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Electronic Theses and Dissertations

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Full-Text Articles in Engineering

Power System Resilience Enhancement Using Artificial Intelligence, Rozhin Eskandarpour Jan 2019

Power System Resilience Enhancement Using Artificial Intelligence, Rozhin Eskandarpour

Electronic Theses and Dissertations

Extreme weather events and natural disasters are the major cause of power outages in the United States. An accurate forecast of component outages and the resultant load curtailment in response to extreme events is an essential task in pre- and post-event planning, recovery and hardening of power systems. Power system resilience improvement is investigated in this work from component outage prediction to identifying the potential power outages in the system to estimating probable load curtailment due to these outages and offering methods for grid hardening. Initially, two machine learning based prediction methods are proposed to determine the potential outage of …


Solar Forecasting And Integration In Power Systems, Mohana Alanazi Jan 2019

Solar Forecasting And Integration In Power Systems, Mohana Alanazi

Electronic Theses and Dissertations

Renewable energy resources are becoming critical players in the electricity generation sector, primarily due to viability in combating global warming, effectiveness in reducing pollution caused by fossil fuel based generation, and diversifying energy mix to ensure energy security and sustainability. Solar energy is one of the most common types of renewable energy that has grown rapidly over the past decade and is anticipated to grow even faster in the future. Power supply from renewable resources is forecasted to surpass other types of generation in a foreseeable future. Numerous factors, including but not limited to the dropping cost of solar technology, …


Optimal Design And Planning Of Hybrid Ac/Dc Microgrid, Hossein Lotfi Jan 2019

Optimal Design And Planning Of Hybrid Ac/Dc Microgrid, Hossein Lotfi

Electronic Theses and Dissertations

The traditional approach for microgrid design and deployment has been mainly focused on AC systems. DC microgrids, however, are gaining attention due to numerous advantages they provide over AC microgrids, such as removing the need for synchronization and frequency adjustment as well as appropriateness in supporting DC loads and distributed energy resources (DERs). Moreover, considering that both AC and DC DERs are utilized in microgrids, hybrid microgrids would provide viable and economic solutions as they can potentially eliminate the need for AC-to-DC or DC-to-AC voltage conversions. This dissertation focuses on a hybrid microgrid planning model with the objective of minimizing …


Radar Detection, Tracking And Identification For Uav Sense And Avoid Applications, Erik George Moore Jan 2019

Radar Detection, Tracking And Identification For Uav Sense And Avoid Applications, Erik George Moore

Electronic Theses and Dissertations

Advances in Unmanned Aerial Vehicle (UAV) technology have enabled wider access for the general public leading to more stringent flight regulations, such as the "line of sight" restriction, for hobbyists and commercial applications. Improving sensor technology for Sense And Avoid (SAA) systems is currently a major research area in the unmanned vehicle community. This thesis overviews efforts made to advance intelligent algorithms used to detect, track, and identify commercial UAV targets by enabling rapid prototyping of novel radar techniques such as micro-Doppler radar target identification or cognitive radar. To enable empirical radar signal processing evaluations, an S-Band and X-Band frequency …


Proactive Monitoring, Anomaly Detection, And Forecasting Of Solar Photovoltaic Systems Using Artificial Neural Networks, Ahmad Almadhor Jan 2019

Proactive Monitoring, Anomaly Detection, And Forecasting Of Solar Photovoltaic Systems Using Artificial Neural Networks, Ahmad Almadhor

Electronic Theses and Dissertations

The world of energy sustainability landscape is witnessing high proliferation of smartgrids and microgrids, it has become significant to use intelligent tools to design, operate and maintain such crucial systems in our lives. Solar energy is an intermittent source and purely Photovoltaic (PV) based, or PV and storage based smartgrids require characterization and modelling of PV resources for an effective planning and effective operations. This dissertation familiarizes briefly the existing tools for design, monitoring, forecasting and operation of a solar system in smart electric grids infrastructure and proposes a unique application-based infrastructure to monitor, operate, forecast and troubleshoot a working …


A Study On Distributed Generation With A Focus On Solar Power, Shravan Kumar Tomar Jan 2019

A Study On Distributed Generation With A Focus On Solar Power, Shravan Kumar Tomar

Electronic Theses and Dissertations

Centralized generation is when electric power is produced in a large scale of tens of MWs and is located away from the end user. This kind of production is connected to a series of high-voltage transmission lines. Electricity is then delivered to the end user through a network of distribution grids. Centralized generation tend to have multiple end user with multiple user profiles.

