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open access

Design of a Wearable Flexible Resonant Body Temperature Sensor with Inkjet-Printing

Description: A wearable body temperature sensor would allow for early detection of fever or infection, as well as frequent and accurate hassle-free recording. This thesis explores the design of a body-temperature-sensing device inkjet-printed on a flexible substrate. All structures were first modeled by first-principles, theoretical calculations, and then simulated in HFSS. A variety of planar square inductor geometries were studied before selecting an optimal design. The designs were fabricated using multi… more
Date: May 2020
Creator: Horn, Jacqueline Marie
open access

High-Performance Detectors Based on the Novel Electronic and Optoelectronic Properties of Crystalline 2D van der Waals Solids

Description: In this work, we study the properties and device applications of MoS2, black phosphorus, MoOx, and NbSe2. We first start with the design, fabrication, and characterization of ultra-high responsivity photodetectors based on mesoscopic multilayer MoS2. The device architecture is comprised of a metal-semiconductor-metal (MSM) photodetector, where Mo was used as the contact metal to suspended MoS2 membranes. The dominant photocurrent mechanism was determined to be the photoconductive effect, while … more
Date: May 2020
Creator: Saenz Saenz, Gustavo Alberto

Efficient Solar Energy Harvesting and Management for Wireless Sensor Networks under Varying Solar Irradiance Conditions

Description: Although wireless sensor networks have been successfully used for environmental monitoring, one of the major challenges that this technology has been facing is supplying continuous and reliable electrical power during long-term field deployment. Batteries require repetitive visits to the deployment site to replace them once discharged; admittedly, they can be recharged from solar panels, but this only works in open areas where solar radiation is unrestricted. This dissertation introduces a nove… more
Date: May 2020
Creator: Gurung, Sanjaya
open access

Gamification to Solve a Mapping Problem in Electrical Engineering

Description: Coarse-Grained Reconfigurable Architectures (CGRAs) are promising in developing high performance low-power portable applications. In this research, we crowdsource a mapping problem using gamification to harnass human intelligence. A scientific puzzle game, Untangled, was developed to solve a mapping problem by encapsulating architectural characteristics. The primary motive of this research is to draw insights from the mapping solutions of players who possess innate abilities like decision-makin… more
Date: May 2020
Creator: Balavendran Joseph, Rani Deepika
open access

Design of Ultra Wideband Low Noise Amplifier for Satellite Communications

Description: This thesis offers the design and improvement of a 2 GHz to 20 GHz low noise amplifier (LNA) utilizing pHEMT technology. The pHEMT technology allows the LNA to generate a boosted signal at a lower noise figure (NF) while consuming less power and achieving smooth overall gain. The design achieves an overall gain (S21) of ≥ 10 dB with an NF ≤ 2 dB while consuming ≤ 30 mA of power while using commercial off-the-shelf (COTS) components.
Date: May 2020
Creator: Webber, Scott

Deep Learning Approach for Sensing Cognitive Radio Channel Status

Description: Cognitive Radio (CR) technology creates the opportunity for unlicensed users to make use of the spectral band provided it does not interfere with any licensed user. It is a prominent tool with spectrum sensing functionality to identify idle channels and let the unlicensed users avail them. Thus, the CR technology provides the consumers access to a very large spectrum, quality spectral utilization, and energy efficiency due to spectral load balancing. However, the full potential of the CR techno… more
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Date: December 2019
Creator: Gottapu, Srinivasa Kiran
open access

A Feasibility Study of Cellular Communication and Control of Unmanned Aerial Vehicles

Description: Consumer drones have used both standards such as Wi-Fi as well as proprietary communication protocols, such as DJI's OcuSync. While these methods are well suited to certain flying scenarios, they are limited in range to around 4.3 miles. Government and military unmanned aerial vehicles (UAVs) controlled through satellites allow for a global reach in a low-latency environment. To address the range issue of commercial UAVs, this thesis investigates using standardized cellular technologies for com… more
Date: December 2019
Creator: Gardner, Michael Alan
open access

