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Shift Register Puf Implementation On An Fpga, Sriram Thotakura May 2021

Shift Register Puf Implementation On An Fpga, Sriram Thotakura

Electrical and Computer Engineering ETDs

In this thesis, a novel shift register-based physical unclonable function (PUF), called SRP, is proposed. The PUF is implemented on an FPGA and leverages the internal delay variations introduced by within-die process variations that occur within the Look-up tables (LUTs), routing and switches of the FPGA. PUFs are designed to generate bitstrings and keys on-the-fly that are device-specific (unique), random and reproducible. PUFs eliminate the need for a specialized (secure) non-volatile memory(NVM) to store the secret keys. This reduces the total cost of chips and systems, particularly those used in the Internet of Things, where it is common for systems …


Self-Breakdown Study Of Spherical Electrodes In Air Spanning Pressures From Atmosphere To 2000 Psia, And Stress Times From Seconds To Nanoseconds, Joseph G. Felix May 2021

Self-Breakdown Study Of Spherical Electrodes In Air Spanning Pressures From Atmosphere To 2000 Psia, And Stress Times From Seconds To Nanoseconds, Joseph G. Felix

Electrical and Computer Engineering ETDs

In this research, a self-breakdown switch with 12.7 mm diameter spherical electrodes and a 380-micron gap was assembled and the effect of pressure and stress time on breakdown voltage and closure time were measured. Specifically, the pressure was varied from atmosphere to 2000 psia and the stress time was varied from seconds to nanoseconds. Few studies have investigated equivalent ranges of pressure and charge times on sub millimeter gap switches with electric field intensities reaching 2 MV/cm. The correlation of the parameters and switch behavior are explored in this study. In addition, the effects of humidity and electrode surface deformities …


Etched-And-Regrown Diodes On M-Plane Gan For Next Generation Power Electronic Devices, Andrew A. Aragon May 2021

Etched-And-Regrown Diodes On M-Plane Gan For Next Generation Power Electronic Devices, Andrew A. Aragon

Electrical and Computer Engineering ETDs

Demand for next-generation power electronic devices is driven by continually evolving requirements of power systems. Devices utilizing III-nitride materials (GaN) and vertical selective-area doped architectures are advantageous due to their wide- bandgap, thermal management, small form-factor, and current handling.

Such devices incorporate junctions at multiple crystalline planes. Thus, effects of impurity contamination and etch damage are investigated on the m-plane (10-10) of GaN. Impurites (Si, O, and C) are shown to reduce blocking voltage (~ 102 ×) and increase forward leakage current (~ 104 ×) in regrown versus continuously-grown p-n diodes. Elevated deep level defects at Ec – …


A Numerical Circuit Simulation Study Of High Voltage, Multi-Pulse Transmission Lines And Spark Gap Switches, Joe Ming Ju Chen Apr 2021

A Numerical Circuit Simulation Study Of High Voltage, Multi-Pulse Transmission Lines And Spark Gap Switches, Joe Ming Ju Chen

Electrical and Computer Engineering ETDs

The design and development of high voltage, multi-pulse transmission line generators is of high interest for linear accelerator and other pulse power applications. Los Alamos National Laboratory and L3 Applied Technologies are in development and testing of a multi-pulse series pulse forming water transmission line system dubbed the Series Pulse-Line Integrated Test Stand (SPLITS). The system consists of up to four water lines in series charged by a Marx bank of total capacitance and voltage of 39nF and -600kV, respectively, to produce multiple 120ns, -300kV pulses on a matched resistive load of 5.5 . There is a need for a …


A Reconfigurable Stretchable Liquid Metal Antenna, Phase Shifter, And Array For Wideband Applications, David M. Hensley Apr 2021

A Reconfigurable Stretchable Liquid Metal Antenna, Phase Shifter, And Array For Wideband Applications, David M. Hensley

