Electrical and Computer Engineering Commons^™

Improvement Of Stability Of A Grid-Connected Inverter With An Lcl Filter By Robust Strong Active Damping And Model Predictive Control, Seungyong Lee

Graduate Theses and Dissertations

This study addresses development and implementation of robust control methods for a three-phase grid-connected voltage source inverter (VSI) accompanied by an inductive-capacitive-inductive (LCL) filter. A challenge of current control for the VSI is LCL filter resonance near to the control stability boundary, which interacts with the inverter control switching actions and creates the possibility of instability. In general, active damping is needed to stabilize the system and ensure robust performance in steady-state and dynamic responses. While many active damping methods have been proposed to resolve this issue, capacitor-current-feedback active damping has been most widely used for its simple implementation.

There …

An Accurate And Efficient Electro-Thermal Compact Model Of Sic Power Mosfet Including Third Quadrant Behavior, Arman Ur Rashid

Graduate Theses and Dissertations

Due to narrower bandgap and lower critical electric field, silicon (Si) power devices have reached their limit in terms of the maximum blocking voltage capability. Exploiting this limitation, wide bandgap devices, namely silicon carbide (SiC) and gallium nitride (GaN) devices, are increasingly encroaching on the lucrative power electronics market. Unlike GaN, SiC devices can exploit most of the established fabrication techniques of Si power devices. Having substrate of the same material, vertical device structures with higher breakdown capabilities are feasible in SiC, unlike their GaN counterpart. Also, the excellent thermal conductivity of SiC, compared to GaN and Si, let SiC …

Realization Of Compact Electrochemical Sensing Systems On A Board And A Chip For A High-Density Sensor Array, Hyusim Park

Electrical Engineering Dissertations - Archive

The sensitive and cost-effective electrochemical sensors based on various classes of nanocomposites fabricated by different methods for the detection of target chemicals. Its application is boundless from reactive monitoring of food additives, human health to environmental safety. In proportion to electrochemical sensor’s usages, the researchers’ interests in electrochemical sensing system have been grown, especially in portable system to satisfy many of the requirements for on-site and in-situ measurements. The electrochemical sensing system is consisted of sensor and electric readout circuit. The one of the most efficient way to carry out the reading of a set of electrochemical sensors for portable …

Data-Driven Decision Making And Control Of Rational Agents, Patrik Kolaric

Electrical Engineering Dissertations - Archive

This dissertation studies the problem of data-driven optimal decision making. The 4main contributions of this work are listed here. First, we develop a model-based and data-driven techniques for learning the cost of an Ex-pert agent. This ties fields of Inverse Optimal Control and Inverse Reinforcement Learning and represents a first data-driven algorithm of this kind in the control community. Next, we have developed optimally adaptive dynamic control allocation mechanism that optimally re-configures redundant actuators in a model-free fashion, that is, based on collected data. This work pushed the multiple frontiers of control allocation research, since state-of-the-art control allocation was Next, …

A Novel Hybrid Gwo-Ls Estimator For Harmonic Estimation Problem In Time Varying Noisy Environment, Muhammad Abdullah, Tahir N. Malik, Ali Ahmed, Muhammad F. Nadeem, Irfan A. Khan, Rui Bo

Electrical and Computer Engineering Faculty Research & Creative Works

The power quality of the Electrical Power System (EPS) is greatly affected by electrical harmonics. Hence, accurate and proper estimation of electrical harmonics is essential to design appropriate filters for mitigation of harmonics and their associated effects on the power quality of EPS. This paper presents a novel statistical (Least Square) and meta-heuristic (Grey wolf optimizer) based hybrid technique for accurate detection and estimation of electrical harmonics with minimum computational time. The non-linear part (phase and frequency) of harmonics is estimated using GWO, while the linear part (amplitude) is estimated using the LS method. Furthermore, harmonics having transients are also …

Fuzzyart: An R Package For Art-Based Clustering, Louis Steinmeister, Donald C. Wunsch

