Electrical and Computer Engineering Commons^™

Study Of A Multi-Agent Containment Problem Under Communication Constraints And Defense From Malicious Agents, Braulio Mora

Mechanical and Aerospace Engineering Theses - Archive

This thesis investigates a multi-agent containment problem where a fast evader, moving at a constant speed and heading, attempts to escape a circular containment region. A team of slow pursuers possess a nonzero capture radius and seek to capture the evader before escape. The research addresses two primary scenarios: one involving the team of pursuers, with no communication network, being constrained to the edge of the containment region, and the second involving a team of pursuers, with a communication network, not being constrained to the edge of the containment region. Both scenarios study the influence of malicious agents in the …

Nonlinear Guidance And Control Of Unmanned Aerial Manipulators For Delivering A Payload On A Moving Platform, Ravi Gyawali

Mechanical and Aerospace Engineering Theses - Archive

Unmanned Aerial manipulators (UAMs) are a class of Unmanned Aerial Vehicles (UAVs) equipped with a manipulator. By combining the aerial mobility of a UAV with a manipulator's dexterity, these hybrid systems can perform a wide range of complex tasks while reducing risks and costs. As a result, they are increasingly being utilized for military, industrial, and agricultural applications.

The thesis presents a novel approach for a multi-UAM system to collaboratively deliver a payload on a stationary or maneuvering platform. A sliding-mode-based guidance law, sourced from existing literature, is integrated with a combined control technique for the UAVs and their respective …

Electophorectic Deposition For Novel Nanodecorated Electrodes Towards Thermally Charging Supercapacitor (Tcsc), Ashish Thakur

Mechanical and Aerospace Engineering Theses - Archive

Thermally Self-Charging Supercapacitors (TSCS) are a promising new technology that can harvest waste heat to produce electrical energy. The Soret effect is exploited wherein ion separation due a temperature gradient leads to a potential difference. Here, we use electrophoretic deposition (EPD), a room-temperature, scalable, universal technique, to obtain CNT decorated electrodes for fabrication of such TSCS devices with ionic liquid electrolyte. We further show that precise control over deposition parameters can be used for optimization of TSCS performance metrics. TSCS devices were tested by several characterization standards, indicating the superior performance of nanodecorated electrodes obtained by EPD.

Enhancing Electromigration Reliability In Solder Interconnects Through Microstructure Control And Thermomechanical Failure Mechanisms In Thin Metal Lines Under Surge Current Conditions, Hariram Mohanram

Material Science and Engineering Dissertations - Archive

The relentless miniaturization of semiconductor devices has intensified reliability challenges in electronic packaging, particularly for solder interconnects and thin metal lines. This dissertation investigates two critical failure mechanisms—electromigration (EM) and thermomechanical fatigue (TMF)—and explores strategies to mitigate these effects. Electromigration, driven by high-density current-induced atomic migration, significantly impacts solder interconnects. This study examines the role of Under-Bump Metallization (UBM) and solder microstructure in improving EM reliability. Findings reveal that thicker UBMs delay void nucleation and enhance EM resistance, while the absence of UBM leads to failure through vertical void propagation. Additionally, grain orientation, particularly the c-axis alignment in Sn grains, …

A Comprehensive Exploration Of Fundamental And Experimental Characteristics Of Nanophotonic Metasurfaces, Nasrin Razmjooei

Electrical Engineering Dissertations - Archive

The advent of diffraction gratings with periodic unit cells has led to numerous advancements in theoretical studies and practical applications. Recently, these structures have been recognized as subsets of “meta-surfaces” or “meta-materials”, employing periodically aligned features at the wavelength scale to manipulate electromagnetic wave properties for diverse applications. This manipulation extends to controlling amplitude, phase, spectral distribution, polarization state, and the local mode structure of light across various spectral expressions. A significant characteristic of these metasurfaces is their ability to couple incident light to laterally propagating leaky Bloch modes in the subwavelength regime, resulting in resonance at specific wavelengths known …

A Wearable Sensing System For High-Speed Interface Of Wide Range Electrochemical Sensor Array, Shanthala Lakshminarayana

Electrical Engineering Dissertations - Archive

Electrochemical sensing systems have emerged as indispensable tools in various fields due to their remarkable sensitivity, selectivity, and versatility. They play a pivotal role in modern research, industry, environmental monitoring, and healthcare devices. In environmental monitoring, these systems are deployed for detecting pollutants, heavy metals, and toxic gases, facilitating real-time monitoring, and ensuring environmental safety. Whereas, in the biomedical field, electrochemical sensing systems play a crucial role in diagnosing diseases, monitoring biomarkers etc, thereby revolutionizing healthcare practices.