Electrical and Computer Engineering ETDs

While liquid metals, such as mercury, have been used in electronics for quite some time, the non-toxic gallium based liquid metals have caused an increase in research for liquid metal applications. Some of the potential applications that have been previously presented range from reconfigurable antennas, strain and pressure sensors, and speakers and microphones to name a few. The focus of this work is to provide further research into the use of gallium based liquid metals as a reconfigurable antenna, a phase shifter, and an array. This is done by designing, constructing, and characterizing each of these reconfigurable liquid metal (LM) …


Side Channel Attack Counter Measure Using A Moving Target Architecture, Jithin Joseph Apr 2021

Side Channel Attack Counter Measure Using A Moving Target Architecture, Jithin Joseph

Electrical and Computer Engineering ETDs

A novel countermeasure to side-channel power analysis attacks called Side-channel Power analysis Resistance for Encryption Algorithms using DPR or SPREAD is investigated in this thesis. The countermeasure leverages a strategy that is best characterized as a moving target architecture. Modern field programmable gate arrays (FPGA) architectures provide support for dynamic partial reconfiguration (DPR), a feature that allows real-time reconfiguration of the programmable logic (PL). The moving target architecture proposed in this work leverages DPR to implement a power analysis countermeasure to side-channel attacks, the most common of which are referred to as differential power analysis (DPA) and correlation power analysis …


Experimental Validation Of A 3d-Printed Millimeter Wave/Thz Power Combiner, Jacob C. Giese Apr 2021

Experimental Validation Of A 3d-Printed Millimeter Wave/Thz Power Combiner, Jacob C. Giese

Electrical and Computer Engineering ETDs

The terahertz band (THz) in the electromagnetic spectrum is an untapped resource that possesses unique features for nondestructive methods of material imaging and detection. However, little advancements have been made in regard to a practical long range portable THz device. The solution proposed is an oversized cylindrical waveguide termed Power Combiner, designed to combine 12 azimuthally aligned rectangular waveguides to produce power levels suitable for threat detection at secure distances. This paper explores the physical parameters of the power combiner and the power distribution network and creates the 12 signals that allow for modification at the input of the power …


Heterogeneously Integrated Photonic Modulators And High-Volume Manufacturing Of Related Technologies, Nicholas Adam Boynton Apr 2021

Heterogeneously Integrated Photonic Modulators And High-Volume Manufacturing Of Related Technologies, Nicholas Adam Boynton

Electrical and Computer Engineering ETDs

Silicon photonics is an attractive approach to cost-effective integrated optics due to the infrastructure established for silicon CMOS electronics. The material properties of silicon however are not ideal for optical devices. Specifically, silicon lacks the ability to easily produce light-emitting devices due to its indirect bandgap, and has a centro-symmetric crystal structure which does not facilitate the Pockels effect required for linear modulation. Conversely, lithium niobate is an excellent optical material due to its strong Pockels effect but, is a notoriously difficult material to process. One method of simultaneously overcoming the material limitations of silicon and the fabrication limitations of …


On The Dynamic Generation Of Megagauss-Level Magnetic Fields On 100-Ns Timescales To Stabilize And Magnetize Pulsed-Power-Driven Liner Implosions, Gabriel A. Shipley Apr 2021

On The Dynamic Generation Of Megagauss-Level Magnetic Fields On 100-Ns Timescales To Stabilize And Magnetize Pulsed-Power-Driven Liner Implosions, Gabriel A. Shipley

Electrical and Computer Engineering ETDs

This dissertation presents analysis of experiments and simulations executed to develop the auto-magnetizing liner concept (AutoMag) for use as an alternative premagnetization mechanism for MagLIF. Tests of each stage of AutoMag (magnetization, dielectric breakdown, and implosion) were executed on the Mykonos accelerator and the Z accelerator. Experiments demonstrate strong peak axial magnetic field production (20 – 150 T), dielectric breakdown initiation that depends on global induced electric field across the target, and a level of cylindrical implosion uniformity high enough to be useful for prospective fusion-fuel-filled (auto-magnetized MagLIF) experiments.