Electrical and Computer Engineering Faculty Research & Creative Works

Adaptive Resonance Theory (ART) was introduced by Steven Grossberg as a theory of human cognitive information processing (Grossberg 1976, 1980). Extending the capabilities of the ART 1 model, which can learn to categorize patterns in binary data, fuzzy ART as described in (Carpenter, Grossberg, and Rosen 1991) has become one of the most commenly used Adaptive Resonance Theory models (Brito da Silva, Elnabarawy, and Wunsch 2019). By incorporating fuzzy set theroy operators, fuzzy ART is capable of learning from binaray and bounded real valued data. Its advantage over other unsupervised learning algorithms lies in the flexibility of the learning rule. …

Design Of Control Logic And The Human-Machine Interface For A Demonstration Plant Growth Chamber Implemented On A Programmable Logic Controller, Rachael Koehler

Biological and Agricultural Engineering Undergraduate Honors Theses

This honors thesis covers the planning, development, and implementation of system controls and human-machine interface (HMI) for a demonstration plant growth chamber. The work is a continuation of an ongoing project to be used as an educational and recruiting tool manifesting the skills acquired from the Biological and Agricultural Engineering Department at the University of Arkansas’ College of Engineering. This work includes emergency controls, overall design interface, and controls for both the aeration and lighting subsystems of the growth chamber. Overall design interface controls established included development of two user modes, Administrator and Visitor. The Administrator user will have full …

Performance And Economics Of Solar Inverters And Module Level Power Electronics In A 1 Mw Photovoltaic System, Maxwell Criswell

Biological and Agricultural Engineering Undergraduate Honors Theses

Photovoltaic solar panels convert sunlight to electricity in the form of direct current; therefore, a necessary component of every photovoltaic system is an inverter to convert the electricity to usable alternating current. There are various commercially available inverter technologies manufactured today such as microinverters, string inverters, and central inverters, as well as module level power electronic devices such as DC optimizers that are capable of improving system performance in string and central inverter systems. This thesis compares the performance and economics of five different inverter and module level power electronic systems through model simulation using Helioscope software. The five alternatives …

Development Of A Two-Level Warping Algorithm And Its Application To Speech Signal Processing, Al-Waled H. Al-Dulaimi

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

In many different fields there are signals that need to be aligned or “warped” in order to measure the similarity between them. When two time signals are compared, or when a pattern is sought in a larger stream of data, it may be necessary to warp one of the signals in a nonlinear way by compressing or stretching it to fit the other. Simple point-to-point comparison may give inadequate results, because one part of the signal might be comparing different relative parts of the other signal/pattern. Such cases need some sort of alignment todo the comparison. Dynamic Time Warping ( …

Algorithms For The Calibration And Correction Of Texel Images Using Inertial Measurement Updates, Trevor C. Welch

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A 3D terrain map can be developed to survey the earth’s surface and provide scientists with a method of accurately modeling terrain. Some of the applications include agricultural surveys, disaster management, and object classification. In order to develop a 3D terrain map, a sensor must capture all of the data to create the map. This 3D mapping tool can be made by combining a sensor that take samples of points on the earth’s surface and combines that with a digital camera that takes an image and lays it across those samples of the earth.

In order to take data over …

Dynamic Analysis Of A Microgrid Powered With An Inverter And Machine-Based Distributed Resources, Brandon William Blackstone

UNLV Theses, Dissertations, Professional Papers, and Capstones

The proliferation of renewable distributed energy resources, particularly photovoltaic (PV) power systems, and the increasing need for a reliable power supply has led to the concept of microgrids, a mini-grid that consists of locally connected power generation units and needs, able to operate connected or disconnected from the utility grid, using controlled and coordinated methods to provide for the users of the microgrid the best possible conditions for their needs. The main technical issues facing microgrids include some of the following, seamless transition from stand-alone to utility grid connected operation, how to preserve frequency and voltage stability, and provide the …

