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Rain Rate Retrieval Algorithm For Aquarius/Sac-D Microwave Radiometer, Rosa Ana Menzerotolo 2011 University of Central Florida

Rain Rate Retrieval Algorithm For Aquarius/Sac-D Microwave Radiometer, Rosa Ana Menzerotolo

Electronic Theses and Dissertations

Microwave radiometers are used to measure blackbody microwave emissions emitted by natural targets. Radiative transfer theory provides a well founded physical relationship between the atmosphere and surface geophysical parameters and the brightness temperature measured by these radiometers. The atmospheric brightness temperature is proportional to the integral of the microwave absorption of water vapor, oxygen, and liquid water between the top of the atmosphere and the surface. Inverse radiative transfer models use to retrieve the water vapor, cloud liquid and oxygen content in the atmosphere are very well known; however, the retrieval of rain rate in the atmosphere is still a …


Modeling, Design And Fabrication Of Orthogonal And Psuedo-Orthogonal Frequency Coded Saw Wireless Spread Spectrum Rfid Sensor Tags, Nancy Saldanha 2011 University of Central Florida

Modeling, Design And Fabrication Of Orthogonal And Psuedo-Orthogonal Frequency Coded Saw Wireless Spread Spectrum Rfid Sensor Tags, Nancy Saldanha

Electronic Theses and Dissertations

Surface acoustic wave (SAW) sensors offer a wireless, passive sensor solution for use in numerous environments where wired sensing can be expensive and infeasible. Single carrier frequency SAW sensor embodiments such as delay lines, and resonators have been used in single sensor environments where sensor identification is not a necessity. The orthogonal frequency coded (OFC) SAW sensor tag embodiment developed at UCF uses a spread spectrum approach that allows interrogation in a multi-sensor environment and provides simultaneous sensing and sensor identi- fication. The SAW device is encoded via proper design of multiple Bragg reflectors at differing frequencies. To enable accurate …


Incremental Lifecycle Validation Of Knowledge-Based Systems Through Commonkads, Feras Batarseh 2011 University of Central Florida

Incremental Lifecycle Validation Of Knowledge-Based Systems Through Commonkads, Feras Batarseh

Electronic Theses and Dissertations

This dissertation introduces a novel validation method for knowledge-based systems (KBS). Validation is an essential phase in the development lifecycle of knowledge-based systems. Validation ensures that the system is valid, reliable and that it reflects the knowledge of the expert and meets the specifications. Although many validation methods have been introduced for knowledge-based systems, there is still a need for an incremental validation method based on a lifecycle model. Lifecycle models provide a general framework for the developer and a mapping technique from the system into the validation process. They support reusability, modularity and offer guidelines for knowledge engineers to …


Class F And Inverse Class F Power Amplifier Subject To Electrical Stress Effect, Giji Skaria 2011 University of Central Florida

Class F And Inverse Class F Power Amplifier Subject To Electrical Stress Effect, Giji Skaria

Electronic Theses and Dissertations

This study investigated the Class F and inverse Class F RF power amplifier operating at 5.8 GHz. The major challenging issue in design and implementation of CMOS power transistor is the breakdown voltage especially in sub-micron CMOS technologies. In order to eliminate this problem a Cascode topologies were implemented to reduce the Drain-toSource voltage (stress). A Cascode Class F & Inverse Class F RF power amplifier were designed, and optimized in order to improve efficiency and reliability using 0.18µm CMOS technology process. A 50% decrease in the stress has been achieved in the Cascode class-F and Inverse class F amplifiers. …


Study Of Esd Effects On Rf Power Amplifiers, Raju, Divya Narasimha 2011 University of Central Florida

Study Of Esd Effects On Rf Power Amplifiers, Raju, Divya Narasimha

Electronic Theses and Dissertations

Today, ESD is a major consideration in the design and manufacture of ICs. ESD problems are increasing in the electronics industry because of the increasing trend toward higher speed and smaller device sizes. There is growing interest in knowing the effects of ESD protection circuit on the performance of semiconductor integrated circuits (ICs) because of the impact it has on core RF circuit performance. This study investigated the impact of ESD protection circuit on RF Power amplifiers. Even though ESD protection for digital circuits has been known for a while, RF-ESD is a challenge. From a thorough literature search on …


Real-Time Beamforming Using High-Speed Fpgas At The Allen Telescope Array, William C. Barott, Oren Milgrome, Melvyn Wright, David MacMahon, Tom Kilsdonk, Peter Backus, Matt Dexter 2011 Embry-Riddle Aeronautical University

Real-Time Beamforming Using High-Speed Fpgas At The Allen Telescope Array, William C. Barott, Oren Milgrome, Melvyn Wright, David Macmahon, Tom Kilsdonk, Peter Backus, Matt Dexter