Cost-effective wearable electrochemical sensing devices are significant for democratizing healthcare and improving public health outcomes. These devices enable continuous monitoring of physiological parameters, …

Pulsed Dielectric Breakdown And Permittivity Characterization Of Composite Solid Insulators In Pulsed Power Systems, Shawn T. Scoggin

Electrical Engineering Dissertations - Archive

In high voltage pulsed power systems, liquids and gases are often used as insulating materials because they offer high breakdown strengths, conform around complex geometries, and are self-healing, but they can introduce significant engineering challenges and restrictions when it comes to implementing them. Solid dielectrics can be desirable for improving the maintenance requirements, shelf life, and power/energy density metrics associated with insulating high voltage pulsed power systems, however they possess design challenges of their own. Solid dielectrics are not self-healing and can be difficult to manufacture, especially around complex geometries. Epoxy dielectrics are of high interest because of their naturally …

Exploring Machine Learning Techniques For Embedded Hardware, Neel R. Vora

Computer Science and Engineering Theses - Archive

This thesis delves into the intricate symbiosis between machine learning (ML) methodologies and embedded hardware systems, with a primary focus on augmenting efficiency and real-time processing capabilities across diverse application domains. It confronts the formidable challenge of deploying sophisticated ML algorithms on resource-constrained embedded hardware, aiming not only to optimize performance but also to minimize energy consumption. Innovative strategies are explored to tailor ML models for streamlined execution on embedded platforms, with validation conducted across various real-world application domains. Notable contributions include the development of a deep-learning framework leveraging a variational autoencoder (VAE) for compressing physiological signals from wearables while …

Development And Application Of Guided Mode Resonance Biosensor Platforms For Highly Sensitive And Real-Time Cell Killing Assays, Seyedmohsen Vaziri

Electrical Engineering Dissertations - Archive

In this work, we developed and investigated the cancer cell killing efficacy of different instances using real-time high-sensitivity measurements facilitated by Guided-Mode Resonance (GMR) sensors. The GMR biosensor technology detects shifts in the spectral peak caused by changes in the refractive index of the surrounding medium, offering a label-free method for monitoring cellular events.

A549 cell line wild type and HER2 knockout (lung cancer cells) were exposed to different concentrations of Triton X-100 and ADC (Herceptin with αHFc-CL-DMDM). The GMR-based cell killing assay demonstrated exceptional sensitivity and specificity, with shifts in wavelength exhibiting a robust correlation with cell viability and …

Li-Ion Battery Resistance During External Short Circuits And Cyclic Ageing, Kaynat Zia

Electrical Engineering Dissertations - Archive

External short circuit testing (ESCT) is one of the many steps towards ensuring lithium-ion (Li-ion) batteries are safe for different applications. The nature of testing is sensitive due to the concern of safety and data integrity. Great care and planning must be done before conducting these tests. Bouncing in recorded data is observed in literatures with high sampling rates due to switching and moving mechanical parts. This impacts the estimation accuracy of battery internal parameter values especially the effective ohmic resistance (Ro). This dissertation proposes a zero bouncing circuit design to eliminate this problem. Multi-rate Pulse Discharge Testing (MPDT) is …

All-Optical Signal Processing With Fiber-Based Parametric Wavelength Converters, Cheng Guo

Electrical Engineering Dissertations - Archive

The optical signal degradation by optical amplifier noise set the fundamental limit of link reach in the fiber-optics networks. The industrial solution is to use the optical-electrical-optical (OEO) regenerator to clean up the noise at the expense of high-speed electronics and extra cost of laser and photodetectors. All-optical signal processing, enabled by nonlinear optics and optical fiber, intrinsically provides 2-order of magnitude higher processing bandwidth and seamless interface to fiber communication channels. However, there is no robust phase-preserving regenerator that has been experimentally demonstrated without sophisticated polarization tuning and without instable interferometric structure. In this project, we explore the applications …

Analysis Of Noise Sources In Avalanche Region Of Reverse Biased P-N Junctions, Md Sakiul Islam Sudman