Distributed Generation is when is produced in a small scale and is located at the site of or very close to the end user. There are many ways distributed generation can be achieved, Solar power being the …


Coupling Of Light's Orbital Angular Momentum To A Quantum Dot Ensemble, Alaa A. Bahamran Jan 2019

Coupling Of Light's Orbital Angular Momentum To A Quantum Dot Ensemble, Alaa A. Bahamran

Electronic Theses and Dissertations

We theoretically and experimentally investigate the transfer of orbital angular momentum from light to an ensemble of semiconductor-based nanostructures composed of lead sulfide quantum dots. Using an ensemble of quantum dots offers a higher cross-section and more absorption of twisted light fields compared to experimentally challenging single-nanostructure measurements. However, each quantum dot (except for on-center) sees a displaced light beam parallel to its own axis of symmetry. The transition matrix elements for the light-matter interaction are calculated by expressing the displaced light beam in terms of the appropriate light field centered on the nanoparticles. The resulting transition rate induced by …


Empirical Evaluation Of Ground, Ceiling, And Wall Effect For Small-Scale Rotorcraft, Stephen Austin Conyers Jan 2019

Empirical Evaluation Of Ground, Ceiling, And Wall Effect For Small-Scale Rotorcraft, Stephen Austin Conyers

Electronic Theses and Dissertations

Ground effect refers to the apparent increase in lift that an aircraft experiences when it flies close to the ground. For helicopters, this effect has been modeled since the 1950's based on the work of Cheeseman and Bennett, perhaps the most common method for predicting hover performance due to ground effect. This model, however, is based on assumptions that are often not realistic for small-scale rotorcraft because it was developed specifically for conventional helicopters. It is clear that the Cheeseman-Bennett model cannot be applied to today's multirotor UAVs. Experimental findings suggest that some of the conventional thinking surrounding helicopters cannot …


Synergistic Environmental Aging Of Glass Reinforced Polymer Composites, Tianyi Lu Jan 2019

Synergistic Environmental Aging Of Glass Reinforced Polymer Composites, Tianyi Lu

Electronic Theses and Dissertations

Synergistic effects involved in the environmental degradation of Glass Reinforced Polymer (GRP) composites were examined and a novel synergistic aging model was proposed in this study. Six GRPs based on glass fibers with four different polymer resins and six pure polymer thermoplastic resins were exposed either individually or in combination to ultraviolet (UV) radiation, water condensation and elevated temperature for approximately 1000 h. The composites and polymers were monitored for weight changes as a function of time and their surfaces were examined after the tests using optical and scanning electron microscopes (SEM). Photodegradation of the polymer matrices was analyzed by …


Capturing Transmission And Distribution Connected Wind Energy Variability, Abdulaziz Alanazi Jan 2019

Capturing Transmission And Distribution Connected Wind Energy Variability, Abdulaziz Alanazi

Electronic Theses and Dissertations

Although renewable energy provides a viable solution to address ongoing challenges of the economy and the environment in modern power systems, the variable generation of this technology results in major technical challenges for system operators. This issue is becoming more severe as the penetration of renewable generation is increasing. This dissertation addresses the variability challenge of renewable energy resources in transmission and distribution levels of modern power systems.