Infants' Facial Emotion Recognition, Umme Fatema

UNLV Theses, Dissertations, Professional Papers, and Capstones

Facial Emotion Recognition (FER) has become a popular computer vision topic and attracted a lot of researchers. However, these researches mostly focus on adult facial emotion. Infants’ facial structure and expression of emotions differ from adults’. That is why our target is to create a model that particularly focuses on infants’ facial emotions. In this work, we classify three types of emotions: positive, negative, and neutral. Two datasets are used in this work. One is an image-based dataset named ‘The City’ that consists of 154 images of infants aged 0-12 months. Another is the Rebel Dataset from the Department of …

Healthy Aging In Place: An Integrated Smart Home Using Alexa-Compatible Technology, Tyler Kryst

UNLV Theses, Dissertations, Professional Papers, and Capstones

The purpose of this research was to address current healthcare concerns among the aging population. Around the globe, the average life expectancy is projected to continue increasing resulting in a higher prevalence of age-related disease. With the ever-increasing capabilities of modern technology, it is necessary to apply this technology to increase the health and safety of older adults. This work had three objectives. The first objective was the establishment of an integrated smart home aimed at creating a healthy aging-in-place environment through the use of Alexa. The second objective was the development and integration of a completely custom health device …

Patient-Specific Finite Element Analysis For Mandibular Fracture Fixation, Ethan Snyder

UNLV Theses, Dissertations, Professional Papers, and Capstones

This thesis proposes an approach for Finite Element Analysis (FEA) of mandibular fracture fixation. Using a Computerized Tomography (CT) scan of mandible obtained from a specific person, the material characteristics, density and modulus of elasticity, were determined from a set of discrete points within the mandible that are 1mm spaced based on the Hounsfield Units of these points. The mandible geometry was sectioned to simulate a fracture. Muscle and mastication forces were added to replicate post-surgery loading. Using a standard linear miniplate, this material model was compared with two commonly used mandibular cortical shell bone models: isotropic and orthotropic. A …

Design And Control Of A Peristaltic Pump To Simulate Left Atrial Pressure In A Conductive Silicone Model, Jeremy Collins

Mechanical Engineering Undergraduate Honors Theses

According to the CDC, atrial fibrillation is responsible for more than 454,000 hospitalizations and approximately 158,000 deaths per year. A common treatment for atrial fibrillation is catheter ablation, a process in which a long flexible tube is guided through the femoral artery and to the source of arrhythmia in the heart, where it measures the electrical potential at various locations and converts problematic heart tissue to scar tissue via ablation. This paper details the design and control of a low-cost ($400) peristaltic pump system using repetitive control to replicate blood pressure in the left atrium in a conductive silicone model …

Aiming For The Sun- Averting The Fate Of Icarus: De-Risking Solar Energy Projects, Manu Srivastava

Asian Management Insights

Climate change is increasingly accepted as an existential threat to civilisation and ‘business as usual’ is considered a luxury we cannot afford any more.

Characterization Of The Rf Magnetron Sputtered P-Si & N-Si On Si Substrate And Effect Of Process Parameters On Their Structural & Electrical Properties, Prosanto Biswas

Theses and Dissertations

In our work, we applied Taguchi Signal-to-noise (SNR) analysis to investigate the effect of varying three process parameters, namely- sputtering power, working pressure, and Ar gas flow rate on the surface and morphological properties of the RF sputtered p-Si and n-Si on Si substrate. We also inspected the contribution of process parameters on those properties by applying Analysis of Variance (ANOVA). Characteristics of thin films fabricated by RF magnetron sputtering vary with the recipes. Process parameters such as power, pressure, process gas flow rate, substrate temperature, and target to substrate distance determine the quality of the thin films. Some of …

Impact Of Wind Generation On Transmission Voltage Support During Weak Grid, Yugo Isogai

Electrical Engineering Undergraduate Honors Theses

Today, there are concerns about the effects of high wind penetration on electric power system operations. This is due to the more distributed nature of wind turbine generation and the corresponding multi-path power flows on the electric power transmission grid. In particular, the higher line impendences associated with inverter-based wind generation results in larger voltage fluctuation under varying load. This may results in conditions where even after a fault condition has been cleared, the transmission system voltages may not recover. Therefore, this paper concentrates on the impact of weak grid condition for voltage instability. To approach it, a 6-bus system …

