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Full-Text Articles in Engineering

Applying Machine Learning Techniques To Improve Safety And Mobility Of Urban Transportation Systems Using Infrastructure- And Vehicle-Based Sensors, Zubayer Islam Jan 2021

Applying Machine Learning Techniques To Improve Safety And Mobility Of Urban Transportation Systems Using Infrastructure- And Vehicle-Based Sensors, Zubayer Islam

Electronic Theses and Dissertations, 2020-2023

The importance of sensing technologies in the field of transportation is ever increasing. Rapid improvements of cloud computing, Internet of Vehicles (IoV), and intelligent transport system (ITS) enables fast acquisition of sensor data with immediate processing. Machine learning algorithms provide a way to classify or predict outcomes in a selective and timely fashion. High accuracy and increased volatility are the main features of various learning algorithms. In this dissertation, we aim to use infrastructure- and vehicle-based sensors to improve safety and mobility of urban transportation systems. Smartphone sensors were used in the first study to estimate vehicle trajectory using lane …


Reliable And Efficient Cognitive Radio Communications Using Directional Antennas, Hassan Yazdani Jan 2021

Reliable And Efficient Cognitive Radio Communications Using Directional Antennas, Hassan Yazdani

Electronic Theses and Dissertations, 2020-2023

Cognitive Radio (CR) is a promising solution that enhances spectrum utilization by allowing an unlicensed or Secondary User (SU) to access licensed bands in a such way that its imposed interference on a license holder Primary User (PU) is limited, and hence fills the spectrum holes in time and/or frequency domains. Resource allocation, which involves scheduling of available time and transmit power, represents a crucial problem for the performance evaluation of CR systems. In this dissertation, we study the spectral efficiency maximization problem in an opportunistic CR system. Specifically, in the first part of the dissertation, we consider an opportunistic …


A Framework And Model For Managing And Sustaining A Successful Cross Functional Project Operations Team In A Multi-Project Manufacturing Environment In The Aerospace And Defense Industry, Anisulrahman Nizam Jan 2021

A Framework And Model For Managing And Sustaining A Successful Cross Functional Project Operations Team In A Multi-Project Manufacturing Environment In The Aerospace And Defense Industry, Anisulrahman Nizam

Electronic Theses and Dissertations, 2020-2023

Project manufacturing is a production manufacturing mode that develops and produces large and complex systems that is supplemented by project management techniques for planning and execution. Project manufacturing is better understood by examining it along with three other key areas: manufacturing, project management, and team management. Critical success factors for each of these areas have been examined in the literature but have not been examined in a real world setting in the aerospace and defense industry. This research examines the association between perspectives of project teams and senior management on critical success factors along the four identified dimensions of success …


Wind Turbine Main Bearing Fatigue Prognosis With Physics-Informed Machine Learning, Yigit Yucesan Jan 2021

Wind Turbine Main Bearing Fatigue Prognosis With Physics-Informed Machine Learning, Yigit Yucesan

Electronic Theses and Dissertations, 2020-2023

Unexpected main bearing failure on a wind turbine causes unscheduled maintenance and increased operation costs (mainly due to crane, parts, labor, and production loss). Unfortunately, historical data indicates that failure can happen far earlier than the component designed lives (due to manufacturing problems, for example). For the legacy fleet, which composes the majority of the installed basis, fatigue has become a major issue. Although bearing fatigue can be expressed with physics-informed models, they often inherent large uncertainties due to operation and unknown lubricant degradation mechanism. Apart from the unknown physics of failure, additional uncertainties associated with the grease that surrounds …


Econometric Frameworks For Energy Prediction, Naveen Chandra Iraganaboina Jan 2021

Econometric Frameworks For Energy Prediction, Naveen Chandra Iraganaboina

Electronic Theses and Dissertations, 2020-2023

Global warming and associated role of energy consumption across various sectors is a well-researched topic in recent years. Understanding current urban energy consumption patterns will allow us to understand how future energy consumption patterns will evolve. With electrification of vehicles and potentially altering culture of work from home, the energy usage at regional level would see a significant change in the future. The current PhD dissertation contributes to energy consumption analysis of a region by analyzing residential energy consumption, commercial energy consumption and transportation energy use by households. The aggregation of these energy consumption within a region contributes to the …


