of working on a farm and how to take care of livestock and grow food. However, the existing property of The Ranch was not exactly what they wanted for their students' learning environment. The existing area where the crops were being grown was not fenced in so critters were getting into the garden …

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The Perceptions And Effects Of Nutrition On Worker Health And Productivity In Construction, Matthew Scott Howell Mar 2023

The Perceptions And Effects Of Nutrition On Worker Health And Productivity In Construction, Matthew Scott Howell

Construction Management

Construction workers often have poor dietary habits due to poor nutrition education, lack of nutritious food options, and social stigma. These habits often lead to health problems like obesity, diabetes, and heart disease which can decrease productivity and put workers at risk of on-site injury. This preliminary study examines how nutrition impacts worker safety and productivity. A survey was distributed to six students involved in construction work for Cal Poly’s Residential Construction course. This survey identified their eating habits and inhibitors for healthy eating. Two meals, one with high nutritional value and one with low nutritional value, were given to …

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New Bike Path On Highland Drive, Christian T. Pedersen Mar 2023

New Bike Path On Highland Drive, Christian T. Pedersen

Construction Management

The purpose of the following paper is to provide a breakdown of the preconstruction and construction processes for a new bike path to be built on Highland Drive. Studies about the selected construction method and materials needed to complete the project are included. Soil-cement will be at the forefront as it offers the cheapest and most efficient way for the proposed new path to be constructed. The explanation for why soil-cement was chosen along with the various other ways in which it can be used are included. One concern the paper will address is the fact that the current bike …

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Feasibility Of Funding Construction-Related Projects With Cryptocurrencies, Farbod Pourdehmobed Mar 2023

Feasibility Of Funding Construction-Related Projects With Cryptocurrencies, Farbod Pourdehmobed

Construction Management

The current method of acquiring funds for construction projects consists of loans and/or a board of investors. With the emergence of the cryptocurrency industry in the past five to ten years, an influx of cash has been inserted into the market and is simply being held captive by government regulations. With development and construction being an attractive investment for most anyone, these "crypto billionaires" are insistent on financing possible projects. The issue lies within the construction industry and the possibly outdated financial system and whether it is capable of adhering to certain requirements that come with the usage of crypto …

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Parental And Family Leave In The California Construction Industry, Hailee Malins Mar 2023

Parental And Family Leave In The California Construction Industry, Hailee Malins

Construction Management

Struggles between work life balance often result in lower levels of job and life satisfaction, and higher rates of inefficiency and employee turnover, with varying impact on employees based on seniority, gender and parenthood. Policies such as paid parental leave have shown positive effects on work life balance, but there is a lack of information on leave policies within the American construction industry. Focusing on California, this research aimed to determine employee's understanding, use and acceptance of these leave policies. Using a survey, we gain a better understanding of these goals. Rates of confidence in knowledge of paternal and family …

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Building Artificial Reefs From Recycled Construction Materials: A Feasibility Study, Nicholas H. Lew Mar 2023

Building Artificial Reefs From Recycled Construction Materials: A Feasibility Study, Nicholas H. Lew

Construction Management

Naturally occurring reefs are some of the world’s most biologically diverse ecosystems formed by jagged rocks tucked slightly below sea level. In recent years global warming began to pose a major threat to many reef habitats. Most relevant is the increase in surface seawater temperatures that cause coral to bleach, taking away major food sources for larger marine species. Researchers have combated this by deploying artificial reefs in substitution for naturally formed limestone rock formations in order to promote the expansion of coastal habitats. This project specifically aims to utilize construction waste towards the production of artificial reefs, effectively upcycling …

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Developments In Construction Insurance And Their Effects On General Contractors, Luke Z. Martin Mar 2023

Developments In Construction Insurance And Their Effects On General Contractors, Luke Z. Martin

Construction Management

Before a construction project can begin, insurance must be purchased by each involved construction player to ensure the financial and physical health of the project and those working to complete it. The necessity of construction insurance on every project has turned it into a behemoth of a market sector, one that significantly affects the construction industry as well as a plethora of others. Although many are unaware, developments and shifts in construction insurance deeply affect the well-being of the public, from the roads they drive on to the buildings they live and work in. This research piece will delve into …

