Electrical and Electronics Commons^™

Charge Mitigation Technologies For Aircraft Platforms, Mitchell L. Rudy

Theses and Dissertations

Research into ion-based advanced propulsion systems, such as air-breathing Hall effect thrusters on high-velocity aircraft and ion-propelled thrusters on spacecraft, necessitates addressing accompanying residual electric charge accumulation on the ungrounded flight platform. An experimental testbed was constructed to assess charge mitigation technologies and their effectiveness on aircraft. A Van de Graaff generator provided static charge accumulation levels exceeding a megavolt when combined with a high voltage direct current source generator. This research attached an isolated airfoil structure to the Van de Graaff generator's lower terminal to measure the induced leakage current under various applied environmental conditions, including up to three …

Robust Scandium Aluminum Nitride Mems Resonators For L Band Operation In Orbital Environments, Israel W. Dunk

Theses and Dissertations

This thesis investigates AlN alloyed with scandium in a variety of resonator architectures including WEM, overtone WEM, LEM, and SAW that have the potential to achieve high levels of electrical performance and environmental robustness. SAW resonators operating near 370 MHz are fabricated on polycrystalline Sc_.37Al_.63N, and AlN with the resulting devices compared and conclusions drawn as to the merits of each material. The design and fabrication of SAW devices is discussed in detail, with the operating characteristics of these resonators then tested both electrically and mechanically. Mechanical characterisation includes analysis of vibration and shock effects on …

Surface Defect Detection In Aircraft Skin & Visual Navigation Based On Forced Feature Selection Through Segmentation, Tyler B. Hussey

Theses and Dissertations

Visual inspection of aircraft skin for surface defects is an area of maintenance that is particularly intensive for time and manpower. One novel way to combat this problem is through the use of computer vision and the advent of Artificial Neural Networks (ANN), or more specifically, semantic segmentation via Convolutional Neural Networks (CNN). The research in the paper explores the use of semantic segmentation of aerial imagery as a way to force feature selection onto key areas of an image that might be more likely to correspond under seasonal variations. Utilizing feature selection and matching on the masked aerial image …

Supporting Space Domain Awareness Through The Development And Analysis Of Space Object Detection Algorithms Employed By Ground-Based Telescopes, Connor A. Paw

Theses and Dissertations

Detection algorithms are instrumental in maintaining space domain awareness, specifically in the observation, monitoring, and categorization of unknown space objects. State of the art detection algorithms utilize a matched filter or a spatial correlator on long exposure image data to make pixel-wise detection decisions. This thesis investigates the advantages and practical potential of two different post-processing detection algorithms that can be employed by ground-based telescopes. The first algorithm explored is based on a long exposure Fourier domain processing technique, while the second is centered around frame selection from a series of short exposure images. The results of the experiments performed …

A Feedback-Based Pneumatic Compression System For Effective Lymphedema Management, Mohammad Imrul Kayes

LSU Master's Theses

Bioimpedance analysis (BIA) is a method of detecting lymphedema- a debilitating medical condition involving swelling of the extremities. Pneumatic compression devices are frequently used in the compression treatment of lymphedema. Although existing compression technology provides relief of symptoms, it has limitations in terms of ease-of-use, portability, and monitoring of treatment progress. Currently, there are no BIA analyzers in the market that run on a low-power microcontroller and a rechargeable battery. Moreover, no such device currently exists that integrate the BIA analysis with pneumatic compression system to offer a feedback-based solution for lymphedema treatment. This work represents the first steps towards …

A Pi Based Coordinated Maximum Power Point Tracking Controller For Grid Connected Photovoltaic System, Md Haidar Islam

Student Works (2020-2029)

The global demand for electric energy has continuously increased over the last few decades. Photovoltaic (PV) sources are predicted to become one of the biggest contributors to electricity generation among all renewable energy generation candidates by 2040. The photovoltaic system a renewable energy source that has attracted the attention of researchers in recent years. The power output of a photovoltaic system has a complex dependence on varying environmental conditions such as solar irradiation and ambient temperature which cannot be controlled, thereby making the current versus voltage (I-V) and power versus voltage (P-V) characteristics of photovoltaic arrays nonlinear. Therefore, maximum power …

Investigation Of The Interfacial Energy Level Within Organic Semiconducting Devices, Wong Wah Seng

Student Works (2020-2029)

This main goal of this research is investigating the interfacial energy level of organic semiconducting devices by correlated to the devices performance as well as physical/chemical change in the blended/mixed organic semiconductor system. The first project reported the high efficiency extra warm white organic light emitting diodes (WOLEDs) by blending tris(4-carbazoyl-9-ylphenyl)amine (TcTa) to poly(vinylcarbazole) (PVK). The hole current for PVK:TcTa (60:40) increased by one order of magnitude in hole only device, but the current efficiency of WOLEDs improved only by 7% compared to pristine PVK. Using Ultraviolet photoelectron spectroscopy (UPS), it was discovered the hole injection barrier between poly(3,4-ethylenedioxythiophene) polystyrene …

