Electrical and Electronics Commons^™

Unified Large And Small Signal Discrete-Space Modeling For Pwm Converters In Ccm, Ehab Hamed Shoubaki

Electronic Theses and Dissertations

In this Thesis a Unified Discrete State-Space Model for power converters in CCM is presented. Two main approaches to arriving at the discrete model are used. The first approach involves an impulse function approximation of the duty cycle modulations of the converter switches , and this approach results in a small signal discrete model. The Second approach is direct and does not involve any approximation of the modulations , this approach yields both a large signal nonlinear discrete model and a linear small signal model. Harmonic analysis of the converter states at steady-state is done for steady-state waveform acquisition , …

Background Stabilization And Motion Detection In Launch Pad Video Monitoring, Kaushik Gopalan

Electronic Theses and Dissertations

Automatic detection of moving objects in video sequences is a widely researched topic with application in surveillance operations. Methods based on background cancellation by frame differencing are extremely common. However this process becomes much more complicated when the background is not completely stable due to camera motion. This thesis considers a space application where surveillance cameras around a shuttle launch site are used to detect any debris from the shuttle. The ground shake due to the impact of the launch causes the background to be shaky. We stabilize the background by translation of each frame, the optimum translation being determined …

Use Of Advanced Synthesis Tools In Teaching Vlsi Design, Kevin Berwick, Dominic Nardone

Articles

No abstract provided.

Predictive Control For Dynamic Systems To Track Unknown Input In The Presence Of Time Delay, Yulan Li

Electronic Theses and Dissertations

This study investigated a tracking system to trace unknown signal in the presence oftime delay. A predictive control method is proposed in order to compensate the time delay. Root locus method is applied when designing the controller, parameter setting is carried out through error and trail technique in w-plane. State space equation is derived for the system, with special state chose of tracking error. To analyze the asymptotic stability of the proposed predictive control system, the Lyapunov function is constructed. It is shown that the designed system is asymptotically stable when input signal is rather low frequency signal. In order …

Analysis And Simulation Tools For Solar Array Power Systems, Nattorn Pongratananukul

Electronic Theses and Dissertations

This dissertation presents simulation tools developed specifically for the design of solar array power systems. Contributions are made in several aspects of the system design phases, including solar source modeling, system simulation, and controller verification. A tool to automate the study of solar array configurations using general purpose circuit simulators has been developed based on the modeling of individual solar cells. Hierarchical structure of solar cell elements, including semiconductor properties, allows simulation of electrical properties as well as the evaluation of the impact of environmental conditions. A second developed tool provides a co-simulation platform with the capability to verify the …

Solar-Based Single-Stage High-Efficiency Grid-Connected Inverter, Feng Tian

Electronic Theses and Dissertations

Renewable energy source plays an important role in the energy cogeneration and distribution. Traditional solar-based inverter system is two stages in cascaded, which has a simpler controller but low efficiency. A new solar-based single-stage grid-connected inverter system can achieve higher efficiency by reducing the power semiconductor switching loss and output stable and synchronized sinusoid current into the utility grid. Controlled by the digital signal processor, the inverter can also draw maximum power from the solar array, thereby maximizing the utilization of the solar array. In Chapter 1, a comparison between the traditional two-stage inverter and the single-stage inverter is made. …

Solution Of Electromagnetic Scattering Parameters And Radiation Patterns Of Arbitrary Body Of Revolution Radiators, Wendell Brokaw

Electronic Theses and Dissertations

A novel full wave analysis method to determine the scattering parameters and the radiation field intensities of arbitrary Body of Revolution (BOR) radiators consisting of impenetrable media is explored through derived components of modal analysis and the method of moments (MoM). Modal excitation is utilized to excite the structural feed; allowing for a more accurate measure of the scattering parameters of the total structure as opposed to the use of external excitation sources. The derivation of the mode matching method introduces a novel approach to achieving a frequency independent coupling matrix that will reduce the computational requirements for iterations utilized …

Optimization Of Network Parameters And Semi-Supervision In Gaussian Art Architectures, Roopa Chalasani

Electronic Theses and Dissertations

In this thesis we extensively experiment with two ART (adaptive resonance theory) architectures called Gaussian ARTMAP (GAM) and Distributed Gaussian ARTMAP (dGAM). Both of these classifiers have been successfully used in the past on a variety of applications. One of our contributions in this thesis is extensively experiments with the GAM and dGAM network parameters and appropriately identifying ranges for these parameters for which these architectures attain good performance (good classification performance and small network size). Furthermore, we have implemented novel modifications of these architectures, called semi-supervised GAM and dGAM architectures. Semi-supervision is a concept that has been used effectively …

Analysis And Design Of A Modular Solar-Fed Fault-Tolerant Power System With Maximum Power Point Tracking, Hussam Al-Atrash