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Cal Poly Construction Management 2022 Summer Bootcamp Team Service Project, Chris Montero Mar 2023

Cal Poly Construction Management 2022 Summer Bootcamp Team Service Project, Chris Montero

Construction Management

This paper describes the project logistics and pre-construction planning of the 2022 Cal Poly Construction Management Summer Bootcamp service-learning project, including a plan, schedule, and estimate of materials. The service-learning project will be a wooden park bench for the San Luis Obispo Botanical Gardens. Four teams of six students each will be provided drawings and, throughout the week-long summer camp, each team will have nine hours and thirty minutes to interpret the plans, cut the materials, and build one bench. The first day will consist of a one-hour project introduction that focuses on the fundamentals of plan reading and preparation …

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Las Vegas Commercial Contractors' Mitigation Techniques For Inflationary Impacts, Kannen I. Caldwell Mar 2023

Las Vegas Commercial Contractors' Mitigation Techniques For Inflationary Impacts, Kannen I. Caldwell

Construction Management

Recent rises in inflation have impacted global business. The construction industry in particular has experienced a decrease in already slim margins due to a plethora of factors. Employers have had difficulty affording increased labor rates to accommodate higher costs of living, ultimately leading to a labor shortage in many areas. Supply chain issues are a product of this labor shortage, but also a myriad of other inflation related issues like the price of gas and global trade agreements. This has led to dramatically increased lead times and has posed major supply chain management issues for project management teams. Construction professionals, …

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Anisotropic Thermal Expansion In High-Entropy Multicomponent Alb2-Type Diboride Solid Solutions, Frédéric Monteverde, Mattia Gaboardi, Federico Saraga, Lun Feng, William Fahrenholtz, Gregory Hilmas Mar 2023

Anisotropic Thermal Expansion In High-Entropy Multicomponent Alb2-Type Diboride Solid Solutions, Frédéric Monteverde, Mattia Gaboardi, Federico Saraga, Lun Feng, William Fahrenholtz, Gregory Hilmas

Materials Science and Engineering Faculty Research & Creative Works

High-entropy (HE) ultra-high temperature ceramics have the chance to pave the way for future applications propelling technology advantages in the fields of energy conversion and extreme environmental shielding. Among others, HE diborides stand out owing to their intrinsic anisotropic layered structure and ability to withstand ultra-high temperatures. Herein, we employed in-situ high-resolution synchrotron diffraction over a plethora of multicomponent compositions, with four to seven transition metals, with the intent of understanding the thermal lattice expansion following different composition or synthesis process. As a result, we were able to control the average thermal expansion (TE) from 1.3 x 10−6 to …

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Particle Migration In Large Cross-Section Ceramic On-Demand Extrusion Components, Austin J. Martin, Wenbin Li, Jeremy Lee Watts, Gregory E. Hilmas, Ming-Chuan Leu, Tieshu Huang Mar 2023

Particle Migration In Large Cross-Section Ceramic On-Demand Extrusion Components, Austin J. Martin, Wenbin Li, Jeremy Lee Watts, Gregory E. Hilmas, Ming-Chuan Leu, Tieshu Huang

Materials Science and Engineering Faculty Research & Creative Works

Ceramic On-Demand Extrusion (CODE) is a direct ink writing process which allows for the creation of near theoretically dense ceramic components with large cross-sections due to oil-assisted drying. Yttria-stabilized zirconia (YSZ) colloidal pastes (∼d50 ≲ 1 µm) were used in CODE to produce dense (multi-road infill and ≳ 98% relative density), large continuous volume (> 1 cm3), and high fidelity (nozzle diameters ≲ 1 mm) structural ceramic components. However, many of these printed components underwent significant particle migration after forming. The reason for this particle migration defect was investigated using the coffee-ring effect for dilute solutions and rheological methods for …

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Growing Grounds Farm, Santa Maria - Greenhouse Planter Bench Tables, Joseph Miller Mar 2023

Growing Grounds Farm, Santa Maria - Greenhouse Planter Bench Tables, Joseph Miller