For transmission level, this dissertation focuses on wind generation fluctuation. Three methods of reducing wind generation fluctuation are investigated from an economic perspective, including (a) dumping the wind generation, (b) using battery …


Design And Analysis Of A Non-Isolated High Gain Step-Up Cuk Converter, Yasser Almalaq Jan 2019

Design And Analysis Of A Non-Isolated High Gain Step-Up Cuk Converter, Yasser Almalaq

Electronic Theses and Dissertations

Renewable energy sources, such as solar energy, are desired for both economic and ecological issues. These renewable energy sources are plentiful in nature and have a terrific capability for power generation. The only drawback of solar energy, which is one of the best forms of energy sources, is that the output has a low voltage and needs to be stepped up in order to be inserted into the DC grid or an inverter for AC applications. To overcome this drawback, a high gain DC-DC power converter is required in this kind of system. These power converters are needed for a …


Improvements Of And Extensions To Fsmweb: Testing Mobile Apps, Ahmed Fawzi Al Haddad Jan 2019

Improvements Of And Extensions To Fsmweb: Testing Mobile Apps, Ahmed Fawzi Al Haddad

Electronic Theses and Dissertations

A mobile application is a software program that runs on mobile device. In 2017, 178.1 billion mobile apps downloaded and the number is expected to grow to 258.2 billion app downloads in 2022 [19]. The number of app downloads poses a challenge for mobile application testers to find the right approach to test apps. This dissertation extends the FSMWeb approach for testing web applications [50] to test mobile applications (FSMApp). During the process of analyzing FSMWeb how it could be extended to test Mobile Apps, a number of shortcomings were detected which we improved upon. We discuss these first. We …


Protection Of High-Voltage Transformer Bushings And Other Brittle Structures Against Impact, Christine Nichole Henderson Jan 2019

Protection Of High-Voltage Transformer Bushings And Other Brittle Structures Against Impact, Christine Nichole Henderson

Electronic Theses and Dissertations

This dissertation contributes unique approaches to improve the fundamental understanding of the impact behavior of porcelain high-voltage (HV) transformer bushings under high-velocity impact, with a focus on their protection with feasible methods which could be quickly applied in service to prevent vandalism and other undesirable impact situations. The bushings are brittle and pressurized; prone to explosive damage when hit by a high-velocity projectile. Damaged bushings can destroy transformers and entire substations in complex fashions. This can put the power grid at risk for cascading failures and electrical blackouts, affecting consumers. Therefore, suggesting practical approaches which could be used to protect …


Increasing Distribution Grid Hosting Capacity Through Wire And Non-Wire Solutions, Abdulrahman N. Almazroui Jan 2019

Increasing Distribution Grid Hosting Capacity Through Wire And Non-Wire Solutions, Abdulrahman N. Almazroui

Electronic Theses and Dissertations

Increased deployment of distributed generation (DG) can adversely impact the operational performance of distribution networks. This increment can potentially change network power flow and result in several operational issues such as reduced power quality, overvoltage, and ineffective protection. In order to quantify the degradation bounds of distribution operation due to increasing DG integration, the concept of hosting capacity is introduced. The aim of this thesis is to increase the DG hosting capacity in distribution network by proposing several wire and non-wire solutions. To this end, these solutions include network reconfiguration, reactive power control, and energy storage system deployment. The network …


Nonlinear Controller Design For Uavs With Time-Varying Aerodynamic Uncertainties, Michail G. Michailidis Jan 2019

Nonlinear Controller Design For Uavs With Time-Varying Aerodynamic Uncertainties, Michail G. Michailidis

Electronic Theses and Dissertations

Unmanned Aerial Vehicles (UAVs) are here and they are here to stay. Unmanned Aviation has expanded significantly in recent years and research and development in the field of navigation and control have advanced beyond expectations. UAVs are currently being used for defense programs around the world but the range of applications is expected to grow in the near future, with civilian applications such as environmental and aerial monitoring, aerial surveillance and homeland security being some representative examples. Conventional and commercially available small-scale UAVs have limited utilization and applicability to executing specific short-duration missions because of limitations in size, payload, power …


A Policy Mechanism For Federal Recommendation Of Security Standards For Mobile Devices That Conduct Transactions, Ariel Huckabay Jan 2019

A Policy Mechanism For Federal Recommendation Of Security Standards For Mobile Devices That Conduct Transactions, Ariel Huckabay

