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Re-Design Of Precision Signal Conditioning Circuit For Detecting Schumann Resonance, Rohith Bikkina 2021 West Virginia University

Re-Design Of Precision Signal Conditioning Circuit For Detecting Schumann Resonance, Rohith Bikkina

Graduate Theses, Dissertations, and Problem Reports (ETD)

Extremely low frequencies signals are waves between 3 to 30Hz and corresponding wavelengths between 10,000 to 100,000 kilometers. The specific signals used here are generated from lightning and are excited at frequencies around 8Hz, 14Hz, 20Hz. These are often called Schumann Resonance frequencies. Several stations have been built around the world for identifying ELF waves. All of those required a sparsely populated area that was far away from electric power lines because of interference from electric noise at 50 Hz and 60Hz. This project develops and tests an amplifier and filter circuit that should assist in identifying the Schumann Resonance …


Deep Models For Improving The Performance And Reliability Of Person Recognition, Sobhan Soleymani 2021 West Virginia University

Deep Models For Improving The Performance And Reliability Of Person Recognition, Sobhan Soleymani

Graduate Theses, Dissertations, and Problem Reports (ETD)

Deep models have provided high accuracy for different applications such as person recognition, image segmentation, image captioning, scene description, and action recognition. In this dissertation, we study the deep learning models and their application in improving the performance and reliability of person recognition. This dissertation focuses on five aspects of person recognition: (1) multimodal person recognition, (2) quality-aware multi-sample person recognition, (3) text-independent speaker verification, (4) adversarial iris examples, and (5) morphed face images. First, we discuss the application of multimodal networks consisting of face, iris, fingerprint, and speech modalities in person recognition. We propose multi-stream convolutional neural network architectures …


Real Vs Fake Faces: Deepfakes And Face Morphing, Jacob L. Dameron 2021 WVU

Real Vs Fake Faces: Deepfakes And Face Morphing, Jacob L. Dameron

Graduate Theses, Dissertations, and Problem Reports (ETD)

The ability to determine the legitimacy of a person’s face in images and video can be important for many applications ranging from social media to border security. From a biometrics perspective, altering one’s appearance to look like a target identity is a direct method of attack against the security of facial recognition systems. Defending against such attacks requires the ability to recognize them as a separate identity from their target. Alternatively, a forensics perspective may view this as a forgery of digital media. Detecting such forgeries requires the ability to detect artifacts not commonly seen in genuine media. This work …


In-Situ Process Monitoring For Metal Additive Manufacturing (Am) Through Acoustic Technique, Md Shahjahan Hossain 2021 Georgia Southern University

In-Situ Process Monitoring For Metal Additive Manufacturing (Am) Through Acoustic Technique, Md Shahjahan Hossain

College of Graduate Studies: Theses & Dissertations

Additive Manufacturing (AM) is currently a widely used technology in different industries such as aerospace, medical, and consumer products. Previously it was mainly used for prototyping of the products, but now it is equally valuable for commercial product manufacturing. More profound understanding is still needed to track and identify defects during the AM process to ensure higher quality products with less material waste. Nondestructive testing becomes an essential form of testing for AM parts, where AE is one of the most used methods for in situ process monitoring. The Acoustic Emission (AE) approach has gained a reputation in nondestructive testing …


Deep Learning Assisted Intelligent Visual And Vehicle Tracking Systems, Liang Xu 2021 Virginia Commonwealth University

Deep Learning Assisted Intelligent Visual And Vehicle Tracking Systems, Liang Xu

Theses and Dissertations

Sensor fusion and tracking is the ability to bring together measurements from multiple sensors of the current and past time to estimate the current state of a system. The resulting state estimate is more accurate compared with the direct sensor measurement because it balances between the state prediction based on the assumed motion model and the noisy sensor measurement. Systems can then use the information provided by the sensor fusion and tracking process to support more-intelligent actions and achieve autonomy in a system like an autonomous vehicle. In the past, widely used sensor data are structured, which can be directly …


The Discrete Fourier Transform - A Practical Approach, David Dorran 2021 Technological University Dublin

The Discrete Fourier Transform - A Practical Approach, David Dorran

Articles

These notes on the Discrete Fourier Transform include numerous practical examples that make use of audio signals.


