Electrical and Computer Engineering Commons^™

Microwave Material Characterization Of Alkali-Silica Reaction (Asr) Gel In Cementitious Materials, Ashkan Hashemi

Doctoral Dissertations

"Since alkali-silica reaction (ASR) was recognized as a durability challenge in cement-based materials over 70 years ago, numerous methods have been utilized to prevent, detect, and mitigate this issue. However, quantifying the amount of produced ASR byproducts (i.e., ASR gel) in-service is still of great interest in the infrastructure industry. The overarching objective of this dissertation is to bring a new understanding to the fundamentals of ASR formation from a microwave dielectric property characterization point-of-view, and more importantly, to investigate the potential for devising a microwave nondestructive testing approach for ASR gel detection and evaluation. To this end, a comprehensive …

Adaptive Filters For Sparse System Identification, Jianming Liu

Doctoral Dissertations

"Sparse system identification has attracted much attention in the field of adaptive algorithms, and the adaptive filters for sparse system identification are studied. Firstly, a new family of proportionate normalized least mean square (PNLMS) adaptive algorithms that improve the performance of identifying block-sparse systems is proposed. The main proposed algorithm, called block-sparse PNLMS (BS-PNLMS), is based on the optimization of a mixed ℓ_2,1 norm of the adaptive filter's coefficients. A block-sparse improved PNLMS (BS-IPNLMS) is also derived for both sparse and dispersive impulse responses. Meanwhile, the proposed block-sparse proportionate idea has been extended to both the proportionate affine projection …

Boundary Control Of Parabolic Pde Using Adaptive Dynamic Programming, Behzad Talaei

Doctoral Dissertations

"In this dissertation, novel adaptive/approximate dynamic programming (ADP) based state and output feedback control methods are presented for distributed parameter systems (DPS) which are expressed as uncertain parabolic partial differential equations (PDEs) in one and two dimensional domains. In the first step, the output feedback control design using an early lumping method is introduced after model reduction. Subsequently controllers were developed in four stages; Unlike current approaches in the literature, state and output feedback approaches were designed without utilizing model reduction for uncertain linear, coupled nonlinear and two-dimensional parabolic PDEs, respectively. In all of these techniques, the infinite horizon cost …

Model Based Fault Diagnosis And Prognosis Of Class Of Linear And Nonlinear Distributed Parameter Systems Modeled By Partial Differential Equations, Jia Cai

Doctoral Dissertations

"With the rapid development of modern control systems, a significant number of industrial systems may suffer from component failures. An accurate yet faster fault prognosis and resilience can improve system availability and reduce unscheduled downtime. Therefore, in this dissertation, model-based prognosis and resilience control schemes have been developed for online prediction and accommodation of faults for distributed parameter systems (DPS). First, a novel fault detection, estimation and prediction framework is introduced utilizing a novel observer for a class of linear DPS with bounded disturbance by modeling the DPS as a set of partial differential equations.

To relax the state measurability …

Low-Complexity Iterative Receiver Algorithms For Multiple-Input Multiple-Output Underwater Wireless Communications, Weimin Duan

Doctoral Dissertations

"This dissertation proposes three low-complexity iterative receiver algorithms for multiple-input multiple-output (MIMO) underwater acoustic (UWA) communications. First is a bidirectional soft-decision feedback Turbo equalizer (Bi-SDFE) which harvests the time-reverse diversity in severe multipath MIMO channels. The Bi-SDFE outperforms the original soft-decision feedback Turbo equalizer (SDFE) while keeping its total computational complexity similar to that of the SDFE. Second, this dissertation proposes an efficient direct adaptation Turbo equalizer for MIMO UWA communications. Benefiting from the usage of soft-decision reference symbols for parameter adaptation as well as the iterative processing inside the adaptive equalizer, the proposed algorithm is efficient in four aspects: …