Construction Management

This paper covers the planning, fundraising, design, construction, and installation associated with building the Growing Grounds Farm of Santa Maria greenhouse planter bench tables. Growing Grounds prides itself on nourishing the local community through a combination of horticulture therapy, and vocational training for individuals with severe and persistent mental illness. The farm offers various opportunities for socialization and interaction with coworkers and customers. After meeting with the farm managers, Anna Wiens and Keith Bartlett, it was clear that this project was of the highest priority. Upon agreement of the project, the farm managers and I determined the future vision and …

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Urban Densification At Twin Creeks Apartments: High-Density Living With Low-Density Luxuries, Ryan Griswold Mar 2023

Urban Densification At Twin Creeks Apartments: High-Density Living With Low-Density Luxuries, Ryan Griswold

Construction Management

Urban sprawl is characterized by the rapid growth of the extent of cities and towns. In the United States, urban sprawl is greatly influenced by housing density. In the past half-century, developers have favored constructing and consumers have preferred living in neighborhoods of detached, single-family homes. This is because low-density living provides more housing services, or additional benefits, than most high-density developments, such as apartments and townhomes. Residents of low-density living often have more privacy, outdoor space, interior natural light, and many other benefits over residents of higher-density developments. However, Twin Creeks Apartments, located in San Luis Obispo, California, is …

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Decomposition Of The Skin-Friction Coefficient Of Compressible Boundary Layers, Dongdong Xu, Pierre Ricco, Lian Duan Mar 2023

Decomposition Of The Skin-Friction Coefficient Of Compressible Boundary Layers, Dongdong Xu, Pierre Ricco, Lian Duan

Mechanical and Aerospace Engineering Faculty Research & Creative Works

We derive an integral formula for the skin-friction coefficient of compressible boundary layers by extending the formula of Elnahhas and Johnson ["On the enhancement of boundary layer skin friction by turbulence: An angular momentum approach, "J. Fluid Mech. 940, A36 (2022)] for incompressible boundary layers. The skin-friction coefficient is decomposed into the sum of the contributions of the laminar coefficient, the change of the dynamic viscosity with the temperature, the Favre-Reynolds stresses, and the mean flow. This decomposition is applied to numerical data for laminar and turbulent boundary layers, and the role of each term on the wall-shear stress is …

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Future Of Augmented And Virtual Reality In Construction, Cameron Ghoddoucy Mar 2023

Future Of Augmented And Virtual Reality In Construction, Cameron Ghoddoucy

Construction Management

A series of virtual design contractors were interviewed regarding the future involvement of augmented and virtual reality software integration with construction processes. Within the construction industry, VDC specialists rely on Building Information Modeling (BIM) and Computer Aided Design (CAD) to create digital models that can be used to analyze the design of a building from all points of view. The interviewees responded to questions about software implementation advantages, and related user experiences. Six interviews were conducted, amongst three industry leading companies. Their assumptions of future AR and VR usage in construction were based on learned knowledge and prior field exploration. …

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Special Section On Local And Distributed Electricity Markets, Rui Bo, Linquan Bai, Antonio J. Conejo, Jianzhong Wu, Tao Jiang, Fei Ding, Babak Enayati Mar 2023

Special Section On Local And Distributed Electricity Markets, Rui Bo, Linquan Bai, Antonio J. Conejo, Jianzhong Wu, Tao Jiang, Fei Ding, Babak Enayati

Electrical and Computer Engineering Faculty Research & Creative Works

Driven by the Goals of Clean Energy and Zero Carbon Emissions, the Power Industry is Undergoing Significant Transformations. the Rapid Growth of Diverse Distributed Energy Resources (DERs) at Grid Edge Such as Rooftop Photovoltaics (PVs) and Electric Vehicles is Transforming the Traditional Centralized Power Grid Management to a Decentralized, Bottom-Up, and Localized Control Paradigm. Establishing Local and Distribution-Level Electricity Markets Provides an Effective Solution to Managing Large Amounts of Small-Scale DERs. New Regulations Such as the Recent FERC Order 2222 in the U.S. Open the Door to DERs in the Wholesale Markets. through Coordinating the Local and Distribution-Level Markets with …

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Description Of Reaction And Vibrational Energetics Of Co2-Nh3interaction Using Quantum Computing Algorithms, Manh Tien Nguyen, Yueh-Lin Lee, Dominic Alfonso, Qing Shao, Yuhua Duan Mar 2023

