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Asynchronous Level Crossing ADC for Biomedical Recording Applications

Description: This thesis focuses on the recording challenges faced in biomedical systems. More specifically, the challenges in neural signal recording are explored. Instead of the typical synchronous ADC system, a level crossing ADC is detailed as it has gained recent interest for low-power biomedical systems. These systems take advantage of the time-sparse nature of the signals found in this application. A 10-bit design is presented to help capture the lower amplitude action potentials (APs) in neural sign… more
Date: August 2021
Creator: Pae, Kieren
Item Type: Refine your search to only Thesis or Dissertation

Design of Low-Power Front End Compressive Sensing Circuitry and Energy Harvesting Transducer Modeling for Self-Powered Motion Sensor

Description: Compressed sensing (CS) is an innovative approach of signal processing that facilitates sub-Nyquist processing of bio-signals, such as a neural signal, electrocardiogram (ECG), and electroencephalogram (EEG). This strategy can be used to lower the data rate to realize ultra-low-power performance, As the count of recording channels increases, data volume is increased resulting in impermissible transmitting power. This thesis work presents the implementation of a CMOS-based front-end design with … more
Date: August 2021
Creator: Kakaraparty, Karthikeya Anil Kumar
Item Type: Refine your search to only Thesis or Dissertation
open access

Development and Application of Novel Computer Vision and Machine Learning Techniques

Description: The following thesis proposes solutions to problems in two main areas of focus, computer vision and machine learning. Chapter 2 utilizes traditional computer vision methods implemented in a novel manner to successfully identify overlays contained in broadcast footage. The remaining chapters explore machine learning algorithms and apply them in various manners to big data, multi-channel image data, and ECG data. L1 and L2 principal component analysis (PCA) algorithms are implemented and tested a… more
Date: August 2021
Creator: Depoian, Arthur Charles, II
Item Type: Refine your search to only Thesis or Dissertation

Electrical Equivalent Modeling of the Reverse Electrowetting-on-Dielectric (REWOD) Based Transducer along with Highly Efficient Energy Harvesting Circuit Design towards Self-Powered Motion Sensor

Description: Among various energy harvesting technologies reverse electrowetting-on-dielectric energy harvesting (REWOD) has been proved to harvest energy from low frequency motion such as many human motion activities (e.g. walking, running, jogging etc.). Voltage rectification and DC-DC boosting of low magnitude AC voltage from REWOD can be used to reliably self-power the wearable sensors. In this work, a commercial component-based rectifier and DC-DC converter is designed and experimentally verified, for … more
Date: August 2021
Creator: Gunti, Avinash
Item Type: Refine your search to only Thesis or Dissertation
open access

Estimation of Drone Location Using Received Signal Strength Indicator

Description: The main objective of this thesis is to propose a UAV (also called as drones) location estimation system based on LoRaWAN using received signal strength indicator in a GPS denied environment. The drones are finding new applications in areas such as surveillance, search, rescue missions, package delivery, and precision agriculture. Nearly all applications require the localization of UAV during flight. Localization is the method of determining a UAVs physical position using a real or virtual coor… more
Date: August 2021
Creator: Jagini, Varun Kumar
Item Type: Refine your search to only Thesis or Dissertation
open access

Formation Control and Path Planning Strategies for Unmanned Aerial Vehicle Swarms

Description: This dissertation focuses on the path planning of unmanned aerial vehicle (UAV) swarms under distributed and hybrid control scenarios. It presents two such models and analyzes them both from theory and practice. In the first method, a distributed formation control strategy for UAV swarm based on consensus law is presented. This model makes use of the fundamental concepts of leader-follower structure, social potential functions, and algebraic graph theory to jointly address flocking and de-confl… more
Date: August 2021
Creator: Mukherjee, Srijita
Item Type: Refine your search to only Thesis or Dissertation
open access

Traditional and Deep Learning Approaches to Color Image Compression and Pattern Recognition Problems

Description: This thesis includes three separate research projects focusing on computer vision principles and deep learning pattern recognition problems. Chapter 3 entails color quantization applications using traditional Kmeans clustering techniques and random selection of color techniques within the red, green, blue (RGB) color space to maintain a high-quality image while significantly reducing image file size. Chapter 4 consists of a handwriting character recognition algorithm using backpropagation to cl… more
Date: August 2021
Creator: Jaques, Lorenzo E
Item Type: Refine your search to only Thesis or Dissertation
open access

Object Detection for Aerial View Images: Dataset and Learning Rate

Description: In recent years, deep learning based computer vision technology has developed rapidly. This is not only due to the improvement of computing power, but also due to the emergence of high-quality datasets. The combination of object detectors and drones has great potential in the field of rescue and disaster relief. We created an image dataset specifically for vision applications on drone platforms. The dataset contains 5000 images, and each image is carefully labeled according to the PASCAL VOC st… more
Date: May 2021
Creator: Qi, Yunlong
Item Type: Refine your search to only Thesis or Dissertation
open access

