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The Proof Of Concept Of The Hurricane Imaging Radiometer: Hurricane Wind Speed And Rain Rate Retrievals, Jonathan Coto Jan 2022

The Proof Of Concept Of The Hurricane Imaging Radiometer: Hurricane Wind Speed And Rain Rate Retrievals, Jonathan Coto

Electronic Theses and Dissertations, 2020-2023

This dissertation presents the proof of concept for the Hurricane Imaging Radiometer (HIRAD), where remote sensing retrievals of the 2-dimensional wind and rain fields for several hurricanes are validated with independent measurements. A significant contribution of this dissertation is the development of a novel statistical calibration technique, whereby the HIRAD instrument is radiometrically calibrated, using modeled brightness temperatures (Tb) generated using a priori hurricane wind and rain fields that are statistically representative of the actual hurricane conditions at the time of the HIRAD brightness temperature measurements. For this calibration technique, the probability distribution function of the measured HIRAD Tb's is …

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Air Force Pilot's Recognition About The Effectiveness Of Active Noise Cancellation On Hearing Health, Performance, And Aviation Safety, Kyungtaek Hwang Jan 2022

Air Force Pilot's Recognition About The Effectiveness Of Active Noise Cancellation On Hearing Health, Performance, And Aviation Safety, Kyungtaek Hwang

Electronic Theses and Dissertations, 2020-2023

The purpose of this thesis is to suggest the application of Active Noise Cancellation in Air Force pilot headset and helmet not only to reduce noise-induced hearing damage, but also to enhance pilot performance and aviation safety. Despite the recent advances of sound treatment technology, the interior sounds of a military aircraft exceed the damage risk criterion of 8 hrs/day exposure. Air Force pilots are flying under the extreme condition where noise is severe and prevalent. The exposure to noise can lead to permanent hearing loss, stress and fatigue, unintelligible communication, and deterioration of speech perception and recall. With all …

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Mixed-Criticality System Design For Real-Time Scheduling And Routing Upon Platforms With Uncertainties, Sudharsan Vaidhun Bhaskar Jan 2022

Mixed-Criticality System Design For Real-Time Scheduling And Routing Upon Platforms With Uncertainties, Sudharsan Vaidhun Bhaskar

Electronic Theses and Dissertations, 2020-2023

Unlike typical computing systems, applications in real-time systems require strict timing guarantees. In the pursuit of providing guarantees, the complex dynamic behaviors of these systems are simplified using models to keep the analysis tractable. In order to guarantee safety, such models often involve pessimistic assumptions. While the amount of pessimism was reasonable for simple computing platforms, for modern platforms the pessimism involves ignoring features that improve performance such as cache usage, instruction pipelines, and more. In this work, we explore routing and scheduling problems in real-time systems, where the uncertainties in the operation are carefully accounted for by complex models …

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Not All Influence Is Born Equal: On The Effects Of Various Types Of Behavioral Influence Relationships On Social Media, Chathurani Senevirathna Jan 2022

Not All Influence Is Born Equal: On The Effects Of Various Types Of Behavioral Influence Relationships On Social Media, Chathurani Senevirathna

Electronic Theses and Dissertations, 2020-2023

Typically, online social influence is analyzed using a single metric approach. However, social influence is not monolithic; different users exercise different influences in different ways, and influence is correlated with the user and content-specific attributes. One such attribute could be whether the action is an initiation of a new post, a contribution to a post, or a sharing of an existing post. Thus, this dissertation uses this platform-independent action classification and models the influence as multiple entities and examines social networks through the perspective of behavioral influence propagation. Two empirical studies are present in this dissertation. The first study presents …

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A Flexible 3d Architecture For Cooling Future Generation Devices, Khan Mohammad Rabbi Jan 2022

A Flexible 3d Architecture For Cooling Future Generation Devices, Khan Mohammad Rabbi

Electronic Theses and Dissertations, 2020-2023

Systems that consume and convert energy produce thermal energy as a byproduct. This generation of thermal energy, if not dissipated properly, contributes to the significant temperature rise of the overall system. This temperature rise can lead to reduced efficiency and system-level failure. Future technologies will continue to face such thermal challenges. In fact, next-gen devices will demand flexible thermal management architectures for high-performance operation. To tackle these challenges, innovative liquid cooling technologies and high-speed thermal diagnostic systems must be developed simultaneously. Active and passive pulsation-liquid-cooling techniques are currently an attractive thermal management solution. In an active cooling mode, the influence …