A Study Of Deep Reinforcement Learning In Autonomous Racing Using Deepracer Car, Mukesh Ghimire

Honors Theses

Reinforcement learning is thought to be a promising branch of machine learning that has the potential to help us develop an Artificial General Intelligence (AGI) machine. Among the machine learning algorithms, primarily, supervised, semi supervised, unsupervised and reinforcement learning, reinforcement learning is different in a sense that it explores the environment without prior knowledge, and determines the optimal action. This study attempts to understand the concept behind reinforcement learning, the mathematics behind it and see it in action by deploying the trained model in Amazon's DeepRacer car. DeepRacer, a 1/18^th scaled autonomous car, is the agent which is trained …

The Linear And Non-Linear Relationships Between Peripheral Venous Pressure, Arterial Circulation, And Patient Factors, Lauren Crimmins

Biomedical Engineering Undergraduate Honors Theses

Peripheral venous pressure (PVP) can be used to measure blood volume status with a minimally invasive procedure. The pediatric cohort undergoing surgery for pyloric stenosis was studied to determine how arterial circulation and patient factors linearly impact PVP. The relationship between PVP and these confounding factors can provide valuable information for future PVP researchers.

To investigate the linear relationship between PVP and electrocardiogram (ECG) the waveforms were transformed into the frequency domain. A power spectral density was plotted, and the Pearson correlation coefficients were calculated for both preoperative and intraoperative settings. Linear regression models were computed for PVP and varying …

A Comparison Of Medical Article Transport Approaches, Andrew White

Honors Scholar Theses

Our senior design project is to develop a product named the Smartbox - a container capable of safely carrying and monitoring medical articles and accommodate a UAV drone carrying the container. These medical articles include sensitive medicines and human organs for transplantation. Speed, safety, and reliability are a must in this field, as the stakes if a payload is lost or improperly maintained can be life threatening. This project aims to improve on the existing medical transport logistics chains in use today. Time is the most important factor in transportation: many organs simply cannot survive outside of the human body …

Path Planning With Deep Neural Networks, Paul Simmerling, Brendan Sayers, Paulo Alcantara Silva

Honors Scholar Theses

This report will cover the work and plans of the ECE 2107 Senior design team. The goal of the project is to design and build a fully autonomous self-driving car. This car will have a complete sensor suite including LIDAR, an IMU, a camera, and encoders. It will be based on a multi-level system where the highest level uses a neural network for advanced signal processing and analysis. The current state of the project is discussed as well as the final results. Project management and other constraints will be briefly investigated. This team is building a self driving car testbed …

Metamaterial Inspired Multi-Band Antenna For Mm-Wave 5g Wireless Communication, Mohammad Ashif Hossain Chowdhury

Theses and Dissertations

Due to the constant demand for speed and capacity in wireless communication, mm-wave bands are getting special interest. Most of the high-speed 5G bands are in the mm-wave region. As the mm-wave signal is prone to absorption and faces a significant free space path loss, an antenna with narrow beam, high gain, and high efficiency is required. The antenna also needs to be working in multiple frequencies, as there is a multitude of mm-wave frequencies allocated by the regulator for 5G communication. In this study, we designed an antenna capable of working in high 5G bands consisting of 25GHz,28GHz, and …

Learning To Detect Pedestrian Flow In Traffic Intersections From Synthetic Data, Abhijit Baul

Theses and Dissertations

Detecting pedestrian flow in different directions at at traffic-intersection has always been a challenging task. Challenges include different weather conditions, different crowd densities, occlusions, lack of available data, and so on. The emergence of deep learning and computer vision algorithms has shown promises to deal with these problems. Most of the recent works only focus on either detecting combined pedestrian flow or counting the total number of pedestrians. In this work, we have tried to detect not only combined pedestrian flow but also pedestrian flow indifferent directions. Our contributions are, 1) we are introducing a synthetic pedestrian dataset that we …

