Electrical and Computer Engineering Commons^™

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 …

Hybrid Electronic Materials: Characterization And Thin-Film Deposition, Kalyan Chakravarthy Kanakamedala

LSU Doctoral Dissertations

Hybrid Electronic Materials (HEMs), as defined for this dissertation, are combinations of organic and inorganic materials as may be used to fabricate active device components in “beyond the transistor” electronics. However, the use of organics is often limited by issues such as thermal stability, compatibility with traditional (semiconductor) materials, and current processing technology. Thus, we began our exploration of HEMs with a “new” class of materials called GUMBOS (Group of Uniform Materials Based on Organic Salts) as derived from ionic liquids. For this first segment of our work, we investigated selected species of GUMBOS and nanoGUMBOS via their current-voltage characteristics, …

3d Persistence Of Vision Display, Austin Jensen, Mark Elliott, Michael Reimer

Electrical and Computer Engineering

By rapidly sweeping a varying 2D image, a 3D image appears to the human eye. We have developed a 3D Persistence of Vision Display by rotating a 2D grid of LED’s. Our display has multiple operating modes and could be expanded to many other applications.

Acoustic Room Mapping Utilizing Blind Source Separation, Michael L. Schena

Electrical and Computer Engineering

• Acoustic signals used to map the walls of a room
• Blind Source Separation (BSS) technique used instead of traditional “pinging” techniques
• Locations of signal sources are not necessary
• Possibility to transmit data while locating signal sources

All Grades Technology (Agt) Laser Receiver, Tyler Wilson

Electrical and Computer Engineering

The AGT Laser Receiver is a landscaping tool used to measure the elevation offset from a given location (benchmark). The tool is used to set grade on a job site.

The AGT Laser Receiver consists of two main components, the AGT Remote and AGT Tool. The AGT Tool captures the laser beam and processes the information. The AGT Remote receives the processed data and displays the offset to the screen.

Modular Timing Constraints For Delay-Insensitive Systems, Hoon Park, Anping He, Marly Roncken, Xiaoyu Song, Ivan Sutherland

Electrical and Computer Engineering Faculty Publications and Presentations

This paper introduces ARCtimer, a framework for modeling, generating, verifying, and enforcing timing constraints for individual self-timed handshake components. The constraints guarantee that the component’s gate-level circuit implementation obeys the component’s handshake protocol specification. Because the handshake protocols are delayinsensitive, self-timed systems built using ARCtimer-verified components are also delay-insensitive. By carefully considering time locally, we can ignore time globally. ARCtimer comes early in the design process as part of building a library of verified components for later system use. The library also stores static timing analysis (STA) code to validate and enforce the component’s constraints in any self-timed system built …

Coupled-Oscillator Associative Memory Array Operation For Pattern Recognition, Dmitri E. Nikonov, Gyorgy Csaba, Wolfgang Porod, Tadashi Shibata, Danny Voils, Dan Hammerstrom, Ian A. Young, George I. Bourianoff

Electrical and Computer Engineering Faculty Publications and Presentations

Operation of the array of coupled oscillators underlying the associative memory function is demonstrated for various interconnection schemes (cross-connect, star phase keying and star frequency keying) and various physical implementation of oscillators (van der Pol, phase-locked loop, spin torque). The speed of synchronization of oscillators and the evolution of the degree of matching is studied as a function of device parameters. The dependence of errors in association on the number of the memorized patterns and the distance between the test and the memorized pattern is determined for Palm, Furber and Hopfield association algorithms.