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Mos2 Based Memristive Synapses For Neuromorphic Computing, Adithi Pandrahal Krishnaprasad Sharada Jan 2022

Mos2 Based Memristive Synapses For Neuromorphic Computing, Adithi Pandrahal Krishnaprasad Sharada

Electronic Theses and Dissertations, 2020-2023

Brain inspired computing enabled by memristors have gained prominence over the years due to its nano-scale footprint, reduced complexity for implementing synapses and neurons. Several demonstrations show two-dimensional (2D) materials as a promising platform for realization of robust and energy-efficient memristive synapses. Ideally, a synapse should exhibit low cycle-to-cycle (C-C) and device-to-device (D-D) variability along with high maximum /minimum conductance (Gmax/Gmin) ratio, linearity and symmetry in weight update for obtaining high learning accuracy in neural networks (NNs). However, the demonstration of neuromorphic circuits using conventional materials systems has been limited by high C-C and D-D variability and non-linearity in the …

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Reconfigurable Load-Modulated Power Amplifier For Energy- And Spectrum-Efficient Wireless Communications, Haifeng Lyu Jan 2022

Reconfigurable Load-Modulated Power Amplifier For Energy- And Spectrum-Efficient Wireless Communications, Haifeng Lyu

Electronic Theses and Dissertations, 2020-2023

With the increasing demand for faster date rates and extensive user connectivities, the complex modulation schemes and large-scaled arrays have been widely researched and employed in the modern wireless links e.g., 5G and beyond-5G systems. These pose major challenges to design the power amplifiers (PAs) to accommodate the system level evolution. As the critical part, the power amplifiers (PAs) dominate the output power, efficiency, linearity and reliability of the radio frequency (RF) transmitter. Consequently, the PA's capability of maintaining an efficient, linear and reliable signal amplification operation is essential to the communication systems. On the other hand, due to the …

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4.74 Ghz Harmonically Operated Saw Device For Sensing Applications And Interrogation System, Michael Morales Otero Jan 2022

4.74 Ghz Harmonically Operated Saw Device For Sensing Applications And Interrogation System, Michael Morales Otero

Electronic Theses and Dissertations, 2020-2023

Surface acoustic wave (SAW) devices have provided solutions to many sensor applications. With the increasing use of the electromagnetic spectrum, the adoption of higher frequencies for new developments is becoming a necessity. SAW devices represent a solution for advancing many emerging sensor's needs given their inherent advantages such as: wireless operation, low cost, and ease of fabrication. However, the SAW technology has been typically limited to frequencies under 3 GHz due to size limitations, increased SAW losses, and the need of an interrogation system suitable for reading SAW sensors at higher frequencies. This dissertation presents the work done to push …

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Development Of A Dual-Mode Cmos Microelectrode Array For The Simultaneous Study Of Electrochemical And Electrophysiological Activities Of The Brain, Geoffrey Mulberry Jan 2022

Development Of A Dual-Mode Cmos Microelectrode Array For The Simultaneous Study Of Electrochemical And Electrophysiological Activities Of The Brain, Geoffrey Mulberry

Electronic Theses and Dissertations, 2020-2023

Medical diagnostic devices are in high demand due to increasing cases of neurodegenerative diseases in the aging population and pandemic outbreaks in our increasingly connected global community. Devices capable of detecting the presence of a disease in its early stages can have dramatic impacts on how it can be treated or eliminated. High cost and limited accessibility to diagnostic tools are the main barriers preventing potential patients from receiving a timely disease diagnosis. This dissertation presents several devices that are aimed at providing higher quality medical diagnostics at a low cost. Brain function is commonly studied with systems detecting the …

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Power Inductors: Design, Modeling And Analysis, Subash Pokharel Jan 2022

