Electrical and Electronics Commons^™

Energy Management And Control Of Smart Power Distribution Systems, Eric Galvan

Open Access Theses & Dissertations

With the development of distributed energy resources (DERs) and advancements in technology, microgrids (MGs) appear primed to become an even more integral part of the future distribution grid. In this transition to the smart power grid of the future, MGs must be properly managed and controlled to allow efficient integration of DERs. Over the past years, there has been rapid adoption of roof-top solar photovoltaic (PV) and battery electric vehicles (BEVs). Although roof-top solar PV and BEVs can provide environmental benefits (e.g., reduction of emissions), they also create various challenges for power system operators. For example, roof-top solar PV generation …

Hfo Detector Based On Eeg Mean Energy Change Detection, Raul Ontiveros

Open Access Theses & Dissertations

The main goal of this work is to support automated seizure prediction by identifying preictal states using multiple detectors of high-frequency oscillations (HFOs). Assessment of HFOs from a seizure onset zone may be facilitated using automatic HFO detectors. However, studies have shown that HFOs can be generated by physiological or pathological brain processes. Distinguishing between pathological and physiological HFOs is challenging due to a lack of discriminant information in signals' morphology and other characteristics. Other complicating factors include a lack of consistency in definitions of HFO frequency ranges, the need for expert verification of HFO detection, and lack of robustness …

Conductivity Modulation In Strained 2d Transition- Metal- Dichalcogenides Via Micro- Electro- Mechanical Actuation, Aldo Ivan Vidaña

Open Access Theses & Dissertations

In this thesis, strain-induced conductivity modulation in bi-layer molybdenum disulfide (MoS2) flakes is experimentally investigated and modeled. Uniaxial tensile strain in the MoS2 flakes is achieved using a micro-electro-mechanical (MEM) actuator. Conductivity ratios up to 400 are demonstrated. Theoretical predictions of conductivity versus applied voltage in the MEMS-MoS2 device match experimental data reasonably well using only the effective width of the TMDC flakes as the sole fitting parameter. The amount of strain induced in the MoS2 flakes was determined to be as high as 2.7% for one flake using the model fitted to the experiment data. The switching energy required …

Parallelization And Scalability Analysis Of The \\[1pc] 3d Spatially Variant Lattice Algorithm, Henry Roger Moncada Lopez

Open Access Theses & Dissertations

The purpose of this research is to design a faster implementation of an algorithm to generate 3D spatially variant lattices (SVL) and improve its performance when it is running on a parallel computer system. The algorithm is used to synthesize a SVL for a periodic structure. The algorithm has the ability to spatially vary the unit cell, the orientation of the unit cells, lattice spacing, fill fraction, material composition, and lattice symmetry. The algorithm produces a lattice that is smooth, continuous and free of defects. The lattice spacing remains strikingly uniform even when the lattice is spatially varied. This is …

Superpixel-Based Unsupervised Hyperspectral Unmixing, Jiarui Yi

Open Access Theses & Dissertations

Recently, superpixel-based approaches have been proposed for hyperspectral unmixing. The basic assumption of this approach is that the superpixel over-segmentation segments the image into small homogeneous areas. A low-dimensional (LD) image representation is obtained by using the average of the superpixels, which are then used in other image processing tasks up the processing chain. Due to superpixel-segmentation algorithm limitations, the region inside a superpixel may not be homogeneous. Therefore, the average may not be an adequate representation for the superpixel, leading to inaccuracies in the low dimensional representation resulting in errors in the image processing tasks or analysis. Here we …

Analysis Of High Performance Scientific Programming Workflows, Withana Kankanamalage Umayanganie Klaassen

Open Access Theses & Dissertations

Substantial time is spent on building, optimizing and maintaining large-scale software that is run on supercomputers. However, little has been done to utilize overall resources efficiently when it comes to including expensive human resources. The community is beginning to acknowledge that optimizing the hardware performance such as speed and memory bottlenecks contributes less to the overall productivity than does the development lifecycle of high-performance scientific applications. Researchers are beginning to look at overall scientific workflows for high performance computing. Scientific programming productivity is measured by time and effort required to develop, configure, and maintain a simulation experiment and its constituent …