Energy Considerations In Blockchain-Enabled Applications, Cesar Enrique Castellon Escobar 2021 University of North Florida

Energy Considerations In Blockchain-Enabled Applications, Cesar Enrique Castellon Escobar

UNF Graduate Theses and Dissertations

Blockchain-powered smart systems deployed in different industrial applications promise operational efficiencies and improved yields, while mitigating significant cybersecurity risks pertaining to the main application. Associated tradeoffs between availability and security arise at implementation, however, triggered by the additional resources (e.g., memory, computation) required by each blockchain-enabled host. This thesis applies an energy-reducing algorithmic engineering technique for Merkle Tree root and Proof of Work calculations, two principal elements of blockchain computations, as a means to preserve the promised security benefits but with less compromise to system availability. Using pyRAPL, a python library to measure computational energy, we experiment with both the …


Product Failure Recognition Via Comparison Of Sequential And Quickest Detection Algorithms, Christopher M. Beachler 2021 University of North Florida

Product Failure Recognition Via Comparison Of Sequential And Quickest Detection Algorithms, Christopher M. Beachler

UNF Graduate Theses and Dissertations

Under similar conditions, products that are designed and used for similar tasks fail similarly. Developers may become aware of various product failure modes during the initial stages of new product generation, where redesign and failure mitigation processes can occur with minimal detriment to consumer safety. Developers strive to mitigate the potential for catastrophic failures. This thesis concentrates on when these failures occur outside of controlled conditions, specifically where the development of processes feature low accuracy sensing techniques that impact the safety and operation of the end user. This thesis develops a set of statistical analysis simulation techniques using two existing …


Analysis Of Millimeter-Wave Networks: Blockage, Antenna Directivity, Macrodiversity, And Interference, Enass Hriba 2021 West Virginia University

Analysis Of Millimeter-Wave Networks: Blockage, Antenna Directivity, Macrodiversity, And Interference, Enass Hriba

Graduate Theses, Dissertations, and Problem Reports (ETD)

Due to its potential to support high data rates at low latency with reasonable interference isolation because of signal blockage at these frequencies, millimeter-wave (mmWave) communications has emerged as a promising solution for next-generation wireless networks. MmWave systems are characterized by the use of highly directional antennas and susceptibility to signal blockage by buildings and other obstructions, which significantly alter the propagation environment. The received power of each transmission depends on the direction the corresponding antennas point and whether the signal’s path is line-of-sight (LOS), non-LOS (i.e., partially blocked), or completely blocked. A key challenge in modeling blocking in mmWave …


Sensing Methods For Two-Target And Four-Target Detection In Time-Constrained Vector Poisson And Gaussian Channels, Muhammad Fahad 2021 Michigan Technological University

Sensing Methods For Two-Target And Four-Target Detection In Time-Constrained Vector Poisson And Gaussian Channels, Muhammad Fahad

Dissertations, Master's Theses and Master's Reports

In this dissertation we consider a sensor scheduling or resource management problem for a vector Poisson and Gaussian channels. The input is a binary random vector and the output is a set of conditionally independent Poisson or Gaussian random variables. The objective is to design a scaling matrix, which is a linear transformation whose purpose is to entangle the different inputs, under a total given energy/time constraint. The two metrics are adopted to quantify the performance of the designed scaling matrix: mutual information and Bayesian inference. In other words, it is an experimental design problem where the objective is to …


Light Field Compression And Manipulation Via Residual Convolutional Neural Network, Eisa Hedayati 2021 Michigan Technological University

Light Field Compression And Manipulation Via Residual Convolutional Neural Network, Eisa Hedayati