Power Inductors: Design, Modeling And Analysis, Subash Pokharel

Electronic Theses and Dissertations, 2020-2023

Power inductors, or reactors as they are called in the power industry, are one of the fundamental components of a power system. They serve various purposes in both conventional and emerging power systems including: power flow control, fault current limitation, reactive power compensation, harmonic filtering, and others. This dissertation explores the design and applications of conventional power inductors and ways to overcome their shortcomings and expand their functionalities. In addition, novel inductor designs are proposed and analyzed to address power system challenges. A series of inductors, including traditional constant reactance inductor, gapless ferromagnetic core reactor (GFCR) (both costant and variable …

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Reduced Footprint Probabilistic Inference Networks Using Novel Hybrid She-Mtj/Cmos Based Majority Gate, Harshavardhan Reddy Thummala Jan 2022

Reduced Footprint Probabilistic Inference Networks Using Novel Hybrid She-Mtj/Cmos Based Majority Gate, Harshavardhan Reddy Thummala

Electronic Theses and Dissertations, 2020-2023

In recent years, innovations in machine learning using artificial neural networks (ANN) have significantly increased and led to various applications like image recognition, text classification, machine translation, sequence recognition, etc. Earlier, research was focused on software-based DBNs, which are implemented on conventional von-Neumann architectures that provided flexibility but had few limitations. Recent studies have implemented hardware-based designs like FPGA-based, CMOS based, RRAM-based, and MRAM-based designs to overcome these limitations. Hybrid CMOS-MTJ-based RBMs provided significant area and energy improvements compared to other techniques. We herein implemented Spatial and Temporal redundant probabilistic interpolation network to improve the accuracy and provide fault tolerance …

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Grid-Interactive Buildings: Modeling, Operations, And Security, Guanyu Tian Jan 2022

Grid-Interactive Buildings: Modeling, Operations, And Security, Guanyu Tian

Electronic Theses and Dissertations, 2020-2023

Smart grids and smart buildings are two highly interdependent energy infrastructure systems. Buildings rely on the grid to provide reliable power while their flexibility can also be utilized to enhance the reliability and efficiency of power system operations. The quantification of heating, ventilation, and air condition (HVAC) system flexibility is critical to the operations of both the grid and buildings in demand response (DR) programs. However, the flexibility quantification is challenging due to the non-linearity and non-convexity of thermal dynamics associated with HVAC components. This dissertation proposes a novel HVAC flexibility quantification method based on a semidefinite programming (SDP) formulation. …

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Leveraging Human-Centered Insights And Vision Transformers To Understand And Detect Online Risks In Teens' Private Social Media Conversations On Instagram, Joshua Gracie Jan 2022

Leveraging Human-Centered Insights And Vision Transformers To Understand And Detect Online Risks In Teens' Private Social Media Conversations On Instagram, Joshua Gracie

Electronic Theses and Dissertations, 2020-2023

With the growing ubiquity of the internet and internet enabled devices, the issue of online risk and the need for safety measures against such risks has grown paramount. Many researchers have analyzed the scope and characteristics of online risk, especially with respect to demographics, yet few have studied the risky media itself. This work sets out to move the conversation from surveys and interviews to content analysis and automation through a comprehensive thematic analysis of online multi-media risks (images and videos) sent to and from teens in private messages on Instagram. These messages, along with demographic information such as age …

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Multivariate Cognitive Walkthrough Of Qubitvr: An Educational Quantum Computing, Virtual Reality Application, Pauline Johnson Jan 2022

Multivariate Cognitive Walkthrough Of Qubitvr: An Educational Quantum Computing, Virtual Reality Application, Pauline Johnson

Electronic Theses and Dissertations, 2020-2023

Quantum computing is a promising field but understanding how it works can be challenging for a beginner. There are also not many educational resources to visualize and learn about quantum computing. To advance knowledge in this area, we have created QubitVR, which employs a Bloch sphere representation of a qubit, and supports trajectory visualizations and state equations in a virtual reality (VR) setting. We also conducted a multivariate cognitive walkthrough with subject matter experts (SMEs) on QubitVR to assess the effectiveness of trajectory visualizations and state equations in learning about quantum gates. The results were that trajectory visualizations aided users …

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Quantum Graph Parameters, Parisa Darbari Kozekanan Jan 2022

