Engineering Commons^™

Machine Learning Applications In Power Systems, Xinan Wang

Electrical Engineering Theses and Dissertations

Machine learning (ML) applications have seen tremendous adoption in power system research and applications. For instance, supervised/unsupervised learning-based load forecasting and fault detection are classic ML topics that have been well studied. Recently, reinforcement learning-based voltage control, distribution analysis, etc., are also gaining popularity. Compared to conventional mathematical methods, ML methods have the following advantages: (i). better robustness against different system configurations due to its data-driven nature; (ii). better adaption to system uncertainties; (iii). less dependent on the modeling accuracy and validity of assumptions. However, due to the unique physics of the power grid, many problems cannot be directly solved …

Application Of Optimal Switching Using Adaptive Dynamic Programming In Power Electronics, Ataollah Gogani Khiabani

Mechanical Engineering Research Theses and Dissertations

In this dissertation, optimal switching in switched systems using adaptive dynamic programming (ADP) is presented. Two applications in power electronics, namely single-phase inverter control and permanent magnet synchronous motor (PMSM) control are studied using ADP. In both applications, the objective of the control problem is to design an optimal switching controller, which is also relatively robust to parameter uncertainties and disturbances in the system. An inverter is used to convert the direct current (DC) voltage to an alternating current (AC) voltage. The control scheme of the single-phase inverter uses a single function approximator, called critic, to evaluate the optimal cost …

Control And Locomotion Of Inertially And Magnetically Actuated Multi-Scale Robotic Systems, Ehab Al Khatib

Mechanical Engineering Research Theses and Dissertations

In this research, two actuation systems were introduced, inertial and magnetic actuation. In the inertial actuation, the robot used the transfer of momentum to navigate, and this momentum could be generated by spinning masses and wheels. Recent studies in our System Laboratory proved that a wide range of inertially actuated locomotion systems could be generated. This can be achieved by using a family tree approach, starting from a very simple system, and progressively evolving it to more complex ones. The motion diversity of these robots inspired us to extend their locomotion from a macro scale to millimeter and micro scales. …

Design Of A Drone-Flight-Enabled Wireless Isolation Chamber, John Wensowitch

Electrical Engineering Theses and Dissertations

The next wave of drone applications is moving from repeatable, single-drone activities such as evaluating propagation environments to team-based, multi-drone objectives such as drone-based emergency services. In parallel, testbeds have sought to evaluate emerging concepts such as highly-directional and distributed wireless communications. However, there is a lack of intersection between the two works to characterize the impact of the drone body, antenna placement, swarm topologies, and multi-dimensional connectivity needs that require in-flight experimentation with a surrounding testbed infrastructure. In this work, we design a drone-flight-enabled isolation chamber to capture complex spatial wireless channel relationships that drone links experience as applications …

Heuristic-Based Threat Analysis Of Register-Transfer-Level Hardware Designs, Wesley Layton Ellington

Electrical Engineering Theses and Dissertations

The development of globalized semiconductor manufacturing processes and supply chains has lead to an increased interest in hardware security as new types of hardware based attacks, called hardware Trojans, are being observed in industrial and military electronics. To combat this, a technique was developed to help analyze hardware designs at the register-transfer-level (RTL) and locate points of interest within a design that might be vulnerable to attack. This method aims to eventually enable the creation of an end-to-end design hardening solution that analyzes existing designs and suggests countermeasures for potential Trojan attacks. The method presented in this work uses a …

Technology-Dependent Quantum Logic Synthesis And Compilation, Kaitlin Smith

Electrical Engineering Theses and Dissertations

The models and rules of quantum computation and quantum information processing (QIP) differ greatly from those that govern classical computation, and these differences have caused the implementation of quantum processing devices with a variety of new technologies. Many platforms have been developed in parallel, but at the time of writing, one method of quantum computing has not shown to be superior to the rest. Because of the variation that exists between quantum platforms, even between those of the same technology, there must be a way to automatically synthesize technology-independent quantum designs into forms that are capable of physical realization on …