People Detection From Time-Of-Flight Imagery With Inpainting-Based Preprocessing, Basavarajaiah Totada

Open Access Theses & Dissertations

The Thesis describes a method of detection and tracking of people using depth images captured by a Time-of-Flight (ToF) camera, such as those obtained with a Microsoft Kinect V2. Key advantages of this approach are that the identity of people is not disclosed, and the system can operate in low-light conditions. The automated approach developed here is inspired by cell-tracking methods as implemented in the well-known biomedical imaging software called CellProfiler. Our approach involves significant preprocessing of the depth images by a combination of adaptive center weighted median filtering and iterative inpainting. The next step is detection of each person's …

Interference Analysis And Mitigation Of Telemetry (Tm) And 4g Long-Term Evolution (Lte) Systems In Adjacent Spectrum Bands, Juan Francisco Gonzalez

Open Access Theses & Dissertations

Currently, the telecommunications, radio systems, and many other wireless services in the United States are using the spectrum from the 6 kHz to the 300 GHz frequencies. Although it may seem enough for said systems, as more users and devices are being introduced into the market, the spectrum is limiting the faster introduction of these devices and/or systems. The radio frequency spectrum is home to many transmissions, from amateur radio to cellphone applications, which all share similar frequency bands. By sharing, the number of applications can be increased in a single band, but their performance may be affected. Herein, experiments …

Improving Time-Of-Flight And Other Depth Images: Super-Resolution And Denoising Using Variational Methods, Salvador Canales Andrade

Open Access Theses & Dissertations

Depth information is a new important source of perception for machines, which allow them to have a better representation of the surroundings. The depth information provides a more precise map of the location of every object and surfaces in a space of interest in comparison with conventional cameras. Time of flight (ToF) cameras provide one of the techniques to acquire depth maps, however they produce low spatial resolution and noisy maps. This research proposes a framework to enhance and up-scale depth maps by using two different regularization terms: Total Generalized Variation (TGV) and Total Generalized Variation with a Structure Tensor …

Hybrid 3d Printing Demonstrated By Arbitrary 3d Meandering Transmission Lines, Ubaldo Robles

Open Access Theses & Dissertations

This Dissertation focuses on the automation of multi-material direct write three-dimensional (3D) manufacturing of arbitrary metal-dielectric structures. The technology was demonstrated by manufacturing 3D meandering interconnects and transmission lines (TLs). Manufacturing 3D functional electronics with multiple materials required pushing the current state of 3D printing (3DP) technology to utilize simultaneous multi-material processes combined with sophisticated slicing and bonding under one process. Multi material 3DP is known as hybrid 3DP. This research pioneered the process for producing meandering transmission lines, starting with design and manufacturing, using hybrid 3DP through micro-dispensing and fuse deposition modeling. The research starts by 3DP magnetic and …

Assessing Performance Of Detectors Of High Frequency Oscillations In Eeg Signals, Deeksha Seetharama Bhat

Open Access Theses & Dissertations

Attempts to perform epileptic seizure prediction have been made for decades, but there is no solution yet that is generally effective, though some progress in this area has been reported. Interictal epileptic spikes were considered as the only biomarkers of seizure-generating brain tissue until the recent discovery of high-frequency oscillations (HFOs) in electroencephalographic (EEG) signals, with frequency contents in the range from 80 Hz to 800 Hz. HFOs are now considered as biomarkers of epileptogenic tissue and the seizure onset zone. However, there are challenges in the definition and detection of HFO events which complicate this perspective. In studies about …

Optimization Of Neural Network Architecture For Classification Of Radar Jamming Fm Signals, Alberto Soto

Open Access Theses & Dissertations

Radar jamming signal classification is valuable when situational awareness of radar systems is sought out for timely deployment of electronic support measures. Our Thesis shows that artificial neural networks can be utilized for effective and efficient signal classification. The goal is to optimize an artificial Neural Network (NN) approach capable of distinguishing between two common radar waveforms, namely bandlimited white Gaussian jamming noise (BWGN) and the ubiquitous linearly frequency modulated (LFM) signal. This is made possible by creating a theoretical framework for NN architecture testing that leads to a high probability of detection (PD) and a low probability of false …