Electrical Engineering Theses - Archive

There is a need to understand the physical mechanisms for excess noise factor (F) in avalanche diodes for all regions of operation. The current classical theory accounts for F only for low carrier multiplication where single carrier injection starts the avalanche process. Our model fits the white noise exhibited by reverse-biased avalanche diodes in the entire operation region of four orders of current magnitude. In this sense, it is a first. The measured noise data was provided by Texas Instruments. We fitted the measured noise components with the calculated noise components where carrier multiplication takes place. The least …

Neural Net Estimation Of Discriminants Posterior Probability Vector, Harshvardhan Harshvardhan

Electrical Engineering Theses - Archive

Interpreting multi-layer perceptron (MLP) classifier outputs as posterior probabilities is a well-established practice in machine learning and is supported in the literature. However, several authors point out that MLP outputs are very poor estimates of the posterior probabilities. This is demonstrated for classifiers with and without nonlinear output activation. Achieving this reliability depends on key factors such as model complexity, sufficient training data availability, and optimization techniques' effectiveness. In practice, these requirements are not met, resulting in suboptimal probability estimates. Our approach introduces an innovative method based on the softmax output. The method aim to refine MLP discriminants into more …

Semiconductor Photonic Crystal Surface Emitting Lasers For High Power, High Brightness And High Speed Applications, Chhabindra Gautam

Electrical Engineering Dissertations - Archive

Photonic Crystal Surface Emitting Laser (PCSEL) is the promising third generation semiconductor laser technology as it addresses the challenges of the conventional semiconductor lasers (EEL/VCSEL) by providing single mode high power output with good beam quality (thus high brightness). The large area in plane coupling resulting from the multiple Bragg’s diffraction conditions in the periodic 2D photonic crystal cavities in the lasing cladding region leads to single mode operation over very large area. By model design engineering, such in plane lasing cavity can leak the light out of the plane, which result in surface emission. The ability to scale the …

Learning And Control For Complex Multiagent Systems, Vrushabh S. Donge

Electrical Engineering Dissertations - Archive

Complex multiagent systems (MASs) are pervasive in various fields, from power system networks, and autonomous robotics to traffic management, where groups of agents interact to achieve collective objectives. Effective coordination and control of such systems pose significant challenges due to their inherent complexity and the need for adaptive, efficient strategies. This dissertation explores combining data-driven approaches, reinforcement learning (RL), and control theory to address these challenges. We present novel methodologies for learning and controlling complex MASs, emphasizing the development of adaptive algorithms that can autonomously adapt to dynamic environments, collaborate with other agents, and optimize system-wide performance. Our findings offer …

Applications Of The Guided-Mode Resonance Sensor In Multiparametric, Transmissive, And Picomolar Regimes, Joseph Anthony Buchanan-Vega

Electrical Engineering Dissertations - Archive

Guided-mode resonance (GMR) sensors are developed and implemented for multiparametric label-free sensing, transmission sensing, enhanced reflection sensing, and low analyte concentration sensing; these are the topics presented in this work. The complete biosensor – capable of label-free multiparametric data collection – is designed, fabricated, and implemented. Multiparametric data collection has previously been relegated to one variable on the sensor surface and one bulk media variable. We use a lookup table and the novel application of an inversion algorithm to simultaneously determine two variables on the sensor surface and one bulk media variable. Multiparametric data sets are required to monitor multiple …

Optimal Sizing And Safe Management Of Lithium-Ion Batteries In High Voltage Power Systems, Hayden Lee Atchison

Electrical Engineering Dissertations - Archive

Lithium-ion batteries have gained widespread use in various applications, but safety challenges persist due to errors in assembly and faulty electronics management. Ensuring safety and reliable operation in large batteries containing numerous series/parallel cells demand innovative monitoring technologies. Elevated temperatures resulting from normal or abnormal operation are a major cause of battery failure, necessitating effective temperature monitoring techniques. Similarly, abnormal stress/strain signatures offer valuable diagnostic information. In the study discussed here, the application of a Optical Distributed Sensor Interrogator (ODiSI) employing high-definition fiber optic sensors (HD-FOS) for measuring surface temperature and case deformation of 18650 cells under normal and abnormal …

Hardware In The Loop Test Stand For Battery Management System Validation In Shipboard Controls, Cole Dawson Tschritter