Optimization of RSA Cryptography for FPGA and ASIC Applications

Description: RSA cryptography is one of the most widely used cryptosystems in the world. FPGA/ASIC implementations for the classic RSA cryptosystem have high resource utilization due to the use of the Extended Euclid's algorithm for MOD inverse generation, the MOD exponent operation for encryption and decryption, and through non finite-field arithmetic. This thesis translates the RSA cryptosystem into the finite-field domain of arithmetic which greatly increases the range of encryption and decryption keys a… more
Date: December 2019
Creator: Simpson, Zachary P
open access

Modeling and Design of Antennas for Loosely Coupled Links in Wireless Power Transfer Applications

Description: Wireless power transfer (WPT) systems are important in many areas, such as medical, communication, transportation, and consumer electronics. The underlying WPT system is comprised of a transmitter (TX) and receiver (RX). For biomedical applications, such systems can be implemented on rigid or flexible substrates and can be implanted or wearable. The efficiency of a WPT system is based on power transfer efficiency (PTE). Many WPT system optimization techniques have been explored to achieve the h… more
Date: August 2019
Creator: Sinclair, Melissa Ann
open access

Realization of LSTM Based Cognitive Radio Network

Description: This thesis presents the realization of an intelligent cognitive radio network that uses long short term memory (LSTM) neural network for sensing and predicting the spectrum activity at each instant of time. The simulation is done using Python and GNU Radio. The implementation is done using GNU Radio and Universal Software Radio Peripherals (USRP). Simulation results show that the confidence factor of opportunistic users not causing interference to licensed users of the spectrum is 98.75%. The … more
Date: August 2019
Creator: Valluru, Aravind-Deshikh
open access

A Cognitive MIMO OFDM Detector Design for Computationally Efficient Space-Time Decoding

Description: In this dissertation a computationally efficient cognitive multiple-input multiple-output (MIMO) orthogonal frequency division duplexing (OFDM) detector is designed to decode perfect space-time coded signals which are able maximize the diversity and multiplexing properties of a rich fading MIMO channel. The adaptive nature of the cognitive detector allows a MIMO OFDM communication system to better meet to needs of future wireless communication networks which require both high reliability and lo… more
Date: August 2019
Creator: Grabner, Mitchell J

Quantile Regression Deep Q-Networks for Multi-Agent System Control

Description: Training autonomous agents that are capable of performing their assigned job without fail is the ultimate goal of deep reinforcement learning. This thesis introduces a dueling Quantile Regression Deep Q-network, where the network learns the state value quantile function and advantage quantile function separately. With this network architecture the agent is able to learn to control simulated robots in the Gazebo simulator. Carefully crafted reward functions and state spaces must be designed for… more
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Date: May 2019
Creator: Howe, Dustin
open access

Mesh Networking for Inter-UAV Communications

Description: Unmanned aerial systems (UASs) have a great potential to enhanced situational awareness in public safety operations. Many UASs operating in the same airspace can cause mid-air collisions. NASA and the FAA are developing a UAS traffic management (UTM) system, which could be used in public safety operations to manage the UAS airspace. UTM relies on an existing communication backhaul, however natural disasters may disrupt existing communications infrastructure or occur in areas where no backhaul e… more
Date: May 2019
Creator: Walton, Michael Tanner

Proximal Policy Optimization in StarCraft

Description: Deep reinforcement learning is an area of research that has blossomed tremendously in recent years and has shown remarkable potential in computer games. Real-time strategy game has become an important field of artificial intelligence in game for several years. This paper is about to introduce a kind of algorithm that used to train agents to fight against computer bots. Not only because games are excellent tools to test deep reinforcement learning algorithms for their valuable insight into how w… more
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Date: May 2019
Creator: Liu, Yuefan
open access

Design of Voltage Boosting Rectifiers for Wireless Power Transfer Systems

Description: This thesis presents a multi-stage rectifier for wireless power transfer in biomedical implant systems. The rectifier is built using Schottky diodes. The design has been simulated in 0.5µm and 130nm CMOS processes. The challenges for a rectifier in a wireless power transfer systems are observed to be the efficiency, output voltage yield, operating frequency range and the minimum input voltage the rectifier can convert. The rectifier outperformed the contemporary works in the mentioned criteria.
Date: May 2019
Creator: Suri, Ramaa Saket
open access

Implementations of Fuzzy Adaptive Dynamic Programming Controls on DC to DC Converters

