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Power Systems Cascading Failure Analysis And Mitigation Using Discrete Events Systems Approach, Wasseem Al Rousan Jan 2022

Power Systems Cascading Failure Analysis And Mitigation Using Discrete Events Systems Approach, Wasseem Al Rousan

Wayne State University Dissertations

A power system cascading failure can propagate through sequential tripping of components in the network. As a result, a complete or partial shutdown may occur. Many models were developed to understand the failure propagation mechanism at a higher abstract level and methods were implemented for failure mitigation. This work introduces a unified framework of modeling and mitigating cascading failures. Based on a Discrete Event Systems (DES) approach, a power system is modeled by an automaton via parallel composition of the sub-models of system components. A modified DES supervisory control (SC) strategies are introduced as a solution to mitigating cascading failures …


Optical Signal Processing With Discrete-Space Metamaterials, Mohammad Moein Moeini Jan 2022

Optical Signal Processing With Discrete-Space Metamaterials, Mohammad Moein Moeini

Wayne State University Dissertations

As digital circuits are approaching the limits of Moore’s law, a great deal of efforthas been directed to alternative computing approaches. Among them, the old concept of optical signal processing (OSP) has attracted attention, revisited in the light of metamaterials and nano-photonics. This approach has been successful in realizing basic mathematical operations, such as derivatives and integrals, but it is difficult to be applied to more complex ones. Inspired by digital filters, we propose a radically new OSP approach, able to realize arbitrary mathematical operations over a nano-photonic platform. We demonstrate this concept for the case of spatial differentiation, image …


High Mobility N-Type Field Effect Transistors Enabled By Wse2/Pdse2 Heterojunctions, Arthur Bowman Iii Jan 2021

High Mobility N-Type Field Effect Transistors Enabled By Wse2/Pdse2 Heterojunctions, Arthur Bowman Iii

Wayne State University Dissertations

Two-dimensional (2D) semiconductors such as transition metal dichalcogenides (TMDs) have emerged as a promising candidate for post-silicon electronics. Few-layer tungsten diselenide (WSe2), a well-studied TMD, has sown high hole mobility and ON/OFF ratio in field effect transistor (FET) devices. But the n-type performance of WSe2 is still quite limited by the presence of a substantial Schottky Barrier. Palladium diselenide, (PdSe2) is a newly discovered TMD that is of interest because of its high electron mobility, and moderate ON/OFF ratios. However, despite its relatively small bandgap, the n-type performance of few-layer PdSe2 FETs has also been limited by a Schottky barrier, …


Secure Automatic Speaker Verification Systems, Muteb Aljasem Jan 2021

Secure Automatic Speaker Verification Systems, Muteb Aljasem

Wayne State University Dissertations

The growing number of voice-enabled devices and applications consider automatic speaker verification (ASV) a fundamental component. However, maximum outreach for ASV in critical domains e.g., financial services and health care, is not possible unless we overcome security breaches caused by voice cloning, and replayed audios collectively known as the spoofing attacks. The audio spoofing attacks over ASV systems on one hand strictly limit the usability of voice-enabled applications; and on the other hand, the counterfeiter also remains untraceable. Therefore, to overcome these vulnerabilities, a secure ASV (SASV) system is presented in this dissertation. The proposed SASV system is based on …


Improved Contacts And Device Performance In Mos2 Transistors Using 2d Semiconductor Interlayers, Kraig Andrews Jan 2020

Improved Contacts And Device Performance In Mos2 Transistors Using 2d Semiconductor Interlayers, Kraig Andrews

Wayne State University Dissertations

The rapid growth of modern electronics industry over the past half-century has been sustained by the continued miniaturization of silicon-based electronics. However, as fundamental limits approach, there is a need to search for viable alternative materials for next-generation electronics in the post-silicon era. Two-dimensional (2D) semiconductors such as transition metal dichalcogenides (TMDs) have attracted much attention due to their atomic thickness, absence of dangling bonds and moderately high carrier mobility. However, achieving low-resistance contacts has been major impediment in developing high-performance field-effect transistors (FETs) based on 2D semiconductors. A substantial Schottky barrier (SB) is often present at the metal/2D-semicondcutor interface, …