This dissertation also presents detailed simulations of the Solid Liner Dynamic …


Computational_Electromagnetic Modeling (Cem) Of Foliage Penetration (Fopen), Monica R. Jaramillo Apr 2021

Computational_Electromagnetic Modeling (Cem) Of Foliage Penetration (Fopen), Monica R. Jaramillo

Electrical and Computer Engineering ETDs

Foliage penetration (FOPEN) radar at lower frequencies (UHF, VHF) is a well-studied area with a wide set of contributions. However, there is growing interest in using higher Ku-band frequencies (12-18 GHz frequency range) for FOPEN. In particular, the reduced wavelength sizes (centimeters range) provide some key saliencies for developing more optimized foliage detection solutions. The disadvantage is that exploiting Ku-band for FOPEN is complicated because higher frequencies have much more pronounced scattering effects due to their smaller wavelengths. Despite these challenges, certain foliage characteristics and signal parameters can help improve electromagnetic (EM) wave penetration in the Ku-band such as foliage …


Source Localization With Machine Learning, Arjun Gupta Jan 2021

Source Localization With Machine Learning, Arjun Gupta

Electrical and Computer Engineering ETDs

Source localization with sensor arrays have found applications across domains beginning with radar and sonar, astronomy, acoustics, bio-medical devices and more recently in autonomous cars and adaptive communication systems. The knowledge of the spatial spectrum not only provide information about the source and interference but also assists in increasing signal integrity and avoid interference. This provides an added degree of freedom in the form of spatial diversity. This research investigates spatial spectrum estimation of waveforms from the signals sampled by arbitrarily distributed sensors. Conventional high resolution algorithms such as root-MuSiC fails to perform accurate source localization due to the reliance …


Theoretical And Experimental Studies Of The Emission Of Electromagnetic Radiation By Superluminal Polarization Currents, Andrea Caroline Schmidt-Zweifel Dec 2020

Theoretical And Experimental Studies Of The Emission Of Electromagnetic Radiation By Superluminal Polarization Currents, Andrea Caroline Schmidt-Zweifel

Electrical and Computer Engineering ETDs

Maxwell’s equations establish that patterns of electric charges and currents can be animated to travel faster than the speed of light in vacuo, c, and that these superluminal distribution patterns emit tightly focused packets of electromagnetic radiation that are fundamentally different from the emissions by previously known sources -- on Earth and in the Universe. This dissertation introduces a practical faster-than-light emitter: The superluminal polarization current antenna. Such devices use a polarization current that travels faster than c to give rise to electromagnetic radiation, a technique known as the vacuum Čerenkov effect. In what is to follow, the theoretical and …


Integrating Deep Learning And Augmented Reality To Enhance Situational Awareness In Firefighting Environments, Manish Bhattarai Nov 2020

Integrating Deep Learning And Augmented Reality To Enhance Situational Awareness In Firefighting Environments, Manish Bhattarai

Electrical and Computer Engineering ETDs

We present a new four-pronged approach to build firefighter's situational awareness for the first time in the literature. We construct a series of deep learning frameworks built on top of one another to enhance the safety, efficiency, and successful completion of rescue missions conducted by firefighters in emergency first response settings. First, we used a deep Convolutional Neural Network (CNN) system to classify and identify objects of interest from thermal imagery in real-time. Next, we extended this CNN framework for object detection, tracking, segmentation with a Mask RCNN framework, and scene description with a multimodal natural language processing(NLP) framework. Third, …


Health Monitoring Using Deep Learning Of Acoustic And Speech Signals, Eric E. Hamke Nov 2020

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). …


Incentivization In Mobile Edge Computing Using A Full Bayesian Approach, Sean Lebien Nov 2020

Incentivization In Mobile Edge Computing Using A Full Bayesian Approach, Sean Lebien

Electrical and Computer Engineering ETDs

The advances of multi-access edge computing (MEC) have paved the way for the integration of the MEC servers, as intelligent entities into the Internet of Things (IoT) environment as well as into the 5G radio access networks. In this thesis, a novel artificial intelligence-based MEC servers’ activation mechanism is proposed, by adopting the principles of Reinforcement Learning (RL) and Bayesian Reasoning. The considered problem enables the MEC servers’ activation decision-making, aiming at enhancing the reputation of the overall MEC system, as well as considering the total computing costs to serve efficiently the users’ computing demands, guaranteeing at the same time …