Description: DC to DC converters stabilize the voltage obtained from voltage sources such as solar power system, wind energy sources, wave energy sources, rectified voltage from alternators, and so forth. Hence, the need for improving its control algorithm is inevitable. Many algorithms are applied to DC to DC converters. This thesis designs fuzzy adaptive dynamic programming (Fuzzy ADP) algorithm. Also, this thesis implements both adaptive dynamic programming (ADP) and Fuzzy ADP on DC to DC converters to o… more
Date: May 2019
Creator: Chotikorn, Nattapong
open access

Improving Photovoltaic Panel Efficiency by Cooling Water Circulation

Description: This thesis aims to increase photovoltaic (PV) panel power efficiency by employing a cooling system based on water circulation, which represents an improved version of water flow based active cooling systems. Theoretical calculations involved finding the heat produced by the PV panel and the circulation water flow required to remove this heat. A data logger and a cooling system for a test panel of 20W was designed and employed to study the relationship between the PV panel surface temperature a… more
Date: December 2018
Creator: Joseph, Jyothis
open access

Development and Integration of a Low-Cost Occupancy Monitoring System

Description: The world is getting busier and more crowded each year. Due to this fact resources such as public transport, available energy, and usable space are becoming congested and require vast amounts of logistical support. As of February 2018, nearly 95% of Americans own a mobile cell phone according to the Pew Research Center. These devices are consistently broadcasting their presents to other devices. By leveraging this data to provide occupational awareness of high traffic areas such as public tran… more
Date: December 2018
Creator: Mahjoub, Youssif
open access

Smart Microgrid Energy Management Using a Wireless Sensor Network

Description: Modern power generation aims to utilize renewable energy sources such as solar power and wind to supply customers with power. This approach avoids exhaustion of fossil fuels as well as provides clean energy. Microgrids have become popular over the years, as they contain multiple renewable power sources and battery storage systems to supply power to the entities within the network. These microgrids can share power with the main grid or operate islanded from the grid. During an islanded scenario,… more
Date: December 2018
Creator: Darden, Kelvin S
open access

Distributed Consensus, Optimization and Computation in Networked Systems

Description: In the first part of this thesis, we propose a distributed consensus algorithm under multi-layer multi-group structure with communication time delays. It is proven that the consensus will be achieved in both time-varying and fixed communication delays. In the second part, we study the distributed optimization problem with a finite-time mechanism. It is shown that our distributed proportional-integral algorithm can exponentially converge to the unique global minimizer when the gain parameters sa… more
Date: December 2018
Creator: Yao, Lisha
open access

The Chief Security Officer Problem

Description: The Chief Security Officer Problem (CSO) consists of a CSO, a group of agents trying to communicate with the CSO and a group of eavesdroppers trying to listen to the conversations between the CSO and its agents. Through Lemmas and Theorems, several Information Theoretic questions are answered.
Date: December 2018
Creator: Tanga, Vikas Reddy
open access

Real-Time Finger Spelling American Sign Language Recognition Using Deep Convolutional Neural Networks

Description: This thesis presents design and development of a gesture recognition system to recognize finger spelling American Sign Language hand gestures. We developed this solution using the latest deep learning technique called convolutional neural networks. This system uses blink detection to initiate the recognition process, Convex Hull-based hand segmentation with adaptive skin color filtering to segment hand region, and a convolutional neural network to perform gesture recognition. An ensemble of fou… more
Date: December 2018
Creator: Viswavarapu, Lokesh Kumar
open access

Development of a Wireless Sensor Network System for Occupancy Monitoring

Description: The ways that people use libraries have changed drastically over the past few decades. Proliferation of computers and the internet have led to the purpose of libraries expanding from being only places where information is stored, to spaces where people teach, learn, create, and collaborate. Due to this, the ways that people occupy the space in a library have also changed. To keep up with these changes and improve patron experience, institutions collect data to determine how their spaces are bei… more
Date: December 2018
Creator: Onoriose, Ovie
open access

Multi-Function and Flexible Microwave Devices

Description: In this dissertation, some multi-function and flexible RF/microwave devices have been studied to solve the issues in the modern microwave system designs. First, a power divider with two functions is proposed. The first function is a zero-phase delay power divider using zero-phase impedance transformer. The second function is a power divider with impedance transforming property. To achieve the first function, the two arms are treated as zero-phase impedance transformers. When the phase requireme… more
Date: December 2018
Creator: Zhou, Mi
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