A Control Theoretic Approach For Security Of Cyber-Physical Systems, Haifeng Niu

Doctoral Dissertations

"In this dissertation, several novel defense methodologies for cyber-physical systems have been proposed. First, a special type of cyber-physical system, the RFID system, is considered for which a lightweight mutual authentication and ownership management protocol is proposed in order to protect the data confidentiality and integrity. Then considering the fact that the protection of the data confidentiality and integrity is insufficient to guarantee the security in cyber-physical systems, we turn to the development of a general framework for developing security schemes for cyber-physical systems wherein the cyber system states affect the physical system and vice versa. After that, we apply …

High-Voltage-Gain Dc-Dc Power Electronic Converters -- New Topologies And Classification, Bhanu Prashant Reddy Baddipadiga

Doctoral Dissertations

"This dissertation proposes two new high-voltage-gain dc-dc converters for integration of renewable energy sources in 380/400V dc distribution systems. The first high-voltage-gain converter is based on a modified Dickson charge pump voltage multiplier circuit. The second high-voltage-gain converter is based on a non-inverting diode-capacitor voltage multiplier cell. Both the proposed converters offer continuous input current and low voltage stress on switches which make them appealing for applications like integration of renewable energy sources. The proposed converters are capable for drawing power from a single source or two sources while having continuous input current in both cases. Theoretical analysis of the …

Characterization Of An Integrated Circuit With Respect To Electrostatic Discharge-Induced Soft Failures, Benjamin J. Orr

Doctoral Dissertations

"This research proposal presents a methodology whereby an integrated circuit (IC) can be characterized with respect to soft-failures induced by Electrostatic Discharge (ESD)-like events. This methodology uses an exclusively "black-box" approach to determine the response of an IC in a system-level environment, thereby allowing it to be implemented without intimate knowledge of the DUT IC. Results from this methodology can be referenced during system design to raise awareness of specific vulnerabilities of the core system ICs.

During work on this methodology, several sub topics have been explored and developed in the field of system-level ESD. Sections 2 and 3 introduce …

Efficient And Quantitative Emc Predictions (Emission And Immunity) For Ecu Modules, Guangyao Shen

Doctoral Dissertations

"This dissertation consists of three papers. In the first paper, a methodology of building an IC model capable of predicting failures for given disturbances at the clock input based on limited or no knowledge about IC internals was developed.

In the second paper, the maximized radiated emissions of the heat-sink/IC structure are predicted up to 40 GHz by creating an equivalent source using the measured electrical field in the gap between the heat-sink and ICs. The electric field is detected by an E-field probe made of an open coaxial cable coated with absorbing material. A numerical model is built in …

Experimental Performance Evaluation And Design Of Schemes For Passive Rfid Network, Shadi Ebrahimi-Asl

Doctoral Dissertations

"Passive Radio Frequency Identification (RFID) is a short range technology for transferring information. The main advantage of passive RFID systems over active communication systems is the battery-less operation at the client sides. However, there are two major challenges that limit the widespread adaptation of passive RFID systems: short communication range and low read rate in dense deployments. This dissertation addresses these issues by studying the root causes and develops solutions for them.

In this dissertation, understanding the backscattering behavior of antennas and also the mutual coupling interactions among them are found to be the root causes of the two above-mentioned …

Adaptive Consensus Based Formation Control Of Unmanned Vehicles, Haci Mehmet Guzey

Doctoral Dissertations

"Over the past decade, the control research community has given significant attention to formation control of multiple unmanned vehicles due to a variety of commercial and defense applications. Consensus-based formation control is considered to be more robust and reliable when compared to other formation control methods due to scalability and inherent properties that enable the formation to continue even if one of the vehicles experiences a failure. In contrast to existing methods on formation control where the dynamics of the vehicles are neglected, this dissertation in the form of four papers presents consensus-based formation control of unmanned vehicles-both ground and …

Diamond Mems Biosensors: Development And Applications, Wenli Zhang

Doctoral Dissertations

This research focuses on the development a dielectrophoresis-enhanced microfluidic impedance biosensor (DEP-e-MIB) to enable fast response, real-time, label-free, and highly sensitive sensor for bacterial detection in clinical sample. The proposed design consists of application of dielectrophoresis (DEP) across a microfluidic channel to one of the impedance spectroscopy electrodes in order to improve the existent bacterial detection limits with impedance spectroscopy. In order to realize such a design, choice of electrode material with a wide electrochemical potential window for water is very important. Conventional electrode material, such as gold, are typically insulated for the application of DEP, and they fail when …