Signals As Symbols: Applying Normalization Of Deviance To Improve User-Centered Design, Amy Vanschaik Jan 2021

Signals As Symbols: Applying Normalization Of Deviance To Improve User-Centered Design, Amy Vanschaik

Electronic Theses and Dissertations, 2020-2023

Mistakes can happen in the process of designing and developing interactive digital projects. Sometimes these mistakes negatively impact users' perception and trust of digital interfaces. This research applies the concept of normalization of deviance to identify potential missed opportunities in user-centered design data within the context of a website redesign. By doing this I explore how through observing accidental deviant behaviors or processes we can identify ways to improve the usability and user experience of digital environments. I review the concepts of normalized deviant behavior as addressed by Diane Vaughan in the field of engineering and identify a process for …


Assessment Of Work-Related Feelings Among Teachers Within The United States And Jordan, Shahed Obeidat Jan 2021

Assessment Of Work-Related Feelings Among Teachers Within The United States And Jordan, Shahed Obeidat

Electronic Theses and Dissertations, 2020-2023

Human personalities combined with working conditions affect how employees react to different work situations. Personality and work environment have also been shown to affect workers' feelings. Employees' psychological health plays an essential role in their performance and productivity in the workplace, and organizational awareness of work-related feelings has sparked interest in investigating this field of study. Teaching is a stressful job; however, research evaluating discrete states of work-related emotions in teachers remains somewhat limited. This study investigated the effects of job demands on teachers' work-related feelings within middle and high schools in the United States and Jordan. The study results …


Index-Based Approach With Remote Sensing For The Assessment Of Extreme Weather Impact On Watershed Vegetation Dynamics, Kushan Bellanthudawage Jan 2021

Index-Based Approach With Remote Sensing For The Assessment Of Extreme Weather Impact On Watershed Vegetation Dynamics, Kushan Bellanthudawage

Electronic Theses and Dissertations, 2020-2023

Spatial technologies such as satellite remote sensing can be used to identify vegetation dynamics over space and time, which play a critical role in earth observations. Biophysical and biochemical features associated with vegetation cover can then be used to elucidate climate change impact such as floods and droughts on ecosystem that may in turn affect watershed-scale water resources management. Unlike single flood or drought event, intermittent extreme weather events may exert more physiological and biological pressures on the canopy vegetation. This study aims to investigate the climate change impacts on canopy vegetation, which occurred from March 2017 to October 2017 …


Performance Enhancement Of Rf/Microwave Devices Using Filter Synthesis Techniques, Ricardo Lovato Jan 2021

Performance Enhancement Of Rf/Microwave Devices Using Filter Synthesis Techniques, Ricardo Lovato

Electronic Theses and Dissertations, 2020-2023

This dissertation shows that filter synthesis techniques can be used to design and enhance the performance of several discrete components of the RF front-end. Throughout this work, a block diagram of a typical receiver is used to illustrate each component separately. Four main areas are covered: (1) filter/antenna integration, (2) frequency-tunable filter/antenna integration with control of the bandwidth characteristics, (3) antenna arrays designed based on integrated cavity resonators, and (4) novel low-loss phase shifters using band-pass and band-stop filters. The filter/antenna designed using two cavity resonators with a slot antenna in the second cavity. The slot antenna excites two modes …


Identifying The Links Between Mental Frameworks, Context Features, And Driver Attention In Complete Streets Environments, Patricia Tice Jan 2021

Identifying The Links Between Mental Frameworks, Context Features, And Driver Attention In Complete Streets Environments, Patricia Tice

Electronic Theses and Dissertations, 2020-2023

Complete street systems integrate a wide range of users in the same space, with unequal risks and responsibilities. This makes driver attention a critical factor in assuring the safety of vulnerable users. The Conditioned Anticipation of People psychological model of driver attention proposes that drivers reflexively reengage their metacognitive processes when they anticipate visually interacting with the human face or form due to the neurological priority that the brain places on human recognition. To test this model, an eye-tracking tabulation was generated from the SHRP2 Naturalistic Driving Study that measured midsegment percent of time on-task and multitasking behavior for 200 …