Efficient Linear Secure Computation and Symmetric Private Information Retrieval Protocols

Description: Security and privacy are of paramount importance in the modern information age. Secure multi-party computation and private information retrieval are canonical and representative problems in cryptography that capture the key challenges in understanding the fundamentals of security and privacy. In this dissertation, we use information theoretic tools to tackle these two classical cryptographic primitives. In the first part, we consider the secure multi-party computation problem, where multiple us… more
Date: December 2020
Creator: Zhou, Yanliang
Item Type: Refine your search to only Thesis or Dissertation

Light Matter Interactions in Two-Dimensional Semiconducting Tungsten Diselenide for Next Generation Quantum-Based Optoelectronic Devices

Description: In this work, we explored one material from the broad family of 2D semiconductors, namely WSe2 to serve as an enabler for advanced, low-power, high-performance nanoelectronics and optoelectronic devices. A 2D WSe2 based field-effect-transistor (FET) was designed and fabricated using electron-beam lithography, that revealed an ultra-high mobility of ~ 625 cm2/V-s, with tunable charge transport behavior in the WSe2 channel, making it a promising candidate for high speed Si-based complimentary-met… more
Date: December 2020
Creator: Bandyopadhyay, Avra Sankar
Item Type: Refine your search to only Thesis or Dissertation
open access

Adaptive Slot Location in the Design of Slotted Microstrip Multi-Frequency Antenna for Radionavigation and Radiolocation Applications

Description: In light of incidents and concerns regarding the vulnerability of the global positioning system (GPS), the main purpose of the thesis is to look at alternative systems for radio guidance and to put up a serious study on such alternatives with receive and transmit antenna. There is also the need to design such antennas with multiple frequencies to offer robustness in the unlikely event that such adversarial attacks on the GPS happen. The basis on which such alternative antennas are designed is a… more
Date: August 2020
Creator: Agbor, Ikechukwu Wilson
Item Type: Refine your search to only Thesis or Dissertation

Assistive Navigation Technology for Visually Impaired Individuals

Description: Sight is essential in our daily tasks. Compensatory senses have been used for centuries by visually impaired individuals to navigate independently. The help of technology can minimize some challenges for visually impaired individuals. Assistive navigation technologies facilitate the pathfinding and tracing in indoor scenarios. Different modules are added to assistive navigation technologies to warn about the obstacles not only on the ground but about hanging objects. In this work, we attempt to… more
Date: August 2020
Creator: Norouzi Kandalan, Roya
Item Type: Refine your search to only Thesis or Dissertation
open access

The Role of Eigenvalues of Parity Check Matrix in Low-Density Parity Check Codes

Description: The new developments in coding theory research have revolutionized the application of coding to practical systems. Low-Density Parity Check (LDPC) codes form a class of Shannon limit approaching codes opted for digital communication systems that require high reliability. This thesis investigates the underlying relationship between the spectral properties of the parity check matrix and LDPC decoding convergence. The bit error rate of an LDPC code is plotted for the parity check matrix that has d… more
Date: August 2020
Creator: Adhikari, Dikshya
Item Type: Refine your search to only Thesis or Dissertation
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
Item Type: Refine your search to only Thesis or Dissertation
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
Item Type: Refine your search to only Thesis or Dissertation

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
Item Type: Refine your search to only Thesis or Dissertation
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
Item Type: Refine your search to only Thesis or Dissertation
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
Item Type: Refine your search to only Thesis or Dissertation
open access

Inkjet Printed Transition Metal Dichalcogenides and Organohalide Perovskites for Photodetectors and Solar Cells

Description: This dissertation is devoted to the development of novel devices for optoelectronic and photovoltaic applications using the promise of inkjet printing with two-dimensional (2D) materials. A systematic approach toward the characterization of the liquid exfoliated 2D inks comprising of graphene, molybdenum disulfide (MoS2), tungsten diselenide (WSe2), and 2D perovskites is discussed at depth. In the first study, the biocompatibility of 2D materials -- graphene and MoS2 -- that were drop cast onto… more
Date: May 2020
Creator: Hossain, Ridwan Fayaz
Item Type: Refine your search to only Thesis or Dissertation
open access

Interference Alignment through Propagation Delay

Description: With the rapid development of wireless communication technology, the demands for higher communication rates are increasing. Higher communication rate corresponds to higher DoF. Interference alignment, which is an emerging interference management technique, is able to substantially increase the DoF of wireless communication systems. This thesis mainly studies the delay-based interference alignment technique. The key problem lies in the design of the transmission scheme and the appropriate alloca… more
Date: May 2020
Creator: Liu, Zhonghao
Item Type: Refine your search to only Thesis or Dissertation

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
Item Type: Refine your search to only Thesis or Dissertation
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
Item Type: Refine your search to only Thesis or Dissertation
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