Enabling 3d Printing Technologies For Artificial Compound Eye System And Penetrating Neural Probes, Boshen Zhang Jan 2020

Enabling 3d Printing Technologies For Artificial Compound Eye System And Penetrating Neural Probes, Boshen Zhang

Wayne State University Dissertations

3D printing has become a useful and transformative method and has applications in many different fields, including organ printing, aerospace applications, and medical devices. With higher resolution, faster production speed, and more design flexibility, 3D printing technologies can lead to more novel devices and systems. In this research, two new techniques have been developed to enable 3D printing technologies for artificial compound eye system and penetrating glassy carbon neural electrode array.

This work focuses on developing new applications based on the SLA 3D printing process, which uses the liquid resin to create a solid 3D structure. The limitation of SLA …


Titanium Nitride Nanotube Electrodes Used In Neural Signal Recording Application And Neurotransmitter Detection, Gui Chen Jan 2020

Titanium Nitride Nanotube Electrodes Used In Neural Signal Recording Application And Neurotransmitter Detection, Gui Chen

Wayne State University Dissertations

Electrode probes are devices widely used for stimulating and recording neural cell signals in the neuroscience field, which can convert the ion potential generated by electrochemical activities into an electronic potential that can be measured by the external instrument systems. A stable neural interface that effectively communicates with the nervous system via electrode is much important for the robust recording and the long-term monitoring of the activity of the neural signals. These probes are designed to minimize tissue damage for superior signal quality. Each probe’s mechanical, geometric, and electrical characteristics are precise and highly reproducible for consistent, high-quality results. There …


Error Correction For Automotive Telematics Systems, Samer Zakhem Jan 2020

Error Correction For Automotive Telematics Systems, Samer Zakhem

Wayne State University Dissertations

One benefit of data communication over the voice channel of the cellular network is to reliably transmit real-time high priority data in case of life critical situations. An important implementation of this use-case is the pan-European eCall automotive standard, which has already been deployed since 2018. This is the first international standard for mobile emergency call that was adopted by multiple regions in Europe and the world. Other countries in the world are currently working on deploying a similar emergency communication system, such as in Russia and China. Moreover, many experiments and road tests are conducted yearly to validate and …


Parylene Based Flexible Multifunctional Biomedical Probes And Their Applications, Zhiguo Zhao Jan 2020

Parylene Based Flexible Multifunctional Biomedical Probes And Their Applications, Zhiguo Zhao

Wayne State University Dissertations

MEMS (Micro Electro Mechanical System) based flexible devices have been studied for decades, and they are rapidly being incorporated into modern society in various forms such as flexible electronics and wearable devices. Especially in neuroscience, flexible interfaces provide tremendous possibilities and opportunities to produce reliable, scalable and biocompatible instruments for better exploring neurotransmission and neurological disorders. Of all the types of biomedical instruments such as electroencephalography (EEG) and electrocorticography (ECoG), MEMS-based needle-shape probes have been actively studied in recent years due to their better spatial resolution, selectivity, and sensitivity in chronical invasive physiology monitoring. In order to address the inherent …


An Approach To Evaluate Disability Using Machine Learning And Sensor-Equipped Instruments Demonstrated On Hand Grip Force Data, Prem Kumar Sivakumar Jan 2019

An Approach To Evaluate Disability Using Machine Learning And Sensor-Equipped Instruments Demonstrated On Hand Grip Force Data, Prem Kumar Sivakumar

Wayne State University Dissertations

The goal of this research is to improve the process of rehabilitation. Even though the current tools and technologies are meeting the requirements of clinical use, there is a lot of room for improvement. Improving the tools used in therapy can help reduce costs and save time for the patient and the therapist by giving a valuable insight into the progress of the therapeutic process. Combining therapeutic tools with cognitive tools such as machine learning can assist a therapist to determine and predict functional ability and help patients keep track of their progress.