Research Of Focl Parameters In The Range Of Positive Temperatures, Dilmurod Davronbekov, Zafar Khakimov

Bulletin of TUIT: Management and Communication Technologies

This article studies the parameters of fiber-optic communication lines (FOCL) in the temperature range. For research, a climatic unit has been developed that allows a wide temperature range for testing (from -90°C to + 90°C) and an experimental complex for investigating the stability of optical parameters of a fiber-optic cable with temperature changes in the range from + 18°C to + 76°C. A technology of sequential switching of optical fibers of a fiber-optic cable by means of welding is proposed, thanks to which the constructive problem of placing a long optical fiber in a limited volume of a heat chamber …

Dual-Band Doherty Power Amplifier With The Improvement Of Reactance Compensation Technique For Lte Frequency Operations, Yu Li Ming

Student Works (2020-2029)

A dual-band selection of Doherty power amplifier employing a Reactance Compensation Technique (RCT) with Gallium Nitride High-Electron-Mobility-Transistor (GaN HEMT) technology is presented. In this dissertation, the focus has been given to the design power amplifier in Doherty configuration, where it can operate at dual-band frequency and enhanced performances at 6 dB back-off from saturation power. This project applied lossy matching circuit for the input matching network and incorporated the primary motivation of using RCT and third harmonic tuning for the output matching network. The DPA designed can achieve satisfying results for the frequency of 0.8 and 2.1 GHz. The implementation …

Characterization Of Spatial-Mode Properties In Few-Mode Fiber Bragg Gratings And Its Applications, Muhammad Khairol Annuar Zaini

Student Works (2020-2029)

Recently, few-mode fiber (FMF) has gained much research attention compared to single mode fiber (SMF) due to its capability to overcome the capacity limit. FMF based fiber sensors have many distinctive advantages such as cost efficiency, great sensitivity, and have the ability to employ the spatial dimension for multi-parameter sensing with discrimination capability. In this work, an analytical model has been proposed to investigate the relationship of the resonant wavelength shift of a few-mode FBG (FMFBG) to the axial stress of the FMF. By applying the proposed model, the axial stress of an FMFs was determined. Besides, the polariscopic technique …

Synthesis And Characterization Of Perovskite-Based Materials For Memory Device Application, Gregory Thien Soon How

Student Works (2020-2029)

This project aims to study the resistive switching behaviour in memory devices using perovskites-based structures. A hybrid organic-inorganic lead halide perovskite was studied in this project, specifically methylammonium lead triiodide, CH3NH3PbI3 or MAPbI3 perovskite. The effect of the various counter electrodes in MAPbI3 perovskite was investigated by fabricating MAPbI3 perovskite on Indium Tin Oxide (ITO). Three commonly used electrodes which are Aluminium (Al), Silver (Ag), and Gold (Au) were thermally evaporated on top of the MAPbI3 perovskite layer. It was found that the ITO/MAPbI3/Al exhibits Resistive Random Access Memory (ReRAM) behaviour with SET voltage (VSET) of 4.5 V and RESET …

Deep Learning For Task-Based Image Quality Assessment In Medical Imaging, Weimin Zhou

McKelvey School of Engineering Graduate Student Theses & Dissertations

It has been advocated to use objective measures of image quality (IQ) for assessing and optimizing medical imaging systems. Objective measures of IQ quantify the performance of an observer at a specific diagnostic task. Binary signal detection tasks and joint signal detection and localization (detection-localization) tasks are commonly considered in medical imaging. When optimizing imaging systems for binary signal detection tasks, the performance of the Bayesian Ideal Observer (IO) has been advocated for use as a figure-of-merit (FOM). The IO maximizes the observer performance that is summarized by the receiver operating characteristic (ROC) curve. When signal detection-localization tasks are considered, …

Holistic Control For Cyber-Physical Systems, Yehan Ma

McKelvey School of Engineering Graduate Student Theses & Dissertations

The Industrial Internet of Things (IIoT) are transforming industries through emerging technologies such as wireless networks, edge computing, and machine learning. However, IIoT technologies are not ready for control systems for industrial automation that demands control performance of physical processes, resiliency to both cyber and physical disturbances, and energy efficiency. To meet the challenges of IIoT-driven control, we propose holistic control as a cyber-physical system (CPS) approach to next-generation industrial automation systems. In contrast to traditional industrial automation systems where computing, communication, and control are managed in isolation, holistic control orchestrates the management of cyber platforms (networks and computing platforms) …

Constructing And Analyzing Neural Network Dynamics For Information Objectives And Working Memory, Elham Ghazizadeh Ahsaei

