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Articles 1 - 30 of 3141

Full-Text Articles in Engineering

Five Degree-Of-Freedom Property Interpolation Of Arbitrary Grain Boundaries Via Voronoi Fundamental Zone Octonion Framework, Sterling Gregory Baird Apr 2021

Five Degree-Of-Freedom Property Interpolation Of Arbitrary Grain Boundaries Via Voronoi Fundamental Zone Octonion Framework, Sterling Gregory Baird

Theses and Dissertations

In this work we introduce the Voronoi fundamental zone octonion (VFZO) interpolation framework for grain boundary (GB) structure-property models and surrogates. The VFZO framework offers an advantage over other five degree-of-freedom (5DOF) based property interpolation methods because it is constructed as a point set in a Riemannian manifold. This means that directly computed Euclidean distances approximate the original octonion distance with significantly reduced computation runtime (∼7 CPU minutes vs. 153 CPU days for a 50000×50000 pairwise-distance matrix). This increased efficiency facilitates lower interpolation error through the use of significantly more input data. We demonstrate grain boundary energy (GBE) interpolation ...

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Digital Signal Processing Algorithms Implemented On Graphics Processing Units And Software Development For Phased Array Receiver Systems, Mark William Ruzindana Apr 2021

Digital Signal Processing Algorithms Implemented On Graphics Processing Units And Software Development For Phased Array Receiver Systems, Mark William Ruzindana

Theses and Dissertations

Phased array receivers are a set of antenna elements that are capable of forming multiple simultaneous beams over a field of view. In radio astronomy, the study of deep space radio sources, a phased array feed (PAF) is placed at the focus of a large dish telescope that spatially samples the focal plane. PAFs provide an increase in the field of view as compared to the traditional single pixel horn feed, thereby increasing survey speed while maintaining low sensitivity. Phased arrays are also capable of radio frequency interference (RFI) mitigation which is useful in both radio astronomy and wireless communications ...

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Trajectory Generation And Tracking Control For Winged Electric Vertical Takeoff And Landing Aircraft, Jacob B. Willis Apr 2021

Trajectory Generation And Tracking Control For Winged Electric Vertical Takeoff And Landing Aircraft, Jacob B. Willis

Theses and Dissertations

The development of high-energy-density batteries, advanced sensor technologies, and advanced control algorithms for multirotor electric vertical takeoff and landing (eVTOL) unmanned aerial vehicles (UAVs) has led to interest in using these vehicles for a variety of applications including surveillance, package delivery, and even human transportation. In each of these cases, the ideal vehicle is one that can maneuver in congested spaces, but is efficient for traveling long distances. The combination of wings and vectored thrust make winged eVTOLs the obvious choice. However, these aircraft experience a much wider range of flight conditions that makes them challenging to model and control ...

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Compiler-Assisted Software Fault Tolerance For Bare Metal And Rtos Applications On Embedded Platforms, Benjamin James Apr 2021

Compiler-Assisted Software Fault Tolerance For Bare Metal And Rtos Applications On Embedded Platforms, Benjamin James

Theses and Dissertations

In the presence of ionizing particles and other high-energy atomic sources, many electronic and computer systems fail. Single event upsets (SEUs) can be mitigated through hardware and/or software methods. Previous research at BYU has introduced COAST, a compiler-based tool that can automatically add software protection schemes to improve fault coverage of programs. This thesis will expand on the work already done with the COAST project by proving its effectiveness across multiple platforms and benchmarks. The ability to automatically add fault protection to arbitrary user programs will be very valuable for many application designers. The results presented herein show that ...

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Gravel Liquefaction Assessment With The Dynamic Penetration Test At Non-Liquefaction Sites In Valdez, Alaska And L'Aquila, Italy, Nicholas James Linton Apr 2021

Gravel Liquefaction Assessment With The Dynamic Penetration Test At Non-Liquefaction Sites In Valdez, Alaska And L'Aquila, Italy, Nicholas James Linton

Theses and Dissertations

The development of a reliable, and cost-effective in-situ method for characterizing the liquefaction potential of gravelly soils is a considerable challenge for engineers and researchers. The ability to accurately characterize the liquefaction potential of gravelly soils is an important consideration at port facilities and dams for example. The Dynamic Penetration Test (DPT) provides a reliable and cost-effective method for evaluating the liquefaction resistance of gravelly soils. Probabilistic liquefaction triggering curves based on DPT field data have been developed from data collected at 47 sites in China. However, using the DPT-based liquefaction curves for locations outside of the Chengdu plain in ...