Electronic Theses and Dissertations

The proliferation of mobile devices in the BRIC countries has prompted them to develop policies to manage the security of these devices. In China, mobile devices are a primary tool for payments. As a result, China instituted in 2017 a cyber security policy that applies to mobile devices giving China broad authority to manage cyber threats. The United States has a similar need for a cyber policy. Mobile devices are likely to become a primary payment tool in the United States soon. DHS has also identified a need for more effective security policy in mobile devices for government operations. This …


Application Of Microgrids In Supporting The Utility Grid, Alireza Majzoobi Jan 2019

Application Of Microgrids In Supporting The Utility Grid, Alireza Majzoobi

Electronic Theses and Dissertations

Distributed renewable energy resources have attracted significant attention in recent years due to the falling cost of the renewable energy technology, extensive federal and state incentives, and the application in improving load-point reliability. This growing proliferation, however, is changing the traditional consumption load curves by adding considerable levels of variability and further challenging the electricity supply-demand balance. In this dissertation, the application of microgrids in effectively capturing the distribution network net load variability, caused primarily by the prosumers, is investigated. Microgrids provide a viable and localized solution to this challenge while removing the need for costly investments by the electric …


Paving The Way For Multidisciplinary Smart Campus Infrastructure: Leveraging Du's Unique Campus For The Advancement Of Smart Campus Culture, Camerron T. Mismash Jan 2019

Paving The Way For Multidisciplinary Smart Campus Infrastructure: Leveraging Du's Unique Campus For The Advancement Of Smart Campus Culture, Camerron T. Mismash

Electronic Theses and Dissertations

Institutions are embracing smart technologies to reap their benefits while simultaneously innovating new uses. From localized renewable energy generation to health monitoring and everything in between, academic campuses globally are paving the way for smart technology application. Eight primary categories have been identified in which institutions are applying smart technologies. Energy development is on the forefront of these smart initiatives. The University of Denver has begun its Smart Campus Initiative by implementing a revolving fund to invest in campus improvements related to the offset of carbon. By comparing how institutions are investing in smart campus initiatives and analyzing costs associated …


Distribution Level Building Load Prediction Using Deep Learning, Abdulaziz S. Almalaq Jan 2019

Distribution Level Building Load Prediction Using Deep Learning, Abdulaziz S. Almalaq

Electronic Theses and Dissertations

Load prediction in distribution grids is an important means to improve energy supply scheduling, reduce the production cost, and support emission reduction. Determining accurate load predictions has become more crucial than ever as electrical load patterns are becoming increasingly complicated due to the versatility of the load profiles, the heterogeneity of individual load consumptions, and the variability of consumer-owned energy resources. However, despite the increase of smart grids technologies and energy conservation research, many challenges remain for accurate load prediction using existing methods. This dissertation investigates how to improve the accuracy of load predictions at the distribution level using artificial …


Study Of Acceleration Sensitivity And Nonlinear Behavior In Silicon-Based Mems Resonators, Beheshteh Khazaeili Najafabadi Jan 2019

Study Of Acceleration Sensitivity And Nonlinear Behavior In Silicon-Based Mems Resonators, Beheshteh Khazaeili Najafabadi

Electronic Theses and Dissertations

The focus of this work is to study nonlinear behavior in silicon-based micro-resonators and more specifically develop models that could predict acceleration sensitivity and amplitude-frequency nonlinearity in such resonators. Acceleration sensitivity in silicon bulk-acoustic wave (BAW) oscillators is studied and a correlation between the resonator alignment to different crystalline planes of silicon and the observed acceleration sensitivity is established. It is shown both with experiment and the proposed finite element model, that the oscillator vibration sensitivity is significantly lower when the silicon-based lateral-extensional (LE) mode resonator is aligned to < 110 > orientation compared to when the same resonator is aligned to < 100 > . …


Synthesis Of Two-Dimensional Molybdenum Disulfide Nanostructures Using Molybdenum Trioxide Thin Film Via Chemical Vapor Depostion, Vanessa Charles Jan 2019

Synthesis Of Two-Dimensional Molybdenum Disulfide Nanostructures Using Molybdenum Trioxide Thin Film Via Chemical Vapor Depostion, Vanessa Charles