Compressive Vector Reconstruction: Hypothesis For Blind Image Deconvolution, Alonso Orea Amador

Open Access Theses & Dissertations

Alternative imaging devices propose to acquire and compress images simultaneously. These devices are based on the compressive sensing (CS) theory. A reduction in the measurement required for reconstruction without a post-compression sub-system allows imaging devices to become simpler, smaller, and cheaper. In this research, we propose a new algorithm to compress and reconstruct blurred images for CS imaging devices. Blur effect in images is common due to relative motion, lens, limited aperture dimensions, lack of focus, and/or atmospheric turbulence. Our intention is to compress a blurred image with CS techniques and then reconstruct a blur-free version using the proposed algorithm. …

Structural And Electrical Characterization Of Tin Oxide Resistive Switching, Arka Talukdar

Open Access Theses & Dissertations

Resistive switching in metal oxide is a phenomenon in which the metal oxide changes its resistance upon application of electric field and thus giving two states; high resistance state (HRS) and low resistance state (LRS). Many metal oxides have been investigated however very little is known about unipolar resistive switching in SnO2 though it has shown excellent resistive switching characteristics. Defects in the material play a vital role in resistive switching of the metal oxides. In this work, the role of defects in resistive switching of SnO2 are investigated in Ti/SnO2/Au structures. Two methods were used to control the concentration …

Image Data Mining For Quality Control Of Nanofiber Reinforced Piezoelectric Nanocomposites Based On Sem Images, Zhonghua Hu

Open Access Theses & Dissertations

Recently, portable and wireless nano-scaled devices have been widely used in environmental monitoring, medical implants, defense technology, industrial safety, and personal electronics, such as the nanowire-based gas and chemical sensors and programmable nanowire circuit for nano-processors. There has been an increasing demand for high energy density capacitors that can be engineered for various applications in advanced devices. In it, piezoelectric nanofiber materials play critical role in producing new products. A piezo-ceramic polymer composite contains a polymer of high dielectric strength and high permittivity ceramic inclusions, making it well suited as a high energy density capacitor. Furthermore, the research shows that …

Classification Of Radar Jammer Fm Signals Using A Neural Network Approach, Ariadna Estefania Mendoza

Open Access Theses & Dissertations

A Neural Network (NN) used to classify radar signals is proposed for the purpose of military survivability and lethality analysis. The goal of the NN is to correctly differentiate Frequency-Modulated (FM) signals from Additive White Gaussian Noise (AWGN) using limited signal pre-processing. The FM signals used to test the NN approach are the linear or chirp FM and the power-law FM. Preliminary simulations using the moments of the signals in the time and frequency domain yielded better results in the frequency domain, suggesting that time domain training would not be as effective frequency domain training. To test this hypoThesis, we …

Safety Airway For Small Unmanned Aerial Vehicles Using A Gas Particles Behavior Analogy, Pablo Rangel

Open Access Theses & Dissertations

The United States Federal Aviation Administration (FAA) implemented the Part 107 legislation to allow the flight of Unmanned Aerial Vehicles (UAV) for commercial use (i.e. package deliveries, power transmission line inspections, etc.) in the National Airspace System (NAS). As a consequence of the newly introduced rules, there is an increased risk for accidents involving injured bystanders or damaged to property. The work within this document defines a UAV to UAV safety distance model that acts as a range sensor enabled "elastic bubble". The length of the UAV safety bubble contracts and expands upon changing airway wind speed conditions. It also …

Bragg Gratings In Polarization Maintaining Optical Fiber As Three Dimensional Strain Sensor, Joel Quintana

Open Access Theses & Dissertations

Fiber-Bragg Gratings (FBG) for Structural Health Monitoring (SHM) have been studied extensively as they offer electrically passive operation, electromagnetic interference (EMI) immunity, high sensitivity and multiplexing as compared to conventional electric strain sensors. FBG sensors written within polarization maintaining (PM) optical fiber offer ad- ditional dimensions of strain measurement, greatly reducing the number of sensors needed to properly monitor a structure. This reduction however, adds complexity to the dis- crimination of the sensorâ??s optical response to its corresponding applied strains. This Dissertation defines the set of algorithms needed to measure planar strain using PM-FBGs exclusively. It defines the minimum number …