Studies On Powder Compaction And Wire Extrusion Of Pure Metals And Metal/Cnt Nano Composites, Qiang Zhou Jan 2021

Studies On Powder Compaction And Wire Extrusion Of Pure Metals And Metal/Cnt Nano Composites, Qiang Zhou

Electronic Theses and Dissertations, 2020-2023

The goal of this dissertation is to fabricate wires made of Cu/CNT and Al/CNT composites with good mechanical strength and super thermal/electrical conductivities using powder compaction and wire extrusion manufacturing processes. Powder compaction was studied using both test and simulation. Cold compaction, hot compaction and vibration assisted (cold) compaction tests were conducted to achieve different density ratios. Hot compaction tests improved about 6% compared with cold compaction under the same compression pressure. Although the relative density ratio does not obviously improve at vibration assisted (cold) compaction, the strength of the specimens made under vibration loading is much better than those …


Distributed Service Restoration In Active Distribution Networks, Nejad Reza Roofegari Jan 2021

Distributed Service Restoration In Active Distribution Networks, Nejad Reza Roofegari

Electronic Theses and Dissertations, 2020-2023

Despite tremendous efforts on increasing power system reliability, outages and blackouts are inevitable. These losses can be greatly reduced by fast and reliable restoration mechanisms. Largescale distribution networks and increasing penetration of distributed energy resources (DERs) make restoration one of the most challenging problems in power systems. The prevailing centralized restoration scheme is costly, limited by information privacy of entities, unreliable due to dependence on central units, and might suffer from single-point failures. In this dissertation, a fully distributed restoration framework based on the alternating direction method of multipliers (ADMM) is proposed to address these challenges. Accordingly, the restoration problem …


An Evaporation Based Micro-Synthetic Jet In Microchannel And Its Applications, Ehsan Sourtiji Jan 2021

An Evaporation Based Micro-Synthetic Jet In Microchannel And Its Applications, Ehsan Sourtiji

Electronic Theses and Dissertations, 2020-2023

An approach to create synthetic jets at micro-scales using periodic bubble growth and collapse was presented and studied over a range of operating frequencies (0.1 to 2.5 Hz) and heating powers (3 to 4.5 Watt). The microfluidic device uses an interfacial layer between vapor and liquid phases which substitutes the requirement for a physical flexible membrane and any other moving parts. The bubble explosion and implosion in the chamber was triggered by periodically powering a micro-heater, which in turn generated the synthetic jet. High-speed camera photography and a microscope were used to capture sequential images of bubble nucleation, growth and …


Mid-Infrared Laser Absorption Spectroscopy And Ignition Delay Time Measurements Of Advanced Renewable Fuels At High Pressure In A Shock Tube, Erik Ninnemann Jan 2021

Mid-Infrared Laser Absorption Spectroscopy And Ignition Delay Time Measurements Of Advanced Renewable Fuels At High Pressure In A Shock Tube, Erik Ninnemann

Electronic Theses and Dissertations, 2020-2023

The United States government has set 2050 as the target for net-zero greenhouse gas emissions due to their increasing levels and the subsequent rise in global temperatures. To meet this target, there has been renewed interest in the combustion of high-energy biofuels that could combat these issues. Thus, the Department of Energy started the Co-Optimization of Fuels and Engines program to find bioderived blendstocks that can harmonize with current and future generation engines to increase power and efficiency, all while reducing overall emissions. As part of this program, it is crucial to understand the combustion of these fuels at the …


Simulating Ejecta Blown Off The Lunar Surface Due To Landing Spacecraft Using The Mercury N-Body Integrator, Isabel Rivera Jan 2021

Simulating Ejecta Blown Off The Lunar Surface Due To Landing Spacecraft Using The Mercury N-Body Integrator, Isabel Rivera

Electronic Theses and Dissertations, 2020-2023

The experiences of the Apollo lunar landings revealed the danger lunar dust can pose to surrounding hardware, outposts, and orbiting spacecraft. Future lunar missions such as the Artemis program will require more information about the trajectories of ejecta blown by landers to protect orbiting spacecraft such as the Lunar Gateway. In this paper, we simulate lunar lander ejecta trajectories using the Mercury N-body integrator. We placed cones of test particles on the Moon at the North Pole, South Pole, and Equator with various ejection speeds and angles. The results show that particles ejected at speeds near the Moon's escape velocity …