Department of Electrical Engineering and Computer Science - Daytona Beach

The Allen Telescope Array (ATA) at the Hat Creek Radio Observatory (HCRO) is a wide‐field panchromatic radio telescope currently consisting of 42 offset‐Gregorian antennas each with a 6 m aperture, with plans to expand the array to 350 antennas. Through unique back‐end hardware, the ATA performs real‐time wideband beamforming with independent subarray capabilities and customizable beam shaping. The beamformers enable science observations requiring the full gain of the array, time domain (nonintegrated) output, and interference excision or orthogonal beamsets. In this paper we report on the design of this beamformer, including architecture and experimental results. Furthermore, we address some practical …


Tsv Fault-Tolerant Mechanisms With Application To 3d Clock Networks, Chiao Ling Lung, Jui Hung Chien, Yiyu Shi, Shih Chieh Chang 2011 Missouri University of Science and Technology

Tsv Fault-Tolerant Mechanisms With Application To 3d Clock Networks, Chiao Ling Lung, Jui Hung Chien, Yiyu Shi, Shih Chieh Chang

Electrical and Computer Engineering Faculty Research & Creative Works

Three-dimensional integrated circuit (3D IC) has become an emerging technology in view of its advantages in packing density and flexibility in heterogeneous integration. through Silicon Via (TSV) formation is one of the keys enabling technologies for 3D ICs. While TSVs provide vertical connections between different dies for higher performance, they suffer from random open defects and thermo-mechanical stress. the potential yield loss can significantly increase the mass production cost, which in turn affects the profitability of 3D ICs. to address the TSV reliability issues, double TSV, shared spare TSV and TSV fault tolerant unit (TFU) techniques have been developed. in …


Soft Feedback Turbo Equalization For Underwater Acoustic Communications, Amirhossein Rafati, Huang Lou, Yahong Rosa Zheng, Chengshan Xiao 2011 Missouri University of Science and Technology

Soft Feedback Turbo Equalization For Underwater Acoustic Communications, Amirhossein Rafati, Huang Lou, Yahong Rosa Zheng, Chengshan Xiao

Electrical and Computer Engineering Faculty Research & Creative Works

In this paper, a low-complexity turbo detection scheme is proposed for single-carrier multiple-input multiple output (MIMO) underwater acoustic (UWA) communications that employs low-density parity-check (LDPC) channel coding. the proposed iterative soft feedback equalization (SFE) algorithm offers a novel approach to combating error propagation by utilizing the past soft decisions to mitigate inter-symbol interference. in addition, its computational complexity grows only linearly with the number of equalizer coefficients, compared to the quadratic complexity of minimum mean square error-Based linear turbo equalizer. Performance of the proposed detection scheme is verified through experimental data collected in MACE10. Experimental results show that it provides …


A Semantic Agent Framework For Cyber-Physical Systems, Jing Lin, Sahra Sedigh, Ann K. Miller 2011 Missouri University of Science and Technology

A Semantic Agent Framework For Cyber-Physical Systems, Jing Lin, Sahra Sedigh, Ann K. Miller

Electrical and Computer Engineering Faculty Research & Creative Works

The development of accurate models for cyber-physical systems (CPSs) is hampered by the complexity of these systems, fundamental differences in the operation of cyber and physical components, and significant interdependencies among these components. Agent-based modeling shows promise in overcoming these challenges, due to the flexibility of software agents as autonomous and intelligent decision-making components. Semantic agent systems are even more capable, as the structure they provide facilitates the extraction of meaningful content from the data provided to the software agents. In this book chapter, we present a multi-agent model for a CPS, where the semantic capabilities are underpinned by sensor …


A Unified Model-Based Fault Diagnosis Scheme For Nonlinear Discrete-Time Systems With Additive And Multiplicative Faults, Hasan Ferdowsi, Sarangapani Jagannathan 2011 Missouri University of Science and Technology

A Unified Model-Based Fault Diagnosis Scheme For Nonlinear Discrete-Time Systems With Additive And Multiplicative Faults, Hasan Ferdowsi, Sarangapani Jagannathan

Electrical and Computer Engineering Faculty Research & Creative Works

In this paper, a novel model-Based fault diagnosis scheme is proposed for a class of uncertain nonlinear discrete-time systems which can be subjected to both additive and multiplicative faults. Faults are detected by using a novel (FD) observer consisting of two online approximators in discrete-time (OLAD) and a robust adaptive term. Upon detection, a fault diagnosis scheme is introduced to determine the fault type by monitoring the input residual generated via the first OLAD output. Then the appropriate OLAD is included in the observer while the other OLAD is switched off. Next, by using both the parameter update law of …


Frequency Domain Turbo Equalization For No-Cp Single-Carrier Mimo Underwater Acoustic Communications, Longbao Wang, Jun Tao, Yahong Rosa Zheng 2011 Missouri University of Science and Technology