The long-term goal for instrumented outcome measures …


Learning Models For Corrupted Multi-Dimensional Data: Fundamental Limits And Algorithms, Ishan Jindal Jan 2019

Learning Models For Corrupted Multi-Dimensional Data: Fundamental Limits And Algorithms, Ishan Jindal

Wayne State University Dissertations

Developing machine learning models for unstructured multi-dimensional datasets such as datasets with unreliable labels and noisy multi-dimensional signals with or without missing information have becoming a central necessity. We are not always fortunate enough to get noise-free datasets for developing classification and representation models. Though there is a number of techniques available to deal with noisy datasets, these methods do not exploit the multi-dimensional structures of the signals, which could be used to improve the overall classification and representation performance of the model.

In this thesis, we develop a Kronecker-structure (K-S) subspace model that exploits the multi-dimensional structure of the …


Analysis And Mitigation Of The Impacts Of Delays In Control Of Power Systems With Renewable Energy Sources, Chang Fu Jan 2019

Analysis And Mitigation Of The Impacts Of Delays In Control Of Power Systems With Renewable Energy Sources, Chang Fu

Wayne State University Dissertations

ABSTRACT

Analysis and Mitigation of the Impacts of Delays in Control of Power Systems

with Renewable Energy Sources

by

Chang Fu

Apr. 2019

Advisor : Dr. Caisheng Wang

Major : Electrical and Computer Engineering

Degree : Doctor of Philosophy

With the integration of renewable resources, electric vehicles and other uncertain

resources into power grid, varieties of control topology and algorithms have been proposed to

increase the stability and reliability of the operation system. Load modeling is an critical part

in such analysis since it significantly impacts the accuracy of the simulation in power system,

as well as stability and reliability …


Optical Nanostructures For Controllable And Tunable Optical Properties, Ashfaqul Anwar Anwar Siraji Jan 2019

Optical Nanostructures For Controllable And Tunable Optical Properties, Ashfaqul Anwar Anwar Siraji

Wayne State University Dissertations

Optical nanostructures are heterogeneous media containing subwavelength inclusions in periodic or aperiodic fashion. The optical properties of optical nanostructure can be controlled and tuned using their constituent material properties and spatial arrangement of the inclusions. While optical nanostructures have been widely studied, controllable and tunable nanostructures using low loss transparent materials has not been studied in detail in the literature. The objective of this research is to perform efficient design and analyses of controllable and tunable optical nanostructures using low loss transparent materials.

To that end, versatile and highly accurate numerical methods like finite different tie domain and plane wave …


Developing A Real-World Vehicle Trip Dataset Through Public Travel Surveys And Applying It To Battery Electric Vehicle Performance Study, Nizar Ali Khemri Jan 2019

Developing A Real-World Vehicle Trip Dataset Through Public Travel Surveys And Applying It To Battery Electric Vehicle Performance Study, Nizar Ali Khemri

Wayne State University Dissertations

Real-world second-by-second vehicle driving cycle data is very important for research and development of the traditional fuel-powered vehicles, the emerging electric vehicles, and the hybrid vehicles. A project solely dedicated to generating such information would be extremely costly and time-consuming. Alternatively, we introduce a method to develop such a database by utilizing two publicly available passenger vehicle travel surveys; the 2004-2006 Puget Sound Regional Commission (PSRC) Travel Survey and the 2011 Atlanta Regional Commission (ARC) Travel Survey. The two surveys complement each other – the former is in low time resolution but covers vehicle driving and non-driving operation for over …


Distributed Optimal Power And Voltage Management In Dc Microgrids, Eyad A. Sindi Jan 2019

Distributed Optimal Power And Voltage Management In Dc Microgrids, Eyad A. Sindi

Wayne State University Dissertations

The work developed new control strategies to address fundamental issues of power balance, line loss reduction, and voltage profile management in DC microgrids. In microgrids of distributed renewable generations and controllable loads, load allocation to different distributed generators, line losses, voltage stability and quality are intimately coupled, departing significantly from traditional power grids in which economic dispatch and voltage stability are typically separate control tasks.

