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Full-Text Articles in Engineering

On-Chip Nanoscale Plasmonic Optical Modulators, Abdalrahman Mohamed Nader Abdelhamid Jun 2021

On-Chip Nanoscale Plasmonic Optical Modulators, Abdalrahman Mohamed Nader Abdelhamid

Theses and Dissertations

In this thesis work, techniques for downsizing Optical modulators to nanoscale for the purpose of utilization in on chip communication and sensing applications are explored. Nanoscale optical interconnects can solve the electronics speed limiting transmission lines, in addition to decrease the electronic chips heat dissipation. A major obstacle in the path of achieving this goal is to build optical modulators, which transforms data from the electrical form to the optical form, in a size comparable to the size of the electronics components, while also having low insertion loss, high extinction ratio and bandwidth. Also, lap-on-chip applications used for fast diagnostics ...


Stock Market Manipulation Detection Using Continuous Wavelet Transform & Machine Learning Classification, Sarah Youssef Jun 2021

Stock Market Manipulation Detection Using Continuous Wavelet Transform & Machine Learning Classification, Sarah Youssef

Theses and Dissertations

Stock market manipulation detection is important for both investors and regulators. Being able to detect stock manipulation and preventing it gives investors the confidence in the market fairness and integrity. It also helps maintaining liquidity of the stocks and market efficiency. Implementing data mining algorithms in manipulation detection is a relatively recent technique but in the past few years there has been an increasing interest in it's applications in this domain. The benefit of monitoring manipulative trade behavior is that it can be implemented on live feed of stock data, which saves a lot of time in detecting stock ...


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 ...


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 ...


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 ...


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 ...


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 ...


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 ...


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 ...


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 ...


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 ...


Numerical Modeling Of The Fiber Deposition Flow In Extrusion-Based 3d Bioprinting, Dhanvanth Jaya Talluri Apr 2021

Numerical Modeling Of The Fiber Deposition Flow In Extrusion-Based 3d Bioprinting, Dhanvanth Jaya Talluri

Theses and Dissertations

Extrusion bioprinting involves the deposition of bioinks in a layer-wise fashion to build 3D structures that mimic natural living systems' behavior in tissue engineering. Hydrogels are the most common bioinks, in which their viscosity properties are dependent on the shear-rate, such as Non-Newtonian fluids. Numerical simulation of extrusion bioprinting may help study the flow properties of hydrogels and designing improved bioinks. In this thesis, the instability caused by the shear-thinning or -thickening parameter during extrusion is numerically compared with the theoretical estimations. The process of fiber deposition of hydrogels onto a substrate through the single and coaxial nozzle is done ...


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 ...


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 ...


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 ...


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 ...


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 ...


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 ...


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 ...


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 ...


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 ...


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 ...


Optimal Defense Of High Value Airborne Assets, Isaac E. Weintraub Mar 2021

Optimal Defense Of High Value Airborne Assets, Isaac E. Weintraub

Theses and Dissertations

Optimal control theory and differential game theory is applied to the study of the defense of high value airborne assets, particularly in the case of a single threat such as an adversarial aircraft or missile. Rather than utilizing onboard defenses of the high value airborne asset, defense is proposed using a teamed unmanned combat air vehicle. The common scenario throughout this dissertation involves the defense of a high value airborne asset (evader) teamed with an unmanned combat vehicle (defender) against a single threat (pursuer). The unmanned combat air vehicle (defender), provides defense in one of two ways: kinetic or directed ...


Latency Optimization In Smart Meter Networks, Amr Kassab Feb 2021

Latency Optimization In Smart Meter Networks, Amr Kassab

Theses and Dissertations

In this thesis, we consider the problem of smart meter networks with data collection to a central point within acceptable delay and least consumed energy. In smart metering applications, transferring and collecting data within delay constraints is crucial. IoT devices are usually resource-constrained and need reliable and energy-efficient routing protocol. Furthermore, meters deployed in lossy networks often lead to packet loss and congestion. In smart grid communication, low latency and low energy consumption are usually the main system targets. Considering these constraints, we propose an enhancement in RPL to ensure link reliability and low latency. The proposed new additive composite ...


Establishing A Mechanistic Link Between Disturbed Flow And Aneurysm Formation In A 3d Cerebral Bifurcation Model, Nesrine Bouhrira Feb 2021

Establishing A Mechanistic Link Between Disturbed Flow And Aneurysm Formation In A 3d Cerebral Bifurcation Model, Nesrine Bouhrira

Theses and Dissertations

The effect of disturbed flow profiles on the endothelium have been studied extensively in systemic vasculature, but less is known about the response of the blood-brain barrier (BBB) to these flow regimes. Here we investigate the effect of steady and pulsatile disturbed flow on the integrity of the BBB using a three-dimensional, perfusable bifurcation model consisting of a co-culture of endothelial cells with mural and glial cells. Experimental flow patterns predicted by computational fluid dynamics mimic in vivo flow regimes, specifically the presence of a recirculation zone immediately downstream of the bifurcation reveal periodic changes in the instantaneous shear stress ...