Reducing The Production Cost Of Semiconductor Chips Using (Parallel And Concurrent) Testing And Real-Time Monitoring, Qutaiba Khasawneh

Electrical Engineering Theses and Dissertations

Consumer electronics changed the semiconductor industry by developing many new challenges for consumer products. One of the main challenges in the consumer product is that it propelled the volume of production to massive production, e.g. hundreds of millions of cell phones are produced yearly. Combined with the overproduction of consumer products, price pressure is another challenge for consumer products. Many of the new techniques used in the design and fabrication enabled the integration of more devices in the same chips. This reduced the cost of the chips, lowered the power consumption, increased the circuit operation speed, enabled more reliable implementation, …

Resource Allocation And Task Scheduling Optimization In Cloud-Based Content Delivery Networks With Edge Computing, Yang Peng

Operations Research and Engineering Management Theses and Dissertations

The extensive growth in adoption of mobile devices pushes global Internet protocol (IP) traffic to grow and content delivery network (CDN) will carry 72 percent of total Internet traffic by 2022, up from 56 percent in 2017. In this praxis, Interconnected Cache Edge (ICE) based on different public cloud infrastructures with multiple edge computing sites is considered to help CDN service providers (SPs) to maximize their operational profit. The problem of resource allocation and performance optimization is studied in order to maximize the cache hit ratio with available CDN capacity.

The considered problem is formulated as a multi-stage stochastic linear …

Feedback Mechanisms For Centralized And Distributed Mobile Systems, Yan Shi

Electrical Engineering Theses and Dissertations

The wireless communication market is expected to witness considerable growth in the immediate future due to increasing smart device usage to access real-time data. Mobile devices become the predominant method of Internet access via cellular networks (4G/5G) and the onset of virtual reality (VR), ushering in the wide deployment of multiple bands, ranging from TVWhite Spaces to cellular/WiFi bands and on to mmWave. Multi-antenna techniques have been considered to be promising approaches in telecommunication to optimize the utilization of radio spectrum and minimize the cost of system construction. The performance of multiple antenna technology depends on the utilization of radio …

Leveraging Geographical And Spectral Information For Efficient Cellular Systems, Matthew Tonnemacher

Electrical Engineering Theses and Dissertations

With the unprecedented increase in mobile data demand and limited usable spectrum to provide for it, a paradigm shift towards spectrum sharing is a promising solution. However, there are many challenges that limit current spectrum sharing practices. One challenge is that proper spectrum sharing requires engaging devices to have an understanding of the impact they have on the ecosystem while transmitting in terms of spacial interference footprint and the implications to devices in their interference range. Another is that operators, especially licensed ones, have strict quality of service requirements for their subscribers, discouraging them from allowing unlicensed access of their …

Investigation Of The Electrode Polarization Effect For Biosensor Applications, Anil Koklu

Mechanical Engineering Research Theses and Dissertations

My research focuses on electrokinetic transport. Particularly, in this dissertation, we focus on fabrication and testing of micro electrodes with nanostructured surfaces to minimize the electrode polarization (EP) effects for biosensor applications. In the first study, electrochemical deposition of gold nanoparticles on to planar gold electrodes was used to generate rough surfaces. Dendritic nanostructures that reduced EP up to two orders of magnitude was obtained by optimizing the deposition conditions. These structures also enhanced dielectrophoresis (DEP) response of our bio-chips, making them usable in physiological buffers. In further studies we discovered a universal scaling of EP in the frequency domain, …

Design And Control Of Fiber Encapsulation Additive Manufacturing, Matt Saari

Mechanical Engineering Research Theses and Dissertations

This work presents the design, development, and analysis of the Fiber Encapsulation Additive Manufacturing (FEAM) system developed at the Laboratory for Additive Manufacturing Robotics \& Automation at the Lyle School of Engineering at Southern Methodist University. The innovation introduced by FEAM is the ability to insert a continuous fiber of different material into the flowing extrudate. Correctly positioning the fiber feed inside the extrudate while turning the fiber in arbitrary directions is a critical aspect of the technology. This will allow for the full exploitation of the capabilities of the FEAM technology to produce robotic components that actuate and sense. …