Seismic Soil-Structure Interaction Effects In Tall Buildings Considering Nonlinear-Inelastic Behaviors, Jaime Mercado Jan 2021

Seismic Soil-Structure Interaction Effects In Tall Buildings Considering Nonlinear-Inelastic Behaviors, Jaime Mercado

Electronic Theses and Dissertations, 2020-2023

Soil-structure interaction (SSI) effects are relevant for the seismic analysis of tall buildings on shallow foundations since the dynamic behavior of structures is highly affected by the interaction between the superstructure and supporting soils. As part of earthquake-resistant designs of buildings, considering SSI effects in the analysis provides more realistic estimates of its performance during a seismic event, particularly when both the structure and soil undergo large demands that can compromise serviceability. Oversimplifications of structural or soil modeling in the analysis introduces variability and biases in the computed seismic response. The main goal of this dissertation is to investigate the …


Understanding Forearm Muscle Coordination In Children, Miguel Gonzalez Jan 2021

Understanding Forearm Muscle Coordination In Children, Miguel Gonzalez

Electronic Theses and Dissertations, 2020-2023

A combination of surface electromyography (EMG) and pattern recognition algorithms have led to improvements in the functionality of upper limb prosthetics. This method of control relies on user's ability to repeatedly generate consistent muscle contractions. Research in EMG based control of prosthesis has mainly utilized adult subjects who have fully developed neuromuscular control. Little is known about children's ability to generate consistent EMG signals necessary to control artificial limbs with multiple degrees of freedom. To address this gap, two experiments were designed to validate and benchmark an experimental protocol that quantifies the ability to coordinate forearm muscle contractions in able-bodied …


Solidification Cracking In Binary Al-Cu Alloys Additively Manufactured Through Laser Powder Bed Fusion, Keegan Muller Jan 2021

Solidification Cracking In Binary Al-Cu Alloys Additively Manufactured Through Laser Powder Bed Fusion, Keegan Muller

Electronic Theses and Dissertations, 2020-2023

Laser Powder Bed Fusion (LPBF) is an additive manufacturing technique with growing relevance in industry. However, alloys with a high susceptibility to micro-cracking during solidification cannot be feasibly manufactured through LPBF, such as in selected high-strength Al-alloys. The cracking susceptibility (CS) of Al-alloys varies with composition, so modeling CS with respect to composition is crucial in designing compatible alloys for LPBF. In a theoretical modeling of solidification cracking based on the Scheil equation, the relative CS is taken as the maximum value of |dT/d(fs^1/2)| when solidification is near completion. However, experimental observations of the crack density in Al-alloys suggest that …


Optimizing Peer Selection Among Internet Service Providers (Isps), Shahzeb Mustafa Jan 2021

Optimizing Peer Selection Among Internet Service Providers (Isps), Shahzeb Mustafa

Electronic Theses and Dissertations, 2020-2023

Connections among Internet Service Providers (ISPs) form the backbone of the Internet. This enables communications across the globe. ISPs are represented as Autonomous Systems (ASes) in the global Internet and inter-ISP traffic exchange takes place via inter-AS links, which are formed based on inter-ISP connections and agreements. In addition to customer-provider agreements, a crucial type of inter-ISP agreement is peering. ISP administrators use various platforms like AP-NIC and NANOG networking events for establishing new peering connections in accordance with their business and technical needs. Such methods are often inefficient and slow, potentially resulting in missed opportunities or sub-optimal routes. The …


Neural Signatures Of Human Perception Of Effort And Comfort In Isometric Arm Force Exertions By Males, Raul Fernandez Sumano Jan 2021

Neural Signatures Of Human Perception Of Effort And Comfort In Isometric Arm Force Exertions By Males, Raul Fernandez Sumano

Electronic Theses and Dissertations, 2020-2023

Understanding the brain's electrical activity provides objective evidence of different psychophysical phenomena related to manual handling tasks. The primary objective of this research was to assess the neural signatures of human physical efforts and perceived comfort in isometric arm exertions. Two experiments were conducted with male participants (n=20) who applied isometric forces at 1) different levels of exertion and 2) different levels of physical comfort. EEG signals, the rate of perceived exertion (RPE), and the rate of perceived physical comfort (RPC) have been recorded. The results showed statistically significant differences in EEG's power spectral density (PSD) at different brain regions …