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Combined Trajectory, Propulsion And Battery Mass Optimization For Solar-Regenerative High-Altitude Long-Endurance Aircraft, Nathaniel Spencer Gates Apr 2021

Combined Trajectory, Propulsion And Battery Mass Optimization For Solar-Regenerative High-Altitude Long-Endurance Aircraft, Nathaniel Spencer Gates

Theses and Dissertations

This thesis presents the work of two significant projects. In the first project, a suite of benchmark problems for grid energy management are presented which demonstrate several issues characteristic to the dynamic optimization of these systems. These benchmark problems include load following, cogeneration, tri-generation, and energy storage, and each one assumes perfect foresight of the entire time horizon. The Gekko Python package for dynamic optimization is introduced and two different solution methods are discussed and applied to solving these benchmarks. The simultaneous solve mode out-performs the sequential solve mode in each benchmark problem across a wide range of time horizons ...

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Improvements Of Atmospheric Deposition Sampling Procedures And Further Analysis Of Its Impact On Utah Lake, Seth Michael Barrus Apr 2021

Improvements Of Atmospheric Deposition Sampling Procedures And Further Analysis Of Its Impact On Utah Lake, Seth Michael Barrus

Theses and Dissertations

This study focused on Atmospheric Deposition (AD) loading on Utah Lake. Utah Lake is susceptible to Harmful Algal Blooms (HABs) because of its large surface area to volume ratio, proximity to Great Basin dust sources, and various wind patterns from close mountain ranges that blow AD towards the lake. In this study, we continued the collection and analysis of AD samples that started in 2017 and 2018, while reporting additional 2019 and 2020 data. We constructed a sampler on Utah Lake itself, which allowed us to better estimate how AD loads were distributed over the lake. An interpolation assumption was ...

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Fpga-Accelerated Digital Signal Processing For Uav Traffic Control Radar, Kacen Paul Moody Apr 2021

Fpga-Accelerated Digital Signal Processing For Uav Traffic Control Radar, Kacen Paul Moody

Theses and Dissertations

As an extension of previous work done by Luke Newmeyer in his master's thesis \cite{newmeyer2018efficient}, this report presents an improved signal processing chain for efficient, real-time processing of radar data for small-scale UAV traffic control systems. The HDL design described is for a 16-channel, 2-dimensional phased array feed processing chain and includes mean subtraction, windowing, FIR filtering, decimation, spectral estimation via FFT, cross-correlation, and averaging, as well as a significant amount of control and configuration logic. The design runs near the the max allowable memory bus frequency at 300MHz, and using AXI DMA engines can achieve throughput of ...

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Optimization Of Solar-Coal Hybridization For Low Solar Augmentation, Aaron T. Bame Apr 2021

Optimization Of Solar-Coal Hybridization For Low Solar Augmentation, Aaron T. Bame

Theses and Dissertations

One approach to enabling a larger penetration of renewable sources of energy is the implementation of hybrid power plants. This work presents a process to determine the preliminary optimal configuration of a concentrating solar power-coal hybrid power plant with low solar augmentation, and is demonstrated on a coal power plant in Castle Dale, UT. A representative model is developed and validated against published data for a coal power plant of a different configuration than Hunter Unit 3. The simplifications within the representative model include combining multiple feedwater heaters, combining turbines that operate across the same boundary states, and the mass-average ...

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Deploying And Analyzing Air Quality Sensors In Mongolian Gers, Lehi Sttenio Alcantara Apr 2021

Deploying And Analyzing Air Quality Sensors In Mongolian Gers, Lehi Sttenio Alcantara

Theses and Dissertations

The purpose of this research is to develop best practices for deploying air quality sensors in a remote location such as Mongolia. I discussed the architecture and design constraints when collecting remote air quality sensors data, the challenges that emerge while implementing a sensor-based network in a remote location such as Mongolia. The tradeoffs of using different architectures are described. I observed the usage of electrical heaters in modified gers in remote locations and conclude how effective they are in reducing PM2.5 levels by analyzing air quality data and go through the process of cleaning up the data and ...