Dissertations, Master's Theses and Master's Reports

Light field (LF) imaging has gained significant attention due to its recent success in microscopy, 3-dimensional (3D) displaying and rendering, augmented and virtual reality usage. Postprocessing of LF enables us to extract more information from a scene compared to traditional cameras. However, the use of LF is still a research novelty because of the current limitations in capturing high-resolution LF in all of its four dimensions. While researchers are actively improving methods of capturing high-resolution LF's, using simulation, it is possible to explore a high-quality captured LF's properties. The immediate concerns following the LF capture are its storage and processing …


Technique Design Of Filter On Surface-Acoustic Waves, Dilmurod Abdujalilovich Davronbekov, Zafar Tulyaganovich Khakimov 2020 Tashkent University of Information Technologies named after Muhammad al-Khwarizmi

Technique Design Of Filter On Surface-Acoustic Waves, Dilmurod Abdujalilovich Davronbekov, Zafar Tulyaganovich Khakimov

Acta of Turin Polytechnic University in Tashkent

The article describes the design of filters on surface acoustic waves (SAWs), which are selective elements and are widely used in blocks, devices and signal processing systems in telecommunications, including wireless communication systems such as cellular, trunking and others. Designs of filters for surfactants are considered, which are divided into two large groups - by functional purpose and by a systematic approach to the synthesis of performance characteristics of filters for surfactants. Optimization algorithms and methods for synthesizing surfactant filters have been developed and improved. An improved technique for the synthesis of a filter based on surface acoustic waves is …


Multibeam Array Antenna For Base Station In The Fifth-Generation Mobile Communication System, Intan Izafina Idrus 2020 Universiti Malaya

Multibeam Array Antenna For Base Station In The Fifth-Generation Mobile Communication System, Intan Izafina Idrus

Student Works (2020-2029)

Research on the fifth-generation (5G) mobile communication system has been accelerated to meet the standardization of the International Telecommunications Union for higher data traffic and higher data rates. The main requirements of the 5G mobile communication systems are the utilization of millimeter waves, the deployment of small cells, and the use of multibeam array antennas for multiple-input multiple-output schemes. Multibeam array antennas play an important role in developing a new base station to enhance system capacity, improve network coverage, and reduce co-channel interference. The main objective of this thesis is to design a single-layer multibeam array antenna at 28 GHz …


Improve The Prototype Of Low-Cost Near-Infrared Diffuse Optical Imaging System, Chen Xu, Mohammed Z. Shakil 2020 CUNY New York City College of Technology

Improve The Prototype Of Low-Cost Near-Infrared Diffuse Optical Imaging System, Chen Xu, Mohammed Z. Shakil

Publications and Research

Diffuse Optical Tomography (DOT) and Optical Spectroscopy using near-infrared (NIR) diffused light has demonstrated great potential for the initial diagnosis of tumors and in the assessment of tumor vasculature response to neoadjuvant chemotherapy. The aims of this project are 1) to test the different types of LEDs in the near-infrared range, and design the driving circuit, and test the modulation of LEDs at different frequencies; 2) to test the APDs as a detector, and build the receiver system and compare efficiency with pre-built systems. In this project, we are focusing on creating a low-cost infrared transmission system for tumor and …


A Study In Gps-Denied Navigation Using Synthetic Aperture Radar, Colton P. Lindstrom 2020 Utah State University

A Study In Gps-Denied Navigation Using Synthetic Aperture Radar, Colton P. Lindstrom

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

In modern navigation systems, GPS is vital to accurately piloting a vehicle. This is especially true in autonomous vehicles, such as UAVs, which have no pilot. Unfortunately, GPS signals can be easily jammed or spoofed. For example, canyons and urban cities create an environment where the sky is obstructed and make GPS signals unreliable. Additionally, hostile individuals can transmit personal signals intended to block or spoof GPS signals. In these situations, it is important to find a means of navigation that doesn’t rely on GPS.