Quantum Graph Parameters, Parisa Darbari Kozekanan

Electronic Theses and Dissertations, 2020-2023

This dissertation considers some of the advantages, and limits, of applying quantum computing to solve two important graph problems. The first is estimating a graph's quantum chromatic number. The quantum chromatic number is the minimum number of colors necessary in a two-player game where the players cannot communicate but share an entangled state and must convince a referee with probability one that they have a proper vertex coloring. We establish several spectral lower bounds for the quantum chromatic number. These lower bounds extend the well-known Hoffman lower bound for the classical chromatic number. The second is the Pattern Matching on …

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Methods For Defending Neural Networks Against Adversarial Attacks, Sharvil Shah Jan 2022

Methods For Defending Neural Networks Against Adversarial Attacks, Sharvil Shah

Electronic Theses and Dissertations, 2020-2023

Convolutional Neural Networks (CNNs) have been at the frontier of the revolution within the field of computer vision. Since the advent of AlexNet in 2012, neural networks with CNN architectures have surpassed human-level capabilities for many cognitive tasks. As the neural networks are integrated in many safety critical applications such as autonomous vehicles, it is critical that they are robust and resilient to errors. Unfortunately, it has recently been observed that deep neural network models are susceptible to adversarial perturbations which are imperceptible to human vision. In this thesis, we propose a solution to defend neural networks against white box …

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Algorithms For The Detection Of Resolved And Unresolved Targets In The Infrared Bands, Bruce Mcintosh Jan 2022

Algorithms For The Detection Of Resolved And Unresolved Targets In The Infrared Bands, Bruce Mcintosh

Electronic Theses and Dissertations, 2020-2023

This dissertation proposes algorithms for the detection of both resolved and unresolved targets in the infrared bands. Recent breakthroughs in deep learning have spurred major advancements in computer vision, but most of the attention and progress has been focused on RGB imagery from the visual band. The infrared bands such as Long Wave Infrared (LWIR), Medium Wave Infrared (MWIR), Short Wave Infrared (SWIR) and Near Infrared (NIR) each respond differently to physical phenomena, providing information that can be used to better understand the environment. The first task addressed is that of detecting vehicles in heavy clutter in MWIR imagery. A …

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Load Forecasting And Synthetic Data Generation For Smart Home Energy Management System, Mina Razghandi Jan 2022

Load Forecasting And Synthetic Data Generation For Smart Home Energy Management System, Mina Razghandi

Electronic Theses and Dissertations, 2020-2023

A number of recent trends, such as the increased power consumption in developed and developing countries, the dangers associated with greenhouse gases, the potential shortages of fossil fuels, and the increasing availability of solar and wind energy act as motivating factors for the development of more intelligent and efficient systems both on the power provider as well as the consumer side. One of the most important prerequisites for making efficient energy management decisions is the ability to predict energy production and consumption patterns. While long-term forecasting of average consumption had been extensively used to direct investments in the energy grid, …

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Visual Question Answering: Exploring Trade-Offs Between Task Accuracy And Explainability, Aisha Urooj Jan 2022

Visual Question Answering: Exploring Trade-Offs Between Task Accuracy And Explainability, Aisha Urooj

Electronic Theses and Dissertations, 2020-2023

Given visual input and a natural language question about it, the visual question answering (VQA) task is to answer the question correctly. To improve a system's reliability and trustworthiness, it is imperative that it links the text (question and answer) to specific visual regions. This dissertation first explores the VQA task in a multi-modal setting where questions are based on video as well as subtitles. An algorithm is introduced to process each modality and their features are fused to solve the task. Additionally, to understand the model's emphasis on visual data, this study collects a diagnostic set of questions which …

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Computational Methods To Analyze Next-Generation Sequencing Data In Genomics And Metagenomics, Saidi Wang Jan 2022

Computational Methods To Analyze Next-Generation Sequencing Data In Genomics And Metagenomics, Saidi Wang

Electronic Theses and Dissertations, 2020-2023

This thesis focuses on two important computational problems in genomics and metagenomics with the public available next-generation sequencing data. One is about gene regulation, for which we explore how distal regulatory elements may interact with the proximal regulatory elements. The other is about metagenomics, in which we study how to reconstruct bacterial strain genomes from shotgun reads. Studying gene regulation, especially distal gene regulation, is important because regulatory elements, including those in distal regulatory regions, orchestrate when, where and how much a gene is activated under every experimental condition. Their dysfunction results in various types of diseases. Moreover, the current …