Discrete Element Modeling Of Hydrogel Extrusion, Rohit Boddu Feb 2021

Discrete Element Modeling Of Hydrogel Extrusion, Rohit Boddu

Theses and Dissertations

Hydrogels are widely used in extrusion bioprinting as bioinks. Understanding how the hydrogel microstructure affects the bioprinting process aids researchers in predicting the behavior of biological components. Current experimental tools are unable to measure internal forces and microstructure variations during the bioprinting process. In this work, discrete element modeling was used to study the internal interactions and the elastic deformation of the molecular chains within hydrogel networks during the extrusion process. Two-dimensional models of hydrogel extrusions were created in Particle Flow Code (PFC; Itasca Co., Minneapolis, MN). For our model's calibration, hydrogel compression testing was used in which a ...


Investigation Of The Load-Induced Cracking And Rutting Performance Of Specialty Hot Mix Asphalt Overlay Mixtures, Andrae Anthony Francois Feb 2021

Investigation Of The Load-Induced Cracking And Rutting Performance Of Specialty Hot Mix Asphalt Overlay Mixtures, Andrae Anthony Francois

Theses and Dissertations

This study was initiated with the aim of investigating the cracking performance, rutting performance, and cost effectiveness of specialty and composite HMA mixtures utilized in New Jersey to rehabilitate deteriorated rigid pavements. As such, four, plant-produced, specialty HMA overlay mixtures currently used in New Jersey were evaluated in this study. These overlay mixtures included: a dense-graded, 9.5-SP mixture, a gap-graded, 12.5-SMA mixture, a dense graded, 4.75-HPTO mixture, and a uniformly graded, 4.75-BRIC mixture. The 9.5-SP, 12.5-SMA, and 4.75-HPTO mixtures were produced using PG 76-22 binder while the 4.75-BRIC was contained a PG ...


Enhanced Interest Aware Peoplerank For Opportunistic Mobile Social Networks, Yosra Saad Shahin Jan 2021

Enhanced Interest Aware Peoplerank For Opportunistic Mobile Social Networks, Yosra Saad Shahin

Theses and Dissertations

Network infrastructures are being continuously challenged by increased demand, resource-hungry applications, and at times of crisis when people need to work from homes such as the current Covid-19 epidemic situation, where most of the countries applied partial or complete lockdown and most of the people worked from home. Opportunistic Mobile Social Networks (OMSN) prove to be a great candidate to support existing network infrastructures. However, OMSNs have copious challenges comprising frequent disconnections and long delays. we aim to enhance the performance of OMSNs including delivery ratio and delay. We build upon an interest-aware social forwarding algorithm, namely Interest Aware PeopleRank ...


Reinforcement Learning-Based Access Schemes In Cognitive Radio Networks, Ehab Maged Elguindy Jan 2021

Reinforcement Learning-Based Access Schemes In Cognitive Radio Networks, Ehab Maged Elguindy

Theses and Dissertations

In this thesis, we propose different MAC protocols based on three Reinforcement Learning (RL) approaches, namely Q-Learning, Deep Q-Network (DQN), and Deep Deterministic Policy Gradient (DDPG). We exploit the primary user (PU) feedback, in the form of ARQ and CQI bits, to enhance the performance of the secondary user (SU) MAC protocols. Exploiting the PU feedback information can be applied on the top of any SU sensing-based MAC protocol. Our proposed model relies on two main pillars, namely, an infinite-state Partially Observable Markov Decision Process (POMDP) to model the system dynamics besides a queuing-theoretic model for the PU queue; the ...


Multi-Skilled Labor Optimization With Partial Allocation Of Resources, Amira Saleh Jan 2021

Multi-Skilled Labor Optimization With Partial Allocation Of Resources, Amira Saleh

Theses and Dissertations

The current practice of labor allocation in construction schedules assumes single-skilled workforce; meaning that each worker is assumed to be skilled in only one trade. In such practice, at any instance in the project lifecycle, some of the workforce become idle waiting for other labor types to complete their work. Traditionally, companies may relocate idle workers to other projects and return them back to their original project when needed again. This complicates the resource management process and is not often performed successfully, leading to schedule and cost overruns. Alternatively, project managers may keep the idle workforce at their projects because ...