Florida Building Code, Energy Conservation, 7th Edition (2020) Vs. 2018 International Energy Conservation Code Residential Stringency Analysis, Florida Solar Energy Center, Jeffrey Sonne Dec 2020

Florida Building Code, Energy Conservation, 7th Edition (2020) Vs. 2018 International Energy Conservation Code Residential Stringency Analysis, Florida Solar Energy Center, Jeffrey Sonne

FSEC Energy Research Center®

This report summarizes the review and evaluation activities carried out to make a determination whether the residential provisions of the 7th Edition (2020) Florida Building Code, Energy Conservation meet or exceed those of the 2018 International Energy Conservation Code (IECC) code.


Market Driven Residential Energy Codes: Comparing Performance In A Changing Technical Environment, Code Official Survey Results, Florida Solar Energy Center, Karen Fenaughty Dec 2020

Market Driven Residential Energy Codes: Comparing Performance In A Changing Technical Environment, Code Official Survey Results, Florida Solar Energy Center, Karen Fenaughty

FSEC Energy Research Center®

The DOE Code Survey conducted for this project was launched on 2/18/2020 and closed 3/20/2020. There were 907 participants responding to at least some portion of the 48 question survey, though some questions received poor attention. Note that the number of responses to each question varies by design and depends on answers to prior questions. Further, multiple answers are sometimes allowed.


Research Experience For Undergraduates During Covid-19, Mustafa Akbas Oct 2020

Research Experience For Undergraduates During Covid-19, Mustafa Akbas

Florida Statewide Symposium: Best Practices in Undergraduate Research

This presentation provides the student team interaction and mentorship experience at Embry-Riddle Aeronautical University’s “National Science Foundation (NSF) Research Experiences for Undergraduates (REU) Site: Cybersecurity Research of Unmanned Aerial Vehicles” from the summer semester of 2020. The Site had been planned for a face-of-face research experience under several mentors for an eight-week period. However, due to Covid-19, the teams had to meet, discuss, present and work online, which was both a challenge and an opportunity. Both students and mentors had lessons from this online experience that they will remember and use in the upcoming years. In this presentation, we present …


Fsec Energy Research Center Highlights 2020, Brochure, Florida Solar Energy Center, Sherri Shields Sep 2020

Fsec Energy Research Center Highlights 2020, Brochure, Florida Solar Energy Center, Sherri Shields

FSEC Energy Research Center®

This 5-page "brochure" provides an overview of capabilities at the FSEC Energy Research Center. As Florida's statewide energy research center, FSEC has a 45-year history of basic and applied research excellence, which has grown in scope to include all aspects of renewable energy, energy storage, electric vehicles, and energy efficiency technologies. FSEC's education and outreach programs have trained thousands of energy practitioners and informed energy consumers. This document was originally created to inform City of Cocoa Council members about FSEC during their external visit to the Center in June 2020, during COVID-19. FSEC Art#: PIO-104


Mimicking Blood Rheology For More Accurate Modeling In Benchtop Research, Lindsey Webb Aug 2020

Mimicking Blood Rheology For More Accurate Modeling In Benchtop Research, Lindsey Webb

The Pegasus Review: UCF Undergraduate Research Journal

Because blood is challenging to use as a working fluid in a laboratory setting due to health and safety concerns, a blood analogue would be useful to perform benchtop experiments. Viscosity is an important fluid property for modeling and experiments, especially because blood is a shear thinning fluid; therefore, it has a decreasing viscosity with higher shear rates. This project seeks to create a blood-mimicking fluid for benchtop laboratory use. Numerous fluids with different combinations of water, glycerin, salt, and xanthan gum (XG) were created to mimic blood viscosity at different hematocrit levels. Four additional solutions were also created from …


Measured Cooling Energy Savings From Reflective Wall Finishes: Evaluation As An Efficiency Measure Across Climates, Florida Solar Energy Center, Danny Parker Aug 2020

Measured Cooling Energy Savings From Reflective Wall Finishes: Evaluation As An Efficiency Measure Across Climates, Florida Solar Energy Center, Danny Parker

FSEC Energy Research Center®

In past research, reflective roofs have shown significant potential to reduce cooling in buildings. However, there have been few empirical evaluations of cooling reductions from changing wall reflectance. In the reported study, several experiments with instrumented scale test buildings are used to provide validation for a detailed simulation analysis across varied North American climates. The simulations establish the potential of reflective walls as an efficiency measure in existing buildings against climate.