Electronic Theses and Dissertations

Solar power is becoming ever more popular in a variety of applications. It is particularly attractive because of its abundance, renewability, and environment friendliness. Solar powered spacecraft systems have ever-expanding loads with stringent power regulation specifications. Moreover, they require a light and compact design of their power system. These constraints make the optimization of power harvest from solar arrays a critical task. Florida Power Electronics Center (FPEC) at UCF set to develop a modular fault-tolerant power system architecture for space applications. This architecture provides a number of very attractive features including Maximum Power Point Tracking (MPPT) and uniform power stress …

Detection Of The R-Wave In Ecg Signals, Sasanka Valluri

Electronic Theses and Dissertations

This thesis aims at providing a new approach for detecting R-waves in the ECG signal and generating the corresponding R-wave impulses with the delay between the original R-waves and the R-wave impulses being lesser than 100 ms. The algorithm was implemented in Matlab and tested with good results against 90 different ECG recordings from the MIT-BIH database. The Discrete Wavelet Transform (DWT) forms the heart of the algorithm providing a multi-resolution analysis of the ECG signal. The wavelet transform decomposes the ECG signal into frequency scales where the ECG characteristic waveforms are indicated by zero crossings. The adaptive threshold algorithms …

Design And Implementation Of Wireles Sensor Networks For Parking Management System, Sudhir Chandrasekar Kora

Electronic Theses and Dissertations

The technology of wirelessly networked micro sensors promises to revolutionize the way we interact with the physical environment. A new approach to solve parking-related issues of vehicles in parking lots using wireless sensor networks is presented. This approach enables the implementation of the Parking Management System (PMS®) in public parking lots found in Airports, Commercial Buildings, Universities, etc. The design architecture of the sensor nodes is discussed here. An overall view of the sensor network, which covers the whole of the parking lot, is also summarized. Detailed description of the software architecture that supports the hardware is provided. A sample …

Frequency Domain Independent Component Analysis Applied To Wireless Communications Over Frequency-Selective Channels, Yuan Liu

Electronic Theses and Dissertations

In wireless communications, frequency-selective fading is a major source of impairment for wireless communications. In this research, a novel Frequency-Domain Independent Component Analysis (ICA-F) approach is proposed to blindly separate and deconvolve signals traveling through frequency-selective, slow fading channels. Compared with existing time-domain approaches, the ICA-F is computationally efficient and possesses fast convergence properties. Simulation results confirm the effectiveness of the proposed ICA-F. Orthogonal Frequency Division Multiplexing (OFDM) systems are widely used in wireless communications nowadays. However, OFDM systems are very sensitive to Carrier Frequency Offset (CFO). Thus, an accurate CFO compensation technique is required in order to achieve acceptable …

Control And Topology Improvements In Half-Bridge Dc-Dc Converters, Songquan Deng

Electronic Theses and Dissertations

Efficiency and transient response are two key requirements for DC-DC converters. Topology and control are two key topics in this dissertation. A variety of techniques for DC-DC converter performance improvement are presented in this work. Focusing on the efficiency issue, a variety of clamping techniques including both active and passive methods are presented after the ringing issues in DC-DC converters are investigated. By presenting the clamping techniques, a big variety of energy management concepts are introduced. The active bridge-capacitor tank clamping and FET-diode-capacitor tank clamping are close ideas, which transfer the leakage inductor energy to clamping capacitor to prevent oscillation …

Debris Tracking In A Semistable Background, Karthikkalathi Vanumamalai

Electronic Theses and Dissertations

Object Tracking plays a very pivotal role in many computer vision applications such as video surveillance, human gesture recognition and object based video compressions such as MPEG-4. Automatic detection of any moving object and tracking its motion is always an important topic of computer vision and robotic fields. This thesis deals with the problem of detecting the presence of debris or any other unexpected objects in footage obtained during spacecraft launches, and this poses a challenge because of the non-stationary background. When the background is stationary, moving objects can be detected by frame differencing. Therefore there is a need for …

Investigation Of High-K Gate Dielectrics And Metals For Mosfet Devices., Sriram Mannargudi Seshadri

Electronic Theses and Dissertations

Progress in advanced microlithography and deposition techniques have made feasible high- k dielectric materials for MOS transistors. The continued scaling of CMOS devices is pushing the Si-SiO2 to its limit to consider high-k gate dielectrics. The demand for faster, low power, smaller, less expensive devices with good functionality and higher performance increases the demand for high-k dielectric based MOS devices. This thesis gives an in-depth study of threshold voltages of PMOS and NMOS transistors using various high-k dielectric materials like Tantalum pent oxide (Ta2O5), Hafnium oxide (HfO2), Zirconium oxide (ZrO2) and Aluminum oxide (Al2O3) gate oxides. Higher dielectric constant may …

Real-Time Multi-Spectral Image Processing On The Adsp-Bf533 Dsp, Stephen Niall Coffey

Theses

As the need to process multi-spectral images in real-time is becoming more prevalent, the pressure on Integrated Circuit (IC) manufacturers to produce cheap and reliable devices capable of handling the demands of such operations is growing. This project investigates the ADSP-BF533 Blackfin® Digital Signal Processor (DSP) and its ability to support a real-time multi-spectral imaging system. The Blackfin® DSP, incorporating the Analog Devices/Intel Micro Signal Architecture (MSA), are a broad family of 16-bit fixed-point product with a dual Multiply Accumulate (MAC) core.