Description Of Reaction And Vibrational Energetics Of Co2-Nh3interaction Using Quantum Computing Algorithms, Manh Tien Nguyen, Yueh-Lin Lee, Dominic Alfonso, Qing Shao, Yuhua Duan

Markey Cancer Center Faculty Publications

CO2 capture is critical to solving global warming. Amine-based solvents are extensively used to chemically absorb CO2. Thus, it is crucial to study the chemical absorption of CO2 by amine-based solvents to better understand and optimize CO2 capture processes. Here, we use quantum computing algorithms to quantify molecular vibrational energies and reaction pathways between CO2 and a simplified amine-based solvent model—NH3. Molecular vibrational properties are important to understanding kinetics of reactions. However, the molecule size correlates with the strength of anharmonicity effect on vibrational properties, which can be challenging to address using classical computing. Quantum computing can help enhance molecular …

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The Effect Of Relative Humidity On Eddy Covariance Latent Heat Flux Measurements And Its Implication For Partitioning Into Transpiration And Evaporation, Weijie Zhang, Martin Jung, Mirco Migliavacca, Rafael Poyatos, Diego G. Miralles, Tarek S. El-Madany, Marta Galvagno, Arnaud Carrara, Nicola Arriga, Andreas Ibrom, Ivan Mammarella, Dario Papale, Jamie R. Cleverly, Michael Liddell, Georg Wohlfahrt, Christian Markwitz, Matthias Mauder, Eugenie Paul-Limoges, Marius Schmidt, Sebastian Wolf, Christian Brümmer, M. Altaf Arain, Silvano Fares, Tomomichi Kato, Jonas Ardö, Walter Oechel, Chad Hanson, Mika Korkiakoski, Sébastien Biraud, Rainer Steinbrecher, Dave Billesbach, Leonardo Montagnani, William Woodgate, Changliang Shao, Nuno Carvalhais, Markus Reichstein, Jacob A. Nelson Mar 2023

The Effect Of Relative Humidity On Eddy Covariance Latent Heat Flux Measurements And Its Implication For Partitioning Into Transpiration And Evaporation, Weijie Zhang, Martin Jung, Mirco Migliavacca, Rafael Poyatos, Diego G. Miralles, Tarek S. El-Madany, Marta Galvagno, Arnaud Carrara, Nicola Arriga, Andreas Ibrom, Ivan Mammarella, Dario Papale, Jamie R. Cleverly, Michael Liddell, Georg Wohlfahrt, Christian Markwitz, Matthias Mauder, Eugenie Paul-Limoges, Marius Schmidt, Sebastian Wolf, Christian Brümmer, M. Altaf Arain, Silvano Fares, Tomomichi Kato, Jonas Ardö, Walter Oechel, Chad Hanson, Mika Korkiakoski, Sébastien Biraud, Rainer Steinbrecher, Dave Billesbach, Leonardo Montagnani, William Woodgate, Changliang Shao, Nuno Carvalhais, Markus Reichstein, Jacob A. Nelson

Department of Agricultural and Biological Systems Engineering: Faculty Publications

While the eddy covariance (EC) technique is a well-established method for measuring water fluxes (i.e., evaporation or 'evapotranspiration’, ET), the measurement is susceptible to many uncertainties. One such issue is the potential underestimation of ET when relative humidity (RH) is high (>70%), due to low-pass filtering with some EC systems. Yet, this underestimation for different types of EC systems (e.g. open-path or closed-path sensors) has not been characterized for synthesis datasets such as the widely used FLUXNET2015 dataset. Here, we assess the RH-associated underestimation of latent heat fluxes (LE, or ET) from different EC systems for 163 sites in …

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Effects Of Calibration Errors On Dropped-Channel Polarimetric Synthetic Aperture Radar, Jacob C. Morrison Mar 2023

Effects Of Calibration Errors On Dropped-Channel Polarimetric Synthetic Aperture Radar, Jacob C. Morrison

