Engineering Commons^™

Autonomous Decision-Making In Interdependent Computing Systems Based On Artificial Intelligence, Georgios Fragkos

Electrical and Computer Engineering ETDs

With the advent of Artificial Intelligence (AI), the notion of autonomy, in terms of acting and thinking based on personal experience and judgment, has paved the way towards an autonomous decision-making future. This future can address the complex domain of the interdependent computing systems, whose main challenge is that they interact with each other with unpredictable and often unstable outcomes. It is crucial to envision and design this AI-driven autonomy for the reciprocal computing systems which cover a variety of use-cases ranging from the Internet of Things (IoT) to cybersecurity. This can be achieved by cloning the human decision-making process, …

Stochastic Optimal Shared Control With Non-Gaussian Processes, Paul Onor

Electrical and Computer Engineering ETDs

In this paper, we propose an approach for shared control of a planar quadrotor that allows for non-Gaussian disturbance in the model and non-Gaussian variation in the pilot's control actions. We do this by constructing empirical characteristic functions for the state, inputs, and disturbance using demonstrations by a human expert. These are then used to make predictions of future states and of the system disturbance, using the first and second moments of the empirical characteristic function to estimate the mean and variance of these processes. With this method, we can extend assumptions from additive white Gaussian noise to any real-valued …

A Study On Electromagnetic Topology Optimization Using Binary Particle Swarm Algorithm, Mohammad Sazzad Hossain

Electrical and Computer Engineering ETDs

Topology optimization is a state-of-the-art tool for detecting the best material layout in a physical space to obtain certain goals. Initially developed as a structural engineering tool, it has been recently used in electromagnetics and has shown immense potential. The aim of this work is to build a framework for applying the topology optimization method in electromagnetics using a modified binary particle swarm optimization (BPSO) algorithm. In this thesis, a very classic problem of coax to waveguide transition has been considered, and a novel solution has been given using topology optimization. The steps to implementing topology optimization using BPSO have …

The Corona-To-Spark Transition And Its Dependence On Electric Field Non-Uniformity, David O. Smith

Electrical and Computer Engineering ETDs

The corona to spark transition is an important part of understanding gaseous breakdown in non-uniform fields. The degree of uniformity in the geometry determines both the onset of corona as well as the eventual spark transition. In a highly non-uniform geometry, the onset of corona precedes the development of a spark. However, in weakly non-uniform fields, corona is unable to form before it transitions into a spark. The degree of non-uniformity at which this transition occurs is known as the corona point.

An experimental setup using the point electrodes allows precise changes in field uniformity, characterizing the corona point in …

Decentralized Intelligent Decision Making In Cyber Physical Social Systems, Nathan Patrizi

Electrical and Computer Engineering ETDs

The accelerated evolution towards jointly considering the physical, cyber, and social space is expected to dramatically increase the interest of the research and industrial community to build efficient, resilient, and secure Cyber Physical Social Systems. In this dissertation, we focus our research activities on devising decentralized intelligent decision making models, frameworks, and algorithms to support the smooth operation of Cyber Physical Social Systems. The proposed decentralized intelligent decision making models are jointly exploiting theories from the field of Economics, such as Game Theory and Contract Theory, and from the field of Computer Science, such as Reinforcement Learning concepts. Reinforcement learning …

Application Of Machine Learning For Predicting Iemi Upset In Multi-Architecture Microcontrollers, Daniel S. Guillette

Electrical and Computer Engineering ETDs

Four microcontrollers were programmed to execute a simple counting program. Pulsed RF signals – also known as Intentional ElectroMagnetic Interference (IEMI) – were injected into the clock input of the microcontrollers. At the same time, the output lines were monitored to determine whether the IEMI signal altered the output of the counting program – referred to as an upset. A state-of-the-art automated testing apparatus was used to collect and process 120,960 samples of IEMI upset data. The data was used to perform a traditional upset trends study and train a series of machine learning (ML) techniques – k-Nearest Neighbors, Support …

Speaker Diarization And Identification From Single-Channel Classroom Audio Recording Using Virtual Microphones, Antonio Gomez

Electrical and Computer Engineering ETDs

Speaker identification in noisy audio recordings, specifically those from collaborative learning environments, can be extremely challenging. There is a need to identify individual students talking in small groups from other students talking at the same time. To solve the problem, we assume the use of a single microphone per student group without any access to previous large datasets for training.