In this work, a multi-objective optimization strategy is introduced to address the challenges imposed by these coupled issues. Global optimal solutions are derived. Recursive optimization algorithms for distributed control strategies are introduced and shown to …


Learning Convolutional Neural Network For Face Verification, Elaheh Rashedi Jan 2018

Learning Convolutional Neural Network For Face Verification, Elaheh Rashedi

Wayne State University Dissertations

Convolutional neural networks (ConvNet) have improved the state of the art in many applications. Face recognition tasks, for example, have seen a significantly improved performance due to ConvNets. However, less attention has been given to video-based face recognition. Here, we make three contributions along these lines.

First, we proposed a ConvNet-based system for long-term face tracking from videos. Through taking advantage of pre-trained deep learning models on big data, we developed a novel system for accurate video face tracking in the unconstrained environments depicting various people and objects moving in and out of the frame. In the proposed system, we …


Detectability Of Fuzzy Discrete Event Systems, Ahmed Mekki Jan 2018

Detectability Of Fuzzy Discrete Event Systems, Ahmed Mekki

Wayne State University Dissertations

Dynamic systems that can be modeled in terms of discrete states and a synchronous events are known as discrete event systems (DES). A DES is defined in terms of states, events, transition dynamics, and initial state. Knowing the system’s state is crucial in many applications for certain actions (events) to be taken. A DES system is considered a fuzzy discrete event system (FDES) if its states and events are vague in nature; for such systems, the system can be in more than one state at the same time with different degrees of possibility (membership). In this research we introduce a …


On The Design Of Low-Complexity High-Speed Arithmetic Circuits In Quantum-Dot Cellular Automata Nanotechnology, Amjad Almatrood Jan 2017

On The Design Of Low-Complexity High-Speed Arithmetic Circuits In Quantum-Dot Cellular Automata Nanotechnology, Amjad Almatrood

Wayne State University Dissertations

For the last four decades, the implementation of very large-scale integrated systems has largely based on complementary metal-oxide semiconductor (CMOS) technology. However, this technology has reached its physical limitations. Emerging nanoscale technologies such as quantum-dot cellular automata (QCA), single electron tunneling (SET), and tunneling phase logic (TPL) are major candidate for possible replacements of CMOS. These nanotechnologies use majority and/or minority logic and inverters as circuit primitives. In this dissertation, a comprehensive methodology for majority/minority logic networks synthesis is developed. This method is capable of processing any arbitrary multi-output Boolean function to nd its equivalent optimal majority logic network targeting …


Actuation Of Droplets Using Transparent Graphene Electrodes For Tunable Lenses And Biomedical Applications, Ali Shahini Jan 2017

Actuation Of Droplets Using Transparent Graphene Electrodes For Tunable Lenses And Biomedical Applications, Ali Shahini

Wayne State University Dissertations

Variable focal length liquid microlenses are the next candidate for a wide variety of applications. Driving mechanism of the liquid lenses can be categorized into mechanical and electrical actuation. Among different actuation mechanisms, EWOD is the most common tool for actuation of the liquid lenses. In this dissertation, we have demonstrated versatile and low-cost miniature liquid lenses with graphene as electrodes. Tunable focal length is achieved by changing both curvature of the droplet using electrowetting on dielectric (EWOD) and applied pressure. Ionic liquid and KCl solution are utilized as lens liquid on the top of a flexible Teflon-coated PDMS/parylene membrane. …


Video Stream Adaptation In Computer Vision Systems, Yousef Sharrab Sharrab Jan 2017

Video Stream Adaptation In Computer Vision Systems, Yousef Sharrab Sharrab

Wayne State University Dissertations

Computer Vision (CV) has been deployed recently in a wide range of applications, including surveillance and automotive industries. According to a recent report, the market for CV technologies will grow to $33.3 billion by 2019. Surveillance and automotive industries share over 20% of this market. This dissertation considers the design of real-time CV systems with live video streaming, especially those over wireless and mobile networks. Such systems include video cameras/sensors and monitoring stations. The cameras should adapt their captured videos based on the events and/or available resources and time requirement. The monitoring station receives video streams from all cameras and …


Cascaded Converters For Integration And Management Of Grid Level Energy Storage Systems, Zuhair Muhammed Alaas Jan 2017

Cascaded Converters For Integration And Management Of Grid Level Energy Storage Systems, Zuhair Muhammed Alaas