Organic-Inorganic Graphite And Transition Metal Dichalcogenide Based Composites For 3d Printing, Jorge Alfredo Catalan Gonzalez

Open Access Theses & Dissertations

This project was multipronged to help fuse together topics of additive manufacturing and two-dimensional (2D) layered materials, and studying the mechanical and electrical properties of the composites produced. The composites are made from the thermoplastic polymer acting as a matrix and the graphite and 2D transition metal dichalcogenides (TMDs) serving as the filler or reinforcement. Different concentrations of TMD's were added to the matrix to study the effect of composition on the mechanical and electrical properties. To shed insights into the mechanical properties, test coupons were produced as "dog bone" structures for tensile testing using the ASTM D638 type 5 …

Advances In Chemical Vapor Deposition Growth Of Molybdenum Disulfide For Photodetectors And Flexible Electronics, Carlos Francisco De Anda Orea

Open Access Theses & Dissertations

The conversion of light into electrical signals is at the basis of technologies that affect our daily lives. Applications, including video imaging, optical communications, biomedical imaging, security, night-vision, gas sensing and motion detection have reached a high level of maturity due to the development of high-performance materials, large-scale production, and integration technologies. Currently conventional photodetectors made of Silicon (Si) or III-V compounds are about to reach their maximum efficiency, and every time it is harder to get a noticeable improvement in performance of sensors based on these materials, not to mention the complicated fabrication methods to achieve just a few …

Automatic Patch Classification And Diffusion In Adaptive, Luis Alonso Ponce

Open Access Theses & Dissertations

Multi-Frame image restoration is a form of Super-Resolution (SR) which consists of combining multiple Low-Resolution (LR) images in order to reconstruct a single High Resolution (HR) image. In this Thesis we improved a spatially-adaptive SR scheme, based on the framework of Optimal Recovery (OR), whereby the block-by-block processing is done based on the properties of the corresponding local LR image data patches. The bandwidth parameter is adapted based on the local variance of each corresponding block from all LR images that contribute to the HR image block to be reconstructed. Also, an optimal regularization parameter needs to be chosen for …

Synthesis, Device Fabrication, And Characterization Of Two-Dimensional Molybdenum Disulfide, Gustavo Alberto Lara Saenz

Open Access Theses & Dissertations

The miniaturization of electronic devices according to Moore's Law has been propelled by the continuous demand for faster and smaller devices which continue to advance technology. One recent contribution to this trend was the isolation and characterization of one atom thick of graphite, known as graphene, which led to the Nobel Prize in physics in 2010 being awarded to Andre Geim and Konstantin Novoselov. Graphene and its related nanocarbon derivatives have exceptional mechanical, thermal, optical and electronic properties, making them a potential candidate for electronics and optoelectronics applications. However, this material has no intrinsic bandgap and complicated processes are required …

Touch And Step Potential Analysis At 23.9kv To 4.16kv & 13.8kv To 4.16kv Distribution Substations With Pad-Mounted Transformers, Floating Grounds, And Other Exposed Ungrounded Metal Bodies Using Winigs, David Guillermo Guzman

Open Access Theses & Dissertations

An electrical substation is composed of various subsystems that allow for the effective and safe operation of the power grid. One of the subsystems integrating a conventional substation is defined as the ground grid system. This system allows for the effective operation of the power grid and all the electrical equipment connected to it by providing a ground potential reference, commonly known as the system ground. In addition, the ground grid system provides safety to the workers and the public transiting inside or living nearby a substation by reducing the step and touch potential (or voltage) levels present during a …

G-Code Generation For Multi-Process 3d Printing, Callum Peter Bailey

Open Access Theses & Dissertations

Since the inception of stereolithography in the 1980s, interest in 3D printing has exploded, with desktop 3D printers now commercially accessible to the general public. In recent years, next-generation multifunctional technologies have been developed, which combine 3D printing with other technologies such as wire embedding, foil embedding, CNC machining, and robotic component placement, enabling complex parts to be made on a single multifunctional machine.