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Micromechanisms Of Near-Yield Deformation In Bcc Tantalum, Joshua Jr-Syan Tsai Apr 2021

Micromechanisms Of Near-Yield Deformation In Bcc Tantalum, Joshua Jr-Syan Tsai

Theses and Dissertations

New materials, optimized for increased strength, ductility, and other desirable properties, have the potential to improve every aspect of modern living. To achieve these optimums, the necessary technological advancements are impeded mainly by the limits of available material models. Innovations in this field rely on research into the nature of material behavior. While a typical model of material behavior in the region near yield involves the initial linear elastic response, followed by yield and isotropic hardening, this fails to explain various important phenomena that manifest in a range of materials, such as pre-yield nonlinearity, anelasticity, yield point phenomena, hardening stagnation ...

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Characterizing Bacterial Resistance And Microstructure-Related Properties Of Carbon-Infiltrated Carbon Nanotube Surface Coatings With Applications In Medical Devices, Stephanie Renee Morco Apr 2021

Characterizing Bacterial Resistance And Microstructure-Related Properties Of Carbon-Infiltrated Carbon Nanotube Surface Coatings With Applications In Medical Devices, Stephanie Renee Morco

Theses and Dissertations

Carbon-infiltrated carbon nanotube (CICNT) forests are carbon nanotube (CNT) forests infiltrated with pyrolytic carbon to increase durability by becoming a solid material. This material can be tuned to maintain the nanotube geometry of a CNT forest and can also be fabricated on a variety of materials and geometries. Additionally, the present work has indicated that CICNT forests may resist bacterial proliferation and biofilm formation. This phenomenon is not due to the CICNT chemistry; it is presumably due to the CICNT nanostructure morphology. Thus, both silicon and stainless steel substrates were used to investigate CICNT's structural resistance to Methicillin-resistant Staphylococcus ...

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Effect Of Ported Shroud Casing Treatment Modifications On Operational Range And Limits In A Centrifugal Compressor, Alexander A. Newell Apr 2021

Effect Of Ported Shroud Casing Treatment Modifications On Operational Range And Limits In A Centrifugal Compressor, Alexander A. Newell

Theses and Dissertations

The implementation of a ported shroud casing treatment is often used to extend the operating range of a centrifugal compressor. This work utilizes the STAR-CCM+ CFD package to analyze steady-state, single-passage simulations of a centrifugal compressor with and without a ported shroud to better understand how a ported shroud affects compressor flow physics. Verification and validation of simulations were conducted by comparison of results with a time-accurate full-annulus simulation and experimental data. Four different ported shroud revisions were considered and modeled along the full range of their stable operation, with emphasis placed on the flow limits of choke and stall ...

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Introducing The Water Data Explorer Web Application And Python Library: Uniform Means For Data Discovery And Access From Cuahsi And The Wmo Whos Systems, Elkin Giovanni Romero Bustamante Apr 2021

Introducing The Water Data Explorer Web Application And Python Library: Uniform Means For Data Discovery And Access From Cuahsi And The Wmo Whos Systems, Elkin Giovanni Romero Bustamante

Theses and Dissertations

There has been a growing recognition in recent years of the need for a standardized means for sharing water data on the web. One response to this need was the development of the Consortium of Universities for the Advancement of Hydrologic Science (CUAHSI) Hydrologic Information System (HIS) and its accompanying WaterOneFlow and WaterML protocols. To date, the primary means for accessing data shared using these protocols has been limited to the Microsoft Windows HydroDesktop software, the WaterML R package, and the web based CUAHSI HydroClient which serves as an access point to the CUAHSI HIS database. We recognized the need ...

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A Review Of Fitness Tracker Game Elements And A Novel Game Approach For The Design Space, Aatish Neupane Apr 2021

A Review Of Fitness Tracker Game Elements And A Novel Game Approach For The Design Space, Aatish Neupane

Theses and Dissertations

Physical activities like walking have proven health benefits. People are adopting fitness trackers to track physical activity, but they often stop using them after a relatively short time. Many apps and games exist in the app markets that use gamification to tackle this problem of motivation. In this thesis, we examined these existing gamified fitness tracker apps from app markets and looked at the usage of different game elements within these apps. We conducted a systematic review of existing fitness Tracker Apps from Google Play Store and Apple App Store and used a mixed-method approach to identify apps, categorize them ...