Operation And Planning Of Data Centers In Electricity Networks, Ali Vafamehr

Electrical Engineering Theses and Dissertations

Cloud computing provides unique opportunities for the various sectors of the economy such as the automotive industry, education, finance, and governmental entities. In-house IT infrastructures vary in quality and can often be outdated and ineffective. As an alternative, cloud computing is a popular IT model which allows various businesses to “outsource” the IT infrastructure to a more efficient model. Businesses are opting to use cloud computing in order to eliminate the capital expenses of traditional IT systems and reduce the around-the-clock expert manpower required to operate on-site IT infrastructures. Relying on cloud services gives businesses the flexibility to access a …

Wireless Channel Characterization Based On Crowdsourced Data And Geographical Features, Rita Enami

Electrical Engineering Theses and Dissertations

To design and plan wireless communication systems, an accurate propagation estimate is required of a deployment region. Propagation prediction models consist of two types of fading: large-scale and small-scale fading. With large-scale fading, the path loss information is crucial for cell planning, coverage estimation, and optimization. With small-scale fading, the statistical fluctuation on the local variations of the average signal level can have a dramatic effect on protocol decisions and resulting performance. To obtain accurate estimates of both types of fading, typically field measurements are needed that use drive testing, which is expensive in terms of time and cost. Recently, …

Optical Micro-Seismometer Based On Evanescent Field Perturbation Of Whispering Gallery Modes, Jaime Da Silva

Mechanical Engineering Research Theses and Dissertations

This thesis proposes a light-weight, compact, and accurate optical micro-seismometer that could be used in many applications, such as planetary exploration. The sensor proposed here is based on the principle of whispering gallery optical mode (WGM) resonance shifts of a dielectric micro-resonator due to disturbances of its evanescent field. The micro-seismometer could be used in place of the traditional bulky seismometers. The design of a waveguide-resonator and mechanical structure to disturb the evanescent field are presented. A proof-of-concept a seismometer model that uses a 5µm ring resonator is numerically tested with actual seismic data. The results show that a WGM-based …

Accurate Vehicle Detection Using Multi-Camera Data Fusion And Machine Learning, Hao Wu

Electrical Engineering Theses and Dissertations

Computer-vision methods have recently been extensively used in intelligent transportation systems for vehicle detection. However, the detection of severely occluded or partially observed vehicles due to the limited camera fields of view remains a significant challenge. This paper presents a multi-camera vehicle detection system that significantly improves the detection performance under occlusion conditions. The key elements of the proposed method include a novel multi-view region proposal network that localizes the candidate vehicles on the ground plane. We also infer the vehicle occupancies by leveraging multi-view cross-camera context. Experiments are conducted on a dataset captured from a roadway in Richardson, TX, …

A Novel Ultrasound Imaging Technique Using Random Signals, Anahita Khalilzadeh

Electrical Engineering Theses and Dissertations

Ultrasound imaging has been used extensively because of its benign nature and relatively low cost implementation. The most common approach for forming an image is Brightness Mode (B-Mode), which uses an array with dynamic focusing. Focus is performed through Phase Shifters that are bulky and complicated components which increases the device cost.

This research describes a new method to form an Ultrasound image, without relying on phase shifting. The proposed method offers a lower cost solution compared to the B-Mode systems and overcomes some of their inherent limitations.

Using Gs/S Adc To Evaluate The Emi Of Gan-Based Power Devices, Chi Zhang

Electrical Engineering Theses and Dissertations

As the silicon-based power devices are gradually reaching their performance limits, new power transistors such as Silicon Carbide (SiC) and Gallium Nitride (GaN) FETs have been rapidly developed in recent years. GaN devices have been widely accepted by researchers for its higher speed and efficiency than silicon power devices. However, despite all its merits, the GaN device faces a more severe problem of electromagnetic interference (EMI) than the silicon device due to its high performance. Various control techniques of EMI have been studied so far and many of them require the evaluation of EMI. Research shows that the EMI level …