Designing Mimo Omnidirectional Millimeter-Wave Metamaterialantenna For 5g Communications, Khan Md Zobayer Hassan

Theses and Dissertations

A highly efficient, low profile, wideband metamaterial antenna is presented for mm-wave 5G communications. The designed metamaterial resonator structure works as a radiator and operates in the FCC auctioned 28 GHz frequency spectrum (27.5 - 28.350 GHz). The proposed antenna is fabricated on a 10.3mm x 10.3mm and .0787 mm thick Rogers RT5880/Duroid substrate and probe feed is used as the feeding mechanism. The effect of different design parameters on the performance of the antenna is examined and then optimized for the best possible performance. The designed antenna shows wideband characteristics with an impedance bandwidth of 2.22 GHz (27.49 – …

Planning A Renewable Power System In Texas As An Introduction To Smart Power Grid, Ghaleb S. Al Duhni

Theses and Dissertations

Design electrical systems from six renewable energy sources: photovoltaic, wind energy, geothermal, concentrated solar energy, biomass energy, and hydropower in addition to a storage system in the state of Texas, This power system converts the electric system in Texas into a 100 % renewable energy power system. Optimization technique has applied to the results to make the system economical and reduce the wasting resources, this system is considered as decentralized as well which is a great advantage for achieving the smart grid technology compared with the conventional plants where the generation parts are deposed in a small part of the …

Robust Distributed Formation Control Of Uavs With Higher-Order Dynamics, Md Nur-A-Adam Dony

Theses and Dissertations

In this thesis, we introduce distributed formation control strategies to reach an intended linear formation for agents with a diverse array of dynamics. The suggested technique is distributed entirely, does not include inter-agent cooperation or a barrier of orientation, and can be applied using relative location information gained by agents in their local cooperation frames. We illustrate how the control optimized for agents with the simpler dynamic model, i.e., the dynamics of the single integrator, can be expanded to holonomic agents with higher dynamics such as quadrotors and non-holonomic agents such as unicycles and cars. Our suggested approach makes …

Design Of Multi-Layered Lenses For Resolusion Enhancement, S. M. Zia Uddin

Theses and Dissertations

Lenses are important optical device having numerous applications in our day-to-day life. As the conventional lenses, we use concave or convex lenses. These lenses are made with natural materials and the image quality imperfect. Furthermore, they are bulky, and design is complex. Consequently, mass production is difficult.

The shapes of entrance and exit faces of lenses has impact on its imaging capability. The Lens material also play a vital role for reconstructing the image. Flat lenses can be considered as a good alternative of the conventional lenses. One of the advantages of this Flat lenses is that it can restore …

Cortical Dynamics Of Language, Kiefer Forseth

Dissertations and Theses (Open Access)

The human capability for fluent speech profoundly directs inter-personal communication and, by extension, self-expression. Language is lost in millions of people each year due to trauma, stroke, neurodegeneration, and neoplasms with devastating impact to social interaction and quality of life. The following investigations were designed to elucidate the neurobiological foundation of speech production, building towards a universal cognitive model of language in the brain. Understanding the dynamical mechanisms supporting cortical network behavior will significantly advance the understanding of how both focal and disconnection injuries yield neurological deficits, informing the development of therapeutic approaches.

Dynamic Route Optimization For Waste Collection In Smart City, Abdullah Suliman Alwabli

Theses and Dissertations

Waste collection is a critical component of the municipal service to the community within urban set-ups. Increasing levels of waste generation present significant challenges in urban areas due to unprecedented population growth. Consequently, due to the accumulating amounts of waste, waste management has become a primary concern. Several problems also emanate from the current inadequate and inefficient waste management systems that rely on non-scientific techniques. This paper proposes using IoT-based smart bins to improve the waste management process by optimizing waste collection. Al-Awali District in the Saudi Arabian city of Mecca will be the main focus of this study, where …