This dissertation proposes a method of speaker identification using cross-correlation patterns associated to an array of virtual microphones, centered around the physical microphone. The virtual microphones are simulated by using approximate speaker geometry observed from a video recording. The patterns …

Multicarrier Modulation Using Discrete Fractional Fourier Transform, Amir Raeisi Nafchi

Electrical and Computer Engineering ETDs

The focus of the research was to investigate the application of the discrete fractional Fourier transform (DFRFT) in communication systems. We investigated the compactness of the Gauss-Hermite like eigenvectors of the DFRFT and showed how a multi-carrier modulation system could benefit from it. This led to identifying an affine DFRFT. We proved the circular convolution property for the proposed DFRFT. Using this affine transform, we were able to design an orthogonal frequency division multiplexer (OFDM) communication system. In the process of implementing the OFDM, we developed a method for fast computation of the DFRFT using the chirp-z transform. Using the …

Relativistic Magnetron Powered By Electrons In A High-Energy State, Dmitrii Andreev

Electrical and Computer Engineering ETDs

A traditional relativistic magnetron is an efficient, high-power source of cm-wave radiation. Typically, a cathode sits inside the interaction region and produces a quickly expanding cathode plasma. However, rapid radial expansion leads to unwanted frequency drift and pulse shortening. Recently, researchers at Technion, in collaboration with the University of New Mexico, proposed to use a split cathode to form a low-energy “squeezed” state by injecting electrons externally into a potential well and squeezing them with a sufficiently strong magnetic field. Technion’s long-pulse experiments achieved a low-energy state, at the output power and efficiency comparable to a physical cathode inside the …

Intra-Hour Solar Forecasting Using Cloud Dynamics Features Extracted From Ground-Based Infrared Sky Images, Guillermo Terrén-Serrano

Electrical and Computer Engineering ETDs

Due to the increasing use of photovoltaic systems, power grids are vulnerable to the projection of shadows from moving clouds. An intra-hour solar forecast provides power grids with the capability of automatically controlling the dispatch of energy, reducing the additional cost for a guaranteed, reliable supply of energy (i.e., energy storage). This dissertation introduces a novel sky imager consisting of a long-wave radiometric infrared camera and a visible light camera with a fisheye lens. The imager is mounted on a solar tracker to maintain the Sun in the center of the images throughout the day, reducing the scattering effect produced …

Prospect-Theoretic Demand Response Management In Smart Grid Systems, Sean A. Pluemer

Electrical and Computer Engineering ETDs

In smart grid systems, demand response management (DRM) permits the efficient utilization and control of electrical loads. This control is accomplished by modifying the price of electricity or by shifting peak electricity consumption to off-peak periods. This thesis proposes a DRM model composed of multiple utility companies and multiple consumers. Due to the risk caused by the users' excessive power demands, each utility company has the potential for failure. Prospect Theory principles capture the individual consumer's risk-aware behavior. As a result, a multi-leader multi-follower Stackelberg game is introduced, involving the utility companies (leaders) and consumers (followers). The Stackelberg game determines …

Relativistic Magnetron With Diffraction Output And Split Cathode, Artem Kuskov

Electrical and Computer Engineering ETDs

The relativistic magnetron with diffraction output (MDO) is one of the most efficient
microwave sources for sub-100 ns pulses. For pulse widths greater than 100 ns, the microwave production stops due to anode-cathode (A−K) gap closure. In the presence of a solid cathode, the anode and cathode plasmas expand towards each other, shorting the gap. A research team at The Technion Israel Institute of Technology proposed to replace a solid cathode with a split cathode in a magnetron with radial extraction to mitigate gap closure and maximize microwave production from a long pulse generator. Such a cathode geometry comprises an …

Analytical, Simulation, And Experimental Study Of The Generation Of Multiple Beams For Application To A Traveling Wave Tube(Twt), Khandakar Nusrat Islam

Electrical and Computer Engineering ETDs

The traveling wave tube (TWT) has been a reliable conventional vacuum electron device (VED) since the 1940s. Researchers, beginning in the late 1980s, extended the TWT to the relativistic electron beam regime to generate 100s MW power in X-band. Since the mid-1990s there has been little advancement in the field. Recently, the linear theory of a multi-stream TWT was published that showed super-exponential amplification properties. This study describes a novel technique for producing multiple electron beams with energy difference of about 4-31% with comparable currents from a single cathode at a single potential for a multi-stream TWT. This work presents …