McKelvey School of Engineering Graduate Student Theses & Dissertations

Creation of quantitative models of neural functions and discovery of underlying principles of how neural circuits learn and compute are long-standing challenges in the field of neuroscience. In this work, we blend ideas from computational neuroscience, information and control theories with machine learning to shed light on how certain key functions are encoded through the dynamics of neural circuits. In this regard, we pursue the ‘top-down’ modeling approach of engineering neuroscience to relate brain functions to basic generative dynamical mechanisms. Our approach encapsulates two distinct paradigms in which ‘function’ is understood. In the first part of this research, we explore …

Theory, Design And Implementation Of Energy-Efficient Biotelemetry Using Ultrasound Imaging, Sri Harsha Kondapalli

McKelvey School of Engineering Graduate Student Theses & Dissertations

This dissertation investigates the fundamental limits of energy dissipation in establishing a communication link with implantable medical devices using ultrasound imaging-based biotelemetry.

Ultrasound imaging technology has undergone a revolution during the last decade due to two primary innovations: advances in ultrasonic transducers that can operate over a broad range of frequencies and progresses in high-speed, high-resolution analog-to-digital converters and signal processors. Existing clinical and FDA approved bench-top ultrasound systems cangenerate real-time high-resolution images at frame rates as high as 10000 frames per second. On the other end of the spectrum, portable and hand-held ultrasound systems can generate high-speed real-time scans, …

Neural Dynamics, Adaptive Computations, And Sensory Invariance In An Olfactory System, Srinath Nizampatnam

McKelvey School of Engineering Graduate Student Theses & Dissertations

Sensory stimuli evoke spiking activities that are patterned across neurons and time in the early processing stages of olfactory systems. What features of these spatiotemporal neural response patterns encode stimulus-specific information (i.e. ‘neural code’), and how they are translated to generate behavioral output are fundamental questions in systems neuroscience. The objective of this dissertation is to examine this issue in the locust olfactory system. In the locust antennal lobe (analogous to the vertebrate olfactory bulb), a neural circuit directly downstream to the olfactory sensory neurons, even simple stimuli evoke neural responses that are complex and dynamic. We found each odorant …

Machine Learning Morphisms: A Framework For Designing And Analyzing Machine Learning Work Ows, Applied To Separability, Error Bounds, And 30-Day Hospital Readmissions, Eric Zenon Cawi

McKelvey School of Engineering Graduate Student Theses & Dissertations

A machine learning workflow is the sequence of tasks necessary to implement a machine learning application, including data collection, preprocessing, feature engineering, exploratory analysis, and model training/selection. In this dissertation we propose the Machine Learning Morphism (MLM) as a mathematical framework to describe the tasks in a workflow. The MLM is a tuple consisting of: Input Space, Output Space, Learning Morphism, Parameter Prior, Empirical Risk Function. This contains the information necessary to learn the parameters of the learning morphism, which represents a workflow task. In chapter 1, we give a short review of typical tasks present in a workflow, as …

Ultrafast Thermal Modification Of Strong Coupling In An Organic Microcavity, Bin Liu, Vinod M. Menon, Matthew Y. Sfeir

Advanced Science Research Center

There is growing interest in using strongly coupled organic microcavities to tune molecular dynamics, including the electronic and vibrational properties of molecules. However, very little attention has been paid to the utility of cavity polaritons as sensors for out-of-equilibrium phenomena, including thermal excitations. Here, we demonstrate that non-resonant infrared excitation of an organic microcavity system induces a transient response in the visible spectral range near the cavity polariton resonances. We show how these optical responses can be understood in terms of ultrafast heating of electrons in the metal cavity mirror, which modifies the effective refractive index and subsequently the strong …

Asset Management Framework For The United States Army Corps Of Engineers Lock And Dam Electrical Equipment, Megan Elizabeth Bates

Theses, Dissertations and Capstones

The focus of this thesis is to design an efficient and effective preventative maintenance program for the electrical equipment that the United States Army Corps of Engineers (USACE) operates at the locks and dams. This thesis presents the concept of asset management and designs a framework to manage the electrical assets at USACE. The methodology was tested, and the results validated the framework proposed in this thesis. The framework was tested on two separate projects and the results were the same optimized strategies, which shows that the framework is robust and can be implemented into each project and can give …

A Zugunruhe Data Collection System Using Passive Infrared Sensors, Ryan Terry, Luis E. Ramirez, Carol Carrera, Abigail Kimmitt, Kira Delmore, Ana Goulart

Pursue: Undergraduate Research Journal

When engineers and biologists work together, there is a lot to learn on both sides. For instance, our work introduced us to zugunruhe, which is a German word that means “unrest”. It is used in the context of migratory birds, as they become restless at night, inside their cages, during their migratory period. When does zugunruhe start? It usually starts when the weather becomes cold and the days shorter, but it varies for different bird species. Moreover, global warming has caused changes in zungunruhe’s timing, which made it even harder to predict. Another question is about genetics: is …