Intrusion Detection System Of Industrial Control Networks Using Network Telemetry, Stanislav Ponomarev

Doctoral Dissertations

Industrial Control Systems (ICSs) are designed, implemented, and deployed in most major spheres of production, business, and entertainment. ICSs are commonly split into two subsystems - Programmable Logic Controllers (PLCs) and Supervisory Control And Data Acquisition (SCADA) systems - to achieve high safety, allow engineers to observe states of an ICS, and perform various configuration updates. Before wide adoption of the Internet, ICSs used "air-gap" security measures, where the ICS network was isolated from other networks, including the Internet, by a physical disconnect [1]. This level of security allowed ICS protocol designers to concentrate on the availability and safety of …

Models Predicting The Performance Of Ic Component Or Pcb Channel During Electromagnetic Interference, Chunchun Sui

Doctoral Dissertations

"This dissertation is composed of three papers, which cover the prediction of the characteristics of jitter due to crosstalk and due to simultaneous switching noise, and covers susceptibility of delay locked loop (DLL) to electromagnetic interference.

In the first paper, an improved tail-fit de-convolution method is proposed for characterizing the impact of deterministic jitter in the presence of random jitter. A Wiener filter de-convolution method is also presented for extracting the characteristics of crosstalk induced jitter from measurements of total jitter made when the crosstalk sources were and were not present. The proposed techniques are shown to work well both …

Stability Design Criteria And Volt Var Control For Distribution System With Single Phase Solid State Transformers, Darshit Girishchandra Shah

Doctoral Dissertations

Due to recent advancements in semiconductor technology, power electronic converters for high voltage, high power, and high frequency applications will soon be commercially available. Conventional single phase distribution transformers are replaced by solid state transformers (SST) in a distribution test system to investigate their interactive dynamics. Under certain circumstances, instabilities due to harmonic resonance are observed. A design criterion for solid state transformer during no load conditions has been proposed in order to avoid instability using an impedance-based analysis. Stability assessment is also extended to include the impact of distribution system voltages and system wide impedance analysis. It is shown …

Application Of Unified Invariants For Cyber Physical Systems In Smart Grids, Tamal Paul

Doctoral Dissertations

Cyber-Physical Systems (CPS) are complex engineered systems which consist of physical components with an underlying cyber network. The three main components of a cyber-physical System are: physical system, networking and communications element and a distributed cyber system. The primary challenge for cyber-physical systems is to understand what happens when various sub-systems, which have been developed in an isolated environment, are integrated. CPS studies need to ensure sub-systems that had been designed in isolation to meet certain specifications, when combined, do not cause the overall system to fail. The crux of cyber-physical research is thus to find a common platform to …

Detection And Recognition Of R/F Devices Based On Their Unintended Electromagnetic Emissions Using Stochastic And Computational Intelligence Methods, Shikhar Prasad Acharya

Doctoral Dissertations

"Radio Frequency (RF) devices produce some amount of Unintended Electromagnetic Emissions (UEEs). UEEs are generally unique to a device and can be thought of as a signature of the device. This property of uniqueness of UEEs can be used to detect and identify the device producing the emission. The problem with UEEs is that they are very low in power and are often buried deep inside the noise band which makes them difficult to detect. There are two types of UEE detection methods. The first one is called stimulated detection method where the UEEs of a device are enhanced using …

Electromagnetic Compatibility In Power Inverter Design, Natalia Bondarenko

Doctoral Dissertations

"Power inverter systems generate significant electromagnetic emissions. Methods were studied to model these systems and to reduce their emissions. Three topics are presented in this dissertation.