Navigating without GPS means that other types of sensors or instruments must be used to …


An Exploratory Study Of Pulse Width And Delta Sigma Modulators, Logan B. Penrod 2020 Cal Poly SLO

An Exploratory Study Of Pulse Width And Delta Sigma Modulators, Logan B. Penrod

Master's Theses

This paper explores the noise shaping and noise producing qualities of Delta-Sigma Modulators (DSM) and Pulse-Width Modulators (PWM). DSM has long been dominant in the Delta Sigma Analog-to-Digital Converter (DSADC) as a noise-shaped quantizer and time discretizer, while PWM, with a similar self oscillating structure, has seen use in Class D Power Amplifiers, performing a similar function. It has been shown that the PWM in Class D Amplifiers outperforms the DSM [1], but could this advantage be used in DSADC use-cases? LTSpice simulation and printed circuit board implementation and test are used to present data on four variations of these …


Designing And Evaluating Of Mimo Systems For Millimeter-Wave Communications, Mojtaba Ahmadi Almasi 2020 Boise State University

Designing And Evaluating Of Mimo Systems For Millimeter-Wave Communications, Mojtaba Ahmadi Almasi

Boise State University Theses and Dissertations

The fifth generation (5G) of wireless communications will integrate all existing technologies while bringing its own to the system. Amongst these technologies, millimeter-wave (mmWave) is emerging as a promising solution for 5G systems. However, to fully harness the potential of mmWave communications, obstacles such as severe path loss, channel sparsity, and hardware complexity should be overcome. The existing cost-effective systems can considerably reduce the hardware complexity and partially severe path loss, while channel sparsity still remains a main problem. Other factors such as transmission reliability and coverage area should be considered in 5G mmWave communications. Non-orthogonal multiple access (NOMA) is …


Atmospheric Turbulence Distortion In Video: Restoration Utilizing Sparse Analysis, Benjamin J. Sanda 2020 Western Michigan University

Atmospheric Turbulence Distortion In Video: Restoration Utilizing Sparse Analysis, Benjamin J. Sanda

Dissertations

The removal of atmospheric turbulence (AT) distortion in long range imaging is one of the most challenging areas of research in imaging processing with an immediate need for solutions in several applications such as in military and transportation systems. AT exacerbates distortion due to non-linear geometric blur and scintillations in long-distance images and videos, severely reducing image quality and information interpretation. AT negatively impacts both human and computer vision systems, compromising visibility essential for accurate object identification and tracking.

In this dissertation, a novel sparse analysis framework is developed to address efficient AT blur and scintillation removal in video. Operating …


Power-Weighted Lpc Formant Estimation, Ruairí de Fréin 2020 Dublin Institute of Technology

Power-Weighted Lpc Formant Estimation, Ruairí De Fréin

Conference papers

A power-weighted formant frequency estimation procedure based on Linear Predictive Coding (LPC) is presented. It works by pre-emphasizing the dominant spectral components of an input signal, which allows a subsequent estimation step to extract formant frequencies with greater accuracy. The accuracy of traditional LPC formant estimation is improved by this new power-weighted formant estimator for different classes of synthetic signals and for speech. Power-weighted LPC significantly and reliably outperforms LPC and variants of LPC at the task of formant estimation using the VTR formants dataset, a database consisting of the Vocal Tract Resonance (VTR) frequency trajectories obtained by human experts …


Health Monitoring Using Deep Learning Of Acoustic And Speech Signals, Eric E. Hamke 2020 University of New Mexico

Health Monitoring Using Deep Learning Of Acoustic And Speech Signals, Eric E. Hamke

Electrical and Computer Engineering ETDs

The focus of the research is to identify stress markers in a firefighter's speech. These markers include changes in breathing patterns and changes in the fundamental frequency of an individual’s voice. The breathing patterns are characterized using the number of breaths taken in a minute and the time spent inhaling. These measures are estimated using a Restricted Boltzmann Machine to process a firefighters’ SCBA regulator sounds, as open and closed. The classifications are then combined into continuous intervals. Observing the length of the intervals and the number of interval-starts represents time spent inhaling and the breathing rates (breaths per minute). …


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