Electronic Theses and Dissertations

Two dimensional (2D) materials-based nanostructures have attracted much attention due to their unique properties which exhibit promising prospects for application in catalysis and energy storage devices. Control growth method is important in synthesizing these nanostructures. Chemical vapor deposition (CVD) is a powerful method that provides scalability and controllable way to grow high quality 2D materials-based nanostructures. Here, we report a novel CVD growth method of 2D molybdenum disulfide (MoS2) based different structures in which thin film of molybdenum trioxide (MoO3) was used as the source of molybdenum (Mo), while sulfur (S) powder was used for the chalcogen precursor. Precise control …


Modeling And Control Of The Ugv Argo J5 With A Custom-Built Landing Platform, Mohammed Aldaoseri Alghanim Jan 2019

Modeling And Control Of The Ugv Argo J5 With A Custom-Built Landing Platform, Mohammed Aldaoseri Alghanim

Electronic Theses and Dissertations

This thesis aims to develop a detailed dynamic model and implement several navigation controllers for path tracking and dynamic self-leveling of the Argo J5 Unmanned Ground Vehicle (UGV) with a custom-built landing platform. The overall model is derived by combining the Argo J5 driveline system with the wheelsterrain interaction (using terramechanics theory and mobile robot kinetics), while the landing platform model follows the Euler-Lagrange formulation. Different controllers are, then, derived, implemented to demonstrate: i.) self-leveling accuracy of the landing platform, ii.) trajectory tracking capabilities of the Argo J5 when moving in uneven terrains. The novelty of the Argo J5 model …


Coupling Numerical Analysis Of Vibration And Thermal Buckling Of An Automotive Brake Disc, Joseph-Shaahu Shaahu Jan 2019

Coupling Numerical Analysis Of Vibration And Thermal Buckling Of An Automotive Brake Disc, Joseph-Shaahu Shaahu

Electronic Theses and Dissertations

An engaged brake system generates high temperature gradients in the brake rotor and brake pads. This high temperature gradient in turn induces thermal buckling. During high speed rotation, vibration is likely to occur in the system. In terms of a brake disc vibration will occur when there is a misalignment of the brake disc or thermoelastic instability (hot spot) forms on the brake rotor. Coupled and uncoupled problems of thermal buckling and vibration of a brake disc are analyzed and presented using finite element analysis in this paper. Thermal buckling depends on the direction of the high temperature gradient. Having …


Computational Fluid Dynamics Investigation Of A Novel Hybrid Comprehensive Stage Ii Operation For Single Ventricle Palliation, Marwan Hameed Jan 2019

Computational Fluid Dynamics Investigation Of A Novel Hybrid Comprehensive Stage Ii Operation For Single Ventricle Palliation, Marwan Hameed

Electronic Theses and Dissertations

Hypoplastic left heart syndrome (HLHS) is a type of heart defect where the left ventricle is underdeveloped or not developed, resulting in only a single functioning right ventricle. Approximately 7.5% of patients with congenital heart disease are born with a single ventricle (SV) which is accompanied by a spectrum of other malformations such as atrophied ascending aorta, atrial septal defects, and ventricular septal defects (VSD). The existing three-hybrid staged surgical approach serving as a palliative treatment for this anomaly entails multiple complications and achieves a survival rate of only 50%. To reduce the trauma associated with the second stage of …


On Distributed Estimation For Power Constrained Wireless Sensor Networks, Mojtaba Shirazi Jan 2019

On Distributed Estimation For Power Constrained Wireless Sensor Networks, Mojtaba Shirazi

Electronic Theses and Dissertations

We study distributed estimation (DES) problem in power and bandwidth constrained wireless sensor networks (WSNs), where several sensors make noisy observations of an unknown, and transmit a locally processed version of their observations to a fusion center (FC) over wireless channels. The FC reconstructs the unknown via fusing the received data from sensors. We explore the following problems: (i) we derive Bayesian Fisher information matrix (FIM) for bandwidth-constrained DES of a Gaussian vector with linear observation model, where sensors transmit their digitally modulated quantized observations to the FC over power-constrained fading channels. We develop two transmit power allocation schemes from …