Methods were developed to obtain simple SPICE models for complex systems which relate circuit components to physical geometry within the system. These models were derived using measurements or using partial element equivalent circuit (PEEC) and model size reduction techniques developed in this dissertation. Methods were proposed for developing a measurement-based model and were applied to a real power inverter/motor system. The model was used to identify system geometries responsible for critical resonances and to …

Printed Circuit Board Power Distribution Network Modeling, Analysis And Design, And, Statistical Crosstalk Analysis For High Speed Digital Links, Ketan Shringarpure

Doctoral Dissertations

"High-speed digital systems are moving to higher data rates and smaller supply voltages as the scale of integration goes smaller. With the smaller bit periods and the smaller operating voltages, the tolerable timing and noise margins are reducing. There are many sources of disturbances contributing to the tolerance margins. These margins have to account for inter symbol interference (ISI), reflections, jitter, noise from power distribution networks (PDN) and crosstalk. An important task during the design phase of the system is to find and mitigate the noise from such sources. This thesis proposes modeling and analysis methodology to resolve some of …

Advanced Control Of Grid-Connected Multilevel Power Electronic Rectifiers, Sangin Lee

Doctoral Dissertations

"Multilevel power electronic converters have been gaining attention due to their ability to supply high amounts of power and to handle high voltage levels. In this dissertation, grid connected AC-DC rectifier application is investigated with different topologies and control scheme.

At first, neutral point clamped (NPC) rectifier is employed to transfer power from the grid to the load. The NPC rectifier has two capacitors in order to build multilevel output voltage. However, it causes voltage unbalancing problem. Therefore, the new method has been proposed to regulate each capacitor voltage at the same voltage level. Experimental results show that it is …

The Radiation Physics, Mitigation Approaches And Design Guidelines Of High-Speed Connectors And Cables Analyzed With Numerical Modeling, Analytical Formulation And Measurements, Jing Li

Doctoral Dissertations

The dissertation is composed of three papers, which cover the radiation and mitigation of high-speed connectors and cables analyzed with full wave simulation, numerical modeling, analytical formulation and measurements.

In the first paper, the radiation from the optical cage connector in the frequency range of 4-28 GHz is analyzed with validated full-wave simulation model and analytical formulas. The radiation from the optical cage connector is suppressed with absorbing materials, and the coupling path in optical link is verified, together with the optical cage and module enclosure.

In the second paper, radiation from antenna-mode current and TL-mode current is briefly reviewed …

Modelling Of Interconnects In 3dic Based On Layered Green Functions, Siming Pan

Doctoral Dissertations

As traditional CMOS scaling pace gradually slows down, three-dimensional (3D) integration offers another dimension of in the ”More-than-Moore” era. In this dissertation, a number of investigations were conducted to better model interconnects in 3D integrated circuit (IC), to evaluate electrical behavior including delay, power consumption, signal integrity (SI), and power integrity (PI) for 3D ICs. Partial Element Equivalent Circuit (PEEC) method with layered Green’s function is studied here, since it consumes less computational resources and provides better physical insight to model the interconnects in 3DIC for high-speed digital circuits. The work is organized as a series of papers. The first …

Small Signal Modeling And Analysis Of Microgrid Systems, Md. Rasheduzzaman

Doctoral Dissertations

This dissertation focuses on small-signal modeling and analysis of inverter based microgrid systems. The proposed microgrid consists of two microsources placed on two different buses. The buses are connected using a distribution feeder with some impedance. The proposed microgrid can operate with the grid support, or without the grid support. When operated without the grid support, the standalone system’s microsources participate in controlling the system voltage and frequency. For a non-inertia source, such as the inverter, the load perturbations play an important role in system dynamics. In paper-I, such complex system was studied.