Using the MicroC/OS-II Real-time Operating System (RTOS), which is a completely portable and scaleable pre-emptive real-time kernel, the …

Signal Flow Analysis, Partha P. Banerjee

Electrical and Computer Engineering Faculty Publications

Signal flow graphs are a viable alternative to block diagrammatic representation of a system. What makes signal flow graphs attractive is that certain features from graph theory can be applied to the simplification and the synthesis of complex systems.

Functional Nanoparticles In Thin Films As Sensing Media, Elena A. Guliants, Ryan Schwarb, Hope Bearbower, James R. Gord, Christopher E. Bunker

Electrical and Computer Engineering Faculty Publications

The combination of unique properties offered by materials on the nanoscale with the increased role of surface chemistry in nanostructured solids makes core-shell nanoparticles extremely attractive for application to "smart" thin-film coatings. Sensing properties of nanoparticle-based thin films were studied in several systems containing organic-coated semiconductor and metallic particles. In semiconductors, the interaction of organic shell and/or thin-film "matrix" with the environment results in changes in the nanoparticle's surface states, altering the optical properties of the thin film. Measuring the electrical properties of thin films composed of metallic cores with hydrocarbon shells offers another mechanism to monitor the local environment …

Multi-Channel Audio Time-Scale Modification, David Dorran, Robert Lawlor, Eugene Coyle

Conference papers

Phase vecoder based approaches to audio time-scale modification introduce a reverberant artefact into the time scaled output. Recent techniques have been developed to reduce the presence of this artefact; however, these techniques have the effect of introducing additional issues relating to their application to multi-channel recordings. This paper addresses these issues by collectively analysing all channels prior to time-scaling each individual channel.

A Novel Framework For Radio Resource Management In Ieee 802.11 Wireless Lans, Mark Davis, Tristan Raimondi

Conference papers

In this paper we address the need to characterize and quantify resource usage in IEEE 802.11 WLANs in order to support radio resource management. We present a compact and intuitive framework for performance characterization and resource utilization that is based upon the concept of MAC bandwidth components. These MAC bandwidth components are directly related to the transmission rate and serve to quantify the resource requirements associated with accessing the wireless medium. We also introduce a graphical technique for presenting these MAC bandwidth components that illustrates how WLAN stations interact in contending for access to the wireless medium. We demonstrate the …

Coverage Path Planning And Control For Autonomous Mobile Robots, Mohanakrishnan Balakrishnan

Electronic Theses and Dissertations

Coverage control has many applications such as security patrolling, land mine detectors, and automatic vacuum cleaners. This Thesis presents an analytical approach for generation of control inputs for a non-holonomic mobile robot in coverage control. Neural Network approach is used for complete coverage of a given area in the presence of stationary and dynamic obstacles. A complete coverage algorithm is used to determine the sequence of points. Once the sequences of points are determined a smooth trajectory characterized by fifth order polynomial having second order continuity is generated. And the slope of the curve at each point is calculated from …

Study Of Oxide Breakdown, Hot Carrier And Nbti Effects On Mos Device And Circuit Reliability, Yi Liu

Electronic Theses and Dissertations

As CMOS device sizes shrink, the channel electric field becomes higher and the hot carrier (HC) effect becomes more significant. When the oxide is scaled down to less than 3 nm, gate oxide breakdown (BD) often takes place. As a result, oxide trapping and interface generation cause long term performance drift and related reliability problems in devices and circuits. The RF front-end circuits include low noise amplifier (LNA), local oscillator (LO) and mixer. It is desirable for a LNA to achieve high gain with low noise figure, a LO to generate low noise signal with sufficient output power, wide tuning …

Giant Magneto-Impedance Effect In Thin Film Layered Structures, Amruta Borge

Electronic Theses and Dissertations

Recently, the giant magneto impedance (GMI) effect has been studied extensively because of its potential applications in sensor elements. The focus of this thesis work is to explore different compositions and processing conditions for CoSiB and NiFe thin films to obtain the soft magnetic properties and to evaluate their potential use in GMI sensor applications. Prior to this study, an MH Looper was constructed, which was extremely important and provided the basic magnetic characterization of the many ferromagnetic thin films deposited during this work. The CoSiB films were co-sputter deposited in an ultra high vacuum chamber. Films with different relative …