Wavelet-Coupled Machine Learning Methods For Drought Forecast Utilizing Hybrid Meteorological And Remotely-Sensed Data, R. Tan, Marek Perkowski

Electrical and Computer Engineering Faculty Publications and Presentations

In this study, a statistical drought early warning method is proposed using novel machine learning algorithms, with the inclusion of multiple drought-related attributes from precipitation, satellite-derived land cover vegetation indices, and surface discharge. The forecast is made for the long-term hydrological drought in the region of Central Valley, California. The wavelet transform analysis is employed in combination with support vector regression and artificial neural network algorithms for improving the drought prediction effectiveness. The performance of the drought prediction is evaluated using three statistical metrics: Coefficient of Determination (R2 ), Root-Mean-Square Error (RMSE), and Mean-Absolute-Error (MAE). The results clearly indicate that …

Influence Of Resonant And Non-Resonant Vibrational Excitation Of Ammonia Molecules In Gallium Nitride Synthesis, Hossein Rabiee Golgir, Yunshen Zhou, Kamran Keramatnejad, Yongfeng Lu

Department of Electrical and Computer Engineering: Dissertations, Theses, and Student Research

Attempts on the selective promotion of gallium nitride (GaN) growth were investigated by deploying laserassisted vibrational excitation of reactant molecules, which deposits energy selectively into specific molecules and activate the molecules towards the selected reaction pathways. Laser-assisted metal organic chemical vapor deposition (LMOCVD) of GaN was studied using a wavelength-tunable CO2 laser. The NH-wagging modes (υ2) of ammonia (NH3) precursor molecules are strongly infrared active and perfectly match the emission line of the CO2 laser at 9.219, 10.350, and 10.719 μm. On- and off-resonance excitations of molecules were performed via tuning the incident laser wavelengths at on-resonant wavelength 9.219 μm …

Defect Characterization Of 4h-Sic By Deep Level Transient Spectroscopy (Dlts) And Influence Of Defects On Device Performance, Mohammad Abdul Mannan

Theses and Dissertations

Silicon carbide (SiC) is one of the key materials for high power opto-electronic devices due to its superior material properties over conventional semiconductors (e.g., Si, Ge, GaAs, etc). SiC is also very stable and a highly suitable material for radiation detection at room temperature and above. The availability of detector grade single crystalline bulk SiC is limited by the existing crystal growth techniques which introduce extended and microscopic crystallographic defects during the growth process. Recently, SiC based high-resolution semiconductor detectors for ionizing radiation have attracted world-wide attention due to the availability of high resistive, highly crystalline epitaxial layers with very …

An Investigation Into Quasi-Tunable Rf Passive Circuit Design, Terry L. Moss

Theses and Dissertations

Modern wireless electronic circuit design is continually challenged by the needs to reduce circuit size, and to also function reliably with lower power levels. To that end, two aspects of RFIC circuit design and technology have gained great interest, i.e. RF MEMS switching technology, and RF MEMS passive component development. MEMS (Micro-Electromechanical Systems) technology, originally developed for the defense industry, has been in development since the 1970s, and today enjoys wide range of utilization, from the defense industry to the automotive industry. Spiral inductors used in RFIC circuits, e.g. silicon technology, are ubiquitous in wireless RFIC applications. The tradeoff with …

Fabrication And Characterization Of Graphene Based Biocompatible Ion-Sensitive Field Effect Transistor (Isfet), Rina Patel

Theses and Dissertations

Graphene, a two-dimensional material with a high surface to volume ratio, has drawn extensive research enthusiasm for applications in the field of electronic sensors. The special material properties that make graphene a highly promising material include its biocompatibility, very high mobility, low 1/f and thermal noise, modulation of carrier concentration and fermi level by electrical, optical, and chemical means. To exploit these properties for practical applications a large area high quality graphene, transferred on appropriate substrates, is required. In this work, high quality single monolayer graphene (determined from Raman spectroscopy) has been synthesized by chemical vapor deposition (CVD) technique for …

Technology Development And Characterization Of Aiinn/Gan Hemts For High Power Application, Mahbuba Sultana

Theses and Dissertations

AlInN has attracted much attention only recently as a material due to its unique and superior material properties, which is however known to be difficult to be grown among the III-nitride ternary compounds. The electrons confined at the heterointerface of coherently grown AlInN on GaN buffer layers determine crucial electronic properties. This dissertation has been designed targeting the lattice matched AlInN/GaN investigation with very detail to optimize the design, fabrication process, and electronic properties to realize AlInN/GaN HEMTs. Each single step of this process was optimized in order to improve device performance.