Artificial Intelligence Enabled Distributed Edge Computing For Internet Of Things Applications, Georgios Fragkos Nov 2020

Artificial Intelligence Enabled Distributed Edge Computing For Internet Of Things Applications, Georgios Fragkos

Electrical and Computer Engineering ETDs

Artificial Intelligence (AI) based techniques are typically used to model decision-making in terms of strategies and mechanisms that can conclude to optimal payoffs for a number of interacting entities, often presenting competitive behaviors. In this thesis, an AI-enabled multi-access edge computing (MEC) framework is proposed, supported by computing-equipped Unmanned Aerial Vehicles (UAVs) to facilitate Internet of Things (IoT) applications. Initially, the problem of determining the IoT nodes optimal data offloading strategies to the UAV-mounted MEC servers, while accounting for the IoT nodes’ communication and computation overhead, is formulated based on a game-theoretic model. The existence of at least one Pure …


Socio-Physical Human Orchestration In Smart Cities, Nathan Patrizi Oct 2020

Socio-Physical Human Orchestration In Smart Cities, Nathan Patrizi

Electrical and Computer Engineering ETDs

In this thesis, we present a novel socio-physical human orchestration framework to deal with the increasing complexity of smart city environments, by capitalizing on recent advances in game theory and reinforcement learning, with the goal of solving the efficient management of a smart city while improving the quality of life for the humans living in said smart city. This problem has become more challenging as the smart cities have become more complicated and complex with new technologies. In the proposed framework, each human selects a Point of Interest (PoI) that it wants to visit. This selection is performed by acting …


Secondary Electron Yield Measurements On Materials Of Interest To Vacuum Electron Communication Devices, Talal Ahmed Malik Jul 2020

Secondary Electron Yield Measurements On Materials Of Interest To Vacuum Electron Communication Devices, Talal Ahmed Malik

Electrical and Computer Engineering ETDs

Microwave vacuum electron devices are a critical part of communication satellite payloads. The phenomenon of multipactor breakdown (MPB) can cause the performance of these devices to deteriorate, including their partial or total destruction. MPB depends on a number of factors, including the secondary electron yield (SEY) of materials used within the device. The process of electron multiplication, which leads to breakdown, initiates with the impact of primary electrons on target surfaces, and the resonance of free electrons within an oscillating electromagnetic field under vacuum conditions. Therefore, it is of interest to find materials and surface treatment methods that exhibit low …


Advanced Parallel Algorithms In Computational Electromagnetics, Shu Wang Jul 2020

Advanced Parallel Algorithms In Computational Electromagnetics, Shu Wang

Electrical and Computer Engineering ETDs

The rapid development of high performance computing has pushed the computational electromagnetic(CEM) towards high accuracy, high fidelity and extreme computational scales. There is a great need for existing CEM solvers to have enhanced parallelism and scaling capability. The purpose of this dissertation is to investigate advanced parallel algorithms for both frequency and time domain solvers.

In frequency domain, this work first develop the underpinnings of parallel preconditioning technique and high-order transmission condition in the context of multi-solver scheme. The result is a computing resource-aware and implementation wise compact solver. Then this work targeted at developing efficient algorithms for cases where …


Software Execution Under Extreme Electromagnetic Interference, Luis Ariel Valbuena Reyes Jul 2020

Software Execution Under Extreme Electromagnetic Interference, Luis Ariel Valbuena Reyes

Electrical and Computer Engineering ETDs

Software routines that deviate from the original algorithm’s goal due to a perturba- tion agent is a phenomenon that has been observed for a long time now. From unin- tended executions on flight control computers during the dawn of space exploration, passing through hardware Trojans tampering in corporate security, to sensitive med- ical equipment compromised to the point of changing the amount of delivered drug, the time intervals, and the reported biomedical measured data, such intrusions are a major risk challenging society. In this dissertation, a computer under perturbation is modeled by a hybrid sys- tem that captures the digital …