Theses and Dissertations

Compressed Sensing (CS) is a mathematical technique that can be applied to sparse data sets to allow for sub-Nyquist sampling. DCPCS is a CS technique that recovers the signal from unmeasured polarisation channels due to antenna crosstalk coupling the information onto the remaining channels. DCPCS reduces data storage/transmission and receiver hardware requirements. This thesis examines the robustness of DCPCS to calibration errors on the antenna crosstalk matrix. Although the antenna design problem is relaxed to a large region of acceptable crosstalk values, very accurate calibration may be required in a monostatic radar. This thesis also looks at the importance of …

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Long-Term Asset Prioritization To Support District Planning, Melissa R. Sallberg Mar 2023

Long-Term Asset Prioritization To Support District Planning, Melissa R. Sallberg

Theses and Dissertations

The United States Air Force (USAF) relies on its installations to project military power across the globe. However, due to the deferred infrastructure maintenance and recapitalization backlog of $33 billion as of 2019 (Wilson & Goldfein, 2019), it is more critical than ever for base-level community planners to focus their attention to the projects that will achieve each installation’s long-term goals. The recent incorporation of asset management principles into the USAF District Planning Process allows a unique opportunity to improve the existing scoring model for a holistic look at what matters to enterprise leaders and community planners making the plans …

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Sea Level Rise Impacts On Wastewater Treatment Plants And Their Social Vulnerability Differences, David S. P. Robinson Mar 2023

Sea Level Rise Impacts On Wastewater Treatment Plants And Their Social Vulnerability Differences, David S. P. Robinson

Theses and Dissertations

Many of the United States’ major cities that have a high population are located along the coast. The number of people residing in low elevation coastal areas, be-low 10 meters, is increasing. Coastal areas may be affected by various short- and long-term climate hazards, such as sea level rise (SLR). Climate change induced SLR will threaten residents and infrastructure in low-lying coastal areas. A household’s capacity to respond to hazards is highly dependent on its socio-demographic situation which determines its social vulnerability. Wastewater treatment facilities area particularly critical piece of infrastructure often located in low-lying areas due to gravity fed …

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Validation Of Digital System Models, James R. Winton Mar 2023

Validation Of Digital System Models, James R. Winton

Theses and Dissertations

The Department of Defense is undergoing a Digital Transformation driven by Digital Engineering and Model-Based Systems Engineering. Document-based processes are being replaced by digital artifacts, pedigreed data, and an Authoritative Source of Truth for a system across its life cycle. As traditional Design-Build-Test transitions to a Model-Analyze-Build methodology, digital models will proliferate throughout the enterprise and require novel validation processes earlier in the development timeline. A new definition for digital system model validation is proposed to address the identified shortcomings in existing guidance. The proposed validation framework leverages the Systems Modeling Language, use cases, requirements, test cases, and a custom …

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Inducing Sparsity Within High-Dimensional Remote Sensing Modalities For Lightning Prediction, Grace E. Metzgar Mar 2023

Inducing Sparsity Within High-Dimensional Remote Sensing Modalities For Lightning Prediction, Grace E. Metzgar

Theses and Dissertations

The uncertainty of lightning constantly threatens many weather-sensitive fields where the slightest presence of lightning can endanger valuable personnel and assets. The consequences of delaying operations have incited the research of methods that can accurately predict the location of future lightning strikes from the current weather conditions. High-dimensional remote sensing modalities contain information capable of detecting significant patterns and intensities within storms that could indicate the presence of lightning. This thesis induces sparsity into convolutional neural networks (CNNs) and remote sensing modalities through a combination of regularization and tensor decomposition techniques to call attention to sparse features that are most …

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The Aerial Refueling Asset Basing And Assignment Problem, Camryn E. Deames Mar 2023

The Aerial Refueling Asset Basing And Assignment Problem, Camryn E. Deames

Theses and Dissertations

With growing tensions in the European theatre and Indo-Pacific theatre, the constraints of aerial refueling impede the missions of Air Mobility Command and USTRANSCOM in their execution of both the National Security Strategy and National Defense Strategy. Introducing and integrating semi-autonomous aerial refueling aircraft is a logical next step due to advantages in endurance, survivability, runway requirements, and fuel offloading capacity. This research frames the Aerial Refueling Asset Basing and Assignment Problem with two model approaches: a baseline model and a fuel shuttle concept model. Whereas the former model considers instances with only manned refuelers or only semi-autonomous refuelers, the …