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Characteristics Of Rotating Detonation Engines For Propulsion And Power Generation, Robert Burke Jan 2022

Characteristics Of Rotating Detonation Engines For Propulsion And Power Generation, Robert Burke

Electronic Theses and Dissertations, 2020-2023

Conventional engines are limited by the efficiency of their combustion mode. Compared to present constant pressure deflagration-based engines, detonation-based systems can realize a higher thermodynamic cycle efficiency, making them an attractive candidate for next generation propulsion systems that will take humanity to hypersonic speeds and even to Mars. For all its performance gains, detonation engines are still far off from implementation. One system, the rotating detonation engine (RDE) is promising as a detonation-based engine concept for its stability, simplicity, and versatility. For these reasons, RDEs have been the subject of studies internationally in efforts to understand their operation and integration …

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A Human-Centered Approach To Improving Adolescent Online Sexual Risk Detection Algorithms, Afsaneh Razi Jan 2022

A Human-Centered Approach To Improving Adolescent Online Sexual Risk Detection Algorithms, Afsaneh Razi

Electronic Theses and Dissertations, 2020-2023

Computational risk detection has the potential to protect especially vulnerable populations from online victimization. Conducting a comprehensive literature review on computational approaches for online sexual risk detection led to the identification that the majority of this work has focused on identifying sexual predators after-the-fact. Also, many studies rely on public datasets and third-party annotators to establish ground truth and train their algorithms, which do not accurately represent young social media users and their perspectives to prevent victimization. To address these gaps, this dissertation integrated human-centered approaches to both creating representative datasets and developing sexual risk detection machine learning models to …

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An Investigation Of The Relationship Between Respiration And Seismocardiographic Signals Using Signal Processing, Machine Learning And Finite Element Analysis, Tanvir Hassan Jan 2022

An Investigation Of The Relationship Between Respiration And Seismocardiographic Signals Using Signal Processing, Machine Learning And Finite Element Analysis, Tanvir Hassan

Electronic Theses and Dissertations, 2020-2023

Cardiovascular disease (CVD) is one of the major causes of death worldwide. Disease management, as well as patient health, can be significantly improved by early detection of patient deterioration and proper intervention. Review of the patient's medical history and physical examination including stethoscope auscultation and electrocardiograms (ECG), echocardiography imaging, numerous blood testing, and computed tomography are common means of evaluating cardiac function. Seismocardiographic (SCG) signals are the vibrations of the chest wall due to the mechanical activity of the heart. These signals can provide useful information about heart function and could be used to diagnose cardiac problems. The variability in …

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The Effects Of Supersonic Reacting Flow Over A Wedge, Taylor R. Brown Jan 2022

The Effects Of Supersonic Reacting Flow Over A Wedge, Taylor R. Brown

Honors Undergraduate Theses

There is a growing need for a fundamental understanding of how detonations are formed and sustained as propulsion technology advances toward the use of detonation-based engines. The deflagration-to-detonation transition (DDT) phenomenon is studied to better understand both the fundamentals of detonation physics and the conditions surrounding how detonations are formed and sustained. This research aims to study the effects of a wedge on DDT and detonation formation. A hydrogen-air mixture is pumped into a chamber and ignited by a spark plug. Turbulence-driven flame acceleration is induced by turbulators in the chamber through which the flame propagates. The flame then flows …

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Exploration Of Warm-Up Protocols On Muscular Fatigue, Sahil Kapadia Jan 2022

Exploration Of Warm-Up Protocols On Muscular Fatigue, Sahil Kapadia

Honors Undergraduate Theses

Muscular dystrophy is a genetically linked myopathy with no cure available. The lack of a cure makes early detection and treatment of muscular dystrophy imperative. When reviewing protocols examining muscular fatigue at submaximal isometric contractions, proper warm-up appeared to be absent and could have caused skewed results and conclusions. This study examines the effects of implementing a warm-up protocol before fatiguing trials. In this study, 10 adult subjects conducted fatiguing protocols with the right rectus at submaximal isometric contractions. The warm-up period included a light walk along with contractions at 20% and 33% of maximal voluntary isometric contraction (MVIC) levels. …