Wayne State University Dissertations

ABSTRACT

CASCADED CONVERTERS FOR INTEGRATION AND MANAGEMENT OF GRID-LEVEL ENERGY STORAGE SYSTEMS

by

ZUHAIR ALAAS

December 2017

Advisor: Dr. Caisheng Wang

Major: ELECTRICAL ENGINEERING

Degree: Doctor of Philosophy

This research work proposes two cascaded multilevel inverter structures for BESS. The gating and switching control of switching devices in both inverter typologies are done by using a phase-shifted PWM scheme. The first proposed isolated multilevel inverter is made up of three-phase six-switch inverter blocks with a reduced number of power components compared with traditional isolated CHB. The suggested isolated converter has only one battery string for three-phase system that can be …


On Detectability Of Networked Discrete Event Systems, Yazeed Sasi Jan 2017

On Detectability Of Networked Discrete Event Systems, Yazeed Sasi

Wayne State University Dissertations

Detectability of discrete event systems, the ability to determine the current and subsequent states, is very important in supervisory control and many other applications. So far only detectability of non-networked discrete event systems has been defined and investigated. Non-networked discrete event systems assume all the communication to be carried out on time without any delays or losses. The assumption of reliable link is true when the distance of communication is short; however, it is often violated in networked systems. In my dissertation, I investigate the detectability for the networked discrete event systems. Because applications vary, we investigate the four types …


Development Of Carbon Based Neural Interface For Neural Stimulation/Recording And Neurotransmitter Detection, Wenwen Yi Jan 2016

Development Of Carbon Based Neural Interface For Neural Stimulation/Recording And Neurotransmitter Detection, Wenwen Yi

Wayne State University Dissertations

Electrical stimulation and recording of neural cells have been widely used in basic neuroscience studies, neural prostheses, and clinical therapies. Stable neural interfaces that effectively communicate with the nervous system via electrodes are of great significance. Recently, flexible neural interfaces that combine carbon nanotubes (CNTs) and soft polymer substrates have generated tremendous interests. CNT based microelectrode arrays (MEAs) have shown enhanced electrochemical properties compared to commonly used electrode materials such as tungsten, platinum or titanium nitride. On the other hand, the soft polymer substrate can overcome the mechanical mismatch between the traditional rigid electrodes (or silicon shank) and the soft …


Local Field Enhancement On Demand Based On Hybrid Plasmonic Dielectric Directional Coupler, Kholod Adhem Adhem Jan 2016

Local Field Enhancement On Demand Based On Hybrid Plasmonic Dielectric Directional Coupler, Kholod Adhem Adhem

Wayne State University Dissertations

The concept of local field enhancement using conductor- gap-dielectric-substrate (CGDS) waveguide structure is proposed. The dispersion equation is derived analytically and solved numerically. The solution of the dispersion equation reveals the anti-crossing behavior of coupled modes. The optimal gap layer thickness and the coupling length of the guided modes are obtained. The mechanism of the CGDS works as follows: Light waves are guided by conventional low-loss dielectric waveguides and, upon demand, they are transformed into highly confined plasmonic modes with strong local field enhancement, and get transformed back into low-loss dielectric modes. As an example, in a representative CGDS structure, …


Torque Accuracy Improvement Via Explicit Torque Feedback Control For Internal Combustion Spark Ignition Engines, Anwar Alkeilani Jan 2016

Torque Accuracy Improvement Via Explicit Torque Feedback Control For Internal Combustion Spark Ignition Engines, Anwar Alkeilani

Wayne State University Dissertations

At the present time, both control and estimation accuracies of engine torque are causes for under-achieving optimal drivability and performance in today’s production vehicles. The major focus in this area has been to enhance torque estimation and control accuracies using existing open-loop torque control and estimation structures. Such an approach does not guarantee optimum torque tracking accuracy and optimum estimation accuracy due to air flow and efficiencies estimations errors. Furthermore, current approach overlooks the fast torque path tracking which does not have any related feedback. Recently, explicit torque feedback control has been proposed in the literature using either estimated or …


Two-Dimensional Low-Resistance Contacts For High Performance Wse2 And Mos2 Transistors, Hsun Jen Chuang Jan 2016