Frequency Domain Turbo Equalization For No-Cp Single-Carrier Mimo Underwater Acoustic Communications, Longbao Wang, Jun Tao, Yahong Rosa Zheng

Electrical and Computer Engineering Faculty Research & Creative Works

This paper proposes a frequency-domain turbo detection scheme for single-carrier, multiple-input, multiple output (MIMO) underwater acoustic (UWA) transmission without using cyclic prefix (CP), aiming to achieve a low detection complexity and a high transmission efficiency simultaneously. The received data stream is divided into consecutive blocks, and each block is equalized in the frequency domain. to enable the frequency-domain equalization, inter-block-interference (IBI) cancellation and CP reconstruction are necessary for each block. the IBI is removed by using the currently estimated channel and the detected symbols from the previous block. the CP reconstruction for the current iteration of the turbo equalization is …


Neural Network-Based Optimal Control For Trajectory Tracking Of A Helicopter Uav, David Nodland, H. Zargarzadeh, S. Jagannathan 2011 Missouri University of Science and Technology

Neural Network-Based Optimal Control For Trajectory Tracking Of A Helicopter Uav, David Nodland, H. Zargarzadeh, S. Jagannathan

Electrical and Computer Engineering Faculty Research & Creative Works

Helicopter unmanned aerial vehicles (UAVs) may be widely used for both military and civilian operations. Because these helicopters are underactuated nonlinear mechanical systems, high-performance controller design for them presents a challenge. This paper presents an optimal controller design for trajectory tracking of a helicopter UAV using a neural network (NN). the state-feedback control system utilizes the backstepping methodology, employing kinematic and dynamic controllers. the online approximator-Based dynamic controller learns the infinite-horizon Hamilton-Jacobi-Bellman (HJB) equation in continuous time and calculates the corresponding optimal control input to minimize the HJB equation forward-in-time. Optimal tracking is accomplished with a single NN utilized for …


Thermal-Aware Cell And Through-Silicon-Via Co-Placement For 3d Ics, Jason Cong, Guojie Luo, Yiyu Shi 2011 Missouri University of Science and Technology

Thermal-Aware Cell And Through-Silicon-Via Co-Placement For 3d Ics, Jason Cong, Guojie Luo, Yiyu Shi

Electrical and Computer Engineering Faculty Research & Creative Works

Existing thermal-aware 3D placement methods assume that the temperature of 3D ICs can be optimized by properly distributing the power dissipations and ignoring the heat conductivity of though-silicon-vias (TSVs). However, our study indicates that this is not exactly correct. While considering the thermal effect of TSVs during placement appears to be quite complicated, we are able to prove that when the TSV area in each bin is proportional to the lumped power consumption in that bin, together with the bins in all the tiers directly above it, the peak temperature is minimized. based on this criterion, we implement a thermal-aware …


Design And Ground Plane Optimization Of A Cpw-Fed Ultra-Wideband Antenna, MOHAMMED AL-HUSSEINI, ALI RAMADAN, YOUSSEF TAWK, ALI EL-HAJJ, KARIM Y. KABALAN 2011 TÜBİTAK

Design And Ground Plane Optimization Of A Cpw-Fed Ultra-Wideband Antenna, Mohammed Al-Husseini, Ali Ramadan, Youssef Tawk, Ali El-Hajj, Karim Y. Kabalan

Turkish Journal of Electrical Engineering and Computer Sciences

In this paper, an ultra-wideband antenna based on an egg-shaped conductor and a co-planar waveguide (CPW) feed is presented. The ground plane incorporates an egg-shaped slot with parametrized center and dimensions. By resizing the slot and moving its center, a slotted or a partial ground can be obtained. Based on this configuration, a parametric study that aims at achieving the best ultra-wideband (UWB) response of the antenna is done. The study shows that an excellent UWB response is achieved for a certain ground slot size, beyond which the response starts to degrade. However, as the slot size tends to infinity, …


Application Of A Hybrid Evolutionary Technique For Efficiency Determination Of A Submersible Induction Motor, MÜMTAZ MUTLUER, OSMAN BİLGİN 2011 TÜBİTAK

Application Of A Hybrid Evolutionary Technique For Efficiency Determination Of A Submersible Induction Motor, Mümtaz Mutluer, Osman Bi̇lgi̇n

Turkish Journal of Electrical Engineering and Computer Sciences

Electric motors are the largest consumers of electricity in plants and induction motors constitute nearly two-thirds of them. The replacement of in-service induction motors with more efficient ones is a very important strategy for energy savings and consequently nearly 30 different methods have been used to determine the efficiency of induction motors in the last 2 decades. This paper aims to develop the efficiency determination of a 20 Hp submersible induction motor. Due to getting perfect efficiency of the submersible induction motor, a robust hybrid evolutionary optimization technique, which consists of a genetic algorithm and simulated annealing, is used. The …