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Geoglows Hydroviewer: Open Software-As-A-Service For Localizing Global Hydrologic Forecasts Of The Group On Earth Observations Global Water Sustainability Initiative, Kyler Ralph Ashby Apr 2021

Geoglows Hydroviewer: Open Software-As-A-Service For Localizing Global Hydrologic Forecasts Of The Group On Earth Observations Global Water Sustainability Initiative, Kyler Ralph Ashby

Theses and Dissertations

Earth observation data is increasingly ubiquitous, easily accessible, freely available, and generally usable due to improvements in software, data standards, network infrastructure, and national policies. As a result, greater opportunities arise for using these data in a wider field of application including decision support for local and regional environmental and water resources management efforts. In parts of the world where in situ data are less readily available, global Earth observation data used in such decision support tools can be a boon to underfunded government and private water management agencies. The United Nations Group on Earth Observations Global Water Sustainability initiative ...

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Effects Of Carbon-Infiltrated Carbon Nanotube Growth On The Biocompatibility Of 316l Stainless Steel, Sterling Charles Voss Apr 2021

Effects Of Carbon-Infiltrated Carbon Nanotube Growth On The Biocompatibility Of 316l Stainless Steel, Sterling Charles Voss

Theses and Dissertations

The purpose of this research is to identify the effects of the carbon-infiltrated carbon nanotube (CICNT) growth process on the material properties of 316L stainless steel, particularly those properties which are essential for biocompatibility. Physically altering the micro-topography of a surface can dramatically affect its capacity to support or prevent biofilm growth. Growing CICNTs on biomedical materials is one approach which has demonstrated success at preventing biofilm growth. Unfortunately, the high temperature and carbon-rich gas exposure required for this procedure has proven to have deleterious effects. Rusting has been observed on samples that have been coated with CICNTs and then ...

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Coal Pyrolysis Models For Use In Massively Parallel Oxyfuel-Fired Boiler Simulations, Andrew Perry Richards Mar 2021

Coal Pyrolysis Models For Use In Massively Parallel Oxyfuel-Fired Boiler Simulations, Andrew Perry Richards

Theses and Dissertations

Accurately modeling key aspects of coal combustion allows for the virtual testing and application of new technologies and processes without the need for investments in lab- and pilot-scale facilities, since such facilities may only be used for a few small tests. However, modeling of subprocesses must not only be accurate but computationally efficient. Modeling of coal devolatilization reactions and processes are one of the important parts of large-scale simulations of coal combustion systems. The work presented here details efforts to improve the modeling of coal devolatilization processes in massively-parallel simulations of coal combustors, including: (1) devolatilization rate/yield models, (2 ...

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A New Method And Python Toolkit For General Access To Spatiotemporal N-Dimensional Raster Data, Riley Chad Hales Mar 2021

A New Method And Python Toolkit For General Access To Spatiotemporal N-Dimensional Raster Data, Riley Chad Hales

Theses and Dissertations

Scientific datasets from global-scale scientific models and remote sensing instruments are becoming available at greater spatial and temporal resolutions with shorter lag times. These data are frequently gridded measurements spanning two or three spatial dimensions, the time dimension, and often several data dimensions which vary by the specific dataset. These data are useful in many modeling and analysis applications across the geosciences. Unlike vector spatial datasets, raster spatial datasets lack widely adopted conventions in file formats, data organization, and dissemination mechanisms. Raster datasets are often saved using the Network Common Data Format (NetCDF), Gridded Binary (GRIB), Hierarchical Data Format (HDF ...

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Nonlinear Trajectory Tracking Control For Winged Evtol Uavs, Jacob Willis, Randal W. Beard Mar 2021

Nonlinear Trajectory Tracking Control For Winged Evtol Uavs, Jacob Willis, Randal W. Beard

Faculty Publications

Current control methods for winged eVTOL UAVs consider the vehicle primarily as a fixed-wing aircraft with the addition of vertical thrust used only during takeoff and landing. These methods provide good long-range flight handling but fail to consider the full dynamics of the vehicle for tracking complex trajectories. We present a trajectory tracking controller for the full dynamics of a winged eVTOL UAV in hover, fixed-wing, and partially transitioned flight scenarios. We show that in low- to moderate-speed flight, trajectory tracking can be achieved using a variety of pitch angles. In these conditions, the pitch of the vehicle is a ...