Device-Level Predictive Modeling Of Extreme Electromagnetic Interference, Nishchay H. Sule Jul 2020

Device-Level Predictive Modeling Of Extreme Electromagnetic Interference, Nishchay H. Sule

Electrical and Computer Engineering ETDs

Radio Frequency (RF) interference is a prominent issue for modern electronic devices. As device size and supply power shrink to meet the on-going demand for compact and complex Integrated Circuits (ICs), their susceptibility to external noise coupling to the input or power supply increases significantly. One such type of noise that acts upon a system to be considered is Extreme Electromagnetic Interference (EEMI). Previous works done to understand and evaluate the impact of EEMI onto a system or sub-system have been conducted on a statistical or empirical analysis level, which has led to complex and convoluted analysis, that requires significant …


Early Time (E1) High Altitude Electromagnetic Pulse Effects On Lightning Surge Arresters And Trip Coils, David Erney Sanabria Jul 2020

Early Time (E1) High Altitude Electromagnetic Pulse Effects On Lightning Surge Arresters And Trip Coils, David Erney Sanabria

Electrical and Computer Engineering ETDs

A High Altitude Electromagnetic Pulse (HEMP) is a potential threat to the power grid. HEMP can couple on transmission lines causing large overvoltages, which could be harmful to the line and everything else connected to it. The effects of overvoltages on all sorts of devices in the power grid need to be understood. The work developed here is a joint effort between The University of New Mexico and Sandia National Laboratories; The devices that are within the scope of this effort are Trip Coils and Lightning Surge Arresters (LSA). Existing data on HEMP, existing standards, and a previous analysis, were …


Adaptive Encoding For Constrained Video Delivery In Hevc, Vp9, Av1 And Vvc Compression Standards And Adaptation To Video Content, Gangadharan Esakki Jul 2020

Adaptive Encoding For Constrained Video Delivery In Hevc, Vp9, Av1 And Vvc Compression Standards And Adaptation To Video Content, Gangadharan Esakki

Electrical and Computer Engineering ETDs

The dissertation proposes the use of a multi-objective optimization framework for designing and selecting among enhanced GOP configurations in video compression standards. The proposed methods achieve fine optimization over a set of general modes that include: (i) maximum video quality, (ii) minimum bitrate, (iii) maximum encoding rate (previously minimum encoding time mode) and (iv) can be shown to improve upon the YouTube/Netflix default encoder mode settings over a set of opposing constraints to guarantee satisfactory performance. The dissertation describes the implementation of a codec-agnostic approach using different video coding standards (x265, VP9, AV1) on a wide range of videos derived …


Integration Of Machine Learning For Reactive Power Control For A Distribution Feeder Simulation With External Load, Ivonne D. Acosta Molina May 2020

Integration Of Machine Learning For Reactive Power Control For A Distribution Feeder Simulation With External Load, Ivonne D. Acosta Molina

Electrical and Computer Engineering ETDs

It has been 32 years since the Brundtland Report was published. That was the first time that the term Sustainable Development (SD) was coined. In this context, renewable sources of energy play an important role on not to deplete our natural resources in order to meet our need without compromising future generations. Smart Grids are on the pathway to achieve the SD goals. This Thesis focuses on the integration of renewables, specifically Solar PV panels and inverters and its interactions with the distribution grid. Since the power injection caused by the PV inverter can alter the voltage range, Reinforcement Learning …


Advancing Compact Pulsed Power, Jon C. Pouncey Apr 2020

Advancing Compact Pulsed Power, Jon C. Pouncey

Electrical and Computer Engineering ETDs

The first two decades of the 21st century have seen significant interest in expanding the application of pulsed power technology beyond its traditional use in physics and nuclear weapons research. Applications in the field of national defense, which present unique constraints on system size, have provided impetus to increase the exploration of compact pulsed power solutions. Innovations related to energy density, insulation, switching, and power conversion systems have been realized, bringing deployable compact pulsed power systems closer to realization than ever before. However, recent systems integration efforts have shown that work still remains to develop needed tools and technologies …