In the grid-tied mode, the microsources share …

Pulsed Inductive Plasma Studies By Spectroscopy And Internal Probe Methods, Warner C. Meeks

Doctoral Dissertations

The broad effort of the Missouri Plasmoid Experiment is to elucidate the energy conversion processes in a pulsed inductive discharge due to the presence of plasma. The test article is a 440 to 490 kHz theta-pinch (or solenoidal) geometry coil with a stored energy of around 80 joules. In this work experimental hydrogen, helium, argon and xenon data at back-fill pressures of 10 to 100 mTorr (1.3 to 133.3 Pa) are obtained and interpreted. Spectral and internal probe studies were performed on MPX Mk.I and Mk.II devices, respectively. IR spectra were acquired in the Mk.I device for argon and xenon. …

Quantification Of Information Flow In Cyber Physical Systems, Li Feng

Doctoral Dissertations

"In Cyber Physical Systems (CPSs), traditional security mechanisms such as cryptography and access control are not enough to ensure the security of the system since complex interactions between the cyber portion and physical portion happen frequently. In particular, the physical infrastructure is inherently observable; aggregated physical observations can lead to unintended cyber information leakage. Information flow analysis, which aims to control the way information flows among different entities, is better suited for CPSs than the access control security mechanism. However, quantifying information leakage in CPSs can be challenging due to the flow of implicit information between the cyber portion, the …

Computational Approaches For Voltage Stability Monitoring And Control In Power Systems, Kangombe Joseph Makasa

Doctoral Dissertations

"The electric power grid is a complex, non-linear, non-stationary system comprising of thousands of components such as generators, transformers, transmission lines and advanced power electronics based control devices, and customer loads. The complexity of the grid has been further increased by the introduction of smart grid technologies. Smart grid technology adds to the traditional power grids advanced methods of communication, computation and control as well as increased use of renewable energy sources such as wind and solar farms and a higher penetration of plug-in electric vehicles among others. The smart grid has resulted in much more distributed generation, bi-directional powerflows …

Near-Field Scanning Study For Radio Frequency Interference Estimation, Jingnan Pan

Doctoral Dissertations

"This dissertation discusses the novel techniques using near-fields scanning to do radio frequency interference (RFI) estimation. As the electronic products are becoming more and more complicated, the radio frequency (RF) receiver in the system is very likely interfered by multiple noise sources simultaneously. A method is proposed to identify the interference from different noise sources separately, even when they are radiating at the same time. This method is very helpful for engineers to identify the contribution of the coupling from different sources and further solve the electromagnetic interference issues efficiently. On the other hand, the equivalent dipole-moment models and a …

Distributed State Verification In The Smart Grid Using Physical Attestation, Thomas Patrick Roth

Doctoral Dissertations

"A cyber process in a distributed system can fabricate its internal state in its communications with its peers. These state fabrications can cause other processes in the distributed system to make incorrect control decisions. Cyber-physical systems have a unique advantage in the detection of falsified states because processes typically have observable effects on a shared physical infrastructure. This physical infrastructure acts as a high-integrity message channel that broadcasts changes in individual process states. The objective of this research is to demonstrate that there are cases where physical feedback from the shared infrastructure can be used to detect state fabrications. To …

Detection, Identification And Localization Of R/C Electronic Devices Through Their Unintended Emissions, Vivek Thotla

Doctoral Dissertations

"The accurate and reliable detection of unintended emissions from radio receivers has a broad range of commercial and security applications. This thesis presents detection, identification, and localization methods for multiple RC electronic devices in a realistic environment. First, a Hurst parameter based detection method for super-regenerative receivers (SRR) has been used for detection. Hurst parameter based detection method exploits a self-similarity property of the SRR receiver emissions to distinguish it from background noise. Second paper presents a novel detection and localization scheme of multiple RC electronic devices called Edge-Synthetic Aperture Radar (Edge-SAR). It employs cost-effective, mobile antenna-array detectors. Two types …

Event Sampled Optimal Adaptive Regulation Of Linear And A Class Of Nonlinear Systems, Avimanyu Sahoo

Doctoral Dissertations

In networked control systems (NCS), wherein a communication network is used to close the feedback loop, the transmission of feedback signals and execution of the controller is currently carried out at periodic sampling instants. Thus, this scheme requires a significant computational power and network bandwidth. In contrast, the event-based aperiodic sampling and control, which is introduced recently, appears to relieve the computational burden and high network resource utilization. Therefore, in this dissertation, a suite of novel event sampled adaptive regulation schemes in both discrete and continuous time domain for uncertain linear and nonlinear systems are designed.

Event sampled Q-learning and …