Standing-Wave Dielectric Array Antennas, Ayman Althuwayb

Electrical Engineering Theses and Dissertations

Due to the evolutions in wireless communication systems, antenna engineers have been confronting a number of challenges regarding improving the performance of antennas, miniaturizing the size as well as considering the fabrication simplicity. Although dielectric resonator antennas typically suffer from exhibiting low gain, they have been thoroughly under investigating as they are being excellent candidates to be utilized to fulfill contemporary communication systems requirements and specifications, especially at high-frequency ranges. The reason behind this solicitude is because they have several advantageous features, including but not limited to the simplicity of the used excitation mechanism and fabrication easiness.

One of the …

Indirect Imaging Using Computational Imaging Techniques, Aparna Viswanath

Electrical Engineering Theses and Dissertations

The work describes various methods employed towards solving the problem of indirect imaging. Computational techniques are employed to indirectly decipher information about an object hidden from view of a camera. Notion of virtualizing the source of illumination and detectors on real world rough surfaces was exploited to construct a non line of sight computational imager. Diversity was explored from the stand point of both illumination of the object and imaging of light reflected from the object. To understand the impact of scattering by real world rough surfaces, an instrument was developed that allows characterization of isoplanatic angle for different surface …

Investigating The Effect Of Detecting And Mitigating A Ring Oscillator-Based Hardware Trojan, Lakshmi Ramakrishnan

Electrical Engineering Theses and Dissertations

The outsourcing of the manufacturing process of integrated circuits to fabrications plants all over the world has exposed these chips to several security threats, especially at the hardware level. There have been instances of malicious circuitry, such as backdoors, being added to circuits without the knowledge of the chip designers or vendors. Such threats could be immensely powerful and dangerous against confidentiality, among other vulnerabilities.

Defense mechanisms against such attacks have been probed and defense techniques have been developed. But with the passage of time, attack techniques have improved immensely as well. From directly observing the inputs or outputs, adversaries …

Indirect Imaging Using Heterodyne Remote Digital Holography, Muralidhar Madabhushi Balaji

Electrical Engineering Theses and Dissertations

Conventional line-of-sight imaging techniques rely on detecting light paths bouncing from the object and reaching directly to the detector. Absence of any such direct light paths from object to detector results in a failure to recover any useful information using conventional techniques. The absence of direct light paths from object to detector can be observed in several real-world scenarios such as looking around a corner, imaging through turbid media, imaging through tissue etc.

The focus of this thesis is pertaining to the problem of looking around corners (or) imaging object hidden from line of sight at macroscopic scales. This thesis …

A Comparative Analysis Of Integrated Optical Waveguide Isolators With Magneto-Optic Layers, Reyhane Oztekin

Electrical Engineering Theses and Dissertations

The objective of this study is to theoretically devise an on-chip optical isolator which is monolithically integrated with a semiconductor waveguide layer yielding low loss. The optical properties of iron are modeled for the use of optical waveguide isolators by improving the Brendel-Bormann model. Our model for iron shows excellent fit with the optical data up to 30 electronvolts (eV). The semiconductor optical waveguide isolator with magneto-optic layers based on non-reciprocal loss shift is developed in this study. Fe, Co, and Ni metals as well as cerium-substituted yttrium iron garnet (Ce:YIG) have been used as magneto-optic layers. We have shown …

Subspace Averaging Of Auditory Evoked Potentials, Xiaoliang Wang

Electrical Engineering Theses and Dissertations

The auditory evoked potential (AEP) is an electric potential generated in the brain in response to auditory stimuli. It has clinical importance in the detection of newborn infant hearing loss. The signal to noise ratio (SNR) of the AEP is low, so signal averaging is typically employed to estimate it. Often, thousands of trials must be averaged before a sufficiently high SNR estimate is obtained.