Electrical Engineering Dissertations - Archive

ABSTRACT: Traditionally, large-scale power systems have relied on power generation always exceeding the total load demand. Though this is most often the case, there are rare occurrences where failures in the generation, distribution, or even planning, that have led to situations where load demand quickly surpasses the generation capacity. In such cases, uncontrolled shedding of loads occurs, leading to brownouts or blackouts that can have catastrophic impact to both people and property. Advanced architectures, such as microgrids, offer a variety of improvements that are aimed at mitigating or even preventing these failures. Improvements include distributed power generation, active source and …

Model Optimization And Applications In Deep Learning, Chengchen Mao

Electrical Engineering Dissertations - Archive

ABSTRACT: Machine learning refers to a machine or an algorithm that draws experience from data. A certain pattern is found to build a model, which is used to solve real problems. Deep learning, an important branch and extension of machine learning, employs a neural network structure containing multiple hidden layers. It learns critical features of the data by combining lower-level features to form more abstract higher-level representations of attribute categories or features. In this dissertation, deep learning network models were applied to sense-through-foliage target detection and extended with Rake structure. The deep learning network models had a large number of …

Environment, Communication And Decision For Multiagent Systems, Lu Zhao

Electrical Engineering Dissertations - Archive

ABSTRACT: Multiagent systems (MAS) are ubiquitous in modern systems and have found broad applications, such as in intelligent transportation systems (ITS). Environment, communication and decision are among the essential components of MAS. The realistic environment in which MAS operates is usually stochastic, and its modeling, identification and estimation are important to consider. The communication in MAS is also critical for decisions. For example, in ITS, to improve travel efficiency and reduce traffic accidents, scheduling schemes for Vehicle-to-Everything (V2X) communication need to be developed. MAS decisions also need to be robust to uncertainties. For example, in mixed-traffic autonomous driving, the decisions …

Utilizing Data Analytics On Single-Phase Ac Arc Flash Testing And Model Development, Po-Chen Chen

Electrical Engineering Dissertations - Archive

Arc flash events could result in injuries, fatalities, and lead to severe medical expenses, equipment replacement cost, and even litigation, fines, and loss of business. Such events could also tremendously traumatize the personnel psychosocially and neurologically. Therefore, it is critical to accurately understand the potential arc flash hazards from all the real applications. Yet, due to the random complex nature of arc flash events and great number of uncertain variables involved, there are challenges to provide mathematical models for equipment designers in determining the arc-flash fault current and the incident energy of various types of events. The early arc flash …

Autonomous Teaming Of Multileader System - Robust Cluster Formation Approach, Maryam N. Naleini

Electrical Engineering Dissertations - Archive

The cluster consensus problem of Multileader MAS Is considered and the clustering problem of interconnected multileader systems is formulated as a disturbance attenuation problem. For the first time, it's proved that the multileader MAS can reach cluster consensus without limiting the communication between the clusters. The combination of Small Gain Theorem and H8 optimization has been designed in the graphical differential game platform to prove the stability for the system. At the end, an online off-policy reinforcement learning algorithm is developed to find the solution to the H8 optimal problem of multileader MAS with completely unknown systems.

Machine Learning For Target Detection Using Uwb Radar Sensor Networks, Dheeral Naresh Bhole

Electrical Engineering Dissertations - Archive

Machine learning (ML) has recently been used to solve critical problems. This dissertation focuses on developing systems using Ultra-Wideband (UWB) wireless sensor networks and machine learning to solve critical tasks such as target detection in various challenging scenarios. These tasks have been researched for several years and efforts have been made to achieve universal solutions. In the first part of this dissertation, we have proposed a system to detect metallic targets in foliage environment. Mission critical systems need to be ready for the harsh working environment such as dense foliage, water bodies, rain, heavy winds and other natural challenges. Extreme …

Optofluidic Droplet Lasers Enabled By Fluorescence Resonance Energy Transfer, Fariba Kenarangi

Electrical Engineering Dissertations - Archive

ABSTRACT: Over the past decade, optofluidic lasers have gained much popularity owing to their unique optical and mechanical properties. Optofluidic lasers are flexible, reconfigurable, easy to fabricate and their emission spectrum can be dynamically tuned. One type of these lasers with high Q-factors, is optofluidic droplet laser, which is a miniaturized ring resonator consists of liquid gain medium and optical microcavity made of two immiscible liquid phases. As light couples into the cavity, the whispering gallery mode will be guided around the concaved closed loop surface and it will be constantly reflected owing to total internal reflection. Due to its …