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Molecular Dynamic Simulation Of Protein Devices And The Parameterization Of Azides And Alkynes For Use In Unnatural Amino Acid Models, Addison Kyle Smith Jan 2021

Molecular Dynamic Simulation Of Protein Devices And The Parameterization Of Azides And Alkynes For Use In Unnatural Amino Acid Models, Addison Kyle Smith

Theses and Dissertations

Proteins that have been modified by attaching them to a surface or to a polyethylene glycol (PEG) molecule can see many uses in therapeutics and diagnostics -- these unique proteins are called protein devices. Current techniques can perform these functionalizations at a specific residue on the protein, but what remains is identifying what happens to protein structure when mutated, and where to perform the attachment. Both of these issues can be examined using molecular dynamic (MD) simulations. Currently, simulations of the unnatural amino acid (uAA) mutations necessary for protein device functionalization cannot be executed, and full-protein screens of all possible protein ...

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Molecular Dynamic Simulation Of Protein Devices And The Parameterization Of Azides And Alkynes For Use In Unnatural Amino Acid Models, Addison Kyle Smith Jan 2021

Molecular Dynamic Simulation Of Protein Devices And The Parameterization Of Azides And Alkynes For Use In Unnatural Amino Acid Models, Addison Kyle Smith

Theses and Dissertations

Proteins that have been modified by attaching them to a surface or to a polyethylene glycol (PEG) molecule can see many uses in therapeutics and diagnostics -- these unique proteins are called protein devices. Current techniques can perform these functionalizations at a specific residue on the protein, but what remains is identifying what happens to protein structure when mutated, and where to perform the attachment. Both of these issues can be examined using molecular dynamic (MD) simulations. Currently, simulations of the unnatural amino acid (uAA) mutations necessary for protein device functionalization cannot be executed, and full-protein screens of all possible protein ...

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Effects Of Static And Dynamic Thermal Gradients In Gas Chromatography, Samuel Avila Jan 2021

Effects Of Static And Dynamic Thermal Gradients In Gas Chromatography, Samuel Avila

Theses and Dissertations

Gas chromatography (GC) is an analytical chemistry tool used to determine the chemical composition of a gas sample by separating sample analytes as they travel through a GC column. Recent efforts have been made to understand and control gas chromatography separations with a negative thermal gradient on the column. The present work presents results from thermal gradient GC separations on two GC columns in different configurations (serpentine and radial) in a stainless-steel plate. Methods to fabricate the GC systems capable of isothermal, temperature programmed and thermal gradient separations are presented. Isothermal experimental data from the serpentine column were used to ...

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Deploying And Analyzing Air Quality Sensors In Mongolian Gers, Lehi Alcantara Jan 2021

Deploying And Analyzing Air Quality Sensors In Mongolian Gers, Lehi Alcantara

ScholarsArchive Data

This is work done for a thesis that would be way too long to attach to the thesis document. It contains code, spreadsheets, data.

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Optimization Of Turbine Tilt In A Wind Farm, James Cutler, Andrew P.J. Stanley, Jared J. Thomas, Andrew Ning Jan 2021

Optimization Of Turbine Tilt In A Wind Farm, James Cutler, Andrew P.J. Stanley, Jared J. Thomas, Andrew Ning

Faculty Publications

Wind farm power production is significantly affected by upstream turbines creating wakes of slower wind speeds that overlap the rotor swept areas of downstream turbines. By optimizing the tilt angle of the turbines in a farm, wakes may be deflected away from downstream turbines, increasing the overall energy production. In this study, we optimized the tilt angle of turbines in a wind farm to maximize energy production. We used an analytic wake model modified for gradient-based optimization to consider wake deflection from tilt. We considered optimizing the tilt angle of each turbine assuming that it remained fixed for the lifetime ...