The work started with establishing the main features …

Dual-Band Non-Stationary Channel Modeling For The Air-Ground Channel, Ruoyu Sun

Theses and Dissertations

Multiple air-to-ground (AG) radio propagation channels are experimentally characterized for two frequency bands, C-band and L-band. These characterizations are aimed to support the specification of the control and non-payload communication (CNPC) links being designed for civil unmanned aircraft systems (UAS). The use of UAS is expected to grow dramatically in the coming decades. In the United States, UAS will be monitored and guided in their operation within the national airspace system (NAS) via the CNPC link. The specifications of the CNPC link are being designed by government, industries, academia and standards bodies such as the Radio Technical Commission for Aeronautics …

Application And Histology-Driven Refinement Of Active Contour Models To Functional Region And Nerve Delineation: Towards A Digital Brainstem Atlas, Nimal Patel, Sharmin Sultana, Tanweer Rashid, Dean Krusienski, Michel A. Audette

Electrical & Computer Engineering Faculty Publications

This paper presents a methodology for the digital formatting of a printed atlas of the brainstem and the delineation of cranial nerves from this digital atlas. It also describes on-going work on the 3D resampling and refinement of the 2D functional regions and nerve contours. In MRI-based anatomical modeling for neurosurgery planning and simulation, the complexity of the functional anatomy entails a digital atlas approach, rather than less descriptive voxel or surface-based approaches. However, there is an insufficiency of descriptive digital atlases, in particular of the brainstem. Our approach proceeds from a series of numbered, contour-based sketches coinciding with slices …

Iii-V Nitride Based Microcantilever Heaters For Unique Multimodal Detection Of Volatile Organic Compounds At Low Temperature, Ifat Jahangir

Theses and Dissertations

Detection of volatile organic compounds (VOCs), which are widely used in industrial processes and household products, is very important due to significant health hazards associated with them. VOCs are commonly detected using photo-ionization detectors (PIDs), suspended hot bead pellistors, or heated metal oxide semiconductor functionalization layers. However, these techniques used for detecting VOCs often suffer from one or more of the following issues - high power consumption, limited selectivity, complicated functionalization technique and expensive characterization tools. On the other hand, microcantilevers offer excellent avenues for molecular sensing that arises out of their high sensitivity to various physical parameter changes induced …

Rf Mems Resonators For Mass Sensing Applications, Ivan Fernando Rivera

USF Tampa Graduate Theses and Dissertations

Sensing devices developed upon resonant microelectromechanical and nanoelectromechanical (M/NEMS) system technology have become one of the most attractive areas of research over the past decade. These devices make exceptional sensing platforms because of their miniscule dimensions and resonant modes of operation, which are found to be extremely sensitive to added mass. Along their unique sensing attributes, they also offer foundry compatible microfabrication processes, low DC power consumption, and CMOS integration compatibility. In this work, electrostatically and piezoelectrically actuated RF MEMS bulk resonators have been investigated for mass sensing applications. The capacitively-transduced resonators employed electrostatic actuation to achieve desired resonance mode …

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 …

Localization And Tracking Of Electronic Devices With Their Unintended Emissions, Nurbanu Guzey

Doctoral Dissertations

"The precise localization and tracking of electronic devices via their unintended emissions has a broad range of commercial and security applications. Active stimulation of the receivers of such devices with a known signal generates very low power unintended emissions. This dissertation presents localization and tracking of multiple devices using both simulation and experimental data in the form of five papers.

First the localization of multiple emitting devices through active stimulation under multipath fading with a Smooth MUSIC based scheme in the near field region is presented. Spatial smoothing helps to separate the correlated sources and the multipath fading and results …

Tunable Absorption Based On Plasmonic Nanostructures Loaded With Graphene, Christos Argyropoulos

Department of Electrical and Computer Engineering: Faculty Publications

We present simulations of a hybrid graphene-plasmonic device constituted by periodic metallic nanowires placed over a dielectric spacer layer and a metallic film. The spacer layer is composed of a thin silica layer combined with an one-atom-thick graphene sheet. An electrically controlled ultra-compact absorption modulator can be realized based on the proposed theoretical device.