Towards On-Chip Integrated Sensors: Photonic Crystal Optical Sensors And Lasers, Zhonghe Liu

Electrical Engineering Dissertations - Archive

Supervising Professor: Weidong Zhou The field of compact integrated optical platform has developed into a new era in the past two decades. On one hand, the semiconductor optoelectronic devices are becoming smaller and cheaper thanks to the development of complementary metal-oxide semiconductor (CMOS) fabrication technologies; on the other hand, the applications of optoelectronics have been deeply coupled to other fields to realize more complicated implementations. Photonic crystal slab (PCS) structure has been playing an increasingly important role in these optical devices, active or passive, by enabling a variety of light-matter interaction mechanisms. The objective of this dissertation is to investigate …

System Identification Of Linear And Non-Linear Dynamical Systems Using Semi-Definite Programming Via Penalized Parabolic Relaxation Method, Adnan Nasir

Electrical Engineering Dissertations - Archive

This document is prepared to highlight the difference between two very important fields in the realm of Convex Optimization, Machine Learning, Artificial Intelligence and many such sprouting advance fields currently impacting the whole world. The main aim of the recent SDP algorithms is to relax the NP-Hard Convex optimization problems and transform them into amenable jobs without strong theoretical guarantees, but these algorithms tends to approximate the practical in demand applications in many of the aforementioned fields. Moreover, The lack of theoretical guarantee makes the SDP relaxation in-exact and unoptimizable in finite duration. The actual world applications most of the …

Verification And Validation Of Power Converters For Use In Future Power System Architectures, Alexander Johnston

Electrical Engineering Dissertations - Archive

Electronics are more widely penetrating almost every area of society and as they do, the demand to supply them with regulated power increases considerably. The scale of the electronic power distribution systems needed ranges from those in very small handheld consumer electronic devices all the way up to those needed in large buildings, ships, and cities. The energy supplied within these power distribution systems can come from many different generation sources that operate either individually or simultaneously. When power electronics are controlled properly, simultaneous generation sources can be employed in a way that optimizes them according to the user’s desired …

Photonic Crystal Surface Emitting Lasers, Akhil Raj Kumar Kalapala

Electrical Engineering Dissertations - Archive

ABSTRACT: Since the initial proposal in 1999 by Noda et al., photonic crystal surface emitting lasers (PCSELs) have proven to achieve large area, coherent lasing with a narrow, single mode beam. Owing to their unique orthogonal electrical/optical cavity scheme, PCSELs have emerged as one of the most promising platforms for high power diode lasers. The evanescent coupling of the optical mode in the active region with the photonic crystal layer enables large area two dimensional in-plane lasing mode in the photonic crystal cavity due to bandedge effect. Bragg’s multi-order diffraction provides the necessary feedback for the lasing and enhances surface …

Evaluation And Modeling Of Power System Components, Zachary Ryan Bailey

Electrical Engineering Dissertations - Archive

Future power system architectures will rely on a combination of rotating machines, power electronic devices, and energy storage. While it is possible to procure each component separately and conduct studies incorporating these devices into a system, increases in computing power and advanced computer modeling software have expanded the opportunity for research to be conducted on power system architectures without the need for actual hardware. This provides flexibility by allowing the user to design models of individual components that can then be integrated together or effortlessly interchanged depending on the function or testbed design that is being studied. The UTA IDEAL …

Microfluidic Flow Focusing Platforms For Optofluidic Droplet Laser Development, Chen Zhang

Electrical Engineering Dissertations - Archive

ABSTRACT: Optofluidic droplet lasers have been developed for different applications in biomedical sciences, such as biosensing, cell tracking, tissue imaging, on-chip spectroscopy, and flow cytometry. Utilizing different generation methods, droplet lasers can be categorized as either static droplet lasers or droplet lasers on the flow. Static droplet lasers, which are supported by a surface or levitated by an external force, can be optically probed for an extended period of time, and thus enabling continuous monitoring of the lasing emission. However, static droplet lasers suffer from low-throughput generation, large size distribution, and poor reproducibility. In contrast, droplet lasers on the flow …