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Reducing Wind Farm Power Variance From Wind Direction Using Wind Farm Layout Optimization, Bertelsen Gagakuma, Andrew P.J. Stanley, Andrew Ning Jan 2021

Reducing Wind Farm Power Variance From Wind Direction Using Wind Farm Layout Optimization, Bertelsen Gagakuma, Andrew P.J. Stanley, Andrew Ning

Faculty Publications

This paper investigates reducing power variance caused by different wind directions by using wind farm layout optimization. The problem was formulated as a multi-objective optimization. The ε−constraint method was used to solve the bi-objective problem in a two-step optimization framework where two sequential optimizations were performed. The first was maximizing the mean wind farm power alone and the second was minimizing the power variance with a constraint on the mean power. The results show that the variance in power estimates can be greatly reduced, by as much as 30%, without sacrificing mean plant power for the different farm sizes ...

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A Comparison Of Aerodynamic Models For Optimizing The Takeoff And Transition Of A Bi-Wing Tailsitter, Ryan Anderson, Jacob Willis, Jacob Johnson, Andrew Ning, Randal Beard Jan 2021

A Comparison Of Aerodynamic Models For Optimizing The Takeoff And Transition Of A Bi-Wing Tailsitter, Ryan Anderson, Jacob Willis, Jacob Johnson, Andrew Ning, Randal Beard

Faculty Publications

Electric vertical takeoff and landing (eVTOL) aircraft take advantage of distributed electric propulsion as well as aerodynamic lifting surfaces to take off vertically and perform long-duration flights. Complex aerodynamic interactions and a hard-to-predict transition maneuver from hover to wing-borne flight are one challenge in their development. To address this, we compare three different interaction models of varying fidelity for optimizing the transition trajectory of a biplane tailsitter. The first model accounts for simplified rotor-on-wing interactions using momentum theory, while the other two account for wing-on-wing interactions using a vortex lattice method and rotor-on-wing aerodynamic interactions using blade element momentum theory ...

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Experimental And Modeling Of Biomass Char Gasification, Ruochen Wu Dec 2020

Experimental And Modeling Of Biomass Char Gasification, Ruochen Wu

Theses and Dissertations

This investigation provides a comprehensive experimental dataset and kinetic model for biomass gasification, over a wide temperature range (1150-1350 °Ï¹) in CO2, H2O and the combination of these two reactant gases over the mole fraction ranges of 0 to 0.5 for H2O and 0 to 0.9 for CO2. The data come from a unique experimental facility that tracks continuous mass loss rates for poplar wood, corn stover and switchgrass over the size range of 6-12.5 mm. In addition, the data include char size, shape, surface and internal temperature and discrete measurements of porosity, total surface area, pore ...

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Root Cause Analysis And Classification Of Single Point Failures In Designs Applying Triple Modular Redundancy In Sram Fpgas, James D. Swift Dec 2020

Root Cause Analysis And Classification Of Single Point Failures In Designs Applying Triple Modular Redundancy In Sram Fpgas, James D. Swift

Theses and Dissertations

Radiation effects encountered in space or aviation environments can affect the configuration bits in Field Programmable Gate Arrays (FPGA) causing errors in FPGA output. One method of increasing FPGA reliability in radiation environments includes adding redundant logic to mask errors and allow time for repair. Despite the redundancy added with triple modular redundancy (TMR) and configuration scrubbing there exist some configuration bits that individually affect multiple TMR domains causing errors in FPGA output. A new tool called DeBit is introduced that identifies hardware resources associated with a single bit failure. This tool identifies a novel failure mode involving global routing ...

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Instructional Case Studies In The Field Of Windfarm Optimization, N. Francesco Baker Dec 2020

Instructional Case Studies In The Field Of Windfarm Optimization, N. Francesco Baker

Theses and Dissertations

Wind farm layout optimization is a multidisciplinary undertaking, requiring students and researchers to integrate many skillsets in order to optimize turbine placement. There is currently a lack of useful benchmarking exercises for participants in the field to compare the efficacy of their methods. This work details the construction and completion of a set of four case studies meant to satisfy this need, with the hope of providing some insight into useful layout optimization approaches. These case studies are intended to also serve as instructive introductory exercises with which newcomers researching wind energy may incrementally practice and increase their abilities.The ...

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