Optimal Relay Location In A Microgrid Using Optimization Techniques, Benjamin J. Reimer Apr 2020

Optimal Relay Location In A Microgrid Using Optimization Techniques, Benjamin J. Reimer

Electrical and Computer Engineering ETDs

This thesis paper proposes an optimal relay placement approach for microgrids. The algorithm separately calculates the System Average Interruption Frequency Index (SAIFI) of a microgrid in both grid-connected and islanded microgrid modes. The objective is to find the optimal relay locations such that the microgrid overall SAIFI is minimized. The power electronics interfaces associated with distributed energy resources may be classified as grid following or grid forming. As opposed to grid-following distributed energy resources (DERs) such as typical solar inverters, grid-forming inverters can control the microgrid voltage and frequency at the point of their interconnection. Therefore, these DERs can facilitate …


Advancing Elastic Solid Dynamics In Computer Graphics, Ran Luo Apr 2020

Advancing Elastic Solid Dynamics In Computer Graphics, Ran Luo

Electrical and Computer Engineering ETDs

This dissertation proposes novel algorithms and applications and provides a real-time and easy-to-use simulator for realistic animation of the 3D solid model. The Finite Element Method (FEM) is a popular tool in the community because of its accurate result, however, the FEM is computationally expensive to handle a large number of DOFs. We present novel techniques to combine linear and nonlinear elasticity with model reduction to provide fast and realistic animation. On the other hand, one of the most important computation tasks of solid simulation is to evaluate the gradient vector and Hessian matrix of elastic energy function. We present …


Physical Unclonable Functions Based On Delay Paths And An Interdigital Microstrip Notch Filter, Mitch Martin Apr 2020

Physical Unclonable Functions Based On Delay Paths And An Interdigital Microstrip Notch Filter, Mitch Martin

Electrical and Computer Engineering ETDs

A Physical Uncloneable Function (PUF) is an integrated circuit hardware primitivethat is designed to leverage naturally occurring variations to produce a randombitstring. The Aribiter (ARB) PUF is one of the first to be described in the literature.It derives its entropy from variations that occur in the delays of identically configuredlogic paths. The ARB PUF uses a phase comparator to decide which path of a pairis faster under a given challenge, and generates a 0 or 1 as a response indicatorbit. Unfortunately, the ARB PUF is not reliable, requiring error correction in caseswhere the sequence of response bits (the bitstring) needs …


Tunneling And Transport Properties Of Organic And Inorganic Thin Film, Farhana Anwar Mar 2020

Tunneling And Transport Properties Of Organic And Inorganic Thin Film, Farhana Anwar

Electrical and Computer Engineering ETDs

In this article I provide a new method for computing electronic transport properties of graphene i.e. the peculiar tunneling properties of two-dimensional massless Dirac electrons. I consider a simple situation : a massless Dirac electron incident on a potential barrier which is tilted by applied bias and use finite difference method to obtain transmission probability(without involving transfer matrix). In the presence of an applied bias transmission coefficient and tunneling current were obtained and the effect of electric field which modulates the barrier profile therefore conductivity pattern were explained. Furthermore, this method can also be applied to investigate transport properties of …


Inhibiting Surface Flashover In Vacuum With High Gradient Insulators, Cameron Harjes Feb 2020

Inhibiting Surface Flashover In Vacuum With High Gradient Insulators, Cameron Harjes

Electrical and Computer Engineering ETDs

In high voltage systems, insulators may be used to separate conductors and these insulators are typically the limiting factor in the system’s operating voltage. When the voltage between two conductors is too large, the insulators can fail due to surface flashover. As systems become more compact, the threat of failure by insulator flashover increases, making the optimization of insulators a critical task for reliability.

Insulators at a vacuum interface are especially vulnerable to surface flashover. Insulators have been shown to holdoff more voltage in vacuum after being baked to remove imbedded surface gases. Ceramic materials are particularly attractive because, unlike …