An Algorithm To Minimize Within-Class Scatter And To Reduce Common Matrix Dimension For Image Recognition, ÜMİT ÇİĞDEM TURHAL, ALPASLAN DUYSAK 2011 TÜBİTAK

An Algorithm To Minimize Within-Class Scatter And To Reduce Common Matrix Dimension For Image Recognition, Ümi̇t Çi̇ğdem Turhal, Alpaslan Duysak

Turkish Journal of Electrical Engineering and Computer Sciences

In this paper, a new algorithm using 2DPCA and Gram-Schmidt Orthogonalization Procedure for recognition of face images is proposed. The algorithm consists of two parts. In the first part, a common feature matrix is obtained; and in the second part, the dimension of the common feature matrix is reduced. Resulting common feature matrix with reduced dimension is used for face recognition. Column and row covariance matrices are obtained by applying 2DPCA on the column and row vectors of images, respectively. The algorithm then applies eigenvalue-eigenvector decomposition to each of these two covariance matrices. Total scatter maximization is achieved taking the …


Design And Development Of Workstation For Microparts Manipulation And Assembly, EMRAH DENİZ KUNT, AHMET TEOMAN NASKALİ, İSLAM SHOUKRY MOHAMMED KHALIL, ASIF SABANOVIC, EBUBEKİR YÜKSEL 2011 TÜBİTAK

Design And Development Of Workstation For Microparts Manipulation And Assembly, Emrah Deni̇z Kunt, Ahmet Teoman Naskali̇, İslam Shoukry Mohammed Khalil, Asif Sabanovic, Ebubeki̇r Yüksel

Turkish Journal of Electrical Engineering and Computer Sciences

In this paper, microassembly system design issues are discussed with requirements, constraints and necessities for the development of an assembly platform, and these issues are shown over a versatile and reconfigurable microassembly workstation which is designed and realized as a research tool for investigation of the problems in microassembly and micromanipulation tasks. First prototype of a workstation and the development of a second prototype with enhancements on mechanical and control structure of the system are presented with details on the configuration of the systems. In addition, several experiments using a workstation are presented both on the first and the second …


Cross-Layer Design For Mobile Ad-Hoc Unmanned Aerial Vehicle Communication Networks, Abdel Ilah Nour Alshbatat 2011 Western Michigan University

Cross-Layer Design For Mobile Ad-Hoc Unmanned Aerial Vehicle Communication Networks, Abdel Ilah Nour Alshbatat

Dissertations

Mobile Ad-Hoc network (MANET) is a popular type of wireless network that is formed by a collection of mobile nodes. Each node in such a network has the capability to communicate with its neighbors and non-neighbors through a wireless medium without using any existing network infrastructure. Due to the lack of infrastructure, all nodes in Ad-Hoc network are designed to act as an end system and a router for other nodes.

Traditionally, the dominant design methodology for network protocols was based on the open systems interconnection (OSI) reference model. This methodology divided the stack into seven layers in which each …


Spectrum Adaptation In Cognitive Radio Systems With Operating Constraints, Deepak R. Joshi 2011 Old Dominion University

Spectrum Adaptation In Cognitive Radio Systems With Operating Constraints, Deepak R. Joshi

Electrical & Computer Engineering Theses & Dissertations

The explosion of high-data-rate-demanding wireless applications such as smart-phones and wireless Internet access devices, together with growth of existing wireless services, are creating a shortage of the scarce Radio Frequency (RF) spectrum. However, several spectrum measurement campaigns revealed that current spectrum usage across time and frequency is inefficient, creating the artificial shortage of the spectrum because of the traditional exclusive "command-and-control" model of using the spectrum. Therefore, a new concept of Cognitive Radio (CR) has been emerging recently in which unlicensed users temporarily borrow spectrum from the licensed Primary Users (PU) based on the Dynamic Spectrum Access (DSA) technique that …


Measurement And Characterization Of Terahertz Radiation Propagating Through A Parallel Plate Waveguide, Matthew George Wachsmuth 2011 Portland State University

Measurement And Characterization Of Terahertz Radiation Propagating Through A Parallel Plate Waveguide, Matthew George Wachsmuth

Dissertations and Theses

As the amount of study into the terahertz (THz) region of the electromagnetic spectrum steadily increases, the parallel plate waveguide has emerged as a simple and effective fixture to perform many experiments. The ability to concentrate THz radiation into a small area or volume enables us to analyze smaller samples and perform more repeatable measurements, which is essential for future research. While the fundamental physics of PPW transmission are understood mathematically, the practical knowledge of building such a fixture for the THz domain and taking measurements on it with a real system needs to be built up through experience. In …


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