Effect Of Annealing On Copper Thin Films:The Classical Size Effect And Agglomeration, Parag Gadkari

Electronic Theses and Dissertations

With continued shrinking of CMOS technology to reduce the gate delay times, an increase in the resistivity of the metal corresponding to the wire dimension is a concern. This phenomenon of increase in resistivity with decreasing dimension of the thin metallic film or interconnect is known as the "classical size effect". Various theories have been postulated to explain the phenomenon of classical size effect; these theories can be broadly classified as resistivity due to scattering arising from surface and grain boundaries. The total resistivity of metals depends on the electron scattering due to impurities, phonons, surfaces, grain boundaries, and other …

Stabilization And Tracking Of The Van Der Pol Oscillator, Xin Zhao

Electronic Theses and Dissertations

In this thesis, the stabilization and tracking problem of the Van der Pol oscillator is studied by using advanced control techniques. First, the linear state feedback and linear adaptive state feedback controllers for the stabilization problem are designed. Then, non-linear state feedback and output feedback controllers are proposed for the tracking problem with known parameters. Finally, a dynamic output feedback controller based on adaptive backstepping technique is introduced for the tracking problem when all parameters of the Van der Pol system are unknown.

Speaker Identification Based On Discriminative Vector Quantization And Data Fusion, Guangyu Zhou

Electronic Theses and Dissertations

Speaker Identification (SI) approaches based on discriminative Vector Quantization (VQ) and data fusion techniques are presented in this dissertation. The SI approaches based on Discriminative VQ (DVQ) proposed in this dissertation are the DVQ for SI (DVQSI), the DVQSI with Unique speech feature vector space segmentation for each speaker pair (DVQSI-U), and the Adaptive DVQSI (ADVQSI) methods. The difference of the probability distributions of the speech feature vector sets from various speakers (or speaker groups) is called the interspeaker variation between speakers (or speaker groups). The interspeaker variation is the measure of template differences between speakers (or speaker groups). All …

Analysis And Design Of Miniaturized Rf Saw Duplexer Package, Hao Dong

Electronic Theses and Dissertations

This dissertation provides a comprehensive methodology for accurate analysis and design of miniaturized radio frequency (RF) surface acoustic wave (SAW) duplexer package. Full-wave analysis based on the three dimensional (3-D) finite element method (FEM) is successfully applied to model the package. The die model is obtained by combining the acoustics and die busbars parasitics models. The acoustics model is obtained using the coupling-of-models (COM) technique. The die busbars, bonding wires and printed circuit board (PCB) are modeled using full-wave analysis. After that, the models of package, die, and bonding wires are assembled together to get the total response. To take …

Preparation And Characterization Of Cigss Solar Cells And Pv Module Data Analysis, Jyoti Shirolikar

Electronic Theses and Dissertations

In this thesis, multiple activities have been carried out in order to improve the process of CIGSS solar cell fabrication on a 4" x 4" substrate. The process of CIGSS solar cell fabrication at FSEC's PV Materials Lab involves a series of steps that were all carried out manually in the past. A LABVIEW program has been written to carry out automated sputter deposition of Mo back contact, CuGa, In metallic precursors on a soda lime glass substrate using a stepper motor control for better uniformity. Further, selenization/ sulfurization of these precursors was carried out using rapid thermal processing (RTP). …

Interconnection, Interface And Instrumentation For Micromachined Chemical Sensors, Naveenkumar Srinivasaiah Palsandram

Electronic Theses and Dissertations

In realizing a portable chemical analysis system, adequate partitioning of a reusable component and a disposable is required. For successful implementation of micromachined sensors in an instrument, reliable methods for interconnection and interface are in great demand between these two major parts. This thesis work investigates interconnection methods of micromachined chip devices, a hybrid fluidic interface system, and measurement circuitry for completing instrumentation. The interconnection method based on micromachining and injection molding techniques was developed and an interconnecting microfluidic package was designed, fabricated and tested. Alternatively, a plug-in type design for a large amount of sample flow was designed and …

Studies Of Liquid Crystal Response Time, Haiying Wang

Electronic Theses and Dissertations

In this dissertation, the response time issue of the liquid crystal (LC) devices is investigated in meeting the challenges for display and photonic applications. The correlation between the LC director response time and the optical response time is derived theoretically and confirmed experimentally. A major contribution of this thesis is that, based on the small angle approximation, we derive rigorous analytical solutions for correlating the LC director response time to its consequent optical response times (both rise and decay) of a vertical-aligned nematic LC cell. This work successfully fills the gap in the literature of LCD switching dynamics. An important …