This paper was published in the 2020 ACEEE Summer Study on Energy Efficiency in Buildings.


Who's Leading: The Dance Between Mini-Splits And Existing Hvac Systems, Florida Solar Energy Center, Cheryn Metzger Aug 2020

Who's Leading: The Dance Between Mini-Splits And Existing Hvac Systems, Florida Solar Energy Center, Cheryn Metzger

FSEC Energy Research Center®

Recently, many utilities across the U.S. have provided incentives for ductless mini-split heat pumps due to their relatively high efficiencies. However, when these ductless mini-splits are installed in existing homes, utilities and researchers find that they are not living up to their energy saving potential, due to a lack of coordinated controls with the existing HVAC system. The Pacific Northwest National Laboratory (PNNL), the Florida Solar Energy Center (FSEC), and The Levy Partnership are all leading projects across the country to address this problem. The goal for this body of work is to determine which control strategies provide the most …


Targeting The Best Performing Home Efficiency Programs With Advanced Metering Evaluation Supplemented By Simulation, Florida Solar Energy Center, Robin Vieira Aug 2020

Targeting The Best Performing Home Efficiency Programs With Advanced Metering Evaluation Supplemented By Simulation, Florida Solar Energy Center, Robin Vieira

FSEC Energy Research Center®

The authors investigated the impacts of seven residential rebate energy efficiency programs offered by a municipal utility. The evaluation examined energy use pre and post retrofit using the Advanced Metering Infrastructure (AMI) data, disaggregated by major end-use and weather-adjusted; and also by detailed simulations. Residences modeled were representative of typical participants for that measure based on factors such as year built, conditioned square feet and number of bedrooms.

Our analysis found the residential rebate programs to be of highly varied effectiveness, but important differences surfaced between the simulation and the AMI data evaluation. Not surprisingly, programs with larger samples tended …


Analysis Techniques For Evaluating Energy Conservation Programs Using Utility Ami Data, Florida Solar Energy Center, Richard Raustad Aug 2020

Analysis Techniques For Evaluating Energy Conservation Programs Using Utility Ami Data, Florida Solar Energy Center, Richard Raustad

FSEC Energy Research Center®

With the evolution of Advanced Metering Infrastructure (AMI) electric meters, utility companies now have direct access to whole building electricity use at a granular time scale. AMI data can be used for a variety of purposes beyond billing, for example, to evaluate the efficacy of energy conservation (EC) programs. Historical methods for calculating EC program savings include building simulation models and laboratory and/or field testing. With big data now available, which analysis methods are more likely to yield quality results?

In a recent project, the Orlando Utility Commission provided monitored AMI data from Oct 1, 2015 - Sep 27, 2018 …


Improving Energy Savings And Peak Demand Reduction Estimates Using Ami Data For Utility Commercial Rebate Programs, Florida Solar Energy Center, Karen Fenaughty Aug 2020

Improving Energy Savings And Peak Demand Reduction Estimates Using Ami Data For Utility Commercial Rebate Programs, Florida Solar Energy Center, Karen Fenaughty

FSEC Energy Research Center®

Solar reflective, or cool roofs, are a demonstrated method of reducing air conditioning energy, particularly in cooling-dominated climates. Similarly, efficient lighting or mechanical equipment replacement programs have a reputation for achieving large savings in c01mnercial buildings. Savings estimates for such measures have historically used monthly utility bills, which only provide a macroscopic view of utility program savings. Advanced Metering Infrastructure (AMI) is commonly used in the U.S. by utilities for residential and commercial customers and provides not only a valuable record of changing premise energy use and demand profiles but in much greater detail than utility bills, if desired.

Partnering …