In this research, we have developed a new AEP averaging method called subspace averaging. The subspace averaging method projects onto the signal subspace: the span of the principal eigenvectors of the signal correlation matrix. The …

Linear Phase Multi-Frequency Notch Filter Via Quadratic Programming, Yueran Ma

Electrical Engineering Theses and Dissertations

Discrete-time notch filters can be divided into infinite impulse response (IIR) and finite impulse response (FIR) notch filters. Infinite impulse response notch filters are easy to design and implement but suffer from nonlinear phase characteristics and unacceptable startup transients. Finite impulse response filters on the other hand can be designed to have linear phase but require more coefficients to achieve narrow notch widths. Multiple frequency FIR notch filters that can effectively reject several selected spectral regions while providing high transmission at frequencies outside the rejected regions have applications in communication systems, radar systems and biomedical signal processing.

A new multi-frequency …

Cell-Aware Fault Analysis And Test Set Optimization In Digital Integrated Circuits, Fanchen Zhang, Jennifer Dworak

Computer Science and Engineering Theses and Dissertations

Structural tests have many advantages over functional patterns. The fault coverage of structural patterns is generally higher and easier to quantify, well-known algorithms are available to generate them, and they are often a much easier choice for debugging and diagnosis. However, depending on the fault models used, traditional structural patterns can still miss many defects, such as the defects that may occur inside the standard cells, and when chips are placed on a board, they may fail in functional mode even if they pass all structural tests. This can happen even if those same structural tests are applied in-system on …

Computational Theories For Human Stereo Vision, Han Gao

Electrical Engineering Theses and Dissertations

Binocular stereopsis refers to the ability to perceive depth, which has always been a central problem in perception since the time of da Vinci. The foremost theoretical difficulty that arises when attempting to understand how the visual system computes disparity is known as the correspondence or matching problem. Decades of research upon macaque primary visual cortex has shown that in each layer of the primary visual cortex (V1) long-range horizontal connections among striate cortex cells exist which integrate information from different parts of the visual field. Inspired by long-range horizontal connections in V1 and the Jeffress model, a time-delay neural …

High-Speed Single-Channel Sar Adc Using Coarse And Fine Comparators With Background Comparator Offset Calibration, Guanhua Wang

Electrical Engineering Theses and Dissertations

A 1-GS/s 8-bit single-channel successive-approximation-register (SAR) analog-to-digital converter (ADC) using coarse and fine comparators with fully background comparator offset calibration is presented. Low-power coarse comparators and low-noise fine comparators are both employed to improve the comparator power efficiency. Non-binary digital-to-analog converter (DAC) with redundancy is employed to tolerate possible errors in the most-significant-bit (MSB) decisions. A novel comparator offset calibration scheme is proposed to remove the offsets between the different comparators, without slowing down the speed of the SAR conversion. The prototype ADC is simulated in a 28 nm CMOS technology and achieves an SNDR of 42.13 dB near Nyquist …

Designing Smart-Grid Telecommunications Systems Via Interval Flow Network Optimization, Anthony J. Klinkert

Operations Research and Engineering Management Theses and Dissertations

One of the first major, widespread deployments of an Internet of Things (IoT) system is an electric utility’s smart-grid communications network. Communication networks support utility smart-grids for an electrical power provider by linking industrial IoT devices on the grid, such as residential and commercial customers’ electric meters to the utility’s data center. A new solution methodology and software tool is applied to the optimization of an electric utility smart-grid communications network. This research provides utilities with a technique to reduce cost of new and current communications networks for smart-grid programs. This research introduces the use of a new advanced optimization …

Microgrids: Resilience, Reliability, And Market Structure, Saeed Dehghan Manshadi

Electrical Engineering Theses and Dissertations

This dissertation addresses several challenges corresponding to the operation and planning of microgrids in distribution networks including the formation, energy supply resilience, the contribution of microgrids in the short-term and mid-term operation of bulk power networks and the computational challenges in operation of interdependent infrastructure systems.

An approach to transforming the active distribution network with distributed energy resources into multiple autonomous microgrids is presented in the first section. The distribution network consists of several generation resources and demand entities that could be clustered into autonomous microgrids. Eigen decomposition in the graph spectra of the distribution network is leveraged to determine …