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Probing The Effect Of Hyperglycemia On Endothelial Force Generation And Transmission, Jovani J. Gutierrez Jan 2022

Probing The Effect Of Hyperglycemia On Endothelial Force Generation And Transmission, Jovani J. Gutierrez

Honors Undergraduate Theses

This thesis intends to utilize biomechanics to study the endothelial biomechanical response in a static hyperglycemic microenvironment. Hyperglycemia is a diabetic condition with abnormally high levels of glucose in the bloodstream. The effects of hyperglycemia over time lead to vascular complications resulting in patients being more prone to cardiovascular diseases. Current studies have focused on the molecular mechanisms affected by hyperglycemia; however, the mechanical mechanisms by which hyperglycemia causes vascular structural and functional changes are understudied. Therefore, to study the effects of hyperglycemia in the endothelium, Human Umbilical Vein Endothelial Cells (HUVEC) were cultured under three glucose conditions: normal glucose …

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Influence Of Growth Parameters On The Synthesis Of Mos2 Films, Victor Okonkwo Jan 2022

Influence Of Growth Parameters On The Synthesis Of Mos2 Films, Victor Okonkwo

Honors Undergraduate Theses

Information processing is crucial in modern society, placing a great emphasis on the performance of optoelectronic devices to match ever increasing processing and memory needs. Within these devices, MoS2 has demonstrated great potential as transistors due to its enhanced electrostatic control. As increased layer thickness of quality MoS2 films have been shown to boost the performance of its transistors, growth parameters for the synthesis of ideally uniform and large area multilayered films via chemical vapor deposition were investigated. By increasing the flow pressure in the system and the growth time, increasing levels of thickness and nucleation density was …

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Examining Cooperative System Responses Against Grid Integrity Attacks, Alexander D. Parady Jan 2022

Examining Cooperative System Responses Against Grid Integrity Attacks, Alexander D. Parady

Honors Undergraduate Theses

Smart grid technologies are integral to society’s transition to sustainable energy sources, but they do not come without a cost. As the energy sector shifts away from a century’s reliance on fossil fuels and centralized generation, technology that actively monitors and controls every aspect of the power infrastructure has been widely adopted, resulting in a plethora of new vulnerabilities that have already wreaked havoc on critical infrastructure. Integrity attacks that feedback false data through industrial control systems, which result in possible catastrophic overcorrections and ensuing failures, have plagued grid infrastructure over the past several years. This threat is now at …

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Thrust Augmentation Of Rotating Detonation Rocket Engines, Alexander G. Rodriguez Jan 2022

Thrust Augmentation Of Rotating Detonation Rocket Engines, Alexander G. Rodriguez

Honors Undergraduate Theses

This thesis aims to perform a detailed analysis on a 5th Order Polynomial Nozzle, verifying its effectiveness in improving the thrust performance of a Rotating Detonation Rocket Engine. Rotating detonation engines are a promising engine type that uses detonations as a means of combustion rather than traditional conflagration. Through this method, these engines can produce significant amounts of energy while burning less fuel in the process. However, exhaust flow instabilities and swirl limit the engine's potential for use as a means of propulsion. The 5th Order Polynomial Nozzle was previously demonstrated to reduce and control this swirl; however, analysis was …

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Learning And Decision Making In Social Media Networks, Zhecheng Qiang Jan 2022

Learning And Decision Making In Social Media Networks, Zhecheng Qiang

Electronic Theses and Dissertations, 2020-2023

Social media is a virtual community where users share news, ideas, interests, and information. Learning the information diffusion dynamics and making decisions correspondingly, e.g., selecting the seed nodes to maximize the influence, have been widely applied to the areas of viral marketing and cyber security. In this dissertation, we study the problem of learning diffusion process, i.e., infection prediction, in social media networks utilizing both feature-based machine learning methods and mathematical model-based methods. For feature-based machine learning methods, the neighborhood information is treated as an important feature together with user profile and content similarity features. For model-based methods, two distinctive …

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