Two-Dimensional Low-Resistance Contacts For High Performance Wse2 And Mos2 Transistors, Hsun Jen Chuang

Wayne State University Dissertations

ABSTRACT

TWO-DIMENSIONAL LOW-RESISTANCE CONTACTS FOR HIGH PERFORMANCE WSe2 and MoS2, TRANSISTORS

by

Hsun-jen Chuang

May 2016

Advisor: Dr. Zhixian Zhou

Major: Physics

Degree: Doctor of Philosophy

Two-dimensional layered materials beyond graphene such as transition metal dichalcogenides (TMDs) have attracted a lot of interests due to their superior property in many aspects. In this work, I am focusing on two TMD materials: WSe2 and MoS2. The main objective this work is to develop novel approaches to fabricating low-resistance ohmic contacts to TMDs for low power, high performance electronic applications. First, we used graphene as electrical contacts for WSe2 field-effect transistor with …


Dense Periodical Patterns In Photonic Devices: Technology For Fabrication And Device Performance, Sabarish Chandramohan Jan 2016

Dense Periodical Patterns In Photonic Devices: Technology For Fabrication And Device Performance, Sabarish Chandramohan

Wayne State University Dissertations

For the fabrication, focused ion beam parameters are investigated to successfully fabricate dense periodical patterns, such as gratings, on hard transition metal nitride such as zirconium nitride. Transition metal nitrides such as titanium nitride and zirconium nitride have recently been studied as alternative materials for plasmonic devices because of its plasmonic resonance in the visible and near-infrared ranges, material strength, CMOS compatibility and optical properties resembling gold. Coupling of light on the surface of these materials using sub-micrometer gratings gives additional capabilities for wider applications. Here we report the fabrication of gratings on the surface of zirconium nitride using gallium …


Building Computing-As-A-Service Mobile Cloud System, Kun Wang Jan 2015

Building Computing-As-A-Service Mobile Cloud System, Kun Wang

Wayne State University Dissertations

The last five years have witnessed the proliferation of smart mobile devices, the explosion of various mobile applications and the rapid adoption of cloud computing in business, governmental and educational IT deployment. There is also a growing trends of combining mobile computing and cloud computing as a new popular computing paradigm nowadays. This thesis envisions the future of mobile computing which is primarily affected by following three trends: First, servers in cloud equipped with high speed multi-core technology have been the main stream today. Meanwhile, ARM processor powered servers is growingly became popular recently and the virtualization on ARM systems …


A Comprehensive Study Of Nonlinear Effects Of Coupling Materials In Ultrasound Infrared Imaging, Yuyang Song Jan 2014

A Comprehensive Study Of Nonlinear Effects Of Coupling Materials In Ultrasound Infrared Imaging, Yuyang Song

Wayne State University Dissertations

Nondestructive Evaluation (NDE) is a multidisciplinary field of research, which is focused on the development of analysis and measurement technologies for the quantitative characterization of materials, components and structures. It is a key process used in product evaluation, troubleshooting for the quality assurance in industry. Sonic Infrared (IR) Imaging technology is a hybrid sensing and imaging technique, in which cracks in an object are caused to become visible in the infrared imaging through frictional heating associated with the application of a short pulse of low-frequency ultrasound. The technique uses pulses of ultrasonic excitation applied to a sample for a fraction …


Analysis Of A Dual Scissored-Pair,Variable-Speed, Control Moment Gyroscope Driven Spherical Robot, Richard Chase Jan 2014

Analysis Of A Dual Scissored-Pair,Variable-Speed, Control Moment Gyroscope Driven Spherical Robot, Richard Chase

Wayne State University Dissertations

The objective of this research is to compare barycenter offset based designs of spherical robots to control moment gyroscope (CMG) based designs in order to determine which approach is most effective. The first objective was to develop a list of current state of the art designs in order to gain an overall understanding of what the obstacles in this area of research were. The investigation showed that barycenter offset designs can produce a low, continuous output torque, whereas CMG based designs can usually only produce a high, momentary output torque. The second objective was to develop a CMG based design …