Improving Traffic Safety At School Zones By Engineering And Operational Countermeasures, Md Hasibur Rahman Jan 2019

Improving Traffic Safety At School Zones By Engineering And Operational Countermeasures, Md Hasibur Rahman

Electronic Theses and Dissertations

Safety issues at school zone areas have been one of the most important topics in the traffic safety field. Although many studies have evaluated the effectiveness of various traffic control devices (e.g., sign, flashing beacon, speed monitoring display), there is a lack of studies exploring different roadway countermeasures and the relationship between school-related factors and crashes. In this study, the most crash-prone school zone was identified in Orange and Seminole Counties, Florida, based on crash rate. Afterward, a microsimulation network was built in VISSIM environment to test different roadway countermeasures in the school zones. Three different countermeasures: two-step speed reduction …


Physics-Guided Deep Learning For Power System Sate Estimation, Lei Wang Jan 2019

Physics-Guided Deep Learning For Power System Sate Estimation, Lei Wang

Electronic Theses and Dissertations

Conventionally, physics-based models are used for power system state estimation, including Weighted Least Square (WLS) or Weighted Absolute Value (WLAV). These models typically consider a single snapshot of the system without capturing temporal correlations of system states. In this thesis, a Physics-Guided Deep Learning (PGDL) method incorporating the physical power system model with the deep learning is proposed to improve the performance of power system state estimation. Specifically, inspired by Autoencoders, deep neural networks (DNNs) are utilized to learn the temporal correlations of power system states. The estimated system states are checked against the physics law by a set of …


Automated Synthesis Of Unconventional Computing Systems, Amad Ul Hassen Jan 2019

Automated Synthesis Of Unconventional Computing Systems, Amad Ul Hassen

Electronic Theses and Dissertations

Despite decades of advancements, modern computing systems which are based on the von Neumann architecture still carry its shortcomings. Moore's law, which had substantially masked the effects of the inherent memory-processor bottleneck of the von Neumann architecture, has slowed down due to transistor dimensions nearing atomic sizes. On the other hand, modern computational requirements, driven by machine learning, pattern recognition, artificial intelligence, data mining, and IoT, are growing at the fastest pace ever. By their inherent nature, these applications are particularly affected by communication-bottlenecks, because processing them requires a large number of simple operations involving data retrieval and storage. The …


Multi-Scale Modeling Of Viscoelastic Thin-Ply Composites, Milinda Madhusanka Yapa Yapa Hamillage Jan 2019

Multi-Scale Modeling Of Viscoelastic Thin-Ply Composites, Milinda Madhusanka Yapa Yapa Hamillage

Electronic Theses and Dissertations

Thin ply composites have been under the microscope of researchers for around two decades since Kawabe introduced the thin ply technology, in the Industrial Technology Center in Fukui, Japan. With the advancement of the technological aspects of manufacturing carbon fiber composites the tow spreading has improved so much as to reduce the thickness of a conventional ply up to even six-fold. Over the years carbon fiber composites have gained interest in space structures for reinforcement purposes in antennas, as structural elements that store strain energy and support the deployment of deployable structures, and in reflector concepts. Now thin-ply composites are …


Biomass Density Based Adjustment Of Lidar-Derived Digital Elevation Models: A Machine Learning Approach, Khalid Abdelwahab Jan 2019

Biomass Density Based Adjustment Of Lidar-Derived Digital Elevation Models: A Machine Learning Approach, Khalid Abdelwahab

Electronic Theses and Dissertations

Salt marshes are valued for providing protective and non-protective ecosystem services. Accurate digital elevation models (DEMs) in salt marshes are crucial for modeling storm surges and determining the initial DEM elevations for modelling marsh evolution. Due to high biomass density, lidar DEMs in coastal wetlands are seldom reliable. In an aim to reduce lidar-derived DEM error, several multilinear regression and random forest models were developed and tested to estimate biomass density in the salt marshes near Saint Marks Lighthouse in Crawfordville, Florida. Between summer of 2017 and spring of 2018, two field trips were conducted to acquire true elevation and …