However, the complexity of these integrated processes exceeds the capabilities of established design tools. To this end, this Thesis aims to develop a multi-functional design solution that can automatically generate final control code for next-generation multifunctional …

A Spatially Variant Metamaterial Design Process For Transformation Electromagnetic Devices, Eric Alan Berry

Open Access Theses & Dissertations

A technique for the implementation of devices designed using transformation optics (TO) is presented using metamaterial elements arranged using spatially variant lattices. A description of transformation optics, including the design of arbitrarily shaped devices by solving Laplace's equation numerically, is discussed. Analysis of a variety of metamaterial unit cells using frequency sweeps of the unit cells with the resulting permittivity and permeability values. Metamaterial unit cells are also analyzed by the scaling of all the features of the metamaterial elements in the unit cell and calculating the permittivity and permeability. Finite- difference time domain (FDTD) and finite-difference frequency domain (FDFD) …

Digital Processes And Characterization For Fabricating 3d Rf Devices, Harvey Hing Tsang

Open Access Theses & Dissertations

In this work, co-planar waveguides (CPW) are fabricated and characterized with low temperature 3D printed materials for flexible electronic applications. Laser processing is introduced to reduce heating and cooling times for curing and subtractive manufacturing. CPWs are optimized by varying printing resolution, adjusting curing conditions and shaping conductor profile with a pico-laser. By using acrylonitrile butadiene styrene (ABS) as substrate material and Dupont CB028 as conductive material, a high S21 and low S11 CPW is fabricated. Optimized direct write methods are dispensed onto 3D complex structures to move away from 2.5D style printing and move into true 3D printed antenna …

Cdte Doped With Zn Grown On Si(111) And Si(211) Using The Closed Space Sublimation Method, Jose Alberto Valdez

Open Access Theses & Dissertations

Cadmium telluride (CdTe) doped with zinc (Zn) has been used for the fabrication of X-ray imaging devices. CdTe allows the device to have the same image quality at a lower X-ray dose. When silicon is used as a substrate for CdTe growth, this reduces the cost and allows the readout circuitry to be fabricated on the same substrate. However, material quality and device performance needs to be addressed since the lattice parameters of CdTe (6.482 Å) and Si (5.431 Å) result in a 19% lattice mismatch.

In this work, CdTe doped with Zn is deposited on Si (211) and Si …

Design And Evaluation Of The Impact Of A Multi-Agent Control System (Framework) Applied To A Social Setting, Perez Antonio Perez

Open Access Theses & Dissertations

The objective of this research is to design and analyze the performance of a new mechanism to improve the advising of students in a nontraditional environment. This nontraditional environment includes: a minority serving, commuter campus with a high percentage of transfer students. Specifically, these demographics are unable to keep a tightly controlled cohort of students flowing through to the completion of the curriculum. Students in these circumstances usually have varied course loads and competing priorities due to family and financial needs or other societal responsibilities. Therefore, there is a need for an individualized approach to advising.

University administrations face challenges …

Adaptive Switched Capacitor Voltage Boost For Thermoelectric Generation, Rene A. Brito

Open Access Theses & Dissertations

Thermoelectric generators (TEG) and other forms of energy harvesting often provide voltages that are not directly usable by traditional electronics as levels are too low from the TEG. While increasing the number of thermoelectric elements can ultimately increase the power output, there is a tradeoff between size and power. By implementing charge pumps, a proposed circuit technique is described that can boost the TEG output to levels that can be used for energy harvesting applications. Current voltage boost circuits for TEGs simply boost a voltage by a set amount. The proposed circuit consists of an analog chip, to provide several …

Information Entropy Measures Applied To Hierarchial Complex Technical And Socio-Technical Systems, Satya Aditya Akundi

Open Access Theses & Dissertations

A significant increase of Systems-of-Systems (SoS) is currently observed in the social and technical domains. With increasing constituent components, Systems of Systems are becoming larger and more complex. Recent research efforts have highlighted the importance of identifying innovative statistical approaches for analyzing complex systems to better understand how they work. This research is aimed towards developing an Information Entropy based framework to analyze complex technical and social systems. Entropy in terms of information theory can be seen as the expected amount of information observed in an event. A parallel can be drawn between information entropy and system complexity, where, as …