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Automated Registration Of Titanium Metal Imaging Of Aircraft Components Using Deep Learning Techniques, Nathan A. Johnston Mar 2023

Automated Registration Of Titanium Metal Imaging Of Aircraft Components Using Deep Learning Techniques, Nathan A. Johnston

Theses and Dissertations

Studies have shown a connection between early catastrophic engine failures with microtexture regions (MTRs) of a specific size and orientation on the titanium metal engine components. The MTRs can be identified through the use of Electron Backscatter Diffraction (EBSD) however doing so is costly and requires destruction of the metal component being tested. A new methodology of characterizing MTRs is needed to properly evaluate the reliability of engine components on live aircraft. The Air Force Research Lab Materials Directorate (AFRL/RX) proposed a solution of supplementing EBSD with two non-destructive modalities, Eddy Current Testing (ECT) and Scanning Acoustic Microscopy (SAM). Doing …

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Debris Survivability Study For Mega-Constellation Architectures, Joseph C. Canoy Mar 2023

Debris Survivability Study For Mega-Constellation Architectures, Joseph C. Canoy

Theses and Dissertations

The analysis for the overall theoretical debris survivabilty of mega-constellation architectures, with an emphasis on space-based ballistic missile defense constellation (SB-BMD), is explored via three extensive different Monte Carlo simulations: preliminary analysis of low Earth Orbit (LEO) mega-constellation survivabilty following a fragmentation event within the constellation, analysis of LEO mega-constellation survivability with a fragmentation event occurring on a satellite performing a maneuver to insert itself within the constellation, and the analysis of LEO mega-constellation survivabilty after a fragmentation event resulting from the destruction of a missile. The LEO mega-constellations represent the SB-BMD constellation. The first two analysis sections will include …

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Investigation Of Hypersonic Near-Wake Relaminarization Over A 7 Degree Half-Angle Cone, Jesse L. Roberts Mar 2023

Investigation Of Hypersonic Near-Wake Relaminarization Over A 7 Degree Half-Angle Cone, Jesse L. Roberts

Theses and Dissertations

To investigate the potential for relaminarization in the near-wake of a 7-degree half-angle cone, a series of hypersonic wake experiments were conducted in the Air Force Research Laboratory Mach 6.1 Ludwieg tube. Relaminarization is a spatial phenomenon that occurs when a turbulent flow reverts to a laminar-like state at a downstream location, where turbulent fluctuations negligibly contribute to average flow properties. Although relaminarization has been documented in subsonic and supersonic flows, the current body of knowledge related to the occurrence of, and mechanisms that drive, relaminarization at hypersonic speeds is sparse. Measurements were obtained across a range of freestream unit …

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Detonation Confinement In A Second-Generation Radial Rotating Engine, John T. Ursino Mar 2023

Detonation Confinement In A Second-Generation Radial Rotating Engine, John T. Ursino

Theses and Dissertations

In recent years, Rotating Detonation Engines (RDEs) have been coupled with turbomachinery to harness the benefits of detonative combustion. A novel type of RDE, referred to as the disk or Radial RDE (RRDE), has been developed in pursuit of length and weight savings compared to a traditional annular flow RDE. This design includes a disk-shaped device within which reactants flow from the outer radius, detonate, and exit the inner radius. In this paper several modifications have been made to a previously tested RRDE to address issues that arose with the original design. The combustion chamber diameter has been increased to …

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Development Of Novel Turbomachinery Manufacturing Methods, Timothy P. Winkler Mar 2023

Development Of Novel Turbomachinery Manufacturing Methods, Timothy P. Winkler

Theses and Dissertations

Compact turbine engines are of increasing interest as a means of propulsion for small, lightweight, low cost, unmanned aerial systems. This study looks to leverage advancements in novel manufacturing technology to produce turbomachinery components while simultaneously reducing costs and manufacturing time. To determine the feasibility of drop-in replacements for stock components this study focused on several research areas. This included materials research on both polymer-reinforced and ceramic materials, specimen tensile testing to determine temperature-dependent material properties, finite element analysis of multiple candidate materials, design and fabrication of a spin test rig, and physical spin testing of manufactured components to predict …

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